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1.
Asian J Pharm Sci ; 12(4): 386-393, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32104350

RESUMO

The aim of this study was to enhance the solubility and stability of Acacia concinna extract by loading in a microemulsion for topical application. Both physical appearance and biological activities of the extract-loaded microemulsion were determined in comparison with the extract solution. Pseudoternary phase diagrams of three oil types including tea seed oil, grape seed oil, and sesame oil, together with polysorbate 85 or the mixture of polysorbate 85 and sorbitan oleate as surfactants, and absolute ethanol as a co-surfactant were constructed to optimize the microemulsion area. The selected microemulsion was then characterized for droplet size, polydispersity index, and viscosity. Tea seed oil exhibited the highest microemulsion area in the phase diagram because it had the highest unsaturated fatty acid content. The microemulsion composed of tea seed oil (5%), polysorbate 85 (40%), ethanol (20%), and water (35%) exhibited Newtonian flow behavior with the droplet size and polydispersity index of 68.03 ± 1.09 nm and 0.44 ± 0.04, respectively. After 4% w/w of the extract was incorporated into the microemulsion, larger droplets size was observed (239.77 ± 12.69 nm) with a lower polydispersity index (0.37 ± 0.02). After storage in various conditions, both physical appearances and the stability of biological activity of the extract-loaded microemulsion were improved compared to the solution. Therefore, the A. concinna loaded microemulsion may be a promising carrier for further development into a topical formulation and clinical trials for pharmaceutical and cosmeceutical applications are also suggested.

2.
Cancer Med ; 5(7): 1566-79, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27061029

RESUMO

Stromal fibroblasts are an integral part of the tumor stroma and constantly interact with cancer cells to promote their initiation and progression. However, the role and function of dermal fibroblasts during the early stage of melanoma development remain poorly understood. We, therefore, designed a novel genetic approach to deactivate stromal fibroblasts at the onset of melanoma formation by targeted ablation of ß-catenin. To our surprise, melanoma tumors formed from ß-catenin-deficient group (B16F10 mixed with ß-catenin-deficient fibroblasts) appeared earlier than tumors formed from control group (B16F10 mixed with normal dermal fibroblasts). At the end point when tumors were collected, mutant tumors were bigger and heavier than control tumors. Further analysis showed that there were fewer amounts of stromal fibroblasts and myofibroblasts inside mutant tumor stroma. Melanoma tumors from control group showed reduced proliferation, down-regulated expression of cyclin D1 and increased expression of cyclin-dependent kinase inhibitor p16, suggesting dermal fibroblasts blocked the onset of melanoma tumor formation by inducing a cell cycle arrest in B16F10 melanoma cells. Furthermore, we discovered that dermal fibroblasts prevented epithelial-mesenchymal transition in melanoma cells. Overall, our findings demonstrated that dermal fibroblasts crosstalk with melanoma cells to regulate in vivo tumor development via multiple mechanisms, and the outcomes of their reciprocal interactions depend on activation states of stromal fibroblasts and stages of melanoma development.


Assuntos
Pontos de Checagem do Ciclo Celular , Transformação Celular Neoplásica/metabolismo , Transição Epitelial-Mesenquimal , Fibroblastos/metabolismo , Melanoma/metabolismo , Melanoma/patologia , Animais , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal/genética , Proteínas da Matriz Extracelular/metabolismo , Xenoenxertos , Humanos , Melanoma/etiologia , Melanoma Experimental , Camundongos , Camundongos Transgênicos , Estadiamento de Neoplasias , Transporte Proteico , Transdução de Sinais , Microambiente Tumoral , beta Catenina/genética , beta Catenina/metabolismo
3.
Int J Dermatol ; 55(10): e522-32, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27062495

RESUMO

BACKGROUND: Infantile hemangiomas (IH) are initially warm due to increased proliferation and perfusion then involute with apoptosis and reduced perfusion. Objective quantitative evaluation of IH treatment response is essential for improving outcomes. We applied a functional imaging method, dynamic infrared (IR) thermography, to investigate IH status versus control skin and over time. MATERIALS AND METHODS: A preliminary prospective observational study was conducted among 25 subjects with superficial or mixed IHs (< 19 months) over 59 clinic visits. Infrared images of IHs and control sites, standardized color images, and three-dimensional images were obtained. Tissue responses following application and removal of a cold stress were recorded with video IR thermography. Outcomes included areas under the curve during cooling (AUCcool ) and rewarming (AUCrw ) and thermal intensity distribution maps. RESULTS: AUCcool and AUCrw were significantly higher and cooling rate slower for IHs versus uninvolved tissue indicating greater heat, presumably due to greater perfusion and metabolism for the IH. IR distribution maps showed specific areas of high and low temperature. Significant changes in IH thermal activity were reflected in the difference (AUCcool - AUCrw ), with 6.2 at 2.2 months increasing to 37.6 at 12.8 months. IH cooling rate increased with age, indicating slower recovery, and interpreted as reduced proliferation and/or involution. CONCLUSIONS: Dynamic IR thermography was a well-tolerated, quantitative functional imaging modality appropriate for the clinic, particularly when structural changes, i.e., height, volume, color, were not readily observed. It may assist in monitoring progress, individualizing treatment, and evaluating therapies. CLINICAL TRIAL REGISTRATION: www.clinicaltrials.gov (Identifier NCT02061735).


Assuntos
Hemangioma Capilar/diagnóstico por imagem , Síndromes Neoplásicas Hereditárias/diagnóstico por imagem , Temperatura Cutânea , Pele/diagnóstico por imagem , Termografia/métodos , Área Sob a Curva , Temperatura Baixa , Feminino , Hemangioma Capilar/fisiopatologia , Humanos , Imageamento Tridimensional , Lactente , Raios Infravermelhos , Masculino , Síndromes Neoplásicas Hereditárias/fisiopatologia , Estudos Prospectivos , Gravação em Vídeo
4.
Int J Cosmet Sci ; 34(5): 402-15, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22691060

RESUMO

Reduction and prevention of health care-associated infections is a worldwide priority with emphasis on increasing hand hygiene compliance. Repetitive exposure to hand hygiene products and procedures is a significant factor in the development of occupational irritant hand dermatitis. Compliance has been difficult to achieve often due to skin irritation. The introduction of alcohol hand rubs has positively influenced compliance but rates remain lower than required. Genetic and environmental factors to the frequency and severity of irritant contact dermatitis have been identified. Because of the skin's role in innate immunity, maintenance of epidermal integrity is a key strategy for reducing health care-associated infections. In this review, we examine the interdependence of the two issues and the challenges of simultaneously accomplishing both goals. We emphasize research conducted among healthcare workers in their clinical settings. The factors that influence skin integrity and the challenges in meeting both goals simultaneously are explored. Cosmetic scientists have played key roles in the development of improved skin care products, and the issues present an excellent opportunity for them to provide potentially life-saving contributions to health care.


Assuntos
Infecção Hospitalar/prevenção & controle , Dermatite Irritante/etiologia , Desinfecção das Mãos/métodos , Controle de Infecções/métodos , Pessoal de Saúde , Humanos
5.
Dermatol Surg ; 38(9): 1490-6, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22672578

RESUMO

BACKGROUND: The pulsed-dye laser (PDL) is a potential adjunctive therapy for treatment of hyperemic and hypertrophic scars. OBJECTIVE: To compare the effects of early PDL treatment plus compression therapy (CT) with those of CT alone in patients undergoing burn scar reconstruction with split-thickness grafts on an extremity. METHODS: Laser treatments were applied to one half of the graft seam. Standard CT was applied to both halves. Laser treatment was repeated at 6-week intervals until one half reached sufficient clinical improvements. Each half was evaluated just before treatments using quantitative measures of color, scar height, biomechanical properties and clinical features using the Vancouver Scar Scale (VSS). RESULTS: Less quantitative scar erythema and height and greater tissue elasticity were observed after two or three treatments for PDL plus compression than with compression alone. VSS scores showed greater improvement for vascularity, pliability, pigmentation, and height for PDL plus compression than for compression alone. CONCLUSION: PDL treatment in combination with CT appears to reduce scar hyperemia and height and normalize the biomechanical properties of burn-related scars.


Assuntos
Cicatriz/patologia , Cicatriz/terapia , Bandagens Compressivas , Lasers de Corante/uso terapêutico , Adolescente , Adulto , Queimaduras/complicações , Criança , Cicatriz/fisiopatologia , Terapia Combinada , Elasticidade , Eritema/terapia , Feminino , Humanos , Masculino , Maleabilidade , Índice de Gravidade de Doença , Método Simples-Cego , Pele/patologia , Pele/fisiopatologia , Transplante de Pele , Adulto Jovem
6.
Arch Dermatol Res ; 303(2): 117-24, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21161543

RESUMO

Patients with a prosthetic limb report negative skin effects, including irritation, rash and chafing, which can lead to infection, discomfort and reduced wear time to significantly impact normal activities. The aims were to examine the epidermal integrity (transepidermal water loss, TEWL), stratum corneum (SC) hydration [moisture accumulation rate (MAT)], friction and biomechanical properties in active below the knee amputees and to determine the effects of an inert sock liner on skin condition. The liner reduced hydration, TEWL and friction and increased elasticity versus the amputee's conventional skin care methods. Residual limb TEWL was increased and MAT was reduced versus the contralateral normal skin. In a second study, we hypothesized that complete occlusion would decrease free amino acids (FAA) and quantified them by high performance liquid chromatography in an adult volar forearm model. Occlusion with a water vapor impermeable wet dressing led to increased TEWL, erythema and dryness and reduced MAT versus normal skin, comparable to the results in the amputees. The FAA levels were significantly reduced for the occluded sites. The results suggest that residual limb occlusion in amputees may block the formation of FAA in the upper SC. Therapies based on replacement of water binding FAAs, may alleviate the consequences of long-term occlusion.


Assuntos
Aminoácidos/análise , Membros Artificiais/efeitos adversos , Vestuário , Epiderme/química , Hipodermóclise , Perda Insensível de Água , Amputados , Fenômenos Biomecânicos , Água Corporal , Cromatografia Líquida de Alta Pressão , Dermatite/etiologia , Eczema/etiologia , Exantema/etiologia , Feminino , Fricção , Humanos , Perna (Membro) , Masculino , Higiene da Pele , Água
7.
Skin Res Technol ; 12(1): 43-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16420538

RESUMO

BACKGROUND/PURPOSE: Quantitative measurement of skin biomechanical properties has been used effectively in the investigation of physiological changes in tissue structure and function and to determine treatment efficacy. As the methods are applied to new questions, tissue characteristics that may influence the resultant biomechanical properties are important considerations in the research design. For certain applications, variables such as dermal thickness and subdermal tissue composition, as well as age and/or solar exposure, may influence the skin biomechanics. METHODS: We determined the influence of dermal thickness, tissue composition, and age on the skin biomechanical properties at the shoulder, thigh, and calf among 30 healthy females. We compared two devices, the Biomechanical Tissue Characterization System and the Cutometer SEM 575 Skin Elasticity Meter , to determine the effect of tissue sampling size. Dermal thickness was measured with 20 MHz ultrasound (Dermascan C) and tissue composition was inferred from anthropomorphic data. RESULTS: Skin thickness was significantly correlated with stiffness, energy absorption, and U(r)/U(f) for the shoulder. Body mass index (BMI) was significantly correlated with stiffness (negative correlation), energy absorption (positive), and skin thickness (negative) for the shoulder. Significant differences across body sites were observed. The calf was significantly different from the thigh and shoulders for all parameters (P<0.05, one-way anova). The calf had significantly lower laxity, laxity%, elastic deformation, energy absorption, elasticity, elasticity %, U(r), U(f), and U(r)/U(f) and significantly higher stiffness compared with the thighs and shoulders. sites. The thigh and shoulder sites were significantly different for all parameters except U(r)/U(f), elasticity %, laxity%, and stiffness. The dominant and non-dominant sides were significantly different. The dominant side (right for 90% of the subjects) had increased stiffness and decreased energy absorption (tissue softness, compliance) compared with the left side. A significant (P< or =0.02) negative relationship with age was seen for all biomechanical measures except stiffness at the shoulder. For the thigh and calf sites, significant negative correlations with age were found for elasticity %, U(r), and U(r)/U(f). Age and skin thickness were not correlated in this population. Skin thickness and age influenced the energy absorption at the shoulder site. The biological elasticity at the calf site could be predicted by age and BMI. The biological activity at the thigh site could be predicted by skin thickness and BMI. CONCLUSIONS: Significant regional variations in biomechanical properties and dominant side effects were observed. The biomechanical properties were significantly influenced by age. Certain properties varied with dermal thickness and tissue composition. The parameters were well correlated between the two instruments. The Cutometer, with its smaller aperture, was found to be more sensitive to age relationships.


Assuntos
Envelhecimento/fisiologia , Fenômenos Biomecânicos/instrumentação , Perna (Membro)/anatomia & histologia , Perna (Membro)/fisiologia , Estimulação Física/instrumentação , Fenômenos Fisiológicos da Pele , Pele/anatomia & histologia , Adulto , Idoso , Fenômenos Biomecânicos/métodos , Índice de Massa Corporal , Elasticidade , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Pessoa de Meia-Idade , Estimulação Física/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como Assunto
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