Halomonas dongshanensis sp. nov., isolated from the seawater of Dongshan Island.

A taxonomic study was carried out on strain yzlin-01T, isolated from Dongshan Island seawater. The bacterium was Gram-stain-negative, catalase-positive, oxidase-negative, rod-shaped, and motile by polar flagella. Growth was observed at temperatures of 10-40 °C, at salinities of 0.5-18 %, and at pH of 6-10. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain yzlin-01T belonged to the genus Halomonas, with the highest sequence similarity to Halomonas malpeensis YU-PRIM-29T (96.7 %), followed by Halomonas johnsoniae T68687T (96.4 %) and Halomonas gomseomensis M12T (96.4 %), and other species of the genus Halomonas (93.4-96.3 %). The ANI and digital DNA-DNA hybridization estimate values between strain yzlin-01T and the closest type strain Halomonas malpeensis YU-PRIM-29T were 77.44 and 21.6 %, respectively. The principal fatty acids were summed feature 8 (consisting of C18 : 1 ω7c and/or C18 : 1 ω6c; 55.7 %), C16 : 0 (20.6 %), C12 : 0 3-OH (6.8 %), summed feature 3 (consisting of C16 : 1 ω7c and/or C16 : 1 ω6c; 5.1 %). The G+C content of the chromosomal DNA was 60.0 mol %. The respiratory quinone was identified as Q-9 (100 %). Phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, aminophospholipid, and three unidentified phospholipids were present. Combined genotypic and phenotypic data suggest that strain yzlin-01T represents a novel species within the genus Halomonas, for which the name Halomonas dongshanensis sp. nov. is proposed, with the type strain yzlin-01T (=GDMCC 1.3202T=KCTC 92467T).

[Survey of periodontal health in medical college students after 3 years of periodontal health maintenance].

PURPOSE: To observe and evaluate the status of periodontal disease in young people and the effect of intervention to control the development of periodontal diseases. METHODS: One hundred and fifty-three medical college students were randomly divided into group A (receiving interventions) and group B (no interventions). They were followed up for 3 years. The subjects in group A received oral health education, including selection of the toothbrush, the right way to brush teeth, the use of dental floss and interdental brush. At the same time ,they were given initial periodontal treatment according to the actual situation, and received oral health education, periodontal maintenance treatment, and reinforced plaque control every six months. The changes of debris index (DI), calculus index (CI), probing depth (PD), clinical attachment loss (CAL), bleeding on probing (BOP) and gingival index (GI) before and after interventions were compared. Statistical analysis was performed using SAS 6.12 software package. RESULTS: Three years later, CI and DI in group A declined significantly compared to the baseline (P<0.01), but there was no significant changes in group B (P>0.05). There was significant difference in the changes of PD, BOP and GI between group A and B (P<0.01). Significant difference of the change of CAL between group A and B was also found(P<0.05), CAL in group B was significantly higher than that in group A. CONCLUSIONS: There are positive effects of regular periodontal health maintenance and oral health education on periodontal health.

[The effect of rhAm and EMPs on promoting differentiation of hBMSCs into osteoblasts].

PURPOSE: To compare the effect of recombinant full-length human amelogenin (rhAm) and enamel matrix proteins (EMPs) on differentiation of human bone marrow stromal cells (hBMSCs) into osteoblasts. Meanwhile, to investigate the possible mechanism of rhAm promoting osteogenic differentiation of hBMSCs. METHODS: The hBMSCs were cultured in vitro. The cells were treated with 10 µg/mL rhAm and 200 µg/mL EMPs. The gene and protein expression of Runx2, ALP, Col-I were observed by using RT-PCR and Western blot at different time points. The influence of rhAm and EMPs on mineralization and osteogenesis of hBMSCs were observed by using alkaline phosphatase and alizarin red staining methods. The data was analyzed with SPSS 13.0 software package. RESULTS: Both rhAm and EMPs significantly promoted gene and protein expression of Runx2, ALP and Col-I in hBMSCs. Meanwhile, rhAm and EMPs also facilitated osteogenesis and mineralization of hBMSCs. The effects of two proteins on hBMSCs had no significant difference. CONCLUSIONS: Both 10 µg/mL rhAm and 200 µg/mL EMPs can significantly promote differentiation of hBMSCs into osteoblasts. The rhAm may be used in inducing periodontal tissue regeneration in the future.

Esthetic management of mucogingival defects after excision of epulis using laterally positioned flaps.

Epulis is a benign hyperplasia of the oral soft tissues. Surgical excision always extends to the periosteum and includes scaling of adjacent teeth to remove any possible irritants. The esthetics of the soft tissues may be compromised, however. This article studies three cases in which an immediate laterally positioned flap (LRF) was used to repair mucogingival defects after epulis biopsies. After 24 months, the color and shape of the surgical areas were healthy and stable, nearly complete root coverage was evident, and no lesions reoccurred. For repairing gingival defects after biopsy, LRF appears to be minimally traumatic while promoting esthetic outcomes.

[The effect of hypoxia on proliferation and osteogenic differentiation of periodontal ligament cells].

PURPOSE: To investigate the effect of hypoxia on proliferation and osteogenic differentiation of periodontal ligament cells (PDLCs) in vitro. METHODS: Human PDLCs were isolated and characterized. The proliferation rate of PDLCs under different concentration of CoCl(2) were tested by MTT assay. The PDLCs' osteogenic differentiation were investigated using real-time PCR and Western blot. The date was statistically analyzed with SPSS13.0 software package. RESULTS: Immunocytochemical staining verified that the isolated cells were PDLCs. The proliferation of PDLCs and the expression of alkaline phosphatase (ALP), RUNX2, collagen I were significantly decreased in a dose-dependent manner by 200 µmol/L CoCl(2) and 400 µmol/L CoCl(2). CONCLUSIONS: Hypoxia inhibits proliferation and osteogenic differentiation of human PDLCs.

miRNA-146 negatively regulates the production of pro-inflammatory cytokines via NF-κB signalling in human gingival fibroblasts.

OBJECTIVE: In human gingival fibroblasts (HGFs), TLR4 recognises Pathogen-associated molecular patterns (PAMPs), such as LPS, and subsequently activates downstream signals that lead to the production of pro-inflammatory cytokines. The aim of this study was to explore the mechanisms of LPS-induced miRNA-146 regulation of TLR4 signals in HGFs. MATERIALS AND METHODS: HGFs were treated with Porphyromonas gingivalis (P.g) LPS, the cells were harvested, and kinase phosphorylation levels were detected by western blot. Selective pharmacological inhibitors and agonists were used to block or activate the relevant kinases, miRNA-146a/b expression levels were detected by real-time PCR, and IL-1, IL-6, and TNF-α production were measured by enzyme-linked immunosorbent assays (ELISA). A luciferase reporter plasmid containing miRNA-146a/b promoter was tested in terms of p50/p65 regulation. RESULTS: After P.g LPS treatment, NF-κB and Erk1/2 were strongly activated in HGFs. miRNA-146a/b, IL-1, IL-6 and TNF-α levels were down-regulated when NF-κB inhibitor was used. p50/p65 strongly activated miRNA-146a/b promoter as measured with the luciferase assay. CONCLUSION: In TLR4 signalling in HGFs, both miRNA-146a and miRNA-146b are downstream targets of NF-κB, but not of AP-1 signalling. miRNA-146a/b expression was specifically dependent on NF-κB but not Erk1/2 or JNK signalling.

[Effects of rhAm on attachment, proliferation and immigration of human fibroblasts].

PURPOSE: To compare the effects of 25 kDa full-length rhAm and porcine EMPs on cell behaviors of human periodontal ligament fibroblasts (HPDLF) and foreskin fibroblasts(HFF). METHODS: rhAm was induced by BL21/pET28a-His-SUMO-rhAm express system, and 25 kDa full-length rhAm was analyzed by SDS-PAGE and Western blot. EMPs were extracted by acetic acid method. HPDLF and HFF were cultured in vitro. The cells were treated with rhAm and EMPs at different concentrations. The cell adhesion, proliferation and migration assays were qualitatively analyzed. The data was statistically analyzed with SAS 5.0 software package. RESULTS: 10-20 µg/mL rhAm significantly promoted the adhesion, proliferation and migration of HPDLF and HFF (P<0.05), but no significant difference between two proteins was found (P>0.05). CONCLUSIONS: 25 kDa rhAm and EMPs shows similar biological effects on fibroblast, which indicates that rhAm may play an important role in the periodontal regeneration through the activation of fibroblasts.

Genistein regulates the IL-1 beta induced activation of MAPKs in human periodontal ligament cells through G protein-coupled receptor 30.

Periodontal ligament (PDL) cells are fibroblasts that play key roles in tissue integrity, periodontal inflammation and tissue regeneration in the periodontium. The periodontal tissue destruction in periodontitis is mediated by host tissue-produced inflammatory cytokines, including interleukin-1ß (IL-1ß). Here, we report the expression of G protein-coupled receptor 30 (GPR30, also known as G protein-coupled estrogen receptor 1 GPER) in human PDL cells and its regulation by IL-1ß. IL-1ß-induced GPR30 expression in human PDL cells leads to the activation of multiple signaling pathways, including MAPK, NF-κB and PI3K. In contrast, genistein, an estrogen receptor ligand, postpones the activation of MAPKs induced by IL-1ß. Moreover, the inhibition of GPR30 by G15, a GPR30-specific antagonist, eliminates this delay. Thus, genistein plays a role in the regulation of MAPK activation via GPR30, and GPR30 represents a novel target regulated by steroid hormones in PDL cells.