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The performance of a single-gap electron spectrometer for in-beam isomeric lifetime measurements on the University of Manitoba Cyclotron is described. Conversion electrons following (p, x n) reactions are detected in delayed coincidence relative to the 28 MHz proton beam bursts. An overall resolving time of 770 ps fwhm is achieved for 345 keV electrons produced in the 197 Au(p,2ne − ) 196 Hg reaction. A determination of the half-life of the 1911 keV isomeric state in 194 Hg yields T 1 2 = (4.46±0.11) ns .

An in vitro microcytotoxicity assay has been used to study the humoral immune response to human astrocytomas. Sera of 17 of 26 patients with these tumors produced significant cytotoxicity when tested against allogeneic astrocytoma cells. The cytotoxic response was found to occur both preoperatively and postoperatively without obvious relationship to the histologic grade of the patient's tumor. Three of 46 sera from normal controls and 1 of 12 sera from patients with non-neoplastic nervous system diseases were also cytotoxic in this test. Sera from each of 3 patients with non-astrocytic neuroectodermal tumors were significantly cytotoxic, while none of 4 serums from meningioma patients was positive. These results indicate that a humoral immunologic response directed against antigens present on the astrocytoma cell surface occurs in most astrocytoma patients. The use of this microcytotoxicity assay may prove helpful in the preoperative diagnosis of this tumor. Cancer 33:1512–1519, 1974.

Careful studies were made of the directional correlations between the 496 keV K-conversion electron and the 124 keV gamma ray and between the 496 keV gamma ray and the 124 keV K-conversion electron in the 620-124-0 keV cascade of 131Cs formed by the electron capture decay of 131Ba. The coefficients A22 = −0.113±0.031 and A = 44 +0.140±0.036 obtained from the K electron-gamma angular correlation measurementas and the coefficients A22 = −0.012±0.012 and A44 = +0.014±0.014 obtained from the gamma-K electron angular correlation measurements together with the previously measured1) mixing ratio for the 124 keV transition give the spin sequence 3 2 + ( M 1+ E 2) 5 2 + ( E 2+ M 1) 5 2 1 for the cascade. The experiments were performed with a system, capable of electron resolution of 5 keV FWHM at 1.0 MeV, allowing the K conversion lines to be unambiguously separated from the L lines. Evidence is presented for the presence of electric monopole E0 electric transitions in direct competition with M1 and E2 internal conversion transitions from the 124 keV level. The experiments also confirm that the 496 keV transition is predominantly M1 but establishes that it has a 23±7% E2 admixture. The new measurements together with previous measurements of the gamma-gamma angular correlation and the internal conversion coefficients give a more complete picture of the cascade.

By a combination of partition chromatography and countercurrent distribution, serine-specific transfer RNA has been obtained in essentially pure form. The methods described permit the preparation of serine-specific transfer RNA in quantity, with a purity of 95% or better.

1. IN 1897, with the consent of the Italian Government, the University Museum acquired a group of vases from a chamber tomb in Vulci. Among them was a Corinthian amphora (M.S. 552), P1. XXXII, which attracted the attention of Furtwiingler in 1905,1 was briefly described by Luce,2 and has recently been listed (775A) by Payne in his Necrocorinthia.3 The shape, as Furtwaingler first remarked, is rare, but it is not unparalleled. It corresponds to that of an amphora in Athens,4 except that it has a moulded ridge at the base of the neck, and that the profile of the rim is rounded. The illustrations will serve to supplement and somewhat alter Luce's description of the vase. The pictures in the two shoulder panels are not alike; the festal procession of the middle zone is scarcely adequately described as "human figures all marching to left"; the lowest frieze is not "the usual band of orientalizing animals," but a horse race. The neck, rim and the upper parts of the handles are covered with the same orange-brown color which is used for the figure decoration. Against this background are painted rosettes of white dots. Portions of the figures are overlaid with red but there is no white. Incised lines are abundant. The painter of the horse race seems to have begun his work in the middle of the obverse with a compact little horse; as he worked to the right, he tired of his vain repetitions and drew his horses FIG. 1.-PRIESTESS WITH SACRIFICIAL BASKETS

Reduction of the C-20 ketonic group to the 20α hydroxy and 20β epimer appears to be one of the major metabolic pathways of steroid metabolism in man. This study reports the identification of 11β,17α,20α,21-tetrahydroxy-4-pregnen-3-one and the 20β epimer isolated from extracts of the urine 1) from a man receiving adrenocorticotropin, 2) from a woman with hypopituitarism, after she had ingested 400 mg. of cortisol acetate, 3) from 3 “normal” men (a “pool”), and 4) from a normal man. These results confirm the findings of Peterson, Pieree and Kliman after administration of cortisol to normal men, and of Holness, Lunnon and Gray who found the 20β epimer after the administration of adrenocorticotropin. In addition this study reports the findings of the 20β epimers after administration of adrenocorticotropin, and both epimers in urine from normal men.

Conclusions1. Two completely depancreatized dogs given intra-peritoneal injections of serum from a dog treated over 9 months with anterior pituitary extract showed a marked decrease in the degree of the glycosuria. (2) Two completely depancreatized dogs injected with anterior pituitary extract for 30 or more days showed, after cessation of extract injection, a much less severe diabetes during fasting than before the injections. (3) The metabolic behavior of these 4 dogs was much like that of the depancreatized-hypophysectomized animal.

Urinary cyclic 3′,5′-adenosine monophosphate (cyclic AMP) was determined in two normocalcemic control groups and five groups of hypercalcemic patients. Immunoreactive parathyroid hormone was also measured by immunoassay in many of the patients. Eighteen healthy controls excreted 6.2 ± 0.5 μmoles of cyclic AMP per 24 hr; 28% excreted greater than 7.0 μmoles. Sixteen surgically proven hyperparathyroid patients excreted 7.3 ± 0.7 μmoles/24 hr, not statistically different from normal, but 73% of these patients excreted more than 7 μmoles/ hrs. Urinary cyclic AMP excretion usually decreased in these patients after surgical correction of their hyperparathyroidism. A group of four patients with suspected hyperparathyroidism excreted 5.6 ± 1.2 μmoles/24 hr, no different from either normals or surgically proven hyperparathyroid patients. Plasma parathyroid hormone was inappropriately increased for the serum calcium in all of the patients with proven or suspected hyperparathyroidism in whom it was measured...

The analysis of urinary excretory products following the administration of known compounds is one of the classical methods for the study of their metabolism. The developments inpaper chromatographic (1) and micro-analytic (2) technics and the use of glucuronidase hydrolysis (3) have considerably decreased the difficulties of investigating steroid metabolism by this method. Using these newer technics, we have studied the urinary excretion pattern of the major alpha-ketolic steroids after the administration of the six "active" adrenal cortical steroids to individuals with severe adrenal cortical insufficiency. We have found, as has been demonstrated for other steroids (4), that the major alpha-ketolic metabolites result from the reduction in ring A of the steroid nucleus to the 3-alpha-hydroxy pregnane derivatives (the socalled "tetrahydro" form) and that the hydroxyl and ketone groups on carbon atom 11 are interconvertible for corticosterone and 1 1-dehydrocorticosterone as well as for hydrocortisone and cortisone.

SEVERE hydropic degeneration of the islands of Langerhans and permanent diabetes have been produced in cats by repeated intraperitoneal injections of glucose (Dohan and Lukens, 1948). The prolonged, sustained hyperglycemia so produced was thought to be the most important factor in the production of the hydropic change and the persistent diabetes. To test further this possibility it seemed desirable to localize a sustained hyperglycemia to the pancreas or a portion of it. In this way the responses to systemic hyperglycemia might be avoided and changes found in the infused organ might be attributed to the local hyperglycemia. In the experiments reported herein, the successful infusion of a part of the pancrease with glucose usually resulted in systemic hypoglycemia and in changes in the islands of Langerhans which includes both hyperplasia and hydropic degeneration. Diabetes did not occur, nor was it expected, since only part of the pancreas was infused.

The mean daily excretion of the tetrahydro alpha-ketolic metabolites of corticosterone and cortisol was determined for 40 male subjects from multiple measurements on urine collections representing 2–16 days. Paper chromatography was used for separation, and light transmission after reaction with blue tetrazolium was used for quantitation. The means and ranges in mg/day of the corticosterone metabolites were as follows: 15 normal men, .76 (.26–1.30); 13 men with essential hypertension, .84 (.40–1.40); 6 males with nonhypertensive, nonendocrine diseases, .80 (.54–1.04); 6 preadolescent boys, .43 (.20–.82). The means and ranges of the cortisol metabolites were: normal, 3.0 (1.1–5.8); hypertension, 3.7 (2.3–6.3); nonhypertensive male patients, 4.6 (2.0–6.9); boys, 1.1 (.38–2.70). The values for the 3 adult groups did not differ significantly. The log excretion values for all 4 groups combined exhibited a linear relationship to body surface area (r = 0.68 for corticosterone; 0.86 for cortisol). There ...

Messenger RNA-directed in vitro synthesis of Escherichia coli alkaline phosphatase monomers is described. Using a cell-free amino acid incorporation system to which had been added RNA preparations extracted from E. coli constitutively synthesizing alkaline phosphatase, the monomers were synthesized from radioactive amino acids. Immediately after the period of synthesis, the radioactive monomers were captured into alkaline phosphatase dimers by adding a high concentration of non-radioactive monomers. The dimers were then purified away from the other radioactive polypeptides synthesized in the system. An RNA preparation from derepressed wild-type E. coli was active in directing monomer synthesis but RNA extracted from repressed wild-type cells was inactive. The implication of these results regarding the control mechanism of alkaline phosphatase synthesis is discussed.

SummaryRats exposed to low atmospheric pressure for more than 2 days exhibited a significant increase in adrenal weight and a significant decrease in the weight of the thymus and testes. This pattern is similar to that found following other forms of stress. No significant effect of diet upon this change was demonstrated.

IN A RECENT PUBLICATION (1) we recorded our observations upon the induction,course and pathology of the permanent diabetes that may follow a series of injections of anterior pituitary extract in dogs. In this paper we present the results of studies upon: (a) the relationship of the concentration of the blood sugar and serum fatty acids to the severity of the diabetes, insulin administration and variations in diet, (b) the urinary excretion of glucose, nitrogen and ketone bodies under thesame circumstances and (c) the respiratory metabolism. An effort has been made to present data which supplement thosealready published. Marks and Young (2) have recently summarized their observations upon various aspects of this type of experimental diabetes to which they have given the name pituitary-diabetes.

SummaryThe response of rabbits to insulin before and after the injection of diabetic serum has not, in our experience, afforded a means of distinguishing different types of diabetes. The inhibition of the response of the blood sugar to insulin in rabbits after the injection of pituitary extract has ken confirmed.