RESUMO
Oxidative stress and inflammation act on skin squamous cell carcinoma (SSCC) development and progression. Curative therapy for SSCC patients is mainly based on surgical resection, which can cause various sequelae. Silver ions have in vitro activities over tumor cells, while nimesulide has antioxidant and anti-inflammatory activities. This study aimed to evaluate the effects of a silver(I) complex with nimesulide (AgNMS) incorporated in a sustained release device based on bacterial cellulose membrane, named AgNMS@BCM, on topic SSCC treatment. The antiproliferative effect of AgNMS complex was evaluated in the SCC4, SCC15 and FaDu SCC lines. AgNMS complex activity on exposure of phosphatidylserine (PS) residues and multicaspase activation were evaluated on FaDu cells by flow cytometry. The AgNMS@BCM effects were evaluated in a SSCC model induced by 7,12-dimethylbenzanthracene/12-o-tetradecanoyl-phorbol-13-acetate (DMBA/TPA) in mice. Toxicity and tumor size were evaluated throughout the study. AgNMS complex showed antiproliferative activity in SCC15 and FaDu lines in low to moderate concentrations (67.3 µM and 107.3 µM, respectively), and induced multicaspase activation on FaDu cells. The AgNMS@BCM did not induce toxicity and reduced tumor size up to 100%. Thus, the application of AgNMS@BCM was effective and safe in SSCC treatment in mice, and can be seen as a potential and safe agent for topic treatment of SSCC in humans.
RESUMO
Myrcia bella is a medicinal plant used for the treatment of diabetes, hemorrhages, and hypertension in Brazilian folk medicine. Considering that plant extracts are attractive sources of new drugs, the aim of the present study was to verify the influence of incorporating 70% hydroalcoholic of M. bella leaves in nanostructured lipid systems on the mutagenic and antifungal activities of the extract. In this work, we evaluated the antifungal potential of M. bella loaded on the microemulsion against Candida sp for minimum inhibitory concentration, using the microdilution technique. The system was composed of polyoxyethylene 20 cetyl ether and soybean phosphatidylcholine (10%), grape seed oil, cholesterol (10%: proportion 5/1), and purified water (80%). To investigate the mutagenic activity, the Ames test was used with the Salmonella Typhimurium tester strains. M. bella, either incorporated or free, showed an important antifungal effect against all tested strains. Moreover, the incorporation surprisingly inhibited the mutagenicity presented by the extract. The present study attests the antimicrobial properties of M. bella extract, contributing to the search for new natural products with biological activities and suggesting caution in its use for medicinal purposes. In addition, the results emphasize the importance of the use of nanotechnology associated with natural products as a strategy for the control of infections caused mainly by the genus Candida sp.
Assuntos
Myrtaceae , Plantas Medicinais , Antifúngicos/farmacologia , Mutagênicos , Extratos Vegetais/farmacologiaRESUMO
Bacterial cellulose (BC) produced by some bacteria, among them Gluconacetobacter xylinum, which secrets an abundant 3D networks fibrils, represents an interesting emerging biocompatible nanomaterial. Since its discovery BC has shown tremendous potential in a wide range of biomedical applications, such as artificial skin, artificial blood vessels and microvessels, wound dressing, among others. BC can be easily manipulated to improve its properties and/or functionalities resulting in several BC based nanocomposites. As example BC/collagen, BC/gelatin, BC/Fibroin, BC/Chitosan, etc. Thus, the aim of this review is to discuss about the applicability in biomedicine by demonstrating a variety of forms of this biopolymer highlighting in detail some qualities of bacterial cellulose. Therefore, various biomedical applications ranging from implants and scaffolds, carriers for drug delivery, wound-dressing materials, etc. that were reported until date will be presented.
Assuntos
Bactérias/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Celulose/química , Celulose/uso terapêutico , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/uso terapêutico , Animais , Anti-Infecciosos/química , Anti-Infecciosos/uso terapêutico , Bandagens , Celulose/análogos & derivados , Sistemas de Liberação de Medicamentos/métodos , Gluconacetobacter xylinus/química , Humanos , Polissacarídeos Bacterianos/análogos & derivados , Próteses e Implantes , Engenharia Tecidual/métodos , Alicerces Teciduais/químicaRESUMO
As alterações que caracterizam a senescência são facilmente observáveis ou mesmo sentidas por todos nós, mas os mecanismos biológicos que concorrem para o seu desenvolvimento permanecem, em grande parte, desconhecidos. Várias são as teorias que tentam explicar o mecanismo da gênese do envelhecimento celular, mas nenhuma delas conseguiu sucesso total, o que reflete a dificuldade de entender na íntegra este processo
Assuntos
Humanos , Masculino , Feminino , Idoso , Envelhecimento , Fatores Biológicos/genéticaRESUMO
Procurando verificar a participaçäo de rotavirus e adenovirus na etiologia da gastrenterite infantil, 280 amostras de fezes de crianças da faixa etária de 0 a 5 anos foram coletadas em Araraquara-SP, sendo 140 de crianças com diarréia e 140 do grupo de controle. A pesquisa desses vírus foi realizada através de um ensaio imunoenzimático (EIARA) e adicionalmente, rotavirus foi pesquisado através da eletroforese em gel de poliacrilamida (PAGE). No grupo diarréico, rotavirus foi detectado em 8,6% das amostras usando EIARA e em 7,9% usando PAGE. Nenhuma das amostras do grupo controle se mostrou positiva para esse vírus. Adenovirus foi detectado em 2,9% das amostras do grupo diarréico e em 1,4 % das fezes do grupo controle. Os resultados mostram que o rotavirus participam ativamente da etiologia da diarreia infantil em nossa cidade