摘要:

Since the first appreciation of the role of the pancreas in diabetes, investigators have tried to replace the function of the insulin-producing β cells. Because type I diabetes is caused by autoimmune destruction of these β cells, transplanting islets is attractive, although somewhat elusive. Rodent islet transplants were performed in the 1970s, but the application to humans required many advances that spanned a decade. Even after the methods for the automated large-scale isolation of the number and quality of cells required for human investigation were available, it was not until 1990 that the first successful human islet allografts were reported. Human islet autografts were increasingly successful during this period, giving hope for successes with allografts. Long-term results of euglycemia with islet autografts and allografts have now established the feasibility of islet transplantation in humans. Although there are many clear advantages to cellular transplants compared with whole-organ transplants, the success rate is currently unacceptably low because of rejection. Recent developments in the field of organ acceptance and tolerance and the successful use of barrier devices in large animals and recently in humans to protect islet grafts provide real hope that more widespread application of islet transplantation in healthy patients may be possible.

ISSN:1068-3097    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

A continuous glucose monitor a microprocessor, and an insulin delivery system are the three essential features of a mechanical artificial pancreas. Significant lag time in equilibration between blood and subcutaneous glucose concentrations is a significant factor that may limit the ability of an artificial pancreas to maintain normoglycemia, particularly after meals. Delay in onset of action of subcutaneously administered insulin, due to slow absorption, is another limiting factor, but it may be overcome by development of bioengineered insulins that are more rapidly absorbed. Needle-type glucose sensors are hampered by variability in sensor sensitivity and short half-life, requiring frequent recalibrationin vivo. Perfusion-dialysis based electrodes are less sensitive to interfering substances and may be more stablein vivo. Measurement of glucose noninvasively by near-infrared absorption spectroscopy appears feasible, and prototype instruments have been developed.

ISSN:1068-3097    

出版商:OVID    

年代:1995

数据来源: OVID