bluuebunny/crossref_metadata_2025_split huggingface dataset:
In Vitro Metabolism of Glucose by Adipose Tissue from Rats Bearing a Growth Hormone Secreting Tumor (MtTW15)
Authors: Chattopadhyay D P , Akerblom H K , Martin J M 
Published: December 2014

Studies were made in rats bearing the growth hormone secreting tumor (MtTW15). There was (a) a generalized depletion of depot fat with a decrease of its total fatty acidcontent, and increased rate of lipolysis, (b) a rise in the fasting levels of serum FFA detectable only during theearly period of tumor development, and (c) a severe depression of the in vitro metabolism in adipose tissue of glucose to CO2 and fatty acids. The addition of insulin could not restore the lowered values to the basal level of the controls.
These findings indicate that chronically elevated levels of GH decrease the glucose utilization and insulin responsivenessof rat adipose tissue and suggest that rats bearing this particular tumor constitute a suitable experimental model for studies on the metabolic effect of hypersommatotropism
Effects of Oral and Intravenous Glucose Loading in Thyrotoxicosis: Studies of Plasma Glucose, Free Fatty Acid, Plasma Insulin and Blood Pyruvate Levels
Authors: Doar J W H , Stamp T C B , Wynn V , Path F C , Audhya T K 
Published: December 2014

Plasma glucose, NEFA, insulin and blood pyruvate levels before and after oral/intravenous glucose administration have been compared in a group of twenty-eight thyrotoxic subjects and a group of control subjects matched for age, sex and degree of obesity.
The mean fasting plasma glucose level was elevated, and 44 per cent of oral and 24 per cent of intravenous glucose tolerance tests were impaired in the thyrotoxic group.
The mean plasma insulin level in the thyrotoxic group was elevated both before and after oral and intravenous glucose administration.
Mean fasting plasma NEFA levels were elevated in the thyrotoxic group but fell to normal levels following glucose administration.
Mean fasting blood pyruvate levels were similar in control and thyrotoxic groups but abnormally elevated levels were observed in the latter following oral glucose administration.
Mean fasting serum triglyceride levels were similar in both groups, but the mean fasting serum cholesterol was significantly lower in the thyrotoxic subjects.
The possible significance of these abnormalities is discussed.
Levels of Plasma Insulin During Cortisone Glucose Tolerance Tests in “Nondiabetic” Relatives of Diabetic Patients: Implications of Diminished Insulin Secretory Reserve in Subclinical Diabetes
Authors: Rull Juan A , Conn J W , Floyd John C , Fajans Stefan S 
Published: December 2014

Plasma levels of insulin were determined during standard oral glucose tolerance tests and during cortisone glucose tolerance tests performed upon “nondiabetic” subjects (normal standard GTT) who were first degree relatives of diabetic patients. The standard test was also performed upon mildly diabetic patients and healthy control subjects. The results of the standard glucose tolerance test (levels of plasma insulin and blood glucose) did not differentiate the relatives with positive cortisone glucose tolerance tests (subclinical diabetes) from those with negative cortisone glucose tolerance tests although in both groups levels of plasma insulin were lower than in healthy subjects. However, the results of the cortisone glucose tolerance test did distinguish the group with subclinical diabetes from the relatives with negative tests since the secretion of insulin was delayed and insufficient in the subjects with positive testsl During the standard test patients with mild “maturityonset” diabetes showed delayed and insufficient secretion of insulin as compared to the healthy subjects.
It is concluded that during the cortisone glucose tolerance test, “nondiabetic” relatives of diabetic patients who have positive tests (subclinical diabetes) exhibit a defect in the secretion of insulin which distinguishes them from subjects with negative tests. This defect is similar in pattern to that observed in mildly diabetic patients during the standard test. This deficiency in the secretion of insulin represents an important part of the mechanism which induces a positive cortisone glucose tolerance test.
This demonstration that, in some relatives of diabetics, a grossly normal standard glucose tolerance can exist at a time when decreased reserve insulin secretory capacity can be measured, justifies a careful evaluation of whether some form of therapy is indicated at this stage of the disease (subclinical diabetes) and, if so, what form it should be. The meaning of the statistically significant subnormal response of plasma insulin to a standard glucose load in relatives with negative cortisone glucose tests is not yet apparent. Since in them the reserve insulin secretory capacity, as measured by the CGTT, remains intact, it is premature, pending additional data, to raise the question of possible treatment of this group.
Transplantation of a Pancreatic Insulinoma into an Insulin-resistant Patient with Juvenile Diabetes
Authors: Urea I , Kott I , Lev-Ran A 
Published: December 2014

A case of juvenile diabetes who developed insulin resistance is presented. Despite insulin requirements of 300 U. a day his diabetes, of one-year duration, was inadequately controlled. On March 17, 1968 transplantation of a pancreatic insulinoma was performed. The tumor was excised from a fifty-three-year-old female patient suffering from hypoglycemic attacks and inserted beneath the fascia lata of the young patient. One week after the transplantation he was aglycosuric. Biopsy of the transplant three months later as well as biologic assess showed viable pancreatic tissue. Ten months after transplantation there was no biologic activity of the transplant; histology showed complete disappearance of pancreatic stroma with fibrous and cellular infiltration.
Despite these findings the patient feels well, works fully in the rural settlement and is controlled with 125 U. of Iletin (highly concentrated bovine insulin, 500 U. per 1 ml.) in one morning injection. It is not certain if the patient's improvement was due to the insulinoma or was coincidental.
Studies of Insulin Secretion in the Perfused Rat Pancreas: Effect of Diazoxide and A025
Authors: Basabe Juan , Lopez Nestor , Viktora Josef , Wolff Frederick 
Published: December 2014

Continuous glucose stimulation produces two phases of insulin secretion in the isolated perfused rat pancreas. Puromycin has no effect on the first phase but partially inhibits the second. The second phase has been reported previously to be associated in part with insulin synthesis.
In acute experiments, diazoxide and its derivative—A025—inhibit insulin secretion in both phases. This inhibition corresponds with an increase of the pancreatic tissue insulin content. These results suggest that both A025 and diazoxide decrease insulin release but have no effect on its synthesis.
In pancreatic perfusion of rats which had been chronically treated with diazoxide and A025 (per os), and who had been fasted and without drug for sixteen hours before the experiment, a greater insulin secretion was demonstrated in both phases compared with normal controls; however, if the perfusion is done three to four hours after the last dose, the amount of insulin secreted is smaller than the respective controls. This again suggests that during the period of action of the drug, pancreatic insulin is not released, but synthesis is not inhibited. The result, therefore, is an accumulation of insulin within the beta cells.
The acute and chronic experiments done under our experimental conditions in the perfused rat pancreas suggest that diazoxide and A025 inhibit insulin release, but have no effect on insulinogenesis.
Immunological Studies of the A and B Chains of Insulin
Authors: Touber Jan L , Stoll Ralph W , Ensinck John W , Williams Robert H 
Published: December 2014

Radioimmunoassays for the measurement of the A and B chains of insulin were developed using antisera against S-sulfonated, oxidized and reduced derivatives of the chains. Antisera against S-sulfonated A chain were found to react with S-sulfonated A chain, but not with the oxidized or reduced A chain whereas antisera against the reduced or oxidized A chains reacted with all three (S-sulfonated, oxidized and reduced) A chain derivatives. Antisera against all three B chain derivatives reacted equally well with B chain preparations whether S-sulfonated, oxidized or reduced. Because of greater stability radioiodinated oxidized chain -preparations were employed in the assay rather than radioiodinated S-sulfonated chains.
Although the A and B chain immunoassays were specific for one or more antigenic sites on the A and B chain respectively, they were not specific for the chains alone since insulin, proinsulin, and convertible and nonconvertible fractions of proinsulin cross-reacted in both assays, especially in the B chain assay.
Plasma interfered in both assays in a nonspecific and nonuniform fashion. With this consideration, no evidence has been found that the chains of insulin were present in the: (1) plasma of fasted man, baboon and pig, (2) plasma of man and pig after oral glucose, (3) plasma of baboon and pig after intravenous insulin, or (4) perfusate of isolated rat liver after insulin administration.
Ultrastructural Changes in B Cells of Pancreatic Islets from Rats with Elevated Levels of Circulating Growth Hormone Secreted by MtT-W15 Tumor
Authors: Bencosme Sergio A , Tsutsumi Victor , Martin Julio M , Åkerblom Hans K 
Published: December 2014

The pancreatic B cells from rats bearing a growth hormone-producing tumor (MtT-W15) were studied by electron microscopy before and after incubation in media containing alternatively low (60 mg./100 ml.) and high (300 mg./ 100 ml.) glucose concentrations.
Tumor-bearing rats had been previously shown to have increased blood levels of somatotrophin and insulin and also to have B cells with increased responsiveness to in vitro glucose stimulation.
B cells from tumor-bearing rats, when compared with controls, showed (1) an increased number of secretory granules, (2) a marked increase in the proportion of pale to dark granules (30 to 60 per cent, as compared with 5 to 25 per cent for controls), and (3) the presence of numerous dilated cisternae of rough endoplasmic reticulum containing a flocculent material resembling the core of the pale granules. The last observation may indicate that pale secretory granules are formed in the endoplasmic reticulum of these hyperactive B cells. The fact that the hyperfunctioning B cells present in tumor-bearing rats possess a high number of pale granules suggests that these granules participate in the processes of insulin synthesis, storage, and secretion.
Pancreatic islets from control and tumor-bearing rats alternatively incubated in media with low and high glucose concentrations did not reveal significant morphological changes when compared with the nonincubated islets from the same animals. The extent of degeneration and necrosis observed in some B cells from control and tumor-bearing animals after incubation were unrelated to the glucose concentration in the incubation media.
Insulin Biosynthesis in Experimental Hereditary Diabetes
Authors: Poffenbarger Phillip L , Chick William L , Lavine Robert L , Soeldner J Stuart , Flewelling Judith H 
Published: December 2014

Studies of proinsulin-insulin relationships were performed on serum and isolated pancreatic islets from normal (C57 BL/Ks) and spontaneously diabetic (CSlBL/Ks-dbdb) mice. The diabetic syndrome in these animals is inherited as an autO8omal recessive trait with complete penetrance and is characterized by the early development of obesity and hyperinsulinemia, followed by progressive hyperglycemia.
Gel nitration chromatography of diabetic mouse serum revealed that proinsulin comprised a relatively small proportion (9.6 per cent) of the total circulating insulin immunoreactivity.
Although diabetic mouse islets were enlarged, insulin content per islet was diminished, while proinsulin content per islet was similar to normal. Islet proinsulin:insulin ratios correlated sgnificantly with both blood glucose and serum insulin levels. This appeared to result from the fact that sustained hyperglycemia caused mainly a depletion of islet insulin, whereas proinsulin content remained unchanged, thereby increasing proinsulin:insulin ratios.
In vitro labeling experiments with H-3-leucine demonstrated no significant difference in the rate or pattern of incorporation of radioactivity into proinsulin and insulin fractions of normal and diabetic islets after 90 and 180 minutes of incubation.
Therefore, the apparent biological ineffectiveness of the high circulating levels of immunoreactive insulin in this diabetic syndrome did not appear to be the result of a disproportionate release of biologically less potent proinsulin, nor did there appear to be a detectable abnormality in proinsulin-insulin biosynthesis as assessed by these methods.
Carbohydrate-induced Hypertriglyceridemia: Inhibition by Phenformin
Authors: Owen W Crawford , Kreisberg Robert A , Siegal Alan M 
Published: December 2014

The effect of phenformin on the induction of plasma triglyceride by high-carbohydrate feeding was studied in ten subjects (nine normals and one Type II, hyperlipoproteinemia). Each study was divided into four periods. During periods I and III, each subject received an American Diabetes Association diet calculated to maintain body weight and in periods II and IV a high-carbohydrate diet (85 per cent of the calories derived from carbohydrate) which was isocaloric with the control diet. Phenformin, 50 mg. twice daily, was administered in either period II or IV in association with the high-carbohydrate diet. There was no change in weight during the study. The plasma triglyceride increase (ΔTG) during the high-carbohydrate diet alone was 103 mg. per cent as compared with a ΔTG of 26 mg. per cent during the high carbohydrate-phenformin period, a highly significant difference (p &lt; 0.005).
Insulin secretion and glucose tolerance during each period was determined by the sum of the increments above base baseline of plasma insulin and glucose concentrations during a five-hour oral glucose tolerance test. No significant differences in glucose tolerance or in insulin secretion occurred during any of the periods despite the alterations produced by the high-carbohydrate diet and phenformin in plasma triglyceride concentrations. A slight correlation could be demonstrated between the insulin response to a glucose load while on the control diet and the magnitude of the triglyceride response on the high-carbohydrate diet. The data indicate that (1) phenformin inhibits the induction of plasma triglyceride produced by carbohydrate loading, (2) there was no correlation between the changes in plasma triglyceride concentrations, glucose tolerance or insulin responsiveness during the experimental periods and (3) the magnitude of the increase in plasma triglyceride concentration may be related to the insulin response to a glucose load during the control period.
Diabetic Retinopathy: New Vessels Arising from the Optic Disc: II. Response to Pituitary Ablation by Yttrium 90 Implant
Authors: Panisset A , Kohner E M , Cheng H , Fraser T R 
Published: December 2014

The response of new vessels arising from the optic disc to pituitary ablation was studied in sixty-six eyes of forty-five patients over six months to four years. The response was related to the extent of pituitary ablation graded as complete, intermediate or slight from endocrine tests done three months post-implant.
Following complete ablation there was a significant improvement in new vessels. A similar trend (but not significant values) was observed in partially ablated patients, while those with slight ablation showed no change.
Retinitis proliferans deteriorated in all groups, but least in those with complete and most in those with slight ablation. The mean visual acuity in the completely ablated group did not change, while it deteriorated significantly in the slight ablation category.
Patients under forty years of age at the time of the operation benefited more than those over forty.
It is concluded that new vessels on the disc respond to complete and intermediate pituitary ablation, complete ablation being superior in its effectiveness.
Response to Intravenous Glucose in Juvenile Macaque Monkeys: Effect of Central Nervous System Lesions and Species Difference
Authors: Cornblath Marvin , Levitsky Lynne L , Kling Arthur 
Published: December 2014

The influence of central nervous system lesions as well as species difference upon the response to a 0.5 gm./kg. intravenous glucose load has been evaluated in two primate species. The glucose, insulin, free fatty acids (FFA) and growth hormone response of four control M. mulatta did not differ significantly from that of three monkeys sustaining lesions of the amygdaloid nuclei or four animals with cortical lesions. However, glucose levels were lower and FFA levels higher in eight studies in six M. speciosa following cortical lesions compared to six control M. speciosa. The glucose disappearance rate (Kt) was significantly higher in the operated M. speciosa.
After intravenous glucose administration, the M. speciosa group had a significantly lower glucose response and a higher insulin response than did the M. mulatta. Free fatty acid levels were lower in control M. speciosa compared to M. mulatta, but higher in operated M. speciosa. Reserpinization or acclimatization to a primate chair did not alter the glucose and insulin response of M. mulatta.
Glucose Production from Fructose
Authors: Atwell Marshall E , Waterhouse Christine 
Published: December 2014

Five adult subjects, three male and two female, were given fructose-U-C-14 by single injection under the condition of fructose loading. The radioactivity in glucose was determined in serial arterial samples. On a separate day, glucose-6-C-14 was given to these same subjects under identical conditions. Using these two curves, the fructose converted to glucose was determined. In these subjects an average of 30.94 per cent of the infused fructose appeared as blood glucose.
Hepatic vein catheterization showed a large positive arteriovenous difference for fructose (50 to 80 per cent of infused fructose) and negative arteriovenous differences for glucose and lactate. There was a discrepancy between the calculated fructose conversion to glucose (30 per cent) from the tracer studies and the glucose production estimated from the hepatic arteriovenous differences of glucose (10 per cent). Supporting data for the validity of the former figure are given.
The simultaneous hepatic production of glucose and lactate by the liver is most likely due to the large substrate load of fructose entering the glycolytic scheme at a point which bypasses the rate limiting enzymes for both glycolysis and gluconeogenesis.
Sensitivity and Specificity of Five Screening Tests for Diabetes in Ten Countries
Authors: West Kelly M , Kalbfleisch John M 
Published: December 2014

The sensitivity and specificity of each of five screening tests were estimated in each of three to ten countries by testing subjects drawn from the general populations of adults over thirty-four years of age. This permitted comparisons among countries and among the different tests (fasting, postprandial, and postglucose urine tests, and fasting and postprandial blood glucose values).
Sensitivity and specificity of each test varied widely among populations. For example, the sensitivity of the twohour urine glucose ranged from 17 per cent in Nicaragua to 100 per cent in East Pakistan. Apparently specificity and sensitivity of such tests are influenced by many factors including both the circumstances under which the tests are performed and the characteristics of the population tested. It is, therefore, not possible to predict prevalence rates reliably by extrapolating from the results of screening tests. However, we believe the data for specific populations on the sensitivity and specificity of various tests will provide a rough guide in predicting the cost-effectiveness of alternative approaches to case detection in those particular countries. For instance, these results suggest that roughly 56 per cent of the occult diabetics in Costa Rica in this age group would be detected by a two-hour urine glucose, but only about 41 per cent of those in whom this test was positive would prove to have diabetes.
Even modest changes of criteria in defining either “diabetes” or Department of Medicine, University of Oklahoma School of Medicine, Oklahoma City, Oklahoma 73104.“abnormality” of the screening results produced marked changes in rates of sensitivity and specificity. With few exceptions, tests which were more sensitive were, comparably, less specific, and the reverse was also true. Rates of “diabetes” were markedly influenced by modest changes in diagnostic criteria.
Quantitative Measurements of Skin Capillary Resistance in Hypophysectomized Long-term Diabetics
Authors: Christensen Niels Juel , Terkildsen Anne Birgitte 
Published: December 2014

Quantitative measurements of skin capillary resistance were carried out in twelve control subjects, eight long-term diabetics with proliferative retinopathy, and in sixteen diabetics hypophysectomized for diabetic retinopathy. Ten individual measurements of capillary resistance were performed on each subject. All subjects but two were less than fifty years of age.
In the control subjects, the mean capillary resistance ranged from 144 to 222 mm. Hg. With the exception of two, all had mean values between 150 and 200 mm. Hg.
The long-term, nonoperated patients demonstrated fragile capillaries. All but one of these patients had mean values below 150 mm. Hg (range 90 to 160 mm. Hg). Most of the hypophysectomized diabetics had a mean capillary resistance above 200 mm. Hg (range 162 to 372 mm. Hg). The values were significantly increased in comparison with the results obtained in the control subjects and in the nonoperated diabetics.
Reactive Hypoglycemia in Women: Results of a Health Survey
Authors: Jung Y , Khurana R C , Corredor D G , Hastillo A , Lain R F , Patrick D , Turkeltaub P , Danowski T S 
Published: December 2014

1. Reactive hypoglycemia (for the purpose of this evaluation: blood glucose levels of 59 mg. per 100 ml. or less at the second, third, fourth or fifth hours of an oral glucose tolerance test) occurred in about 17 per cent of a group of 285 adult females participating in a survey.
2. This degree of reactive hypoglycemia occurred more often in the younger members (twenty to forty-five years of age), i.e., in 19 per cent of those with body weight less than 146 lbs. and in 31 per cent of those whose weight was above this range. Hypoglycemia was distinctly less frequent in the older nonoverweight females (2 per cent) and in the older obese group (11 per cent).
3. The lesser frequency of this degree of reactive hypoglycemia in the older nonobese and obese groups is attributable to higher fasting levels of glucose and to greater increments in blood glucose levels following upon an oral glucose load and not to any decrease in the usual increments in insulin.
4. In the two younger groups (twenty to forty-five years of age and either less than 146 lbs. or 146 lbs. or more in weight), those with reactive hypoglycemia as defined above had lower fasting blood glucose levels. This fact alone accounted for the subsequent occurrence of hypoglycemia. This conclusion is supported by the finding that the responses of those with and those without the stated degree of hypoglycemiaare Indistinguishable in terms of increments in blood glueose increments in insulin, and in the rations of the two.
5. Our data permit the generalization that blood glucose levels between 59 and 41 mg. per 100 ml. in the later hours of an oral glucose tolerance test are so common in young individuals, nonobese and obese, that this must be taken into account in any evaluation of so-called functional or reactive hypoglycemia in persons of this age. This degree of hypoglycemia is much less frequent in persons above forty-five of age.