Improved control of type 2 diabetes mellitus: a practical education/behavior modification program in a primary care clinic.

BACKGROUND: This study was done to determine the efficacy and ease of administration of education/behavior modification classes, provided by a nurse and a dietitian in a primary care clinic for improving control of type 2 diabetes mellitus. METHODS: Patients were divided randomly into two groups. Eighteen patients completed 6 months of structured, office-based classes, and 20 similar patients served as control subjects. All were patients of the same group practice and had their usual office visits. Glycemic control, lipid levels, body weight, knowledge about diabetes, medication requirements, and symptoms were monitored during the 6 months, with follow-up at 12 months. RESULTS: At the end of 6 months, the intervention group had significant reductions in mean fasting blood glucose, glycosylated hemoglobin, total cholesterol, and low-density lipoprotein cholesterol (LDL-C) values. Their mean body weight was significantly reduced at 12 months, and their knowledge of diabetes was improved. Control patients had significant improvement only in glycosylated hemoglobin and body weight at 6 months. Minimal physician time was required. CONCLUSION: The education/behavior modification program was clinically worthwhile, and it was easy to administer.

AIDS-associated cryptosporidiosis with gastric stricture and a therapeutic response to paromomycin.

AIDS-associated cryptosporidiosis has been associated with severe, watery diarrhea and with multifocal biliary stricture. Gastric involvement has not been reported prominently. We report here the case of a 28-yr-old AIDS patient who developed typical watery diarrhea, followed by subtotal gastric obstruction secondary to antral stricturing. Biopsy of the stricture revealed severe inflammation and marked cryptosporidial infestation. Extensive workup excluded causes of stricture. He was empirically treated with paromomycin, with a surprisingly positive therapeutic response and clinical resolution of obstruction. Antral stricture may be another manifestation of cryptosporidial infection in AIDS. Paromomycin deserves further evaluation as an agent for treatment of this infection.

Palmitic and erucic acid metabolism in isolated perfused hearts from weanling pigs.

Hearts from 4 week-old weanling pigs were capable of continuous work output when perfused with Krebs-Henseleit buffer containing 11 mM glucose. Perfused hearts metabolized either glucose or fatty acids, but optimum work output was achieved by a combination of glucose plus physiological concentrations (0.1 mM) of either palmitate or erucate. Higher concentrations of free fatty acids increased their rate of oxidation but also resulted in a large accumulation of neutral lipids in the myocardium, as well as a tendency to increased acetylation and acylation of coenzyme A and carnitine. When hearts were perfused with 1 mM fatty acids, the work output declined below control values. Erucic acid is known to be poorly oxidized by isolated rat heart mitochondria and, to a lesser degree, by perfused rat hearts. In addition, it has been reported that erucic acid acts as an uncoupler of oxidative phosphorylation. In isolated perfused pig hearts used in the present study, erucic acid oxidation rates were as high as palmitate oxidation rates. When energy coupling was measured by 31P-NMR, the steady-state levels of ATP and phosphocreatine during erucic acid perfusion did not change noticeably from those during glucose perfusion. It was concluded that the severe decrease in oxidation rates and ATP production resulting from the exposure of isolated pig and heart mitochondria to erucic acid are not replicated in the intact pig heart.

31P NMR studies of the metabolic status of pig hearts preserved for transplantation.

31P NMR spectroscopy has been used to evaluate the metabolic status of cardioplegically arrested pig hearts. Hearts were stored with Plegisol for up to 12 hours at either 5 degrees C or 12 degrees C. Results indicated that the ATP content of hearts could be maintained (greater than 70% of initial values) for up to 5 hours in the ischemic storage state. The ATP loss was greater at 12 degrees C. PCr was lost exponentially under the same conditions. Functional testing by reperfusing the stored hearts in vitro indicated a good correlation between the ATP content and survivability of the preparations. Twenty-four hour preservation of pig hearts using slow perfusion with a modified cardioplegic solution (Wicomb) allowed for preservation of both PCr and ATP, in all cases, reperfusion of hearts revealed a loss of NMR- visible ATP and PCr.

Effect of therapeutic level ultrasound on visual evoked potentials in the hypoxic cat.

The effect of 1.0 MHz ultrasound at an intensity of 1.0 W/cm2 SATA on brain function of anaesthetized cats was assessed using Visual Evoked Potentials (VEPs). Ultrasound alone did not significantly modify the averaged VEP signals. However, acute hypoxia depressed the VEP response. When the brain was exposed to ultrasound during the hypoxic episode, the VEP response remained normal. Raising brain temperature by whole body heating could not mimic the beneficial effect of ultrasound on the VEP response during hypoxia. This suggests that therapeutic ultrasound may have a protective effect on hypoxic tissues and may have clinical applications.

A simple fiber optic monitor of cardiac and respiratory activity for biomedical magnetic resonance applications.

A fiber optic reflectometer, capable of monitoring physiological parameters in a high magnetic field without significant disturbance of either rf or static fields, is described. Both cardiac and respiration rates were monitored with this optical device while 31P NMR spectra of the liver of an anesthetized rat were acquired.

Ultrasound intensity and contractile characteristics of rat isolated papillary muscle.

The effect of graded intensities of continuous wave ultrasound on the contractile performance of isolated papillary muscle of rat was tested. Under isometric conditions rat left ventricular papillary muscles (n = 48) were electrically stimulated to contract at rates of 30, 60, 120 and 240 beats per minute. Muscles were perfused with a Tyrode solution at 30 degrees C under normoxic conditions. Ultrasound at intensities of 0.25, 0.50, 1.0 and 2.0 W/cm2 spatial average temporal average (SATA) at 963 kHz was applied to the muscles while recording muscle contractile characteristics. The analog data were digitized and stored on disk for analysis by computer. This revealed a significant (p less than 0.001) increase in peak developed force (F), peak rate of force development (+dF/dt) and peak rate of myocardial relaxation (-dF/dt) that was linearly related to ultrasound intensity. The muscles were more sensitive to ultrasound at 240 contractions per minute. Resting force was significantly decreased by ultrasound. Although bath temperature increased according to the ultrasound intensity, control studies in papillary muscles (n = 24) on the correlation between contractile parameters and temperature revealed that bulk heating could not account for the positive inotropic action with ultrasound. These data confirm the inotropic effect of continuous wave ultrasound on myocardial tissue and point to the possibility of applying this phenomenon therapeutically.

Acute liver biopsy lesions in early autoimmune ("lupoid") chronic active hepatitis.

We studied two female patients with autoimmune ("lupoid") chronic active hepatitis whose liver biopsies at initial presentation showed the unusual features of an acute hepatitis. Centrilobular hepatocyte swelling and multinucleation, acidophilic degeneration, cholestasis, mild fatty change and bile duct damage in one case resembled lesions of non-A, non-B hepatitis. Lobular and portal infiltrates of plasma cells with piecemeal necrosis suggested transition to chronicity as well as an autoimmune component. This was additionally supported by the presence of hypergammaglobulinemia and auto-antibodies in both patients. We conclude that liver biopsy features in the acute presentation of lupoid hepatitis may be difficult to distinguish from those seen in acute hepatitis due to virus or drugs.

Regional myocardial blood flow during pericardial tamponade.

The relative changes in myocardial blood flows within different parts of the heart were measured in anaesthetized thoracotomized dogs during and following effusive pericardial tamponade. Blood flows measured in a group of animals bled to the same arterial hypotensive levels served as experimental controls. The results demonstrate that regional myocardial blood flows to all areas were severely reduced during tamponade. Regional differences in the relative responses were evident; right and left atrial flows decreased more than left ventricular or septal flows which in turn decreased more than right ventricular endocardial flows decreased more than epicardial and the flow within the left side of the septal wall decreased more than the right. Although decreases in aortic pressure and ventricular volumes can account for some of these changes in flow seen in tamponade, alterations in extravascular compression appear to further reduce the myocardial perfusion and may be responsible for the differences in regional responses. In further experiments when the pericardial cavity was drained following 2 h of tamponade, a hyperemic response was seen throughout the heart indicating that the myocardial flow during tamponade may have been insufficient to meet the cardiac demands. In conclusion tamponade appears to result in a disproportionate decrease in myocardial blood flow to various parts of the heart which cannot be explained on the basis of a decrease in blood pressure or a reduction in ventricular volume.

Effect of brief ultrasound exposure on post-tetanic potentiation in cardiac muscle.

The effect of a short 4 second ultrasound application (1.0 W/cm2 sATA at 963 KHz) on the post-tetanic-potentiation of isolated isometrically contracting rat papillary muscle has been evaluated. Post tetanic-potentiation was produced in hypoxic isolated papillary muscle by interrupting the control stimulation rate of 6/minute with 10 stimulating pulses at 0.2 sec intervals for one cycle. Ultrasound application varied from one second prior to the stimulating train to a period covering the entire train. Ultrasound application just preceding and impinging upon the pulse train, enhanced post-tetanic-potentiation contractions. However, delay in ultrasound application and covering the stimulating pulse train, reduced post-tetanic-potentiation contractions. These data suggest that a window exists for the effects of ultrasound on contracting myocardium which may be used to probe critical events in the cardiac cycle.

Changes in the distribution and composition of plasma high density lipoproteins after ingestion of fat.

Following ingestion of a fatty meal there is an increase in concentration of phospholipids and proteins in the plasma high density lipoproteins (HDL). To evaluate the resulting changes in HDL subclasses, the plasma HDL of six subjects were analyzed 4 to 8 h after ingestion of 100 ml of corn oil or 80 ml of corn oil with four eggs. Isopycnic density gradient ultracentrifugation of fasting plasma showed two broad components of HDL: a major peak of density (d) 1.11 to 1.17 g/ml (HDL3) and a smaller peak of d 1.07 to 1.11 g/ml (HDL2). Following ingestion of either type of fatty meal, there was an increase in lipoprotein mass in both peaks of HDL and their centers of mass were shifted to lower density (1.140 leads to 1.120 to 1.130 g/ml; 1.095 leads to 1.090 g/ml). Calculation of changes in HDL concentration (lipemic minus fasting) showed that the alterations in density gradient profile were due to a major increase in lipoproteins of d 1.102 to 1.137 g/ml, a smaller increase in a separate lipoprotein peak of 1.080 to 1.102 g/ml, and a small decrease in lipoproteins of d 1.137 to 1.165 g/ml. Redistribution of HDL mass into larger, less dense lipoproteins was also demonstrated by agarose gel chromatography or by minimal spin density gradient ultracentrifugation in a vertical rotor. The increase in mass of 1.080 to 1.102 lipoproteins was largely due to increased concentrations of phospholipid, cholesterol ester, and apoA-I, while the increase in 1.102 to 1.137 lipoproteins was due to increased concentrations of apoA-I, apoA-II, phospholipids, cholesterol, and cholesterol esters. Analytical ultracentrifugation of representative samples within these density intervals showed lipoprotein species with molecular weights and sedimentation coefficients, respectively, of 378,000, 5.8 (d 1.080 to 1.095); 248,000, 3.5 (d 1.110 to 1.120); and 173,000, 1.6 (d 1.135 to 1.150). Polyacrylamide gradient gel electrophoresis showed that the 1.080 to 1.102 lipoproteins contained a single lipoprotein band of diameter approximately 10.7 nm; the 1.102 to 1.137 lipoproteins contained a single band which varied in size fro 10.0 to 9.2 nm: and the 1.137 to 1.165 lipoproteins contained three species of diameters approximately 9.2, 8.8, and 8.2 nm. Within density intervals, the molecular weights, sedimentation coefficients, and diameters of the different lipoproteins were similar in fasting and lipemic plasma. Calculation of average molecular compositions shows that the major incremental HDL of d approximately 1.12 g/ml could be derived by addition of lipids to the largest species of fasting HDL3. Within density intervals, the particle contents of apoA-I and apoA-II were unchanged during lipemia, suggesting that apoprotein transfer causes interconversion of existing HDL species or formation of new particles with the same content of apoA-I and apoA-II as existing species.

Effects of hydrogen peroxide on isolated myocardium.

In a preliminary series of experiments, the mechanical responses of myocardium to dilute solutions of hydrogen peroxide were examined in 19 isolated rat papillary and 25 human atrial muscles under normoxic and hypoxic conditions. When a single dose (0.5 to 1..0 ml) of 3% hydrogen peroxide [final concentration 0.01% to 0.02%] was added to normoxic muscle, developed force rose significantly [P less than 0.05] followed by a gradual increase in resting force resulting in contracture. A similar result was obtained in normoxic hypodynamic human atrial muscle. Under hypoxic conditions a singly dose of hydrogen peroxide caused a significant [P less than 0.05] improvement in mechanical properties of both preparations: developed force increased while resting force decreased However, these changes were followed by a progressive irreversible contracture. In contrast, when a 0.06% solution of hydrogen peroxide was slowly infused at a constant rate [2 ml/min], human atrial muscle showed a significant [P less than 0.05] increase in developed force and a significant [p less than 0.05] decrease in resting force from the hypoxic state while the rat papillary muscle only showed a significant [P less than 0.05] increase in resting force. Contracture did not occur in either preparation. The authors conclude that controlled contact between cardiac muscle and dilute solutions of hydrogen peroxide can alter the mechanical characteristics of myocardial tissue.

A relationship between ultrasonic intensity and changes in myocardial mechanics.

The effects of ultrasound on the mechanical properties of isometrically contracting rat papillary muscle have been studied as a function of the intensity of the ultrasonic irradiation. Each muscle was subjected to irradiation at 1.1., 2.2, and 3.3 W/cm2 at a frequency of 2.3 MHz. Ultrasonic irradiation caused heating in the vicinity of the muscle; thus it was necessary to separate the pure thermal and ultrasonic effects. After irradiation the bath temperature was increased so that the muscle reached the same temperature which occurred during ultrasonic irradiation. The mechanical parameters measured during the equivalent thermal procedure were compared with the parameters during irradiation. There was a significant (p less than 0.05) decrease in resting force which was significantly different from the equivalent thermal intervention and could be related to the ultrasonic intensity. Thus, the effect of ultrasound on rat papillary consists of two components, a thermal component which affects all parameters studied and a nonthermal component which affects only the diastolic force.