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PubMed1982

Intestinal spirochaetosis: an electron microscopic study of an unusual case.

An unusual case of intestinal spirochaetosis is described. The rectum of a 34-year-old male, suffering from Crohn's disease and ankylosing spondylitis, was heavily infested by spirochaetes. Both absorptive and goblet cells were colonized. Spirochaetes were found not only on the luminal surface of these cells, but also within the cytoplasm, in occasional macrophages within the lamina propria and, even more surprisingly, within the occasional Schwann cell. The significance of these findings is discussed.

Adult↗
PubMed1995

Colonic tubular adenomas and intestinal spirochaetosis: an incompatible association.

Two cases of tubulovillous adenoma and adjacent colonic mucosa were studied in which intestinal spirochaetosis had heavily colonized the non-neoplastic but not the neoplastic epithelium. Ultrastructural and histochemical studies were performed and we postulate that the reason for this disparity is the normal microvillous pattern of the non-neoplastic epithelium which facilitates colonization by the spirochaetes.

Adenoma↗
PubMed1994

Localized prepubertal periodontitis in a 5-year-old child: investigations and clinical observations over a 3-year period.

A 5-year-old boy presented with persistent generalized gingival inflammation. Clinical and radiographic examination supplemented by immunological and microbiological investigation led to a diagnosis of localized prepubertal periodontitis. The child was subsequently monitored for 3 years and despite treatment there was continued bone loss related to his primary teeth. This case highlights the need for liaison between specialists in paediatric dentistry, periodontology, immunology and microbiology in order to diagnose prepubertal periodontitis and to establish a rational basis for treatment to prevent progression to juvenile periodontitis.

Aggressive Periodontitis↗
PubMed1979

Qualitative changes in dental plaque formation related to removable partial dentures.

A study was performed on the microbial composition of dental plaque developing on fifteen abutment teeth in nine partially edentulous subjects. Bacteria were counted in samples of plaque which had formed on vestibular surfaces, and on proximal surfaces facing edentulous spaces, during a period when dentures were not worn, and then for a period when dentures were being worn. It was found that the presence of removable partial dentures favoured a proliferation of spiral organisms.

Adult↗
PubMed2004

Mutations in ribosomal protein L3 and 23S ribosomal RNA at the peptidyl transferase centre are associated with reduced susceptibility to tiamulin in Brachyspira spp. isolates.

The pleuromutilin antibiotic tiamulin binds to the ribosomal peptidyl transferase centre. Three groups of Brachyspira spp. isolates with reduced tiamulin susceptibility were analysed to define resistance mechanisms to the drug. Mutations were identified in genes encoding ribosomal protein L3 and 23S rRNA at positions proximal to the peptidyl transferase centre. In two groups of laboratory-selected mutants, mutations were found at nucleotide positions 2032, 2055, 2447, 2499, 2504 and 2572 of 23S rRNA (Escherichia coli numbering) and at amino acid positions 148 and 149 of ribosomal protein L3 (Brachyspira pilosicoli numbering). In a third group of clinical B. hyodysenteriae isolates, only a single mutation at amino acid 148 of ribosomal protein L3 was detected. Chemical footprinting experiments show a reduced binding of tiamulin to ribosomal subunits from mutants with decreased susceptibility to the drug. This reduction in drug binding is likely the resistance mechanism for these strains. Hence, the identified mutations located near the tiamulin binding site are predicted to be responsible for the resistance phenotype. The positions of the mutated residues relative to the bound drug advocate a model where the mutations affect tiamulin binding indirectly through perturbation of nucleotide U2504.

Amino Acid Substitution↗
PubMed1979

Metronidazole in the treatment of tropical phagedenic ulcers.

In an uncontrolled preliminary trial, metronidazole administered orally to 30 patients was effective in resoving tropical phagedenic ulcers within a period of one to two weeks. The efficacy of this drug indicates the important role played by fusospirochetes in causing tropical ulcers.

Fusobacterium Infections↗
PubMed1987

Taxonomic study of spirochetes isolated from human periodontal lesions.

Nineteen strains of spirochetes obtained from subgingival plaque of 19 patients with advanced periodontitis were studied morphologically, biochemically, and genetically and compared with type strains of Treponema denticola and Treponema socranskii. The results showed that 16 strains which biochemically resembled T. denticola could be divided into two groups based on G + C content and DNA homology. Two isolates appeared to belong to the T. socranskii species. One intermediate size isolate did not fit any known Treponema species.

Adult↗
PubMed1990

Spirochetes in early lesions of necrotizing ulcerative gingivitis experimentally induced in beagles.

The presence of spirochetes and other bacteria during the induction of necrotizing ulcerative gingivitis (NUG) in beagle dogs was studied by transmission electron microscopy. NUG was induced by application of dental debris from diseased dogs to 4 beagles treated with corticosteroid. Biopsies of interdental papillae were collected during a period of 7 weeks. Spirochetes and other bacteria were observed in enlarged intercellular spaces between non-keratinized epithelial cells. Intracellular bacteria were found with and without surrounding vesicular spaces. The invasive spirochetes were mainly intermediately sized and of flagellar "4-8-4" configuration or higher. Bacterial invasion of the sulcular epithelium occurred before clinical evidence of NUG could be observed. It is concluded that invasion by intermediate spirochetes and other bacteria plays a role in initiating ulcerative gingivitis in beagles.

Animals↗
PubMed1990

Improved detection of oral spirochetes with an anaerobic culture method.

A method for routine culturing of oral spirochetes was studied in periodontitis patients and subjects with healthy gingivae. Subgingival plaque bacteria, including oral spirochetes were cultured anaerobically using the steel wool jar method, the glove-box procedure and the plate-in-bottle method. They were also observed directly with a phase-contrast microscope. The number of colonies of recovered spirochetes was significantly higher with the plate-in-bottle method when Medium 10 (M10) or M10 supplemented with 10% rumen fluid was used. In almost all cases, spirochetes were detected with this culture method. The ratios of spirochetes from patient samples, cultured by the plate-in-bottle method, and of other microorganisms, cultured in Eggerth-Gagnon (EG) medium by the steel wool jar method, were almost identical of those observed by phase-contrast microscopy. These results indicate that it can be just as possible to culture certain oral spirochetes as other anaerobic bacteria.

Bacteriological Techniques↗
PubMed1991

Use of monoclonal antibodies to enumerate spirochetes and identify Treponema denticola in dental plaque of children, adolescents and young adults.

Identification of spirochetes in dental plaque is difficult. Not all spirochetes can be cultured and microscopic analysis based on darkfield or phase optics cannot determine the genus and species of individual bacterial cells. The purpose of this study was to use monoclonal antibodies in an immunoenzyme technique to stain spirochetes in dental plaque. Separate mAb were used to estimate total spirochetes and relative numbers of 2 distinct types of Treponema denticola. Plaque samples were collected from 40 subjects grouped by age. Results showed that older subjects are more likely to have spirochetes, to have more spirochetes and to have more diverse populations or spirochetes than younger subjects. Our studies suggest that T. denticola may be the first treponeme to colonize the primary dentition, that T. denticola appears to comprise a major proportion of all spirochetes at all ages and that two distinct serotypes of T. denticola are found to coexist in plaque from most children.

Adolescent↗
PubMed1993

Observation of an unusually large spirochete in endodontic infection.

Spirochetes in the root canal have been investigated only to a minor extent. Oral spirochetes have been detected particularly in the periodontal pocket, where small, medium-sized and large morphotypes have been reported. In the present darkfield and scanning electron microscopic study we describe a spirochete isolated from the root canal that is 7 times longer (140 microns long) and 5 times thicker (2 microns thick) than usual for treponemes.

Aged↗
PubMed1994

Oral microflora of the ferret at the gingival sulcus and mucosa membrane in relation to ligature-induced periodontitis.

The aim of this study was to describe, in the domestic ferret, the composition of the normal gingival sulcus and the near related mucosa microflora and the shift in the composition during an acute periodontal breakdown induced by the placement of ligatures. Five animals were used. At the start of the experiment (day 0) and before the placement of the ligatures, 2 microbiological samples were obtained from the gingival sulcus and the related mucosa at the mid-buccal surface of the right upper P4. The same sites were sampled on the left side, serving as control sites. On day 28, new microbiological samples were taken from the same 4 sites. The samples were analyzed with darkfield microscopy and with viable counts. In the darkfield analysis, on day 0, the predominant bacterial morphotype was cocci, ranging from 88-92%. The viable counts showed that nearly 100% of the total cultivable flora was composed of facultative anaerobic gram-negative and gram-positive rods. Pasteurella spp., Corynebacterium spp. and Rothia spp. were the major components of these bacterial groups. No anaerobic bacteria were detected. On day 28, cocci decreased to approximately 75% in the experimental gingival sulcus sample, and filaments and rods increased significantly. Spirochetes remained largely unchanged during the experiment. The composition of the experimental site samples changed. There was a decrease in the mean numbers of facultative anaerobic gram-positive rods, and approximately one third of the microflora comprised anaerobic gram-negative rods, mainly Porphyromonas gingivalis and Fusobacterium spp. Although the composition of the microflora of the ferret presented few similarities to that described in dogs and monkeys, the anaerobic portion of the gingival sulcus and oral mucosa microflora related to ligature-induced periodontitis presented microorganisms observed in experimental periodontitis both in dogs and monkeys as well as in human periodontal diseases.

Animals↗
PubMed1997

An inexpensive solid medium for obtaining colony-forming units of oral spirochetes.

A method for the enumeration of colony-forming units of oral anaerobic spirochetes in new oral spirochete agarose (NOS-A) medium was described recently. However, the high cost of agarose limits the extent to which large assays can be carried out. Accordingly, a search for an inexpensive gelling agent that remains molten at 37 degrees C and gels at 25 degrees C was undertaken. Varying amounts of Noble agar or Bacto agar (0.5 to 1.5%, w/v) were mixed with varying amounts of gelatin (0.5 to 1.0%, w/v) in NOS medium. NOS medium containing 0.5% gelatin-0.5% Noble agar (NOS-GN) or 0.5% gelatin-0.5% Bacto agar (NOS-GB) met the above criteria. NOS-GN and NOS-GB media yielded higher colony-forming units with Treponema denticola than NOS-A medium in that order. However, all three media, NOS-GN, NOS-GB and NOS-A, performed equally well in the recovery of viable counts of T. vincentii. The NOS-GN medium was not liquefied by subgingival bacteria or two gelatinase-producing species of bacteria, Bacillus subtilis and Staphylococcus aureus. Thus NOS-GN medium is the recommended medium both in cost and performance for obtaining colony counts of spirochetes.

Bacillus subtilis↗
PubMed2006

Novel subgingival bacterial phylotypes detected using multiple universal polymerase chain reaction primer sets.

INTRODUCTION: Molecular ecological analysis based on 16S rRNA gene sequence analysis is well established for the characterisation of complex bacterial communities. However, 'universal' PCR primers can introduce biases into the analysis of the species composition of clone libraries because of mismatches between the primer and target organism sequences. In this study, three universal primer sets were compared for the analysis of the microflora in subgingival plaque. METHODS: Three subgingival plaque samples were collected from two subjects with localised severe chronic periodontitis. Half of each sample was cultured while DNA was extracted from the remaining half and 16S rDNA amplified with universal primer pairs 27F, 1525R (A); 27F, 1492R (B) and 530F, 1525R (C). Amplified genes were cloned, sequenced and identified by comparison with 16S rRNA databases. RESULTS: 137 taxa were identified among 177 isolates and 417 clones sequenced. Of these, 86 were detected only by the molecular technique whereas 26 were found only by culture. Sequences from 81 taxa did not correspond to those of named species and of these, 38 were not represented in the nucleotide databases. 16S RNA genes for these 38 taxa were sequenced and deposited with GenBank. CONCLUSION: The use of three sets of universal primers allowed the identification of 38 novel bacterial phylotypes. There were marked differences in the composition of the libraries generated by the different primer sets. A combination of molecular and cultural techniques is recommended to maximise the coverage of detection of bacterial taxa in oral samples.

Bacteria↗
PubMed2005

The prevalences of Brachyspira spp. and Lawsonia intracellularis in Swedish piglet producing herds and wild boar population.

The aim of the present study was to survey the prevalences of the enteric pathogens Brachyspira hyodysenteriae, Brachyspira pilosicoli and Lawsonia intracellularis in Swedish growing pigs and in the Swedish wild boar population and to relate these findings to clinical signs. The study included 105 randomly selected herds, constituting approximately one third of Swedish herds with a herd size of >100 sows. The herds were located all over the country. In these herds, growth promoters were not used and pigs sampled were not subjected to any medication. From each herd, samples were taken from 10 growing pigs aged 8-12 weeks, corresponding to approximately 2.5% of all growing pigs present in the herd at the sampling occasion. If possible, the samples were taken from pigs with diarrhoea. Forty-eight faecal samples and 71 rectal swabs were also taken from free-living wild boars (31 piglets, 19 growers and 21 adult animals) at shooting. The samples were analysed by culture and biochemical tests for the presence of Brachyspira spp. and by nested PCR for the presence of L. intracellularis. Brachyspira hyodysenteriae was not demonstrated in any sample. Brachyspira intermedia was detected in 22 samples originating from 15 herds, Brachyspira innocens/Brachyspira murdochii was detected in 370 samples from 82 herds and B. pilosicoli was detected in 134 samples originating from 34 herds. In 21 herds and in 534 samples, no Brachyspira spp. were detected. Lawsonia intracellularis was demonstrated in 285 samples from 50 herds. Further, 418 samples from conventional herds were negative with respect to L. intracellularis and in 345 samples the PCR had been inhibited. All samples from the wild boars were negative for Brachyspira spp., 12 of 48 samples were negative for L. intracellularis, and in 36 wild boar samples, the PCR was inhibited.

Animals↗