Search results for "Islet"
showing 10 items of 98 documents
Multi-Criteria Decision Making support system for pancreatic islet transplantation
2011
Pancreatic islet transplantation consists of replacing insulin-producing cells to restore normal glycemia in diabetic patients. This is a minimal invasive procedure that has been proved successful. Unfortunately unpredictability of islet transplant outcome remains a frustrating and costly issue limiting the clinical implementation of this procedure. Multiple variables are involved in the procedure and assessment is subjective to individual operators. The aim of this study was to generate a system expressing the probability of transplant success in relation to four classes of identified variables (donor, organ, isolation and recipient). We have proposed the utilization of Multi-Criteria Deci…
Encapsulation of Langerhans' islets: Microtechnological developments for transplantation
2011
There is an increasing trend to apply microsystems and microfluidics to solve medical and biomedical tasks. Microfluidic modules are used to modify and manipulate cells and cell clusters for therapeutic applications. Specifically, a method and technical system for encapsulation of Langerhans' islets as an option for the future treatment of diabetes mellitus is described. Type-1 diabetes patients suffer from an absolute lack of the hormone insulin caused by an autoimmune process destroying the Langerhans' islets. One way to restore glucose-dependent insulin secretion is the transplantation of human pancreatic islet cells (85% beta cells) from cadaveric donors. However, to prevent the rejecti…
Polymorphism of Amyloid Fibrils and their Complexes with Catalase
2014
Catalase binding to amyloid fibrils has been shown for the Alzheimer’s amyloid-β (Aβ), type 2 diabetes-associated islet amyloid polypeptide (IAPP) and Creutzfeldt-Jakob disease-associated prion protein (PrP). Catalase targets a specific domain with a GAII-like sequence and there are a number of other amyloid fibril-forming proteins that contain related sequences, such as the Parkinson’s associated α-synuclein protein and the Huntington disease protein Huntingtin. Using transmission electron microscopy (TEM) analysis, interactions show specific binding of catalase to some, but not all, fibrillar forms of Aβ, IAPP and PrP fragments, allowing determination of the fibrillar forms that contain a…
Cell Therapy in Type 1 Diabetes
2011
The incidence of diabetes mellitus has grown exponentially in the last few years. Etiopathogenesis of diabetes implies a ?-cells damage in the islet of Langerhans, either through an autoimmune reaction present in type 1 diabetic patients or through altered function within these cells that affect their ability to secrete a properly functioning insulin hormone, in patients suffering from type 2 diabetes. Exogenous insulin supply is, at the moment, the therapy of choice of the disease but it does not allow tight control of glucose regulation, leading to long-term complications. Over the past few decades, pancreas or pancreas-kidney organ transplantation has been the most effective treatment fo…
Role of ghrelin and leptin in the regulation of carbohydrate metabolism. Part I. Ghrelin
2012
Grelina jest polipeptydem wydzielanym przez komórki wydzielnicze błony śluzowej żołądka i jelit, jądro łukowate podwzgórza, a także przez komórki epsilon (e), które znajdują się w obrębie wysp trzustkowych. Grelina odgrywa ważną rolę w utrzymywaniu homeostazy energetycznej organizmu oraz wpływa na wewnątrzwydzielniczą funkcję trzustki i metabolizm glukozy. W regulacji homeostazy glukozy grelina bierze udział poprzez modulację wydzielania isuliny, jak i wrażliwości na insulinę. Wobec różnorodnych biologicznych skutków działania greliny, obecne badania poświęca się potencjalnym możliwościom ich modyfikowania. Dużo uwagi skupiono wokół enzymu zwanego O-acylo transferazą greliny (ghrelin O-acyl…
3D Collagen matrix improves islets of Langerhans differentiation and function
2014
The importance of preserve cell-cell contact and cell-matrix interaction are both fundamental for maintain the differentiation state. We use both standardized method of isolation and culture in 3D matrix which improves islet cell survival and function for more than one week in colture.
Alginate encapsulation improves viability and integrity of cryopreserved pancreatic islets and multicellular spheroids: combined fluorescence, scanni…
2007
Extended abstract of a paper presented at MC 2007, 33rd DGE Conference in Saarbrücken, Germany, September 2 – September 7, 2007
Pancreatic islets from non-heart beating donor pig: Two-layer preservation method in an in vitro porcine model
2011
Purpose Pancreata from non-heart beating donors could represent an unlimited source of islets if their cell viability can be efficiently preserved during the time necessary to process the organs by the use of a better solution of preservation compared to the classic University of Wisconsin solution. The aim of this study was to determine whether it is possible to obtain functioning “alive islets” from non-heart-beating donors by comparing, on a porcine model, the classic “UW ice-store” method with a two-layer cold storage method (TLM) using oxygenated Perfluorocarbons (PFC) and UW. Methods Whole pancreata were harvested from 20 NHBDs female pigs with similar characteristics and preserved fo…
Isolation and colture of beta-like cells from porcine Wirsung duct
2009
We sought to develop a protocol to isolate and culture porcine Wirsung duct cells in order to determine their potency to differentiate into insulin-expressing beta-like cells. The porcine Wirsung duct isolated by a surgical microdissection was digested with collagenase P and trypsin to dissociate ductal cells. These elements were cultured in serum-free supplemented media: for 2 weeks. Thereafter the cells were exposed to varying concentrations of glucose (0, 5.6, 17.8, and 25 mmol/L) to induce a beta-like phenotype, as identified by immunohistochemical staining. Cell growth proceeded slowly for the first 2 weeks of culture. After glucose induction for 2 weeks, they formed pancreatic islet-l…
Diabetes Antibody Standardization Program: evaluation of assays for autoantibodies to glutamic acid decarboxylase and islet antigen-2
2008
Aims/hypothesis Islet autoantibodies are important in diabetes classification and risk assessment, and as endpoints in observational studies. The Diabetes Autoantibody Standardization Program (DASP) aims to improve and standardise measurement of autoantibodies associated with type 1 diabetes. We report results for glutamic acid decarboxylase autoantibodies (GADA) and islet antigen-2 autoantibodies (IA-2A) from three DASP workshops (2002–2005). Methods Up to 60 laboratories in 18 countries participated in each workshop. Participants received coded serum aliquots from 50 patients with newly diagnosed type 1 diabetes (median age 18 years, range 9–35 years) and 100 blood donor controls. Results…