bleb

1. (pathology) A large vesicle or bulla, usually containing a serous fluid.Examples: "2008, Lin Her-Shyuan Lin, Adam C, Reynolds, 180: Filtering Blebs and Associated Problems, Frederick Hampton Roy, Frederick W. Fraunfelder, Frederick T. Fraunfelder (editors), Roy and Fraunfelder's Current Ocular Therapy, 6th Edition, page 340, Inflammation and scarring is a shared mechanism for chemical irritants, cryotherapy, laser thermotherapy, and autologous blood injection in the treatment of bleb dysesthesia, overfiltering blebs, and bleb leaks."; "2009, Anthony Wells, Tina Wong, Jonathan G. Crowston, 79: Tenon's Cyst Formation, Wound Healing, and Bleb Evaluation: Part A: Tenon's Cyst Formation and Management, Tarek M. Shaawary, Mark B. Sherwood, Roger A. Hitchings, Jonathan G. Drowston (editors), Glaucoma, Volume 2: Surgical Management, page 236, If the leak allows bulk flow of aqueous, the rest of the bleb can collapse, allowing apposition of the inflamed inner bleb walls, which are likely to adhere. If such adherence is over most or all of the bleb area, bleb failure is probably inevitable."; "Use of intraoperative antimetabolites is a risk factor for the development of a bleb leak. The mechanism of a bleb leak is thought to be as follows. Ischemic blebs are stretched and surrounded by heavily scarred tissue, which limits the ability of the aqueous to flow beyond the scarred tissue. The bleb expands locally, producing a tractional hole when the tissue overreaches its maximal stretch."Synonyms: blister

2. (cytology) An irregular bulge in the plasma membrane of a cell undergoing apoptosis.Examples: "Figure 4.20 reveals blebs on the surface of a bacterial cell. In many instances, these blebs are released from the cell into the surrounding media."; "2013, Louis Foucard, Xavier Espinet, Eduard Benet, Franck J. Vernerey, The Role of the Cortical Membrane in Cell Mechanics: Model and Simulation, Shaofan Li, Dong Qian (editors), Multiscale Simulations and Mechanics of Biological Materials, page 261, As the bleb grows (the growth time is on order of a minute), the actin cortex starts reassembling beneath the bleb membrane."; "A different approach is to use protrusions from the membrane, which are called blebs or blisters.[…]The absence of actin and tubulin from blebs formed on oocytes of Xenopus laevus clearly indicates the bleb membrane is detached from the cell cytoskeleton (Figure 3.29)."

3. (geology) A bubble-like inclusion of one mineral within another.Examples: "1974, George E. Stoertz, George E. Ericksen, Geology of Salars in Northern Chile, Geological Survey Professional Paper 811, page 32, Figure 23. […] The crust is underlain by silty sand, which is loosely cemented by a meshwork of gypsum crystals and contains blebs and small nodules of white ulexite (U)."