[Porphyromonas gingivalis persisters induce the immuno-inflammatory responses in macrophages by upregulating the forkhead box1 signaling pathway].

Objective: To investigate the effects of Porphyromonas gingivalis (Pg) persisters (Ps) on immuno-inflammatory responses in macrophages, and to explore the underlying mechanisms. Methods: Pg cells were cultured to the stationary phase (72 h), and subsequently treated by high concentration of metronidazole at 100 mg/L, amoxicillin at 100 mg/L and the combination of them for different time period, named as metronidazole group, amoxicillin group and (metronidazole+amoxicillin) group. Pg cells without management were used as blank control. The survival profile of PgPs cells was measured by colony-forming unit assay. The living state of PgPs was observed by Live/Dead staining. Then, Pg and metronidazole-treated PgPs (M-PgPs) were used to treat macrophages, named as Pg group and M-PgPs group. Transmission electron microscopy (TEM) was used to observe the bacteria in the macrophages. The expression levels of proinflammatory cytokines in macrophages were determined by real-time fluorescence quantitative PCR and enzyme-linked immunosorbent assay. The location of forkhead box 1 (FOXO1) was detected by confocal immunofluorescence microscopy. After inhibiting or enhancing the FOXO1 expressions using inhibitors (Fi) or activators (Fa) respectively, the macrophages were treated with Pg and M-PgPs, divided as Blank group, Pg group, M-PgPs group, Fi group, (Fi+Pg) group, (Fi+M-PgPs) group, Fa group, (Fa+Pg) group and (Fa+M-PgPs) group. Then, the expression pattens of proinflammatory cytokines were assessed. Results: Remarkable number of lived PgPs was observed, both in planktonic culture and Pg biofilms either treated with metronidazole, amoxicillin or both, and those persisters could form new colonies. Pg and M-PgPs were able to enter into the macrophages and the protein expression levels of interleukin (IL)-1ß, IL-6, IL-8 and tumor necrosis factor-α (TNF-α) [Pg group: (2 392±188), (162±29), (5 558±661), (789±155) µg/L; M-PgPs group: (2 415±420), (155±3), (5 732±782), (821±176) µg/L)] were significantly upregulated than those in Blank group [(485±140), (21±9), (2 332±87), (77±7) µg/L] (P<0.01). Moreover, Pg and M-PgPs could facilitate the nuclear translocation and accumulation of FOXO1. In addition, the relative mRNA expression levels of FOXO1, BCL6 and KLF2 were upregulated when compared to Blank group (P<0.05). Furthermore, the protein expression levels of IL-1ß, IL-6, IL-8 and TNF-α in Fi+Pg group [(1 081±168), (70±8), (1 976±544), (420±47) µg/L] were remarkably lower than Pg group [(4 411±137), (179±6), (5 161±929), (934±24) µg/L] (P<0.05). Similarly, the protein expression levels of IL-1ß, IL-6, IL-8 and TNF-α in Fi+M-PgPs group [(1 032±237), (74±10), (1 861±614), (405±32) µg/L] were remarkably lower than M-PgPs group [(4 342±314), (164±17), (4 438±1 374), (957±25) µg/L] (P<0.05). On the contrary, the protein expression levels of IL-1ß, IL-6, IL-8 and TNF-α in Fa+Pg group [(8 198±1 825), (431±28), (8 919±650), (2 186±301) µg/L] and Fa+M-PgPs group [(8 159±2 627), (475±26), (8 995±653), (2 255±387 µg/L) were both significantly higher than Pg group and M-PgPs group, respectively (P<0.05). Conclusions: PgPs are highly tolerant to metronidazole and amoxicillin. The M-PgPs could enhance the immuno-inflammatory responses in macrophages by upregulating the FOXO1 signaling pathway, while this effect exhibits no significant difference with Pg.

Limb-salvage treatment of malignant tumors of the limbs.

The aim of this study was to explore the clinical efficacy of limb-salvage therapy for malignant bone tumors of the limbs using two surgical methods. This investigation presents a retrospective study of malignant bone tumors of the limbs in 42 patients. Participants were divided into two groups: group A of 25 patients who were treated with artificial prosthesis replacement, and group B of 17 patients treated with bone inactivation. By collection of clinical data, the survival rate, surgical complications, quality of life, pain relief and postoperative limb function following artificial prosthesis replacement and tumor inactivation were comprehensively evaluated in patients with malignant bone tumors of the limbs. Group A had significantly higher Karnofsky quality of life scores compared to group B after six months (P=0.027). The Enneking scores of limb functions in group A were significantly higher than those of group B (P=0.022). In group A the postoperative limb function score was good and excellent in 92% and in group B in 64.7%. There were significantly more postoperative complications in group B compared with group A (P=0.027), but no significant difference in the recurrence rate in the two group (P=0.976). The study results can provide reference for surgical treatment of the patients with malignant bone tumors.

Effect of branched chain amino acids on perioperative temperature, glucose level and fat metabolism in patients with gastrointestinal tumors.

This study aimed to investigate the effect of branched chain amino acids (BCCAs) on perioperative temperature, glucose and fat metabolism in patients with gastrointestinal tumors. Fifty-six patients undergoing gastrointestinal tumor surgery were included in the study and randomly divided into two groups of 28 patients each: an experimental and a control group. During surgery, the experimental group received 5.64mL·Kg-1·h-1(4KJ·Kg-1·h-1) of BCCAs intravenously, through an infusion pump, and the control group received an equal volume of NaCl 0.9%. Vital signs were continuously monitored during the operation. Nasopharynx temperature levels of glucose, insulin, free fatty acid and ketone bodies in the blood were determined 30 min before anesthesia (t 0), after anesthesia and before surgery (t 1), 30 min after the start of surgery (t 2), 2 h after start of surgery (t 3) and 1 h after the end of surgery (T4). Patients’ shivering intensity (Wrench grading) and pain degree [Visual analogue scale (VAS)]) were estimated 1 h after the endotracheal tube was removed. Nasopharynx temperature was decreased (p less than 0.05) in both groups after anesthesia induction, while 1 h after the tube was removed it was higher in the experimental group than the control group (p less than 0.05); compared with pre-surgery values, blood glucose levels were increased during surgery in both groups, but the experimental group had a lower increasing trend compared to the control group, though without statistical significance (p>0.05). Insulin levels were significantly different between the two groups at all time-points during surgery (p less than 0.05). However, the rising trend of the experimental group was more dramatic during the period from t 0 to t 3. One hour after surgery (t 4), the insulin levels varied, but still at higher levels than pre-surgery, with a significant difference (p less than 0.05); levels of free fatty acids had a downward trend in both groups, and levels in the experimental group continued to decline until 1 h after surgery. Patients who received branched chain amino acids had less temperature decrease during surgery. Moreover, blood glucose levels were not increased, which limits fat mobilization and leads to production of ketone bodies, reduces the shivering and its intensity after surgery.

Effect of dexmedetomidine on stress reactions and cellular immune function of patients in perioperative period following radial resection for rectal carcinoma.

The study aimed to assess the effects and the further mechanism of action of dexmedetomidine with regard to stress reactions and cellular immune function of patients during the perioperative period following radical resection for rectal carcinoma. A total of 36 patients with rectal carcinoma were selected for radical resection under general anesthesia. The patients were divided into two groups, namely an experimental and a control group. In the experimental group (dexmedetomidine group) 1 µg/ kg/bw dexmedetomidine was injected intravenously 10 min prior to the induction of general anesthesia, and then infusion was carried out at a rate of 0.2 µg·kg-1·h-1 for 30 min prior to the end of surgery. With regard to the control group, the same amount of normal saline (NS) was infused with the same method as the experimental group. Controlled intravenous analgesia was conducted following surgery to all of the patients. Regarding the effect of dexmedetomidine on the reaction of stress, a decrease of VAS scores was noted in the experimental group following extubation compared with the control group (P less than 0.05). Furthermore, a significant decrease in the consumption of morphine in the first 24 h was observed that was accompanied by a decrease of plasma cortisol levels at 6 and 24 h following surgery compared with the control group. The levels of IFN-γ/IL-10 in the experimental group were lower than those of the control group (P less than 0.05). The percentages of CD8+ and CD4+/CD8+ cells in the experimental group were increased compared with those of the control group (P less than 0.05). By infusing dexmedetomidine continuously, stress reactions during the perioperative period were significantly decreased, whereas the analgesic effects of opioid were increased.

Subgingival glycine powder air-polishing as an additional approach to nonsurgical periodontal therapy in subjects with untreated chronic periodontitis.

BACKGROUND AND OBJECTIVE: Glycine powder air-polishing (GPAP) is an alternative approach to removing subgingival plaque biofilms for effective periodontal therapy. This study aimed to investigate the effect of subgingival GPAP as an additional approach to nonsurgical periodontal treatment in subjects with chronic periodontitis. MATERIAL AND METHODS: Twenty-seven nonsmoking subjects were recruited. Two quadrants in each subject were randomly assigned, according to a split-mouth design, to receive scaling and root planing (SRP) and GPAP (Test group) or SRP and air flushing with water (Control group) at sites with probing depth ≥5 mm. Clinical parameters, gingival crevicular fluid volumes and the concentrations of interleukin-1ß and interleukin-1ra in gingival crevicular fluid were measured at baseline and 1, 3 and 6 months after the treatments. RESULTS: At baseline, no statistically significant difference in periodontal and gingival crevicular fluid parameters was found between the Test and Control groups. Overall, the periodontal conditions of all subjects showed significant improvement after the treatments. Notably, the Test group showed greater reduction in gingival crevicular fluid volume (0.37 ± 0.26 µL) than the Control group (0.23 ± 0.30 µL) at 3 months (P < .05). The gingival crevicular fluid levels of interleukin-1ß and interleukin-1ra showed a significant decrease in both groups at 6 months, and no significant difference was found between the groups. CONCLUSION: These preliminary results suggest that GPAP, as an additional approach to nonsurgical periodontal treatment, may be beneficial for the short-term improvement of subclinical inflammation when measured by gingival crevicular fluid volume. Further longitudinal studies with larger sample sizes are required to clarify the exact benefits of GPAP treatment for controlling inflammation and maintaining long-term periodontal health.

Relationship between genetic variants of ACE2 gene and circulating levels of ACE2 and its metabolites.

WHAT IS KNOWN: Angiotensin-converting enzyme 2 (ACE2) plays an important role in the development of essential hypertension (EH). Genetic factors remarkably influence circulating ACE2 level. OBJECTIVE: Because heritability had remarkable effects on circulating ACE2, we designed this study to shed light on whether circulating levels of ACE2, angiotensin-(1-7) and angiotensin-(1-9) were linked to single nucleotide polymorphisms (SNPs) and haplotypes in ACE2 gene. METHODS: A total of 213 patients with newly diagnosed mild to moderate EH were enrolled in the present study. Four ACE2 tag SNPs (rs2074192, rs4646171, rs4646155 and rs2106809) were genotyped, and major haplotypes consisting of these 4 SNPs were reconstructed for all subjects. Circulating levels of ACE2, angiotensin-(1-7) and angiotensin-(1-9) were measured using enzyme-linked immunosorbent assay. RESULTS: In female subjects, linear regression analysis suggested that rare alleles of ACE2 rs2074192 and rs2106809 were associated with reduced circulating angiotensin-(1-7) levels (P=.007 and P=.006, respectively). ACE2 haplotype CAGC was associated with elevated circulating angiotensin-(1-7) levels (P=.03) whereas TAGT was associated with reduced circulating angiotensin-(1-7) levels in females (P<.001). Univariate linear regression analysis revealed that circulating ACE2 levels were positively associated with systolic blood pressure (P=.02), mean arterial pressure (P=.02) and serum creatinine (P<.001) in females whereas circulating ACE2 levels were positively associated with age (P<.001) and serum creatinine (P<.001) in males. WHAT IS NEW AND CONCLUSION: ACE2 SNPs and haplotypes are associated with circulating angiotensin-(1-7) levels. ACE2 genetic variants may be the determinants of circulating angiotensin-(1-7) levels in hypertensive females.

Sensitization of TRAIL-resistant cervical cancer cells through combination of TRAIL and fucoxanthin treatments.

OBJECTIVE: Cervical cancer, the second most common cause of cancer death in women worldwide, is a malignant neoplasm arising from cells originating in the cervix uteri. Currently, surgery combined with chemo- and radiotherapy is the major therapeutic approach for women with early-stage cervical cancer. However, recurrent cervical cancers from acquired chemo-resistance remain a major cause of therapeutic failure. MATERIALS AND METHODS: In this study, we assessed the effects of the combination of TRAIL with fucoxanthin, which has been reported to suppress the cervical cancer cells growth on the cervical cancer treatments. HeLa cells, SiHa cells, and CaSki cells were used as in vitro model. Mice xenograft was used as in vivo model. TRAIL-resistant cells were generated from CaSki cell line. The activity of PI3K/Akt pathway was detected by Western blot. Cell viability was measured by MTT assay. RESULTS: We observed TRAIL-resistant cervical cancer cells were more sensitive to fucoxanthin treatments. By establishing a TRAIL-resistant cell line from CaSki, we found the TRAIL-resistant cells showed upregulated PI3K/Akt pathway. Moreover, CaSki TRAIL-resistant cells were more sensitive to the combination of TRAIL with either Akt inhibitor or fucoxanthin than treatment with TRAIL or fucoxanthin alone. Our in vitro and in vivo xenograft experiments demonstrate that the combination of TRAIL with fucoxanthin showed synergistically inhibitory effects on cervical cancer cells. CONCLUSIONS: The findings of this study suggest that the combined use of fucoxanthin and TRAIL might be a useful strategy against TRAIL-resistant cervical cancer.

The gingival biotype in a cohort of Chinese subjects with and without history of periodontal disease.

OBJECTIVE: The present study aimed to determine the gingival biotype in Chinese subjects with and without a history of periodontal disease. MATERIAL AND METHODS: Thirty periodontally healthy subjects and 20 subjects with treated chronic periodontitis were recruited. The mid-buccal gingival thickness of upper central and lateral incisors was measured by a customized caliper in all subjects. The crown length and crown width of these teeth were recorded in the healthy group, while gingival recession was measured in the periodontitis group. These outcome measures were compared among the groups and sub-groups, and the correlation of gingival biotypes with clinical parameters was analyzed. RESULTS: The mean thickness of gingiva in the 30 periodontally healthy subjects was 1.05±0.31 mm (0.47-1.57 mm). The males exhibited a greater crown length than the females (P<.05). No significant correlation was found between gingival thickness and the crown width to crown length ratio. The mean gingival thickness at the 80 sites measured in the 20 periodontitis subjects was 0.89±0.29 mm (0.33-1.56 mm). Overall, gingival biotype as measured by gingival thickness was significantly correlated with gingival recession (r=-.240, P=.032), while a stronger correlation was found among the 42 sites with bleeding on probing prior to periodontal treatment (r=-.382, P=.013). CONCLUSION: This study shows that gingival biotype measured by gingival thickness in subjects with treated periodontitis is significantly correlated with gingival recession. Further study could clarify the clinical implications of gingival biotype in the management of periodontal patients.

Impact of ACE2 gene polymorphism on antihypertensive efficacy of ACE inhibitors.

Angiotensin-converting enzyme 2 (ACE2), a newly discovered member of renin-angiotensin-aldosterone system, counterbalances the actions of angiotensin-converting enzyme. The objective of our study was to assess the association between rs2106809 polymorphism in ACE2 gene and the blood pressure response to ACE inhibitors in untreated hypertensive patients. After a 2-week, double-blind placebo run-in period, either benazepril or imidapril was administered for 6 weeks to 497 patients with mild to moderate essential hypertension. The achieved changes in BP were analyzed for their association with genotypes at ACE2 gene loci. In female hypertensive patients, the genotype frequency of ACE2 rs2106809 was 36.7%, 45.2% and 18.1% for CC, CT and TT genotypes, respectively. After 6 weeks of treatment, the reductions in diastolic blood pressure were significantly greater in female patients carrying the CC or CT genotype compared with those carrying the TT genotype (9.62±6.83 or 10.2±7.2 versus 6.81±6.31 mm Hg, respectively; P=0.045, analysis of variance (ANOVA)). Moreover, the reductions in mean arterial pressure were significantly greater in female patients carrying the CC or CT genotype compared with those carrying the TT genotype (12.1±7.5 or 12.0±7.9 versus 8.38±6.83 mm Hg, respectively; P=0.035, ANOVA). In male hypertensive patients, the genotype frequency of ACE2 rs2106809 was 58.1% and 41.9% for C and T genotypes, respectively. However, no association could be observed in males. We conclude that ACE2 rs2106809 is an important predictive factor of the response to antihypertensive treatment with ACE inhibitors in Chinese female hypertensive patients.

Global burden of oral diseases: emerging concepts, management and interplay with systemic health.

OBJECTIVES: This study presents the global burden of major oral diseases with an exegetical commentary on their current profiles, the critical issues in oral healthcare and future perspectives. METHODS: A narrative overview of current literature was undertaken to synthesise the contexts with critical elaboration and commentary. RESULTS: Oral disease is one of the most common public health issues worldwide with significant socio-economic impacts, and yet it is frequently neglected in public health policy. The oral data extracted from the Global Burden of Disease Study in 2010 (Murray et al, 2012) show that caries, periodontal disease, edentulism, oral cancer and cleft lip/palate collectively accounted for 18 814 000 disability-adjusted life-years; and the global burden of periodontal disease, oral cancer and caries increased markedly by an average of 45.6% from 1990 to 2010 in parallel with the major non-communicable diseases like diabetes by 69.0%. Oral diseases and non-communicable diseases are closely interlinked through sharing common risk factors (e.g. excess sugar consumption and tobacco use) and underlying infection/inflammatory pathways. CONCLUSIONS: Oral disease remains a major public health burden worldwide. It is of great importance to integrate oral health into global health agenda via the common risk factor approach. The long-term sustainable strategy for global oral health should focus on health promotion and disease prevention through effective multidisciplinary teamwork.

Immunohistochemistry of lymphocytes in benign lymphoadenosis of oral mucosa.

Benign lymphoadenosis of oral mucosa (BLOM) is a common oral mucosa disease and may be regarded as a precancerous lesion. However, the association between its biological behavior and lymphocyte distribution remains unclear. Therefore, to investigate the characteristics of BLOM, we studied the infiltration of lymphocytes associated with it. The expression levels of CD74, CD20, CD3, and CD45RO were evaluated by immunohistochemical staining in 14 sam-ples from BLOM, 9 samples from BLOM with atypia hyperplasia, 11 samples from BLOM with canceration, and 10 samples from normal oral mucosa tissues. The results were analyzed by two-sample t-test using SPSS 10.0 for Windows, and P < 0.05 was considered to be sig-nificant. In normal oral mucosa, positive expression levels of CD3 and CD45RO were presented in the extra-lymphoid follicle, and the expres-sion levels of CD74 and CD20 were negative. In all BLOM groups, the expression level of CD20 was positive except for one case of BLOM with canceration; the expression levels of CD74 were all positive. Posi-tive expression levels of CD3 and CD45RO could be found not only in extra-lymphoid follicles but also in inner-lymphoid follicles in the BLOM groups. The expression levels of CD74 and CD20 in extra-lym-phoid follicles, and CD3 and CD45RO in inner-lymphoid follicles in BLOM were significantly higher than in BLOM with canceration. The infiltrated lymphocytes in BLOM comprise T- and B-cells. This indi-cates that the lymphoid tissue in BLOM is mucosa-associated lymphoid tissue and BLOM is a proliferative lesion.

Periodontal ligament stem cells: an update and perspectives.

Chronic periodontitis is a serious infectious and inflammatory oral disease of humans worldwide. Conventional treatment modalities are effective for controlling periodontal disease. However, the regeneration of damaged periodontal tissues remains a major challenge in clinical practice due to the complex structure of the periodontium. Stem cell-based regenerative approaches combined with the usage of emerging biomaterials are entering a new era in periodontal regeneration. The present review updates the current knowledge of periodontal ligament stem cell-based approaches for periodontal regeneration, and elaborates on the potentials for clinical application.

The role of lipopolysaccharide-binding protein in innate immunity: a revisit and its relevance to oral/periodontal health.

Lipopolysaccharide (LPS)-binding protein (LBP) functions as an acute phase protein and plays a key role in the innate immune response to bacterial challenge. It is a potential acute-phase biomarker in monitoring the progress of severe sepsis, infectious endocarditis and cardiovascular disease. LBP is mainly synthesized in hepatocytes and generates binding of bacteria and/or their products such as LPS to cell surface receptors, thereby initiating an innate host response. Interestingly, LBP has a dual role depending on its relatively low or high concentrations, and augments or downregulates the innate host defense accordingly. Emerging evidence indicates that LBP can be produced by non-hepatocytes, including respiratory type II epithelial cells, intestinal epithelial cells and human gingival epithelia. These findings suggest that LBP formation at extrahepatic cells may be crucial in containing microbial in situ challenge constantly, critically contributing to tissue homeostasis. This review provides an update on the characteristics and novel functions of LBP as well as its gene polymorphisms and potential use as a biomarker in assessing common infectious and inflammatory diseases such as periodontal disease. This paper highlights the expression profiles of LBP in human oral/gingival cells, how its expression could be modulated by periodontopathogens such as Porphyromonas gingivalis, as well as the relevant regulation mechanisms and signaling pathways involved. The critical roles of LBP in periodontal homeostasis and perspectives for its clinical application are discussed.

Human umbilical vein endothelial cells synergize osteo/odontogenic differentiation of periodontal ligament stem cells in 3D cell sheets.

BACKGROUND AND OBJECTIVE: To investigate the expression of osteo/odontogenic differentiation markers and vascular network formation in a 3D cell sheet with varying cell ratios of periodontal ligament stem cells (PDLSCs) and human umbilical vein endothelial cells (HUVECs). MATERIAL AND METHODS: Human PDLSCs were isolated and characterized by flow cytometry, and co-cultured with HUVECs for the construction of cell sheets. Both types of cells were seeded on temperature-responsive culture dishes with PDLSCs alone, HUVECs alone and various ratios of the latter cells (1 : 1, 2 : 1, 5 : 1 and 1 : 5) to obtain confluent cell sheets. The expressions of osteo/odontogenic pathway markers, including alkaline phosphatase (ALP), bone sialoprotein (BSP) and runt-related transcription factor 2 (RUNX2), were analyzed at 3 and 7 d using RT-PCR. Further ALP protein quantification was performed at 7 and 14 d using ALP assay. The calcium nodule formation was assessed qualitatively and quantitatively by alizarin red assay. Histological evaluations of three cell sheet constructs treated with different combinations (PDLSC-PDLSC-PDLSC/PDLSC-HUVEC-PDLSC/co-culture-co-culture-co-culture) were performed with hematoxylin and eosin and immunofluorescence staining. Statistical analysis was performed using t-test (p < 0.05). RESULTS: Significantly higher ALP gene expression was observed at 3 d in 1 : 1 (PDLSC-HUVEC) (2.52 ± 0.67) and 5 : 1 (4.05 ± 1.07) co-culture groups compared with other groups (p < 0.05); this was consistent with ALP protein quantification. However, the expression of BSP and RUNX2 genes was higher at 7 d compared to 3 d. Significant calcium mineralization was detected as quantified by alizarin red assay at 14 d in 1 : 1 (1323.55 ± 6.54 µm) and 5 : 1 (994.67 ± 4.15 µm) co-cultures as compared with monoculture cell sheets (p < 0.05). Hematoxylin and eosin and CD31 immunostaining clearly exemplified the development of a layered cell sheet structure with endothelial cell islands within the constructed PDLSC-HUVEC-PDLSC and co-culture groups. Furthermore, HUVECs invaded the layered cell sheet, suggestive of rudimentary vascular network initiation. CONCLUSION: This study suggests that the PDLSC-HUVEC co-culture, cell sheet, model exhibits significantly high levels of osteo/odontogenic markers with signs of initial vascular formation. This novel 3D cell sheet-based approach may be potentially beneficial for periodontal regenerative therapy.

Peri-implant conditions and their relationship with periodontal conditions in Chinese patients: a cross-sectional study.

OBJECTIVES: To analyze the relationships between peri-implant conditions and periodontal conditions in Chinese patients with dental implants in place for at least 1 year. MATERIAL AND METHODS: Seventy-six patients (mean age, 41 ± 10 years; range, 21-69 years) who received placement of 120 dental implants (Straumann(®) ), (mean 1.6 implants per subject; range, 1-5 implants per subject) after a mean period of 25 months (range, 12-66 months) responded to recall. Clinical examinations were performed around the implants and natural teeth. Periapical radiographs were taken by the long cone technique for implants, and radiographic bone level (BL) was measured. Comparisons of the peri-implant conditions were performed between the patients with different periodontal conditions by t-test and chi-square test. The relative risk of periodontal condition as a risk factor for peri-implant conditions was analyzed by logistic regression. RESULTS: Subjects who presented with ≥5% sites with probing depth (PD) ≥ 4 mm and ≥30% sites with bleeding on probing (BoP) in the dentition showed significantly poorer peri-implant conditions (58% vs. 18% subjects who had maximum modified gingival index (mGI) 2 or 3, P = 0.003; 94% vs. 62% subjects who had maximum PD ≥ 4 mm, P = 0.008; 100% vs. 79% subjects who had BoP, P = 0.044; mean PD 3.36 ± 0.66 vs. 2.75 ± 0.66 mm, P = 0.002; and sites% with BoP 68 ± 23% vs. 36 ± 31%, P < 0.001), as compared with those who had <5% sites with PD ≥ 4 mm and <30% sites with BoP on the remaining teeth. The relative risk for subjects with the more severe and extensive periodontal conditions compared to those with better periodontal conditions to have PD ≥ 5 mm with BoP at peri-implant sites was 23.3 (P = 0.003, 95% CI, 2.8-192.3. CONCLUSIONS: The peri-implant conditions were significantly related to the periodontal conditions around the remaining natural teeth, which implies that control of periodontal disease is essential for successful implant treatment.

Expression profile of macrophage migration-inhibitory factor in human gingiva and reconstituted human gingival epithelia stimulated by Porphyromonas gingivalis lipopolysaccharide.

BACKGROUND AND OBJECTIVE: Macrophage migration-inhibitory factor (MIF) plays crucial roles in the recruitment and activation of macrophages as well as in helping to kill bacteria. This study investigated the expression profile of MIF in human gingiva under different periodontal conditions and its expression patterns induced by Porphyromonas gingivalis lipopolysaccharide (LPS) in gingival epithelia. MATERIAL AND METHODS: Gingival tissue samples were collected from deep pockets and clinically healthy sites of 22 nonsmoking subjects with chronic periodontitis. The expression of MIF mRNA and protein was evaluated using real-time PCR and immunohistochemistry, respectively. The in vitro study analyzed the effects of P. gingivalis LPS on the expression of MIF in a reconstituted human gingival epithelia (RHGE) model. RESULTS: In gingival epithelia, MIF protein was diffusely expressed from the basal layer to the granular and spinous layers; whereas, in the underlying connective tissues, MIF was observed around the dilated blood vessels in the deep-pocket tissues. A significantly lower level of expression of MIF mRNA and an increased level of expression of MIF protein were found in deep-pocket tissues compared with clinically healthy tissues. Expression of MIF mRNA in the RHGE model was significantly down-regulated by P. gingivalis LPS. CONCLUSION: The present study suggests that MIF expression may be related to periodontal conditions and that its expression profile could be modulated by P. gingivalis LPS. MIF may play a role in periodontal pathogenesis.

Nuclear factor-κB and p38 mitogen-activated protein kinase signaling pathways are critically involved in Porphyromonas gingivalis lipopolysaccharide induction of lipopolysaccharide-binding protein expression in human oral keratinocytes.

Lipopolysaccharide (LPS) -binding protein (LBP) plays a crucial role in innate host response to bacterial challenge. Porphyromonas gingivalis is a keystone pathogen in periodontal disease and the shift of P. gingivalis LPS lipid A structure from penta-acylated (LPS(1690)) to tetra-acylated (LPS(1435/1449)) isoform may significantly contribute to periodontal pathogenesis. We recently demonstrated that LBP is expressed in human gingiva and contributes to periodontal homeostasis. Furthermore, different isoforms of P. gingivalis LPS differently modulate the immuno-inflammatory response, and P. gingivalis LPS(1690) induces LBP expression in human oral keratinocytes (HOKs). This study further examined the signaling mechanisms of P. gingivalis LPS(1690) -induced and Escherichia coli LPS-induced LBP expression in HOKs. Both P. gingivalis LPS(1690) and E. coli LPS were potent inducers of LBP expression in HOKs. The former activated phosphorylation of IκBα, p65, p38 mitogen-activated protein kinase (MAPK) and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), whereas the latter phosphorylated IκBα, p38 MAPK and SAPK/JNK. A nuclear translocation of NF-κB transcription factor was confirmed upon stimulation by both forms of LPS. Further blocking assay showed that P. gingivalis LPS(1690) induction of LBP was through NF-κB and p38 MPAK pathways, whereas E. coli LPS-induced LBP expression was mediated by NF-κB, p38 MPAK and JNK pathways. This study demonstrates that NF-κB and p38 MAPK signaling pathways are involved in P. gingivalis LPS(1690) induction of LBP expression in HOKs. The current findings could enhance the understanding of the molecular mechanisms of innate defense in maintenance of periodontal homeostasis.

Pseudomonas aeruginosa lipopolysaccharide inhibits Candida albicans hyphae formation and alters gene expression during biofilm development.

Elucidation of bacterial and fungal interactions in multispecies biofilms will have major impacts on understanding the pathophysiology of infections. The objectives of this study were to (i) evaluate the effect of Pseudomonas aeruginosa lipopolysaccharide (LPS) on Candida albicans hyphal development and transcriptional regulation, (ii) investigate protein expression during biofilm formation, and (iii) propose likely molecular mechanisms for these interactions. The effect of LPS on C. albicans biofilms was assessed by XTT-reduction and growth curve assays, light microscopy, scanning electron microscopy (SEM), and confocal laser scanning microscopy (CLSM). Changes in candidal hypha-specific genes (HSGs) and transcription factor EFG1 expression were assessed by real-time polymerase chain reaction and two-dimensional gel electrophoresis, respectively. Proteome changes were examined by mass spectrometry. Both metabolic activities and growth rates of LPS-treated C. albicans biofilms were significantly lower (P < 0.05). There were higher proportions of budding yeasts in test biofilms compared with the controls. SEM and CLSM further confirmed these data. Significantly upregulated HSGs (at 48 h) and EFG1 (up to 48 h) were noted in the test biofilms (P < 0.05) but cAMP levels remained unaffected. Proteomic analysis showed suppression of candidal septicolysin-like protein, potential reductase-flavodoxin fragment, serine hydroxymethyltransferase, hypothetical proteins Cao19.10301(ATP7), CaO19.4716(GDH1), CaO19.11135(PGK1), CaO19.9877(HNT1) by P. aeruginosa LPS. Our data imply that bacterial LPS inhibit C. albicans biofilm formation and hyphal development. The P. aeruginosa LPS likely target glycolysis-associated mechanisms during candidal filamentation.

Periodontal therapy decreases serum levels of adipocyte fatty acid-binding protein in systemically healthy subjects: a pilot clinical trial.

BACKGROUND AND OBJECTIVE: Adipocyte fatty acid-binding protein (A-FABP) is expressed in adipocytes, macrophages and microvascular endothelial cells, and it plays a central role in inflammation, atherosclerosis and metabolic responses. This pilot study investigated the effect of nonsurgical periodontal therapy on the serum levels of A-FABP in subjects with chronic periodontitis. MATERIAL AND METHODS: A pilot clinical trial was conducted in 24 otherwise healthy Chinese subjects with moderate to severe chronic periodontitis. The treatment group (n = 12) received nonsurgical periodontal therapy immediately, whereas in the control group (n = 12) the treatment was delayed for 3 months. The serum levels of A-FABP were measured by ELISAs. Other inflammatory and endothelial biomarkers and periodontal conditions were evaluated at baseline and at the 3-month follow-up appointment. RESULTS: A-FABP levels decreased significantly in the treatment group compared with the control group (treatment effect: -1.7 ng/mL; 95% confidence interval: -2.8 to -0.6; p = 0.003). The treatment also significantly improved periodontal conditions but had no significant effect on other biomarkers. In the multivariable regression model, the change in the percentage of sites with detectable plaque was significantly associated with the change in the level of A-FABP (beta: 0.04, 95% confidence interval: 0.01-0.06, p = 0.004). CONCLUSION: Within the limitations of this pilot study, the current findings suggest that treatment of periodontitis may significantly decrease the serum levels of A-FABP. Further longitudinal study with a large sample size is warranted to confirm this finding and elaborate the relevant clinical implications.