PubMed Health⌕ Search

Biomedical subjects

F J Dryburgh

Publications and source records attributed to F J Dryburgh.

30 records · Page 2Linked to original sources

Comparison of aminohydroxypropylidene diphosphonate, mithramycin, and corticosteroids/calcitonin in treatment of cancer-associated hypercalcaemia.

Thirty-nine patients with cancer-associated hypercalcaemia were randomly allocated to receive aminohydroxypropylidene diphosphonate (APD), mithramycin, or corticosteroids and salmon calcitonin. Corticosteroids/calcitonin had the fastest calcium-lowering effect, owing mainly to an acute reduction in renal tubular calcium reabsorption; continued therapy over 9 days failed to suppress accelerated bone resorption, however, and most patients remained hypercalcaemic. Mithramycin also substantially reduced serum calcium within 24 h. A further dose on day 2 generally controlled hypercalcaemia until day 6 by reducing both bone resorption and renal tubular calcium reabsorption. By day 9, however, about 50% of the mithramycin-treated patients had started to relapse as bone resorption increased again. With APD serum calcium levels fell more slowly but progressively owing to effective suppression of bone resorption; by day 9 the control of hypercalcaemia was significantly better than in the other treatment groups. Symptoms of hypercalcaemia were greatly relieved, especially by APD.

Calcitonin↗

Hypercalcaemia of malignancy: evidence for a nonparathyroid humoral agent with an effect on renal tubular handling of calcium.

The renal handling of calcium was examined in 31 patients with hypercalcaemia of malignancy. Results were compared with those from patients with primary hyperparathyroidism, and normal controls rendered hypercalcaemic by calcium infusion. On relating the urinary calcium excretion indices to serum calcium values, inappropriately low rates of urinary calcium excretion were generally found in patients with malignancy associated hypercalcaemia. Further, the pattern of urinary calcium excretion in these subjects was similar to that found in patients with primary hyperparathyroidism. These observations suggest that, in many solid tumours, the development of hypercalcaemia may be attributable to a humoral mediator with a parathyroid hormone-like effect on renal tubular calcium reabsorption. The relatively frequent occurrence of hypercalcaemia in malignant disease thus may be partially explained by the presence of this humoral agent, which may impair the renal excretion of an increase in filtered calcium load, whether due to bone metastases, or humorally mediated osteolysis.

Adult↗

Emergency biochemistry services--are they abused?

An out-of-hours emergency biochemistry service, which allows access by all medical practitioners of varying experience within a hospital, can lead to overuse or even abuse of limited and costly facilities. When the workload increases, problems of staffing a voluntary (but paid) working rota may emerge. An industrial dispute involving medical laboratory scientific officers (MLSOs) caused the role of the emergency service to be examined and alternative regulating mechanisms to be tested. Experience at Glasgow Royal Infirmary between 1974 and 1981 has been reviewed. From 1977 to 1979, when clinicians (usually junior) arranged analyses directly with the MLSOs, test numbers increased by about 26% per annum. This was not associated with any concomitant increase in the range of analyses offered. During a five-week period in 1980, consultant clinicians had to contact a consultant clinical biochemist to arrange all emergency analyses, and test numbers were reduced to 13% of the previous levels. Subsequently, all requests for emergency analyses were made by clinicians to laboratory medical staff, and test numbers fell to approximately 60% of 1979 levels. This requesting system is now firmly established. Continued vigilance is required to maintain the reduced level of requesting, but too great a limitation on emergency requests may cause less efficient patient management. Senior clinical staff should be encouraged to take greater responsibility for the use of emergency laboratory services.

Chemistry, Clinical↗

Predictive value of derived calcium figures based on the measurement of ionised calcium.

The algorithms used in this hospital to assess calcium status are calculated ionised serum calcium and the serum calcium concentration adjusted for albumin. In order to establish their clinical usefulness, they were compared with the ionised calcium concentration measured on the Nova 2 instrument in patients with various calcium and protein abnormalities. Good correlation was found between the measured and calculated values. The predictive values for the calculated results and for total serum calcium concentrations are presented. In this series, the derived values were useful in predicting the serum ionised calcium concentration of the patients studied.

Blood Protein Disorders↗

Preparation of material to control precision of calcium selective electrodes.

A simple procedure is described for the preparation of a stable precision quality control material for use in the measurement of level of ionised calcium in serum at or near the reference range. Repeat analyses on a Nova 2 ionised calcium analyser of serum pools stored at different temperatures over a period of three months showed coefficients of variation less of less than 4%.

Calcium↗

Plasma protein concentrations in hypertriglyceridaemic subjects. Effect of clofibrate and comparison with normal subjects.

Clofibrate, a widely used hypolipidaemic agent was given for twelve weeks to ten subjects with hypertriglyceridaemia. Its effect on lipoprotein-lipids and caeruloplasmin, IgA, IgM, alpha2-microglobulin and transferrin was assessed by comparing analyses at 4, 8 and 12 weeks on therapy with the means of values at two weeks before and at the start of treatment. The normal variation in plasma proteins was assessed in six healthy volunteers during the same period of time. On clofibrate, very low density lipoprotein (VLDL) cholesterol and triglyceride concentrations fell, but the concentrations of cholesterol in low density (LDL) and high density (HDL) lipoproteins showed no consistent change. Caeruloplasmin and IgM concentrations decreased significantly, IgA showed a limited falls (significant only at 8 weeks) and alpha2-macroglobulin did not change. The concentration of transferrin increased on therapy. No relationships were found between the falls in VLDL-lipid concentrations and the alterations in other plasma proteins. No significant variation occurred in the concentrations of lipids or proteins in the normal subjects during the period of study. The results indicate that clofibrate exerts general effects on protein metabolism.

Adult↗

Diagnosis of type III hyperlipoproteinemia by chromatography of plasma lipoproteins on columns containing agarose.

Agarose column chromatography has been used to separate plasma lipoproteins into very-low-density lipoproteins (VLDL), low-density lipoproteins (LDL) and high-density lipoproteins (HDL). Applied to the diagnosis of primary type III hyperlipoproteinemia, the procedure is capable of demonstrating three characteristic and specific changes from normality in the elution pattern of lipoproteins from patients with this condition. In the type III profile there is (a) incomplete separation of VLDL from putative LDL material, (b) early elution of the type III LDL with respect to a normal LDL marker, and (c) relative deficiency of type III LDL with elution characteristics of normal LDL. We advocate the use of this method in the diagnosis of type III hyperlipoproteinemia.

Adult↗