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free soluble receptor activator of nuclear factor-kappab ligand in gingival crevicular fluid correlates with distinct pathogens in periodontitis patients.the aim of the experiment was to investigate the levels of free soluble receptor activator of nuclear factor-kb ligand (srankl) in periodontal health and disease and their correlations to clinical parameters and important periodontal pathogens.200818988315
the diverse chec-type phosphatases: chemotaxis and beyond.a new class of protein phosphatases has emerged in the study of bacterial/archaeal chemotaxis, the chec-type phosphatases. these proteins are distinct and unrelated to the well-known chey-p phosphatase chez, though they have convergently evolved to dephosphorylate the same target. the family contains a common consensus sequence d/s-x(3)-e-x(2)-n-x(22)-p that defines the phosphatase active site, of which there are often two per protein. three distinct subgroups make up the family: chec, fliy and ...200818990184
the fusobacterium nucleatum outer membrane protein radd is an arginine-inhibitable adhesin required for inter-species adherence and the structured architecture of multispecies biofilm.a defining characteristic of the suspected periodontal pathogen fusobacterium nucleatum is its ability to adhere to a plethora of oral bacteria. this distinguishing feature is suggested to play an important role in oral biofilm formation and pathogenesis, with fusobacteria proposed to serve as central 'bridging organisms' in the architecture of the oral biofilm bringing together species which would not interact otherwise. previous studies indicate that these bacterial interactions are mediated b ...200919007407
the fusobacterium nucleatum outer membrane protein radd is an arginine-inhibitable adhesin required for inter-species adherence and the structured architecture of multispecies biofilm.a defining characteristic of the suspected periodontal pathogen fusobacterium nucleatum is its ability to adhere to a plethora of oral bacteria. this distinguishing feature is suggested to play an important role in oral biofilm formation and pathogenesis, with fusobacteria proposed to serve as central 'bridging organisms' in the architecture of the oral biofilm bringing together species which would not interact otherwise. previous studies indicate that these bacterial interactions are mediated b ...200919007407
the flat-ribbon configuration of the periplasmic flagella of borrelia burgdorferi and its relationship to motility and morphology.electron cryotomography was used to analyze the structure of the lyme disease spirochete, borrelia burgdorferi. this methodology offers a new means for studying the native architecture of bacteria by eliminating the chemical fixing, dehydration, and staining steps of conventional electron microscopy. using electron cryotomography, we noted that membrane blebs formed at the ends of the cells. these blebs may be precursors to vesicles that are released from cells grown in vivo and in vitro. we fou ...200919011030
the flat-ribbon configuration of the periplasmic flagella of borrelia burgdorferi and its relationship to motility and morphology.electron cryotomography was used to analyze the structure of the lyme disease spirochete, borrelia burgdorferi. this methodology offers a new means for studying the native architecture of bacteria by eliminating the chemical fixing, dehydration, and staining steps of conventional electron microscopy. using electron cryotomography, we noted that membrane blebs formed at the ends of the cells. these blebs may be precursors to vesicles that are released from cells grown in vivo and in vitro. we fou ...200919011030
immune response and alveolar bone resorption in a mouse model of treponema denticola infection.treponema denticola is considered to be an agent strongly associated with periodontal disease. the lack of an animal infection model has hampered the understanding of t. denticola pathogenesis and the host's immune response to infection. in this study, we have established an oral infection model in mice, demonstrating that infection by oral inoculation is feasible. the presence of t. denticola in the oral cavities of the animals was confirmed by pcr. mice given t. denticola developed a specific ...200919015247
detection of helicobacter pylori dna in the saliva of patients complaining of halitosis.helicobacter pylori infection, which causes peptic ulcers and gastric cancer, is considered a possible cause of halitosis. recently, the oral cavity was identified as a possible h. pylori reservoir, particularly in the presence of periodontal disease, which is a cause of halitosis. the purpose of this study was to evaluate by pcr the prevalence of oral h. pylori in the saliva of subjects complaining of halitosis. samples were obtained from 326 non-dyspeptic subjects, comprising 251 subjects with ...200819018029
a bifunctional kinase-phosphatase in bacterial chemotaxis.phosphorylation-based signaling pathways employ dephosphorylation mechanisms for signal termination. histidine to aspartate phosphosignaling in the two-component system that controls bacterial chemotaxis has been studied extensively. rhodobacter sphaeroides has a complex chemosensory pathway with multiple homologues of the escherichia coli chemosensory proteins, although it lacks homologues of known signal-terminating chey-p phosphatases, such as chez, chec, fliy or chex. here, we demonstrate th ...200819020080
transcription and genetic analyses of a putative n-acetylmuramyl-l-alanine amidase in borrelia burgdorferi.in this study, a putative n-acetylmuramyl-l-alanine amidase gene (bb0666) was identified in the genome of the lyme disease spirochete borrelia burgdorferi. this protein shares c. 30% identity with its counterparts from other bacteria. reverse transcriptase-pcr analysis showed that bb0666 along with two other genes (bb0665 and bb0667) are cotranscribed with the motility and chemotaxis genes. this newly identified operon is termed as pami. sequence and primer extension analyses showed that pami wa ...200919025570
transcription and genetic analyses of a putative n-acetylmuramyl-l-alanine amidase in borrelia burgdorferi.in this study, a putative n-acetylmuramyl-l-alanine amidase gene (bb0666) was identified in the genome of the lyme disease spirochete borrelia burgdorferi. this protein shares c. 30% identity with its counterparts from other bacteria. reverse transcriptase-pcr analysis showed that bb0666 along with two other genes (bb0665 and bb0667) are cotranscribed with the motility and chemotaxis genes. this newly identified operon is termed as pami. sequence and primer extension analyses showed that pami wa ...200919025570
[relationship of putative periodontopathogenic bacteria and drug-induced gingival overgrowth].to investigate the effect of putative periodontopathogenic bacteria on the development of drug-induced gingival overgrowth (go) in renal transplant recipients.200819031785
persistence of extracrevicular bacterial reservoirs after treatment of aggressive periodontitis.the purpose of this study was to test the hypothesis that periodontal pathogens associated with aggressive periodontitis persist in extracrevicular locations following scaling and root planing, systemic antibiotics, and antimicrobial rinses.200819053921
coaggregation of treponema denticola with porphyromonas gingivalis and fusobacterium nucleatum is mediated by the major outer sheath protein of treponema denticola.coagreggation of treponema denticola with either porphyromonas gingivalis or fusobacterium nucleatum was characterized and the role of the major outer sheath protein (msp) in the coaggregation process of these bacteria was evaluated. the msp of t. denticola was found to be able to bind to p. gingivalis and f. nucleatum cells and this binding could be inhibited by msp in a concentration-dependent manner. while sodium dodecyl sulfate polyacrylamide gel electrophoresis and periodic acid-schiff (pas ...200819054094
differences in subgingival microflora of korean and german periodontal patients.the goal of this study was to characterize the microbiological profile in samples of subgingival plaque taken from periodontal patients with different ethnic origin.200919058781
hica of escherichia coli defines a novel family of translation-independent mrna interferases in bacteria and archaea.toxin-antitoxin (ta) loci are common in free-living bacteria and archaea. ta loci encode a stable toxin that is neutralized by a metabolically unstable antitoxin. the antitoxin can be either a protein or an antisense rna. so far, six different ta gene families, in which the antitoxins are proteins, have been identified. recently, makarova et al. (k. s. makarova, n. v. grishin, and e. v. koonin, bioinformatics 22:2581-2584, 2006) suggested that the hicab loci constitute a novel ta gene family. us ...200919060138
hica of escherichia coli defines a novel family of translation-independent mrna interferases in bacteria and archaea.toxin-antitoxin (ta) loci are common in free-living bacteria and archaea. ta loci encode a stable toxin that is neutralized by a metabolically unstable antitoxin. the antitoxin can be either a protein or an antisense rna. so far, six different ta gene families, in which the antitoxins are proteins, have been identified. recently, makarova et al. (k. s. makarova, n. v. grishin, and e. v. koonin, bioinformatics 22:2581-2584, 2006) suggested that the hicab loci constitute a novel ta gene family. us ...200919060138
[identification of periodontopathogen microorganisms by pcr technique].periodontitis is an inflammatory disease of the supporting tissues of teeth and is a major cause of tooth loss in adults. the onset and progression of periodontal disease is attributed to the presence of elevated levels of a consortium of pathogenic bacteria. gram negative bacteria, mainly strict anaerobes, play the major role.200819069337
tumor necrosis factor-alpha -308g/a single nucleotide polymorphism and red-complex periodontopathogens are independently associated with increased levels of tumor necrosis factor-alpha in diseased periodontal tissues.inflammatory cytokines such as tumor necrosis factor-alpha are involved in the pathogenesis of periodontal diseases. a high between-subject variation in the level of tumor necrosis factor-alpha mrna has been verified, which may be a result of genetic polymorphisms and/or the presence of periodontopathogens such as porphyromonas gingivalis, tannerella forsythia, treponema denticola (called the red complex) and aggregatibacter actinomycetemcomitans. in this study, we investigated the effect of the ...200919076989
in vitro susceptibility of bovine digital dermatitis associated spirochaetes to antimicrobial agents.bovine digital dermatitis (bdd) is an infectious lameness in cattle, which has a large global impact in terms of animal welfare and cost. the majority of evidence suggests that spirochaetes are the aetiological agent of this disease. the aim of this study was to identify the susceptibility of bdd associated spirochaetes to a range of antimicrobial agents with a view to potential usage in vivo to treat this widespread cattle disease. a microdilution method was adapted to determine the in vitro su ...200919081208
optimizing qpcr for the quantification of periodontal pathogens in a complex plaque biofilm.quantitative pcr (qpcr) has recently been used to quantify microorganisms in complex communities, including dental plaque biofilms. however, there is variability in the qpcr protocols being used. this study was designed to evaluate the validity of two of these variables with the intent of developing a more standardized qpcr protocol. the two variables evaluated were (1) the use of dna content versus actual cell counts to estimate bacterial numbers in mixed plaque samples and (2) the effectivenes ...200819088882
proteolytic activities of oral bacteria on prommp-9 and the effect of synthetic proteinase inhibitors.tissue reactions to bacteria lead to proinflammatory reactions involving matrix metalloproteinases (mmps). synthetic protease inhibitors may offer new possibilities to regulate bacterial proteases. we investigated proteolytic activities of certain periodontal bacteria, their effects on the latent prommp-9, and the effects of synthetic mmp inhibitors and a serine protease inhibitor pefabloc. the strains studied were porphyromonas gingivalis, prevotella intermedia, peptostreptoccus micros, prevote ...200819088890
tobacco use increases susceptibility to bacterial infection.abstract: active smokers and those exposed to secondhand smoke are at increased risk of bacterial infection. tobacco smoke exposure increases susceptibility to respiratory tract infections, including tuberculosis, pneumonia and legionnaires disease; bacterial vaginosis and sexually transmitted diseases, such as chlamydia and gonorrhoea; helicobacter pylori infection; periodontitis; meningitis; otitis media; and post-surgical and nosocomial infections. tobacco smoke compromises the anti-bacterial ...200819094204
identification of a divided genome for vsh-1, the prophage-like gene transfer agent of brachyspira hyodysenteriae.the brachyspira hyodysenteriae b204 genome sequence revealed three vsh-1 tail genes, hvp31, hvp60, and hvp37, in a 3.6-kb cluster. the location and transcription direction of these genes relative to those of the previously described vsh-1 16.3-kb gene operon indicate that the gene transfer agent vsh-1 has a noncontiguous, divided genome.200919103931
identification of a divided genome for vsh-1, the prophage-like gene transfer agent of brachyspira hyodysenteriae.the brachyspira hyodysenteriae b204 genome sequence revealed three vsh-1 tail genes, hvp31, hvp60, and hvp37, in a 3.6-kb cluster. the location and transcription direction of these genes relative to those of the previously described vsh-1 16.3-kb gene operon indicate that the gene transfer agent vsh-1 has a noncontiguous, divided genome.200919103931
porphyromonas gingivalis rgpa-kgp proteinase-adhesin complexes penetrate gingival tissue and induce proinflammatory cytokines or apoptosis in a concentration-dependent manner.the rgpa-kgp proteinase-adhesin complexes of porphyromonas gingivalis were observed, using immunostaining, in human gingival tissue associated with periodontitis but not in healthy tissue. the staining pattern suggested a concentration gradient from the subgingival plaque into the subjacent gingival connective tissue. intense immunostaining was observed in areas displaying gross disturbance of tissue architecture. p. gingivalis cells and the rgpa-kgp complexes at low concentrations were shown to ...200919114547
porphyromonas gingivalis rgpa-kgp proteinase-adhesin complexes penetrate gingival tissue and induce proinflammatory cytokines or apoptosis in a concentration-dependent manner.the rgpa-kgp proteinase-adhesin complexes of porphyromonas gingivalis were observed, using immunostaining, in human gingival tissue associated with periodontitis but not in healthy tissue. the staining pattern suggested a concentration gradient from the subgingival plaque into the subjacent gingival connective tissue. intense immunostaining was observed in areas displaying gross disturbance of tissue architecture. p. gingivalis cells and the rgpa-kgp complexes at low concentrations were shown to ...200919114547
immune evasion of leptospira species by acquisition of human complement regulator c4bp.leptospirosis is a spirochetal zoonotic disease of global distribution with a high incidence in tropical regions. in the last 15 years it has been recognized as an important emerging infectious disease due to the occurrence of large outbreaks in warm-climate countries and, occasionally, in temperate regions. pathogenic leptospires efficiently colonize target organs after penetrating the host. their invasiveness is attributed to the ability to multiply in blood, adhere to host cells, and penetrat ...200919114549
immune evasion of leptospira species by acquisition of human complement regulator c4bp.leptospirosis is a spirochetal zoonotic disease of global distribution with a high incidence in tropical regions. in the last 15 years it has been recognized as an important emerging infectious disease due to the occurrence of large outbreaks in warm-climate countries and, occasionally, in temperate regions. pathogenic leptospires efficiently colonize target organs after penetrating the host. their invasiveness is attributed to the ability to multiply in blood, adhere to host cells, and penetrat ...200919114549
sufa - a bacterial enzyme that cleaves fibrinogen and blocks fibrin network formation.finegoldia magna is a member of the normal human bacterial flora on the skin and other non-sterile body surfaces, but this anaerobic coccus is also an important opportunistic pathogen. sufa was the first f. magna proteinase to be isolated and characterized. many bacterial pathogens interfere with different steps of blood coagulation, and here we describe how purified sufa efficiently and specifically cleaves fibrinogen in human plasma. sufa is both secreted by f. magna and associated with the ba ...200919118364
toll-like receptors 2 and 5 in human gingival epithelial cells co-operate with t-cell cytokine interleukin-17.periodontitis begins as the result of perturbation of the gingival epithelial cells caused by subgingival bacteria interacting with the epithelial cells via pattern recognition receptors. toll-like receptors (tlrs) have been shown to play an important role in the recognition of periodontal pathogens so we have studied the interaction of tlr ligands with tlr2 and tlr5 for cytokine production in the cultures of gingival epithelial cells.200919121068
periodontal pathogen levels in adolescents before, during, and after fixed orthodontic appliance therapy.this purpose of this study was to document and investigate changes in periodontal pathogen levels before, during, and after orthodontic treatment in adolescents.200919121507
short-term clinical and microbiological evaluations of peri-implant diseases before and after mechanical anti-infective therapies.the aim of this study was to evaluate the clinical and microbiological effects of mechanical anti-infective therapies for mucositis and peri-implantitis.200919126114
analysis of a band 7/mec-2 family gene of porphyromonas gingivalis.in vivo-induced antigen technology has previously been used to identify 115 genes induced in porphyromonas gingivalis w83 during human infection. the aim of this study was to determine if one of these genes, pg1334, was important for the virulence of p. gingivalis. analysis of plaque samples from persons with periodontitis revealed that pg1334 was expressed in 88.0% of diseased sites, compared with 42.1% of healthy sites, even though p. gingivalis was detected in equal numbers from both sites. a ...200919131314
microbiology of odontogenic bacteremia: beyond endocarditis.summary: the human gingival niche is a unique microbial habitat. in this habitat, biofilm organisms exist in harmony, attached to either enamel or cemental surfaces of the tooth as well as to the crevicular epithelium, subjacent to a rich vascular plexus underneath. due to this extraordinary anatomical juxtaposition, plaque biofilm bacteria have a ready portal of ingress into the systemic circulation in both health and disease. yet the frequency, magnitude, and etiology of bacteremias due to ora ...200919136433
association of unique, isolated treponemes with bovine digital dermatitis lesions.this study used a pcr-based approach targeting 16s rrna gene fragments to determine the occurrence and association of the three bovine digital dermatitis (bdd) treponeme phylogroups within lesions found in cattle from the united kingdom. examination of 51 bdd lesions collected from infected cattle across the united kingdom revealed that bdd treponeme group 1 (treponema medium/treponema vincentii-like), group 2 (treponema phagedenis-like), and group 3 (treponema putidum/treponema denticola-like) ...200919144804
the vaginal microflora in relation to gingivitis.gingivitis has been linked to adverse pregnancy outcome (apo). bacterial vaginosis (bv) has been associated with apo. we assessed if bacterial counts in bv is associated with gingivitis suggesting a systemic infectious susceptibilty.200919161595
porphyromonas gingivalis with either tannerella forsythia or treponema denticola induces synergistic il-6 production by murine macrophage-like j774.1 cells.chronic periodontitis is caused by mixed bacterial infection. porphyromonas gingivalis, tannerella forsythia and treponema denticola are frequently detected in deep periodontal pockets. we demonstrate that these bacteria induce proinflammatory cytokine production by the mouse macrophage-like cell line j774.1.200919162208
salivary detection of periodontopathic bacteria and periodontal health status in dental students.saliva may become a potential source of contamination through vertical and horizontal transmissions as well as cross-infections. this study aims to use saliva as a screening tool to detect putative periodontal pathogens in a young population with fairly good oral hygiene.200919162209
auranofin disrupts selenium metabolism in clostridium difficile by forming a stable au-se adduct.clostridium difficile is a nosocomial pathogen whose incidence and importance are on the rise. previous work in our laboratory characterized the central role of selenoenzyme-dependent stickland reactions in c. difficile metabolism. in this work we have identified, using mass spectrometry, a stable complex formed upon reaction of auranofin (a gold-containing drug) with selenide in vitro. x-ray absorption spectroscopy supports the structure that we proposed on the basis of mass-spectrometric data. ...200919165513
tobacco-induced alterations to porphyromonas gingivalis-host interactions.smokers are more susceptible than non-smokers to persistent infection by porphyromonas gingivalis, a causative agent of periodontitis. patients who smoke exhibit increased susceptibility to periodontitis and are more likely to display severe disease and be refractory to treatment. paradoxically, smokers demonstrate reduced clinical inflammation. we show that p. gingivalis cells exposed to cigarette smoke extract (cse) induce a lower proinflammatory response (tumour necrosis factor-alpha, interle ...200919175666
tannerella forsythia and the hla-dqb1 allele are associated with susceptibility to periodontal disease in japanese adolescents.periodontal disease is a multiple factor disease caused by genetic factors, environmental factors, and periodontal bacteria (periodontal pathogens). the present study aimed to elucidate the risk factors for periodontal disease in japanese adolescents. subjects (11-16 years old) were classified into three groups: localized aggressive periodontitis (lap), periodontal attachment loss (pal), and periodontally healthy (ph) groups. genomic dna isolated from the buccal mucosa was used for single-nucleo ...200919184295
design and activity of a 'dual-targeted' antimicrobial peptide.numerous reports have indicated the important role of human normal flora in the prevention of microbial pathogenesis and disease. evidence suggests that infections at mucosal surfaces result from the outgrowth of subpopulations or clusters within a microbial community and are not linked to one pathogenic organism alone. to preserve the protective normal flora whilst treating the majority of infective bacteria in the community, a tuneable therapeutic is necessary that can discriminate between ben ...200919188046
rickettsia phylogenomics: unwinding the intricacies of obligate intracellular life.completed genome sequences are rapidly increasing for rickettsia, obligate intracellular alpha-proteobacteria responsible for various human diseases, including epidemic typhus and rocky mountain spotted fever. in light of phylogeny, the establishment of orthologous groups (ogs) of open reading frames (orfs) will distinguish the core rickettsial genes and other group specific genes (class 1 ogs or c1ogs) from those distributed indiscriminately throughout the rickettsial tree (class 2 og or c2ogs) ...200819194535
the effect of diode laser (980 nm) treatment on aggressive periodontitis: evaluation of microbial and clinical parameters.the aim was to compare the effect of scaling and root planing (srp) alone, diode laser treatment (las) alone, and srp combined with las (srp + las) on clinical and microbial parameters in patients with aggressive periodontitis.200919196111
analysis of a unique interaction between the complement regulatory protein factor h and the periodontal pathogen treponema denticola.treponema denticola, a spirochete associated with periodontitis, is abundant at the leading edge of subgingival plaque, where it interacts with gingival epithelia. t. denticola produces a number of virulence factors, including dentilisin, a protease which is cytopathic to host cells, and fhbb, a unique t. denticola lipoprotein that binds complement regulatory proteins. earlier analyses suggested that fhbb specifically bound to factor h (fh)-like protein 1 (fhl-1). however, by using dentilisin-de ...200919204088
identification of spirochetes associated with contagious ovine digital dermatitis.spirochetes of the genus treponema were cultured from 7 of 10 cases of digital dermatitis in sheep. two cultures comprised treponema phagedenis-like and treponema medium/treponema vincentii-like spirochetes, respectively, while the remaining cultures comprised mixed populations of treponema medium/treponema vincentii-like, treponema phagedenis-like, and treponema denticola/treponema putidum-like organisms.200919204100
hand instrumentation versus ultrasonic debridement in the treatment of chronic periodontitis: a randomized clinical and microbiological trial.to compare the effectiveness of scaling and root planing (srp) with the use of hand instruments to that of non-surgical treatment with the use of an ultrasonic device, using clinical and microbiological criteria.200919207889
[detection of 3 anaerobic microorganisms in saliva and subgingival plaque of patients with periodontitis].to investigate the prevalence of 3 anaerobic microorganisms including porphyromonas gingivalis (pg), tannerella forsythia (tf) and treponema denticola (td) in saliva and pooled subgingival plaque of different types of periodontitis and compare the detections of three microorganisms between saliva and pooled subgingival plaque sample from the same patient, and analyze the relationship between prevalence of these pathogens in saliva and periodontal parameters.200919221563
does pregnancy have an impact on the subgingival microbiota?we investigated clinical and subgingival microbiologic changes during pregnancy in 20 consecutive pregnant women > or =18 years not receiving dental care.200919228092
bacterial profiles of oral streptococcal and periodontal bacterial species in saliva specimens from japanese subjects.recent developments in molecular biological techniques have increased understanding of the distribution of oral bacterial species in clinical specimens, though few investigations have been conducted to simultaneously detect oral streptococcal and periodontal species in the same specimens. the purpose of the present study was to investigate the distribution and correlation of 6 oral streptococcal and 6 periodontal species in saliva specimens taken from children and their mothers.200919230860
effects of oral commensal and pathogenic bacteria on human dendritic cells.the oral cavity harbors a diverse and complex microbial community. bacteria accumulate on both the hard and soft oral tissues in sessile biofilms and engage the host in an intricate cellular dialog, which normally constrains the bacteria to a state of commensal harmony. dendritic cells (dcs) are likely to balance tolerance and active immunity to commensal microorganisms as part of chronic inflammatory responses. while the role played by dcs in maintaining intestinal homeostasis has been investig ...200919239635
interpain a, a cysteine proteinase from prevotella intermedia, inhibits complement by degrading complement factor c3.periodontitis is an inflammatory disease of the supporting structures of the teeth caused by, among other pathogens, prevotella intermedia. many strains of p. intermedia are resistant to killing by the human complement system, which is present at up to 70% of serum concentration in gingival crevicular fluid. incubation of human serum with recombinant cysteine protease of p. intermedia (interpain a) resulted in a drastic decrease in bactericidal activity of the serum. furthermore, a clinical stra ...200919247445
identification of pathogen and host-response markers correlated with periodontal disease.periodontitis is the major cause of tooth loss in adults and is linked to systemic illnesses, such as cardiovascular disease and stroke. the development of rapid point-of-care (poc) chairside diagnostics has the potential for the early detection of periodontal infection and progression to identify incipient disease and reduce health care costs. however, validation of effective diagnostics requires the identification and verification of biomarkers correlated with disease progression. this clinica ...200919254128
diversity of spirochetes in endodontic infections.the diversity of spirochetes in primary endodontic infections of teeth with chronic apical periodontitis or acute apical abscesses was investigated using 16s rrna gene clone library analysis. the prevalences of three common cultivable oral treponema species were also determined using species-specific nested pcr. all detected spirochetes belonged to the genus treponema. overall, 28 different taxa were identified from the 431 clones sequenced: 9 cultivable and validly named species, 1 cultivable a ...200919261792
genome sequence of the pathogenic intestinal spirochete brachyspira hyodysenteriae reveals adaptations to its lifestyle in the porcine large intestine.brachyspira hyodysenteriae is an anaerobic intestinal spirochete that colonizes the large intestine of pigs and causes swine dysentery, a disease of significant economic importance. the genome sequence of b. hyodysenteriae strain wa1 was determined, making it the first representative of the genus brachyspira to be sequenced, and the seventeenth spirochete genome to be reported. the genome consisted of a circular 3,000,694 base pair (bp) chromosome, and a 35,940 bp circular plasmid that has not p ...200919262690
rapid and accurate diagnosis of human intestinal spirochetosis by fluorescence in situ hybridization.human intestinal spirochetosis (his) is associated with overgrowth of the large intestine by spirochetes of the genus brachyspira. the microbiological diagnosis of his is hampered by the fastidious nature and slow growth of brachyspira spp. in clinical practice, his is diagnosed histopathologically, and a significant portion of cases may be missed. fluorescence in situ hybridization (fish) is a molecular method that allows the visualization and identification of single bacteria within tissue sec ...200919279178
fusobacterium nucleatum atcc 10953 requires actinomyces naeslundii atcc 43146 for growth on saliva in a three-species community that includes streptococcus oralis 34.formation of dental plaque is a developmental process involving initial and late colonizing species that form polymicrobial communities. fusobacteria are the most numerous gram-negative bacteria in dental plaque, but they become prevalent after the initial commensal colonizers, such as streptococci and actinomyces, have established communities. the unusual ability of these bacteria to coaggregate with commensals, as well as pathogenic late colonizers, has been proposed to facilitate colonization ...200919286780
a review of dental implants and infection.dental implants have become increasingly common for the management of tooth loss. despite their placement in a contaminated surgical field, success rates are relatively high. this article reviews dental implants and highlights factors leading to infection and potential implant failure. a literature search identified studies analysing the microbial composition of peri-implant infections. the microflora of dental peri-implantitis resembles that found in chronic periodontitis, featuring predominant ...200919329223
diversity and morphology of members of the phylum "synergistetes" in periodontal health and disease.members of the phylum "synergistetes" have frequently been detected in the human oral cavity at sites of dental disease, but they have rarely been detected in studies of oral health. only two oral "synergistetes" taxa are cultivable. the aims of this study were to investigate the diversity of "synergistetes" in the oral cavity, to establish whether "synergistetes" taxa are more strongly associated with periodontitis than with oral health, and to visualize unculturable "synergistetes" in situ. si ...200919346352
porphyromonas gingivalis-host interactions: open war or intelligent guerilla tactics?this review summarizes and discusses virulence mechanisms whereby porphyromonas gingivalis can persist in the oral cavity. it is proposed that the virulence of p. gingivalis is dependent, at least in part, upon its ability to establish a complex host-pathogen molecular crosstalk which subverts innate immunity. the sophisticated stealth and sabotage tactics used by p. gingivalis may additionally benefit co-habiting organisms occupying the same niche.200919348960
inhibition of selenium metabolism in the oral pathogen treponema denticola.in this report we provide evidence that the antimicrobial action of stannous salts and a gold drug, auranofin, against treponema denticola is mediated through inhibition of the metabolism of selenium for synthesis of selenoproteins.200919363113
oral infectious diseases: a potential risk factor for hiv virus recrudescence?as the highly active antiretroviral therapy (haart) has transitioned human immunodeficiency virus (hiv) infection into a 'chronic disease' management strategy, there is growing evidence that infection with non-hiv pathogens in hiv+ patients may have important public health implications in undermining haart success and acquired immunodeficiency syndrome progression. several bacterial and host cell products during infections with non-hiv pathogens have shown the capacity to regulate hiv replicatio ...200919364391
red bacterial complex is associated with the severity of chronic periodontitis in a thai population.the distribution of periodontal pathogens differs in various geographic locations and racial/ethnic groups. this study investigated the microbiological features of chronic periodontitis (cp) patients in thailand.200919371397
diversity and site-specificity of the oral microflora in the elderly.the purpose of the present study was to describe the bacterial diversity in the oral cavity of the elderly without root caries using bacterial microarrays, and to determine the site- and subject-specificity of bacterial colonization. samples were collected from the tongue dorsum, mucosa of the buccal fold, hard palate, supragingival plaque from sound root surfaces, and subgingival plaque from the same roots. a new 16 s rrna gene-based microarray method was used for the simultaneous detection of ...200919373498
coaggregation by the freshwater bacterium sphingomonas natatoria alters dual-species biofilm formation.coaggregation is hypothesized to enhance freshwater biofilm development. to investigate this hypothesis, the ability of the coaggregating bacterium sphingomonas natatoria to form single- and dual-species biofilms was studied and compared to that of a naturally occurring spontaneous coaggregation-deficient variant. attachment assays using metabolically inactive cells were performed using epifluorescence and confocal laser scanning microscopy. under static and flowing conditions, coaggregating s. ...200919376917
are putative periodontal pathogens reliable diagnostic markers?periodontitis is one of the most common chronic inflammatory diseases. a number of putative bacterial pathogens have been associated with the disease and are used as diagnostic markers. in the present study, we compared the prevalence of oral bacterial species in the subgingival biofilm of generalized aggressive periodontitis (gap) (n = 44) and chronic periodontitis (cp) (n = 46) patients with that of a periodontitis-resistant control group (pr) (n = 21). the control group consisted of subjects ...200919386852
the oxyr homologue in tannerella forsythia regulates expression of oxidative stress responses and biofilm formation.tannerella forsythia is an anaerobic periodontal pathogen that encounters constant oxidative stress in the human oral cavity due to exposure to air and reactive oxidative species from coexisting dental plaque bacteria as well as leukocytes. in this study, we sought to characterize a t. forsythia orf with close similarity to bacterial oxidative stress response sensor protein oxyr. to analyse the role of this oxyr homologue, a gene deletion mutant was constructed and characterized. aerotolerance, ...200919389765
borrelia burgdorferi reva antigen binds host fibronectin.borrelia burgdorferi, the lyme disease-causing spirochete, can persistently infect its vertebrate hosts for years. b. burgdorferi is often found associated with host connective tissue, where it interacts with components of the extracellular matrix, including fibronectin. some years ago, a borrelial surface protein, named bbk32, was identified as a fibronectin-binding protein. however, b. burgdorferi bbk32 mutants are still able to bind fibronectin, indicating that the spirochete possesses additi ...200919398540
pyramidobacter piscolens gen. nov., sp. nov., a member of the phylum 'synergistetes' isolated from the human oral cavity.four strains of anaerobic, gram-negative bacilli isolated from the human oral cavity were subjected to a comprehensive range of phenotypic and genotypic tests and were found to comprise a homogeneous group distinct from any species with validly published names. 16s rrna and 23s rrna gene sequence analyses and dna-dna reassociation data revealed that the strains constituted a novel group within the phylum 'synergistetes' and were most closely related to jonquetella anthropi. two libraries of rand ...200919406777
the microbiota on different oral surfaces in healthy children.knowledge of the early oral colonization patterns could provide a better understanding of oral biofilm development and disease initiation that in turn could be the basis for early preventive programmes.200919416446
role of aggregatibacter actinomycetemcomitans in glutathione catabolism.our previous studies demonstrated that three enzymes, gamma-glutamyltransferase (ggt), cysteinylglycinase (cgase) and cystalysin, are required for the catabolism of glutathione to produce hydrogen sulfide (h(2)s) in treponema denticola. in this study, we examined glutathione catabolism in aggregatibacter actinomycetemcomitans.200919416454
detection of treponema denticola in symptomatic apical periodontitis and in symptomatic apical abscesses by real-time pcr.the aim of this study was to investigate the presence of treponema denticola in symptomatic apical periodontitis and in symptomatic apical abscesses by real-time polymerase chain reaction (pcr) method.200919421390
heterogeneity of systemic inflammatory responses to periodontal therapy.we investigated the effect of comprehensive periodontal therapy on the levels of multiple systemic inflammatory biomarkers.200919426174
bacteria in the apical root canal of teeth with primary apical periodontitis.bacteria settled in the apical root canal are in a privileged position to inflict damage to the periradicular tissues. therefore, the species identified in this region can be of special relevance for the pathogenesis of apical periodontitis. this study investigated the occurrence and levels of several bacterial taxa in the apical root canal of teeth with apical periodontitis.200919426923
intact flagellar motor of borrelia burgdorferi revealed by cryo-electron tomography: evidence for stator ring curvature and rotor/c-ring assembly flexion.the bacterial flagellar motor is a remarkable nanomachine that provides motility through flagellar rotation. prior structural studies have revealed the stunning complexity of the purified rotor and c-ring assemblies from flagellar motors. in this study, we used high-throughput cryo-electron tomography and image analysis of intact borrelia burgdorferi to produce a three-dimensional (3-d) model of the in situ flagellar motor without imposing rotational symmetry. structural details of b. burgdorfer ...200919429612
[markers of periodontal diseases and sensitivity to taromentine in patients with aggressive periodontitis].the aim of the research was to study sensitivity of specific microorganisms from the periodontal pockets of patients with rapidly progressive periodontal disease to taromentine. 95 patients aged 21 to 35 years (50 women (52,6+/-33,62) and 45 men (47,36+/-3,62)) with rapidly progressive form of periodontal desease were observed. porphiromonas gingivalis was identifide in 83 out of 95 patients (87,36+/-2,06). prevotella intermedia - in 31 patients (32,6+/-2,750); actinobacillus actinomycetemcomita ...200919430039
the use of perioscan as a potential screening test for mothers at risk for delivery of pre-term and low birth-weight infants.increased levels of oestrogen and progesterone during pregnancy may lead to periodontal disease. the anaerobic gram-negative bacteria classified as the "red complex" (porphyromonas gingivalis, tannerella forsythia and treponema denticola) are frequently associated with periodontal disease. periodontopathogens produce toxins and enzymes that can enter the bloodstream and cross the placenta to harm the foetus. the response of the mother's immune system to infection by these periodontopathogens bri ...200919431959
treponema pallidum, the stealth pathogen, changes, but how?treponema pallidum rapidly disseminates from a genital site of inoculation to diverse organs where it establishes persistent infection. t. pallidum has long been regarded as a stealth pathogen because of its poorly antigenic and non-inflammatory surface. there is now increasing evidence that antigenic variation also contributes to the ability of the spirochaete to evade host defences. among the small number of proteins encoded by the t. pallidum genome with sequence similarity to well-characteri ...200919432802
tp0262 is a modulator of promoter activity of tpr subfamily ii genes of treponema pallidum ssp. pallidum.transcriptional regulation in treponema pallidum ssp. pallidum is poorly understood, primarily because this organism cannot be cultivated in vitro or genetically manipulated. we have recently shown a phase variation mechanism controlling transcription initiation of subfamily ii tpr (t. pallidumrepeat) genes (tpre, tprg and tprj), a group of virulence factor candidates. furthermore, the same study suggested that additional mechanisms might influence the level of transcription of these tprs. the t ...200919432808
the oral microbial consortium's interaction with the periodontal innate defense system.the oral microbial consortium is the most characterized polymicrobial microbial community associated with the human host. extensive sampling of both microbial and tissue samples has demonstrated that there is a strong association between the type of microbial community found in the gingival crevice and the status of innate host mediator expression. the strong clinical association between the microbial community and the innate host response in both clinically healthy and diseased tissue suggests ...200919435427
microbial changes in periodontitis successfully treated by mechanical plaque removal and systemic amoxicillin and metronidazole.scaling and root planing in conjunction with systemic administration of antibiotics is used for treatment of aggressive periodontitis. the study investigated the changes of the subgingival microbiota in a homogeneous cohort of 12 female caucasian patients. plaque samples were obtained from 4 defined deep lesions per patient at baseline and 2, 6, and 12 months after therapy (mechanical plaque removal, oral administration of amoxicillin and metronidazole). amplification of the 16s rrna gene, cloni ...200919447073
distinct roles of long/short fimbriae and gingipains in homotypic biofilm development by porphyromonas gingivalis.porphyromonas gingivalis, a periodontal pathogen, expresses a number of virulence factors, including long (fima) and short (mfa) fimbriae as well as gingipains comprised of arginine-specific (rgp) and lysine-specific (kgp) cysteine proteinases. the aim of this study was to examine the roles of these components in homotypic biofilm development by p. gingivalis, as well as in accumulation of exopolysaccharide in biofilms.200919470157
systemic immune responses in pregnancy and periodontitis: relationship to pregnancy outcomes in the obstetrics and periodontal therapy (opt) study.our previous studies reported on the obstetric, periodontal, and microbiologic outcomes of women participating in the obstetrics and periodontal therapy (opt) study. this article describes the systemic antibody responses to selected periodontal bacteria in the same patients.200919485826
major proteins and antigens of treponema denticola.treponema denticola is a gram-negative, motile, asaccharolytic, anaerobic spirochaete which along with porphyromonas gingivalis and tannerella forsythia has been shown to form a bacterial consortium called the red complex that is strongly associated with the clinical progression of chronic periodontitis. t. denticola was grown in continuous culture in a complex medium with a mean generation time of 15.75 h. samples from two different membrane-enriched preparations and a cytoplasm-enriched prepar ...200919501677
clinical effectiveness of photodynamic therapy in the treatment of periodontitis.a randomized-controlled clinical pilot trial was designed to evaluate photodynamic therapy (pdt) for its bactericidal potential and clinical effect in the treatment of periodontitis.200919554711
comparison between polymerase chain reaction-based and checkerboard dna hybridization techniques for microbial assessment of subgingival plaque samples.to compare polymerase chain reaction (pcr) with subsequent reverse hybridization (micro-ident test) and checkerboard dna-dna hybridization for the identification of 13 bacterial species in subgingival plaque samples.200919563330
the influence of tobacco smoking on the onset of periodontitis in young persons.abstract : this paper reviews the evidence for cigarette smoking as a risk factor for the development of severe destructive periodontal disease in young adults. a high prevalence of cigarette smoking has been identified among young individuals with aggressive periodontitis and tobacco usage increases the risk of periodontal destruction most significantly in young populations. the effect appears to be dose related and is independent of levels of plaque accumulation. young smokers have more alveol ...200419570272
proteomic analysis of endodontic infections by liquid chromatography-tandem mass spectrometry.endodontic infections are very prevalent and have a polymicrobial etiology characterized by complex interrelationships between endodontic microorganisms and the host defenses. proteomic analysis of endodontic infections can provide global insights into the invasion, pathogenicity mechanisms, and multifactorial interactions existing between root canal bacteria and the host in the initiation and progression of apical periodontitis. the purpose of this study was to apply proteomic techniques such a ...200919572900
plasminogen acquisition and activation at the surface of leptospira species lead to fibronectin degradation.pathogenic leptospira species are the etiological agents of leptospirosis, a widespread disease of human and veterinary concern. in this study, we report that leptospira species are capable of binding plasminogen (plg) in vitro. the binding to the leptospiral surface was demonstrated by indirect immunofluorescence confocal microscopy with living bacteria. the plg binding to the bacteria seems to occur via lysine residues because the ligation is inhibited by addition of the lysine analog 6-aminoc ...200919581392
egfrviii and c-met pathway inhibitors synergize against pten-null/egfrviii+ glioblastoma xenografts.receptor tyrosine kinase (rtk) systems, such as hepatocyte growth factor (hgf) and its receptor c-met, and epidermal growth factor receptor (egfr), are responsible for the malignant progression of multiple solid tumors. recent research shows that these rtk systems comodulate overlapping and dynamically adaptable oncogenic downstream signaling pathways. this study investigates how egfrviii, a constitutively active egfr deletion mutant, alters tumor growth and signaling responses to rtk inhibition ...200919584231
detection and quantification of five major periodontal pathogens by single copy gene-based real-time pcr.periodontitis is a common chronic multibacterial infection in the tooth-supporting tissues. it has been shown that periodontitis patients carry higher number of disease-associated bacteria than healthy ones. the aim of this study was to generate a novel, single copy gene-based quantitative real-time pcr (qpcr) assay for five major periodontal pathogens - aggregatibacter actinomycetemcomitans, porphyromonas gingivalis, prevotella intermedia, treponema denticola, and tannerella forsythia. the prim ...200919586997
is obesity an oral bacterial disease?the world-wide explosion of overweight people has been called an epidemic. the inflammatory nature of obesity is widely recognized. could it really be an epidemic involving an infectious agent? in this climate of concern over the increasing prevalence of overweight conditions in our society, we focus on the possible role of oral bacteria as a potential direct contributor to obesity. to investigate this possibility, we measured salivary bacterial populations of overweight women. saliva was collec ...200919587155
involvement of toll-like receptors 2 and 4 in the innate immune response to treponema denticola and its outer sheath components.treponema denticola is considered an important oral pathogen in the development and progression of periodontal diseases. in the present study, the mechanisms of recognition and activation of murine macrophages by t. denticola and its major outer sheath protein (msp) and lipooligosaccharide (los or glycolipid) were investigated. t. denticola cells and the msp induced innate immune responses through tlr2-myd88, whereas los induced a macrophage response through tlr4-myd88. the presence of gamma int ...200919596768
a novel murine model for chronic inflammatory alveolar bone loss.chronic inflammatory bowel disease (ibd) demonstrates some similarities to the dysregulated chronic immunoinflammatory lesion of periodontitis. trinitrobenzene sulphonic acid (tnbs) and dextran sodium sulphate (dss) administered to rodents have been shown to elicit inflammatory responses that undermine the integrity of the gut epithelium in a similar manner to ibd in humans. the objective of this study was to evaluate the ability of these chemicals to elicit periodontal inflammation as a novel m ...201019602109
a novel murine model for chronic inflammatory alveolar bone loss.chronic inflammatory bowel disease (ibd) demonstrates some similarities to the dysregulated chronic immunoinflammatory lesion of periodontitis. trinitrobenzene sulphonic acid (tnbs) and dextran sodium sulphate (dss) administered to rodents have been shown to elicit inflammatory responses that undermine the integrity of the gut epithelium in a similar manner to ibd in humans. the objective of this study was to evaluate the ability of these chemicals to elicit periodontal inflammation as a novel m ...201019602109
hydrogen sulfide induces apoptosis in human periodontium cells.the existence of hydrogen sulfide (h(2)s) at high concentrations in periodontal pockets is a characteristic feature of periodontitis. periodontal pathogens play a key role in the production of h(2)s under these etiology conditions. this study was designed to examine the cytotoxicity of h(2)s in periodontium cells, including human periodontal ligament (pdl) cells and human gingival fibroblasts (hgfs), as well as the role of h(2)s in apoptosis induction.201019602114
characterizing traditionally defined periodontal disease in hiv+ adults.results have varied from previous studies examining the level and extent of periodontal disease (pd) in hiv-1 infected (hiv+) adults. these studies used different methodologies to measure and define pd and examined cohorts with divergent characteristics. inconsistent methodological approaches may have resulted in the underestimation of traditionally-defined pd in hiv+ individuals.200919624697
microbiological profile of untreated subjects with localized aggressive periodontitis.the microbial profile of localized aggressive periodontitis (lagp) has not yet been determined. therefore, the aim of this study was to evaluate the subgingival microbial composition of lagp.200919637996
microbiological risk for periodontitis of abutment teeth in patients with removable partial dentures.tannerella forsythia, porphyromonas gingivalis and treponema denticola are identified as the red complex which exists in high proportions in periodontally diseased patients. the aim of this study was to assess the microbiological risk for periodontitis of abutment teeth in subjects wearing removable partial dentures (rpds) by measuring the red complex using bana-zymetm test. thirty-eight subjects (mean age: 62.2 years) with kennedy class ii partially edentulous arch participated in this study. t ...200919650858
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