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Biomedical subjects

B Krasse

Publications and source records attributed to B Krasse.

At least 55 records · Page 3Linked to original sources
PubMed1986

Oral glucose clearance in subjects with high or low salivary levels of Streptococcus mutans and lactobacilli.

The ability to eliminate sugar from the oral cavity was studied in subjects with high or low numbers of salivary Streptococcus mutans and lactobacilli. The glucose concentration in saliva was determined after consumption of biscuits using the Gloxtest, and the logarithms of the glucose values were plotted against time. The sugar clearance time was measured where the slope of the plot intersected with a glucose level of 1 mg/ml. Subjects with a high level of S. mutans had a significantly longer clearance time than subjects with a low level. More salivary lactobacilli were found in a subject group with a long sugar clearance time than in a group with a fast clearance rate.

Adolescent↗
PubMed1986

Comparison between a dip-slide test and plate count for determination of Streptococcus mutans infection.

A significant correlation was found between the results of a dip-slide test and a conventional agar-plate method for determination of the salivary Streptococcus mutants population. The growth density of S. mutans around bacitracin discs on the dip-slide was estimated and examination of the dip-slides with or without a microscope showed good agreement. The percentage of identical scores between two observers increased from 69 to 84% with the use of a microscope. Scores from dip-slides inoculated with saliva by means of a cotton swab showed good agreement with those obtained with stimulated saliva. The dip-slide method is simple and reliable and can be a valuable tool in general practice for the estimation of the S. mutans infection.

Bacteriological Techniques↗
PubMed1985

Support for and implications of the specific plaque hypothesis.

The role of specific microorganisms in dental caries is reviewed. A considerable amount of evidence supports the association between organisms of the Streptococcus mutans group and caries incidence and prevalence. The cariogenic potential of S. mutans is probably due to the unique combination of properties with which this microorganism is endowed. The pathogenic potential can be modified by changes in the environment. Lactobacilli play a major role in the development of a lesion. The specific plaque hypothesis has important implications because the association between S. mutans, lactobacilli and dental caries can be used in diagnosis, treatment and prevention of the disease in groups of subjects as well as in the individual case.

Animals↗
PubMed1985

The cariogenic potential of foods--a critical review of current methods.

Current methods used in examining the cariogenic potential of foods are plaque pH measurements, measurements of adhesiveness of foods, experimental caries models and animal tests. pH measurements can be used for separating the non-acidogenic foods from the acidogenic ones but they are not suitable for separating foods with different levels of caries inducing potential. This is illustrated by the fact that virtually all foods which contain carbohydrates cause the pH of human plaque to fall below 5.5. Cooked rice and beans also give such a pH drop but these foods have a very low caries-inducing potential, as shown in studies of persons with hereditary fructose intolerance. Furthermore, experimentation has shown that acid formation and enamel dissolution are not directly correlated. Animal models exist in which various test foods can be examined under identical conditions. By using the same microbial challenge and a reference food, for example sucrose, the relative cariogenic potential of a test food can be calculated. One limitation with these animal models is that the foods have to be given in powdered form and not in the physical form in which they are consumed by humans. The main objection against most of the current methods is that they reflect important factors in our concept of the pathogenesis of dental caries only to a limited extent. For example, only the animal tests can be used to illustrate the extent to which foods support the colonization of S. mutans on teeth. The qualitative composition of the plaque is practically never considered. A series of tests can, however, be combined to give more relevant information about the caries-inducing potential of foods.(ABSTRACT TRUNCATED AT 250 WORDS)

Acids↗
PubMed1984

Biochemical and immunological differences between hydrophobic and hydrophilic strains of Streptococcus mutans.

Hydrophobic strains of Streptococcus mutans were compared with paired variants showing reduced hydrophobicity. Extracts of hydrophobic cells contained a number of high-molecular-weight proteins which were not present on cells with decreased hydrophobicity. The proteins were found in purified cell walls, suggesting that they are located on the bacterial surface. Trypsin treatment of whole cells destroyed the proteins and reduced the hydrophobicity. Chemical analysis did not reveal any marked differences in the proportion of cell wall constituents. The amino acid compositions and lipoteichoic acid contents of hydrophobic and hydrophilic cell walls were similar. Culture supernatants from the hydrophilic variants contained high-molecular-weight proteins similar to those extracted from the cell walls of the hydrophobic parent strains, indicating that the variants were impaired in their ability to incorporate the hydrophobicity-associated proteins into the cell wall. The dominant protein had a molecular weight of 190,000, similar to that of antigen I/II (B) of S. mutans.

Alkanes↗
PubMed1983

Preventive measures in mothers influence the establishment of the bacterium Streptococcus mutans in their infants.

First-time mothers who had a high salivary number of Strep. mutans [greater than or equal to 10(6) colony-forming-units (c.f.u.) per ml] were selected. Every second mother was given a special preventive programme to reduce her salivary level below 3 x 10(5) c.f.u. per ml. Where a reduction of Strep. mutans was achieved in the mother, the establishment of Strep. mutans in her infant was prevented or delayed. Thus, 28 mothers were successfully treated until their infants were 23 months old and only 3 of their infants (11 per cent) were infected with Strep. mutans, compared with 17 out of 38 infants in the control group (45 per cent). In both groups, the percentage of infected infants increased with increasing age, although at all ages fewer infants were infected with Strep. mutans in the test group than in the control group. Sixteen infants of successfully treated mothers had reached the age of 36 months. Three were infected (19 per cent) compared with 17 out of 27 in the control group (63 per cent). These findings show that the spread of Strep. mutans can be delayed or prevented by measures directed against the main source of infection, an approach which is successful in the prevention of other infectious diseases.

Adult↗
PubMed1983

Dental health education by "barefoot doctors".

In an insurance company 18 out of 507 employees were trained as dental health educators. They then informed their fellow workers about prevention of caries and periodontal disease in groups of about 10 persons. Two information meetings were held during a period of 10 months. Eighty-nine percent of the employees were positive to this educational programme. Twenty-two percent said that they had reduced the intake of sucrose after the first meeting. Even more persons reduced their sucrose intake later. Saliva secretion rate and buffer capacity were analyzed and the number of lactobacilli and Streptococcus mutans were determined before and after the information meetings. A significant reduction in the number of lactobacilli was found, confirming the change in carbohydrate intake. The information raised the level of knowledge about dental health among the employees. It was suggested that this type of educational programme should be used in other health areas.

Adult↗
PubMed1983

Salivary immunoglobulin A antibodies and recovery from challenge of Streptococcus mutans after oral administration of Streptococcus mutans vaccine in humans.

Heat-killed Streptococcus mutans was administered orally in two periods of 1 week to six subjects in an attempt to affect the salivary immunoglobulin A (IgA) response to this bacterium. Enzyme-linked immunosorbent assays were used to detect specific IgA antibody activity, and an immunofluorescent assay was used for measurement of total IgA in parotid saliva. The salivary IgA response to S. mutans was compared with that against a noncross-reacting antigen preparation from Escherichia coli and with antibody responses in five sham-immunized subjects. No change in salivary IgA response to S. mutans was observed after oral administration of this organism. Significantly less streptomycin-resistant S. mutans could be recovered from the six test subjects than from the five controls after the first of two challenges with streptomycin-resistant microorganisms. At the day of the first challenge, a significantly higher IgA antibody response to all tested antigens was observed in the test group than in the control group. The data show that this difference was not related to the oral administration of S. mutans but rather was an occasional finding. The coincidence of a rapid elimination of the challenge strain and a high IgA antibody response to S. mutans supports the concept that salivary IgA antibodies could have a biological significance in the human defense against cariogenic microorganisms.

Administration, Oral↗
PubMed1983

Correlation of level and duration of Streptococcus mutans infection with incidence of dental caries.

The caries incidence at various levels of Streptococcus mutans infection was analyzed in a control group and a test group. In the control group, the incidence of caries and the duration of S. mutans infection were significantly correlated. In the test group, the S. mutans infection was suppressed by antimicrobial measures when the number of S. mutans exceeded 250 X 10(3) CFU per ml of saliva. The results illustrate that the level and duration of the S. mutans infection are strongly correlated to the incidence of caries. The findings support the concept of S. mutans as a key cariogenic microorganism and illustrate the value of antimicrobial treatment in the prevention of caries.

Adolescent↗
PubMed1983

Available immunoglobulin A antibodies in mouth rinses and implantation of Streptococcus mutans.

Immunoglobulin A (IgA) antibodies reacting with Streptococcus mutans were analyzed in mouth rinses from 38 adults. Antibody activity was determined by an enzyme-linked immunosorbent assay. The IgA antibody activity varied considerably in samples from different individuals. Of the 38 subjects, 12 volunteered in an implantation experiment and were challenged with streptomycin-resistant S. mutans. The results indicated that individuals with relatively high IgA antibody activity in mouth rinses more rapidly eliminated the challenge strain than subjects with low IgA antibody activity.

Adult↗
PubMed1982

Effect of caries preventive measures in children highly infected with the bacterium Streptococcus mutans.

The number of Strep. mutans in saliva samples was examined in 101 13-14-year-old children, 53 in a control and 48 in the test group. All in the test group with 2.5 X 10(5) Strep. mutans per ml saliva were treated with 1 per cent chlorhexidine gel, once a day, for 14 days when the number of Strep. mutans was greatly reduced. Saliva samples were then examined in the test group every 4th month and all children with Strep. mutans levels above 2.5 X 10(5) were treated. A few selected children had fissure sealants applied to the occlusal surfaces. After 3 years, the mean number of new carious lesions was 9.6 in the control group and 4.2 in the test group. In the children with 10(6) Strep. mutans at the start of the study, the corresponding figures were 20.8 compared with 3.9. Thus a reduction in caries activity can be achieved by controlled antimicrobial treatment.

Adolescent↗
PubMed1982

Streptococcus mutans, lactobacilli and dental health in 13-14-year-old Swedish children.

The dental health and the prevalence of Streptococcus mutans and lactobacilli were examined in 101 13-114-year-old children. The average number of decayed (incipient caries) and filled surfaces (DFS) was 10.1 and 12.8, respectively. S. mutans was not detected in 11% of the children while 21% had 10(6) or more S. mutans per ml saliva. Lactobacilli were not found in 21% of the children whereas 11% had 10(5) or more lactobacilli per ml saliva. Statistically significant correlations were found between S. mutans and lactobacilli, S. mutans and DFS, lactobacilli and DFS and S. mutans plus lactobacilli and DFS. Increasing numbers of S. mutans and lactobacilli, alone and in combination, were associated with an increased caries frequency.

Adolescent↗
PubMed1982

Interference of Salivary immunoglobulin A antibodies and other salivary fractions with adherence of Streptococcus mutans to hydroxyapatite.

The adherence of Streptococcus mutans to hydroxyapatite was studied in the presence of salivary fractions with varying activity of naturally occurring immunoglobulin A (IgA) antibodies. Human parotid saliva from different donors was fractionated by chromatography and compared. Salivary IgA antibodies had no decisive effect on the adherence of the S. mutans strain used. High-molecular-weight salivary components from some subjects had an adherence-promoting effect, whereas fractions collected after the void volume of a Sepharose 2B column always inhibited adherence. The data indicate that the influence of unfractionated saliva on adherence is dependent on the net effect of adherence-promoting and adherence-inhibiting components. This principle has to be considered when the effect of human saliva on microbial adherence is studied.

Adhesiveness↗
PubMed1982

Oral effect of other carbohydrates.

Historical data, epidemiological surveys, laboratory and animal experiments, clinical studies and observations in ordinary dental practice all illustrate that starchy fibrous foods have a low cariogenic potential. The recommended substitution of sucrose in Western diets by starchy foods would lead to a reduction of caries provided that these other carbohydrates replace the between meal consumption of sugar-rich products. The low cariogenic potential of a diet containing carbohydrates with a fibrous character is probably not solely due to its low sucrose content. Such a diet promotes mastication and saliva secretion which tend to reduce the caries risk. Furthermore, unrefined foods may contain caries-protective substances like phytates, trace elements and antibacterial factors. Lectins, which are found in many plants could be of importance by influencing the attachment of micro-organisms to the teeth in a favourable manner. The tradition to end a meal with fruit may thus have other oral effects than hitherto considered. In addition, a diet containing carbohydrates with a fibrous character and a low amount of sucrose probably has a low pathogenic potential for the periodontal tissues. However, no epidemiological data are available to support this assumption.

Animals↗