bluuebunny/crossref_metadata_2025 huggingface dataset:
Generation and degradation of the complement fragment C5a in human serum by Bacteroides gingivalis
Authors: Sundqvist Göran , Bengtson Anders , Carlsson Jan
Published: December 2007

The ability of Bacteroides gingivalis to generate chemotactic activity and the complement fragment C5a in human serum was assayed. When fresh serum was incubated with B. gingivalis there was a rapid increase of chemotactic activity of the serum during the first 15 min, but longer incubation resulted in loss of chemotactic activity. When heat‐inactivated serum was incubated with B. gingivalis similar increase and decrease of the chemotactic activity of serum was also observed. The chemotactic peptide C5a could be demonstrated in all sera showing chemotactic activity. The generation of C5a and possibly also other chemotactic substances in heat‐inactivated serum by B. gingivalis may mean that this chemotactic activity was formed from serum proteins by the proteolytic activity of B. gingivalis. The proteolytic activity of B. gingivalis may also be responsible for the inactivation of C5a generated in serum.
Colonization of osseointegrated titanium implants in edentulous patients. Early results
Authors: Mombelli A. , Buser D. , Lang N. P.
Published: December 2007

The purpose of this investigation was to study the colonization of newly set implants in edentates and to monitor the development of the predominant subgingival microbiota during the first 6 months of wearing the implants in vivo. Microbial samples of the receiving sites were taken one day prior to the insertion with sterile cotton pellets. After implantation, one site per implant was sampled with sterile paperpoints once every week for 2 months, and thereafter in monthly intervals up to 180 days. A total of 114 samples of 9 sites from 5 patients were evaluated using the darkfield microscope and cultured anaerobically on non‐selective and selective media. Representative colonies were identified by atmospheric growth capabilities, Gram‐staining characteristics and biochemical tests. Small amounts of bacteria were collected from the preoperative swabs. On an average 86% of the microorganisms were identified morphologically as coccoid cells and over 80% of the cultivated bacteria were Gram‐positive facultative cocci. After implantation, no significant changes in these proportions could be observed in all but one site. In this particular site a steady decrease of coccoid cells and a simultaneous increase of rods was observed after 21 days. Actinomyces odontolyticus was first detected at Day 21 and Fusobacterium spp. were first detected at Day 42; at Day 120 small spirochetes were found for the first time, pus formation was noted clinically and a pocket probing depth of 6 mm was recorded. None of the other sites showed probing depths of over 3 mm or pus formation. In these clinically successful sites spirochetes were never seen. Fusobacteria could only be detected in 13 of 104 samples. Black‐pigmenting Bacteroides were found infrequently and no trend of increase was apparent in any site over the 180 days of monitoring.
Proteolytic profile of Treponema vincentii ATCC 35580 with special reference to collagenolytic and arginine aminopeptidase activity
Authors: Mäkinen Kauko K. , Syed Salam A. , Loesche Walter J. , Mäkinen Pirkko‐Liisa
Published: December 2007

The proteolytic profile of Treponema vincentii ATCC 35580 was studied using PZ‐PLGPA (phenylazobenzyloxycarbonyl‐L‐prolyl‐L‐leucylglycyl‐L‐prolyl‐D‐argi‐nine; a substrate of bacterial collagenases) and amino acid 2‐naphthylamides (2NA) as substrates. The cell extracts showed high activity toward PZ‐PLGPA, Na‐L‐arginyl‐2NA and Nγ‐L‐glutamyl‐2NA. Gel permeation chromatography revealed 2 major endopeptidases (I and II) hydrolyzing PZ‐PLGPA, the molecular weights of which were 75,000 and 23,000, respectively. Enzyme I was stable enough for subsequent fast protein liquid chromatography on an anion exchange column. The enzyme had a broad pH optimum of 6.5 to 7.5 with PZ‐PLGPA as substrate, hydrolyzed gelatin and was moderately inhibited by metal chelators, but was very sensitive to p‐chloromercuribenzoic acid (PCMB). Enzyme II with a pH optimum of 7 to 8 was more labile, quite sensitive to PCMB and moderately inhibited by chelators. A high‐molecular weight arginine aminopeptidase (mol. wt. > 200,000) was sensitive to PCMB and showed a value of 0.55 mM for Km in the hydrolysis of Na‐L‐arginyl‐2NA. The hydrolysis of PZ‐PLGPA and gelatin suggests that this organism may contain collagenolytic proteinases. Because the insoluble proteinase substrate Azocoll was not hydrolyzed, these enzymes may be active on soluble collagenous substances only. T. vincentii ATCC 35580 typifies an organism rich in PZ‐PLGPA‐endopeptidase, arginine aminopeptidase and γ‐glutamylpeptidase activity.
Gamma interferon modulation of prostaglandin E2 release from monocytes stimulated with lipopolysaccharides from Bacteroides intermedius, Bacteroides gingivalis, and Salmonella typhimurium
Authors: Garrison Scott W. , Nichols Frank C.
Published: December 2007

Lipopolysaccharides (LPS) from Bacteroides species are less potent than enterobacterial LPS preparations when compared by pyrogenicity and bone resorption assays and by the localized Schwartzman reaction. In this investigation, LPS preparations from Bacteroides intermedius and Bacteroides gingivalis were examined for their capacity to stimulate PGE2 release from human monocytes relative to identical doses of Salmonella typhimurium LPS. In addition, the capacity of recombinant gamma interferon (IFN‐γ) to potentiate PGE2 release was examined with each LPS preparation. Monocytes, separated by counter flow centrifugation, were exposed to LPS (1 ng/ml, 100 ng/ml and 10 ng/ml) alone or in combination with IFN‐γ (10 Units/ml). PGE2 levels (measured by RIA) were determined in monocyte culture supernatants exposed during the following incubation periods: 0‐8, 8‐24, 24‐48, and 48‐72 h. Monocytes treated with Salmonella LPS released 2 to 3‐fold greater amounts of PGE2 than cells treated with Bacteroides species LPS preparations. Although IFN‐y alone did not stimulate PGE2 release, Bacteroides‐elicited PGE2 release was siginificantly increased when monocytes were cultured concomitantly with IFN‐γ. PGE2 release elicited by Salmonella LPS was not significantly affected by interferon. These findings indicate that IFN‐γ can markedly potentiate the release of PGE2 from monocytes stimulated with Bacteroides LPS. Furthermore, the observed weakness of these LPS preparations relative to Salmonella LPS can be largely overcome by co‐treating monocytes with IFN‐γ.
Phospholipase A2: a possible virulence factor of Capnocytophaga ochracea
Authors: Sandholm Leena , Mahlberg Kaj , Jousimies‐Somer Hannele
Published: December 2007

The phospholipase A2 (PLA2) activity of 14 Capnocytophaga ochracea and 5 Bacteroides intermedius strains were measured with a radio assay. C. ochracea strains showed PLA2 activity with a mean of 21.4 ± 2.2 μg liberated fatty acid. B. intermedius, a known PLA2 producer, reached in our assay a mean of 26.8 ± 6.4. All the strains studied released free fatty acids slowly from the substrate: 4–6‐day incubation was needed to reach the maximum activity. Capnocytophaga isolated from the diseased and healthy gingival pockets of patients with localized juvenile periodontitis (LJP) showed a tendency of producing more PLA2 during the 2 first days of incubation than isolates from healthy controls or the B. intermedius strains. This tendency disappeared after day 3, and B. intermedius strains were more potent than C. ochracea on days 4–6. The activity was independent of the two bacterial culture media used in this investigation. We report PLA2 activity as a new possible virulence factor for C. ochracea.
Fatty acids and sugars in lipopolysaccharides from Bacteroides intermedius, Bacteroides gingivalis and Bacteroides loescheii
Authors: Johne Berit , Olson Ingar , Bryn Klaus
Published: December 2007

Lipopolysaccharide (LPS, endotoxin) was isolated from Bacteroides intermedius, Bacteroides gingivalis and Bacteroides loescheii by phenol extraction, purified by ultracentrifugation and investigated chemically by gas chromatography and mass spectrometry. Twenty different fatty acids were found. The fatty acid composition differed between the bacterial species, and intraspecies variation was also recorded. All endotoxins contained 3‐hydroxy‐15‐methylhexadecanoic acid and 3‐hydroxy‐hexadecanoic acid as major hydroxy fatty acids. Additional fatty acids were straight chain or iso‐ or anteiso‐branched fatty acids, and straight chain or iso‐branced hydroxylated fatty acids. The sugar composition showed great variability between different strains of the same species. Heptose and 2‐keto‐3‐deoxyoctonate (KDO) were detected in LPS from strains of B. gingivalis and B. intermedius. A tentatively identified glucosamine disaccharide was detected in all three Bacteroides species. This is indicative of lack of phosphorylation in the lipid A backbone, which is in concordance with the low general toxicity of Bacteroides LPS.
Enumeration of cultivable black‐pigmented Bacteroides species in human subgingival dental plaque and fecal samples
Authors: Okuda Katsuji , Fukumoto Yutaka , Takazoe Ichiro
Published: December 2007

The distribution of black‐pigmented Bacteroides species among 468 isolates from human subgingival dental plaque and feces from 20 adults selected from periodontally healthy, gingivitis and periodontitis groups is reported. Bacteroides intermedius was detected in all dental plaque samples. Bacteroides gingivalis, Bacteroides melaninogenicus and Bacteroides loescheii were isolated from 8, 3 and 2 dental plaques, respectively. Bacteroides denticola and Bacteroides levii were each detected in one dental plaque. Only 3 fecal samples contained black‐pigmented Bacteroides, identified as Bacteroides carporis, with a frequency ranging from 0.001 to 0.06% of total colonies on non‐selective blood agar plates.
A common antigen of Treponema denticola and other Treponema species detected by monoclonal antibody
Authors: Fukumoto Y. , Kato T. , Ishihara K. , Seida K. , Takazoe I. , Okuda K.
Published: December 2007

Murine monoclonal antibodies against Treponema denticola were produced. One monoclonal antibody (MSA257) reacted with 34,000 dalton antigens of all T. denticola strains, including ATCC strains and our isolates. This monoclonal antibody also reacted with antigens of other treponema strains tested.
Activity of amine‐stannous fluoride combination and chlorhexidine against some aerobic and anaerobic oral bacteria
Authors: Meurman Jukka H , Jousimies‐Somer Hannele , Suomala Päivi , Alaluusua Satu , Torkko Heini , Asikainen Sirkka
Published: December 2007

The in vitro susceptibility of 128 bacterial strains was tested to amine fluoride‐stannous fluoride (AmF + SnF) and chlorhexidine (CHX) solutions. Actinobacillus actinomycetemcomitans, Streptococcus mutans, and Bacteroides intermedius were among the species investigated. The 50% and 90% minimal inhibitory concentrations (MICs) were assessed by an agar dilution method. The MIC ranges for A. actinomycetemcomitans were 2–32 μ/ml for CHX and 0.25–64 μ/ml for AmF + SnF. The respective values for S. mutans were 0.5–8 μ/ml (CHX) and 2–8 μg/ml (AmF + SnF); and 4–8 μg/ml (CHX) and 2–4 μg/ml (AmF + SnF) for B. intermedius. Streptococcus faecallis and Staphylococcus aureus were most resistant of the control strains (MIC 64 μg/ml to CHX and 32 μg/ml to AmF + SnF, respectively). Thus, both solutions tested exerted a definite inhibitory action on the dental plaque pathogens studied.
Glucosyltransferases of Streptococcus sobrinus C211 are both stimulated and inhibited by hydrogen peroxide
Authors: McAlister D. , Nambiar S. , Taylor K. G. , Doyle R. J.
Published: December 2007

There are 2 glucosyltransferases (GTF) produced by Streptococcus sobrinus C211. One enzyme, GTF‐S, produces a water‐soluble glucan that is a‐1,6‐linked, with short a‐1,3 branches, and the other enzyme, GTF‐I, produces a water‐insoluble glucan that is a‐1,3‐linked with a‐1,6 branches. Hydrogen peroxide was found not only to be a potent inhibitor of GTF activity, but also a stimulator of GTF activity when employed at relatively low concentrations. At 0.88 M, H2O2 completely inhibited insoluble glucan synthesis, whereas at a 0.29 M concentration, H2O2 enhanced synthesis of the same glucan. Soluble glucan synthesis was also inhibited by H2O2 at 1.47 M. Low concentrations of hydrogen peroxide with GTF‐S, however, caused the enzyme to convert from soluble glucan production to insoluble glucan production. 13‐Nuclear magnetic resonance spectra of glucans produced by peroxide‐treated GTF confirmed that the production of a‐1,3 linked glucans was increased with H2O2‐treated GTF‐S.
Streptococcus mutans, not detected?
Authors: Alaluusua S. , Grönroos L. , Kleemola‐Kujala E.
Published: December 2007

The growth of Streptococcus mutans was followed for three years in 24 healthy 12‐17 year‐old children, who were selected for the study on the basis of undetectable levels of salivary S. mutans. The saliva samples were cultured by a dip‐slide method based on mitis‐salivarius agar supplemented with sucrose and bacitracin. At the final occasion, additional examination of plaque and saliva of 10 children using TSY20B agar was performed. During the 3‐year study period, S. mutans was found in saliva samples from 15 children on one or more of the 4 test occasions, suggesting that most ‘S. mutans negative individuals’ were those in whom S. mutans could not be temporarily detected. The additional examination of plaque did not increase the number of ‘S. mutans‐positive individuals’.
The predominant cultivable microbiota of crevicular epithelial cells
Authors: Dzink J. L. , Gibbons R. J. , Childs W. C. , Socransky S. S.
Published: December 2007

The purpose of the present investigation was to compare the composition of the predominant cultivable microbiota associated with gingival crevicular epithelial cells with that of the unattached microbiota recovered from the same site. Samples were taken from 2 diseased sites from 8 periodontal patients, by scraping the epithelial lining of the pocket with a curette. The epithelial cells were separated from the unattached subgingival bacteria by centrifugation in a reduced 50% Percoll density gradient. Epithelial cells formed a band at the top of the gradient and were removed separately from the unattached bacteria located at the base. Each layer was dispersed, diluted and plated on Trypticase soy agar with 5% sheep blood and 50 isolates were characterized from each sample. The microorganisms associated with the epithelial layer harbored 5‐ to 20‐fold higher mean percentages of Bacteroides gingivalis, Bacteroides intermedius and Peptostreptococcus micros. The layer of unattached organisms exhibited 4‐ to 10‐fold higher mean percentages of Streptococcus uberis, Capnocytophaga ochracea, Eikenella corrodens and Veillonella parvula.
Intra‐oral colonization of macaque monkeys by Actinobacillus actinomycetemcomitans
Authors: Beighton David , Taichman Norton S. , Simpson David L. , Dirienzo Joseph M. , Johnson Newell W.
Published: December 2007

Actinobacillus actinomycetemcomitans was acquired by captive Macaca fascicularis 3 to 6 months after birth, and all monkeys aged over 6 months harbored detectable levels. This microorganism was most frequently isolated from the gingival plaque of the incisor (and other) teeth compared with other oral sites. Strains were leukotoxic by bioassay and Western blot analysis. Antibodies in macaque serum contained neutralized the leukotoxin of a human A. actinomycetemcomitans strain. High titres of maternal neutralizing anti‐leukotoxin antibodies were detected in neonates; the titre then fell rapidly so that by 6 months the antibody liter was zero. Antileukotoxin antibody production was detected after 6 months of age, rapidly reaching a high level within 2 years after birth. The presence of leukotoxic strains of A. actinomycetemcomitans in the gingival region did not appear to be correlated with an increase in susceptibility to periodontal disease.
Non‐isotopic DNA probes for the identification of subgingival microorganisms
Authors: Smith G. L. F. , Socransky S. S. , Smith C. M.
Published: December 2007

The purpose of the present investigation was to examine the potential of non‐isotopic DNA probes to identify pure cultures in predominant cultivable micro‐biota studies. Non‐isotopic DNA probes to 7 subgingival species were prepared by 2 methods. In the first, biotin‐labelled probes were prepared by nick translation. In the second, single‐stranded DNA was covalently linked to horseradish peroxidase via polyethyleneimine. The relative sensitivities and specificities of these probes were tested against pure cultures of a range of subgingival species. Aliquots of broth cultures were standardized by optical densities, placed on nitrocellulose or Whatman 541 filters and then treated to lyse the cells, denature and fix DNA to the filter. Using a streptavidin‐alkaline phosphatase detection system, 104–105 cells were detected by homologous biotin‐labelled probes. Horseradish peroxidase‐labelled probes were approximately one order of magnitude less sensitive. Non‐specific reactions with unrelated species, displayed by both biotin‐ and horseradish peroxidase‐labelled probes, were eliminated by treatment of filters with proteinase K and organic solvents. Cross‐reactions between closely related species could be discriminated by comparing reaction intensities of the test strains with probes to the each of the cross‐reacting species involved. Thus, nonisotopic DNA probes could be used for the rapid identification of subgingival isolates. The technique could also be used for the recognition and grouping of strains of unknown species. A probe made to the strain of an unknown species may be used to rapidly screen hundreds of unknown isolates for related strains.
SDS‐PAGE analysis of protein and lipopolysaccharide of extracellular vesicules and Sarkosyl‐insoluble membranes from Bacteroides gingivalis
Authors: Deslauriers Manon , Eidhin Déirdre ní , Lamonde Louise , Mouton Christian
Published: December 2007

We have compared outer membranes (OM) of Bacteroides gingivalis ATCC 33277 isolated by the following 3 techniques: 1) high speed centrifugation after mechanical cell shearing; 2) sonication of the bacteria, followed by solubilization of the cytoplasmic membrane with N‐Laurylsarconsinate (Sarkosyl), after which the Sarkosyl‐insoluble membranes were recovered by centrifugation; 3) ammonium sulfate precipitation of extracellular vesicules from culture supernatant, followed by centrifugation and dialysis. Electron microscopy showed that the 3 preparations consisted of closed vesicules. Analysis by SDS‐PAGE revealed that all 3 contained up to 28 polypeptides, most of which were common to each extract. The extracellular vesicules and Sarkosyl‐insoluble preparation yielded similar protein patterns, although quantitative differences were observed. The sheared‐cell preparation contained 8 additional proteins. The level of contamination of OM material by peptidoglycan and cytosol components was 1.8% in the sheared‐cell preparation, and was null or lower than 0.8% in the other preparations. All 3 preparations showed the presence of LPS with a multiple banding pattern typical of smooth LPS. The sheared‐cell preparation had a slightly lower LPS content than the other 2 preparations. Since extracellular vesicules are naturally released during bacterial growth, and are relatively simple to obtain, such native entities seem an appropriate source of OM components for use in studying the immunobiology of B. gingivalis surface antigens.
Maternal caries incidence and salivary close‐contacts with children affect antibody levels to Streptococcus mutans in children
Authors: Aaltonen Antti S. , Tenovuo Jorma , Lehtonen Olli‐Pekka , Saksala Ritva
Published: December 2007

Serum and salivary immunoglobulins and antibodies reactive with Streptococcus mutans were determined in 67 5–8‐year‐old children. The children of mothers whose caries incidence rates exceeded the median value had significantly more serum IgG antibodies to S. mutans than those with a lower maternal caries activity (p < 0.05). The children (n = 14) who had been exposed to frequent maternal salivary close‐contacts in their first year had significantly higher (p < 0.05) serum total specific IgG antibodies but significantly lower (p < 0.01) high‐avidity IgG antibodies to S. mutans than the other children (n = 53) with less frequent close‐contacts. The maternal caries incidence rates were significantly positively associated with children's dfs/DFS‐indices (r = 0.41; p < 0.001). However, the high maternal caries incidence did not increase the risk of caries in those children whose mothers’ saliva contained high amounts of lactobacilli during the first nursing year, when compared with matched children with a low maternal level of lactobacilli. This was possibly due to the fact that the former children had significantly (p < 0.05) more anti‐S. mutans IgG antibodies in their sera than the latter.
Primary reservoirs of Streptococcus mutans and their relationship to caries experience in adults with good oral hygiene
Authors: Keene Harris J. , Folsom Karen S. , Basel Denise A. , Puente Edward S.
Published: December 2007

Primary reservoirs of Streptococcus mutans were identified in a group of 21 adults with intact dentitions and good oral hygiene by obtaining multiple plaque samples from all available tooth surfaces. Routine cultural methods and a rapid plate scoring method employing a 7‐point ordinal scale were used to assess S. mutans levels. Oral hygiene status (DI‐S) and caries experience (DMFT and DMFS) were determined clinically. Primary S. mutans reservoirs (high scores) were restricted essentially to the posterior interproximal areas and occasionally in the occlusal pits and fissures of partially erupted mandibular third molars. An anterior to posterior gradient of increasing S. mutans scores was observed for interproximal sites. Oral hygiene scores correlated poorly with DMFT, DMFS and the S. mutans scores obtained for different anatomic locations.
An in vitro method to study the adherence of bacteria to saliva‐treated tooth enamel sections
Authors: Sweet Simon P. , MacFarlane T. Wallace , Samaranayake Lakshman P.
Published: December 2007

An in vitro bacterial adherence assay which employed human tooth enamel sections precoated with saliva and an epifluorescent staining technique with acridine orange was developed. The assay was used to study the adherence properties of fresh and type strains of the following oral bacterial species: Bacteroides gingivalis, Bacteroides intermedius, Capnocytophaga species, Haemophilus aphrophilus, Actinobacillus actinomycetemcomitans, Peptostreptococcus species, Veillonella species, Actinomyces israelii, Streptococcus salivarius and Streptococcus sanguis. Approximately half of the bacteria tested adhered well to enamel, including the fresh isolates of B. gingivalis, B. intermedius, Veillonella species and S. sanguis. Adherence did not correlate in all cases with the known distribution of these species in vivo. Three‐quarters of the fresh strains adhered better than the type strains of the same species. The assay method is an alternative to the widely used hydroxyapatite bead assay.
The incidence of periodontopathic microorganisms in young children
Authors: Frisken K. W. , Higgins T. , Palmer J. M.
Published: December 2007

Thirty‐six children in 4 cohorts of 0–1 week, 1–6 months, 1–2 years and 2–21/2 years of age were examined for the presence of black‐pigmented Bacteroides species and some other bacteria suspected of being involved in the subsequent development of periodontal destruction. None of the sought‐after bacteria were detected in the first week of life. Bacteroides intermedius and Bacteroides melaninogenicus were detected as early as 1 month after birth. Both of these bacteria were detected in 16–37% of children in the different cohorts. Bacteroides denticola was detected in one child. Other black‐pigmented species including Bacteroides gingivalis and Bacteroides loescheii were not detected. Eikenella corrodens was detected in 62% of children under 6 months. Capnocytophaga spp. were detected in 12% and Fusobacterium nucleatum in 25% of children in this age group. With increasing age there was a trend towards an increase in the number of children with F. nucleatum but other bacteria were detected in similar numbers of children throughout the 3 older cohorts. Actinobacillus actinomycetemcomitans was not detected at any age.
Glucosyltransferase production by Streptococcus sanguis Challis and comparison with other oral streptococci
Authors: Buchan Robyn A. , Jenkinson Howard F.
Published: December 2007

Glucosyltransferase (GTF) activity in batch cultures of Streptococcus sanguis strain Challis in defined medium was maximum at peak growth and declined rapidly on further incubation into stationary phase. Activity was present in spent culture medium and was associated with 2 polypeptides of approximate Mrs 170 kDa (90% of activity) and 155 kDa (about 10% of activity). Other S. sanguis strains produced similar antigenically‐related polypeptides but with varying activities, and antibodies to the S. sanguis enzyme did not react with enzymes produced by other species of oral streptococci. Increasing the [Na+] reduced GTF production by S. sanguis strains Challis and NCTC 7865, and by Streptococcus sobrinus, but not by Streptococcus salivarius. Addition of Tween 80 to cultures caused a rapid inhibition of GTF synthesis by strain Challis, but not by strain NCTC 7865. Benzyl alcohol had a slower and less inhibitory effect on GTF production by strain Challis. Tween 80 generally inhibited to varying degrees GTF production by other oral streptococci though in S. sobrinus it was stimulated. The results suggest controls operating on GTF synthesis and secretion by different strains of oral streptococci appear to be diverse.
Denture stomatitis in the elderly
Authors: Cumming C. G. , Wight C. , Blackwell C. L. , Wray D.
Published: December 2007

A study was carried out of 121 elderly edentulous individuals living in institutionalised homes in the Lothian Region, Scotland to determine the prevalence of yeasts and associated oral disease. Clinical examinations found that 65(54%) of the individuals suffered from denture stomatitis, and yeasts were recovered from 51(78%) of these individuals. The main yeasts isolated were Torulopsis glabrata and Candida albicans. Culture of saliva samples produced a slightly higher recovery rate of yeasts compared with swabbing of the floor of mouth and palate. The number of cigarettes smoked per day had a significant positive effect on the presence of denture stomatitis. No difference in disease state was shown between secretors and non‐secretors of blood group antigens in saliva. This study demonstrates a significant level of oral mucosal infection in an institutionalised elderly population.
Outer membrane proteins of Actinobacillus actinomycetemcomitans and Haemophilus aphrophilus studied by SDS‐PAGE and immunoblotting
Authors: Bolstad Anne Isine , Kristoffersen Tore , Olsen Ingar , Preus Hans R. , Jensen Harald B. , Vasstrand Endre N. , Bakken Vidar
Published: December 2007

This investigation characterized and compared outer membrane proteins (OMP) of the closely related Actinobacillus actinomycetemcomitans and Haemophilus aphrophilus by means of SDS‐PAGE patterns and reactions on immunoblots with rabbit antiserum against A. actinomycetemcomitans FDC Y4. Reactions with serum from a patient with Papillon Lefévre syndrome (PLS), from whom periodontal wild strains of A. actinomycetemcomitans had been isolated, were also studied. OMP were purified with selective solubilizalion from lyophilized cells of 10 wild and 4 reference strains of A. actinomycetemcomitans and 4 reference strains of H. aphrophilus. OMP profiles from wild and reference strains of A. actinomycetemcomitans were similar while those from A. actinomycetemcomitans and H. aphrophilus differed. The most prominent difference was absence of a heat modifiable protein in H. aphrophilus strains. Immunoblotting revealed strong common antigens in most strains, including a heat modifiable protein with mol wt 34 kDa, as well as a 29 kDa and a 16.5 kDa protein. Treatment with pronase and sodium periodate confirmed the protein nature of the major OMP antigens.
Age and sex relationships of superinfecting microorganisms in periodontitis patients
Authors: Slots Jørgen , Feik Diane , Rams Thomas E.
Published: December 2007

The occurrence by age and sex of subgingival enteric rods and pseudomonads, yeasts, and staphylococci was studied in 3075 “refractory” periodontitis patients referred for microbiological analysis. Each subject contributed a pooled subgingival sample obtained from 3 deep periodontal pockets with paper points. Selective and nonselective media and commercial identification kit systems were used for microbial isolation and speciation. Females constituted about 60% of the study subjects, and almost one‐third of all patients were in their forties. Females (47.3%) showed a higher prevalence of the study organisms than males (43.9%). Older females (15.9%) and males (15.3%) revealed significantly higher prevalences of enteric rods and pseudomonads than younger individuals (10.9%), and older infected females yielded significantly higher viable counts than younger infected females. The sexes demonstrated a similar prevalence of staphylococci (about 28%), but younger infected females and males showed significantly higher viable counts than older infected individuals. No sex or age relationships were found for yeasts (about 14% of individuals infected). The high level of subgingival enteric rods and pseudomonads in some individuals may be important in the pathogenesis of geriatric and other forms of periodontitis and may have therapeutic implications.
Dental caries in congenitally athymic rats
Authors: Stack Wendy E. , Taubman Martin A. , Tsukuda Tomio , Smith Daniel J. , Ebersole Jeffrey L. , Kent Ralph
Published: December 2007

The importance of the immune response in dental infection was evaluated in heterozygous (rnu/+) normal and homozygous (rnu/rnu) congenitally athymic “nude” Rowett rats. Animals of both types were infected, or immunized and infected, with mutans streptococci (Streptococcus sobrinus strain 6715). The mean numbers of S. sobrinus cells recovered from the nude rats were higher than those from comparable (immune/nonimmune) normal rats in 10 of 12 possible comparisons. Also, S. sobrinus constituted a greater percentage of the total streptococci in the nude rats compared with normal animals (6 of 6 possible comparisons). Antibody to S. sobrinus whole cells or to S. sobrinus glucosyltransferase from nude rats in serum or in saliva was significantly lower (or absent) than that of comparable normal rats. This was seen after infection, but was most pronounced after immunization (and infection). Dental caries was also significantly elevated in the congenitally athymic animals. Immunologic deficiency of congenitally athymic rats can lead to a greater infection level with mutans streptococci and increased dental caries.
The distribution and frequency of Fusobacterium nucleatum subspecies in the human oral cavity
Authors: Gharbia S. E. , Shah H. N. , Lawson P. A. , Haapasalo M.
Published: December 2007

Three reference strains of Fusobacterium nucleatum and 32 human oral isolates were compared by a variety of physiological tests, enzyme electrophoretic profiles, SDS‐PAGE patterns, DNA base composition and hybridization to test their possible site specificity and frequency of the recently described subspecies of F. nucleatum. Nine of the 11 isolates assigned to F. nucleatum subspecies nucleatum were from diseased sites, whereas isolates from healthy sites were all identified as F. nucleatum subspecies polymorphum or F. nucleatum subspecies fusiforme. Strains of the latter subspecies were the least frequently isolated (2 of 32). These results, although still inconclusive because of the relatively small sample size, nevertheless confirmed the heterogeneity of F. nucleatum and indicate that most human oral isolates from subgingival sites probably belong to F. nucleatum subspecies nucleatum.
Analysis of in vitro lymphoproliferative responses and antibody formation following subcutaneous injection of Actinobacillus actinomycetemcomitans and Wolinella recta in a murine model
Authors: Chen Priscilla B. , Davern Lynda Beth , Neiders Mirdza E. , Reynolds Homer S. , Zambon Joseph J.
Published: December 2007

The potential of Wolinella recta and Actinobacillus actinomycetemcomitans to cause abscesses and induce an immune response was tested in BALB/c mice. Mice were injected subcutaneously with W. recta, A. actinomycetemcomitans or a mixture of these 2 microorganisms. Mice injected with A. actinomycetemcomitans alone, or with both organisms, demonstrated abscesses at the injection site 2 days later, from which pure cultures of A. actinomycetemcomitans were isolated. Mice injected with W. recta had small, flat abscesses at the injection site from which no bacteria could be cultured. W. recta was cultured from injection sites only when associated with A. actinomycetemcomitans. Mice developed positive serum IgG antibody responses to W. recta by 20 days post‐injection but not to A. actinomycetemcomitans whether injected in pure culture or mixed infection. In vitro lymphoproliferative responses following injection of W. recta and/or A. actinomycetemcomitans resulted in increased lymphocyte reactivity in unstimulated cultures and decreased in vitro responses to phytohemagglutinin. In vitro lymphoproliferative responses to Escherichia coil LPS or Salmonella typhimurium LPS were depressed in mice injected with A. actinomycetemcomitans, but not in mice injected with W. recta.
Divergent effect of the anaerobic bacteria by‐product butyric acid on the immune response: suppression of T‐lymphocyte proliferation and stimulation of interleukin‐1 beta production
Authors: Eftimiadi C. , Stashenko P. , Tonetti M. , Mangiante P. E. , Massara R. , Zupo S. , Ferrarini M.
Published: December 2007

The effects of short‐chain fatty acids (SCFA) produced by anaerobic bacteria, namely propionic, butyric and iso‐butyric on T‐cell proliferation was investigated. A dose‐dependent inhibition of both phytohemagglutinin‐induced blastogenesis and mixed lymphocyte culture was observed in the millimolar range of SCFA concentrations. The tested SCFA displayed different levels of suppression. The degree of activity was in the following order: butyrate > propionate > iso‐butyrate. T‐cell inhibition was partially reversed, at least for propionic and iso‐butyric acids, by increasing the concentration of macrophages in the assay system. Furthermore, butyric acid displayed an interesting biphasic stimulation of monocyte interleukin‐1 beta production, a cytokine with a powerful bone‐resorbing activity. Since millimolar concentrations of SCFA are present in gingival fluid from periodontal pockets, the observed results support the role of these byproducts of anaerobic metabolism in the pathogenesis of periodontal diseases.
Intracellular xylitol‐phosphate hydrolysis and efflux of xylitol in Streptococcus sobrinus
Authors: Trahan Luc , Néron Sonia , Bareil Monique
Published: December 2007

The parental strain Streptococcus sobrinus (Streptococcus mutans ATCC 27352), which is known to transport, phosphorylate and accumulate xylitol intracellularly as nonmetabolizable xylitol‐phosphate (xylitol‐sensitive (Xs) strain) and its xylitol‐resistant (XR) spontaneous mutant were used to further investigate the inhibitory action of xylitol on oral streptococci. Fructose‐grown XR cells did not accumulate xylitol‐phosphate, indicating that the inducible fructose PTS is incapable of transporting the pentitol. The intracellularly accumulated pentitol‐phosphate by the Xs cells did not prevent the subsequent uptake and degradation of glucose or fructose, despite a drop in the PEP pool and a 50% inhibition of the glucose but not the fructose catabolism. Intracellular dephosphorylation of the pentitol‐Phosphate and release of xylitol in the extracellular medium resulted in a rapid decrease of the intracellular level of this nonmetabolizable product. A Mg++‐ or Mn++‐independent sugar‐phosphate hydrolysing activity capable of splitting xylitol‐phosphate was demonstrated in both Xs and XR strains. Preincubation in the presence of N1‐ethylmaleimide (NEM) and xylitol or NEM and fructose resulted m the subsequent inhibition of both xylitol uptake and efflux. The efflux kinetic at various temperatures is compatible with a facilitated diffusion by the phosphotransferase system EIIfru without, however, excluding the existence of an additional exit route, but it excludes a simple diffusion exit process. The results are consistent with the existence of a xylitol futile cycle contributing to the growth‘inhibition of S. sobrinus by the pentitol without excluding a toxic effect of xylitol‐phosphate. Discrepancies in the literature on the action of xylitol on S. mutans could be explained in the light of the evidence presented.
In vitro activity of chlorhexidine against enteric rods, pseudomonads and acinetobacter from human periodontitis
Authors: Slots Jørgen , Rams Thomas E. , Schonfeld Steven E.
Published: December 2007

Fifty‐eight periodontal isolates of the families Enterobacteriaceae and Pseudomonadaceae, and the genera Acinetobacter and Achromobacter were studied to determine their susceptibility to Peridex® (0.12% chlorhexidine digluconate solution; Procter & Gamble). In an agar dilution assay, about 50% of the study strains grew in the Presence of 70 μ/ml of Chlorhexidine. Enterobacter cloacae, Klebsiella neumoniae, Pseudomonas aeruginosa, Pseudomonas cepacia, and Serratia marcescens comprised the most resistant species. Studies are needed to determine the microbiological and clinical effects of chlorhexidine usage in patients infected with enteric rods and pseudomonads.
Adaptation by Streptococcus mutans to acid tolerance
Authors: Hamilton I. R. , Buckley N. D.
Published: December 2007

Our previous continuous culture studies with strains of Streptococcus mutans have indicated that the organism has the capacity of adapt to growth in acidic environments. This study was undertaken to examine this question in more detail. S. mutans Ingbritt and the phosphotransferase system (PTS)‐defective mutant, S. mutans DR0001/6, were grown in continuous culture at pH 7.5 and 5.5 or 5.1, and the pH optimum for glucose uptake and glycolysis and the capacity of the cells to generate pH gradients were determined over the pH range 4.5 to 8.0 with steady state, washed cells. In addition, the proton permeability of the cells was measured over the pH range by an acid pulse technique. The results indicate that the pH optimum for glucose uptake by S. mutans Ingbritt grown at pH 7.5 was 7.5 and this optimum shifted to 7.0 and 6.0 for cells grown at pH 5.5 and 5.1, whereas with the S. mutans DR0001/6, the optimum shifted from 7.5 to 7.0 for the pH 5.5 cells. A similar shift in the pH optimum for glycolysis was observed for the 2 strains, and this was particularly pronounced for cells incubated with glucose in the presence of gramicidin to dissipate proton gradients. The capacity of the cells to generate pH gradients was related to their metabolic activity, and although larger gradients were not formed by the pH 5.5 cells, these cells were nevertheless capable of maintaining gradients at a lower pH; S. mutans DR0001/ 6 generated 2‐fold larger pH gradients at pH 5.5 than S. mutans Ingbritt. In addition, activity for the membrane‐associated proton‐extruding ATPase in S. mutans Ingbritt increased 4‐fold as the pH of growth was decreased from 8.0 to 5.0. The most striking difference between cells grown at pH 7.5 and 5.5 was observed in the proton permeability profiles for the 2 organisms. The pH for minimum proton permeability for the pH 7.5‐grown cells of S. mutans Ingbritt Was 6.4, whereas that for pH 5.5 cells was 5.0; the corresponding values for S. mutans DR0001/6 were pH 5.6 and 4.6 for the pH 7.5 and 5.5 cells, respectively. This indicates that the cells compensate for the lower external pH by decreasing the permeability of protons into the cell at the lower pH values. Collectively, these results indicate that prolonged growth of S. mutans in an acidic environment, such as might be found in fissures or carious lesions, results in significant changes in cell physiology that confer increased acidurance.
Variance in recovery of periodontitis‐associated bacteria caused by sampling technique and laboratory processing
Authors: Wikström M. , Renvert S. , Dahlén G. , Johnsson T.
Published: December 2007

The influence of sampling procedure and of laboratory processing on the recovery of Bacteroides gingivalis, Bacteroides intermedius, and Actinobacillus antinomycetemcomitans from periodontitis sites was evaluated. Thirty‐three adult subjects with severe periodontitis participated in the study. In all, 462 samples from 81 sites were examined. The samples were taken using the paper point technique. The cultivations were performed by use of enriched Brucella agar for determination of total colony‐forming units and Bacteroides species, and trypticase soy bean agar for determination of A. actinomycetemcomitans. The risk of getting a false negative result was 4% for B. gingivalis, 20% for B. intermedius, and 38% for A. actinomycetemcomitans. It was considerably reduced if duplicate samples were taken. The sampling procedure alone explained up to 98% of the false‐negative results.
Metabolism of 17B‐estradiol by oral Streptococcus mutans, Streptococcus sanguis, Bacillus cereus and Candida albicans
Authors: Ojanotko‐Harri Anita , Laine Merja , Tenovuo Jorma
Published: December 2007

The ability of oral isolates of Streptococcus mutans, Streptococcus sanguis, Bacillus cereus and Candida albicans to metabolize 17ß‐estradiol was analyzed by thin‐layer chromatography using 4–14C‐estradiol as the substrate. All test microorganisms metabolized 17ß‐estradiol. Estrone was the main metabolic product, except for B. cereus, which converted 17ß‐estradiol mainly to unidentified, more polar metabolites. S. sanguis and B.cereus had the most active metabolism but S. mutans and C. albicans were also active.
Ecology of viridans streptococci in the oral cavity and pharynx
Authors: Frandsen E. V. G. , Pedrazzoli V. , Kilian M.
Published: December 2007

Recently published taxonomic studies of viridans streptococci have resulted in several changes in the nomenclature and definition of oral streptococcal species. With this background, the ecology of streptococci in the oropharyngeal cavities was reinvestigated. The results based on the examination of 1426 streptococcal isolates confirmed and extended earlier findings. Apart from mature supragingival plaque, which contained a mixture of all orally encountered streptococci, each site showed a characteristic streptococcal flora. Initial dental plaque formation is primarily associated with Streptococcus sanguis, Streptococcus mitis biovar 1 and Streptococcus oralis (20). Our investigation showed that S. sanguis and S. mitis biovar 1 were the most prominent streptococci, also on buccal mucosa. In contrast, S. oralis was almost exclusively found in initial dental plaque. Streptococcus gordonii, formerly part of S. sanguis, was found in small numbers on the oropharyngeal mucosa and in mature supragingival plaque. The dorsum of the tongue was dominated by S. mitis biovar 2 and Streptococcus salivarius, the latter of which was predominant also on the pharyngeal mucosa. Streptococcus anginosus was by far the most predominant streptococcus in subgingival plaque. Immunoglobulin A1 (IgA1) protease‐producing streptococci were primarily isolated from initial dental plaque and from the buccal mucosa. This lends further support to the concept of IgA1 proteases being important for the ability of streptococci to evade the local immune defence during their initial colonization of certain oral surfaces.
Crevicular IgG antibodies and recovery of locally implanted Streptococcus mutansR in humans
Authors: Camling E. , Gahnberg L. , Krasse B.
Published: December 2007

This study was undertaken with the aim of examining the effect of highly different IgG antibody activities in gingival crevicular fluid (GCF) on the elimination of a streptomycin‐resistant strain of Streptococcus mutans (S. mutansR) topically implanted on the tooth. Two groups of people were selected for the study, one with high and one with low specific IgG antibody activity (IgG antibody activity against S. mutansR) in GCF. During an experimental period of 15 d the specific IgG antibody activity in GCF in the same individual stayed on a relatively constant level. Between individuals, however, the specific IgG antibody activity varied considerably. The number of indigenous mutans streptococci and the number of implanted bacteria on the same tooth surface were strongly correlated. The implanted S. mutansR strain was rapidly eliminated in all subjects. No difference in the elimination of the implanted strain of S. mutansR could be demonstrated between the groups of high and low specific IgG antibody activity.
Periodontal bone level and gingival proteinase activity in gnotobiotic rats immunized with Bacteroides gingivalis
Authors: Klausen Bjarne , Evans Richard T. , Ramamurthy Nangavaram S. , Golub Lorne M. , Sfintescu Cornelia , Lee Jin‐Yong , Bedi Gurrinder , Zambon Joseph J. , Genco Robert J.
Published: December 2007

Bacteroides gingivalis is associated with various forms of periodontal disease. To assess the role of the immune response in modulating B. gingivalis‐associated Periodontal disease, the effect of immunization of B. gingivalis‐induced periodontal bone loss was evaluated in gnotobiotic rats. Male Sprague‐Dawley rats immunized with various doses of whole cells or sham‐immunized with incomplete Freund's adjuvant were monoinfected with B. gingivalis in carboxymethylcelulose by gavage. Two additional groups served as either sham‐immunized or Untreated germ‐free controls. Forty‐two days after infection, all rats were killed, Periodontal bone level was assessed morphometrically and radiographically, and gingival proteinase (mammalian collagenase and acid cathepsin) activity was assessed biochemically. B. gingivalis was present in oral samples from all monoinfected rats, and no contaminating bacteria were detected in any oral or fecal sample. Animals immunized with B. gingivalis cells had elevated serum and saliva antibodies to whole cells and partially purified fimbriae from B. gingivalis. Infected sham‐immunized rats had significantly more periodontal bone loss than noninfected controls, whereas the periodontal bone level in infected rats immunized with 1010B. gingivalis cells was similar to that of the noninfected controls. The activities of gingival collagenase and cathepsin B and L were high in sham‐immunized infected rats and low in all other animal groups. In conclusion, it is possible to reduce B. gingivalis‐induced periodontal tissue loss in gnotobiotic rats by immunization.
A modified mitis salivarius medium for a caries diagnostic test
Authors: Kimmel Lida , Tinanoff Norman
Published: December 2007

A new medium, MSKB, composed of mitis salivarius agar base, sorbitol, kanamycin sulfate and bachracin, has been developed that is more selective for recovery of mutans streptococci (mutans) than the so called mitis salivarius bacitracin (MSB) medium. MSB and MSKB were compared for recovery and selectivity of mutans by plating saliva samples as well as pure cultures on both media. Sixty saliva samples were plated and counted for mutans and non‐mutans colonies. Thirty‐six samples had greater numbers of non‐mutans on MSB than on MSKB, and 14 of the 36 had non‐mutans colonies that could be visually confused with mutants. The recovery of mutans on MSKB was approximately 13% less than on MSB. The selectivity and recovery of MSB and MSKB were evaluated over 1–5 months of storage at 4°C. Streptococcus mutans anginosus grew on MSB after 1 month, but not on MSKB. Streptococcus mutans milleri type 2 grew on both media after 4 months.