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Biomedical subjects

J E Carroll

Publications and source records attributed to J E Carroll.

At least 55 records · Page 3Linked to original sources
PubMed1984

Evaluation of monoclonal anti-A and anti-B and affinity-purified Ulex europaeus lectin I for forensic blood grouping.

Two different monoclonal anti-A and anti-B and several different affinity purified Ulex europaeus lectin I reagents were evaluated and compared with conventional anti-A and anti-B sera and Ulex anti-H for serologic properties, in inhibition tests with secretor salivas, and in elution tests with bloodstains. The monoclonal and purified reagents were found to be comparable to conventional ones, and accordingly suitable for forensic inhibition and elution procedures.

ABO Blood-Group System↗
PubMed1983

Cholesteryl hemisuccinate alters membrane fluidity, angiotensin receptors, and responses in adrenal glomerulosa cells.

We examined the effects of cholesteryl hemisuccinate on membrane fluidity and angiotensin II (AII) actions in bovine adrenal glomerulosa cells. Incubating cells with cholesteryl hemisuccinate decreased membrane fluidity and markedly inhibited AII binding. The effect on binding was characterized by a decrease in AII receptor number. The effects of AII on phosphatidyl inositol turnover and calcium fluxes, proposed intermediaries of AII actions on aldosterone secretion, were less impaired than AII binding by cholesteryl hemisccinate. AII stimulation of aldosterone secretion was preserved despite the decrease in AII binding after cholesteryl hemisuccinate treatment. These results indicate that AII binding can be dissociated from its effects on aldosteronogenesis by a reagent that alters membrane fluidity.

Adrenal Cortex↗
PubMed1983

Fatty acid oxidation intermediates and the effect of fasting on oxidation in red and white skeletal muscle.

In vitro oxidation of U-[14C]glucose-6-phosphate, 2-[14C]pyruvate, and 1-[14C]pyruvate was significantly reduced in red skeletal muscle from fasting rats. Over the same time interval of fasting, 1-[14C]palmitate oxidation remained unchanged. Pyruvate dehydrogenase activity, assayed before in vitro activation, was also reduced in red muscle. Long chain acylcarnitine and long chain acyl CoA increased over the same time period in red muscle. Changes in long chain fatty acid derivatives and pyruvate oxidation were much less dramatic in white muscle. We propose that the rise in levels of long chain fatty acid derivatives may be directly related to the inhibition of carbohydrate oxidation during fasting in red skeletal muscle.

Animals↗
PubMed1983

Skeletal muscle fatty acid oxidation during early postnatal development in the rat.

(1-14C)-palmitate oxidation in rat skeletal muscle homogenates increased only minimally from birth until 15 days of age and then increased more than five times between 15 days and adulthood. In contrast, liver oxidation of palmitate reached adult levels by 4 days of age. Although muscle carnitine concentration, carnitine palmityl transferase activity, and total muscle protein increased during the neonatal period, these changes did not completely parallel the rise in muscle palmitate oxidation. Palmityl-CoA synthetase and palmityl-CoA dehydrogenase activities also did not parallel the rise in overall palmitate oxidation.

Acyl-CoA Dehydrogenase↗
PubMed1983

Chronic valproate administration reduces fasting ketonemia in children.

We previously found that chronic administration of sodium valproate to suckling infant mice reduced plasma beta-hydroxybutyrate levels but had no effect on plasma free fatty acid or glycerol concentrations. We now report that valproate has a similar effect in children taking the drug for epilepsy. In larger doses, valproate also depleted the infant mouse liver glycogen content. These findings may relate to the hepatic toxicity of valproate. We advise caution if the drug is being considered for use in chronically malnourished children or when the caloric intake of normal children is likely to be reduced during periods of acute illness.

Child↗
PubMed1983

Increased long chain acyl CoA in Duchenne muscular dystrophy.

Compared with normal or denervated human muscle, long chain acyl CoA was increased in muscle from patients with Duchenne dystrophy. Free and short chain acylcarnitine were reduced in Duchenne muscle, whereas long chain acylcarnitine was preserved. The accumulation of long chain fatty acid derivatives may imply disruption of fatty acid oxidation.

Acyl Coenzyme A↗
PubMed1982

Lipid storage myopathy in infantile Pompe's disease.

An infant died at 8 months of age with a history of developmental regression, hypotonia, severe weakness, cardiomegaly, congestive heart failure, and hepatomegaly. A diagnosis of Pompe's disease (glycogenosis type II) was established by muscle biopsy at 5 months of age. Vacuolar myopathy involved muscle fibers of histochemical type I more than type II. Many vacuoles were filled with glycogen. In addition, increased amounts of neutral lipid were demonstrated by oil red O stain, electron microscopy, and quantitative analysis. Acid alpha-1,4-glucosidase activity was demonstrated to be deficient. Biochemical studies failed to determine the cause of the lipid accumulation, but demonstrated a low total concentration of carnitine in the muscle (6.37 nmole/mg of protein), associated with elevated activities of carnitine palmityl-transferase and palmityl-coenzyme A dehydrogenase. Palmityl-coenzyme A synthetase activity was in the normal range.

Carnitine O-Palmitoyltransferase↗
PubMed1982

Incomplete palmitate oxidation. Possible source of human myopathy.

A study of palmitate oxidation in 200 consecutive human muscle biopsy specimens showed 14 patients in whom there was abnormal, incomplete palmitate oxidation when the rate of oxidation of palmitate 14C (ul) was compared with that of palmitate 14C (at carbon 1). Five patients had denervation as a primary diagnosis, and the remaining nine had a primary muscle disease. Of this latter group, six had clinical similarities, including proximal weakness, necrotic fibers on muscle biopsy, and extreme elevations of serum creatine kinase. With one exception, lipid storage was not part of the syndrome. The possibility of incomplete palmitate oxidation due to a defect in beta-oxidation producing a human myopathy is discussed.

Adolescent↗
PubMed1982

Palmitate oxidation in human muscle: comparison to CPT and carnitine.

The evaluating of palmitate oxidation in muscle tissue may be a useful screening test for detecting defects in fatty acid metabolism in human neuromuscular disease. If the test is to be useful, it is necessary to obtain data on a wide variety of muscle illnesses for comparative purposes. We report our experience with palmitate oxidation, muscle carnitine, and carnitine palmityl transferase (CPT) activity in 148 muscles biopsies from a variety of illnesses. The efficacy of using total protein, citrate synthase, and (1-14C) pyruvate oxidation as internal references was investigated. Palmitate oxidation was significantly less than normal (P less than or equal to 0.01) in Duchenne muscular dystrophy, congenital nonprogressive myopathy, congenital muscular dystrophy, malignant hyperpyrexia, and denervation, depending on the internal reference used. Muscle carnitine levels followed a similar pattern, however, CPT activity did not. The possibility of these findings being secondary to inactivity is discussed.

Acyltransferases↗
PubMed1982

Exercise hyperventilation in patients with McArdle's disease.

This study was undertaken to determine if patients who lack muscle phosphorylase (i.e., McArdle's disease), and therefore the ability to produce lactic acid during exercise, demonstrate a normal hyperventilatory response during progressive incremental exercise. As expected these patients did not increase their blood lactate above resting levels, whereas the blood lactate levels of normal subjects increased 8- to 10-fold during maximal exercise. The venous pH of the normal subjects decreased markedly during exercise that resulted in hyperventilation. The patients demonstrated a distinct increase in ventilation with respect to O2 consumption similar to that seen in normal individuals during submaximal exercise. However their hyperventilation resulted in an increase in pH because there was no underlying metabolic acidosis. End-tidal partial pressures of O2 and CO2 also reflected a distinct hyperventilation in both groups at approximately 70-85% maximal O2 consumption. These data show that hyperventilation occurs during intense exercise, even when there is no increase in plasma [H+]. Since arterial CO2 levels were decreasing and O2 levels were increasing during the hyperventilation, it is possible that nonhumoral stimuli originating in the active muscles or in the brain elicit the hyperventilation observed during intense exercise.

Adult↗
PubMed1982

The effect of prolactin on human aldosterone-producing adenomas in vitro.

There is evidence for an unidentified aldosterone-stimulating factor of pituitary origin. We measured the effect of ovine PRL (oPRL) on aldosterone secretion by isolated cell suspensions of human aldosterone-producing adenomas (APAs) and compared it to the effects of angiotensins, ACTH, and potassium (K+). In the first APA, the aldosteronotropic action of large doses of oPRL was double that of angiotensin II (AII); the response to ACTH was triple that to AII, while K+ had a small stimulatory effect. Results with the second APA showed that physiological concentrations of oPRL caused a response nearly double that to AII, but, once again, less than the response to ACTH; K+ was inert. ACTH contamination of the oPRL preparation was too minute to account for these findings. We conclude that oPRL possesses aldosterone-stimulating activity in APAs greater than that of angiotensins and potassium, but less that that of ACTH. These data suggest a role for PRL in aldosterone secretion by aldosterone-producing adenomas.

Adenoma↗
PubMed1981

Carnitine intake and excretion in neuromuscular diseases.

Free and total carnitine serum concentrations and urinary excretion were examined in patients with various neuromuscular diseases. On a measured, low carnitine diet and during fasting, the patients did not differ from controls. Carnitine excretion in patients (3.09 +/- 1.87 mumol/kg/day) and controls (2.99 +/- 1.12) exceeded carnitine intake (patients, 2.35 +/- 0.94 mumol/kg/day; controls, 1.33 +/- 0.70). Because of heterogeneity in the patient population, carnitine excretion was assessed according to creatinine excretion, chosen as an indicator of muscle mass. Those patients with daily creatinine excretion less than 1 g/day had significantly lower carnitine excretion (106 +/- 47 versus 205 +/- 95 mumol/day, p less than 0.05), and there was a positive correlation between creatinine excretion and carnitine excretion (r = 0.82) and between muscle carnitine and carnitine excretion (r = 0.67). Urinary clearances for acylcarnitine were 10 and 20 times higher than those for free carnitine. Two patients with carnitine palmityl transferase deficiency were similar to the other patients, but the carnitine-deficient patient lost excessive carnitine during fasting, probably secondary to elevated acylcarnitine fraction in the blood.

Adolescent↗
PubMed1981

Riboflavin-responsive lipid myopathy and carnitine deficiency.

We used riboflavin to treat a patient with lipid myopathy, reduced exercise capacity, intolerance to fasting, and reduced concentrations of carnitine in muscle and serum. Although carnitine concentrations did not change, exercise capacity doubled, and response to fasting improved. Muscle enzyme assay showed that palmityl CoA dehydrogenase activity with and without added flavin adenine dinucleotide (a riboflavin product) was normal. Another riboflavin derivative, electron transfer flavoprotein, could be the site of the defect.

Acyl-CoA Dehydrogenase↗
PubMed1981

Chronic valproate administration produces hepatic dysfunction and may delay brain maturation in infant mice.

Infant mice (2 to 4 days old) received valproate (100 or 200 mg per kilogram body weight) subcutaneously once daily for 5 days. Both dosages decreased plasma beta-hydroxybutyrate levels to about one-third of the control value, in the face of normal free fatty acid and glycerol levels. At 200 mg per kilogram of valproate, there were significant decreases in brain weight and brain K content. Both doses produced metabolite changes in brain compatible with a reduced metabolic flux through the glycolytic pathway and the citric acid cycle. Valproate reduced brain aspartate but did not increase brain GABA levels in infant mice. At 200 mg per kilogram of valproate, brain glutamate decreased and taurine levels increased. Two hundred milligrams per kilogram of valproate caused a profound reduction of liver glycogen stores. The apparent decrease in cerebral metabolic rate, reduced glutamate and aspartate, and increased levels of taurine in brain may relate to the anticonvulsant action of valproate. Together with the decreased brain weight and K content, the findings are also compatible with maturational delay. Decreased ketonemia and liver glycogen content may relate to the hepatic toxicity associated with valproate administration in infants and children.

3-Hydroxybutyric Acid↗
PubMed1980

Endurance exercise training in a patient with central core disease.

A 36-year-old man with central core disease underwent endurance exercise training on a bicycle ergometer for 9 months. The training resulted in an increase in work capacity and maximal oxygen consumption of approximately 50%. Further improvement in his exercise capacity seemed limited by the primary disease. These results suggest that some neuromuscular disease patients may benefit from endurance exercise training.

Adult↗