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.

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 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.

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.

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.

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.

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.

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.

[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.

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.

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.

Microbial chemical signaling: a current perspective.

Communication among microorganisms is mediated through quorum sensing. The latter is defined as cell-density linked, coordinated gene expression in microbial populations as a response to threshold signal concentrations followed by induction of a synchronized population response. This phenomenon is used by a variety of microbes to optimize their survival in a constantly challenging, dynamic milieu, by correlating individual cellular functions to community-based requirements. The synthesis, secretion, and perception of quorum-sensing molecules and their target response play a pivotal role in quorum sensing and are tightly controlled by complex, multilayered and interconnected signal transduction pathways that regulate diverse cellular functions. Quorum sensing exemplifies interactive social behavior innate to the microbial world that controls features such as, virulence, biofilm maturation, antibiotic resistance, swarming motility, and conjugal plasmid transfer. Over the past two decades, studies have been performed to rationalize bacterial cell-to-cell communication mediated by structurally and functionally diverse small molecules. This review describes the theoretical aspects of cellular and quorum-sensing mechanisms that affect microbial physiology and pathobiology.

Effectiveness of egg yolk immunoglobulin (IgY) against periodontal disease-causing Fusobacterium nucleatum.

AIMS: To evaluate the in vitro and in vivo effectiveness of egg yolk immunoglobulin (IgY) against periodontal disease-causing Fusobacterium nucleatum. METHODS AND RESULTS: Four White Leghorn hens (120 days old) were immunized with whole Fus. nucleatum cells killed with 1% formaldehyde using three injections provided at 2-week intervals. IgY was produced from egg yolks obtained from these immunized hens using water dilution, two-step salt precipitation and ultrafiltration. This IgY was shown to have a purity of 86·8% based on its optical intensity in the stained SDS-PAGE bands. An enzyme-linked immunosorbent assay indicated a high specificity for the IgY against Fus. nucleatum with a maximum antibody titre of 80 000. The IgY had only weak cross-reactivity with Porphyromonas gingivalis, Prevotella intermedia and Solobacterium moorei. Growth and biofilm formation by Fus. nucleatum were inhibited by IgY at concentrations of 10 and 20 mg ml(-1) . Immunofluorescence and immunoelectron microscope assays revealed a high binding ability of specific IgY, which may explain the in vitro effectiveness of IgY. In an in vivo study, IgY treatment resulted in a marked decrease in alveolar bone loss after Fus. nucleatum infection in a mouse model confirming the effectiveness of IgY against periodontal disease-causing Fus. nucleatum. CONCLUSIONS: IgY effectively inhibited growth and biofilm formation by Fus. nucleatum and prevented the progression of periodontal disease by decreasing alveolar bone loss. SIGNIFICANCE AND IMPACT OF THE STUDY: Specific IgY may have potential for the treatment of periodontal disease.

Efficacy of specific IgY for treatment of lipopolysaccharide-induced endotoxemia using a mouse model.

AIMS: To estimate the efficacy of specific egg yolk immunoglobulin (IgY) for the treatment of lipopolysaccharide (LPS)-induced endotoxemia using a mouse model. METHODS AND RESULTS: Specific IgY was obtained from the yolk of hens immunized with formaldehyde-killed Escherichia coli O111 and showed a high binding activity to LPS when subjected to an ELISA. Endotoxemia was induced in mice by intraperitoneal injection of LPS at a dose of 20 mg kg(-1) for measuring survival rate and 10 mg kg(-1) for cytokine measurement. The survival rate of mice treated with 200 mg kg(-1) specific IgY or 5 mg kg(-1) dexamethasone was 70% while none of the mice in the normal saline-treated group survived more than 7 days. Specific IgY significantly (P < 0.05) decreased tumour necrosis factor-α (TNF-α) level and increased interleukin-10 (IL-10) level in the serum of endotoxemia mice. Specific IgY had less of an effect on TNF-α than dexamethasone, while its effect on increasing IL-10 was stronger than dexamethasone. Haematoxylin and eosin-stained sections indicated that IgY attenuated the damage to the lung and liver observed in mice with endotoxemia. CONCLUSIONS: The specific IgY increased the survival rate of mice with endotoxemia induced by LPS, down-regulated TNF-α and up-regulated IL-10 in serum and attenuated the extent of damage to the lung and liver. SIGNIFICANCE AND IMPACT OF THE STUDY: The specific IgY has potential for the treatment of LPS-induced endotoxemia.

Global oral health inequalities: task group--periodontal disease.

Periodontal diseases constitute one of the major global oral health burdens, and periodontitis remains a major cause of tooth loss in adults worldwide. The World Health Organization recently reported that severe periodontitis exists in 5-20% of adult populations, and most children and adolescents exhibit signs of gingivitis. Likely reasons to account for these prevalent diseases include genetic, epigenetic, and environmental risk factors, as well as individual and socio-economic determinants. Currently, there are fundamental gaps in knowledge of such fundamental issues as the mechanisms of initiation and progression of periodontal diseases, which are undefined; inability to identify high-risk forms of gingivitis that progress to periodontitis; lack of evidence on how to prevent the diseases effectively; inability to detect disease activity and predict treatment efficacy; and limited information on the effects of integration of periodontal health as a part of the health care program designed to promote general health and prevent chronic diseases. In the present report, 12 basic, translational, and applied research areas have been proposed to address the issue of global periodontal health inequality. We believe that the oral health burden caused by periodontal diseases could be relieved significantly in the near future through an effective global collaboration.

Microbiology of odontogenic bacteremia: beyond endocarditis.

SUMMARY: The human gingival niche is a unique microbial habitat. In this habitat, biofilm organisms exist in harmony, attached to either enamel or cemental surfaces of the tooth as well as to the crevicular epithelium, subjacent to a rich vascular plexus underneath. Due to this extraordinary anatomical juxtaposition, plaque biofilm bacteria have a ready portal of ingress into the systemic circulation in both health and disease. Yet the frequency, magnitude, and etiology of bacteremias due to oral origin and the consequent end organ infections are not clear and have not recently been evaluated. In this comprehensive review, we address the available literature on triggering events, incidence, and diversity of odontogenic bacteremias. The nature of the infective agents and end organ infections (other than endocarditis) is also described, with an emphasis on the challenge of establishing the link between odontogenic infections and related systemic, focal infections.