17-β estradiol promotes the expression of interleukin-6 in human periodontal ligament cells infected with Porphyromonas gingivalis / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effects of 17-β estradiol (E(2)) and Porphyromonas gingivalis (Pg) W83 on the expression of interleukin (IL)-6 and IL-8 in human periodontal ligament cells (hPDLC).</p><p><b>METHODS</b>Primary cultures of hPDLC were established and the cells of passage four were treated with 10(-10) mol/L E(2), 10(-7) mol/L E(2) or PgW83 individually or E(2) combined with PgW83. The expression levels of IL-6 and IL-8 protein at 12 h and 24 h were measured with enzyme-linked immunosorbent assay and the levels of mRNA at 24 h were detected with real-time reverse transcriptase polymerase chain reaction.</p><p><b>RESULTS</b>The expression level of IL-6 reached (2482.88 ± 26.53) ng/L in hPDLC treated with Pg at multiplicity of infection (MOI) of 100 for 24 h, which was significantly higher than that in hPDLC treated with Pg at MOI of 10:1 [(734.09 ± 87.90) ng/L, P = 0.000], the controls [(425.8 ± 77.25) ng/L, P = 0.000] and that in hPDLC treated with Pg at MOI of 100 for 12 h [(1157.50 ± 234.65) ng/L, P = 0.000]. The expression level of IL-8 reached (4965.81 ± 1072.55) ng/L in hPDLC treated with Pg at MOI of 100 for 24 h, which was significantly higher than that in hPDLC treated with Pg at MOI of 10 [(803.51 ± 162.08) ng/L, P = 0.007], the controls [(400.75 ± 2.27) ng/L, P = 0.005] and that in hPDLC treated with Pg at MOI of 100 for 12 h [(1431.12 ± 82.78) ng/L, P = 0.001]. E(2) did not show remarkable effect on the expressions of IL-6 and IL-8. E(2) combined with Pg (MOI = 100:1) significantly promoted the expression levels of IL-6 at 24 h while did not influence those of IL-8. The relative mRNA level of IL-6 in hPDLC treated with 10(-10) mol/L E(2) or 10(-7) mol/L E(2) combined with Pg were 0.49 ± 0.15 (P = 0.021)and 0.53 ± 0.16 (P = 0.036) individually, which were significantly higher than that treated with Pg alone, 0.19 ± 0.06. The protein level of IL-6 in hPDLC treated with 10(-10) mol/L E(2) or 10(-7) mol/L E(2) combined with Pg were (5512.66 ± 1022.07) ng/L (P = 0.012) and (6988.78 ± 2279.13) ng/L (P = 0.000) individually, which were significantly higher than that treated with Pg alone, (3138.46 ± 183.72) ng/L.</p><p><b>CONCLUSIONS</b>PgW83 significantly increased the expression levels of IL-6 and IL-8 in hPDLC in a dose-and time-dependent manner. Without the infection of periodontal pathogens, estrogen may exert no effect on the expression of IL-6 and IL-8 while it may promote the expression of IL-6 in hPDLC when combined with Pg, which may in turn promote the process of periodontal inflammation.</p>

Effect of PG0839 gene of Porphyromonas gingivalis on inflammatory cytokine in human oral epidermoid carcinoma KB cell / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of PG0839 gene form Porphyromonas gingivalis (Pg) on inflammatory cytokine expression in human oral epidermoid carcinoma KB cell.</p><p><b>METHODS</b>A mutant in the PG0839 gene of Pg was created by insertional inactivation. Group 1 was chanllenged with PgW83 strain, group 2 with PG0839-defective mutant, and the control group with Dulbecco's modified Eagle's medium only. KB cells were co-cultured with presence of bacteria for 24 h. At the time point of 0.5, 2, 6, 12 and 24 h, cells were stored in Trizol. The mRNA expression of interleukin-1β (IL-1β) and Toll like recepector-4 (TLR-4) was examined by reverse transcription polymerase chain reaction.</p><p><b>RESULTS</b>At 2 h and 6 h, IL-1β mRNA expression was lower in group 2 than in group 1 (2 h: 0.31 ± 0.11 versus 0.95 ± 0.48, P < 0.05; 6 h: 0.57 ± 0.20 versus 1.29 ± 0.55, P < 0.05). At 0.5 h and 6 h, TLR-4 mRNA expression was lower in group 2 than in group 1 (0.5 h: 0.20 ± 0.09 versus 0.58 ± 0.09, P < 0.05; 6 h: 0.34 ± 0.04 versus 0.71 ± 0.18, P < 0.05).</p><p><b>CONCLUSIONS</b>PG0839 gene may play an important role in Pg-induced inflammatory effects of KB cell.</p>

Study of serological biochemistry index of chronic periodontitis / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of serum biochemistry on the development of periodontitis.</p><p><b>METHODS</b>225 participants without any system disease were involved in the study. Case group consist of 145 chronic peri-odontitis and was divided into gentle group (clinical attachment loss < 3 mm), moderate and severe group(clinical attachment loss > or = 3 mm). Control group consist of 80 periodontal healthy persons. Peripheral blood sample was obtained from each subject by venipuncture. Serum chemistry variables including glucose, lipid and calcium were analyzed. SPSS 12.0 software package was adopted to analyze the investigation results.</p><p><b>RESULTS</b>There's no statistically significant difference of serum, lipid and calcium between case group and control group (P > 0.05). But case group had a higher percentage of people with abnormal glucose, lipid and calcium than control group (P < 0.05). Moderate and severe group had a significantly higher serum glucose, triglyceride and lipoproteins-cholesterol than gentle group (P < 0.05).</p><p><b>CONCLUSION</b>Abnormal level of serum glucose, lipid and calcium may increase the affectability of host to periodontitis and promote the inflammation in paradentium.</p>

Screening of lipoprotein genes of Porphyromonas gingivalis in chronic periodontitis patients / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To screen PG0717, PG0183 and PG2135 gene of Porphyromonas gingivalis (Pg) in subgingival plaque of the chronic periodontitis patients and periodontally healthy subjects and to investigate the relationship of these genes and periodontal clinical parameters.</p><p><b>METHODS</b>Forty-one chronic periodontitis patients and 76 periodontally healthy individuals were included. Clinical parameters were measured and recorded by a single examiner, which included bleeding on probing (BOP), attachment loss (AL), probing depth (PD), and tooth mobility (TM). Subgingival plaque samples were taken by sterile subgingival curette. The three genes, which were present in PgW83 but absent from PgATCC33277 were labeled with Cy5 and used as probes in DNA microarray hybridization. The PG0717, PG0183 and PG2135 gene in affected region, normal region and healthy individuals of Pg was examined.</p><p><b>RESULTS</b>The detecting rate of PG0717, PG0183 and PG2135 was 90% (18/20), 70% (14/20) and 70% (14/20) respectively in affected region, 60% (12/20), 45% (19/20) and 40% (8/20) respectively in normal region and 55% (11/20), 25% (5/20), 30% (6/20) in Pg of healthy individuals. The detecting rate of PG0717, PG0183 and PG2135 was significantly different between the affected region and the healthy individuals (P < 0.05).</p><p><b>CONCLUSIONS</b>The Pg with genes of PG0717, PG0183, PG2135 was more pathogenic.</p>

A survey on the periodontal status in type 2 diabetic patients / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the type 2 diabetic patient's periodontal condition and to analyze the influencing factors of periodontitis.</p><p><b>METHODS</b>A total of 182 type 2 diabetic patients were included in the survey and requested to fill out a questionnaire, and their periodontal status was evaluated by measuring probing depth (PD), attachment level (AL), sulcus bleeding index (SBI), simplified oral hygiene index (OHI-S).</p><p><b>RESULTS</b>The prevalence of periodontitis in this group of patients was 96.7% (176/182), including 20 patients with mild periodontitis, 156 with moderate to advanced periodontitis. The mean PD and AL of the 182 patients were (2.92 +/- 0.67) mm and (2.87 +/- 1.31) mm. At least one tooth was lost in 57.1% (104/182) of the patients. The factors related to periodontitis were age, gender, smoking, living in town or country, and 2 h plasma glucose of oral glucose tolerance test (OGTT). There was no relationship between the severity of periodontitis and education level. The majority of patients did not receive any periodontal therapy.</p><p><b>CONCLUSIONS</b>Periodontal status was bad in patients with type 2 diabetes. It is important to develop an education program on oral health for type 2 diabetic patients.</p>

Relationship of porphyromonas gingivalis PG0717 gene with chronic periodontitis / 华西口腔医学杂志

<p><b>OBJECTIVE</b>The aim of the present study was to investigate PG0717 gene of Porphyromonas gingivalis (P. gingivalis) in subgingival plaque of the chronic periodontitis patients and periodontal healthy subjects, and to find out the relationship of detection rate of PG0717 and periodontal clinical parameters.</p><p><b>METHODS</b>A total of 540 subgingival plaque samples were collected from 180 subjects including chronic periodontitis (CP) patients (n=90) and periodontal healthy individuals (n=90). The periodontal clinical parameters including probing depth (PD), clinical attachment loss (CAL), and bleeding on probing (BOP) were estimated by Florida probe. The extracted DNA samples of P. gingivalis positive was amplified with the sequence specific primers designed to obtain the PG0717 gene.</p><p><b>RESULTS</b>In subgingival plaque of P.gingivalis positive, the detection rate of PG0717 in CP group was significantly higher than that in periodontal healthy subjects (56.22% versus 41.27%, chi2=4.50, P<0.05). The detection rate of PG0717 in CP group showed the increasing tendency in accordance with the depth of PD and CAL. A higher detection rate of PG0717 was observed in the sites of BOP positive than that in BOP negative (57.73% versus 14.29%, chi2=42.01, P<0.01).</p><p><b>CONCLUSION</b>The findings suggest that the PG0717 gene may influence the virulence of P. gingivalis.</p>

Study on Porphyromonas gingivalis colonization in patients with periodontitis after periodontal initial therapy / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To examine Porphyromonas gingivalis (Pg) in subgingival plaque of the patients with periodontitis and to find out the rules of Pg colonization after periodontal initial treatment.</p><p><b>METHODS</b>A total of 1620 subgingival plaque samples were collected from 180 subjects including chronic periodontitis (CP) patients (n = 90), and aggressive periodontitis (AgP) patients (n = 90) in different periods of periodontal initial therapy-the baseline, 6 weeks, and 12 weeks after treatment. The following periodontal clinical parameters were recorded with Florida probe at sampled sites: probing depth (PD), clinical attachment loss (CAL), and bleeding on probing (BOP). Quantities of Pg were examined by AmpliFluor endpoint quantitative polymerase chain reaction.</p><p><b>RESULTS</b>At the 6th week of periodontal initial therapy, there were 61 (22.6%) and 66 (24.4%) Pg increased sites respectively, in which no significant difference was detected (P > 0.05). At baseline of periodontal initial therapy, more severe periodontal clinical parameters of Pg increased sites were observed than those of Pg stationary sites. At the 12th week, however, there were 96 (35.6%) and 18 (6.7%) Pg increased sites respectively, significant difference detected (P < 0.05). At 6th week of periodontal initial therapy, more severe periodontal clinical parameters of Pg increased sites were observed than those of Pg stationary sites.</p><p><b>CONCLUSIONS</b>Pg colonization in AgP and CP patients started 6 weeks after periodontal initial therapy, but the recolonization pattern was different between these two groups of patients. Severe periodontitis sites in baseline seemed to place them at risk of Pg colonization after periodontal initial therapy.</p>

Cloning of CTB-PROIN fusion gene and its expression in Escherichia coli / 生物工程学报

A fusion gene CTB-PROIN, in which Proinsulin gene was fused to the 3' end of CTB gene by a hinge peptide 'GPGP', was constructed and cloned into pET-30a(+) to obtain a prokaryotic expression vector pETCPI. Subsequently the recombinant plasmid pETCPI was transformed into E. coli stain BL21 (DE3). After induced by IPTG, the expression product was analyzed by sodium dodecyl sulphate-polyacrylamide gel (15%) electrophoresis (SDS-PAGE), and its result indicated that the recombinant protein CTB-PROIN was expressed and accumulated as inclusion bodies. The recombinant CTB-PROIN protein accumulated to the level of 25% of total bacterial proteins. After inclusion bodies was denaturalized and refolded in vitro, significant assembly of monomers had occurred, and the recombinant protein represented assembled pentamers. The results of western blotting analysis also demonstrated that the fusion protein could be recognized by the anti-CT and anti-insulin antibody, respectively. In addition, the result of the CTB-PROIN-GM1 binding assay, that the protein could bind to monosialoganglioside specifically, showed it possesed biological activity in vitro. These results provided the possibility of developing a cheaper and more efficient oral vaccine for type I diabetes using such constructs.