William A. Gibson

Intravenous Ascorbic Acid Loading in Subjects Classified as to Periodontal Status

Ascorbic acid is known to be indispensable for man and for certain other species that are also unable to synthesize this compound. While the exact role of ascorbic acid in metabolism is not understood, deficiency pronounced enough to produce scurvy leads to a characteristic symptom complex. Involvement of the soft tissues of the mouth, particularly a tendency to gingival enlargement and hemorrhage, is so consistently encountered that it is a prominent factor in the differential diagnosis of the truly scorbutic patient. A great deal of controversy exists in the literature, however, concerning the relationship between periodontal disorders and ascorbic acid deficiency.1-20 The present study was designed to determine whether or not blood and urine ascorbic acid levels, either before or after ascorbic acid injection, were significantly related to oral health status. Of further interest was the nature of the disappearance of excess blood ascorbic acid following intravenous dosage.

DEMONSTRATION OF 5'-NUCLEOTIDASE ACTIVITY IN DECALCIFIED BONES AND TEETH

The development of methods for the demineralization of houses amid teeth preserving sufficient emszyrne activity to permit. effective histochemical localization (Babogh, J. Histochem. Cytochem. 10. 232. 1962; amid Fuullmer and Limsk, Stain Techn. 39: 387. 1964) makes possible investigations into the emszynie activities of imsdividumab cells located in mimueralized amid cons tigusous tissumes. 5’-Nuucleotidase has been demomistrated to occur in the chomidrocytes of the oumter layers of the articumlar sumrface of fresh cut cartilage (Otte, P. Hoppe-Seyl. Z. 310.103. 1958). The present study of 5’-muucleotidase was carried oust on demineralized sectiomis. The mamsdibbes amid heads of fentumrs were taken front freshly sacrificed 100-150 g rats amid the tinfixed tissumes demineralized for 4 days in a neutral bumifered soluution of EDTA according to the method of Fumlbmer and Limuk with the addition of polyvimsylpyrrohidone (PVP) to niake a 7.5% solutionu. After demineralizatioii, specimens were frozemu on a block of carbon dioxide ice, attached to a chumck and sectioned in a cryostat at 8 M. Sections were picked up out cleami dry slides and allowed to dry for a few mimsutes at room temperature. After fixation for 10 mitt mi cold (4#{176}C) 10% mseut.ral formalimi, the sectiomts were incuibated at 37#{176}C for varying lengths of time in media at pH 7.2 prepared accordinug to the method of Wachstein and Meisel (Am. J. Clin. Path. 27: 13. 1957) using sodmum-g1ycerophosphate (Na53GP), adenosine triphosphate (ATP), adenosine momsophosphate (AMP), cytidine monophosphate (CMP), guanosine momiophosphate (GMP) and uuridine monophosphate (UMP) as suibstrates. Ims addition, pobyvimsylpyrrolidone (PVP) was added (1.9 g/50 ml) to minimize diffusion. Iuscumbationu periods of 15-30 mimi were foumnd to be adequmate for the demomustration of both ATPase amid 5’-numcleotidase activities. Nomispecific phosphatase activity unsing Na5GP as the suubstrate was slight ims sectionss imicubated for similar periods of time and was reduced by formalin fixation and the addition of cysteine (2.5 X 10 M). Such nonspecific phosphatase activity demonstrable at pH 7.2 has been ascribed by Novikoff as dume to the residual activities of alkaline and acid phosphatases (J. Histochein. Cytochem. 6: 251 . 1958). However, no attempt was made in the preseist study to resolve this question. Neither ATPase nor 5’numcleotidase activities appeared to be affected to amsy great extent by formalin fixation or by the addition of cysteine. The distributional patterns of ATPase amid 5’numcleotidase activities appeared to contrast sharply. While ATPase activity was for the most part confined to the walls of blood vessels, 5’nucleotidase activity was strongest in osteocytes, cememstocytes, chondrocytes and odontobbastic processes. In the epiphyseal disc, chondrocytes of the resting zone were heavily stained while chondrocytes of the proliferating and maturing zones were distinctly, but less heavily stained (Fig. 1). In agreement with Otte’s results, chondrocytes in the outer layers of the articular cartilage were stained (Fig. 2). Staining of osteocytes appeared to be rather uniform and uiot to differ with the maturity of the cells (Fig. 3). Staimiing of cementocytes, in general, was similar to that of osteocytes. Osteoblasts, cementoblasts, osteoclasts and fibroblasts showed little or no staining while the cell bodies of odontoblasts were moderately stained. Staining of the odontoblastic processes was not uniform. In many areas both the proximal and distal portiomus of the processes were rather heavily stained while the middle portions exhibited considerable variability (Fig. 4). When different 5’-nucleotides were uised as suibstrates mso differences were noted in the localization of 5’-miucleotidase activity. Slight differences, however, were noted in the intensity of staining approximately in the following order of descendimsg activity: IJMP > AMP > GMP > CMP. The metabolic significance of these results awaits further clarification. However, the results would seem to add to the increasing evidence that these cells are metabolically more active thami hitherto suspected. August 4, 1966 WILLIAM GIBsoN

Inorganic Phosphate Concentration in Body Fluids as Related to Dental Caries Status

While it is generally agreed that dietary phosphate supplements reduce the incidence of caries in laboratory animals, there is disagreement as to the actual relationship of the phosphate concentration in body fluids to caries activity in man. The present study of this relationship sought answers to the following questions: (1) Is there a significant relationship between the phosphate concentration of blood serum or parotid fluid and dental caries experience? (2) Is parotid fluid flow rate related to caries status?

AN IMMUNOFLUORESCENT TECHNIQUE FOR OBSERVING THE BINDING OF CONCANAVALIN A TO FROZEN TISSUE SECTIONS

An indirect fluorescent antibody technique has been developed to observe the binding locus of concanavalin A (CON A) to specific structures in frozen tissue sections. The technique was developed using frontal sections of the embryonic rat head with particular attention focused on the secondary palate. The binding of CON A appeared to be mainly extracellular with the most intense fluorescence observed in basement lamina and cartilaginous structures. CON A binding was highly specific in that it was eliminated in the presence of competing sugars such as α-methyl mannoside. This relatively quick and simple technique should allow the observation of developmental or pathologic changes in CON A binding to frozen tissue sections from a variety of sources.

Serum total protein, albumin, and globulin in relation to periodontal status and caries experience☆

Abstract Correlations were sought between oral health status and serum total protein, albumin, and globulin levels for 515 systemically healthy young men. No highly significant correlations were found between either DMFS or periodontal status and any of the serum components under study.