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Biomedical subjects

T Ericson

Publications and source records attributed to T Ericson.

At least 37 records · Page 2Linked to original sources

Effects of chronic stimulation of salivary gland beta-adrenoceptors on saliva composition and caries development in the rat.

The effects of long-term beta-adrenoceptor stimulation or inhibition on parotid and submandibular glands, saliva secretion, and caries development were studied. Groups of rats were treated daily with: 0.5 or 5 mg/kg body weight of isoproterenol (IPR), 0.5 or 5 mg/kg bw propranolol (PRO), or saline. After 42 days, saliva was collected and analyzed for secretion rate, total protein, amylase, sialic acid and electrolytes. Total protein and amylase in saliva decreased and potassium increased in the high IPR group. Phosphate increased in both IPR groups and decreased in the high PRO group. The average weight of parotid glands increased 3.7 times in the high IPR group and 1.8 times in the low IPR group. Amylase and total protein in parotid gland extracts decreased in both IPR groups. The submandibular gland weight increased 1.5 times in the high IPR group. Total protein decreased in the high IPR group. There was no difference in caries development.

Amylases↗

Effect of a moderate vitamin A deficiency on saliva secretion rate and some salivary glycoproteins in adult rat.

The study presents the effect of a low vitamin A intake on saliva secretion rate and some salivary glycoproteins in the adult rat. Sixteen rats in the experimental group were fed a vitamin A deficient diet (0.11 micrograms retinol/g diet) and 14 rats in the control group a diet with adequate content of vitamin A (4.74 micrograms/g diet). At the end of the experimental period of 10 wk, whole saliva, blood, and liver samples were collected. No difference in the serum content of retinol was seen between the two groups. The liver values were significantly lower for the rats in the experimental group compared to the values in the control group. No difference was seen between the two groups in saliva secretion rate, salivary peroxidase activity, or the concentrations of total protein and markers for total glycoprotein secretion. However, the activity of a bacteria agglutinating glycoprotein, BAGP, was significantly reduced in the rats fed the vitamin A deficient diet.

Animals↗

Effects of a 900-kcal liquid or solid diet on saliva flow rate and composition in female subjects.

Eleven healthy females of normal weight participated in a study on the effects of two 900-kcal (5,548 kJ) diets, one solid and one liquid, given for 8-day periods. Unstimulated and stimulated whole saliva was collected before, during, between, and after the two different experimental periods. The dietary intake was recorded and evaluated for its content of energy and nutrients during normal and experimental periods. The 900-kcal liquid diet caused a reduction in saliva secretion rate, sialic acid, and phosphate concentrations and an increase in the sodium concentration as well as in the ratio of total protein to sialic acid. Chewing a 900-kcal solid diet restored saliva secretion and composition. The rate of dental plaque formation was increased by both 900-kcal diets, but more during the liquid period.

Adult↗

Effect of long-term isoproterenol treatment on caries development in the rat using a low-cariogenic model.

Forty-eight Sprague-Dawley rats were divided into four groups. Two groups were injected daily with saline (groups 1 and 2) and two groups with isoproterenol (0.5 mg/kg body weight, groups 3 and 4) beginning at the age of 21 days. Groups 1 and 3 were each day fed nine subsequent sucrose-containing meals followed by eight starch-containing meals. Groups 2 and 4 were fed alternating sugar- or starch-containing meals, totally 17 meals per day. The animals were sacrificed after 14 weeks. At the end of the experiment, the animals in the isoproterenol groups had higher body weights. Caries development increased significantly after isoproterenol treatment. The diet regimen with alternating sugar- or starch-containing meals increased caries development, particularly in combination with isoproterenol treatment. Using low cariogenic conditions, we found that an unspecific beta-agonist (isoproterenol), given posteruptively at a low dose, enhances caries development.

Animals↗

Saliva concentrations of some selected proteins and glycoprotein markers in man after supplementary intake of beta-carotene.

Vitamin A has profound effects on cell biology, morphology and function of excretory cells. In the present study we investigated the effect of supplementation with beta-carotene (provitamin A) on the secretion of salivary glycoproteins and some antibacterial components. Eighty-nine men, drawn from a larger double-blind pilot study among Finnish men of a high socio-economic standard, participated in this study which lasted for 60 days. The men were allocated either to beta-carotene supplementation of 20 mg a day or to placebo treatment. At the end of the study samples of stimulated whole and parotid saliva were collected and examined for total protein as well as hexosamine, sialic acid, thiocyanate and the activity of salivary peroxidase. The secretion rate of whole saliva was calculated and the activities of lysozyme, a bacteria aggregating glycoprotein (BAGP) and secretory IgA were measured in parotid saliva. Significantly higher levels of beta-carotene, but not retinol, were found in serum and whole saliva in the beta-carotene group compared to the placebo group. Retinol or beta-carotene could not be detected in parotid saliva. No difference was found either in saliva secretion rate or in the composition of whole or parotid saliva between the beta-carotene and the placebo group.

Adult↗

Saliva composition and caries development during protein deficiency and beta-receptor stimulation or inhibition.

We tested the hypothesis that a low protein diet (5%) would change the conditions for synthesis and release of protein from the salivary secretory cells and increase caries development. In addition, we tested whether the simultaneous use of a beta-adrenoceptor agonist or antagonist had an additive effect. After an experimental period of nine weeks the animals fed the 5% protein diet had lower body weights, saliva secretion rates and total protein secreted per minute than a control group fed a 20% protein diet. There were greater numbers of cariogenic streptococci on the teeth and the caries scores were higher in the rats fed the low protein diet than in the rats in the control group. The beta-receptor agonist, isoproterenol, given to rats fed the 20% protein diet, caused a reduction in protein concentration and amylase activity in saliva and a slight increase in caries development. Propranolol had no effect on either saliva composition or caries development.

Animals↗

Interactions between peroxide and salivary glycoprotein: protection by peroxidase.

The effect of ascorbic acid oxidation and of peroxide on salivary glycoproteins has been studied. No signs of depolymerization of the glycoproteins were observed as a result of treatment of whole saliva or the isolated glycoprotein fraction from human saliva with an ascorbic acid, hydrogen peroxide and cupric ion combination. Sialic acid was analyzed with two methods which gave different chromogens of the acid. The conclusion could be drawn from the results that the effect of ascorbic acid oxidation was a decarboxylation of sialic acid in salivary glycoproteins. This also destroys the bacteria-agglutinating activity of saliva. Full protection of the agglutinin activity is given by salivary peroxidase. It is suggested that one role of peroxidases in saliva is to protect biologically active proteins from the action of oxygen or its radicals.

Ascorbic Acid↗

Effect of beta 2-adrenoceptor agonists on saliva proteins and dental caries in asthmatic children.

Twenty-four children, from 10 to 20 years old, with asthma treated with beta 2-adrenoceptor agonists were matched with healthy controls of the same age, sex, and social background. Stimulated whole and parotid saliva was collected, and decayed and filled tooth surfaces as well as oral hygiene habits were recorded. The dietary and sugar intake was carefully checked by a four-day dietary record. The asthmatic children had a 26% lower (p less than 0.05) value for secretion rate of whole saliva. Seventy percent of the children with Streptococcus mutans counts greater than 2 X 10(5) colony-forming units/mL of whole saliva belonged to the asthmatic group (p less than 0.05). The concentrations of total protein and amylase in parotid saliva were significantly lower for the asthmatic children. The concentrations of potassium, salivary peroxidase, bacteria-aggregating glycoproteins, and secretory IgA were not affected, but the secretion rate of parotid saliva was 36% lower in the asthma group (p less than 0.05). Oral hygiene and dietary habits did not differ between the groups. The asthmatic children had higher DFS scores, but these were not significantly different from those of the healthy controls (p = 0.07). We suggest that subjects with asthma treated with beta 2-receptor agonists should receive special prophylactic attention.

Adolescent↗

Ribonuclease in different types of saliva from cystic fibrosis patients.

The flow rate, the activity of ribonuclease (RNAase) and the concentration of protein were determined in whole saliva and in parotid and submandibular saliva from patients with cystic fibrosis (CF) and from healthy controls, both before and after stimulation of the salivary secretion. Lower flow rates were found in all types of saliva from CF-patients than in control saliva. Increased activity of RNAase was found in CF saliva, both before and after stimulation of the secretion. The concentration of protein was also increased, but to a lesser degree. No correlation was found between either RNAase activity or protein concentration and severity of the disease or age of the children. It is therefore unlikely that these disturbances are secondary to progression of the disease. Considerable variations in RNAase activity and protein concentration were observed, especially within the CF group, and therefore despite the significant increase in these variables in CF their estimation is of limited diagnostic value.

Adolescent↗

The effect of malnutrition on caries development and saliva composition in the rat.

The purpose of this study was to investigate the effect in rats of malnutrition on caries development and on some antibacterial substances in saliva. By gastric intubation, two groups of ten rats each were fed a liquid basic diet (100% diet), and two similar groups were fed the basic diet diluted with an equal volume of water to contain 50% of the nutrients of the basic diet (50% diet). One group on undiluted and one group on the diluted basic diet were offered sucrose as a supplement by mouth 17 times daily, using a programmed feeding machine, and the other two groups were offered starch in a similar manner. The extent and depth of the caries lesions were five times greater in the low-nourished (50% diet) sucrose group in comparison with the group given the undiluted diet supplemented with sucrose. The 50% diet group ate more frequently from the offered supplement. The 50% diet induced lower salivary lactoperoxidase activities, and there was an additive effect of starch as supplement. Higher concentrations of sIgA were found in the saliva of animals fed the 50% diet supplemented with sucrose than in those fed sucrose and the 100% diet. Significantly greater levels of sIgA and IgG were found in the saliva from the 50% diet-sucrose group than in the 50% diet-starch group. Plaque scores differed slightly but not significantly between the groups. The starch group receiving 100% diet showed a slightly lower level of S. mutans infection as compared with the 50% diet-starch group; the caries scores in the starch groups did not differ.

Animals↗

Studies of the effect of diet on saliva secretion and caries development: the effect of fasting on saliva composition of female subjects.

In the present investigation 11 females of normal constitution were subjected to a standardized fasting diet for 8 days. Three subjects dropped out early during the experimental period. Saliva and blood samples were collected before, during and after the fasting period. Serum analyses were made of some parameters often studied during undernutrition. As expected, values for creatinine and uric acid were increased. Secretion rate, pH, buffer capacity, electrolytes, total protein, carbohydrates, some antibacterial substances, the amount of Streptococcus mutans, total streptococci, and lactobacilli were determined in the saliva samples. The rate of plaque formation was also estimated. The effect of fasting on the measured parameters varied greatly among the individuals. Fasting caused a significant decrease in secretion rate, concentration of phosphate and sialic acid in stimulated whole saliva. There was no significant increase in concentration of any substance measured. The decrease of the ratio of sialic acid to protein indicates a disturbance of glycoprotein synthesis. In resting saliva the activity of a bacteria-aggregating glycoprotein appeared to be unchanged, whereas the decreases in thiocyanate concentration and lysozyme activity were statistically significant. Lactoperoxidase activities did not change significantly. The amount of IgA, IgG, IgM as well as the microbial counts showed no changes. The rate of plaque formation increased during fasting.

Adult↗

Characterization of a salivary agglutinin reacting with a serotype c strain of Streptococcus mutans.

A protein, which can agglutinate a Streptococcus mutans serotype c strain, was isolated from parotid saliva by affinity adsorption of the salivary agglutinin to the microorganism followed by a desorption with a 10 mM phosphate buffer. The agglutinin was subjected to preparative ultracentrifugation, gel filtration, and ultrafiltration. The native purified agglutinin is active only in the presence of Ca. Polyacrylamide gel electrophoresis, analytical centrifugation, and analyses of amino acids and carbohydrates showed that the native agglutinin was a fucose-rich glycoprotein with a carbohydrate content of 45% and with a molecular weight of at least 5 X 10(6). After sodium dodecyl sulphate treatment the molecular weight was 4.4 X 10(5). There was a low content of proline and a high content of aspartic acid, serine and threonine. The concentration of agglutinin in parotid saliva is less than 0.5% of total protein. It has high biological activity: 0.1 microgram agglutinin causes a rapid aggregation of approximately 10(8) bacteria.

Agglutination Tests↗