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Biomedical subjects

G S Fell

Publications and source records attributed to G S Fell.

At least 37 records · Page 2Linked to original sources
PubMed1995

Use of a stable copper isotope (65Cu) in the differential diagnosis of Wilson's disease.

1. 65Cu/63Cu stable-isotope ratios have been measured in blood serum after oral administration of the stable isotope 65Cu. The incorporation of the isotope into the plasma protein pool was followed at various times for up to 3 days. The resulting patterns of enrichment in healthy control subjects, in Wilson's disease patients and in heterozygotes for the Wilson's disease gene, were similar in appearance to those found by others using copper radioactive isotopes. After an initially high enrichment at 2 h after dosage, the Wilson's disease cases, in contrast to the control subjects, did not show a secondary rise in isotope enrichment of the plasma pool after 72 h, demonstrating a failure to incorporate copper into caeruloplasmin. The Wilson's disease heterozygotes had variable degrees of impairment of isotope incorporation, not always distinguished from those of control subjects. 2. The stability of the isotope also permits the copper tracer to be followed for a longer period. Ten healthy subjects were studied for over 40 days, allowing the biological half-time of an oral dose of copper to be determined (median 18.5 days, 95% confidence interval 14-26 days). Known heterozygotes for the Wilson's disease gene were found to have a significantly increased biological half-time for removal of copper from the plasma pool (median 43 days, 95% confidence interval 32-77 days). 3. The incorporation of 65 Cu in patients with diseases of the liver (other than Wilson's disease) was found to be similar to that in control subjects, aiding differential diagnosis.

Adolescent↗
PubMed1995

Determination of aluminium in serum, dialysate fluid and water by inductively coupled plasma optical emission spectrometry.

Methods for the determination of aluminium in serum, dialysate fluid and water by inductively coupled plasma optical emission spectrometry are described and validated. Aluminium was measured at 167 nm using an argon purged monochromator. Matrix effects in serum and dialysate fluid were overcome by using an yttrium internal standard. Serum was found to have a complicated background in the region of 167 nm: careful selection of the wavelength used for background correction is therefore a pre-requisite for accurate analysis. The method for serum was validated by comparison with electrothermal atomization atomic spectrometry and the limit of agreement determined to be +/- 0.3 mumol/L. Routine performance in a quality assessment scheme has been highly satisfactory for a period of 1 year. The method is ideal for fast and accurate monitoring of patients potentially at risk from aluminium toxicity.

Aluminum↗
PubMed1994

Selenium and glutathione peroxidase status in paediatric health and gastrointestinal disease.

To examine the effect of paediatric GI disease on selenium concentration in plasma and glutathione peroxidase activity in plasma and red cells, results in children with Crohn's disease (n = 39), cystic fibrosis (n = 14), intractable diarrhoea (n = 13), and biliary atresia (n = 10) were compared with those from 86 healthy children undergoing routine operations. In Crohn's disease, plasma selenium concentrations were rarely low, but glutathione peroxidase activity was increased in the plasma and reduced in the red cells. Selenium concentration and glutathione peroxidase activity increased with steroid treatment but decreased with a selenium-deficient elemental diet. Plasma selenium concentration was normal in children with cystic fibrosis but very low in severely malnourished children with biliary atresia and intractable diarrhoea. Selenium concentration and glutathione peroxidase activity should be monitored in children with severe malnutrition or requiring prolonged nutritional support. Supplementation is recommended in cases of severe selenium depletion.

Adolescent↗
PubMed1994

The relationship between micronutrient depletion and oral health in geriatrics.

Changes in the oral microbial flora, some of which are related to mucosal disease, have been detected in the elderly, but the causes are not fully understood. This study has examined the possible role of micronutrient depletions in the reduced colonisation resistance and oral infection exhibited by some elderly subjects. The oral health, oral microbiology and micronutrient status of 37 geriatric patients aged 65-91 years (mean 81 years) were examined. Ten of the patients had no oral mucosal disease. Mucosal pathology in the remainder included erythema (27%), denture stomatitis (24%), angular cheilitis (16%) and atrophic glossitis (41%). Those with mucosal pathology had significantly lower serum iron concentrations (P = 0.02). Serum or plasma concentrations of zinc, copper, selenium, C-reactive protein, transferrin, caeruloplasmin, albumin, vitamin A and vitamin E were not significantly different between those with oral disease and those with healthy mouths. Similarly, activity of the selenium-containing enzyme, red cell glutathione peroxidase, did not differ significantly between the two groups. In both groups, plasma selenium concentrations (82%), red cell glutathione peroxidase activity (47%), plasma zinc concentrations (58%) and albumin concentrations (44%) tended to be below the lower limit of the reference interval. The influence of subclinical infection on these values is discussed.

Aged↗
PubMed1994

Copper associated childhood cirrhosis.

Several papers have reported severe liver disease in association with massive hepatic copper accumulation, which do not seem to be either of the recognised copper associated liver diseases, namely Wilson's disease and Indian childhood cirrhosis. A further case is reported in which novel copper kinetic studies were carried out using the stable isotope 65Cu, showing that this patient did not suffer from Wilson's disease. It is suggested that these cases can be divided into two groups on the basis of age, clinical course, and history of excessive copper ingestion. The benefits of using 65Cu for in vivo studies of copper metabolism is discussed.

Bangladesh↗
PubMed1993

Arrhythmia prophylaxis after coronary artery surgery. A randomised controlled trial of intravenous magnesium chloride.

One hundred and thirty patients undergoing elective myocardial revascularisation were randomised to receive an intravenous infusion containing either 50 mmol magnesium chloride or placebo during the first 48 h following surgery. Magnesium was given to 66 patients and a placebo infusion to 64 patients. Postoperative serum magnesium concentrations fell in the placebo group (from 0.83 +/- 0.06 to 0.79 +/- 0.11 mmol/l) but were elevated in the magnesium group (from 0.82 +/- 0.05 to 1.2 +/- 0.25 mmol/l). In total, 35 patients (26.9%) had a supraventricular arrhythmia, of which 11 were in the magnesium group (16.7%) and 24 (37.5%) in the placebo group (P = 0.013). Three patients in the magnesium group had an episode of ventricular fibrillation and three patients in the placebo group had frequent ventricular ectopics. There was one death in the magnesium group associated with a perioperative myocardial infarction. This study shows that intravenous magnesium supplements reduce the incidence of supraventricular arrhythmias following coronary artery surgery.

Aged↗
PubMed1993

Mononuclear blood cell magnesium in older subjects: evaluation of its use in clinical practice.

Serum and mononuclear blood cell (MBC) magnesium were measured in 24 healthy community subjects, average age 76 years (67-93), and in 21 ill hospitalized subjects, average age 79 years (65-90). MBC magnesium, expressed as mumol/mg protein, was significantly lower in the in-patient group (P < 0.001), but tended to be higher in the same group when expressed as fmol/cell (not significant). Further samples from community subjects on the same day, and again at 7 days, revealed coefficients of variation for intrasubject analysis of 12% and 22%, respectively (fmol/cell). The equivalent intrasubject values for serum were 2.8% on the same day and 4% at 1 week. MBC magnesium values for inpatients were probably distorted by changes in cell size and cell protein content caused by illness. Biological variability and the effects of illness on the composition and size of cells seem to limit the usefulness of MBC magnesium measurement as a clinical tool for assessment of body magnesium status.

Aged↗
PubMed1992

DNA-based presymptomatic diagnosis of Wilson disease.

Investigation using DNA markers in a family with Wilson disease revealed that an apparently normal child of 10 years of age with non-diagnostic copper biochemistry had the disease. The procedure used linked restriction fragment length polymorphic markers. Demonstration of increased liver copper concentration from a liver biopsy confirmed the diagnosis and the child was started on chelation therapy. Two other asymptomatic siblings were shown, using the same techniques, not to have the disease. Similar analysis was carried out on another family with just one index case.

Chromosomes, Human, Pair 13↗
PubMed1992

Autonomous hyperparathyroidism not associated with increased aluminum absorption.

A single 6-g dose of aluminum hydroxide was given to eight patients on regular hemodialysis before and 3 days after parathyroidectomy (PTX). Serum aluminum levels were measured before and after 5 h after ingestion of aluminum hydroxide to examine indirectly the effects on absorption of aluminum from the gastrointestinal tract of both high and low parathyroid hormone (PTH). Plasma PTH levels fell significantly from 2,724 +/- 1,830 ng/l (mean +/- 1 SD) before PTX to 352 +/- 63 ng/l after PTX. However, no significant change was detected in serum aluminum levels before or after PTX (1.45 +/- 0.96 to 1.92 +/- 0.88 mumol/l before PTX; 2.02 +/- 1.41 to 2.89 +/- 1.19 mol/l after). These findings indicate that in patients with chronic renal failure, high plasma levels of PTH are not associated with significant increases in serum aluminum concentrations after ingestion of a large quantity of aluminum hydroxide. Parathyroid hormone may not enhance intestinal absorption of aluminum in humans.

Adult↗
PubMed1991

Ranitidine suppresses aluminium absorption in man.

1. Intragastric pH monitoring was performed before and after the single-blind administration of ranitidine or placebo (saline) in eight healthy subjects and four patients with end-stage renal disease who were on regular haemodialysis. 2. The subjects were studied on two occasions and were given aluminum hydroxide (1185 mg) orally 90 min after the administration of ranitidine or saline. 3. Plasma aluminum concentrations and, in normal men, urinary excretion of aluminum were monitored before and after the oral aluminum load. 4. Intragastric pH increased significantly with ranitidine but not with placebo (P less than 0.001). Urinary aluminum excretion increased significantly after the administration of aluminum hydroxide during the placebo phase (P less than 0.001) but not during the ranitidine phase. Plasma aluminium concentrations were higher in the patients with renal failure than in the normal subjects (P less than 0.05), but were unchanged in both groups after the oral aluminium load. 5. This study shows that gastric pH is an important factor in the modulation of aluminum absorption in man, and indicates that reducing gastric acid secretion with ranitidine may reduce the toxicity of orally administered aluminium compounds.

Adult↗
PubMed1991

Aluminium uptake by intestinal cells: effect of iron status and precomplexation.

The investigation of different aluminium-binding agents and metabolic conditions that might act as critical factors in modulating aluminium absorption could yield valuable information in the understanding of aluminium gastrointestinal absorption. We evaluated the effect of iron depletion in aluminium uptake and the role of transferrin and citrate in aluminium incorporation by the intestinal epithelial cell line RIE1. Both complex, aluminium-citrate and aluminium-transferrin were prepared in a molar ratio of 2:1; both facilitated the aluminium uptake although a greater aluminium incorporation was found when aluminium was administered as aluminium-transferrin. This difference became even greater in the iron-depleted cells (normal cells vs iron-depleted cells): 7.7 +/- 1.4 versus 30 +/- 5.6 ng Al/micrograms DNA (P less than 0.05). From these and previous data it is possible to speculate that iron status could modulate the intestinal uptake of aluminium and that both transferrin and citrate would act as effective carriers in the incorporation of aluminium into mucosal cells.

Aluminum↗
PubMed1991

Wilson's disease in Scotland.

The prevalence and clinical features of Wilson's disease in Scotland were investigated. Thirty three cases were identified but adequate information was available on only 28. In 1989, the prevalence rate was 4 per million. Ten patients with a mean (SEM) age of 18 (1.9) years presented with neurological symptoms, 12 patients aged 14 (1.7) years presented with hepatic symptoms, and six patients aged 12 (0.9) years were asymptomatic siblings of patients with Wilson's disease. Nine (56%) of the 16 patients who underwent liver biopsy on presentation were found to have cirrhosis. Penicillamine treatment was stopped in nine patients because of: abnormal peripheral blood count (6), rash (2), and patient's own choice (1). Nineteen patients were alive in 1989 -12 were well, one had chronic liver failure, four chronic neurological disabilities, and two had both chronic liver failure and neurological disabilities. Twelve patients died from: complications of chronic liver failure (2), acute liver failure (4), pneumonia associated with immobility (4), and other causes (2). Several patients who died had received incomplete medical supervision.

Adolescent↗
PubMed1991

Comparison of inorganic elements from autopsy tissue of young and elderly subjects.

Concentrations of nine inorganic elements in autopsy samples of kidney, liver, heart and skeletal muscle from 33 aged subjects, mean age 80 years, were compared with concentrations in similar samples from 12 young healthy accident victims, mean age 29 years. Tissue samples were removed within 48 hours of death and dry weight was used as a frame of reference. Potassium and magnesium were significantly lower in muscle (P less than 0.001) and heart tissue (P less than 0.001) of elderly subjects. There was evidence of accumulation of zinc in liver tissue of the elderly (P less than 0.01). Copper was significantly lower in the heart tissue of elderly subjects (P less than 0.001) whereas manganese was lower in both the heart (P less than 0.01) and the kidney tissue (P less than 0.001) of the elderly. Selenium concentrations were lower in the kidney (P less than 0.001) of the elderly. Elderly heart tissue appeared to accumulate chromium (P = 0.007) and aluminium (P less than 0.001). No significant differences were found for iron concentrations between these two populations. These major differences in tissue element concentrations between young and aged subjects merit further attention.

Age Factors↗
PubMed1990

The effects of intraoperative hypothermia and cardiopulmonary bypass on trace metals and their protein binding ratios.

The ability of intraoperative hypothermia to modify the metabolic response to cardiopulmonary bypass (CPB) was assessed by serial alterations in iron, zinc and copper, and in their molar binding ratios to their respective transport proteins, in 20 male patients under-going elective coronary artery surgery and randomised to an operative blood temperature of 28 degrees C or 20 degrees C. Decreases in serum iron and zinc concentrations, typical of the acute phase response, were preceded by early rises. Significant alterations in the metal: protein molar binding ratios preceded significant changes in the serum concentrations of the metals and occurred earliest in the zinc: albumin binding ratio, which was apparent by the time of skin incision. An intraoperative temperature of 20 degrees C modified iron and zinc concentrations and their protein binding ratios during surgery but not in the post-operative period. These early changes in trace metals and their protein binding ratios are a simple and inexpensive method of quantitating the response to surgical injury and may be useful in assessing new interventions in cardiopulmonary bypass. An awareness of the trace element response to surgical injury is essential to avoid misdiagnoses of iron deficiency anaemia or zinc deficiency.

Adult↗
PubMed1990

Wilson's disease presenting as acute fulminant hepatic failure.

A fatal case of fulminant hepatic failure in an adolescent is described. Post-mortem examination revealed the cause to be Wilson's Disease. This rare presentation is characterised by apparently atypical changes in copper metabolism. Wilson's Disease should be a differential diagnosis of any adolescent presenting in liver failure.

Adolescent↗