Alfred H. Free

The Citrate Content of Whole Teeth, Dentin and Enamel

For a long time it has been appreciated that citrate is a constituent of milk and urine. With the development of more accurate and specific methods (1, 2) for the determination of citrate, this ion has been recognized as a constituent of many tissues and body fluids. The occurrence of citrate in the animal body has been reviewed by Smith and Orten (3). Scherst6n (4) has shown that there is quite a large amount of citrate in semen and in the secretion of the seminal vesicles, the concentration in semen being as high as 410 mg. per 100 cc. and in the secretion of the seminal vesicles as much as 633 mg. per 100 gm. which is comparable to the amounts of citrate found in milk and in alkaline urine. These observations have been extended by Huggins and Neal (5) who found in 9 samples of human prostatic fluid, citrate concentrations ranging from 480 to 2688 mg. per 100 cc. Dickens (6) discovered that bone contains a very large amount of citrate, the concentration ranging from 272 mg. per 100 gm. up to as high as 1660 mg. per 100 gm. in dried powdered bone. This investigator isolated both the pentabromoacetone derivative of citric acid and pure citric acid from bone meal. The present report describes studies made of the occurrence of citrate in whole teeth and in separated enamel and dentin.

A simplified urine and serum screening test for salicylate intoxication

The extremely high incidence of salicylate intoxication makes it desirable to have a screening test available. Such a procedure should be simple and rapid enough to be used routinely on all admission and emergency cases since salicylate intoxication may not be suspected. This report describes studies with a stick test used on urine and serum. Test results agree well with quantitative measurements. Specimens tested included urine and serum from dogs and human beings after experimental administration of aspirin as well as samples from cases of salicylate intoxication or high therapeutic salicylate levels. The test strip develops an immediate brownish purple color with as little as 20 mg. per cent free salicylate. Data are presented to show that reliable results are obtained with the test even by inexperienced individuals.

Non-Identity of Gray Hair Produced by Mineral Deficiency and Vitamin Deficiency.

The recent recognition of a specific organic food factor 1 2 necessary for the maintenance of the black fur of black or piebald rats has raised the question as to whether the phenomenon of graying noted by older workers 3 4 5 6 particularly in rats on an exclusive milk diet is due to this cause or is due to a specific mineral deficiency. Jukes and Richardson 7 have pointed out that milk is not a good source of filtrate fraction vitamins. The black fur of young piebald rats fed an exclusive diet of either powdered whole milk or of fresh certified milk rapidly and uniformly became gray. Addition of a supplement of 0.25 mg of iron, 0.05 mg of copper and 0.05 mg of manganese cured the grayness if it had developed or prevented any change in the color of the fur of rats which were fed milk with the above mineral supplements from the time of weaning. Attempts to ascertain which of the 3 metals is responsible have not at present yielded entirely conclusive results. Rats developing a nutritional anemia show a marked diminution of appetite and the possibility exists that the graying of rats may be due to a diminished intake of vitamin accompanying the reduced intake of the vitamin-poor milk. This has been disproven since in 2 groups of rats fed isocaloric amounts of milk, those supplemented with iron, copper and manganese did not develop grayness whereas those fed milk alone became quite gray. It has also been found that rats that have developed grayness will become black when supplement-ed with the above minerals whereas the isocaloric controls without minerals remain gray. Rats, following the production of gray hair by a milk diet, when supplemented with a rice bran extract∗ rich in the factors of the B complex very slowly regained their black color. However, control rats fed equal quantities of the ashed rice bran extract likewise slowly became black.

The absorption of galactose from the gastro-intestinal tract in deficiency diseases

Galactose absorption studies have been made on normal subjects and on patients with deficiency diseases. In studying the method it was found that the amount of galactose ingested had a marked effect on the level of galactose attained in the blood. Therefore, in such a test the amount of galactose employed should be calculated on the basis of body weight. All of the patients with active pellagra and nontropical sprue showed evidence of impaired absorption. Improvement in absorption accompanied clinical improvement in pellagra but not in sprue. Two of four cases of rosacea keratitis which responded to riboflavin therapy gave indication of decreased absorption which improved when the signs of rosacea keratitis disappeared. Approximately one-half of the patients with pernicious anemia showed impaired absorption. Changes in absorption noted in these patients did not parallel the changes in the red cell counts and the hemoglobin levels. This suggests that a secondary factor is involved in absorptive changes noted in patients with pernicious anemia.

Variations in the enzymatic activity of duodenal contents. Preliminary report.

A system of enzyme analysis has been developed which permits an accurate estimation of the proteolytic, lipolytic and amylolytic activity of the enzymes of duodenal contents. When this system of analysis is applied to duodenal contents secured after stimulating pancreatic secretion with olive oil, it has been found possible to define the normal range of values with a reasonable degree of accuracy, and give these in terms of the normal taken as 100. Employing this method of recording the enzyme activities to pathological cases, abnormal values stand out very clearly from the normal. Very low values are found in pancreatitis and certain other conditions, while subnormal values are encountered in various gastro-intestinal disorders which may have an effect on the pancreas. In diabetes the enzyme activity may be subnormal, or considerably elevated.

Availability of iron in wheat.

Elvehjem, Hart, and Sherman 1 have reported that the inorganic iron content of wheat is approximately 47% of the total iron content. Their biological studies indicated that this figure also represents the available iron content. On the contrary Rose, Vahlteich, and MacLeod 2 observed that wheat is an excellent source of iron for hemoglobin formation. In order to determine whether there is any great variation in the form of iron in different varieties of wheat, 11 samples representing both hard spring wheat and soft winter wheat were analyzed for total and inorganic iron. A modification of the technic of Elvehjem, Hart, and Sherman, 1 which employs a longer extraction period, was used to determine the inorganic iron, whereas the total iron was determined on ashed samples by the thioglycolic acid method. 3 The total iron of the 11 samples ranged from 2.90 mg. to 4.87 mg. of iron per 100 gm. of wheat. The inorganic iron showed about the same amount of variation, the range being from 2.46 mg. to 4.04 mg. of iron per 100 gm. of wheat. The percentage of inorganic iron with respect to the total iron varied from 73% to 88%, the average being 81%. This figure agrees fairly well with the value suggested by Shackleton and McCance. 4 Two of the samples of wheat were also used for a biological assay. Albino rats were made anemic by employing an exclusive milk diet. As soon as values below 4.0 gm. of hemoglobin per 100 cc. of blood were attained, the experimental diets were started. Three groups of experimental animals received 0.25 mg. of iron per day. One group of 5 animals received 0.25 mg. of iron per day furnished by FeCl3; a second group of 6 animals received Trumbull wheat (soft winter wheat) in quantities to supply the same amount of iron per day; and the third group of 6 animals received Nabob wheat (soft winter wheat) in quantities to supply 0.25 mg. of iron per day.

Urine Glucose Tests for Diabetic Patients with Impaired Vision

A colorimetric test procedure called Mega-Diastix is described for detection and measurement of glucose in urine. The test is designed for use by diabetic patients with impaired vision. Data establishing the performance capabilities of this rapid, convenient test are presented. As an internal standard, the recommended procedure utilizes effervescent control tablets for preparation of simulated urine. Also described is a touch fermentation test for detection of urinary glucose by totally blind patients. Data are given that demonstrate the accuracy and ease of performance of this test, which entails a rapid yeast fermentation. An internal standard is also incorporated into the procedure for this test.