The accuracy of the Dynamic Spatial Reconstructor (DSR) in the detection of moderate coronary artery stenoses was examined in 20 closed-chest dogs. Twenty-eight hollow plastic cylinders were embolized into the left coronary arteries and produced 25% to 56% reductions in arterial lumina diameter. For each dog, one three-dimensional (3-D) image of the heart was reconstructed from each DSR scan recorded during injection of contrast into the aortic root. Analysis involved blinded visual analysis by four independent observers of multiview projection images computed from the single 3-D image. Postmortem coronary angiograms of the isolated heart were considered definitive for location of the stenoses. Overall sensitivity of detection by DSR was 89% and specificity 81%. Sensitivity of detecting stenoses greater than or equal to 50% was 98%. Receiver operating characteristics (ROC) analysis showed that detection of stenoses in the left coronary arteries is of equal sensitivity and specificity.

The natural process of endothelialization, pseudointimal formation, and connective tissue incorporation of the expanded PTFE grafts in the goat was documented through histologic examination of specimens harvested at 2, 4, 6, and 8 weeks. The goats demonstrated a progressive increase in pseudointimal pannus ingrowth from the anastomoses at a rate of 11.3 mm over a 12 week period. Histologic changes according to time of vascular graft incorporation in the goat model were found to be comparable to those of the dog, pig, and calf models reported in the literature. Platelet-inhibiting drugs, aspirin, dipyridamole, nifedipine, and ibuprofen were administered to goats after replacement of their infrarenal aorta with 5 cm of 8 mm diameter expanded PTFE grafts. The effects of the drugs on graft endothelialization and anastomotic pseudointimal formation was compared with those in the untreated control group after 12 weeks. Aspirin and dipyridamole had no detrimental effect on the healing process compared with the untreated control group. Studies with nifedipine and ibuprofen did not demonstrate a decrease in pseudointimal hyperplasia. Antiplatelet treatment resulted in no significant change in the rate of endothelialization of expanded PTFE grafts.

Nine occult carcinomas of the thyroid were found in 157 autopsies of deceased residents of Olmsted County, Minnesota, a prevalence of 5.7%. This rate is significantly lower than that reported from a previous autopsy series from Hiroshima-Nagasaki, Japan, in which similar pathologic methods and diagnostic criteria were used. Sex ratio, age distribution, and radiation exposure are considered not to explain this difference. A true difference between the Japanese and American populations with respect to the prevalence of occult thyroid carcinoma is the most likely explanation of these findings.

Three indole acids accelerated glucose uptake in the rat diaphragm. The effect of indole butyric acid was greater than that of indole propionic, which in turn was greater than that of indole acetic. The in vitro hypoglycemic potency of the indole acids paralleled their in vivo potency. Increased hypoglycemic potency may be related to the number of carbon atoms in the indole acid side chain. These and earlier observations in experimental and human neoplasia associated with hypoglycemia suggest that the neoplasm is a rich source of tryptophan material which, in the bloodstream, produces hypoglycemia by increasing the glucose uptake in peripheral muscles, and possibly in the tumor itself.

THOUGH the role of t h e h y p o t h a l a m u s in o v u l a t i o n is f a i r l y well u n d e r s t o o d in seve ra l species, 2,23,24,29 inc lud ing the cat,29,4s i n f o r m a t i o n r e g a r d i n g i ts f unc t ion in e s t r u s is i ncomple t e . L i g h t a d v a n c e s t he onse t of seasona l e s t rus in ca ts , 12,40 p e r h a p s v ia d i r e c t r e t i n o h y p o t h a l a m i c p a t h w a y s , s A n t e r io r a n d m i d v e n t r a l h y p o t h a l a m i c les ions cause ea r ly or p e r m a n e n t es t rus in t h e ferret,is,20.53 gu inea pig, 17 dog, 34 rat1,11,15,19,26,28,32,38,51--53 a n d r a b b i t u b y a

Studies on tryptophan metabolites in the blood and urine of 5 additional patients having symptoms of hypoglycemia associated with neoplasia are reported. Three patients having islet cell tumors and hypoglycemia had normal levels of tryptophan metabolites in the blood and urine during hypoglycemia. A patient with metastatic carcinoma of the breast and a patient with metastatic adrenal carcinoma also had normal values for tryptophan metabolites in the blood and urine during hypoglycemia. These patients are compared with 2 previously reported patients who had extrapancreatic neoplasms, hypoglycemia and high levels of tryptophan metabolites in the blood and urine. The findings suggest that, when a patient has high levels of tryptophan metabolites in the blood and urine during hypoglycemia, a diligent search for extrapancreatic neoplasm should be undertaken. When tryptophan metabolites in the blood and urine are normal during hypoglycemia, a careful search for an islet cell neoplasm is indicated.

Approximately fifty-seven cases in which a malignant lesion was associated with hypoglycemia in man have been reported. In thirty-two cases the lesions were of mesodermal origin and in twenty-five of epithelial origin. Fibrosarcoma was the most frequent mesodermal tumor, hepatoma the most frequent epithelial lesion in the series. In at least four instances an experimental neoplasm has been associated with hypoglycemia in animals.

1 The phrases "aldosterone secretion" or "hypersecretion of aldosterone" have been used to refer to actual meas- urements of the rate of secretion by the adrenal gland