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Antioxidants which contain a thioether bond are usually more effective than the simple compounds from which they are derived. More significant is the effect of carbon black on these improved antioxidants, generally resulting in even greater protection than in the clear polymer. This is in contrast to the behavior of conventional antioxidants which do not contain a thio-bond. In all cases examined, these conventional antioxidants lose a large proportion of their effectiveness in the presence of carbon black. Recent studies concerned with the chemical nature of the carbon black surface strongly suggest the presence of reactive chemical groupings which may account for the weak antioxidant activity of some carbon blacks. Apparently the carbon black surface interacts with organo-sulfur antioxidants since this unique behavior has not been observed in other materials of comparable particle size, such as alumina, titania, or silica, nor do these materials themselves inhibit polyethylene oxidation. Thioethers and disulfides which contain no amine or phenol groups and hence no active hydrogen constitute another class of antioxidants which are unusual in that they attain a significant degree of activity only in the presence of carbon black. Although the mechanism through which these simple compounds function as antioxidants has not been established, there is considerable evidence that a relationship exists between antioxidant activity and bond dissociation energy. Some thiols may act to a slight extent as conventional antioxidants in clear polyethylene, but when carbon black is present, they appear to function through the same mechanism as do the simple organo-sulfur compounds which contain no active hydrogen. It is significant that within the general class of organo-sulfur antioxidants, alkyl compounds exhibit strong antioxidant activity in the presence of carbon black, and are often comparable with their aromatic counterparts.

A 54-year-old man presenting with fever, hepatomegaly, and weight loss was found to have acute histoplasmosis, apparently involving only the liver. The diagnosis was established by culture of liver biopsy material and elevated complement fixation titers which declined in the convalescent phase of the patient's illness. Histological examination showed only granulomatous hepatitis. The patient recovered uneventfully without the use of systemic antifungal drugs. He did receive corticosteroids for a brief period. The patient now has been followed for 3 years and remains well. A recent liver biopsy showed only minimal periportal lymphocytic infiltration. A review of the literature fails to reveal a similar case. An analogy is drawn between this case and the acute self-limited pulmonary form of histoplasmosis. Culture of liver biopsy material showing granulomatous hepatitis is recommended in all cases where the etiology is not clear from other evidence.

The use of radioactive phosphorus (32P) in combination with a miniature Geiger counter passed through the esophagoscope was evaluated in 204 tests on 198 patients during a 10-year period. In 66 patients with primary cancer of the esophagus the method was 96% accurate, and in 28 patients with gastric cancer invading from below it was 93% accurate. There were 4 falsely positive results in 27 patients with esophagitis (85% accurate), 1 in 9 cases of cardiospasm or achalasia, and 2 in 68 control cases (97% accurate). The test was especially useful in 6 cases of primary esophageal carcinoma without gross mucosal involvement and in delineating extent of esophageal involvement in gastric cancer. It is not a survey method, but may be decisive in the occasional symptomatic patient without definite roentgenographic or esophagoscopic evidence of cancer.

Fatty metamorphosis of the liver was found in an unusually large number of percutaneous needle liver biopsies in patients having mammary carcinoma with suspected metastases; this prompted a study of this abnormality in patients with cancer in general. The autopsy records of 1744 patients and percutaneous liver biopsy reports of 489 patients with malignant neoplasia were reviewed. Fatty metamorphosis was found in 66 (2.8%) of autopsies and 36 (7.3%) of liver biopsies. In cancer of the breast the incidence of fatty metamorphosis on biopsy (21.0%) exceeded that for all other cancers combined or for any other single tumor type, while at autopsy the frequency (5.9%) exceeded that of all other cancers (3.5%). In both autopsy and biopsy series there was a fatty metamorphosis ratio of 2:1 female to male patients. Of the 14 patients having mammary cancer with fatty metamorphosis on biopsy, 11 had hepatomegaly and all but one had abnormal bromsulfalein retention. Alkaline phosphatase was elevated in four, three of whom had metastases to bone. Seven of the 14 were obese and four had been treated with chemotherapeutic agents or had undergone oophorectomy. Four were diabetic; three had received steroids or androgens; one had received estrogens and one was clinically malnourished. Rebiopsy at 24 to 44 months showed no change in three and mild fibrosis in one. There is a definite increase in fatty metamorphosis of the liver in patients with carcinoma of the breast, which may account for hepatomegaly with bromsulfalein retention in such cases and be confused with metastases to the liver. The cause for this finding is unknown.

In a prospective study of 40 patients with gastric lymphoma, color photography and directed biopsy were performed routinely.Brush cytology was obtained in 20. When compared with a previous series, there was slight improvement in gross diagnosis, but the sole distinctive characteristic was a peculiar "volcano-like" ulcer crater noted in 9/30 patients with reticulum cell sarcoma. Directed biopsy was positive in 35/40 patients, and brush cytology in 4/20. Directed gastroscopic biopsy appears to be a highly accurate means of diagnosis in gastric lymphoma, in contrast to gross diagnosis by either roentgenography or gastroscopy.

Aspects of renal metabolism of fructose have been studied in rats without interference from the liver but without hypoglycemia. Data were obtained which suggest that added renal venous glucose found after injection of fructose arose nearly quantitatively from fructose. The decrease in concentration of fructose or increase of glucose on passage of blood through the kidney permitted calculation of a clearance value closely similar to the inulin/Diodrast clearance fraction of rats, suggesting that conversion of fructose to glucose may be a process connected with tubular transport. Randomization of radioactivity during conversion of fructose-6-C14 led to appreciable accumulation of label in C-1 of renal venous glucose. This was analogous to events during intestinal transport of fructose in guinea pigs, which had been shown to be caused by intermediate scission into three carbon units. A similar mechanism thus may operate in renal tissue of rats. Glomerular filtration seemed to persist after ureteral ligation, tending to explain persistence of conversion of fructose to glucose at a reduced level. No appreciable net contribution of glucose to blood by the kidney was found when no injections were given or when saline alone was administered.

To many engineers not directly concerned with the more basic theories of dielectrics behavior, and, it must be recognized, even to some persons having a good knowledge of the electrical properties of individual insulating materials, it is often difficult to understand the detailed behavior of any particular insulation system. In other papers of this tutorial session, eminent speakers, well versed in their fields, have outlined the various fundamental relationships governing the properties of materials as related to structure of the individual materials, and it is the purpose of this paper to discuss briefly some of the phenomena which arise when combinations of insulating materials are used in more practical situations, and to focus discussion on how these phenomena can be related to basic relationships already established. With this more detailed understanding, it is also possible to see what advances can be made, and in what direction, for future development work in improved composite dielectric materials and insulation systems generally.

The rate of glomerular filtration in rats with ligated ureters was found to depend on the length of time after establishment of obstruction. About 4% of plasma passing through the kidney was filtered after 30 min of total ligation, compared with nearly 20% in control rats. The rate progressively increased thereafter, exceeding half the control rate within 4 hr, but undergoing no further important changes up to 6 hr after ureteral obstruction. Intravenously administered inulin diminished rapidly in plasma of control rats, less rapidly in rats with ureters ligated 4 hr prior to the injection, and most slowly in nephrectomized rats, the relative concentrations 3 hr after injection being 1:3:8, respectively. Inulin recoveries were essentially complete in all cases. This supports the conclusion that concentration of inulin in plasma at termination of the experiments was inversely and solely related to efficiency of glomerular filtration. The apparent 3-hr inulin space for these special conditions, derived from measurements on nephrectomized rats, was 17.3 ml/100 g total body wt. in rats fasted for 24 hr with free access to water.

Swizzle sticks may be hazardous to one's health. Two extraordinary cases of swizzle sticks impaled in stomachs rather than in olives are described. In the first, the reaction was acute and promptly remedied by gastrotomy. In the second, the presentation was after protracted symptoms, and subtotal gastrectomy revealed chronic foreign body reaction previously thought to be neoplasm. This newly described source of gastric injury, although rare, must be considered in any patient who freely imbibes and presents with gastrointestinal symptoms, acute or chronic.