PubMed Health⌕ Search

Biomedical subjects

Q Carta

Publications and source records attributed to Q Carta.

At least 37 records · Page 2Linked to original sources

Insulin binding to isolated monocytes and adipocytes in the study of hypoglycemic subjects and in the follow-up of patients with insulinoma.

The present study was performed to see whether insulin receptor evaluation is useful as a diagnostic tool in the differential diagnosis of hypoglycemia. The receptor numbers and affinity constants of insulin binding to adipocytes isolated from subcutaneous tissue were determined in 5 metabolically healthy subjects, undergoing laparatomy for cholecystectomy, and in 4 patients undergoing surgery for insulinoma removal. The specific insulin binding to monocytes at physiological concentrations (1 ng/ml) was also determined in all these subjects, and in 6 patients with functional hypoglycemia. The study was repeated in insulinoma patients 7 days after surgery. Results show that insulinoma patients before tumor removal have greater than 50% fall in binding capacity on both monocytes and fat cells, in keeping with the down-regulation mechanism, whereas the values for patients with functional hypoglycemia are in the normal range. After surgery, the insulin binding to monocytes sharply increased, nearly to the lower level of the normal range when the insulinoma was removed; no change was observed when the tumor was not resected (case 3). Insulin receptor study may therefore be of diagnostic and prognostic assistance in the investigation of hypoglycemic syndromes.

Adenoma, Islet Cell↗

Hemofiltration in diabetic uremic patients.

The increasing number of Diabetic Uremic Patients (DUP) starting the substitutive treatment (ST) constitutes a difficult and often disappointing problem in terms of efforts, clinical results and side-effects. While treatment of these patients by C.A.P.D. is well documented, the adoption of Hemofiltration (HF), has been, up to now scarcely considered. In order to define the potentialities of a HF policy in the treatment of these patients, data from 6 DUP treated with postdilutional HF for a 10.6 months/patient period were collected on a multi-center basis and retrospectively examined. Good results were achieved in terms of vascular stability, control of arterial hypertension and of retinopathy, clinical complications and hospitalization rate. Although C.A.P.D. may represent a first choice treatment for DUP with residual function, satisfactory glicemic control, difficult blood access and a motivation to full autonomization, HF may constitute a logical alternative when C.A.P.D. should be unmanageable (visus impairment, history of repeated peritonitis and dismetabolism, considerable weight gain): an integration of HF and C.A.P.D. can assure PDU with a continuative treatment.

Blood↗

The risk of pronounced hyperkalaemia after arginine infusion in the diabetic subject.

Following previous work showing that i.v. arginine induces a fall in blood phosphorus and an increase in blood potassium in normal subjects, investigation of the mechanism underlying these metabolic changes was extended to a group of 14 insulin-dependent diabetics and a further 6 normal volunteers. In the diabetics, arginine (0.5 g/kg body weight) in 30 min caused a slight, but significant fall in blood phosphorus (delta = -0.40 +/- 0.04 mg/ml p less than 0.01). This was well below the fall noted in the normal subjects, which, as demonstrated in the earlier study, is to a great extent mediated by insulin. The increase in blood potassium was much more marked than in the normal subjects (delta = + 1.42 +/- 0.15 mEq /l; p less than 0.001) and rose to pathological levels (5.6 to 6.5. mEg/l) in 9 out of 14 patients. There were no significant changes in blood pH, plasma osmolality, or plasma aldosterone. Inhibition of the glucagon response to arginine by means of a priming dose of 250 micrograms somatostatin, followed by infusion of 1,500 micrograms/hr, did not abolish the rise in blood potassium. These findings indicate that insulin protect against arginine-induced hyperkalaemia and that this metabolic alteration does not depend on glucagon, acidosis, enhance plasma osmolality, nor the suppression of aldosterone secretion. Persons with low insulin secretion due, for example, to stress or diabetes, run the risk of pathological hyperkalaemia if subjected to i.v. infusion of arginine.

Adolescent↗

[Value of the method of Cerasi and Luft in checking the progression of metabolic disorders in childhood].

The method of Cerasi & Luft was evaluated after 6 months and 1 yr of dietary management in 7 children with familial diabetes and/or very slight clinical and laboratory symptoms, and one obese girl. There was a marked reduction in the blood insulin area in the obese subject, whereas the remainder of the series displayed stationary pictures. It is felt that the method deserves emphasis on account of its constant evocation of a reproducible response and the possibilities of interpretation that it offers in the field of paediatrics.

Blood Glucose↗

To what extent does the artificial pancreas facilitate the surgery of preoperatively not localized insulinomas?

The patient study has been performed in order to evaluate the usefulness of the artificial pancreas in the surgical management of previously not localized insulinomas. In the 4 patients studied, blood glucose was maintained both overnight and during surgery up to a preselected individualized level in order to avoid hypoglycemia. During surgery, only one patient required dextrose infusion. The continuous intrasurgical monitoring of blood glucose in the 4 cases examined showed that: (1) anesthesia induction, surgical incision and viscera mobilization were accompanied by a rise in blood glucose (10.30 mg/dl), reaching the highest levels 30-40 min after the start of the operation; (2) adenoma manipulation was followed by a drop in blood glucose (10.40 mg/dl), reaching the lowest level after 30-40 min; (3) adenoma resection was followed by a rise in blood glucose (25-40 mg/dl), particularly evident after 30-40 min. It is concluded that the artificial pancreas is certainly useful during surgery of insulin-producing tumors, allowing continuous monitoring of glycemia and avoiding dangerous blood glucose excursions: however, when the insulinoma is not identified during surgery, the periods elapsing between the surgical phases and the blood glucose changes observed can be too prolonged to ensure successful conservative serial pancreatectomy in all cases.

Adenoma↗