RESUMO
At present, liver transplantation remains the most effective treatment for acute liver failure and advanced cirrhosis, but its use and promotion are limited by insufficient organ donors, financial consideration, and requirements for lifelong immunosuppression. In recent years, stem cell transplantation has been recommended as an effective substitutive therapy for liver disease. Mesenchymal stem cells, also known as pluripotent interstitial stromal cells, are self-renewing cells that can be found in almost all postnatal organs and tissues, including the liver. Their potential to differentiate into hepatocytes and immunomodulatory properties provide new insights into the use of mesenchymal stem cells in the treatment of acute and chronic liver diseases. This article reviews the characteristics of mesenchymal stem cells, their mechanisms in the treatment of acute and chronic liver diseases, and related risks.
Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Exossomos , Fibrose/terapia , Falência Hepática Aguda/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Adolescente , Hepatócitos , Humanos , Regeneração Hepática/fisiologia , Pessoa de Meia-IdadeRESUMO
Image blur in acousto-optic tunable filters (AOTF's) has been a persistent problem. Here we describe the connection between transducer structure and image blur and experimentally measure it by using a 5-cm 12°-cut TeO(2) crystal of our design. With these quantitative results, we develop an image-processing method that minimizes AOTF-related image degradation. The combination of long crystal design and image processing results in substantially improved image contrast and spatial resolution relative to conventional AOTF imaging devices. We present high-magnification images of fluorescent actin fibers in cells in which we obtain a resolution of approximately 0.35 µm, representing the first successful use of an AOTF for ultra-high-resolution microscopy. Further improvements are also predicted.
