The Porphyromonas gingivalis/host interactome shows enrichment in GWASdb genes related to Alzheimer’s disease, diabetes and cardiovascular diseases

Periodontal disease is of established aetiology in which polymicrobial synergistic ecology has become dysbiotic under the influence of Porphyromonas gingivalis. Following breakdown of the host’s protective oral tissue barriers, P. gingivalis migrates to developing inflammatory pathologies that associate with Alzheimer’s disease (AD). Periodontal disease is a risk factor for cardiovascular disorders (CVD), type II diabetes mellitus (T2DM), AD and other chronic diseases, whilst T2DM exacerbates periodontitis. This study analysed the relationship between the P. gingivalis/host interactome and the genes identified in genome-wide association studies (GWAS) for the aforementioned conditions using data from GWASdb (P<1E-03) and, in some cases, from the NCBI/EBI GWAS database (P< 1E-05). Gene expression data from periodontitis or P. gingivalis microarray was compared to microarray datasets from the AD hippocampus and/or from carotid artery plaques. The results demonstrated that the host genes of the P. gingivalis interactome were significantly enriched in genes deposited in GWASdb genes related to cognitive disorders, AD and dementia, and its co-morbid conditions T2DM, obesity, and CVD. The P. gingivalis/host interactome was also enriched in GWAS genes from the more stringent NCBI-EBI database for AD, atherosclerosis and T2DM. The misregulated genes in periodontitis tissue or P. gingivalis infected macrophages also matched those in the AD hippocampus or atherosclerotic plaques. Together, these data suggest important gene/environment interactions between P. gingivalis and susceptibility genes or gene expression changes in conditions where periodontal disease is a contributory factor

Halitosis in obese patients and those undergoing bariatric surgery

Background: Patients undergoing bariatric surgery often complain of bad breath. However, the relationship between bariatric surgery and halitosis is relatively unknown. The purpose of the present study was to evaluate and compare the occurrence of halitosis among patients before and after a specific type of bariatric surgery, Roux-en-Y gastric bypass, and its relationship with the tongue coating index, plaque index, and salivary flow rate. Methods: A total of 62 patients with good oral health and in treatment for obesity at the walk-in clinic of Santa Casa Hospital, Belo Horizonte, Brazil, were selected. Of this sample, 31 were bariatric surgery candidates (control group) and 31 had already undergone Roux-en-Y gastric bypass surgery (case group). After completing a questionnaire, all patients underwent an oral clinical examination. Halitosis was measured using an organoleptic scale and a portable sulfide monitor. Results: The Spearman correlation demonstrated a strong positive relation between the organoleptic rates and the concentration of volatile sulfur compounds determined using the sulfide monitor (r(s) = .58; P = .0001). No difference was found in the prevalence of halitosis between the 2 groups (P = .48). Only the salivary flow rate was significantly reduced in the control group compared with the case group (P = .02). In the case group, the concentration of volatile sulfur compounds correlated negatively with the salivary flow rate (P = .04) and positively with the tongue coating index (P = .005). The tongue coating index was significantly increased in those patients who did not brush the tongue (P < .04) and who had had episodes of vomiting (P = .02). Conclusion: These data suggest that no significant association exists between halitosis and Roux-en-Y gastric bypass. However, they do highlight the possible effect of this surgery on the oral cavity. (Surg Obes Relat Dis 2013;9:315-322.) (C) 2013 American Society for Metabolic and Bariatric Surgery. All rights reserved.9231532

Global patterns of tree density are contingent upon local determinants in the world’s natural forests

Previous attempts to quantify tree abundance at global scale have largely neglected the role of local competition in modulating the influence of climate and soils on tree density. Here, we evaluated whether mean tree size in the world’s natural forests alters the effect of global productivity on tree density. In doing so, we gathered a vast set of forest inventories including >3000 sampling plots from 23 well-conserved areas worldwide to encompass (as much as possible) the main forest biomes on Earth. We evidence that latitudinal productivity patterns of tree density become evident as large trees become dominant. Global estimates of tree abundance should, therefore, consider dependencies of latitudinal sources of variability on local biotic influences to avoid underestimating the number of trees on Earth and to properly evaluate the functional and social consequences.ISSN:2399-364

Bioceramic/Poly (glycolic)-poly (lactic acid) composite induces mineralized barrier after direct capping of rat tooth pulp tissue

The aim of this study was to observe the histopathological pulp response following direct pulp capping of mechanically exposed teeth in rats with a composite of beta-tricalcium phosphate-hydroxyapatite bioceramic (BC) and poly (glycolic)-poly (lactic acid) (PLGA) material or a calcium hydroxide [Ca(OH)2] material, compared to BC alone and a negative control of water. Pulp of the maxillary molars was exposed, followed by capping with the experimental material. The pulpal tissue response was assessed post-operatively at 1, 7, 14 and 30 d, followed by histological analysis. The Ca(OH)2 group exhibited severe acute inflammatory cell infiltration at day 14. However after 30 d, a new hard tissue with macro porous obliteration of the pulp chamber and a characteristic necrotic area had appeared. BC and Ca(OH)2 capping were associated with moderate inflammation and dentinal bridge similar. Meanwhile, in the BC/PLGA composite group, there was moderate inflammatory infiltrate and formation of a dense and complete dentinal bridge. In conclusion, the BC/PLGA composite material showed a large zone of tertiary dentin, and effectively reorganized the dentin-pulp complex