Tissue tethering

Blanco and Samadani37 obtained a patent for the construction of a microprosessor-based insulin pump that works in a similar fashion to the Biostator. The implantable infusion device consists of a catheter, an information-transmitting sensor located in the catheter, a microprocessor, a pump, the drug reservoir, and a power source. The pump, the sensor, and the valves are connected by appropriate leads to the microprocessor. The device is implanted in the subcutaneous tissue in the chest area, and the infusion catheter is tethered intravenously to a central location, such as the right atrium. The device is inserted with the inlet port facing outward so that it may be refilled periodically by a physician. 

The Premere PFO occluder (Fig. 7) is another selfexpanding double disc device specifically designed for PFO closure. The right-sided anchor is constructed of nitinol between two layers of knitted polyester fabric connected by a flexible polyester braided tether to the left atrial anchor. The left atrial anchor consists of four radiating arms without polyester layers to improve tissue absorption and to minimize thrombus formation. Since the distance between the anchors... 

The structures of three cytokine receptor C2HRs and tissue factor (TF) have been determined (see Table I and Chill et al., 2003 Harlos et at, 1994 Josephson et al, 2001 Randal and Kossiakoff, 2001 Thiel et al., 2000 Walter et al, 1995). The general features of the C2HR are shown in Fig. 8. It consists of two /3-sandwich domains, D1 and D2, connected by a short linker containing 1 turn of a- or 3io helix. The cytokine binding site is comprised predominantly of the loops located at the D1 and D2 interface. The N-terminal D1 domain is most distal from the cell membrane, while the G-terminal D2 domain is followed by a short tether of 5-12 amino acids in length before the beginning of the transmembrane helix. 

The inflammatory response is initiated by stimuli released from sites of tissue injury that results in the expression of selectins on the endothelial layer. These selectins (E(endothelial)-selectin and P(platelet)-selectin) function through recognition of oligosaccharides on the opposing leukocyte cell surface [194]. This interaction eventually weakly tethers the leukocyte to the endothelial layer, at which point integrin binding events lead to firm adhesion and extravasation of the leukocyte into the tissue. In certain disease processes, excessive leukoc)4e infiltration becomes deleterious to the body, and inhibitors of this process are desirable. Rheumatoid arthritis, asthma, organ transplant rejection, and reperfusion injury are just a few of the cases in which these events occur [27]. 

In the organism, HA occurs in many diverse forms, circulating freely, decorated with a variety of HA-binding proteins (hyaladherins), tissue-associated, intercolated into the ECM by electrostatic or covalent binding to other matrix molecules. It comprises a major portion of the intimate glycocalyx that surrounds all cells. HA can be tethered to cell surfaces by any of a number of membrane-associated receptors. Recent evidence indicates that HA also exists within cells, though little is known of the form or function of such HA. 

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