Publications

clinical and microbiological evaluation of the effectiveness of the nd:yap laser for the initial treatment of adult periodontitis. a randomized controlled study.	enhancement of the results obtained by scaling and planing is most often sought by using antimicrobial therapies. laser beams have been shown to be bactericidal and could possibly target pathogens more effectively and with fewer compliance problems than antiseptic solutions.	2005	15882229
strain relief at the active site of phosphoserine aminotransferase induced by radiation damage.	the x-ray susceptibility of the lysine-pyridoxal-5'-phosphate schiff base in bacillus alcalophilus phosphoserine aminotransferase has been investigated using crystallographic data collected at 100 k to 1.3 a resolution, complemented by on-line spectroscopic studies. x-rays induce deprotonation of the internal aldimine, changes in the schiff base conformation, displacement of the cofactor molecule, and disruption of the schiff base linkage between pyridoxal-5'-phosphate and the lys residue. analy ...	2005	15883191
prostaglandin e(2) is a main mediator in receptor activator of nuclear factor-kappab ligand-dependent osteoclastogenesis induced by porphyromonas gingivalis, treponema denticola, and treponema socranskii.	periodontitis is an inflammatory disease that often leads to destruction of alveolar bone; a number of bacteria in subgingival plaque are associated with bone destruction in periodontitis. to understand the mechanism of how periodontopathogens induce osteoclastogenesis, we determined which mediators are involved in the osteoclastogenesis.	2005	15898943
debridement and local application of tetracycline in the management of persistent periodontitis. clinical and microbiological results after 12 months.	the purpose of this study was to evaluate the clinical and microbiological efficacy of local delivery of tetracycline in persistent periodontal lesions after topical therapy.	2005	15902062
immunological evaluation and cellular location analysis of the tpri antigen of treponema pallidum subsp. pallidum.	the tpri antigen of treponema pallidum subsp. pallidum is a putative virulence factor predicted to be located in the outer membrane of the syphilis spirochete. in this study, we analyzed the immune response against tpri and its subunits in sera collected both from rabbits experimentally infected with the nichols strain and from patients with syphilis, showing a different pattern of reactivity toward the antigen in these two groups of samples. the protective ability of recombinant tpri and its hy ...	2005	15908421
protein-protein interactions in the chemotaxis signalling pathway of treponema denticola.	motile bacteria employ sophisticated chemotaxis signal transduction systems to transform environmental cues into corresponding behavioural responses. the proteins involved in this signalling pathway have been extensively studied on a molecular level in various model organisms, including enterobacteria and bacillus subtilis, and specific protein-protein interactions have been identified. the chemotaxis operon of spirochaetes encodes a novel chemotaxis protein, chex, in addition to homologues to t ...	2005	15941989
microarrays complement culture methods for identification of bacteria in endodontic infections.	the aim of this study was to investigate the microbial composition of necrotic root canals using culture methods and microarray technology. twenty uniradicular teeth with radiographic evidence of periapical bone loss and with no previous endodontic treatment were selected for this study. for molecular diagnosis a dna chip with 20 different species-specific, 16s-rdna-directed catcher probes was used. the microorganisms most frequently detected by the dna chip were: micromonas micros, fusobacteriu ...	2005	15943771
the tetr family of transcriptional repressors.	we have developed a general profile for the proteins of the tetr family of repressors. the stretch that best defines the profile of this family is made up of 47 amino acid residues that correspond to the helix-turn-helix dna binding motif and adjacent regions in the three-dimensional structures of tetr, qacr, cprb, and ethr, four family members for which the function and three-dimensional structure are known. we have detected a set of 2,353 nonredundant proteins belonging to this family by scree ...	2005	15944459
a census of membrane-bound and intracellular signal transduction proteins in bacteria: bacterial iq, extroverts and introverts.	analysis of complete microbial genomes showed that intracellular parasites and other microorganisms that inhabit stable ecological niches encode relatively primitive signaling systems, whereas environmental microorganisms typically have sophisticated systems of environmental sensing and signal transduction.	2005	15955239
use of the genomic subtractive hybridization technique to develop a real-time pcr assay for quantitative detection of prevotella spp. in oral biofilm samples.	genomic subtractive hybridization was used to design prevotella nigrescens-specific primers and taqman probes. based on this technique, a taqman real-time pcr assay was developed for quantifying four oral black-pigmented prevotella species. the combination of real-time pcr and genomic subtractive hybridization is useful for preparing species-specific primer-probe sets for closely related species.	2005	15956428
signature proteins that are distinctive of alpha proteobacteria.	the alpha (alpha) proteobacteria, a very large and diverse group, are presently characterized solely on the basis of 16s rrna trees, with no known molecular characteristic that is unique to this group. the genomes of three alpha-proteobacteria, rickettsia prowazekii (rp), caulobacter crescentus (cc) and bartonella quintana (bq), were analyzed in order to search for proteins that are unique to this group.	2005	15960851
predictive value of clinical and microbiological parameters for the treatment outcome of scaling and root planing.	to compare the clinical and microbiological outcome of non-surgical periodontal therapy after 6 months with data obtained after hygienic phase or 6 weeks after completion of non-surgical therapy, in order to evaluate the value of clinical and microbiological parameters to predict treatment success.	2005	15966873
association between coinfection of porphyromonas gingivalis, actinobacillus actinomycetemcomitans and treponema denticola and periodontal tissue destruction in chronic periodontitis.	the association between the infection of porphyromonas gingivalis, actinobacillus actinomycetemcomitans and treponema denticola in chronic periodontitis (cp) and the severity of periodontal disease remains to be elucidated. the aim of this study was to investigate the subgingival infection frequencies of three periodontopathic bacteria in chinese cp patients and to evaluate the correlations between infection by these bacteria and periodontal destruction.	2005	15978192
the bioinformatics resource for oral pathogens.	complete genomic sequences of several oral pathogens have been deciphered and multiple sources of independently annotated data are available for the same genomes. different gene identification schemes and functional annotation methods used in these databases present a challenge for cross-referencing and the efficient use of the data. the bioinformatics resource for oral pathogens (brop) aims to integrate bioinformatics data from multiple sources for easy comparison, analysis and data-mining thro ...	2005	15980574
periodontal disease and coronary heart disease: a reappraisal of the exposure.	results from studies relating periodontal disease to cardiovascular disease have been mixed. residual confounding by smoking and use of clinical measures of periodontal disease rather than measures of infection have been 2 major criticisms. the aims of this study were to investigate relationships between prevalent coronary heart disease (chd) and 2 exposures, (1) clinical periodontal disease and (2) igg antibodies to 17 oral organisms, and to evaluate the role of smoking in these relationships.	2005	15983248
the salivary microbiota as a diagnostic indicator of oral cancer: a descriptive, non-randomized study of cancer-free and oral squamous cell carcinoma subjects.	the purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (oscc) lesion would differ from those found in cancer-free (oscc-free) controls.	2005	15987522
a leptospira interrogans enzyme with similarity to yeast ste14p that methylates the 1-phosphate group of lipid a.	distinct from other spirochetes, cells of leptospira interrogans contain orthologues of all the escherichia coli lpx genes required for lipid a biosynthesis, but they synthesize a modified form of lipopolysaccharide that supposedly activates toll-like receptor 2 (tlr2) instead of tlr4. the recent determination of the l. interrogans lipid a structure revealed an unprecedented o-methylation of its 1-phosphate group (que-gewirth, n. l. s., ribeiro, a. a., kalb, s. r., cotter, r. j., bulach, d. m., ...	2005	15994324
prevalence of putative periodontopathogens in subgingival dental plaques from gingivitis lesions in korean orthodontic patients.	the objective of this study was to detect and compare the presence of periodontopathogens in the subgingival plaques of gingivitis lesions in adults who wore fixed orthodontic appliances, as opposed to adults who did not wear any orthodontic appliances. thirty-six individuals participated in this study. nineteen of these subjects did not wear any orthodontic appliances, and these subjects comprised the control group. the other 17 individuals had been wearing fixed orthodontic appliances for at l ...	2005	15995644
uncultivated phylotypes and newly named species associated with primary and persistent endodontic infections.	endodontic infections have been traditionally studied by culture methods, but recent reports showing that over 50% of the oral microbiota is still uncultivable (b. j. paster et al., j. bacteriol. 183:3770-3783, 2001) raise the possibility that many endodontic pathogens remain unknown. this study intended to investigate the prevalence of several uncultivated oral phylotypes, as well as newly named species in primary or persistent endodontic infections associated with chronic periradicular disease ...	2005	16000454
oral bacteria in the occluded arteries of patients with buerger disease.	recent studies have suggested that infectious organisms play a role in vascular diseases. in this study, to explore a possible link between oral infection and buerger disease, we investigated whether oral (periodontal) bacteria were present in occluded arteries removed from patients with characteristic buerger disease.	2005	16012459
origin and evolution of the archaeo-eukaryotic primase superfamily and related palm-domain proteins: structural insights and new members.	we report an in-depth computational study of the protein sequences and structures of the superfamily of archaeo-eukaryotic primases (aeps). this analysis greatly expands the range of diversity of the aeps and reveals the unique active site shared by all members of this superfamily. in particular, it is shown that eukaryotic nucleo-cytoplasmic large dna viruses, including poxviruses, asfarviruses, iridoviruses, phycodnaviruses and the mimivirus, encode aeps of a distinct family, which also includ ...	2005	16027112
selective capture of salmonella enterica serovar typhi genes expressed in macrophages that are absent from the salmonella enterica serovar typhimurium genome.	thirty-six salmonella enterica serovar typhi-specific genes, absent from the salmonella enterica serovar typhimurium genome, that were expressed in human macrophages were identified by selective capture of transcribed sequences. these genes are located on 15 unique loci of the serovar typhi genome, including salmonella pathogenicity islands (spi-7, spi-8, and spi-10) and bacteriophages (st15, st18, and st35).	2005	16041043
the leptospira interrogans lexa gene is not autoregulated.	footprinting and mutagenesis experiments demonstrated that leptospira interrogans lexa binds the palindrome tttgn(5)caaa found in the reca promoter but not in the lexa promoter. in silico analysis revealed that none of the other canonical sos genes is under direct control of lexa, making the leptospiral lexa gene the first described which is not autoregulated.	2005	16077133
identification of candidate periodontal pathogens and beneficial species by quantitative 16s clonal analysis.	most studies of the bacterial etiology of periodontitis have used either culture-based or targeted dna approaches, and so it is likely that pathogens remain undiscovered. the purpose of this study was to use culture-independent, quantitative analysis of biofilms associated with chronic periodontitis and periodontal health to identify pathogens and beneficial species. samples from subjects with periodontitis and controls were analyzed using ribosomal 16s cloning and sequencing. several genera, ma ...	2005	16081935
synergistic biofilm formation by treponema denticola and porphyromonas gingivalis.	biofilm formation is an important step in the etiology of periodontal diseases. in this study, in vitro biofilm formation by treponema denticola and porphyromonas gingivalis 381 displayed synergistic effects. confocal microscopy demonstrated that p. gingivalis attaches to the substratum first as a primary colonizer followed by coaggregation with t. denticola to form a mixed biofilm. the t. denticola flagella mutant as well as the cytoplasmic filament mutant were shown to be essential for biofilm ...	2005	16085371
detection of bacteria in endodontic samples by polymerase chain reaction assays and association with defined clinical signs in italian patients.	the presence of selected bacteria (enterococcus faecalis, porphyromonas gingivalis, prevotella intermedia, tannerella forsythensis, treponema denticola) in infected root canals was studied using polymerase chain reaction (pcr) assays, and the association of bacteria with clinical signs of endodontic disease was assessed. the null hypothesis, that no difference could be observed between clinical signs of apical periodontitis and a specific bacterial strain, was tested.	2005	16101964
impact of smoking on the clinical, microbiological and immunological parameters of adult patients with periodontitis.	the aim of the current study was to assess the impact of smoking on the clinical indices, the humoral immune response and the detection frequency of putative periodontal pathogens in patients with periodontitis cross-sectionally and following therapy.	2005	16104962
identification of genes of vsh-1, a prophage-like gene transfer agent of brachyspira hyodysenteriae.	vsh-1 is a mitomycin c-inducible prophage of the anaerobic spirochete brachyspira hyodysenteriae. purified vsh-1 virions are noninfectious, contain random 7.5-kb fragments of the bacterial genome, and mediate generalized transduction of b. hyodysenteriae cells. in order to identify and sequence genes of this novel gene transfer agent (gta), proteins associated either with vsh-1 capsids or with tails were purified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. the n-terminal amino ...	2005	16109929
gene organization and transcriptional analysis of the tprj, tpri, tprg, and tprf loci in treponema pallidum strains nichols and sea 81-4.	the tpr gene family of treponema pallidum subsp. pallidum, the causative agent of syphilis, has recently become the focus of intensive investigation. tprf and tpri sequences are highly conserved among different isolates and are the targets of strong humoral and cellular immune responses of the host, and immunization with a recombinant peptide from the amino terminus of these antigens has been shown to alter significantly lesion development following homologous challenge. this indicates that thes ...	2005	16109950
horizontally acquired genes for purine salvage in borrelia spp. causing relapsing fever.	unlike borrelia burgdorferi, the relapsing fever agent borrelia hermsii and the related borrelia miyamotoi had pura and purb genes of the purine salvage pathway. these were located among the rrna genes. phylogenetic analysis indicated that these genes had a different evolutionary history than those of orthologs in other spirochetes.	2005	16113341
discrimination of streptococcus pneumoniae from viridans group streptococci by genomic subtractive hybridization.	two oligonucleotide primer sets for the discrimination of streptococcus pneumoniae from "pneumococcus-like" oral streptococcal isolates by pcr were developed. genomic subtractive hybridization was performed to search for differences between streptococcus pneumoniae strain wu2 and the most closely related oral streptococcus, streptococcus mitis strain 903. we identified 19 clones that contained s. pneumoniae-specific nucleotide fragments that were absent from the chromosomal dna of typical labora ...	2005	16145102
amylomaltase of pyrobaculum aerophilum im2 produces thermoreversible starch gels.	amylomaltases are 4-alpha-glucanotransferases (ec 2.4.1.25) of glycoside hydrolase family 77 that transfer alpha-1,4-linked glucans to another acceptor, which can be the 4-oh group of an alpha-1,4-linked glucan or glucose. the amylomaltase-encoding gene (pae1209) from the hyperthermophilic archaeon pyrobaculum aerophilum im2 was cloned and expressed in escherichia coli, and the gene product (pyamase) was characterized. pyamase displays optimal activity at ph 6.7 and 95 degrees c and is the most ...	2005	16151092
molecular detection of treponema denticola and porphyromonas gingivalis in carotid and aortic atheromatous plaques by fish: report of two cases.	treponema denticola and porphyromonas gingivalis have been identified in atheromatous plaques of two patients suffering from atherosclerosis by pcr and fluorescence in situ hybridization (fish). the use of the fish technique suggested that these periodontopathic micro-organisms might be metabolically active within the wall of arteries, under the atherosclerotic lesion.	2005	15591262
enzyme adaptation to alkaline ph: atomic resolution (1.08 a) structure of phosphoserine aminotransferase from bacillus alcalophilus.	the crystal structure of the vitamin b(6)-dependent enzyme phosphoserine aminotransferase from the obligatory alkaliphile bacillus alcalophilus has been determined at 1.08 a resolution. the model was refined to an r-factor of 11.7% (r(free) = 13.9%). the enzyme displays a narrow ph optimum of enzymatic activity at ph 9.0. the final structure was compared to the previously reported structure of the mesophilic phosphoserine aminotransferase from escherichia coli and to that of phosphoserine aminot ...	2005	15608117
upregulation of intercellular adhesion molecule 1 and proinflammatory cytokines by the major surface proteins of treponema maltophilum and treponema lecithinolyticum, the phylogenetic group iv oral spirochetes associated with periodontitis and endodontic infections.	treponema maltophilum and treponema lecithinolyticum belong to the group iv oral spirochetes and are associated with endodontic infections, as well as periodontitis. recently, the genes encoding the major surface proteins (msps) of these bacteria (mspa and msptl, respectively) were cloned and sequenced. the amino acid sequences of these proteins showed significant similarity. in this study we analyzed the functional role of these homologous proteins in human monocytic thp-1 cells and primary cul ...	2005	15618163
the cytolethal distending toxin induces receptor activator of nf-kappab ligand expression in human gingival fibroblasts and periodontal ligament cells.	actinobacillus actinomycetemcomitans is associated with localized aggressive periodontitis, a disease characterized by rapid loss of the alveolar bone surrounding the teeth. receptor activator of nf-kappab ligand (rankl) and osteoprotegerin (opg) are two molecules that regulate osteoclast formation and bone resorption. rankl induces osteoclast differentiation and activation, whereas opg blocks this process by acting as a decoy receptor for rankl. the purpose of this study was to investigate the ...	2005	15618171
biochemical characterization of phosphoryl transfer involving hpr of the phosphoenolpyruvate-dependent phosphotransferase system in treponema denticola, an organism that lacks pts permeases.	treponema pallidum and treponema denticola encode within their genomes homologues of energy coupling and regulatory proteins of the phosphoenolpyruvate:sugar phosphotransferase system (pts) but no recognizable homologues of pts permeases. these homologues include (1) enzyme i, (2) hpr, (3) two iia(ntr)-like proteins, and (4) hpr(ser) kinase/phosphorylase (hprk). because the enzyme i-encoding gene in t. pallidum is an inactive pseudogene and because all other pts genes in both t. pallidum and t. ...	2005	15641785
clinical effects of scaling and root planing on untreated teeth.	the aim of this report is to examine whether scaling and root planing (srp) in one area of the mouth may affect periodontal improvement in untreated areas in the same patient, possibly through systemic effects of treatment.	2005	15642054
quantitative analysis of multi-species oral biofilms by taqman real-time pcr.	oral infectious diseases, including dental caries, various forms of periodontitis and oral malodor, are not caused by a single pathogen. the etiology of these diseases is known to be associated with bacterial accumulation and plaque composition on the hard and soft tissues of the oral cavity. therefore, the quantitative, as well as qualitative, analysis of the microorganisms present in oral biofilms, namely dental plaque, subgingival plaque and tongue debris, is important for diagnosis and ratio ...	2005	16160072
homologues of insecticidal toxin complex genes in yersinia enterocolitica biotype 1a and their contribution to virulence.	yersinia enterocolitica is an enteric pathogen that consists of six biotypes: 1a, 1b, 2, 3, 4, and 5. strains of the latter five biotypes can carry a virulence plasmid, known as pyv, and several well-characterized chromosomally encoded virulence determinants. y. enterocolitica strains of biotype 1a lack the virulence-associated markers of pyv-bearing strains and were once considered to be avirulent. there is growing epidemiological, clinical, and experimental evidence, however, to suggest that s ...	2005	16177365
evaluation of liaison treponema screen, a novel recombinant antigen-based chemiluminescence immunoassay for laboratory diagnosis of syphilis.	the purpose of this study was to evaluate the diagnostic performance of liaison treponema screen (diasorin, saluggia, italy), a new automated chemiluminescence immunoassay (clia), in comparison with that of rapid plasma reagin (rpr) and the following currently used treponemal tests: hemagglutination test (tpha), immunoenzymatic assay (eia), and western blot (wb). first, a retrospective study was performed with a panel of 2,494 blood donor sera, a panel of 131 clinical and serologically character ...	2005	16210488
probing the role of tyr 64 of treponema denticola cystalysin by site-directed mutagenesis and kinetic studies.	tyr 64, hydrogen-bonded to coenzyme phosphate in treponema denticola cystalysin, was changed to alanine by site-directed mutagenesis. spectroscopic and kinetic properties of the tyr 64 mutant were investigated in an effort to explore the differences in coenzyme structure and kinetic mechanism relative to those of the wild-type enzyme. the wild type displays coenzyme absorbance bands at 418 and 320 nm, previously attributed to ketoenamine and substituted aldamine, respectively. the tyr 64 mutant ...	2005	16229486
demonstration of factor h-like protein 1 binding to treponema denticola, a pathogen associated with periodontal disease in humans.	treponema denticola is an important contributor to periodontal disease. in this study we investigated the ability of t. denticola to bind the complement regulatory proteins factor h and factor h-like protein 1 (fhl-1). the binding of these proteins has been demonstrated to facilitate evasion of the alternative complement cascade and/or to play a role in adherence and invasion. here we demonstrate that t. denticola specifically binds fhl-1 via a 14-kda, surface-exposed protein that we designated ...	2005	16239506
defining the interaction of the treponema pallidum adhesin tp0751 with laminin.	various invasive pathogens attach to host tissues via the extracellular matrix component laminin, the major glycoprotein found within basement membranes. previous investigations identified the laminin-binding adhesin tp0751 within the spirochete bacterium treponema pallidum. in the current study, tp0751 was shown to attach to a variety of laminin isoforms that are widely distributed throughout the host, including laminins 1, 2, 4, 8, and 10. such universal attachment is conducive for an adhesin ...	2005	16239550
treponema denticola infection is not a cause of false positive treponema pallidum serology.	it has long been assumed that parodontal disease can be a cause of false positive results in syphilis serology, but so far there are no definitive data supporting this hypothesis. in this study we tested 250 serum samples obtained from blood donors. all of them were negative when routinely screened for antibodies against treponema pallidum. then, all these samples were tested by immunoenzymatic (elisa) and western blot (wb) assays to investigate reactivities against t. denticola. thirteen sample ...	2005	16240693
dissimilatory metabolism of nitrogen oxides in bacteria: comparative reconstruction of transcriptional networks.	bacterial response to nitric oxide (no) is of major importance since no is an obligatory intermediate of the nitrogen cycle. transcriptional regulation of the dissimilatory nitric oxides metabolism in bacteria is diverse and involves fnr-like transcription factors hcpr, dnr, and nnrr; two-component systems narxl and narqp; no-responsive activator norr; and nitrite-sensitive repressor nsrr. using comparative genomics approaches, we predict dna-binding motifs for these transcriptional factors and ...	2005	16261196
defining the normal bacterial flora of the oral cavity.	more than 700 bacterial species or phylotypes, of which over 50% have not been cultivated, have been detected in the oral cavity. our purposes were (i) to utilize culture-independent molecular techniques to extend our knowledge on the breadth of bacterial diversity in the healthy human oral cavity, including not-yet-cultivated bacteria species, and (ii) to determine the site and subject specificity of bacterial colonization. nine sites from five clinically healthy subjects were analyzed. sites i ...	2005	16272510
biofilm formation by the periodontopathic bacteria treponema denticola and porphyromonas gingivalis.	periodontitis develops as a result of the interaction of the host with subgingival plaque bacteria. both porphyromonas gingivalis and treponema denticola are frequently associated together in these oral biofilms.	2005	16277575
involvement of periodontopathic anaerobes in aspiration pneumonia.	increasing evidence has linked the anaerobic bacteria forming periodontopathic biofilms with aspiration pneumonia in elderly persons. in experiments designed to eliminate the potent respiratory pathogens forming biofilms in the oral cavity, we have shown that the mechanical and chemical oral cleansing using povidone-iodine effectively reduced the detection rates and numbers of methicillin-sensitive staphylococcus species, streptococcus pneumoniae, and haemophilus influenzae in patients scheduled ...	2005	16277588
chex is a phosphorylated chey phosphatase essential for borrelia burgdorferi chemotaxis.	motility and chemotaxis are believed to be important in the pathogenesis of lyme disease caused by the spirochete borrelia burgdorferi. controlling the phosphorylation state of chey, a response regulator protein, is essential for regulating bacterial chemotaxis and motility. rapid dephosphorylation of phosphorylated chey (chey-p) is crucial for cells to respond to environmental changes. chey-p dephosphorylation is accomplished by one or more phosphatases in different species, including chez, che ...	2005	16291669
streptococci dominate the diverse flora within buccal cells.	previously, we reported that intracellular actinobacillus actinomycetemcomitans, porphyromonas gingivalis, and tannerella forsythensis were present within buccal epithelial cells from human subjects, as lesser components of a polymicrobial flora. in this study, we further characterized that intracellular flora by using the same double-labeling techniques to identify fusobacterium nucleatum, prevotella intermedia, oral campylobacter species, eikenella corrodens, treponema denticola, gemella haemo ...	2005	16304448
evaluation of gel-pad oligonucleotide microarray technology by using artificial neural networks.	past studies have suggested that thermal dissociation analysis of nucleic acids hybridized to dna microarrays would improve discrimination among duplex types by scanning through a broad range of stringency conditions. to more fully constrain the utility of this approach using a previously described gel-pad microarray format, artificial neural networks (nns) were trained to recognize noisy or low-quality data, as might derive from nonspecific fluorescence, poor hybridization, or compromised data ...	2005	16332861
identification and localization of extraradicular biofilm-forming bacteria associated with refractory endodontic pathogens.	bacterial biofilms have been found to develop on root surfaces outside the apical foramen and be associated with refractory periapical periodontitis. however, it is unknown which bacterial species form extraradicular biofilms. the present study aimed to investigate the identity and localization of bacteria in human extraradicular biofilms. twenty extraradicular biofilms, used to identify bacteria using a pcr-based 16s rrna gene assay, and seven root-tips, used to observe immunohistochemical loca ...	2005	16332869
[experience in medical ozone use for root canal treatment].	the results of clinical and laboratory assessment of effectiveness of psr-diagnosis are presented. the high efficacy of ozone therapy is revealed. the findings demonstrate the reduction of number in the micro-organisms in root canal: actinobacillus actinomycetemcomitans from 31.25% to 10.21%; bacteriodes forsythus from 68.75% to 15.50%; treponema denticola from 37.5% to 11.4%; porphyromonas gingivalis from 56.25% to 45%; prevotella intermedia from 16% to 0%.	2005	16353031
laboratory maintenance of treponema denticola.	this unit describes the methods, media, and equipment necessary for routine laboratory culture and handling of the anaerobic oral spirochete treponema denticola. topics discussed include nutrient requirements, recommended media formulations, and expected growth kinetics, as well as methods and equipment necessary to maintain anaerobic conditions. an additional protocol on isolation of t. denticola from clinical samples is included.	2005	18770551
genetic manipulation of treponema denticola.	the oral anaerobic spirochete, treponema denticola, has been implicated in the etiology of human periodontal diseases; however, the molecular basis for the virulence of these organisms is still unclear. potential pathogenic factors expressed by t. denticola have recently begun to be identified through the development of gene transfer approaches in this organism following electroporetic transformation. several antibiotic resistance markers have been developed for use in the construction of monosp ...	2005	18770552
infection frequency of epstein-barr virus in subgingival samples from patients with different periodontal status and its correlation with clinical parameters.	to detect the infection frequencies of different genotypes of epstein-barr virus (ebv) in subgingival samples from chronic periodontitis (cp) patients, and to discuss the correlation between infection with ebv and clinical parameters.	2006	17048301
prevalence of selected bacterial named species and uncultivated phylotypes in endodontic abscesses from two geographic locations.	evidence is mounting that the prevalence of some putative endodontic pathogens can significantly vary according to the geographic location in which samples were taken. this study aimed to provide additional knowledge on this subject by comparing the frequencies of 10 selected candidate endodontic pathogens in samples of acute apical abscesses obtained from two distinct geographic locations; portland, or, and rio de janeiro, brazil. dna was extracted from aspirates and used as template in nested ...	2006	17174667
the essential nature of sphingolipids in plants as revealed by the functional identification and characterization of the arabidopsis lcb1 subunit of serine palmitoyltransferase.	serine palmitoyltransferase (spt) catalyzes the first step of sphingolipid biosynthesis. in yeast and mammalian cells, spt is a heterodimer that consists of lcb1 and lcb2 subunits, which together form the active site of this enzyme. we show that the predicted gene for arabidopsis thaliana lcb1 encodes a genuine subunit of spt that rescues the sphingolipid long-chain base auxotrophy of saccharomyces cerevisiae spt mutants when coexpressed with arabidopsis lcb2. in addition, homozygous t-dna inser ...	2006	17194770
characterization, distribution, and expression of novel genes among eight clinical isolates of streptococcus pneumoniae.	eight low-passage-number streptococcus pneumoniae clinical isolates, each of a different serotype and a different multilocus sequence type, were obtained from pediatric participants in a pneumococcal vaccine trial. comparative genomic analyses were performed with these strains and two s. pneumoniae reference strains. individual genomic libraries were constructed for each of the eight clinical isolates, with an average insert size of approximately 1 kb. a total of 73,728 clones were picked for ar ...	2006	16368987
fusobacterium nucleatum transports noninvasive streptococcus cristatus into human epithelial cells.	analysis of human buccal epithelial cells frequently reveals an intracellular polymicrobial consortium of bacteria. although several oral bacteria have been demonstrated to invade cultured epithelial cells, several others appear unable to internalize. we hypothesized that normally noninvasive bacteria may gain entry into epithelial cells via adhesion to invasive bacteria. fusobacterium nucleatum is capable of binding to and invading oral epithelial cells. by contrast, streptococcus cristatus bin ...	2006	16369022
lipoprotein computational prediction in spirochaetal genomes.	lipoproteins are of great interest in understanding the molecular pathogenesis of spirochaetes. because spirochaete lipobox sequences exhibit more plasticity than those of other bacteria, application of existing prediction algorithms to emerging sequence data has been problematic. in this paper a novel lipoprotein prediction algorithm is described, designated splip, constructed as a hybrid of a lipobox weight matrix approach supplemented by a set of lipoprotein signal peptide rules allowing for ...	2006	16385121
relationship of periodontal bacteria and porphyromonas gingivalis fima variations with phenytoin-induced gingival overgrowth.	we investigated the relationship between phenytoin-induced gingival overgrowth (go) and the harboring of periodontal bacteria.	2006	16390469
[microbiological study on the prognosis of immediate implant and periodontal disease].	the aim of the present study was to investigate the prevalence of periodontal marker organisms and specific interleukin-1 (il-1) gene polymorphisms (which show a close association with periodontitis) and their effect on the success of immediate implant placement postextraction in the patient with periodontal disease.	2006	16395549
recovery and evolutionary analysis of complete integron gene cassette arrays from vibrio.	integrons are genetic elements capable of the acquisition, rearrangement and expression of genes contained in gene cassettes. gene cassettes generally consist of a promoterless gene associated with a recombination site known as a 59-base element (59-be). multiple insertion events can lead to the assembly of large integron-associated cassette arrays. the most striking examples are found in vibrio, where such cassette arrays are widespread and can range from 30 kb to 150 kb. besides those found in ...	2006	16417647
biological basis for syphilis.	syphilis is a chronic sexually transmitted disease caused by treponema pallidum subsp. pallidum. clinical manifestations separate the disease into stages; late stages of disease are now uncommon compared to the preantibiotic era. t. pallidum has an unusually small genome and lacks genes that encode many metabolic functions and classical virulence factors. the organism is extremely sensitive to environmental conditions and has not been continuously cultivated in vitro. nonetheless, t. pallidum is ...	2006	16418521
regulation and physiologic significance of the agmatine deiminase system of streptococcus mutans ua159.	we previously demonstrated that streptococcus mutans expresses a functional agmatine deiminase system (agds) encoded by the agmatine-inducible agubdac operon (a. r. griswold, y. y. chen, and r. a. burne, j. bacteriol. 186:1902-1904, 2004). the agds yields ammonia, co2, and atp while converting agmatine to putrescine and is proposed to augment the acid resistance properties and pathogenic potential of s. mutans. to initiate a study of agu gene regulation, the agub transcription initiation site wa ...	2006	16428386
function and evolution of plasmid-borne genes for pyrimidine biosynthesis in borrelia spp.	the thyx gene for thymidylate synthase of the lyme borreliosis (lb) agent borrelia burgdorferi is located in a 54-kb linear plasmid. in the present study, we identified an orthologous thymidylate synthase gene in the relapsing fever (rf) agent borrelia hermsii, located it in a 180-kb linear plasmid, and demonstrated its expression. the functions of the b. hermsii and b. burgdorferi thyx gene products were evaluated both in vivo, by complementation of a thymidylate synthase-deficient escherichia ...	2006	16428394
the transmission of anaerobic periodontopathic organisms.	the oral microbial flora is unique, and available evidence indicates that it is passed vertically from parents to children. in this investigation, we used a chairside assay for the n-benzoyl-dl-arginine-2-naphthylamide (bana)-sensitive enzyme found in porphyromonas gingivalis, treponema denticola, and tannerella forsythensis, to determine the prevalence of these bana-positive species in young children and their caregivers. we predicted that if the bana enzyme was found in plaque samples of child ...	2006	16434739
the metabolism of cholesterol and certain hormonal steroids by treponema denticola.	the aim was to investigate whether reference cultures and fresh isolates of treponema denticola are able to 5alpha-reduce and further metabolise testosterone, 4-androstenedione, progesterone, corticosterone, cortisol or cholesterol. two reference and five freshly isolated cultures of t. denticola were incubated with either radiolabeled or unlabeled steroid substrates; in the first case products were identified by thin layer chromatography and in the latter by gas chromatography-mass spectroscopy ...	2006	16436288
supportive periodontal therapy using mechanical instrumentation or 2% minocycline gel: a 12 month randomized, controlled, single masked pilot study.	to compare the short-term performance of subgingival local delivery of 2% minocycline gel and conventional subgingival debridement in supportive periodontal therapy (spt) patients.	2006	16441740
comparison of bacterial plaque samples from titanium implant and tooth surfaces by different methods.	studies have shown similarities in the microflora between titanium implants or tooth sites when samples are taken by gingival crevicular fluid (gcf) sampling methods. the purpose of the present study was to study the microflora from curette and gcf samples using the checkerboard dna-dna hybridization method to assess the microflora of patients who had at least one oral osseo-integrated implant and who were otherwise dentate. plaque samples were taken from tooth/implant surfaces and from sulcular ...	2006	16441779
early colonization of non-submerged dental implants in patients with a history of advanced aggressive periodontitis.	the aim of the study was to evaluate the early colonization of non-submerged implants over a 6-month period in partially edentulous patients treated for advanced aggressive periodontal disease. in 22 patients treated for advanced aggressive periodontitis and in a supportive maintenance program for a period between 12 and 240 months at implant surgery, a total of 68 non-submerged dental implants were installed. patients had a plaque score below 20%, and less than 20% of the pockets around the tee ...	2006	16441780
inhibition of periodontopathogen-derived proteolytic enzymes by a high-molecular-weight fraction isolated from cranberry.	porphyromonas gingivalis, tannerella forsythia and treponema denticola are three major aetiological agents of chronic periodontitis. the strong proteolytic activities of these bacteria are critical to their survival since their energy source is obtained from peptides and amino acids derived from proteins. in addition, proteases are important factors contributing to periodontal tissue destruction by a variety of mechanisms, including direct tissue degradation and modulation of host inflammatory r ...	2006	16473919
brucella abortus synthesizes phosphatidylcholine from choline provided by the host.	the brucella cell envelope is characterized by the presence of phosphatidylcholine (pc), a common phospholipid in eukaryotes that is rare in prokaryotes. studies on the composition of brucella abortus 2308 phospholipids revealed that the synthesis of pc depends on the presence of choline in the culture medium, suggesting that the methylation biosynthetic pathway is not functional. phospholipid composition of pmta and pcs mutants indicated that in brucella, pc synthesis occurs exclusively via the ...	2006	16484204
is pre-term labour associated with periodontitis in a danish maternity ward?	to reveal differences in periodontal status and presence of subgingival bacteria in a scandinavian population of women with pre-term birth compared with women who delivered at term.	2006	16489943
modulation of human neutrophil functions in vitro by treponema denticola major outer sheath protein.	in this study of human polymorphonuclear leukocytes (pmns), pretreatment with treponema denticola major outer sheath protein (msp) inhibited formyl-methionyl-leucyl-phenylalanine (fmlp)-induced chemotaxis, phagocytosis of immunoglobulin g-coated microspheres, fmlp-stimulated calcium transients, and actin assembly. msp neither altered oxidative responses to phorbol myristate or fmlp nor induced apoptosis. msp selectively impairs chemotaxis and phagocytosis by impacting the pmn cytoskeleton.	2006	16495573
selective binding of borrelia burgdorferi ospe paralogs to factor h and serum proteins from diverse animals: possible expansion of the role of ospe in lyme disease pathogenesis.	the binding of borrelia burgdorferi ospe, ospf, and family 163 (elp) proteins to factor h/factor h-like protein 1 (fhl-1) and other serum proteins from different animals was assessed. ospe paralogs bound factor h and unidentified serum proteins from a subset of animals, while ospf and elp proteins did not. these data advance our understanding of factor h binding, the host range of the lyme spirochetes, and the expanding role of ospe in pathogenesis.	2006	16495576
anti-inflammatory activity of a high-molecular-weight cranberry fraction on macrophages stimulated by lipopolysaccharides from periodontopathogens.	periodontitis is a chronic inflammatory disease affecting oral tissues. the continuous, high production of cytokines by host cells triggered by periodontopathogens is thought to be responsible for the destruction of tooth-supporting tissues. macrophages play a critical role in this host inflammatory response to periodontopathogens. the aim of this study was to investigate the effect of non-dialyzable material prepared from cranberry juice concentrate on the pro-inflammatory cytokine response of ...	2006	16498070
description of the subgingival microbiota of periodontally untreated mexican subjects: chronic periodontitis and periodontal health.	recent studies have suggested that changes in the prevalence and/or proportion of distinct microorganisms characterize the subgingival microbial profiles of populations around the world. at present, no information is available on the subgingival microbiota of mexican subjects. the purpose of the present study was to determine the microbial composition of subgingival plaque in mexican subjects with untreated chronic periodontitis.	2006	16512761
detection of bacterial dna in atheromatous plaques by quantitative pcr.	this is the first study to analyze atheromatous plaques for the presence of bacterial dna from ten species, including periodontal species and chlamydia pneumoniae. we examined 129 samples of dna extracted from atheromas from 29 individuals for the presence of bacterial 16s rdna sequences from ten different species: porphyromonas gingivalis, actinobacillus actinomycetemcomitans (a.a.), tannerella forsythensis, eikenella corrodens, prevotella intermedia, staphylococcus aureus, staphylococcus epide ...	2006	16513386
periodontal infections and coronary heart disease: role of periodontal bacteria and importance of total pathogen burden in the coronary event and periodontal disease (corodont) study.	chronic inflammation from any source is associated with increased cardiovascular risk. periodontitis is a possible trigger of chronic inflammation. we investigated the possible association between periodontitis and coronary heart disease (chd), focusing on microbiological aspects.	2006	16534043
identification of a homozygous deletion in the ap3b1 gene causing hermansky-pudlak syndrome, type 2.	we report on the molecular etiology of an unusual clinical phenotype associating congenital neutropenia, thrombocytopenia, developmental delay, and hypopigmentation. using genetic linkage analysis and targeted gene sequencing, we defined a homozygous genomic deletion in ap3b1, the gene encoding the beta chain of the adaptor protein-3 (ap-3) complex. the mutation leads to in-frame skipping of exon 15 and thus perturbs proper assembly of the heterotetrameric ap-3 complex. consequently, trafficking ...	2006	16537806
molecular analyses of the interaction of borrelia hermsii fhba with the complement regulatory proteins factor h and factor h-like protein 1.	borrelia hermsii, the primary etiological agent of tick-borne relapsing fever in north america, binds the complement regulatory protein factor h (fh) as a means of evading opsonophagocytosis and the alternative complement pathway. the ability of fh-binding protein a (fhba) to bind fh-like protein 1 (fhl-1) has not been assessed previously. in this study, using a whole-cell absorption assay, we demonstrated that b. hermsii absorbs both fh and fhl-1 from human serum. consistent with this, affinity ...	2006	16552029
exposure of lymphocytes to high doses of actinobacillus actinomycetemcomitans cytolethal distending toxin induces rapid onset of apoptosis-mediated dna fragmentation.	we have shown previously that treatment of human lymphocytes with the actinobacillus actinomycetemcomitans cytolethal distending toxin (cdt) results in dose-dependent g2 arrest, followed 24 h later by apoptotic cell death. here we demonstrated that for jurkat cells exposed to high concentrations of cdt (>0.2 ng/ml) there was a dose-dependent increase in the level of s-phase cells and a concomitant decrease in the level of g2 cells. fluorescence-activated cell sorter analysis demonstrated that th ...	2006	16552037
topical h2 antagonist prevents periodontitis in a rabbit model.	cimetidine is a powerful h2 receptor antagonist that eliminates histamine's effects on chemotaxis, phagocytosis, and superoxide anion production by phagocytes. the purpose of this study was to analyze the clinical and histopathological changes associated with experimental periodontitis in rabbits in response to topically applied cimetidine. experimental periodontitis was induced in 21 new zealand white rabbits using porphyromonas gingivalis (10(9) cfu) topically applied three times a week for a ...	2006	16552070
the treponema denticola surface protease dentilisin degrades interleukin-1 beta (il-1 beta), il-6, and tumor necrosis factor alpha.	dentilisin is a major surface protease and virulence factor of the bacterium treponema denticola. in this study, we found that t. denticola reduced inflammatory cytokines, including interleukin-1beta (il-1beta), il-6, and tumor necrosis factor alpha, in peripheral blood mononuclear cells through degradation by dentilisin.	2006	16552080
clinical and microbiological effects of different antimicrobials on generalized aggressive periodontitis.	to evaluate and compare the effects of adjunctive metronidazole plus amoxicillin, doxycycline and metronidazole on clinical and microbiological parameters in patients with generalized aggressive periodontitis.	2006	16553634
protease-activated receptor-2 activation: a major role in the pathogenesis of porphyromonas gingivalis infection.	we have investigated the specific contribution of protease-activated receptor-2 (par(2)) to host defense during porphyromonas gingivalis infection. culture supernatants from p. gingivalis strains 33277 and w50 provoked ca(2+) mobilization in cells transfected with par(2) (par(2)-knrk) and desensitized the subsequent responses to par(2)-selective agonist. in addition, culture supernatants of p. gingivalis e8 (rgpa/rgpb double knockout) did not cause calcium response in par(2)-knrk cells, evidenci ...	2006	16565494
subgingival and tongue microbiota during early periodontitis.	periodontal infections have a microbial etiology. association of species with early disease would be useful in determining which microbes initiate periodontitis. we hypothesized that the microbiota of subgingival and tongue samples would differ between early periodontitis and health. a cross-sectional evaluation of 141 healthy and early periodontitis adults was performed with the use of oligonucleotide probes and pcr. most species differed in associations with sample sites; most subgingival spec ...	2006	16567551
relationship of serum advanced glycation end products with deterioration of periodontitis in type 2 diabetes patients.	a close relationship between diabetes and chronic periodontitis has been demonstrated. we previously found that porphyromonas gingivalis with the type ii fima gene is an infectious factor closely associated with the deterioration seen in diabetic periodontitis patients. in the present study, we examined whether other biomarkers are related to the development and deterioration of periodontitis often seen in type 2 diabetic individuals.	2006	16579698
local oxygen therapy for treating acute necrotizing periodontal disease in smokers.	the main aim of treatment for acute necrotizing periodontal disease is fast and effective reduction of anaerobic destructive microorganisms to avoid periodontal damage. the effect of adjunctive local oxygen therapy in the treatment of necrotizing periodontal disease was examined in this study.	2006	16579700
langerhans' cell histiocytosis in a 5-year-old girl: evidence of periodontal pathogens.	langerhans' cell histiocytosis (lch) is a rare disorder characterized by langerhans' cell proliferation in various organs or tissues. when periodontal tissue is involved, clinical manifestations can vary from gingival recession and pocket formation to severe alveolar bone loss. this case report describes periodontal pathogens found in the pockets of involved primary teeth.	2006	16584357
identification of oral bacteria associated with crevicular epithelial cells from chronic periodontitis lesions.	bacterial invasion of host epithelial cells plays an important role in the pathogenesis of periodontal diseases; however, the interactions between subgingival species and the gingival crevice cells are not fully understood. this study determined the prevalence of a group of oral bacterial species on or in epithelial cells derived from periodontal pockets and the gingival crevice of subjects with periodontitis. samples of epithelial cells were obtained from 120 sites with periodontal pockets > or ...	2006	16585650
the hemoglobin receptor protein of porphyromonas gingivalis inhibits receptor activator nf-kappab ligand-induced osteoclastogenesis from bone marrow macrophages.	extracellular proteinaceous factors of porphyromonas gingivalis, a periodontal pathogen, that influence receptor activator of nuclear factor-kappab (nf-kappab) ligand (rankl)-induced osteoclastogenesis from bone marrow macrophages were investigated. the culture supernatant of p. gingivalis had the ability to inhibit rankl-induced in vitro osteoclastogenesis. a major protein of the culture supernatant, hemoglobin receptor protein (hbr), suppressed rankl-induced osteoclastogenesis in a dose-depend ...	2006	16622189
inhibitory effects of macrocarpals on the biological activity of porphyromonas gingivalis and other periodontopathic bacteria.	macrocarpals, which are phloroglucinol derivatives contained in eucalyptus leaves, exhibit antimicrobial activity against a variety of bacteria including oral bacteria. this study examined effects of macrocarpals a, b, and c on periodontopathic bacteria, especially porphyromonas gingivalis.	2006	16626372
[quantitative analysis of periodontal pathogens in aggressive periodontitis patients in a japanese population].	the aim of the present study was to clarify the relationship between the relative/absolute numbers of periodontal bacteria and different types of periodontitis. fifteen patients with localized aggressive periodontitis (lagp), 25 patients with generalized aggressive periodontitis (gagp) and 28 patients with chronic periodontitis (cp) were included in this study. saliva and subgingival plaque samples were collected from all subjects for microbiological analysis. the prevalence and proportions of a ...	2006	16629473
escherichia coli acid resistance: ph-sensing, activation by chloride and autoinhibition in gadb.	escherichia coli and other enterobacteria exploit the h+ -consuming reaction catalysed by glutamate decarboxylase to survive the stomach acidity before reaching the intestine. here we show that chloride, extremely abundant in gastric secretions, is an allosteric activator producing a 10-fold increase in the decarboxylase activity at ph 5.6. cooperativity and sensitivity to chloride were lost when the n-terminal 14 residues, involved in the formation of two triple-helix bundles, were deleted by m ...	2006	16675957
prevalence of periodontopathic bacteria on the tongue dorsum of elderly people.	the aim of this study was to analyse the prevalence of oral bacteria on the dorsum of the tongue. in addition, the relationship between the number of teeth and the microflora present on the coating of the tongue in a population of 85-year-old people was assessed.	2006	16677187
whole-genome transcription profiling reveals genes up-regulated by growth on fucose in the human gut bacterium "roseburia inulinivorans".	"roseburia inulinivorans" is an anaerobic polysaccharide-utilizing firmicute bacterium from the human colon that was identified as a producer of butyric acid during growth on glucose, starch, or inulin. r. inulinivorans a2-194 is also able to grow on the host-derived sugar fucose, following a lag period, producing propionate and propanol as additional fermentation products. a shotgun genomic microarray was constructed and used to investigate the switch in gene expression that is involved in chan ...	2006	16740940