Publications

TitleAbstractYear(sorted descending)
Filter
PMID
Filter
genome-wide association study of periodontal pathogen colonization.pathological shifts of the human microbiome are characteristic of many diseases, including chronic periodontitis. to date, there is limited evidence on host genetic risk loci associated with periodontal pathogen colonization. we conducted a genome-wide association (gwa) study among 1,020 white participants of the atherosclerosis risk in communities study, whose periodontal diagnosis ranged from healthy to severe chronic periodontitis, and for whom "checkerboard" dna-dna hybridization quantificat ...201222699663
treponema denticola superoxide reductase: in vivo role, in vitro reactivities, and a novel [fe(cys)(4)] site.in vitro and in vivo results are presented demonstrating that superoxide reductase (sor) from the air-sensitive oral spirochete, treponema denticola (td), is a principal enzymatic scavenger of superoxide in this organism. this sor contains the characteristic non-heme [fe(his)(4)cys] active sites. no other metal-binding domain has been annotated for td sor. however, we found that td sor also accommodates a [fe(cys)(4)] site whose spectroscopic and redox properties resemble those in so-called 2fe- ...201222715932
polymorphic toxin systems: comprehensive characterization of trafficking modes, processing, mechanisms of action, immunity and ecology using comparative genomics.proteinaceous toxins are observed across all levels of inter-organismal and intra-genomic conflicts. these include recently discovered prokaryotic polymorphic toxin systems implicated in intra-specific conflicts. they are characterized by a remarkable diversity of c-terminal toxin domains generated by recombination with standalone toxin-coding cassettes. prior analysis revealed a striking diversity of nuclease and deaminase domains among the toxin modules. we systematically investigated polymorp ...201222731697
the effects of extracellular matrix proteins on neutrophil-endothelial interaction--a roadway to multiple therapeutic opportunities.polymorphoneuclear leukocytes or neutrophils, a major component of white blood cells, contribute to the innate immune response in humans. upon sensing changes in the microenvironment, neutrophils adhere to the vascular wall, migrate through the endothelial cell (ec)-pericyte bilayer, and subsequently through the extracellular matrix to reach the site of inflammation. these cells are capable of destroying microbes, cell debris, and foreign proteins by oxidative and non-oxidative processes. while ...201222737047
halitosis: the multidisciplinary approach.halitosis, bad breath or oral malodour are all synonyms for the same pathology. halitosis has a large social and economic impact. for the majority of patients suffering from bad breath, it causes embarrassment and affects their social communication and life. moreover,halitosis can be indicative of underlying diseases. only a limited number of scientific publications were presented in this field until 1995. ever since, a large amount of research is published, often with lack of evidence. in gener ...201222722640
multiplicity of salmonella entry mechanisms, a new paradigm for salmonella pathogenesis.the salmonella enterica species includes about 2600 diverse serotypes, most of which cause a wide range of food- and water-borne diseases ranging from self-limiting gastroenteritis to typhoid fever in both humans and animals. moreover, some serotypes are restricted to a few animal species, whereas other serotypes are able to infect plants as well as cold- and warm-blooded animals. an essential feature of the pathogenicity of salmonella is its capacity to cross a number of barriers requiring inva ...201223170225
identification of a unique tlr2-interacting peptide motif in a microbial leucine-rich repeat protein.pathogenesis of many bacterially-induced inflammatory diseases is driven by toll-like receptor (tlr) mediated immune responses following recognition of bacterial factors by different tlrs. periodontitis is a chronic inflammation of the tooth supporting apparatus often leading to tooth loss, and is caused by a gram-negative bacterial consortium that includes tannerella forsythia. this bacterium expresses a virulence factor, the bspa, which drives periodontal inflammation by activating tlr2. the n ...201222695115
recent progress in synthetic biology for microbial production of c3-c10 alcohols.the growing need to address current energy and environmental problems has sparked an interest in developing improved biological methods to produce liquid fuels from renewable sources. while microbial ethanol production is well established, higher-chain alcohols possess chemical properties that are more similar to gasoline. unfortunately, these alcohols (except 1-butanol) are not produced efficiently in natural microorganisms, and thus economical production in industrial volumes remains a challen ...201222701113
occurrence of periodontal pathogens among patients with chronic periodontitis.the aim of the present study was to evaluate the presence of the periodontal pathogens that form the red complex (tannerella forsythia, porphyromonas gingivalis and treponema denticola) and aggregatibacter actinomycetemcomitans in patients with chronic periodontitis. the sample consisted of 29 patients with a clinical and radiographic diagnosis of chronic periodontitis based on the criteria of the american academy of periodontology (3). samples for microbiological analysis were collected from th ...201224031906
insights into the virulence of oral biofilms: discoveries from proteomics.this review covers developments in the study of polymicrobial communities, biofilms and selected areas of host response relevant to dental plaque and related areas of oral biology. the emphasis is on recent studies in which proteomic methods, particularly those using mass spectrometry as a readout, have played a major role in the investigation. the last 5-10 years have seen a transition of such methods from the periphery of oral biology to the mainstream, as in other areas of biomedical science. ...201222809209
co-localized or randomly distributed? pair cross correlation of in vivo grown subgingival biofilm bacteria quantified by digital image analysis.the polymicrobial nature of periodontal diseases is reflected by the diversity of phylotypes detected in subgingival plaque and the finding that consortia of suspected pathogens rather than single species are associated with disease development. a number of these microorganisms have been demonstrated in vitro to interact and enhance biofilm integration, survival or even pathogenic features. to examine the in vivo relevance of these proposed interactions, we extended the spatial arrangement analy ...201222655057
causes of adverse pregnancy outcomes and the role of maternal periodontal status - a review of the literature.preterm (pt) and low birth weight (lbw) are considered to be the most relevant biological determinants of newborn infants survival, both in developed and in developing countries. numerous risk factors for pt and lbw have been defined in the literature. infections of the genitourinary tract infections along with various biological and genetic factors are considered to be the most common etiological factors for pt/lbw deliveries. however, evidence suggests that sub-clinical infection sites that ar ...201222615718
relationship between oral anaerobic bacteria and otitis media with effusion.in this study hypothesing the translocation of oral bacteria from oropharynx into the middle ear cavity may be involved in the pathogenesis of otitis media with effusion (ome), we aimed to investigate the presence and similarity of fusobacterium nucleatum and treponema denticola in saliva, nasopharyngeal secretion and the middle ear effusion samples from the children with ome.201222606045
spontaneous periodontitis development in diabetic rats involves an unrestricted expression of inflammatory cytokines and tissue destructive factors in the absence of major changes in commensal oral microbiota.diabetes mellitus is a heterogeneous group of disorders, in which hyperglycemia is a main feature. the objective was to evaluate the involvement of rage, inflammatory cytokines, and metalloproteinases in spontaneous periodontitis triggered by diabetes induction. immunohistochemical procedures for mmp-2, mmp-9, tnf-α, il-1β, il-6, rankl, and rage were performed in rats after 1, 3, 6, 9, and 12 months of diabetes induction. total dna was extracted from paraffin-embedded tissues and evaluated by re ...201222611374
identification of an intracellular m17 family leucine aminopeptidase that is required for virulence in staphylococcus aureus.staphylococcus aureus is a highly virulent bacterial pathogen capable of causing a variety of ailments throughout the human body. it is a major public health concern due to the continued emergence of highly pathogenic methicillin resistant strains (mrsa) both within hospitals and in the community. virulence in s. aureus is mediated by an array of secreted and cell wall associated virulence factors, including toxins, hemolysins and proteases. in this work we identify a leucine aminopeptidase (lap ...201222613209
serum antibodies to periodontal pathogens are a risk factor for alzheimer's disease.chronic inflammation in periodontal disease has been suggested as a potential risk factor in alzheimer's disease (ad). the purpose of this study was to examine serum antibody levels to bacteria of periodontal disease in participants who eventually converted to ad compared with the antibody levels in control subjects.201222546352
prevalence of fima genotypes of porphyromonas gingivalis and other periodontal bacteria in a spanish population with chronic periodontitis.the aim of this study was to determine the prevalence of the different fima genotypes of porphyromonas gingivalis in adult spanish patients with chronic periodontitis, patients with gingivitis and periodontally healthy subjects, and the relationship between these genotypes and other periodontopathogenic bacteria.201222549664
tprc/d (tp0117/131), a trimeric, pore-forming rare outer membrane protein of treponema pallidum, has a bipartite domain structure.identification of treponema pallidum rare outer membrane proteins (omps) has been a longstanding objective of syphilis researchers. we recently developed a consensus computational framework that employs a battery of cellular localization and topological prediction tools to generate ranked clusters of candidate rare omps (d. l. cox et al., infect. immun. 78:5178-5194, 2010). tp0117/tp0131 (tprc/d), a member of the t. pallidum repeat (tpr) family, was a highly ranked candidate. circular dichroism, ...201222389487
oral bacteria and yeasts in relationship to oral ulcerations in hematopoietic stem cell transplant recipients.oral mucositis is a serious and debilitating side effect of conditioning regimens for hematopoietic stem cell transplant (hsct). through hsct, the homeostasis in the oral cavity is disrupted. the contribution of the oral microflora to mucositis remains to be clarified. the aim of our study was to investigate the relationship between yeasts, bacteria associated with periodontitis, and oral ulcerations in hsct recipients.201222531876
regulation of mnth by a dual mn(ii)- and fe(ii)-dependent transcriptional repressor (dr2539) in deinococcus radiodurans.the high intracellular mn/fe ratio observed within the bacteria deinococcus radiodurans may contribute to its remarkable resistance to environmental stresses. we isolated dr2539, a novel regulator of intracellular mn/fe homeostasis in d. radiodurans. electrophoretic gel mobility shift assays (emsas) revealed that dr2539 binds specifically to the promoter of the manganese acquisition transporter (mnth) gene, and that dr0865, the only fur homologue in d. radiodurans, cannot bind to the promoter of ...201222523570
acquisition of complement inhibitor serine protease factor i and its cofactors c4b-binding protein and factor h by prevotella intermedia.infection with the gram-negative pathogen prevotella intermedia gives rise to periodontitis and a growing number of studies implies an association of p. intermedia with rheumatoid arthritis. the serine protease factor i (fi) is the central inhibitor of complement degrading complement components c3b and c4b in the presence of cofactors such as c4b-binding protein (c4bp) and factor h (fh). yet, the significance of complement inhibitor acquisition in p. intermedia infection and fi binding by gram-n ...201222514678
papillon-lefèvre syndrome: case report and review of the literature.papillon-lefèvre syndrome is a very rare syndrome of autosomal recessive inheritance characterized by palmar-plantar hyperkeratosis and early onset of a severe destructive periodontitis leading to premature loss of both primary and permanent dentitions. various etiopathogenic factors are associated with the syndrome; but a recent report has suggested that the condition is linked to mutations of the cathepsin c gene. two cases of papillon-lefèvre syndrome in the same family, having all of the cha ...201223055596
association between interleukin-1 gene polymorphism and severity of chronic periodontitis in a south indian population group.periodontitis is a bacterial disease modified by multiple factors. interleukin-1 (il-1) is a key regulator of the host response and a major modulator of extracellular matrix catabolism and bone resorption. it has been reported that variations in il-1 gene are associated with increased susceptibility to periodontitis. the aims of the study were 1) to analyze the distribution of single nucleotide polymorphism of il-1 (il-1a-+4845 and il-1b-+3954) and 2) to correlate the association of the composit ...201223055581
effect of periodontal pathogens on the metatranscriptome of a healthy multispecies biofilm model.oral bacterial biofilms are highly complex microbial communities with up to 700 different bacterial taxa. we report here the use of metatranscriptomic analysis to study patterns of community gene expression in a multispecies biofilm model composed of species found in healthy oral biofilms (actinomyces naeslundii, lactobacillus casei, streptococcus mitis, veillonella parvula, and fusobacterium nucleatum) and the same biofilm plus the periodontopathogens porphyromonas gingivalis and aggregatibacte ...201222328675
features of two proteins of leptospira interrogans with potential role in host-pathogen interactions.leptospirosis is considered a re-emerging infectious disease caused by pathogenic spirochaetes of the genus leptospira. pathogenic leptospires have the ability to survive and disseminate to multiple organs after penetrating the host. leptospires were shown to express surface proteins that interact with the extracellular matrix (ecm) and to plasminogen (plg). this study examined the interaction of two putative leptospiral proteins with laminin, collagen type i, collagen type iv, cellular fibronec ...201222463075
treponema denticola chymotrypsin-like proteinase (ctlp) integrates spirochaetes within oral microbial communities.treponema denticola is found ubiquitously in the human oral cavity and is mainly associated with bacterial communities implicated in the establishment and development of periodontal disease. the ability to become integrated within biofilm communities is crucial to the growth and survival of oral bacteria, and involves inter-bacterial coaggregation, metabolic cooperation, and synergy against host defences. in this article we show that the chymotrypsin-like proteinase (ctlp), found within a high-m ...201222313692
chemically modified tetracyclines: novel therapeutic agents in the management of chronic periodontitis.chronic periodontitis is a complex infection initiated by gram-negative bacteria which destroy the supporting structures of the tooth. recently, it has been recognized that it is the host response to bacterial infection which causes greater destruction of the connective tissue elements, periodontal ligament and alveolar bone in periodontitis. this has led to the development of various host modulating approaches to target cells and their destructive mediators involved in tissue degradation. chemi ...201222529468
understanding the roles of gingival beta-defensins.gingival epithelium produces β-defensins, small cationic peptides, as part of its contribution to the innate host defense against the bacterial challenge that is constantly present in the oral cavity. besides their functions in healthy gingival tissues, β-defensins are involved in the initiation and progression, as well as restriction of periodontal tissue destruction, by acting as antimicrobial, chemotactic, and anti-inflammatory agents. in this article, we review the common knowledge about β-d ...201222389759
host-pathogen dynamics: it's complicated! 201222368768
treponema denticola interactions with host proteins.oral treponema species, most notably t. denticola, are implicated in the destructive effects of human periodontal disease. progress in the molecular analysis of interactions between t. denticola and host proteins is reviewed here, with particular emphasis on the characterization of surface-expressed and secreted proteins of t. denticola involved in interactions with host cells, extracellular matrix components, and components of the innate immune system.201222368767
involvement of a periodontal pathogen, porphyromonas gingivalis on the pathogenesis of non-alcoholic fatty liver disease.non-alcoholic fatty liver disease (nafld) is a hepatic manifestation of metabolic syndrome that is closely associated with multiple factors such as obesity, hyperlipidemia and type 2 diabetes mellitus. however, other risk factors for the development of nafld are unclear. with the association between periodontal disease and the development of systemic diseases receiving increasing attention recently, we conducted this study to investigate the relationship between nafld and infection with porphyro ...201222340817
microbiologic profile of endodontic infections from hiv- and hiv+ patients using multiple-displacement amplification and checkerboard dna-dna hybridization.to compare the microbiota of endodontic infections in necrotic pulp from hiv-negative and hiv-positive subjects.201222335194
beta-hexosaminidase activity of the oral pathogen tannerella forsythia influences biofilm formation on glycoprotein substrates.tannerella forsythia is an important pathogen in periodontal disease. previously, we showed that its sialidase activity is key to utilization of sialic acid from a range of human glycoproteins for biofilm growth and initial adhesion. removal of terminal sialic acid residues often exposes β-linked glucosamine or galactosamine, which may also be important adhesive molecules. in turn, these residues are often removed by a group of enzymes known as β-hexosaminidases. we show here that t. forsythia h ...201222276920
rheumatoid arthritis and periodontitis - inflammatory and infectious connections. review of the literature.an association between oral disease/periodontitis and rheumatoid arthritis (ra) has been considered since the early 1820s. the early treatment was tooth eradication. epidemiological studies suggest that the prevalence of ra and periodontitis may be similar and about 5% of the population are aged 50 years or older. ra is considered as an autoimmune disease whereas periodontitis has an infectious etiology with a complex inflammatory response. both diseases are chronic and may present with bursts o ...201222347541
analysis of the salivary microbiome using culture-independent techniques.the salivary microbiota is a potential diagnostic indicator of several diseases. culture-independent techniques are required to study the salivary microbial community since many of its members have not been cultivated.201222300522
disabled patients and oral health in rome, italy: long-term evaluation of educational initiatives.this study is concerned with the educational intervention layout proposed as a possible answer for the disparities in healthcare services for disabled persons.201222545186
disabled patients and oral health in rome, italy: long-term evaluation of educational initiatives.this study is concerned with the educational intervention layout proposed as a possible answer for the disparities in healthcare services for disabled persons.201222545186
a metalloproteinase karilysin present in the majority of tannerella forsythia isolates inhibits all pathways of the complement system.tannerella forsythia is a poorly studied pathogen despite being one of the main causes of periodontitis, which is an inflammatory disease of the supporting structures of the teeth. we found that despite being recognized by all complement pathways, t. forsythia is resistant to killing by human complement, which is present at up to 70% of serum concentration in gingival crevicular fluid. incubation of human serum with karilysin, a metalloproteinase of t. forsythia, resulted in a decrease in bacter ...201222287711
analysis of the cell surface layer ultrastructure of the oral pathogen tannerella forsythia.the gram-negative oral pathogen tannerella forsythia is decorated with a 2d crystalline surface (s-) layer, with two different s-layer glycoprotein species being present. prompted by the predicted virulence potential of the s-layer, this study focused on the analysis of the arrangement of the individual s-layer glycoproteins by a combination of microscopic, genetic, and biochemical analyses. the two s-layer genes are transcribed into mrna and expressed into protein in equal amounts. the s-layer ...201222273979
non-inflammatory destructive periodontal disease: a clinical, microbiological, immunological and genetic investigation.periodontitis comprises a group of multifactorial diseases in which periodontopathogens accumulate in dental plaque and trigger host chronic inflammatory and immune responses against periodontal structures, which are determinant to the disease outcome. although unusual cases of non-inflammatory destructive periodontal disease (nidpd) are described, their pathogenesis remains unknown. a unique nidpd case was investigated by clinical, microbiological, immunological and genetic tools. the patient, ...201222437688
intraperiodontal pocket: an ideal route for local antimicrobial drug delivery.periodontal pockets act as a natural reservoir filled with gingival crevicular fluid for the controlled release delivery of antimicrobials directly. this article reflects the present status of nonsurgical controlled local intrapocket delivery of antimicrobials in the treatment of periodontitis. these sites have specialty in terms of anatomy, permeability, and their ability to retain a delivery system for a desired length of time. a number of antimicrobial products and the composition of the deli ...201222470888
bacterial invasion of vascular cell types: vascular infectology and atherogenesis.to portray the chronic inflammation in atherosclerosis, leukocytic cell types involved in the immune response to invading pathogens are often the focus. however, atherogenesis is a complex pathological deterioration of the arterial walls, where vascular cell types are participants with regards to deterioration and disease. since other recent reviews have detailed the role of both the innate and adaptive immune response in atherosclerosis, herein we will summarize the latest developments regardin ...201222185451
Identification of iron-regulated genes of Bifidobacterium breve UCC2003 as a basis for controlled gene expression.Iron is an essential growth factor for virtually all organisms. However, iron is not readily available in most environments and microorganisms have evolved specialized mechanisms, such as the use of siderophores and high-affinity transport systems, to acquire iron when confronted with iron-limiting conditions. In general these systems are tightly regulated to prevent iron-induced toxicity and because they are quite costly to the microbe. Because of this tight regulation we chose to explore the r ...201222179149
Co-expression of Arabidopsis thaliana phytochelatin synthase and Treponema denticola cysteine desulfhydrase for enhanced arsenic accumulation.Arsenic is one of the most hazardous pollutants found in aqueous environments and has been shown to be a carcinogen. Phytochelatins (PCs), which are cysteine-rich and thio-reactive peptides, have high binding affinities for various metals including arsenic. Previously, we demonstrated that genetically engineered Saccharomyces cerevisiae strains expressing phytochelatin synthase (AtPCS) produced PCs and accumulated arsenic. In an effort to further improve the overall accumulation of arsenic, cyst ...201221915851
pathogenic microbes and community service through manipulation of innate immunity.the periodontal pathogen porphyromonas gingivalis undermines major components of innate immunity, such as complement, toll-like receptors (tlr), and their crosstalk pathways. at least in principle, these subversive activities could promote the adaptive fitness of the entire periodontal biofilm community. in this regard, the virulence factors responsible for complement and tlr exploitation (gingipain enzymes, atypical lipopolysaccharide molecules, and fimbriae) are released as components of readi ...201221948363
animal models to study host-bacteria interactions involved in periodontitis.animal models have distinct advantages because they can mimic cellular complexities that occur in humans in vivo and are often more accurate than in vitro studies that take place on plastic surfaces with limited numbers of cell types present. furthermore, cause and effect relationships can be established by applying inhibitors or activators or through the use of genetically modified animals. such gain or loss of function studies are often difficult to achieve in human clinical studies, particula ...201222142960
variations of oral microbiota are associated with pancreatic diseases including pancreatic cancer.objectivethe associations between oral diseases and increased risk of pancreatic cancer have been reported in several prospective cohort studies. in this study, we measured variations of salivary microbiota and evaluated their potential associations with pancreatic cancer and chronic pancreatitis.methodsthis study was divided into three phases: (1) microbial profiling using the human oral microbe identification microarray to investigate salivary microbiota variation between 10 resectable patient ...201121994333
variations of oral microbiota are associated with pancreatic diseases including pancreatic cancer.objectivethe associations between oral diseases and increased risk of pancreatic cancer have been reported in several prospective cohort studies. in this study, we measured variations of salivary microbiota and evaluated their potential associations with pancreatic cancer and chronic pancreatitis.methodsthis study was divided into three phases: (1) microbial profiling using the human oral microbe identification microarray to investigate salivary microbiota variation between 10 resectable patient ...201121994333
Treatment of residual pockets with photodynamic therapy, diode laser, or deep scaling. A randomized, split-mouth controlled clinical trial.The objective of this work was to compare the effects of antimicrobial photodynamic therapy (PDT), diode soft laser therapy (DSL), and thorough deep scaling and root planing (SRP) for treatment of residual pockets. Thirty-two subjects with a history of non-surgical treatment for chronic periodontitis were included. Residual pockets >4 mm and bleeding upon probing were debrided with an ultrasonic device and then subjected to either PDT, DSL, or SRP. Pocket probing depth (PPD), bleeding on probing ...201122105837
human microbiome and hiv/aids.understanding of the human microbiome continues to grow rapidly; however, reports on changes in the microbiome after hiv infection are still limited. this review surveys the progress made in methodology associated with microbiome studies and highlights the remaining challenges to this field. studies have shown that commensal oral, gut, vaginal, and penile bacteria are vital to the health of the human immune system. our studies on crosstalk among oral and gastrointestinal soluble innate factors, ...201122193889
A New Real-Time PCR Assay for Improved Detection of the Parasite Babesia microti.Babesiosis is an emerging zoonosis with important public health implications, as the incidence of the disease has risen dramatically over the past decade. Because the current gold standard for detection of Babesia is microscopic examination of blood smears, accurate identification requires trained personnel. Species in the genus cannot be distinguished microscopically, and Babesia can also be confused with the early trophozoite stage (ring forms) of Plasmodium parasites. To allow more accurate d ...201122170915
colonisation of the oral cavity by periodontopathic bacteria in complete denture wearers.gerodontology 2011; doi: 10.1111/j.1741-2358.2011.00506.x colonisation of the oral cavity by periodontopathic bacteria in complete denture wearers objective:  the purpose of this study was to investigate colonisation by periodontopathic bacteria and the sites of colonisation in elderly upper and lower complete denture wearers. we also investigated the relationship between level of oral hygiene and colonisation by periodontopathic bacteria. materials and methods:  forty edentulous and 37 dentate ...201121929616
life cycle stage-resolved proteomic analysis of the excretome/secretome from strongyloides ratti--identification of stage-specific proteases.a wide range of biomolecules, including proteins, are excreted and secreted from helminths and contribute to the parasite's successful establishment, survival, and reproduction in an adverse habitat. excretory and secretory proteins (esp) are active at the interface between parasite and host and comprise potential targets for intervention. the intestinal nematode strongyloides spp. exhibits an exceptional developmental plasticity in its life cycle characterized by parasitic and free-living gener ...201121964353
Comparative analysis of salivary bacterial microbiome diversity in edentulous infants and their mothers or primary care givers using pyrosequencing.Bacterial contribution to oral disease has been studied in young children, but there is a lack of data addressing the developmental perspective in edentulous infants. Our primary objectives were to use pyrosequencing to phylogenetically characterize the salivary bacterial microbiome of edentulous infants and to make comparisons against their mothers. Saliva samples were collected from 5 edentulous infants (mean age?=?4.6±1.2 mo old) and their mothers or primary care givers (mean age?=?30.8±9.5 y ...201121853142
the capsule of porphyromonas gingivalis leads to a reduction in the host inflammatory response, evasion of phagocytosis, and increase in virulence.periodontal disease is a chronic oral inflammatory disease that is triggered by bacteria such as porphyromonas gingivalis. p. gingivalis strains exhibit great heterogeneity, with some strains being encapsulated while others are nonencapsulated. although the encapsulated strains have been shown to be more virulent in a mouse abscess model, so far the role of the capsule in p. gingivalis interactions with host cells is not well understood and its role in virulence has not been defined. here, we in ...201121911459
molecular detection of human periodontal pathogens in oral swab specimens from dogs in japan.periodontal diseases are known to be major diseases in humans, and are also common in dogs. the purpose of the present study was to analyze the distribution of periodontitis-related bacterial species using oral swab specimens collected from 26 pet dogs. the distribution of an animal gingival organism porphyromonas gulae, in addition to 10 human periodontitis-related bacterial species, including porphyromonas gingivalis, treponema denticola, tannerella forsythia, capnocytophaga ochracea, capnocyt ...201121916371
[Role of several periodontopathogenic microorganisms and tlr4 gene Asp299Gly polymorphism in atherosclerosis pathogenesis].Establishment of presence of periodonto-pathogenic microorganisms in atherosclerosis plaque and surrounding tissues, and possible relation of development of atherosclerosis and TLR4 gene Asp299Gly polymorphism in ischemic heart disease patients (IHD).201122145357
evidence for graft colonization with periodontal pathogens in lung transplant recipients.summary bronchiolitis obliterans syndrome (bos) is a major cause of late graft dysfunction in lung transplant recipients. there is increasing evidence that beside alloimmunologic injury also non-alloimmunologic inflammatory conditions may raise the risk of acute and chronic rejection. the oral cavity represents a possible reservoir for pathogenic bacteria due to its close anatomical proximity. in this pilot study, the presence of pathogenic periodontal bacteria in the oral cavity as well as in t ...201122203528
correlation network analysis applied to complex biofilm communities.the complexity of the human microbiome makes it difficult to reveal organizational principles of the community and even more challenging to generate testable hypotheses. it has been suggested that in the gut microbiome species such as bacteroides thetaiotaomicron are keystone in maintaining the stability and functional adaptability of the microbial community. in this study, we investigate the interspecies associations in a complex microbial biofilm applying systems biology principles. using corr ...201122163302
the relationship of the oral microbiotia to periodontal health and disease.the oral microbial community represents the best-characterized consortium associated with the human host. there are strong correlations between the qualitative composition of the oral microbiota and clinically healthy or diseased states. however, additional studies are needed to elucidate the mechanisms that define these microbial/host relationships.201122018230
detection of periodontal pathogens in newborns and children with mixed dentition.we report the age-related prevalence of red complex periodontal pathogens, porphyromonas gingivalis, treponema denticola, and tannerella forsythia, along with four strains of orange complex pathogens. the bacteria present in samples isolated from tongue, cheek, and subgingival sulcus in edentulous newborns and children with mixed dentition were monitored by polymerase chain reaction (pcr). p. gingivalis was not detected in any site of any subject in the two groups tested. however, t. denticola w ...201121928086
a machine-learning approach to identify hydrogenosomal proteins in trichomonas vaginalis.the protozoan parasite trichomonas vaginalis is the causative agent of trichomoniasis, the most widespread non-viral sexually transmitted disease in humans. it possesses hydrogenosomes - anaerobic mitochondria that generate h(2), co(2), and acetate from pyruvate while converting adp to atp via substrate level phosphorylation. t. vaginalis hydrogenosomes lack a genome and translation machinery, hence they import all their proteins from the cytosol, but to date only 30 imported proteins have been ...201122140228
the antibacterial activity of ll-37 against treponema denticola is dentilisin-protease independent and facilitated by the major outer sheath protein virulence factor.host defense peptides are innate immunoeffectors that possess both bactericidal activities and immunomodulatory functions. deficiency in the human ll-37 host defense peptide has been previously correlated with severe periodontal disease. treponema denticola is an oral anaerobic spirochete closely associated with the pathogenesis of periodontal disease. the t. denticola major surface protein (msp), involved in adhesion and in cytotoxicity, and the dentilisin serine protease are key virulence fact ...201122184422
relationship between periodontal diseases and preterm birth: recent epidemiological and biological data.for ten years, the incidence of preterm birth does not decrease in developed countries despite the promotion of public health programs. many risk factors have been identified including ethnicity, age, tobacco, and infection. however, almost 50% of preterm birth causes remain unknown. the periodontal diseases are highly prevalent inflammatory and infectious diseases of tooth supporting tissues leading to an oral disability. they influence negatively general health worsening cardiovascular disease ...201122132334
salivary levels of antibacterial peptide (ll-37/hcap-18) and cotinine in periodontitis patients.background: the purpose of this study was to examine the relationship between salivary ll-37 levels and clinical severity in chronic periodontitis (cp) patients. the presence/absence of four periodontopathic bacteria and salivary cotinine levels were also examined in order to assess the impact of these factors on ll-37 production. methods: unstimulated salivary samples were collected from 69 cp patients. salivary concentrations of ll-37 and cotinine were measured by enzyme-linked immunosorbent ...201121942788
characterization and scope of s-layer protein o-glycosylation in tannerella forsythia.cell surface glycosylation is an important element in defining the life of pathogenic bacteria. tannerella forsythia is a gram-negative, anaerobic periodontal pathogen inhabiting the subgingival plaque biofilms. it is completely covered by a two-dimensional crystalline surface layer (s-layer) composed of two glycoproteins. although the s-layer has previously been shown to delay the bacterium's recognition by the innate immune system, we characterize here the s-layer protein o-glycosylation as a ...201121911490
Porphyromonas gingivalis: a clonal pathogen?: Diversities in housekeeping genes and the major fimbriae gene.The introduction of multilocus sequence typing (MLST) in infectious disease research has allowed standardized typing of bacterial clones. Through multiple markers around the genome, it is possible to determine the sequence type (ST) of bacterial isolates to establish the population structure of a species. For the periodontal pathogen, Porphyromonas gingivalis, the MLST scheme has been established at www.pubmlst.org/pgingivalis, and data from the database indicate a high degree of genetic diversi ...201122125739
Protease inhibitor levels in periodontal health and disease.Kretschmar S, Yin L, Roberts F, London R, Flemmig TT, Arushanov D, Kaiyala K, Chung WO. Protease inhibitor levels in periodontal health and disease. J Periodont Res 2011; doi: 10.1111/j.1600-0765.2011.01425.x. © 2011 John Wiley & Sons A/S Background and Objective: Our previous study showed that protease inhibitors were attenuated by the periodontal pathogen Porphyromonas gingivalis in cultured gingival epithelial cells. We hypothesize that fewer protease inhibitors would be present in more adva ...201122029638
Protease inhibitor levels in periodontal health and disease.Kretschmar S, Yin L, Roberts F, London R, Flemmig TT, Arushanov D, Kaiyala K, Chung WO. Protease inhibitor levels in periodontal health and disease. J Periodont Res 2011; doi: 10.1111/j.1600-0765.2011.01425.x. © 2011 John Wiley & Sons A/S Background and Objective: Our previous study showed that protease inhibitors were attenuated by the periodontal pathogen Porphyromonas gingivalis in cultured gingival epithelial cells. We hypothesize that fewer protease inhibitors would be present in more adva ...201122029638
role of sialidase in glycoprotein utilization by tannerella forsythia.the major bacterial pathogens associated with periodontitis include tannerella forsythia. we previously discovered that sialic acid stimulates biofilm growth of t. forsythia, and that sialidase activity is key to utilization of sialoconjugate sugars and is involved in host-pathogen interactions in vitro. the aim of this work was to assess the influence of the nanh sialidase on initial biofilm adhesion and growth in experiments where the only source of sialic acid was sialoglycoproteins or human ...201121885482
Conservation of the C-type lectin fold for massive sequence variation in a Treponema diversity-generating retroelement.Anticipatory ligand binding through massive protein sequence variation is rare in biological systems, having been observed only in the vertebrate adaptive immune response and in a phage diversity-generating retroelement (DGR). Earlier work has demonstrated that the prototypical DGR variable protein, major tropism determinant (Mtd), meets the demands of anticipatory ligand binding by novel means through the C-type lectin (CLec) fold. However, because of the low sequence identity among DGR variabl ...201121873231
the effect of spiramycin on porphyromonas gingivalis and other "classic" periopathogens.in clinical trials, spiramycin has shown additional benefit overscaling and root planing on pocket depth reduction, but its effect on periodontal microbiota was evaluated only by darkfield microscopy. therefore, this study was conducted to determine the effect of spiramycin administration on porphyromonas gingivalis and other periodontopathic bacteria using 16s rarn pcr technique. thirty two non-smoker adults with untreated periodontitis and pocket depth > or = 7 mm. were evaluated to participat ...201122010417
clinical and microbiological evaluation, by real-time pcr, of non-surgical treatment of aggressive periodontitis associated with amoxicillin and metronidazole.background: to evaluate the clinical and microbiological changes resulting from non-surgical periodontal treatment associated with amoxicillin and metronidazole, in individuals with aggressive periodontitis (agp). methods: 15 subjects with agp received non-surgical periodontal treatment and 45 days after completion of treatment, were treated with antibiotics. clinical data and samples of subgingival plaque were collected at baseline, 45 days after the non-surgical periodontal treatment and 1 mon ...201122060046
symptomatic and asymptomatic apical periodontitis associated with red complex bacteria: clinical and microbiological evaluation.in this study, the association of red complex (rc) bacteria that include treponema denticola, tannerella forsythia and porphyromonas gingivalis with acute, exacerbated or chronic apical periodontitis was evaluated. seventy-one patients with periapical disease were evaluated by clinical examination and microbiological samples obtained from the root canals were analyzed by a polymerase chain reaction assay. twenty-one (29.6%) samples were positive for rc bacteria, with t. ...201122143381
tobacco smoke augments porphyromonas gingivalis-streptococcus gordonii biofilm formation.smoking is responsible for the majority of periodontitis cases in the us and smokers are more susceptible than non-smokers to infection by the periodontal pathogen porphyromonas gingivalis. p. gingivalis colonization of the oral cavity is dependent upon its interaction with other plaque bacteria, including streptococcus gordonii. microarray analysis suggested that exposure of p. gingivalis to cigarette smoke extract (cse) increased the expression of the major fimbrial antigen (fima), but not the ...201122110637
genetic organisation, mobility and predicted functions of genes on integrated, mobile genetic elements in sequenced strains of clostridium difficile.clostridium difficile is the leading cause of hospital-associated diarrhoea in the us and europe. recently the incidence of c. difficile-associated disease has risen dramatically and concomitantly with the emergence of 'hypervirulent' strains associated with more severe disease and increased mortality. c. difficile contains numerous mobile genetic elements, resulting in the potential for a highly plastic genome. in the first sequenced strain, 630, there is one proven conjugative transposon (ctn) ...201121876735
Associations of periodontal microorganisms with salivary proteins and MMP-8 in gingival crevicular fluid.OBJECTIVE: We investigated in subjects with and without periodontitis, the levels of certain salivary proteins and matrix metalloproteinase-8 (MMP-8) in gingival crevicular fluid (GCF), in relation to the presence of specific periodontal pathogens. METHODS: Clinical parameters were recorded at baseline, in 1985 and in 2009 from 99 subjects; 56 with and 43 without periodontitis (mean age 59.2 ± SD 2.9). Saliva samples collected in 2009 were analysed for salivary albumin, total protein and immunog ...201122103335
competitive selection of lactic acid bacteria that persist in the human oral cavity.lactic acid bacteria (lab) might offer opportunities as oral probiotics provided candidate strains persist in the mouth. after intake of a mixture of 69 lab, strains of lactobacillus fermentum and lactobacillus salivarius were especially recovered. coaggregation with other microbes is likely not a prerequisite for persistence since l. salivarius strongly coaggregated with typical oral cavity isolates, whereas l. fermentum failed to display this phenotype.201121965405
microbiologic findings 1 year after partial- and full-mouth scaling in the treatment of moderate chronic periodontitis.to investigate the impact on microbiologic variables of full-mouth scaling (fms) and conventional scaling and root planing (csrp) after 12 months.201121909493
prevalence of sos-mediated control of integron integrase expression as an adaptive trait of chromosomal and mobile integrons.abstract:201121529368
chey3 of borrelia burgdorferi is the key response regulator essential for chemotaxis and forms a long-lived phosphorylated intermediate.spirochetes have a unique cell structure: these bacteria have internal periplasmic flagella subterminally attached at each cell end. how spirochetes coordinate the rotation of the periplasmic flagella for chemotaxis is poorly understood. in other bacteria, modulating flagellar rotation is essential for chemotaxis, and phosphorylation-dephosphorylation of the response regulator chey plays a key role in regulating this rotary motion. the genome of the lyme disease spirochete borrelia burgdorferi c ...201121531807
dendritic cells, antibodies reactive with oxldl, and inflammation.periodontitis appears to promote chronic inflammatory diseases, including atherosclerosis, but relevant mechanisms need clarification. oral bacteria induce antibodies that bind not only bacteria, but also oxldl. porphyromonas gingivalis and aggregatibacter actinomycetemcomitans induce remarkable igg responses that are dominated by igg2, and igg2 is ifn-γ-dependent and is promoted by dendritic cells (dcs). ldl-reactive antibodies induced by p. gingivalis and a. actinomycetemcomitans include anti- ...201121531918
the diguanylate cyclase, rrp1, regulates critical steps in the enzootic cycle of the lyme disease spirochetes.rrp1 is the sole c-di-gmp-producing protein (diguanylate cyclase) of borrelia burgdorferi. to test the hypothesis that rrp1 regulates critical processes involved in the transmission of spirochetes between ticks and mammals, an rrp1 deletion mutant (b31-δrrp1) and a strain that constitutively produces elevated levels of rrp1 (b31-ov) were constructed. the strains were assessed for progression through the enzootic cycle using an ixodes tick/c3h-hej mouse model and tick immersion feeding methods. b ...201121542866
effect of periodontopathogen lipopolysaccharides and proinflammatory cytokines on cd46, cd55, and cd59 gene/protein expression by oral epithelial cells.membrane-anchored complement regulatory proteins (crps), including cd46, cd55, and cd59, protect host cells from complement attack. in the present study, we investigated whether periodontopathogen lipopolysaccharide and proinflammatory cytokines modulate crp gene/protein expression in human oral epithelial cells. the lipopolysaccharide of treponema denticola and tannerella forsythia were the most potent for increasing the gene expression of cd55 and cd59, and to a lesser extent cd46, after a 48- ...201121545652
streptococcus mutans strains recovered from caries-active or caries-free individuals differ in sensitivity to host antimicrobial peptides.antimicrobial peptides (amps) are among the repertoire of host innate immune defenses. in the oral cavity, several amps are present in saliva and have antimicrobial activities against oral bacteria, including streptococcus mutans, a primary etiological agent of dental caries. in this study, we hypothesized that unique s. mutans strains, as determined by dna fingerprinting from sixty 13-year-old subjects with or without experience of caries, would have different susceptibilities to α-defensins-1- ...201121545696
treponema denticola pure is a bacterial air carboxylase.de novo purine biosynthesis proceeds by two divergent paths. in bacteria, yeasts, and plants, 5-aminoimidazole ribonucleotide (air) is converted to 4-carboxy-air (cair) by two enzymes: n(5)-carboxy-air (n(5)-cair) synthetase (purk) and n(5)-cair mutase (class i pure). in animals, the conversion of air to cair requires a single enzyme, air carboxylase (class ii pure). the cair carboxylate derives from bicarbonate or co(2), respectively. class i pure is a promising antimicrobial target. class i an ...201121548610
identification of mono- or poly-specific monoclonal antibody to porphyromonas gingivalis heat-shock protein 60.the aim of this study was to define the immunoreactive specificity of porphyromonas gingivalis (p. gingivalis) heat shock protein (hsp) 60 in periodontitis and atherosclerosis.201121556254
diagnostic evaluation of a nanobody with picomolar affinity toward the protease rgpb from porphyromonas gingivalis.porphyromonas gingivalis is one of the major periodontitis-causing pathogens. p. gingivalis secretes a group of proteases termed gingipains, and in this study we have used the rgpb gingipain as a biomarker for p. gingivalis. we constructed a naive camel nanobody library and used phage display to select one nanobody toward rgpb with picomolar affinity. the nanobody was used in an inhibition assay for detection of rgpb in buffer as well as in saliva. the nanobody was highly specific for rgpb given ...201121569755
metabolic engineering of cyanobacteria for 1-butanol production from carbon dioxide.production and chemicals or fuels directly from co(2) is an attractive approach to solving the energy and environmental problems. 1-butanol, a chemical feedstock and potential fuel, has been produced by fermentation of carbohydrates, both in native clostridium species and various engineered hosts. to produce 1-butanol from co(2), we transferred a modified coa-dependent 1-butanol production pathway into a cyanobacterium, synechococcus elongatus pcc 7942. we demonstrated the activity of each enzym ...201121569861
disruption of a type ii endonuclease (tde0911) enables treponema denticola atcc 35405 strain to accept an unmethylated shuttle vector.the oral spirochete treponema denticola is associated with human periodontal disease. t. denticola atcc 35405 (td(35405)) and 33520 (td(33520)) are two routinely used laboratory strains. compared to td(33520), td(35405) is more virulent but less accessible to genetic manipulations. for instance, the shuttle vectors of td(33520) cannot be transformed into td(35405). the lack of a shuttle vector has been a barrier to study the biology and virulence of td(35405). in this report, we hypothesize that ...201121602384
levels of serum igg specific to the bspa protein of tannerella forsythia are related to the periodontal status.background: tannerella forsythia is a gram-negative anaerobe implicated in the development of periodontal disease (pd). bspa is a surface expressed and secreted protein, recognized as an important virulence factor of t. forsythia. this study was undertaken to determine if t. forsythia bacterial surface protein a (bspa) induces an antibody response in pd. we hypothesized that serum immunoglobulin g (igg) antibody levels against bspa will correlate with patient's disease. methods: sera were obtain ...201121609257
levels of serum igg specific to the bspa protein of tannerella forsythia are related to the periodontal status.background: tannerella forsythia is a gram-negative anaerobe implicated in the development of periodontal disease (pd). bspa is a surface expressed and secreted protein, recognized as an important virulence factor of t. forsythia. this study was undertaken to determine if t. forsythia bacterial surface protein a (bspa) induces an antibody response in pd. we hypothesized that serum immunoglobulin g (igg) antibody levels against bspa will correlate with patient's disease. methods: sera were obtain ...201121609257
identification of periodontal pathogens in healthy periimplant sites.: the aim of this study was to evaluate the presence of periodontopathogens in subgingival periimplant sites in partially edentulous patients using polymerase chain reaction procedures, with regard to areas with clinical and radiographic signs of health and areas presenting periimplant disease.201121613949
riboswitch regulates a thiamine pyrophosphate (tpp) abc transporter of the oral spirochete treponema denticola.thiamine pyrophosphate (tpp), a biologically active form of thiamine (vitamin b1), is an essential cofactor in all living systems. microorganisms either synthesize tpp via de novo biosynthesis pathways or uptake exogenous thiamine from the environment via specific transporters. the oral spirochete treponema denticola is an important pathogen that is associated with human periodontal diseases. it lacks a de novo tpp biosynthesis pathway and needs exogenous tpp for the growth, suggesting that it m ...201121622748
experimental alveolitis in rats: microbiological, acute phase response and histometric characterization of delayed alveolar healing.the pathogenesis of alveolitis is not well known and therefore experimental situations that mimic some features of this disease should be developed.201121625744
tlr2 signaling and th2 responses drive tannerella forsythia-induced periodontal bone loss.periodontal disease (pd) is a chronic inflammation of the tooth-supporting soft tissue and alveolar bone due to infection by a select group of gram-negative microbes, which leads to tooth loss if untreated. because mice deficient in cd4(+) cells are resistant to infection-induced alveolar bone loss, th cells have been implicated in bone-destructive processes during pd. however, the extent to which different th cell subtypes play roles in pathogenesis or host protection remains to be defined and ...201121632710
the pathogenic persona of community-associated oral streptococci.the mitis group streptococci (mgs) are widespread in the oral cavity and are traditionally associated with oral health. however, these organisms have many attributes that contribute to the development of pathogenic oral communities. mgs adhere rapidly to saliva-coated tooth surfaces, thereby providing an attachment substratum for more overtly pathogenic organisms such as porphyromonas gingivalis, and the two species assemble into heterotypic communities. close physical association facilitates ph ...201121635580
crystallization of the factor h-binding protein, fhbb, from the periopathogen treponema denticola.treponema denticola is a primary etiological agent of periodontal disease. t. denticola evades complement-mediated killing by binding to the host's factor h (fh), a negative regulator of the alternative complement pathway. the t. denticola fh-binding protein has been identified and designated as factor h-binding protein b (fhbb). crystals of recombinant fhbb were obtained by the hanging-drop vapor-diffusion method using sodium citrate and 0.2 m sodium thiocyanate. fhbb crystals diffracted to 1.8 ...201121636910
complete genome sequence of treponema paraluiscuniculi, strain cuniculi a: the loss of infectivity to humans is associated with genome decay.treponema paraluiscuniculi is the causative agent of rabbit venereal spirochetosis. it is not infectious to humans, although its genome structure is very closely related to other pathogenic treponema species including treponema pallidum subspecies pallidum, the etiological agent of syphilis. in this study, the genome sequence of treponema paraluiscuniculi, strain cuniculi a, was determined by a combination of several high-throughput sequencing strategies. whereas the overall size (1,133,390 bp), ...201121655244
diversity and plasticity of the intracellular plant pathogen and insect symbiont, 'candidatus liberibacter asiaticus', revealed by hyper variable prophage genes with intragenic tandem repeats.'candidatus liberibacter asiaticus' (las) is a psyllid-transmitted, phloem-limited alpha proteobacterium, and the most prevalent species of liberibacter associated with a devastating worldwide citrus disease known as huanglongbing (hlb). two related and hyper variable genes (hyvi and hyvii) were identified in the prophage regions of the psy62 las genome. sequence analyses of the hyvi/hyvii genes in 35 las dna isolates collected globally revealed hyvi gene contains up to12 nearly identical tandem ...201121784907
Refresh
firstprev
...11121314151617181920...
nextlast
Displaying items 1101 - 1200 of 2695