If the cells are now confined in mesoscopic microprinted circular domains, the system evolves toward a configuration where two identical disclinations face each other along a diameter. When confined in infinite stripes, cells align with the physical boundaries and expel the defects, therefore they eventually define perfectly oriented domains over the width of the stripes that can reach half a millimeter. Monitoring closely the behavior of the defects in in vitro cultures shows that these active cellular nematics operate in a regime where activity is effectively damped by cell-substrate friction. As with liquid crystals, these defects of orientation may be used to probe the behavior of the active nematic cellular systems. The domains in which cells are perfectly oriented are prevented from fusing together only by the presence of defects of orientation that are intrinsic to such structures. However, the regime in which live spindle-shaped cells operate remained largely unexplored. Active non-cellular nematics are generally dominated by activity, yielding complex chaotic movements and flows.
However, unlike conventional liquid crystals, cells are active entities and this supracellular organization is best described as an “active nematic”. In the terminology of liquid crystals, such an organization is called a “nematic” organization. When plated on a plane surface, they define domains of common orientation whose size is large compared to a cell size. Most spindle-shaped cells such the ones constituting muscles, but also sarcomas, routinely self-organize by aligning together along a common direction. Joanny ( Physical Approach of Biological Problems) (CNRS/UPMC/Institut Curie) use the physics of Liquid Crystals to understand the dynamics of this organization. Silberzan ( Biology-Inspired Physics at Mesoscales) and J.-F. Pathologists often use additional tests such as immunohistochemistry to help them reach a more complete and final diagnosis.Ī cancerous tumour may be called a malignant spindle cell neoplasm until a more complete diagnosis can be reached with the help of additional tests or additional tissue to examine.In a letter published in Nature Physics, the groups of P. This is usually a descriptive or preliminary diagnosis that will be changed once more information is available. Your pathology report may describe a tumour that is made up almost entirely of spindle cells simply as a spindle cell neoplasm or tumour. Another type of cancer called a carcinoma can also be made up of these cells and in this case the pathologist may describe the cells as sarcomatoid. Most cancers made up of spindle cells are called sarcomas. The type of tumour depends on the location in the body and the way the cells look when examined under the microscope.
These tumours can be either benign (non-cancerous) or malignant (cancerous). Some tumours are made up almost entirely of spindle cells. Fibroblasts are support cells that are found in a type of connective tissue called stroma. The most common type of normal spindle cell is called a fibroblast.
They are found both in normal, healthy tissue and in tumours. Spindle cells are specialized cells that are longer than they are wide.
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