HYPERTHYROIDISM DUE TO A THYROTROPHIN-SECRETING MICROADENOMA

We report a 63-year-old female with a TSH-secreting pituitary adenoma causing hyperthyroidism. This case is apparently unique, and challenges the present concept of dividing patients with inappropriate TSH secretion into tumour and non-tumour groups on the basis of conventional pituitary fossa radiology.     

Induction of basal lamina formation in epidermal cell cultures in vitro

Guinea-pig epidermal cells were grown on 2 types of rat collagen substrate. The cells showed the same sort of differentiation as occurs in cells growing on rigid plastic. In addition, basal lamina formed patchily at the interface with the collagen. If the collagen was eroded away the basal lamina also disappeared.     

ULTRASTRUCTURE OF ADULT EPIDERMAL CELLS IN MONOLAYER CULTURE

SUMMARY.— Epithelial cells from adult guinea-pig and human skin were grown in monolayer culture and studied by phase contrast and electron microscopy. Significant differences were found between cells in vivo and in vitro .
Keratinocytes show a selective dedifferentiation. They retain the ability to make desmosomes, but interdigitation is reduced and the system of tono-filaments is disorganized. Mitochondria become long and even branched-while microtubules become prominent, as do lysosomes and fat droplets. Ribosomes often become arranged in polyribosomes. and channels appear in the nucleus. Melanocytes showed similar changes, and 1 produced a cilium.
Such changes should be taken into consideration when cells in dispersed culture are used experimentally.     

THE REGROWTH OF RIGHT ATRIAL NORADRENERGIC NERVES AFTER 6-HYDROXYDOPAMINE IN GENETICALLY DIABETIC MICE: EFFECTS OF INSULIN TREATMENT

1 This study examined the rate of repletion of right atrial noradrenaline levels after a single dose (100 mg/kg i.p.) of 6-hydroxydopamine (6-OH Da) in diabetic and non-diabetic mice of the C57 BL/KS db/db strain. 2 In mice which received no 6-OH Da there was no significant difference, in endogenous noradrenaline levels, between diabetic and non-diabetic animals. The depletion of noradrenaline 24 h after 6-OHDa was slightly more profound in the diabetic mice than in non-diabetic controls. Thereafter the rate of repletion of noradrenaline was more rapid in the diabetic group. 3 The normal noradrenaline content was reinstated in diabetic mice between 7 and 10 days after 6-OHDa. In the non-diabetic group levels similar to those found in untreated mice were not reinstated until 14 days after 6-OHDa. 4 Ten days after 6-OHDa right atria from diabetic mice were markedly more responsive to stimulation of the intramural noradrenergic nerves than were preparations from non-diabetic mice. 5 A group of diabetic mice was treated with insulin (10 m Units/g daily) for 6 weeks. The right atria from these animals, examined 10 days after 6-OHDa, were similar in their responses to noradrenergic nerve stimulation to the preparations from the non-diabetic mice. 6 All these groups of atria gave similar responses to exogenous noradrenaline. These findings indicate that regrowth of noradrenergic terminals after 6-OHDa was more rapid in diabetic mice than in either insulin-treated diabetic mice or non-diabetic mice.     

TRANSILLUMINATED TRACHEAL INTUBATION

We evaluated the use of an inexpensive transilluminating lightwand for tracheal intubation. Expertise in its use was acquiredquickly, thereby providing successful per-oral intubation inall patients who were able to open the mouth, irrespective ofthe view obtained of the epiglottis and larynx.     

Shelf life of cefuroxime eye-drops when dispensed in artificial tear preparations

There has recently been a clinical demand for cefuroxime formulated as an eyedrop. Cefuroxime exhibits a broad spectrum of activity against most common ocular infections and is considered to be less toxic to the compromised epithelium than some other topical antibiotics. A formulation in an artificial tear solution would be expected to enhance drug penetration by prolonging pre-corneal drug retention, and the presence of a preservative might enable a suitable formulation to be given a shelf life of more than 24 hours. This paper reports studies on the stability of cefuroxime 50mg/ml (5 per cent) in artificial tear solutions, sodium chloride eye-drops and in solutions of benzalkonium chloride, hypromellose or water for injections. Cefuroxime was assayed by high performance liquid chromatography. The method had a coefficient of variation of 0.23 per cent at the concentration investigated and recovery of added cefuroxime was 100 per cent. The preparation of cefuroxime in artificial tear solutions which were preservative free or contained benzalkonium chloride less than 0.002 per cent appeared to be physically stable. Preparation of cefuroxime in Sno Tears also produced a stable solution. This preparation can be given a shelf life of 28 days at 4C, 24 hours at 25C and 14 days if stored in a domestic refrigerator, enabling a full course of treatment to be given on a single visit to the pharmacy.