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[IP] 4 abstracts from medline re: pumps

Nippon Rinsho 1999 Mar;57(3):719-25=20

[Design and development strategy for wearable and implantable artificial=20
endocrine pancreas].
[Article in Japanese]=20
Shichiri M, Nishida K

Department of Metabolic Medicine, Kumamoto University School of=20

[Medline record in process]

The ultimate goal of development of an artificial endocrine pancreas is=20
for long-term strict glycemic control, and therefore, the trend in=20
development is now from bedside-type to wearable- or implantable-type.=20
With either a miniaturized extracorporeal glucose monitoring system=20
based on microdialysis sampling method or a ferrocene-mediated=20
needle-type glucose sensor covered with highly biocompatible membrane,=20
and with subcutaneous insulin infusion algorithm using short-acting=20
insulin analogue, long-term physiological glycemic control could be=20
obtained by wearable artificial endocrine panceras. The next step will=20
be directed to the implantable one. Non-invasive infrared absorbance=20
spectroscopy to fit into an artificial tooth prosthesis, an implantable=20
artificial endocrine pancreas, in which measured glucose concentrations=20
are transmitted telemetrically to implanted computer and pump system,=20
might be developed.=20

PMID: 10199159, UI: 99215372 -
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Pharmacol Ther 1999 Jan;81(1):37-51=20

Pharmacological management of diabetes: recent progress and future=20
perspective in daily drug treatment.

Emilien G, Maloteaux JM, Ponchon M

Laboratory of Pharmacology, Universite Catholique de Louvain, Brussels,=20

[Medline record in process]

Glycaemic control in Type 1 diabetes has been proven efficient in=20
preventing microvascular and neurological complications. The assumption=20
that good control of hyperglycaemia may also have significant impact on=20
alleviation of complications in Type 2 diabetes has gained growing=20
support in recent years. Measures such as body weight reduction and=20
exercise improve the metabolic defects, but pharmacological therapy is=20
most frequently used. The sulphonylureas stimulate insulin secretion.=20
Metformin and troglitazone increase glucose disposal and decrease=20
hepatic glucose output without causing hypoglycaemia. Acarbose helps to=20
spread the dietary carbohydrate challenge to endogenous insulin over=20
time. These pharmacological treatments can improve blood glucose=20
regulation in Type 2 diabetes patients. However, the key to strict=20
glycaemic control with use of exogenous insulin lies in the creation of=20
delivery methods that emulate physiologic insulin secretion. Insulin=20
lispro, a recombinant insulin analogue, is identical to human insulin=20
except for the transposition of proline and lysine at positions 28 and=20
29 in the C-terminus of the B chain. Evidence suggests that patients=20
perceive their quality of life to be improved with insulin lispro when=20
compared with regular human insulin, and that satisfaction with=20
treatment is greater with the insulin analogue. Numerous new=20
pharmacological approaches are under active investigation, with the aim=20
of promoting insulin secretion, improving the action of insulin, or=20
slowing carbohydrate absorption. With respect to continuous subcutaneous=20
insulin infusion therapy and implantable pumps, despite that this=20
approach is not widely utilised, it appears to bring us as close to=20
achieving glycaemic control as is feasible with current treatment=20
approaches. However, general application of such technology requires=20
significant improvements in several areas, such as improvement of=20
patency of catheter, pump failures due to early battery depletion=20
incidents, and pump miniaturisation. Future perspective resides on=20
insulin analogues with longer half-lives that would provide better basal=20
insulin coverage in association with fast-acting analogues.=20

PMID: 10051177, UI: 99158486=20
- ---------------------------------------------------------
IEEE Trans Biomed Eng 1999 Feb;46(2):148-57=20

A model-based algorithm for blood glucose control in type I diabetic=20

Parker RS, Doyle FJ 3rd, Peppas NA

Department of Chemical Engineering, University of Delaware, Newark=20
19716, USA.=20

A model-based predictive control algorithm is developed to maintain=20
normoglycemia in the Type I diabetic patient using a closed-loop insulin=20
infusion pump. Utilizing compartmental modeling techniques, a=20
fundamental model of the diabetic patient is constructed. The resulting=20
nineteenth-order nonlinear pharmacokinetic-pharmacodynamic=20
representation is used in controller synthesis. Linear identification of=20
an input-output model from noisy patient data is performed by filtering=20
the impulse-response coefficients via projection onto the Laguerre=20
basis. A linear model predictive controller is developed using the=20
identified step response model. Controller performance for unmeasured=20
disturbance rejection (50 g oral glucose tolerance test) is examined.=20
Glucose setpoint tracking performance is improved by designing a second=20
controller which substitutes a more detailed internal model including=20
state-estimation and a Kalman filter for the input-output=20
representation. The state-estimating controller maintains glucose within=20
15 mg/dl of the setpoint in the presence of measurement noise. Under=20
noise-free conditions, the model-based predictive controller using state=20
estimation outperforms an internal model controller from literature=20
(49.4% reduction in undershoot and 45.7% reduction in settling time).=20
These results demonstrate the potential use of predictive algorithms for=20
blood glucose control in an insulin infusion pump.=20

PMID: 9932336, UI: 99131128=20
- ----------------------------------------------------------
Am J Surg 1998 Dec;176(6):622-6=20
Surgical experience with implantable insulin pumps. Department of=20
Veterans Affairs Implantable Insulin Pump Study Group.

Thompson JS, Duckworth WC, Saudek CD, Giobbie-Hurder A

Omaha Veterans Affairs Medical Center, Nebraska, USA.=20

BACKGROUND: A recent Veterans Affairs cooperative trial demonstrated=20
that intensive insulin therapy via an implantable pump with=20
intraperitoneal insulin delivery reduced glycemic variability and=20
improved quality of life compared with multiple daily insulin=20
injections. Our aim was to determine perioperative morbidity and assess=20
long-term function of the implantable insulin pump. METHODS: Fifty-one=20
adult patients with type 2 diabetes had infusion pumps placed over a=20
2-year period at seven VA Medical Centers as part of a randomized=20
prospective study. RESULTS: All pumps were placed successfully. There=20
were two (4%) perioperative complications. There were no wound=20
complications. Duration of pump use ranged from 12 to 25 months (mean=20
20). Catheter obstruction (57%) and pump malfunction (25%) were the most=20
common reasons for pump explantation. Catheter occlusions increased=20
after 12 months. Catheter occlusion was treated by percutaneous rinse=20
procedure in 75% and revisional procedures in 31% of patients.=20
CONCLUSIONS: Implantable insulin pumps can be placed with minimal=20
surgical morbidity. Attention to surgical detail and infusion protocol=20
permits satisfactory long-term function. Pump/catheter complications=20
increase with time but are usually resolvable by either operative or=20
percutaneous manipulations.=20

Publication Types:
=95Clinical trial =95Randomized controlled trial=20

PMID: 9926802, UI: 99123992=20
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