Biomedical subjects

S M Joubert

Publications and source records attributed to S M Joubert.

At least 109 records · Page 6Linked to original sources

PubMed1981

Hyperthyroidism in gestational trophoblastic neoplasia.

The thyroid status of twenty-seven African patients with gestational trophoblastic neoplasia (GTN) was studied. Fifteen patients were found to be biochemically hyperthyroid (eight patients with choriocarcinoma; seven with hydatidiform mole). Of these fifteen patients, nine were clinically thyrotoxic. The most serious complication of thyrotoxicosis was life-threatening acute pulmonary oedema with associated cardiac failure. It was found that when serum levels of the human chorionic gonadotrophin (hCG) reached a level of about 0.1 X 10(6) iu/1, thirteen of sixteen patients were biochemically hyperthyroid; at serum levels of 0.3 X 10(6) iu/1 of hCG most patients were clinically thyrotoxic. A feature of hyperthyroidism associated with GTN is that whereas T4 is invariably raised the T3:T4 ratio tends to be low (0.015 +/- 005); rT3:T3 ratios were high in this group. TSH levels were not increased.

Adult↗

PubMed1980

Nuclear and cytoplasmic oestrogen receptors in human mammary carcinoma.

Methods for the measurement of cytoplasmic and nuclear oestrogen receptors (CER and NER) are described. CERs and NERs were found to be labile at ambient temperatures; the receptors are stable for up to 1 year when stored in liquid nitrogen. Over a period of 5 years, 51% of the breast adenocarcinomas examined in women proved to be positive for CER; four adenocarcinomas of the breast obtained from men were all positive for CER; in those tumours examined for both CER and NER, 46% proved positive for CER and 30% positive for NER; no tumour was found to be positive for NER and negative for CER. In older female patients, the percentage of patients positive for oestrogen receptors increased and they were present in higher concentrations; in younger Indian women the same tendency was observed. The percentages of receptor-positive tumours in Indians, Blacks and Whites are similar. Neither the stage of the tumour nor the presence of nodal metastases influenced receptor positivity; there was no significant difference in the time to recurrence between receptor-positive and receptor-negative patients in the small number with reliable follow-up data.

Adenocarcinoma↗

PubMed1978

Radioimmunoassay of serum ferritin.

Purified human spleen ferritin was labelled with 125I. On Sepharose 6-B gel filtration four species of labelled products were separated: a component with a higher molecular weight than ferritin; a component which is eluted in the same volume as unlabelled ferritin; and two labelled compounds with molecular weights lower than ferritin. When these labelled materials were used in a double antibody radioimmunoassay, the high molecular weight fraction showed variable and high non-specific binding and was poorly displaced by unlabelled ferritin; the fraction behaving like true ferritin gave good standard curves and showed non-specific binding of less than 1%. The remaining two components showed poor binding to rabbit antiferritin. Using labelled material from the second fraction, a double antibody radioimmunoassay capable of measuring 2 microgram ferritin protein/litre of serum was developed. Inter- and intra-assay variation was between 3% and 8% over a concentration range of 0 to 250 microgram ferritin protein/litre. Good agreement between serum ferritin levels assayed by the present method and by an immunoradiometric method was obtained. Labelled ferritin was stable for at least six weeks. The simplicity of the methodology makes it possible to assay serum ferritin in large batches.

Ferritins↗

PubMed1976

Basal serum gastrin levels in normal subjects and in various gastro-intestinal conditions.

A total of 1 035 routine serum gastrin investigations was undertaken with a commercially available kit. Levels in 49 normal subjects were similar to those found in 200 patients with duodenal ulcertaion, in 42 patients with gastric ulcers, in 9 patients with carcinoma of the stomach, in 55 patients with chronic alcohol-induced pancreatitis, and in 27 with iron deficiency anaemia. Significantly raised levels of serum gastrin were found in 32 patients with megaloblastic anaemias, where the rise in serum gastrin concentration correlated with a fall in maximal acid output, and in 14 patients with complete vagotomies. It is suggested that a level of less than 2 mEq/h of acid after insulin and a raised serum gastrin level are useful criteria of completeness of vagotomy.

Adult↗

PubMed1975

Ascorbate status of patients with porphyria cutanea tarda symptomatica and its effect on porphyrin metabolism.

The ascorbate status and the effect of loading doses of ascorbic acid (1,5 g per day by mouth for 7 days) on the porphyric process were studied in 7 black men with porphyria cutanea tarda symptomatica. It was found that the ascorbate stores were depleted in these patients as judged by serum and leucocyte ascorbate levels. Temporary repletion of the ascorbate stores was effected by the loading doses of ascorbic acid: Serum iron concentrations increased in 6 patients; urinary iron excretion showed small peaks a few days after ascorbic acid therapy commenced; haemoglobin concentration was not affected; excessive amounts of oxalate were excreted in the urine; neither total urinary porphyrin excretion nor the composition of the urinary porphyrins was affected in a way which could be related to ascorbate therapy. Further evidence that ascorbate depletion is not important in the induction of porphyria was found when the ascorbate status of siderotic rats, rendered porphyric by hexachlorobenzene-feeding, was examined. Stores of ascorbate and the oxidative catabolism of ascorbate were not different in the prophyric rats as compared with normal litter mates.

Adult↗

PubMed1974