PubMed Health⌕ Search

Biomedical subjects

F Q Nuttall

Publications and source records attributed to F Q Nuttall.

At least 163 records · Page 9Linked to original sources

The effects of intensive glycemic control on neuropathy in the VA cooperative study on type II diabetes mellitus (VA CSDM).

To determine whether a difference in HbA(1c) could be safely sustained between a standard therapy (STD) arm and an intensive therapy (INT) arm, while maintaining HbA(1c) levels in both arms within a range acceptable in community practice. The effects of intensive treatment on various parameters were studied in this feasibility trial. We report here the results of 24 months of INT on peripheral and autonomic neuropathy.A prospective trial was conducted in five medical centers in 153 men of 60 +/- 6 years of age who had a known diagnosis of diabetes for 7.8 +/- 4 years. They were randomly assigned to a standard insulin treatment group (one morning injection per day) or to an intensive therapy group designed to attain near-normal glycemia and a clinically significant separation of glycohemoglobin from the standard arm. A four-step plan was used in the intensive therapy group along with daily self-monitoring of glucose: (1) an evening insulin injection, (2) the same injection adding daytime glipizide, (3) two injections of insulin alone, and (4) multiple daily injections. Peripheral neuropathy was diagnosed clinically by a history and physical examination, and by abnormal autonomic neuropathy Valsalva ratio (VR < 1.2) and RR variation (RRV < 10). An average HbA(1c) separation of 2.07% was achieved with INT, having HbA(1c) at or below 7.3% (p = 0. 001 versus STD). Baseline prevalence of peripheral neuropathy was 53% in STD, and 48% in INT. By 24 months, the prevalence increased to 69% in STD (p = 0.005 versus baseline), and to 64% in INT (p = 0. 008 versus baseline, but no different than STD). Though INT did not reverse all elements of peripheral neuropathy, there was a decreased prevalence of cranial neuropathy (p = 0.053 versus STD) and more frequent preservation of touch sensation in the upper extremities (p = 0.03 versus STD) in INT. At baseline, an abnormal Valsalva ratio and/or RR variation was seen in 38% of STD and 31% of INT. By 24 months in STD, the prevalence rose to 55% (p = 0.0067 versus baseline), and in INT, to 48% (p = 0.012 versus baseline and no different from STD). The prevalence of erectile dysfunction increased from 53% at baseline to 73% at 2 years, p = 0.002 in STD, and from 51% to 73% at 2 years (p = 0.003 versus baseline) and no different from STD. There was no change in the frequency of abnormal gastrointestinal or sweating symptoms. Our conclusion was that 2 years of meticulous glycemic control did not decrease overall prevalence of peripheral or autonomic neuropathy. In fact, the prevalence rose equivalently and significantly in both treatment arms. There was some benefit, however, in decreased frequency of cranial neuropathy and better preservation of touch sensation in INT.

Adult↗

In vivo phosphorylation of liver glycogen synthase. Effect of glucose and glucagon treatment of liver cells on the distribution of the [32P]phosphate.

Glycogen synthase was phosphorylated in vivo by perfusing rat liver or incubating liver cells with [32P]phosphate. It was then isolated by immunoprecipitation and subjected to exhaustive tryptic proteolysis. The trypsin-derived [32P]phosphopeptides were separated by high pressure liquid chromatography (HPLC). Incubation of in vivo phosphorylated synthase with endogenous synthase phosphatase to convert synthase D to synthase R resulted in removal of phosphate from all of the labeled phosphopeptides. In prelabeled liver cells treated with glucagon or glucose, the activities of synthase and phosphorylase changed in the direction expected. The total labeling in the immunoprecipitated synthase was found to be increased to 126% and decreased to 67% of the control with glucagon and glucose treatment, respectively. When the HPLC [32P]phosphopeptide profile of synthase from glucagon-treated animals was compared with that of controls, there were only minor differences in the two profiles. All the peaks were present and the proportion of labeling in each remained similar. There also was only a modest change in the [32P]phosphopeptide profile with glucose treatment when compared with that of controls. These results indicate that regulation of synthase activity in the hepatocyte involves changes in phosphorylation at multiple sites. Indeed, in 32P-labeled liver cells, all of the labeled sites appeared to be involved.

Animals↗

Insulin and glucose responses to various starch-containing foods in type II diabetic subjects.

The circulating insulin and glucose responses in type II diabetic subjects were determined for 5 h after ingestion of various meals, each containing 50 g carbohydrate. The purpose of the study was to 1) systematically study the insulin response to several different high-starch foods, 2) determine whether this insulin response could be predicted by the glucose response, and 3) determine whether the glucose response could be predicted by the physical structure and digestibility of the ingested carbohydrate. Each subject served as his own control. Carbohydrate was given in the form of potatoes, bread, oatmeal, rice, lentils, kidney beans, cornflakes, high-amylose corn muffins, and low-amylose corn muffins. Bread, oatmeal, rice, lentils, kidney beans, and high-amylose corn muffins resulted in a significantly lower glucose area than 50 g glucose, and the glucose response generally could be predicted by the physical structure and the known digestibility of the ingested carbohydrate. The insulin rise was statistically significantly greater than would be predicted from the glucose response for oatmeal, lentils, kidney beans, and high-amylose corn muffins. Although not statistically significant, the mean was greater than predicted for every other food except potatoes when the insulin response to 50 g glucose was used as a standard. These results indicate that the insulin response cannot be predicted by the glucose response.

Aged↗