Chronic periodontitis induces the proliferation of pancreatic ß-cells to cause hyperinsulinemia in a rat model.

BACKGROUND AND OBJECTIVE: The purpose of this study was to determine if chronic periodontitis (CP) may induce hyperinsulinemia and may have the effect of on pancreatic ß-cell proliferation in a rat model. MATERIALS AND METHODS: Twelve male Sprague-Dawley rats were divided into two groups: the CP group and the control group (Con group). The following contents were evaluated: pathological changes in periodontal soft and hard tissues; serum lipopolysaccharide (LPS) level, serum fasting insulin (FINS) level, fasting blood glucose (FBG) level, and homeostasis model assessment (HOMA) ß (HOMA-ß) index; histopathological examination of islets; immunohistochemistry of insulin and p-Smad2 expression in islets; immunofluorescence of changes in the relative number of ß-cells and the number of Ki67-positive ß-cells. Western blotting was used to analyze p-Smad2/Smad2 levels. Results were analyzed by two independent samples t tests. RESULTS: Increased serum LPS level, FINS level, and HOMA-ß index were observed in the rats of the CP group; FBG level did not change significantly; histological assessments showed an enlarged islet area, increased insulin content, relatively increased ß-cells, increased Ki67-positive ß-cells, and decreased p-Smad2 expression in islets in the rats of the CP group. CONCLUSION: Our study results link CP-induced hyperinsulinemia with changes in islets, such as islet hyperplasia and compensatory ß-cell proliferation, by using a CP rat model.

Periodontitis-induced oral microbiome alterations provide clues on how periodontitis exacerbates colitis.

AIM: To evaluate whether and how microbiota-derived metabolites associated with periodontitis aggravate colitis in mice. MATERIALS AND METHODS: A mouse model of periodontitis and colitis was constructed. Unbiased transcriptomic analyses of the colon were performed to explore important pathways through which periodontitis exacerbated colitis. Oral and gut bacteria were analysed using 16S rRNA sequencing. Gas chromatography-mass spectrometry was used to observe the alterations of oral and gut metabolites. Isolated intestinal lamina propria lymphocytes were analysed by flow cytometry. Inflammasome pathway was detected using qRT-PCR, Western blotting or ELISA. RESULTS: Periodontitis activated the colonic inflammasome pathway and altered the gut microbial composition and metabolite profiles in mice with colitis. Notably, periodontitis induced increase of the faecal metabolite isoleucine (Ile) which was synthesized by microbiota and plants. Moreover, periodontitis upregulated the Ile levels in saliva, but not in serum, indicating that Ile might be an oral pathobiont-synthesizing metabolite that transited from the oral cavity to the gut. Ile triggered the inflammasome pathway, upregulated the number of inflammatory IL-1ßhigh MHCIIhigh Ly6Chigh monocytes in colonic lamina propria, and exacerbated colitis. Further studies found that the Ile metabolite acetyl-coenzyme A positively regulated NLRP3 inflammasome by KAT5-mediated acetylation of NLRP3. CONCLUSIONS: Our study revealed that alteration in periodontitis-induced microbial metabolites deteriorated colitis in a mouse model and that this was associated with Ile production.

Effect of a neodymium-doped yttrium aluminium garnet laser on the physicochemical properties of contaminated titanium surfaces and macrophage polarization.

AIM(S): The objective of this study was to evaluate the changes in the physical and chemical properties of titanium surfaces contaminated by a Nd:YAG laser with different levels of energy and the regulation of macrophage polarization. MATERIALS AND METHODS: The titanium specimens were divided into four groups. The blank control group consisted of the above-mentioned contaminated titanium specimens, and the conditioned control group consisted of sandblasted and acid-etched (SLA) titanium surfaces. The blank control and condition control groups were sealed and preserved in a sterile dark box. There were two experimental groups treated with the Nd:YAG laser-one with 0.5 W and the second with 1.0 W. Surface characteristics were evaluated using scanning electron microscopy, surface profilometry, and contact angle assays. The macrophage viability and proliferation of mouse RAW246.7 were analysed, and the macrophage surface markers, macrophage cytokines, and inflammatory and anti-inflammatory genes were expressed. RESULTS: The Nd:YAG laser increased the hydrophilicity and roughness of the titanium surface after decontamination. Fewer RAW264.7 cells were observed on the titanium surface after Nd:YAG decontamination than on the contaminated titanium surface expressing the M1-type macrophage marker CCR7, whereas more cells were observed after decontamination than on the contaminated titanium surface expressing the M2-type macrophage marker CD206. Following Nd:YAG laser treatment, the secretion of the inflammatory cytokines IL-1ß and TNF-α by RAW264.7 cells on the titanium surface was decreased, whereas the secretion of the anti-inflammatory cytokines IL-4 and IL-10 was increased. RAW264.7 cells cultured for 3 days on the titanium surface after Nd:YAG decontamination treatment expressed significantly reduced levels of the inflammation-related genes IL-1ß, TNF-α, IL-6 and iNOS. The expression of the anti-inflammatory genes Arg-1, IL-4, IL-10 and TGF-ß by RAW264.7 cells was significantly up-regulated after 3 days of incubation on the titanium surface after Nd:YAG decontamination treatment. CONCLUSION(S): The Nd:YAG laser increased the hydrophilicity and roughness of the titanium surface after decontamination, and this change inhibited M1-type macrophage polarization and promoted M2-type macrophage polarization.

Performance of lignin impregnated biochar on tetracycline hydrochloride adsorption: Governing factors and mechanisms.

Corn stalk-based and wheat straw-based biochar were modified by lignin impregnation and applied to adsorb tetracycline hydrochloride (TCH) in wastewater. Porous properties of lignin impregnated biochar were improved and showed better adsorption performance for TCH. Lignin impregnated wheat straw biochar (WS-L) had the maximum adsorption capacity of 31.48 mg/g, which was 1.89 times compared to corresponding pristine biochar, because excellent pore structure developed via the lignin impregnation and carbonization. The adsorption behavior of TCH molecules on biochar could be interpreted well by two-step process, and it postulated to be a physical adsorption process based on pore filling, hydrogen bonding, π-π interaction, and electrostatic interactions. And cations including Na+, K+, Mg2+ and Al3+ could compete with TCH for adsorption, while Ca2+ could promote TCH adsorption by forming tetracycline-Ca2+ complexes. Maximum TCH adsorption occurred at pH of 7. The best performing lignin impregnated biochar was WS-L that demonstrated the biochar modulated by lignin had the potential to remove antibiotics from aqueous solutions.

Comparison of early osseointegration between laser-treated/acid-etched and sandblasted/acid-etched titanium implant surfaces.

This study was designed to compare the early osseointegration of titanium surfaces prepared via laser-treated/acid-etched (LA) and sandblasted/acid-etched (SLA) in dogs. Titanium implants were divided into two groups: Surfaces of the experimental group were treated via LA, while in the control group, surfaces were treated via SLA. The physical and chemical properties of LA and SLA surfaces were tested and compared. Sixteen implants with LA or SLA surfaces were placed into the tibias of four beagle dogs, each treatment group received two implants per single tibia. The dogs were sacrificed two and four weeks after implant placement. Scanning electron microscopy showed that both the LA and SLAs surface exhibited rough structures with micro pores sized 1-3 µm. In the LA surface, regular melting points were observed. However, in the SLA surface, the structure was irregular and few oxide aluminum particles still remained. Only titanium and a small amount of titanium compounds were detected on LA surfaces, while Al was found of SLA surfaces. The LA surface roughness was above that of SLA surfaces (LA: Ra: 2.1 µm; SLA: Ra :1.53 µm; P < 0.01). Both groups exhibited good osseointegration and no significant differences were found in the BIC% at two or four weeks between both groups (P > 0.05). Both groups exhibited good osseointegration; however, the LA surface was cleaner and more uniform than the SLA surface, and no significant differences were found between both groups.

Serum metabolomics provides clues in understanding colitis exacerbating experimental periodontitis in female mice.

OBJECTIVES: To evaluate the pathogenic role of colitis in experimental periodontitis and explore the potential serum metabolites of colitis exacerbating experimental periodontitis in mice model. DESIGN: C57BL/6 mice were divided into four groups (five mice in each group), including control, periodontitis, colitis and colitis+periodontitis group. Mice treated with 1.5 % dextran sulfate sodium for 14 days to induce colitis. On the seventh to fourteenth days, the experimental periodontitis model was established by installing a bacterially retentive ligature between two molars. Histological alteration of periodontium and colon was observed by hematoxylin and eosin staining. Tartrate-resistant acid phosphatase staining and micro-computed tomography was applied to evaluate alveolar bone loss. Gas chromatography-mass spectrometry was used to characterize serum metabolic profiles. RESULTS: Mice in colitis+periodontitis group displayed increased periodontal inflammation and alveolar bone loss when compared with the mice of periodontitis group, suggesting colitis aggravated periodontitis. Metabolomics analysis combined with enrichment analysis showed that colitis significantly (P＜0.05) altered the content of compounds associated with five metabolic pathways (e.g. fatty acid biosynthesis) of periodontitis mice. Notably, colitis significantly reduced the level of serum metabolites that inhibited the formation of osteoclasts (e.g. oleic acid) or anti-inflammatory metabolites (e.g. palmitoleic acid, palmitelaidic acid and chlorogenic acid) of periodontitis mice. CONCLUSIONS: Our findings showed that colitis might aggravate periodontitis and this might be associated with alteration of serum metabolic profiles.

Environmental behaviors and degradation methods of microplastics in different environmental media.

Microplastics, as a group of emerging contaminants, are widely present in environmental media and have the potential to endanger the ecological environment and human health. Due to the inconsistencies and difficulties inherent in the analysis of microplastic particles, global monitoring data on the distribution of microplastics in the environment are still far from sufficient. The fate and migration of microplastics in the environment are also uncertain. Therefore, there have been increasing reviews on the distribution, biological effects, migration, and health risks of microplastics. However, reports focusing on the degradation of microplastics are still rare. Understanding and commanding the environmental behavior of microplastics are of great significance to explore the treatment of microplastic pollution. Although some preliminary studies on microplastics have been carried out, there is still an urgent need to conduct a comprehensive study on environmental behaviors and degradation methods of microplastics in different environmental media. This article summarizes the recent advances on microplastics, basically includes the distribution and ecological impact of microplastics in soil and water environments, then elaborates the migration behavior and influencing factors of microplastics, and focuses on the research progress of microplastics degradation methods. On this basis, the problems existing in the current research and the future development directions have been proposed. This review could provide a more systematic reference for the development and research of microplastics in the future.

Porphyromonas gingivalis lipopolysaccharide (Pg-LPS) influences adipocytes injuries through triggering XBP1 and activating mitochondria-mediated apoptosis.

Obesity is an important public-health problem worldwide. This study aimed to determine effects of porphyromonas gingivalis lipopolysaccharide (Pg-LPS) on adipocytes injuries and explore associated mechanisms. Adipocytes were isolated from SD rats. pLVX-XBP1 (XBP1 over-expression) and pLVX-XBP1-RNAi (silencing XBP1) were structured and transfected into adipocytes. All adipocytes were divided into pLVX-NC, pLVX-XBP1, pLVX-NC+Pg-LPS and pLVX-XBP1+ Pg-LPS group. Oil-Red O staining was employed to identify isolated adipocytes. Quantitative real-time PCR (qRT-PCR) was used to examine gene transcription of IL-6, TNF-α, leptin, adiponectin. Western blotting was used to detect Bax and caspase-3 expression. Adipocytes were successfully isolated and identified with Oil-Red O staining. Both XBP1 mimic and XBP1 RNAi were effectively transfected into adipocytes with higher expressing efficacy. XBP1 over-expression significantly aggravated Pg-LPS induced inflammatory response compared to adipocytes without Pg-LPS treatment (p<0.05). Pg-LPS significantly enhanced leptin and inhibited adiponectin expression by up-regulating XBP1 expression (p<0.05). XBP1 silence significantly alleviated Pg-LPS induced inflammatory response and reduced leptin, enhanced adiponectin expression in Pg-LPS treated adipocytes compared to adipocytes without Pg-LPS treatment (p<0.05). Pg-LPS induced apoptosis of adipocytes by enhancing XBP1 expression and modulating Bcl-2/Bax pathway associated molecules. In conclusion, Porphyromonas gingivalis lipopolysaccharide (Pg-LPS) induces adipocytes injuries through modulating XBP1 expression and initialling mitochondria-mediated apoptosis.

[Analysis of clinical aesthetic effect of buccal alveolar ridge preservation and connective tissue transplantation with single implant].

PURPOSE: To evaluate the clinical aesthetic effect of buccal alveolar ridge preservation (ARP) and connective tissue transplantation (CTG) in patients who received a single implant. METHODS: Forty-three patients with tooth loss admitted to the Department of Stomatology of Shunde Hospital of Southern Medical University from May 2014 to May 2016 were included in the study. Tooth extraction, ARP, implant implantation, CTG and permanent repair were performed respectively. The incidence of bleeding, depth of probing, marginal bone resorption, and red-white aesthetic effect of implants were evaluated 1 year and 3 years after surgery. The buccal mucosa thickness of implants before, immediately after CTG, 1 year and 3 years after surgery were measured. The patient satisfaction was evaluated by visual analogue scale (VAS) from masticatory function, overall aesthetics, attachment height, and color, respectively. The implant conditions at the third year after surgery were observed, and complications during follow-up were recorded. SPSS 20.0 software package was used for statistical analysis of the data. RESULTS: The follow-up rate in the first year after surgery was 100%, and that in the third year after surgery was 90.70%. One year and 3 years after operation, the aesthetic effect of the implant was satisfactory. At the 3rd year after operation, the scores of the near middle gingival papillary were significantly higher than that at the 1st year after operation (P<0.05). The buccal mucosal thickness of the implant immediately after CTG and 1 year and 3 years after surgery increased significantly compared with that before CTG (P<0.05). The buccal mucosal thickness of the implant increased 1.02 mm (relative stability: 90.12%) 1 year after operation and 1.01 mm (relative stability: 84.31%) 3 years after operation, respectively. The satisfaction scores of the patients on chewing function, overall aesthetics, attachment height and color of the implant immediately after CTG, one year after surgery and 3 years after surgery were all > 8. The 3-year survival rate of the implants was 100%, and the 3-year success rate of the implants was 97.44%. During the follow-up, two patients developed peri-implant mucositis, which was relieved after tooth cleaning, but no complications such as tissue flap necrosis, limited opening and tongue movement disorder occurred. CONCLUSIONS: ARP and CTG have good clinical and aesthetic effects on patients with tooth loss. In three years, the buccal mucosal thickness of the implant can be increased and relatively stable, which is worthy of clinical promotion and application.

Recombinant virus-like particle presenting a newly identified coxsackievirus A10 neutralization epitope induces protective immunity in mice.

Coxsackievirus A10 (CVA10) has emerged as one of the major pathogens of hand, foot, and mouth disease in recent years. However, there are no approved vaccines or effective drugs against CVA10. Several experimental CVA10 vaccines have been shown to elicit neutralizing antibodies that could confer protection against viral infection. However, neutralizing antigenic sites on CVA10 capsid have not been well characterized. Here, we report the characterization of linear neutralization epitopes of CVA10 and the development of a CVA10 vaccine based on the identified epitopes. We showed that peptide VP2-P28, corresponding to residues 136 to 150 of VP2, were recognized by anti-inactivated CVA10 sera and effectively inhibited anti-CVA10 sera-mediated neutralization, suggesting that this peptide contains neutralizing epitopes. Insertion of VP2-P28 into hepatitis B core antigen (HBc) resulted in a chimeric virus-like particle (VLP; designated HBc-P28) with the CVA10 epitope exposed on the particle surface. HBc-P28 VLP elicited strong antibody responses against VP2-P28 in mice. Anti-HBc-P28 sera could neutralize both CVA10 clinical isolates and prototype strain, consistent with the fact that the VP2-P28 sequence is highly conserved among CVA10 strains. In addition, anti-HBc-P28 sera failed to cross-neutralize other HFMD-causing enteroviruses, indicating that neutralizing antibodies elicited by HBc-P28 VLP were CVA10-specific. Importantly, anti-HBc-P28 sera were able to provide efficient protection against lethal CVA10 infection in recipient mice. Collectively, these data show that peptide VP2-P28 represents a CVA10-specific linear neutralizing antigenic site and chimeric VLP displaying this peptide is a promising epitope-based CVA10 vaccine candidate.

Coxsackievirus A10 atomic structure facilitating the discovery of a broad-spectrum inhibitor against human enteroviruses.

Coxsackievirus A10 (CV-A10) belongs to the Enterovirus species A and is a causative agent of hand, foot, and mouth disease. Here we present cryo-EM structures of CV-A10 mature virion and native empty particle (NEP) at 2.84 and 3.12 Å, respectively. Our CV-A10 mature virion structure reveals a density corresponding to a lipidic pocket factor of 18 carbon atoms in the hydrophobic pocket formed within viral protein 1. By structure-guided high-throughput drug screening and subsequent verification in cell-based infection-inhibition assays, we identified four compounds that inhibited CV-A10 infection in vitro. These compounds represent a new class of anti-enteroviral drug leads. Notably, one of the compounds, ICA135, also exerted broad-spectrum inhibitory effects on a number of representative viruses from all four species (A-D) of human enteroviruses. Our findings should facilitate the development of broadly effective drugs and vaccines for enterovirus infections.

Coxsackievirus A16 utilizes cell surface heparan sulfate glycosaminoglycans as its attachment receptor.

Coxsackievirus A16 (CVA16) is one of the major pathogens responsible for hand, foot and mouth disease, which affects more than two million children in the Asian-Pacific region annually. Previous studies have shown that scavenger receptor B2 is a functional receptor for CVA16 that facilitates the uncoating process. However, it remains unclear whether other receptors are required for efficient CVA16 infection. In this study, by using a variety of assays we demonstrated that CVA16 utilizes surface heparan sulfate glycosaminoglycans as its attachment receptor. We further showed that five surface-exposed positively charged residues located in a cluster at the five-fold vertex of the virion are critical to heparan sulfate binding and cellular attachment of CVA16. Among the five residues, the arginine at position 166 (R166) of VP1 capsid protein appeared to be the most important for the interaction between CVA16 and heparan sulfate. Alanine substitution at this site (R166A) almost completely abolished heparan sulfate binding and cellular attachment of the virus. Our work achieves insight into the early events of CVA16 infection, thereby providing information that may facilitate the rational design of antiviral drugs and vaccines against CVA16 infection.

[Flocculation characteristics of the return sludge in chemical-biological flocculation process].

The chemical-biological flocculation (CBF) process was used to treat municipal wastewater in Shanghai, and the effect of its return sludge on pollutant removal was studied through stopping chemical addition, simulating different return sludge ratio, and analyzing extracellular polymeric substances (EPS). The results show that the return sludge in CBF exhibits strong pollutant removal capability, and chemical in its return sludge can further TP removal and enhance CBF's adaptability to the influent TP impulse. After stopping PAFC (Al2 O3 : 10.8%, Fe2 O3: 1.8%) addition, COD removal efficiency is achieved at about 50%, and removal rates of PO4(3-) and TP gradually decline. It is also found that chemical addition plays an important role in promote sludge sedimentation in CBF. EPS extracted from CBF is 145.89 mg/g, while EPS from CEPT is only 17.24 mg/g, which indicates that there is strong biological flocculation behavior in CBF. With the increase of return sludge ratio, TP and COD removal efficiencies decrease in CEPT, which reveals that chemical in waste sludge has poor flocculation capability, while CBF return sludge exhibits good flocculation behavior due to its biological flocculation. Chemical flocculation and biological flocculation work collaboratively in CBF process.

[Clinical application of maxillary sinus lift with Summers osteotome].

OBJECTIVE: To introduce and evaluate the procedure and the effect of maxillary sinus lift with closed technique by Summers osteotome, bone grafting and simultaneous implant placement. METHODS: 66 cases with severely resorbed alveolar bone in maxillary posterior region received sinus lift with Summers osteotome, simultaneously bone grafting and implants placement. The final restoration was finished at 6 months postoperatively. RESULTS: The operation procedure were eventless in the 66 cases, the sinus floor were elevated by 2-5 mm, three-dimensional reconstruction of the CT scan pictures showed the smooth dome profile of the lifting sites and no signs of laceration on the membrane, and there were no maxillary antritis after operation. After 6 months, no significantly bone graft resorption and good osseointegration were noticed in X-ray imaging. The final restoration was finished at this time. 12-24 months after the restoration, all implants inserted were remain, the hard and soft tissue were healthy, prosthesis were stable and functioned. X-ray showed good osseointegration in the lifting sites, the vertical resorption around the implants were less than 1 mm. CONCLUSION: With properly use of Summers osteotome, scraps of the bone in the implant sockets can be pushed into the sinus, these autogenous bone scraps were in favor of the osseogenesis and the sinus floor can be easily elevated by the method with very infrequent complications. It enlarged indication of dental implants and avoided operation of harvesting autogenous bone in other site. The method is simple and valuable to clinical application.