RESUMEN
Biofilms are surface-attached complex aggregates consisting of bacteria cells and extracellular polymeric substances. Cells in biofilms show strong resistance to antibiotics and immune-escape capabilities. Their motility and metabolic activities are quite different from those when they are in planktonic style. In recent years, applications of new image-capturing techniques together with new image-processing methods, have greatly advanced the development of bacterial studies. This review focuses on bacterial tracking techniques. We first present an overview of recent progress in applications of those techniques in biofilm research, especially in the areas of bacterial motility and biofilm regulation, including swimming, twitching, swarming and typical regulatory signaling pathways for biofilms. Then we give a prospect for future applications of bacterial tracking in other related microbial fields.
RESUMEN
The quantitative analysis of biomechanical profiles at the single-cell level can provide additional information. It is usually not available in traditional cell biology approaches, but may be crucial to assess and understand tumor prognosis and response to chemotherapy. In this study, the on-line changes of cell elastic properties after the addition of cancer target drug LHRH-PE40 were monitored by atomic force microscopy ( AFM) on living HeLa cell surface under physiological condition. The results from AFM based force spectroscopy showed that LHRH-PE40 induced a distinct increase of the cell surface elasticity of HeLa cells. The fluorescence images implied that the target drug LHRH-PE40 would affect the re-organization of cell actions, which led to the increase of the elasticity of HeLa cells.