The repair and regeneration of articular cartilage represent important challenges for orthopedic investigators and surgeons worldwide due to its avascular, aneural structure, cellular arrangement, and dense extracellular structure. Although abundant efforts have been paid to provide tissue-engineered grafts, the use of therapeutically cell-based options for repairing cartilage remains unsolved in the clinic. Merging a clinical perspective with recent progress in nanotechnology can be helpful for developing efficient cartilage replacements. Nanomaterials, < 100 nm structural elements, can control different properties of materials by collecting them at nanometric sizes. The integration of nanomaterials holds promise in developing scaffolds that better simulate the extracellular matrix (ECM) environment of cartilage to enhance the interaction of scaffold with the cells and improve the functionality of the engineered-tissue construct. This technology not only can be used for the healing of focal defects but can also be used for extensive osteoarthritic degenerative alterations in the joint. In this review paper, we will emphasize the recent investigations of articular cartilage repair/regeneration via biomaterials. Also, the application of novel technologies and materials is discussed.
A growing interest in apoptosis, programmed cell death, in the last years is observed and leads to better understanding of molecular mechanisms during cell-cell signaling, cell-environment interaction and screening of drugs. This in turn results in emerging of new assays and development of more accurate kits for fast and early detection of apoptosis. However, their sensitivity and reliability have often been scrutinized. Here we introduce a rapid and improved method of DNA ladder apoptosis assay for evaluating apoptosis in mammalian cells. NIH-3T3 cell line was used in this study. After treatment of cells with apoptotic agent, 500 μM H2O2 at 48 hours, DNA was extracted. Then an update protocol of DNA ladder assay was applied for detection of apoptosis. Flow cytometry and DAPI staining were performed to verify apoptosis. Primary and late apoptosis in the H2O2-treated cells was determined by flow cytometry analysis. DAPI Staining used to show DNA damage and DNA ladder assay using 1.5% gel electrophoresis showed fragmentation in the DNA of treated cells. In this research we aimed to improve DNA ladder assay to the high quality detection of apoptosis in mammalian cells. In our strategy, employing a practical DNA extraction protocol, DNA ladder assay could be applied as an easy/fast method for apoptosis detection. This improved method is able to detect apoptosis in a cost effective/timely manner without need for commercial kits and special equipment.
According to outcomes from clinical studies, an intricate relationship occurs between the beneficial microbiota, gut homeostasis, and the host’s health status. Numerous studies have confirmed the health-promoting effects of probiotics, particularly in gastrointestinal diseases. On the other hand, the safety issues regarding the consumption of some probiotics are still a matter of debate, thus to overcome the problems related to the application of live probiotic cells in terms of clinical, technological, and economic aspects, microbial-derived biomolecules (postbiotics) were introducing as a potential alternative agent. Presently scientific literature confirms that the postbiotic components can be used as promising tools for both prevention and treatment strategies in gastrointestinal disorders with less undesirable side-effects, particularly in infants and children. Future head-to-head trials are required to distinguish appropriate strains of parent cells, optimal dosages of postbiotics, and assessment of the cost-effectiveness of postbiotics compared to alternative drugs. This review provides an overview of the concept and safety issues regarding postbiotics, with emphasis on their biological role in the treatment of some important gastrointestinal disorders.