A preliminary study on bacterial composition in the subgingival plaque of woman with periodontitis during pregnancy and menopause

Aim: The aim of the present study was to explore the bacterial composition in subgingival plaque of females with periodontitis during pregnancy and menopause stages using 16S ribosomal RNA (rRNA) gene pyrosequencing approach.Methodology: Subgingival plaque was collected from four woman volunteers (healthy, periodontitis, periodontitis at pregnancy and periodontitis at menopause). The microbial community composition was analyzed by 454/Roche GS FLX chemistry pyrosequencing approach using the variable (V1-V3) region of the 16S rRNA gene. Pyrosequencing reads were sorted to get the clean reads that were annotated against the EzBioCloud data base for taxonomic classification. Operational Taxonomic Units (OTUs) were assigned and shared, and subsequently identified using CLCOMMUNITY software. Results: Pyrosequencing yielded 13,939 sequences comprising of 13 phyla, 124 genera, and 372 species. The predominant microbial phyla in subgingival plaque of all woman volunteers included Firmicutes, Actinobacteria, Fusobacteria, Bacteroidetes, and Proteobacteria. In the healthy volunteer, Streptococcus (52.4%) formed the predominant genus while in woman with periodontitis Streptococcus (24.6%) and Fusobacterium (11.7%) predominated. In the periodontitis volunteer with pregnancy, the predominant genus included Streptococcus (25.8%) and Fusobacterium (22.4%), whereas volunteer with menopause, the gingivitis was associated with genus Alloprevotella (19.5%), Leptotrichia (14.3%), Fusobacterium (12.3%), and Porphyromonas (12.0%). Interpretation: This study proves on preliminary basis that the subgingival microbiome of woman with periodontitis at pregnancy or menopause tend to differ from that of healthy woman, and these species included certain periodontal pathogens such as Fusobacterium nucleatum and Porphyromonas gingivalis

Seasonal variations of marine algal community in the vicinity of Uljin nuclear power plant, Korea.

Three marine algal sites were examined seasonally in an area of thermal discharge from the Uljin nuclear power plant in Korea to assess possible impacts from thermal stress. Quadrat samples were taken at three sites: cooling water intake, outfall and Chukbyon. The degree of wave exposure increased from intake, outfallto Chukbyon. Percent cover and biomass were response variables. All sites were, by numbers red algae, followed by brown and green algae. Over the year the maximum species diversity was also found at the Chukbyon (2.39), but the minimal one (1.67) was observed at the outfall. Seasonally generally among algal form-functional groups, filamentous and coarsely branched algae were most abundant throughout the year at the three sites. The numberof species in the jointed calcareous groups increased remarkably at the outfall. Based on these results, species richness appears tobe strongly affected by wave exposure and thermal stress. The higher proportion of calcareous form groups at the outfall sites indicates that these species are better adapted morphologically to thermal stress such as high temperatures.