Diethylstilbestrol treatment modulates the enzymatic activities of phosphatidylcholine biosynthesis in rooster liver

The effect of diethylstilbestrol injection on the activities of phosphatidylcholine biosynthetic enzymes in rooster liver has been determined. Choline kinase activity was stimulated within 4 h after the first hormone injection. By the third day enzyme activity reached 5.47 nmol . min-1 . mg-1 protein compared to control values (1.83 nmol . min-1 . mg-1 protein) which were unchanged during the the experiment. CTP : phosphocholine cytidylyltransferase activity was unaffected until Day 3 when its activity was 50% that of control values. When assayed in the presence of exogenous phospholipid, no significant change was noted in cytidylyltransferase activity. The activity of CDPcholine : 1,2-diacylglycerol phosphocholinetransferase was not altered by the hormone injections. The activity of phosphatidylethanolamine-N-methyltransferase gradually increased so that by Day 3, the enzyme activity was elevated 2-fold (0.12 to 0.24 nmol methyl group transferred per mg microsomal protein). These results are consistent with earlier in vivo studies (Vigo, C. and Vance, D.E. (1981) Eur. J. Biochem., in the press) that indicated a stimulation of phosphatidylcholine biosynthesis via CDPcholine during the first 2 days of diethylstilbestrol injection and inhibition on the third day.     

Laser treatment for carcinoma of the bronchus.

Laser treatment in carcinoma of the bronchus is essentially palliative and is suitable for only a few patients. Patients selected for laser treatment must have predominantly endobronchial growth with normal bronchial anatomy still identifiable and symptoms due to the obstruction or to haemoptysis. A total of 34 patients with carcinoma of the bronchus were treated with argon gas or neodynium yttrium aluminium garnet crystal lasers. Good palliation was obtained in just over half the cases of partial obstruction of the trachea or main bronchus, but best results were obtained in lesions of the trachea or main carina. Re-expansion of the collapsed lung was achieved in some cases but with considerable risk of pneumonia. Haemoptysis was controlled at least partly in several cases. Laser treatment has the advantage of having no toxicity or dose limit and may be used in cases of poor respiratory function. The procedure was better tolerated than radiotherapy or chemotherapy and its relatively lower cost may justify setting up laser units in major cities.     

Nutrient uptake by potato crops grown on two soils with contrasting physical properties

Potatoes were grown on two contrasting soils but in adjacent sites to investigate the effect of soil type on tuber production, nutrient uptake and nutrient inflow rates (uptake rate per unit length of root). The year of the study was wetter than normal. Tuber growth, root growth and nutrient uptake were all greater on the coarse rather than the fine-textured soil. However there was no difference in nutrient inflow rates between plants growing in the two soils. Therefore, it was concluded that the crop on the finer textured soil did not have an adequate nutrient supply, particularly of N, relative to the crop on the coarser-textured soil. The reasons for the low supply of nitrogen in the fine textured soil are not clear, but it might have been due to the smaller root system or to enhanced losses of nitrogen by denitrification caused by the combination of soil physical properties and poor drainage in a wet year.