RESUMEN
Prevention of infections is a very important issue in treating the burn wounds. The nanosilver dressings have many promising advantages, but absorption of silver ions and its adverse effects to the body were always a question. The aim of this study was to compare Silver serum levels and acute toxic effects of nanosilver on histopathology of organs (lungs, liver, kidney, spleen, and brain) in two types of AgiCoat and Acticoat (nanosilver) dressings on second-degree deep burn in rat. This is an experimental study conducted in our animal laboratory. We divided 24 Sprague-Dawley male rats weighing 300 to 350 randomly into two groups. After anesthesia, a second deep-degree burn was made over dorsal skins of rats by standard method. For group A, Agicoat and, for group B, Acticoat dressings were used. The dressings were changed every 3 days with AgiCoat and Acticoat, respectively. After 14 days, we got blood samples and tissue samples taken from heart, liver, kidneys, spleen, lungs, and brain and a sample from dorsal skin of the rat for histopathological examinations. The results showed that the levels of serum silver in both groups were significantly higher than the standard level (1.22 part per million (PM); AgiCoat, P = .017; Acticoat, P = .000), but there was no significant difference between the groups (P = .551). Examination of the relationship between the level of serum silver and histopathological changes in liver showed that hepatotoxicity of AgiCoat was higher compared with Acticoat and the difference was significant (P = .002). There were no pathological changes in brain, kidneys, spleen, heart, and lungs. Wound healing was faster in Acticoat group. The nanosilver dressings can cause toxicity in liver but not in kidney, brain, spleen, heart, and lungs. Liver pathology and hepatotoxicity were more prominent in AgiCoat group. Wound healing was faster in Acticoat group.
Asunto(s)
Vendajes , Encéfalo/patología , Quemaduras/terapia , Riñón/patología , Hígado/patología , Pulmón/patología , Poliésteres , Polietilenos , Animales , Antiinfecciosos Locales , Quemaduras/metabolismo , Quemaduras/patología , Modelos Animales de Enfermedad , Masculino , Nanopartículas del Metal , Ratas , Ratas Sprague-Dawley , Compuestos de Plata , Cicatrización de HeridasRESUMEN
Breast tumours consist of phenotypically diverse populations of breast cancer cells of which only a minority has the ability to form new tumours. The capacity for breast tumour development has been shown to be restricted to breast cancer stem cells with the CD44+/CD24(-/low) phenotype. These cells can resist apoptosis through mechanisms such as the regulation of Bcl-2. Identification of this population of cells is important because of its implication in the development of new therapeutic strategies. One hundred and forty-six primary operable breast cancer patients were investigated in order to identify the population of CD44+ and Bcl-2+ cells in paraffin-embedded tissues by immunohistochemistry. The prevalence of these phenotypes was then correlated with clinicopathological features. CD44 and Bcl-2 expression was detected in 86% and 82% of breast tumours, respectively. There was no significant correlation between CD44+ tumour cell prevalence and tumour characteristics, whereas the prevalence of CD44+ cells was associated with higher levels of Bcl-2 expression (P = 0.004). In univariate analysis, Bcl-2 expression was correlated with breast tumours of lower grade (P < 0.001) and fewer lymphatic metastases (P < 0.05). Our findings suggest that the prevalence of CD44+ tumour cells as a subpopulation of breast cancer stem cells was of no clinicopathological significance, but was correlated with higher Bcl-2 expression. This population of tumour cells may thus be more resistant to apoptosis. Targeting these cells in combination with current treatments may be more effective in treating breast cancer patients.