Scaffoldings, temporary

Polymer hydrogels consist of a cross-finked network of hydrophilic polymers with a very large water content (up to 99%) (Wichterle and Lim, 1960).They are structurally similar to the ECM and have therefore frequently been used as ECM mimics (Fedorovich et al., 2007 Shoichet, 2010). Other biological applications include the use as injectable scaffolds, (temporary) cell culture supports and drug delivery matrices (Mano, 2008). For all these applications, the introduction of enzyme-responsive functionalities into the polymer hydrogel is attractive because it would either more closely mimic the ECM (which is itself enzyme responsive) or allow drug delivery in response to the presence of a specific enzyme. 

Unsecured objects, such as bricks and gas cylinders, near the edges of elevated surfaces, such as catwalks, roof tops, and scaffolding, which may dislodge and fall on workers Debris and weeds that obstruct visibility Install skid-resistant strips and other antiskid devices on slippery surfaces Construct operation pads for mobile facilities and temporary structures Construct loading docks, processing and staging areas, and decontamination pads... 

There are many engineering and biological principles which must be taken into account when designing scaffolds for cell transplantation. Some are peculiar to the specific application while others are essential requirements which must be observed for all organs. The primary role of a scaffold is to provide a temporary... 

Artificial biologies, whelher soff or hard, can be categorized as eifher temporary (short term) or permanent (long term) in their intended application. Most, but certainly not all, polymers for biomedical applications are of the short-term type and include sutures, drug delivery devices, temporary vascular grafts and stents, tissue scaffolds. 

This chapter will review current activities and proposed research related to the development of artificial organs and organ-assist devices. While we will focus on the human liver, the discussion is applicable to other organs. The pancreas and the endocrine functions of the kidney follow the same basic path — the culturing of cells on a scaffold. The cells, of course, must function as they do in a natural uncompromised slate while the scaffold provides a permanent or temporary template on which the cells attach and proliferate. 

While the scaffold is the structure upon which the hepatic cells must congregate, it must be constituted from a minimum amount of material. The device must be able to contain the hepatic spheroids that are in a constant state of flux and allow for blood to pass through in physiological conditions without channeling or other diminution of effective surface area. We will describe the concept of pseudovasculature that depends on a scaffold with a very large void volume. The use of pseudovasculature is intended as a temporary measure until natural vasculature develops. 

Early reports of the biomedical use of poly(lactic acid) date back to the 1960s [3, 175]. Since then, PLA has gained widespread application in the medical field, for use in sutures [8], drug delivery devices [15, 17, 24, 59-90], prosthetics, scaffolds, vascular grafts, and bone screws, pins and plates for temporary internal fracture fixation [10-13]. Good mechanical properties and the fact that it de-... 

One reactor had been removed for repairs, and the resulting gap was bridged by a temporary 20-in. pipe, connected by a bellows at each end and supported on temporary scaffolding. Tliis pipe collapsed, and in tlic minute or so that elapsed before ignition, about 35 tons of cyclohexane escaped. The extensive damage tliat occurred could liave resulted from tlie deflagration of as little as 10 to 20 tons. 

In this reaction there was also no necessity to resort to a high-dilution technique. The temporary covalent binding of the multidentate ligand around the central boron atom served as a scaffold to create an intermediate structure with the geometry required to form selectively the desired product. Later we will see examples that illustrate the breadth to which coordination around a central atom or ion is applied as a powerful tool to ensure pre-organization of the substrates. 

Providing continuous clean-up of the construction area. Removing excess materials, temporary facilities, and scaffolding. 

Erbel R, Di Mario C, Bartunek J, et al. Temporary scaffolding of coronary arteries with bioabsorbable magnesium stents a prospective, non-randomised multicentre trial. Lancet 2007 369(9576) 869-75. 

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