Pancreas artificial

In terms of membrane area used and doUar value of the membrane produced, artificial kidneys are the single largest appHcation of membranes. Similar hoUow-fiber devices are being explored for other medical uses, including an artificial pancreas, in which islets of Langerhans supply insulin to diabetic patients, or an artificial Uver, in which adsorbent materials remove bUinibin and other toxins. 

K Burczak, T Fujisato, M Hatada, Y Ikada. Protein permeation through polymer membranes for hybrid-type artificial pancreas. Proc Jpn Acad B 67 83-88, 1991. 

A. Albisser, B. Lebel, G. Ewart, Z. Davidovac, C. Botz, and W. Zingg, Clinical control of diabetes by artificial pancreas. Diabetes 23, 397-404 (1974). 

Keywords Bio artificial pancreas, biomaterials, complex coacervation, immunoisolation, microencapsulation, polyelectrolytes, water soluble polymers. 

The closed-loop system (often termed the artificial pancreas ) is essentially a more sophisticated version of the system described above. It consists not only of a pump and infusion device, but also of an integral glucose sensor and computer that analyses the blood glucose data obtained and adjusts the flow rate accordingly. The true potential of such systems remains to be assessed. 

In the biomedical area, SPHs and SPH composites can be used to make various biomedical devices, such as artificial pancreas, artificial cornea, and artihcial skin, articular cartilage, soft tissue substitutes, cell growth substrates in tissue engineering, burn dressings, surgical augmentation of the female breast, or hemoperfusion in blood detoxification and in the treatment of uremia. 

Present perfect-passive An artificial pancreas has been developed. (From Tyon, 2000)... 

Other recently developed biomaterials will be used for quite different purposes in tissue engineering such as artificial pancreas and liver, artificial skin, nerve regeneration, gene therapy vascular grafts, cornea replacement and others.3... 

Development of Subcutaneous-Type Glucose Sensors for Implantable or Portable Artificial Pancreas... 

The closed-loop type artificial pancreas (specifically 8-cell), which consists of an automatic continuous monitor of blood glucose level (BGL) and an automatic injector of insulin which are coupled with feed-back system, has great potential for prevention of diabetic complication such as micro-angiopathies(l). A large-scale closed-loop type artificial pancreas for bedside use has already been developed and is clinically used at some laboratories and hospitals (2-4). However, this device is limited to only bedside use. On the other hand, the open-loop type artificial pancreas which consists of only a insulin injecting pump without an automatic continuous monitor of BGL, has been developed and is going to be clinically used(5-7). This system, however, can not completely control BGL as well as the bare pancreas in a normal body and often causes lower BGL(8-9). 

In order to provide for the complete therapy of diabetic patients, an implantable or portable closed-loop type artificial pancreas must be developed. The key factor in the development of such system is development of a small-size glucose sensor which is able to measure directly up to 500-700 mg/dl of BGL in a blood stream or in a body fluid. 

About ten years ago, Bessman et al(10), University of Southern California, developed a glucose sensor of enzyme electrode type with glucose oxidase (G0X) for an artificial pancreas. This sensor had... 

In vivo tests. The response properties of the glucose sensors I to IV are summarized in Table 1. The sensor HI and W have more desirable responses than the sensor I and H as a glucose sensor for the artificial pancreas. In the present paper, however, the results of in vivo tests obtained by using the sensor I will be demonstrated in the later section. 

Glucose sensor IH and W have more desirable properties than that of the sensor I, so that they are promising as a subcutaneous type glucose sensor for an implantable artificial pancreas. Now, life time test and in vivo testing of these sensors are going to be performed, and the results of these tests will be reported in the future. 

Burczak K, Gamian E, Kochman A. Long-term in vivo performance and biocompatibility of poly(vinyl alcohol) hydrogel macrocapsules for hybrid-type artificial pancreas. Biomaterials 1996, 17, 2351-2356. 

On the commercial front, an artificial liver system has reached advanced clinical trial stage. Based on pig hep-atocytes immobilized in a hollow-fiber membrane module, this system provides temporary life support until a liver from a human donor is available for transplantation (Fig. 50). Also under development is an artificial pancreas intended as a permanent replacement of the native organ (Fig. 51). 

FIGURE 51 Schematic of artificial pancreas under development based on a membrane unit (Circe Biomedical, Inc., Lexington, MA). 

Kim SW and Jacobs HA. Self-regulated insuhn dehvery—artificial pancreas. Drug Development and Industrial Pharmacy 1994 20 575-580. 

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