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Biomedical subjects

T G Brien

Publications and source records attributed to T G Brien.

At least 19 recordsLinked to original sources

A simple method for the separation and quantification of urinary porphyrins.

A simple routine method for the separation and quantification of urinary coproporphyrin and uroporphyrin using anion-exchange resin columns is described. The coproporphyrin is first removed from the urine by ether extraction. The anion exchange resin column is then used to isolate the uroporphyrin from the aqueous residue. The proposed method is compared with an existing method developed by Rimington in terms of recovery and reproducibility. Results from 15 urine specimens analysed by both methods are compared. The proposed method yielded lower values for coproporphyrin and higher values for uroporphyrin than the established method, but there was a good correlation between the two methods. This and its relative simplicity make it suitable for routine use.

Chromatography, Ion Exchange↗

Human corticosteroid binding globulin.

The literature on corticosteroid binding globulin (transcortin) in the human is reviewed under the following headings: physicochemical properties, biosynthesis, measurement, and physiological, pharmacological and pathological variations with particular emphasis of the effects of pregnancy and oral contraceptives. Finally, the physiological implications of corticosteroid binding globulin are discussed.

Adrenal Cortex Diseases↗

Longitudinal study of the free cortisol index in pregnancy.

Total plasma cortisol, the 'cortisol resin uptake ratio' (cortisol RUR), and 'free cortisol index' (FCI) were estimated in 23 pregnant women from 12 weeks to term and at six weeks post partum. Total plasma cortisol rose continually throughout pregnancy; the cortisol RUR rose up to 20 to 23 weeks and then fell slowly and the FCI also rose although more slowly than the total cortisol. All parameters fell to non-pregnant levels at six weeks post partum. It is confirmed that a true rise in metabolically active cortisol occurs during pregnancy.

Female↗

The adrenocortical status of patients with thyroid disease.

Plasma cortisol, cortisol resin uptake ratio and free cortisol index was measured in twenty-seven euthyroid, ten hypothyroid and fifteen hyperthyroid subjects. No difference was observed between euthyroid subjects and patients with thyroid disease for any of the three parameters tested. The significance of these findings is discussed in the light of earlier reports linking thyroid activity with the levels of corticosteroid binding globulin.

Humans↗

Cortisol metabolism after oral contraceptives: total plasma cortisol and the free cortisol index.

Plasma concentrations of cortisol, cortisol resin uptake ratio (cortisol RUR) and free cortisol index (FCI) were measured in women taking combined oestrogen/progestogen and progestogen only oral contraceptives. Compared to control subjects, women taking the combined pill had elevated cortisol and cortisol RUR values in both the morning and afternoon but there was no significant change in FCI. Women taking the progestogen only pill had essentially normal levels of cortisol, cortisol RUR and FCI at both times of the day. As far as could be judged, diurnal variation of total cortisol and FCI remained unimpaired in women taking both types of pill. The FCI measurements indicated that there was no significant increase in metabolically active cortisol in women taking either the combined oestrogen/progestogen or the progestogen only type of oral contraceptive.

Contraceptives, Oral↗

New radioisotope test for detection of deep venous thrombosis in the legs.

A radiopharmsceutical product, labelled macroaggregates of albumin (M.A.A.), which is in use as a lung scintiscanning agent has been noted to have an affinity for venous thrombi. With this material and an inexpensive portable scintillation detector we have attempted to diagnose and localize thrombi in leg veins. The procedure is performed at the bedside and the result is available in 30 minutes. Thirty-one patients with clinical evidence suggestive of deep venous thrombosis in the legs were studied by the radioisotope method and by phlebography. There was agreement in 18 of 21 legs shown to contain thrombus on phlebography and in 9 of 10 legs shown to be free of thrombosis on phlebography. There was, however, lesser agreement on the site of thrombosis between the two methods. The ease of performing the test combined with the rapidity of obtaining results and accuracy in diagnosis suggests that the test has a clinical application.

Adolescent↗