The incorporation of [3H]thymidine by rat costal cartilage in vitro was studied at different fetal and postnatal ages and the effect of partially purified human somatomedin, mouse epidermal growth factor, platelet secretion products, insulin and growth hormone on thymidine uptake by fetal cartilage was examined. Thymidine uptake in plasma-free medium was many times greater in late fetal life than after birth. The incorporation of [3H]thymidine into costal cartilage from 21-day fetuses was significantly (P less than 0.05) increased above control values in the presence of 10 micrograms somatomedin/1, and when cartilage was incubated in medium containing somatomedin and diluted human plasma there was a synergistic action. Epidermal growth factor at a concentration of 1 ng/l was a potent stimulator of thymidine uptake. Secretion products from human platelets after their aggregation by thrombin stimulated [3H]thymidine uptake at a concentration of 2% (v/v), but were inhibitory at high concentrations. High concentrations of platelet secretion products stimulated the incorporation of [35S]sulphate by cartilage. A pharmacological concentration of 10 mu. insulin/ml stimulated [3H]thymidine uptake, but not concentrations of 1 or 100 mu./ml. Growth hormone had no effect. The results showed that fetal cartilage had a greater endogenous mitogenic activity than postnatal cartilage. While somatomedins may be important in the regulation of fetal body growth, other protein growth factors also stimulate fetal skeletal tissues.

A 24-year-old female with a diagnosis of primary carnitine deficiency, a rare inherited metabolic disorder predominantly described in the paediatric literature that causes cardiomyopathy, presented for evaluation after three months of nonadherence with prescribed carnitine therapy. Initial echocardiography demonstrated severe left ventricular dilation (104 ml/m2) (normal < 76 ml/m2) with moderate systolic dysfunction (ejection fraction 40%) and severe right ventricular dilation with mild systolic dysfunction. Carnitine replacement was commenced, and a cardiac magnetic resonance imaging (MRI) performed five days later demonstrated dramatic improvement in biventricular function with normalization of left and right ventricular systolic function. To our knowledge, this is only the second case describing the rapid reversal of cardiomyopathy in an adult patient with this rare condition.

Analysis of the clinical course in 85 patients with histologically proved primary hepatocellular carcinoma showed that 73 followed the classic pattern of the disease with a rapid onset and a quick demise. Howeoer, in I2 patients the course was longer in that the duration of illness was over 2 years. This was largely accounted for by the duration of symptoms prior to diagnosis. No clinical differences could be discerned between these 12 patients and the other 73, and survival once diagnosis had been made was no different. The frequency of an underlying cirrhosis in the whole series was 58 per cent.The course of these patients differed in no way from those without cirrhosis except that the age hepatocellular carcinoma presented was older. One patient who received no specific therapy lived for 4 years from the time of diagnosis, and in each of the treatment groups there were occasional patients surviving for several years.

Recent evidence suggests that epidermal growth factor (EGF) may play an important role in the regulation of thyroid growth and function. We have examined the interaction of murine EGF (mEGF) with human and porcine thyroid membranes and compared this with the binding of bovine TSH (bTSH) using 125I-labelled hormones as tracers. The characteristics of the binding of mEGF were found to be similar for human and porcine thyroid membranes. Epidermal growth factor bound with high affinity (affinity constant = 1.4 X 10(9) l/mol); the density of binding sites was low compared with the TSH receptor. At 37 degrees C, the binding of 125I-labelled EGF was maximal at 1 h and was saturable in the presence of unlabelled EGF; half-maximal inhibition was at 1 ng EGF/tube (0.5 nmol/l) using 0.5 mg membrane protein/tube. Unlabelled bTSH had no effect on the binding of labelled EGF. Similarly, unlabelled EGF did not affect the binding of labelled TSH; hence it was concluded that mEGF and bTSH bound to independent sites. Epidermal growth factor had no effect on adenylate cyclase activity in membranes prepared from human non-toxic goitre; increasing concentrations of EGF did not affect basal, TSH-stimulated or fluoride-stimulated enzyme activity.