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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aims of this study were to determine whether diabetes could be ameliorated in dogs by autotransplantation of pancreatic fragments to the spleen and to determine the optimal time of collagenase digestion for pancreatic tissue dispersal. Forty-eight dogs were made diabetic by total pancreatectomy. Fifteen dogs not further treated survived 7.0+/-1.1 (SE) days with a mean plasma glucose of 401+/-5 (SE) mg/100 ml 2 days after pancreatectomy. The pancreases of 33 dogs were distended with Hanks' solution, minced, digested with collagenase (600 microns/ml of tissue), for 0 to 25 minutes, and autotransplanted to the splenic pulp. The incidence of permanent normoglycemia (fasting plasma glucose less than 150 mg/100 ml) and the K value of glucose tolerance tests (GTT) performed 2 and 10 weeks after transplant were determined in experimental groups divided according to the length of collagenase digestion. All five dogs receiving undigested tissue remained hyperglycemic. One of seven dogs receiving tissue digested for 10 minutes became normoglycemic. In contrast, seven of eight, seven of seven, and six of six dogs receiving tissue digested for 15, 20, and 25 minutes, respectively, became normoglycemic (followed for 6 months). K values at 2 weeks were 1.20+/-1.19 (SE)% 1.60+/-0.25 (SE)%, and 0.78+/-0.08 (SE)% in the normolgycemic dogs of the 15, 20, and 25 minute digestion groups, respectively. The K value of normal dogs was 3.30+/-0.27 (SE)%. The glucose tolerance curves of the 20 minute group at 2 and 10 weeks most nearly approximated the curves of normal dogs. K values improved in all recipient dogs. Diabetes recurred immediately and death occurred at a mean of 4.8+/-1.5 days in 12 recipient dogs following splenectomy. We conclude that pancreatic fragments can be successfully autotransplanted to the spleen without separation of endocrine and exocrine tissue and that 20 minutes is the optimal period of collagenase digestion for tissue preparation.
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PMID:Autotransplantation of pancreatic islets without separation of exocrine and endocrine tissue in totally pancreatectomized dogs. 19 58

Gingiva from alloxan and streptozotocin-diabetic rats exhibited markedly enhanced collagenolytic activity in tissue culture. This effect was eliminated by puromycin or by repeated freeze-thawing of the tissue prior to incubation. Soluble extracts of the diabetic gingiva in situ were found to contain breakdown products of collagen similar in size to the reaction products generated by tissue collagenase. These fragments were not detected in the control tissue. This study indicates that experimental diabetes stimulates the synthesis of gingival collagenase in culture and that a similar effect occurs in vivo.
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PMID:Enhanced collagenase activity in diabetic rat gingiva: in vitro and in vivo evidence. 21 Feb

The metabolic response to repeated isologous transplantation of isolated pancreatic islets was studied in 11 streptozotocin-diabetic AGUS rats. The islets were isolated with collagenase and transplanted intra-portally in batches previously found to be quantitatively insufficient for reversal of the diabetic state. Primary transplantation caused a slight improvement whereas retransplantation with the same number of islets three weeks later was followed by normalization of blood glucose, plasma insulin, urine volume and urine glucose per 24 hours during a three-month observation period. Repeated isologous transplantation of isolated pancreatic islets has an additive effect on the metabolism in that two insufficient tissue doses correct streptozotocin induced diabetes in the rats.
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PMID:Repeated isologous transplantation of islets of Langerhans in the diabetic rat. 21 67

The influence of histocompatibility on islet transplantation in dogs was studied. Donors and hosts were chosen by help of the macrophage-electrophoresis-mobility test. By subtotal pancreatectomy and twice applying streptocotocin diabetes was successfully induced in recipient animals. Isolation of pancreating islets from the donor was done by means of the collagenase method combined with the Ficoll-gradient-separating technique. The grafting occurred via portal vein into the liver. Significant decrease of blood sugar during 10 weeks was observed in animals with good compatibility. This effect lasted only 14 days in cases of bad compatibility. Concentrations of insulin in the portal vein and superior caval vein 4 weeks after grafting was lower in cases with high-grade histoincompatibility. The duration of functioning of transplanted islets depends on the histocompatibility.
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PMID:[Results of islet transplantation in diabetic dogs]. 21 71

There are conflicting data in the literature regarding the role of monamines in the secretion of insulin. In order to clarify the contribution that species variation may make to these divergent results, the uptake of serotinin (5-HT), dopamine (DA), and their precursor amino acids, 5-hydroxytryptophan (5-HTP) and L-dopa, into islets was studied. Islets from golden hamsters, rabbits, guinea pigs, and obese, hyperglycemic mice were isolated by the collagenase technique. The islets were incubated in Krebs-Ringer buffer in the presence of 14C-labeled monamines or their precursors. At 30-minute intervals after initiating the study, the incubation mixture was passed through a Millipore filter. The retained islets were disrupted by sonication and the radioactivity counted. The ratio of the uptake of 5-HTP to 5-HT was at least 3:1 in the hamster, guinea pig, and mouse. In the rabbit the ratio was 1:1. A similar relationship was noted for the uptake of L-dopa and DA. The in-vitro results were confirmed by the in-vivo studies, in which hamsters were injected with 14C5-HT or 5-HTP, followed by isolation of the islets. We conclude that there is significant species variation inthe uptake of these monoamines and their precursors.
Diabetes 1977 Apr
PMID:Species variation in pancreatic islet monoamine uptake and action. 32 Dec 87

In the present work, homogeneous isolated pancreatic islet-cells were transplanted to diabetic rats with the aim of verifying if the transplanted tissue could survive and reduce the plasma glucose concentration on the alloxan-induced diabetic receptors. For the isolation of the pancreatic islets, pancreas was incubated in collagenase solution for about 13 +/- 3 minutes, followed by centrifugation in Ficoll gradients. The islets, 3 000 to 5 000, were transplanted to alloxan diabetic recipients, in a territory, preferentially with portal-hepatic drainage (mesentery and spleen). Sixty per cent of the recipients exhibited a fall of the plasma glucose concentration, up to 70%, while in the control animals, the diabetes persisted. The islets were found in the recipients mesentery up to 10 days after transplantation, and all of them showed heavily granulated (aldehyde fuchsin positive) beta cells. After this time, islets were not found. These results indicate that islets can survive and attenuate diabetes in alloxan-treated rats, and that, probably, the number of islets transplanted as well as the receiving areas play an important role.
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PMID:Transplantation of islets of Langerhans in diabetic rats. 35 20

Six normal weight subjects without any heredity of diabetes (group 1), 3 obese subjects with normal (group 2) and 9 with pathological carbohydrate tolerance (group 3) were characterized by a 2-h glucose infusion test. Adipose tissue fragments were obtained from the abdominal wall by surgical biopsy under intracutaneous anesthesia. Adipocytes were isolated by collagenase digestion and incubated in buffer containing [1-14C] glucose and different concentrations of insulin. The metabolic effect of insulin was expressed as percent increase above control 14CO2 production. Maximal CO2 raised to 207 +/- 25% and 154 +/- 9% in groups 1 and 2, respectively. These values were significantly higher than in obese subjects displaying a pathological carbohydrate tolerance (group 3; 119 +/- 6%). A negative correlation was found between blood glucose levels and biological activity of insulin on adipocytes. The results suggest that insulin sensitivity of target tissue seems to play an important role in development of carbohydrate intolerance.
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PMID:Relationship between carbohydrate tolerance, insulin secretion, and insulin sensitivity of isolated fat cells from obese protodiabetics. 36 Jul 50

Transplantation of isolated islets of Langerhans has been suggested as a treatment of certain forms of diabetes mellitus. Injection of 200-400 syngeneic pancreatic islets isolated by collagenase digestion into the pancreas or submandibular gland of diabetic rats rendered most of the hosts nearly normoglycaemic. Blood glucose determinations were monitored for 2 months after islet transplantation. Although intrapancreatic and intrasubmandibular implantation reduced hyperglycaemia and polyuria in these animals, consistent normal values were rarely achieved.
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PMID:Experimental pancreatic islet transplantation. 40 49

Pancreatic islets from adult donors were transplanted intraportally into 32 inbred, adult AGUS rats with streptozotocin diabetes. The islets were isolated with collagenase and counted individually. A relationship between the number of islets transplanted and the metabolic response could be demonstrated. Transplantation of less than 200 islets did not change the diabetic state. Rats receiving 200-220 improved, while recipients of 240-800 islets all exhibited normal values of blood glucose, plasma insulin, urine volume and urine glucose. The glucose tolerance, however, remained abnormal in all animals.
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PMID:Metabolic response to isologous transplantation of small numbers of isolated islets of Langerhans in the rat. 41 21

The influence of warm ischemia on pancreatic islet viability was studied by means of 63 isologous transplantations in adult AGUS rats. The pancreases were harvested 0, 20 and 40 min after circulatory arrest. The islets were isolated with collagenase and transplanted intra-portally in known numbers into streptozotocin-diabetic recipients. The islet-dose-metabolic-response relationships in three groups of recipients were compared. No significant difference was found in the quantitative yield. The smallest number of islets which reversed diabetes increased by 25% after a period of warm ischemia regardless of its duration.
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PMID:Viability of the islets of Langerhans after warm ischemia as judged by isologous transplantation. 41 67


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