16 research outputs found
A Description of Clinician Reported Diagnosis of Type 2 Diabetes and Other Non-Type 1 Diabetes Included in a Large International Multicentered Pediatric Diabetes Registry (SWEET)
Although type 1 diabetes (T1D) remains the most frequent form of diabetes in individuals aged less than 20 years at onset, other forms of diabetes are being increasingly recognized.info:eu-repo/semantics/publishedVersio
Prediction of glucose profile in children with type 1 diabetes mellitus using continuous glucose monitors and insulin pumps
Porcine islet function: effects of arginine, leucine, and butyrate
[abstract non disponibile
Saliva proteomics analysis offers insights on type 1 diabetes pathology in a pediatric population
The composition of the salivary proteome is affected by pathological conditions. We analyzed by high resolution mass spectrometry approaches saliva samples collected from children and adolescents with type 1 diabetes and healthy controls. The list of more than 2000 high confidence protein identifications constitutes a comprehensive characterization of the salivary proteome. Patients with good glycemic regulation and healthy individuals have comparable proteomic profiles. In contrast, a significant number of differentially expressed proteins were identified in the saliva of patients with poor glycemic regulation compared to patients with good glycemic control and healthy children. These proteins are involved in biological processes relevant to diabetic pathology such as endothelial damage and inflammation. Moreover, a putative preventive therapeutic approach was identified based on bioinformatic analysis of the deregulated salivary proteins. Thus, thorough characterization of saliva proteins in diabetic pediatric patients established a connection between molecular changes and disease pathology. This proteomic and bioinformatic approach highlights the potential of salivary diagnostics in diabetes pathology and opens the way for preventive treatment of the disease. © 2018 Pappa, Vastardis, Mermelekas, Gerasimidi-Vazeou, Zoidakis and Vougas
Tissue polypeptide-specific antigen serum concentrations in children, adolescents, and young adults with type 1 diabetes
Automated large-scale isolation, in vitro function and xenotransplantation of porcine islets of Langerhans
Abstract: To evaluate the potential of utilizing porcine islet tissue as an alternative to human islet tissue for transplantation, we developed a method for the isolation of large amounts of highly purified porcine islets, and assessed the in vitro and in vivo function of the isolated islets after 1, 4, and 7 days of culture. The pancreatic duct of the splenic lobe was cannulated and distended by, injection of Hanks' balanced salt solution containing 1.5 mg/ml collagenase. The pancreas was then processed by a modification of the automated digestion-filtration method developed in this laboratory, and with purification accomplished by Euro-Ficoll gradients (dialyzed Ficoll in Eurocollins solution), consisting of two layers of 1.108 and 1.091 g/cm3 density, topped with a layer of HBSS. The postpurification yield was 5203 +/- 645 (mean +/- SEM) islets per gram of pancreas with a number of islet equivalents (IE) per gram pancreas (islet equivalence: 150-mu-m-sized islets) of 3551 +/- 305, and a volume of 6.27 +/- 1.7 mm3 islet tissue per gram of pancreas. The islet purity exceeded 90%. Overnight-cultured, perifused porcine islets released 53.1 +/- 8.2 pM insulin/200 IE at 3.3 mM glucose, and 114.9 +/- 25.4 p.M insulin/200 IE at 16.7 mM glucose (P < 0.001 vs. basal output). When theophylline was added, insulin secretion increased to 264.2 +/- 63.2 pM/200 IE (P < 0.001 vs. basal secretion and P < 0.005 vs. secretion at 16.7 mM glucose). After 4 days of culture, the islets still responded to secretagogues. The functional integrity of the isolated islets was confirmed by reversal of diabetes in aL3T4 antibody-treated C57B/B6 diabetic mice: normoglycemia was promptly restored by transplanting 1000 over-night- or 7-day-cultured (24-degrees-C) islets under the kidney capsule. These results suggest that continued improvements of porcine islet isolation and culture could permit the use of porcine islets in immunoalteration and immunoisolation studies that may lead to eventual human transplantation
In vitro function and xenotransplantation of long-term (3 weeks) cultured porcine islets of Langerhans
[abstract non disponibile
Prevention of contamination of isolated porcine islets of Langerhans
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Cryogenic storage of isolated, purified porcine pancreatic islets
Abstract: Highly purified islets of Langerhans were prepared in the present study from adult pigs by collagenase digestion and density gradient purification. After overnight culture, the tissue was equilibrated with DMSO at 25 degrees C, supercooled to -7.5 degrees C, nucleated, slowly cooled at 0.25 degrees C/min to -40 degrees C, and stored at -130 degrees C. Then, after variable periods of storage, the islets were rapidly thawed at 37 degrees C. Postthaw actual islet and islet equivalent (150-mu m sized islets) recovery were 75+/-7% and 66+/-4%, respectively. The frozen-thawed porcine islets maintained good morphology on histological staining by hematoxylin-eosin and aldehyde-fuchsin. Upon perifusion, basal insulin secretion was 43+/-10 and 67+/-18 pmol/L from noncryopreserved, control islets, and cryopreserved islets, respectively (P=0.2). Peak insulin release at 16.7 mmol/L glucose was 85+/-28 pmol/L from noncryopreserved islets and 157+/-48 pmol/L from the frozen-thawed islets (P=0.1). When 10 mmol/L theophylline was added to 16.7 mmol/L glucose, the secretion of the hormone peaked to 221+/-83 (control islets) and 479+/-140 pmol/L (cryopreserved islets, P=0.1). Total insulin secretion differed significantly for the noncryopreserved and the cryopreserved islets at both 16.7 mmol/L (1412+/-306 vs. 3756+/-764 pmol/L, respectively, P=0.007) and 16.7 mmol/L glucose plus 10 mmol/L theophylline (2161+/-371 vs. 7505+/-2075 pmol/L, respectively, P=0.011). Normoglycemia was restored within 7 days from implantation in temporarily immunosuppressed (aL3T4 antibody) mice with streptozotocin-induced diabetes by transplanting 1500-2000 cryopreserved porcine islets under the kidney capsule. Mean survival time of frozen-thawed islet xenografts (39+/-3 days) was similar to that of noncryopreserved islet xenografts (43+/-6 days). This study demonstrates that cryogenic storage is feasible of isolated porcine islets, with the frozen-thawed pancreatic endocrine tissue maintaining morphological integrity and both in vitro and in vivo viability. Further studies are needed to define the effect of cryopreservation on the immunogenic properties of porcine islets