Assessment of non-mydriatic fundus photography in detection of diabetic retinopathy.

Non-mydriatic retinal photography with later interpretation of the photographs was assessed as a screening method for the detection of diabetic retinopathy; when compared with an ophthalmologist''s clinical assessment in a random group of 62 diabetic patients it was accurate (false negative 6.8%, false positive 2%) and sensitive (sensitivity 96%, specificity 98%). The assessment of further management required based on analysis of the photographs was 96.5% in agreement with the further management suggested by the ophthalmologist after direct clinical assessment of the patient. If this technique were used to screen patients in a typical diabetic clinic the predicted positive accuracy rate would be 84% and the predicted negative accuracy rate 99.5%.     

Reparative growth in the rat thyroid

This study was designed to investigate the mitotic response to wounding in the rat thyroid. The spatial distribution of mitotic activity 48 hr after incision of the thyroid isthmus, or mere exposure of the gland (sham-operation), was assessed using a stathmokinetic technique. Incision resulted in a 66-fold increase over normal in metaphase index adjacent to the wound, falling over 2 mm to a stable 13-fold elevation. Sham-operation produced a smaller response with a complete return to normal levels over 1-1 X 5 mm. The results demonstrate that there is a dramatic localized mitotic response to wounding in the thyroid together with a smaller generalized response. Further, the response to sham-operation indicates that thyroid follicular cells respond to a diffusible 'wound hormone'. We suggest that this may be a major mechanism mediating reparative growth in this gland.     

Thermal shock hemolysis in human red cells. I. The effects of temperature, time, and osmotic stress

Thermal shock is a form of hemolysis which occurs in human red cells exposed to greater than a critical level of osmotic stress of 1.4 Osm and subsequently cooled from above about 12 degrees C to below that temperature. Higher concentrations and higher cooling rates each increase the amount of hemolysis, within limits. Incubation for varying periods in hypertonic solutions and varying temperatures of incubation affect the amount of thermal shock. The effect of cooling rate on thermal shock is independent of the period of exposure to hypertonic solutions. Thermal shock is not the cause of freezing injury in human red cells, at least above -10 degrees C.     

Vagotomy and Pyloroplasty for Gastric Ulcer

In a series of 68 patients with gastric ulcer who were treated by vagotomy and pyloroplasty there were no operative deaths, though one patient who received massive transfusions died 14 weeks later from hepatic necrosis probably associated with serum hepatitis. Four patients developed recurrent peptic ulceration requiring further surgical treatment. The clinical condition of all but three of the remainder was satisfactory after an average follow-up period of three years and two months. Of the 14 patients who presented with an acutely bleeding gastric ulcer, one subsequently required gastrectomy for continued bleeding; in all the others the immediate and long-term results were satisfactory. Of 21 patients with a “high” ulcer and 29 with combined gastric and duodenal ulceration one (4·8%) and three (10%) respectively suffered recurrences. We conclude that vagotomy and pyloroplasty is a satisfactory form of treatment for a high or bleeding gastric ulcer, but that for all other gastric ulcers some form of gastric resection is preferable.     

Light intensity and sexual maturity

There are confirmable clines, by latitude, of melanin concentration in pigmentation for man as well as other mammals and birds. This has been suggested to be, in man, a result of the importance of vitamin D synthesis which can be inhibited by darker skins in higher latitudes. Experiments on mice suggest that another mechanism may be operative; greater photic stimulation of the pineal lowers the age at first estrus and may confer a reproductive advantage in this way.