Draft Genome Sequences of Three Clinical Isolates of Tannerella forsythia Isolated from Subgingival Plaque from Periodontitis Patients in the United States.

We report the genome sequences of three clinical isolates of Tannerella forsythia from the subgingival plaque of periodontitis patients attending clinics at the School of Dental Medicine, University at Buffalo. The availability of these genome sequences will aid the understanding of the pathogenesis of periodontitis

Detecção de cepas de Actinobacillus actinomycetemcomitans de máxima e mínima leucotoxicidade em pacientes com doença periodontal

This study examined the prevalence of highly and minimally leukotoxic Actinobacillus actinomycetemcomitans in patients with periodontal disease. Pooled subgingival plaque samples from 136 patients with some form of periodontal disease were examined. Subjects were between 14 and 76 years of age. Clinical examinations included periodontal pocket depth (PD), plaque index (PI) and bleeding index (BI). The obtained plaque samples were examined for the presence of highly or minimally leukotoxic A. actinomycetemcomitans strains by the polymerase chain reaction (PCR). Chi-square and logistic regression were performed to evaluate the results. Forty-seven subjects were diagnosed with gingivitis, 70 with chronic periodontitis and 19 with aggressive periodontitis. According to chi-square there was no significant correlation detected between PD (chi2 = 0.73), PI (chi2 = 0.35), BI (chi2 = 0.09) and the presence of the highly leukotoxic A. actinomycetemcomitans. The highly leukotoxic A. actinomycetemcomitans strains were correlated with subjects that were 28 years of age and younger (chi2 = 7.41). There was a significant correlation between highly leukotoxic A. actinomycetemcomitans and aggressive periodontitis (chi2 = 22.06). This study of a Brazilian cohort confirms the strong association between highly leukotoxic A. actinomycetemcomitans strains and the presence of aggressive periodontitis.O presente estudo avaliou a prevalência de Actinobacillus actinomycetemcomitans de máxima e mínima leucotoxicidade em indivíduos com doença periodontal. Foram analisadas amostras de placa bacteriana subgengival de 136 indivíduos, entre 14 e 76 anos de idade, com algum tipo de doença periodontal. Os parâmetros clínicos avaliados incluíram profundidade de sondagem (PS), índice de placa bacteriana (IPB) e índice de sangramento gengival (ISG). A presença de amostras de A. actinomycetemcomitans de máxima e mínima leucotoxicidade foi avaliada por reação em cadeia da polimerase (PCR). Os resultados foram analisados empregando-se teste qui-quadrado e análise de regressão logística. Quarenta e sete indivíduos apresentaram gengivite, 70 indivíduos periodontite crônica e 19 indivíduos periodontite agressiva. O teste qui-quadrado não demonstrou correlação significativa entre PS (chi2 = 0,73), IPB (chi2 = 0,35), ISG (chi2 = 0,09) e a presença de amostras de máxima leucotoxicidade. A. actinomycetemcomitans de máxima leucotoxicidade apresentou associação com indivíduos com idade inferior a 28 anos (chi2 = 22,06). Os resultados observados nessa população brasileira confirmam a forte associação existente entre amostras de A. actinomycetemcomitans de máxima leucotoxicidade e periodontite agressiva

Frozen: Thawing and Its Effect on the Postmortem Microbiome in Two Pediatric Cases,

Previous postmortem microbiome studies have focused on characterizing taxa turnover during an undisturbed decomposition process. How coexisting conditions (e.g., frozen, buried, burned) affect the human microbiome at the time of discovery is less well understood. Microbiome data were collected from two pediatric cases at the Wayne County Medical Examiner in Michigan. The bodies were found frozen, hidden in a freezer for an extended time. Microbial communities were sampled from six external anatomic locations at three time points during the thawing process, prior to autopsy. The 16S rRNA V4 gene amplicon region was sequenced using high‐throughput sequencing (Illumina MiSeq). Microbial diversity increased, and there was a distinct shift in microbial community structure and abundance throughout the thawing process. Overall, these data demonstrate that the postmortem human microbiome changes during the thawing process, and have important forensic implications when bodies have been substantially altered, modified, and concealed after death.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138306/1/jfo13419.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138306/2/jfo13419_am.pd

Apolipoprotein E related Co-Morbidities and Alzheimer’s disease

The primary goal of advancement in clinical services is to provide a health care system that enhances an individual’s quality of life. Incidence of diabetes mellitus, cardiovascular disease and associated dementia coupled with the advancing age of the population, have led to an increase in the worldwide challenge to the healthcare system. In order to overcome these challenges prior knowledge of common, reliable risk factors and their effectors is essential. The oral health constitutes one such relatively unexplored but indispensable risk factor for aforementioned co-morbidities, in the form of poor oral hygiene and tooth loss during aging. Behavioural traits such as low education, smoking, poor diet, neglect of oral health, lack of exercise, and hypertension are few of the risk factors that are shared commonly amongst these conditions. In addition, common genetic susceptibility traits such as the apolipoprotein ɛ gene, together with an individual’s life style can also influence the development of co-morbidities such as periodontitis, atherosclerosis/stroke, diabetes, and Alzheimer’s disease. This review specifically addresses the susceptibility of apolipoprotein ε gene allele 4 as the plausible commonality for the etiology of co-morbidities that eventually result from periodontal diseases and ultimately progress to dementia

Mapping the epithelial-cell-binding domain of the Aggregatibacter actinomycetemcomitans autotransporter adhesin Aae

The Gram-negative periodontopathogen Aggregatibacter actinomycetemcomitans (Aa) binds selectively to buccal epithelial cells (BECs) of human and Old World primates by means of the outer-membrane autotransporter protein Aae. We speculated that the exposed N-terminal portion of the passenger domain of Aae would mediate binding to BECs. By using a series of plasmids that express full-length or truncated Aae proteins in Escherichia coli, we found that the BEC-binding domain of Aae was located in the N-terminal surface-exposed region of the protein, specifically in the region spanning amino acids 201–284 just upstream of the repeat region within the passenger domain. Peptides corresponding to amino acids 201–221, 222–238 and 201–240 were synthesized and tested for their ability to reduce Aae-mediated binding to BECs based on results obtained with truncated Aae proteins expressed in E. coli. BEC-binding of E. coli expressing Aae was reduced by as much as 50 % by pre-treatment of BECs with a 40-mer peptide (201–240; P40). Aae was also shown to mediate binding to cultured human epithelial keratinocytes (TW2.6), OBA9 and TERT, and endothelial (HUVEC) cells. Pre-treatment of epithelial cells with P40 resulted in a dose-dependent reduction in binding and reduced the binding of both full-length and truncated Aae proteins expressed in E. coli, as well as Aae expressed in Aa. Fluorescently labelled P40 peptides reacted in a dose-dependent manner with BEC receptors. We propose that these proof-of-principle experiments demonstrate that peptides can be designed to interfere with Aa binding mediated by host-cell receptors specific for Aae adhesins

Visualization and quantification of the oral hygiene effects of brushing, dentifrice use and brush wear using a tooth brushing simulator

Standardized, reproducible brushing regimes were applied to typodonts coated in simulated or biological plaques to assess the effects on tooth cleaning of toothbrush/dentifrice regimens. Replicated typodonts were coated with OccludeTM or GlogermTM indicators to simulate plaque, and brushed reproducibly using a mechanical brushing simulator to compare the cleaning of occlusal surfaces before and after brushing with water or a dentifrice. An in vitro model using salivary inocula to cultivate oral biofilms on typodont surfaces was then developed to evaluate removal of disclosed plaque by new toothbrushes in comparison to toothbrushes with wear equivalent to three months of use. Analyses of typodonts brushed under controlled conditions significantly (p < 0.01) distinguished between brushed and unbrushed surfaces and between the use of water versus dentifrice for the removal of simulated interproximal plaque (p < 0.05). New toothbrushes removed significantly (p < 0.05) more biological plaque from typodont surfaces than brushes that had been worn by repeated brushing. Through controlled and defined brushing of typodonts with simulated and biological plaques, the effectiveness of dental hygiene regimens was compared under reproducible conditions. Data indicate that the cleaning effectiveness of brushing was augmented by the addition of dentifrice and that new brushes were significantly more effective than brushes with substantial wear from previous use