Robert E. Stone

In vitro studies of the chromogenic reactions between selected carbohydrate derivatives and the amino acids common to human enamel and dentine

Abstract The chromogenicity of amino acid-carbohydrate derivative combinations has been investigated in an effort to further localize the source of the yellow-brown pigmentation of human dental caries. Colour development was studied in test systems comprised of the eighteen amino acids common to human enamel and dentine and four fermentation or decomposition products of carbohydrates. Each of the eighteen amino acids entered into chromogenic reactions with glyceric aldehyde, dihydroxyacetone, furfural and/or 5-hydroxymethylfurfural in degrees which varied with the pH, time, temperature and/or concentration of the reactants. With but few exceptions the pigments resulting from the interaction of the amino acids and carbohydrate derivatives had properties consistent with melanoidins, the pigment complexes which have been isolated from human carious teeth.

Effect of 2-Acetylamino-1,3,4-Thiadiazole-5-Sulfonamide (Diamox) on Sodium, Potassium, Bicarbonate and Buffer Content of Saliva.

Summary and Conclusions 1. Daily administration of 2-acetylamino-l, 3, 4-thiadiazole-5-sulfonamide provokes a pronounced decrease in sodium, bicarbonate and buffer content of paraffin-stimulated human saliva in both normotensive and hypertensive patients. Potassium level of saliva was not affected. 2. Changes in saliva sodium, potassium, bicarbonate and buffer content which followed administration of carbonic anhydrase inhibitor were similar to those observed in normotensive persons in whom metabolic acidosis was induced with ammonium chloride.

Human Nutritive and Growth Failure

The unrelenting need for life-giving chemicals places the child at the mercy of his diet and of his capacity to provide his tissues with the constituents thereof. Digestion, absorption, assimilation, detoxication and excretion each contribute to this end and may be disrupted by the cellular degeneration that follows deficiency-induced metabolic failure. Such failure, whether latent or overt, is nutritionally correctable provided the damage is reparable and the treatment is knowledgeable.

Comparison of Glutamic-Oxalacetic and Glutamic-Pyruvic Transaminase Concentrations in Human Saliva and Serum.

Summary and conclusions Detectable quantities of GOT and GPT were found in 100% and in 89% respectively of samples of stimulated saliva from 81 patients. The saliva GOT content exceeded saliva GPT level in 91% of cases. Incubation of an aliquot of each saliva sample with glucose resulted in a pronounced increase in GPT and diminution in GOT. Comparison of saliva transaminase levels with those of concurrently collected samples of serum showed no significant correlation, thus signifying that the prime and immediate source of saliva transaminase is oral rather than systemic.

Hypotension associated with nutritive failure.

Summary and Conclusions Following the administration of desoxycorticosterone acetate to persons with nutritive failure and hypotension, there was a prompt increase in blood pressure readings and in body weight (the increase in body weight is associated with retention of sodium in the tissues and this problem is being studied further). When the administration of this substance was discontinued, the blood pressure readings promptly returned to normal. During the first week after the administration of desoxycorticosterone acetate was begun, one patient stated that she had great symptomatic improvement; one complained of severe headaches, and she developed a “moon-faced” appearance which gradually disappeared when the injections were discontinued; the third patient noticed only swelling of the ankles. While our findings are of general interest, we do not recommend the use of desoxycorticosterone acetate as a therapeutic agent for hypertension.

Human Tooth Structure as a Bacterial Culture Medium

Whereas the microbial growth-promoting properties of human saliva have been the subject of numerous investigations (N. B. WILLIAMS, D. Pract., 3:265, 1953), little is known of the bacterial growth-supporting capacity of human tooth structure. The following in vitro studies were undertaken to obtain such information. Eight samples of paraffin-stimulated whole saliva and 8 carious teeth served as the source of the test organisms. The carious teeth had been thoroughly cleaned of extraneous matter after extraction and stored in empty screw-capped jars at 6° C. for more than 5 years. Primary cultures from each saliva sample and carious tooth were grown in 10 ml. of thioglycolate broth incubated at 37° C. for 24 hours. Inoculums were prepared from the 24-hour cultures by washing the organisms in physiologic saline solution as previously described (S. DREIZEN and T. D. SPIES, J. dent. Res., 26:409, 1947). One drop of each inoculum was seeded into duplicate tubes containing 100 mg. of ground tooth structure and 5 ml. water, the suspension having been autoclaved prior to use. The ground tooth material was obtained by pulverizing 15 cleaned, caries-free human teeth in a laboratory mill* fitted with a 2-mm.-mesh sieve. The powder was pooled and mixed before weighing and dispensing. One set of inoculated tubes containing powdered tooth was incubated at room temperature, the other at 370 C. After 24 hours, one loopful from each powder-containing tube was placed in 10 ml. of thioglycolate broth. The organisms recovered after incubation in this medium were then identified by conventional bacteriologic methods. They were cultivated in pure culture and reseeded into tubes containing powdered tooth and water in the aforementioned manner. Every 24 hours, single loop aliquots from each tube were returned to fresh thioglycolate broth. This procedure was continued until growth in thioglycolate medium could no longer be detected turbidimetrically. Each of the eight samples of whole saliva yielded an organism that tolerated the dispersion of tooth structure in water. Specifically, these included five