[Objective] To resolve the ambiguities of HLA genotyping generated by next generation sequencing (NGS) using nanopore sequencing technology. [Methods] A total of 38 samples with ambiguous HLA genotyping by NGS in our laboratory were collected, and HLA-A, -B, -C, -DRB1, -DRB3/4/5, -DQA1, -DQB1, -DPA1 and -DPB1 loci in these samples were amplified using primers in the same commercial NGS HLA genotyping kit, then subjected to third-generation library construction, and sequenced on the nanopore sequencer. The sequencing data were converted into Fastq files and analyzed by software, and the genotypes of 11 HLA loci were obtained. The ambiguities were counted directly. [Results] The high-resolution genotyping at the second domain of 11 HLA loci of 38 samples using the third generation sequencing (TGS) were consistent with the results of the NGS method at a rate of 100%. The genotypes for the HLA-A, -B, -C, -DRB3, -DRB4, -DQA1 and -DPA1 loci by TGS were all only one result, and the discrimination rate for ambiguities of the HLA-A, -B, -C, and -DQA1 loci (all caused by the difficulty in phasing due to the short NGS read length) was 100%. Among the HLA-DRB1, -DRB5, -DQB1 and -DPB1 loci, the discrimination rate of TGS for the ambiguities caused by non-amplification of exon 1 was 0% and by the short NGS read length was 100%. [Conclusion] Nanopore technology was used to identify the ambiguities of 11 HLA loci in this study, and the ambiguities caused by the short read length disadvantage of the NGS method could be solved effectively and the accuracy of HLA genotyping would be improved.

Objective:To investigate the effects of macrophage(Mφ)polarization on the cementogenic differentiation of human perio-dontal ligament stem cells(hPDLSCs)and the underlying mechanism.Methods:Human monocytic THP-1 cells were induced to M0,M1 and M2 Mφ subsets,then RPM1 1640 medium or supernatants of different Mφ phenotypes were mixed with an equal volume of ce-mentoblastic induction medium to generate conditioned mediums(CMs),and termed as CM-Control,CM-M0,CM-M1 and CM-M2,respectively.hPDLSCs were cultured with different CMs,and the hPDLSCs sheets were then wrapped around treated dentin matrix(TDM)to generate cell sheet/dentin complexes.The complexes were subcutaneously implanted into nude mice.The cementum-like tissue formation was evaluated by HE staining,immunofluorescent staining(IMF)and qRT-PCR were used to detect the expression level of cementogenic differentiation-related markers bone sialoprotein(BSP),cementum attachment protein(CAP)and cementum pro-tein-1(CEMP-1),oxidant-antioxidant system-related markers superoxide dismutase 1(SOD1)and nuclear factor erythroid 2-related factor 2(NRF2),mitophagy-related markers PTEN induced putative kinase 1(PINK1)and microtubule asso ciated proteins 1A/1B light chain 3(LC3).Results:In vivo,CM-M2-treated hPDLSCs(CM-M2)group formed more cementum-like tissues and expressed higher protein levels of CAP,CEMP-1,SOD1,PINK1 and LC3 than that in other groups.In vitro tests showed that,compared with CM-Control group,hPDLSCs incubated with CM-M2 increased the levels of BSP(P＜0.01),CAP(P＜0.001),CEMP-1(P＜0.01)and SOD1(P＜0.05),while no statistically significant difference was detected for NRF2(P＞0.05),and increasedthe expression of PINK1(P＜0.05).Conclusion:M2 Mφ regulate the cementogenic differentiation of hPDLSCs possibly via modulating oxidant-antioxidant system and mitophagy.

Objective:To prepare PLGA electrospinning membranes doped with hollow mesoporous silica nanoparticles loaded with metformin and investigate their biological properties.Methods:PLGA(Control group)and PLGA/HMSN/Met electrospun membranes(Experimental group)were prepared by electrospinning technology.The microscopic morphology of the 2 groups of electrospun mem-branes was observed by SEM.The hydrophilicity,elemental composition and in vitro drug release were detected by contact angle meas-urement,EDS,and drug release test,respectively.SEM and laser scanning confocal microscope(LSCM)were used to observe the growth of periodontal ligament stem cells(PDLSCs)on the 2 groups of electrospun membranes,and CCK-8 assay was used to detect the cell proliferation.Results:Both electrospun membranes had extracellular matrix(ECM)-like fiber structures.The PLGA/HMSN/Met electrospun membranes could slowly release Met for up to 35 days,and the hydrophilicity of PLGA membranes was improved by HMSN-Met doped.The composite electrospun membranes had good cell biocompatibility in vitro,and could promote cell proliferation.Conclu-sion:Modification of PLGA with HMSN-Met can improve the hydrophilicity of PLGA electrospun membranes,continuously release Met,and have good cell biocompatibility.

Objective:To investigate the effects of Porphyromonas gingivalis derived outer membrane vesicles (Pg OMV) on osteoclast differentiation of macrophages and its underlying mechanisms. Methods:The morphology and the size distribution of Pg OMV were analyzed by transmission electron microscopy and nanoparticle tracing analysis, respectively. The osteoclast precursors were treated with 1, 3 and 10 mg/L Pg OMV (1, 3 and 10 mg/L OMV treatment group) or phosphate buffer solution (PBS)(control group). The formation of osteoclasts was analyzed by tartrate-resistant acid phosphase (TRAP) staining and F-actin staining and real-time quantitative PCR (RT-qPCR) were used to detect the expression of Fos and matrix metallopeptidase 9 (MMP9). Polymyxin B (PMB) was used to block lipopolysaccharide (LPS) and then Pg OMV was used to treat osteoclast precursor (PMB-OMV treatment group), and OMV treatment group was used as control. TRAP and F-actin staining were used to observe the formation of osteoclasts and actin rings. The effect of Pg OMV on the expression of Toll-like receptor (TLR) 2 and TLR4 in preosteoclasts was detected by Western blotting. The osteoclast precursors were pretreated with 10, 50, 100 and 200 μmol/L C29, an inhibitor of TLR2, and then treated with Pg OMV(OMV+10, 50, 100 and 200 μmol/L C29 treatment group) and OMV treatment group without C29 pretreatment was control. TRAP and F-actin staining were used to observe the formation of osteoclasts and actin rings. The osteoclast precursor cells were treated with OMV (OMV treatment group) and OMV incubated with PMB (PMB-OMV treatment group) and the expression of TLR2 in osteoclast precursor was detected by Western blotting.Results:Pg OMV showed classical vesicular structures, and the average particle size of Pg OMV were 179.2 nm. A large number of actin rings were observed in the 3 and 10 mg/L OMV treatment groups. The percentages of TRAP-positive osteoclast area in 3 mg/L OMV treatment group [(22.6±2.1)%] and 10 mg/L OMV treatment group [(32.0±2.3)%] were significantly increased compared with control group [(4.9±0.5)%] ( P<0.001). Compared with the control group (1.000±0.029), the mRNA relative expression of Fos in 3 mg/L OMV treatment group (1.491±0.114) and 10 mg/L OMV treatment group (1.726±0.254) was significantly increased ( P=0.013, P=0.001). Compared with the control group (1.007±0.148), the mRNA relative expression of MMP9 in the group of 10 mg/L OMV (2.232±0.097) was significantly increased ( P<0.001). Actin ring formation was less in PMB-OMV treatment groups than in OMV treatment groups. The proportion of TRAP-positive osteoclasts area [(14.8±3.8)%] in PMB-OMV treatment group was significantly lower than OMV treatment group [(31.5±6.7) %] ( P=0.004). The relative expression of TLR2 in OMV treatment group (1.359±0.134) was significantly higher than that in the control group (1.000±0.000) ( t=4.62, P=0.044). Compared with the OMV treatment group [(29.4±1.7)%], 50, 100 and 200 μmol/L C29 significantly decreased the formation of osteoclasts [(24.0±1.7)%, (18.5±2.1)%, (9.1±1.3) %] ( P=0.026, P<0.001, P<0.001). TLR2 protein expression in PMB-OMV group (0.780±0.046) was significantly lower than that in OMV group (1.000±0.000)( t=8.32, P=0.001). Conclusions:Pg OMV can promote osteoclast differentiation by carrying LPS, TLR2 plays an important role in Pg OMV mediated osteoclast differentiation.

Chronic and progressive destruction/damage of the periodontal tissues resulted from periodontitis is the leading cause of tooth loss in adults. Traditional periodontal therapies such as scaling and root planning or flap surgery have demonstrated effective in controlling local inflammation and in suppressing/arresting the disease progression of periodontitis. However, those infection control measures cannot help to regenerate lost periodontal tissues to a statistically or clinically significant degree. Although some successes regarding the reduction of the intrabony defect and maintenance of the periodontal homeostasis have been achieved in periodontal regenerative procedures, comprising but not limited to guided tissue regeneration (GTR) or bone grafting technique, the restorative effectiveness of the architecture and function of the lost or injured tissues is far from our clinical expectation. The use of the concept, technique, and method of tissue engineering for periodontal regeneration is a hotspot and animal studies have shown interesting outcomes in terms of functional regeneration of lost/damaged support tissues in the periodontium, including alveolar bone, periodontal ligament, and cementum. However, numerous issues need to be addressed before those regenerative approaches can be responsibly transformed to novel clinical therapies. Recently, paradigm that induces homing of host stem cells to site of the periodontium and encourage the body's innate capability to repair is a new research field termed endogenous regeneration. Given that endogenous regenerative technique avoids ex- vivo cell culture and transplantation, it should be relatively easier to be used in the treatment of clinical patients. Due to the limited oral microenvironment and harsh periodontal local condition for tissue regeneration, as well as poor understanding of periodontal regenerative biology, there is still a long way ahead to explore new effective, practical, and economical therapies to save and protect natural tooth and for combating highly prevalent periodontal disease.

Objective:To investigate the characteristics of extracellular matrix vesicle mimetics prepared by mechanical extrusion and their effects on the cell viability and osteogenic differentiation potential of human periodontal ligament stem cells (PDLSC).Methods:PDLSC derived extracellular matrix vesicles were prepared by collagenase digestion, while the cell derived vesicle mimetics were simulated by mechanical extrusion. The obtained extracellular matrix vesicles and parental cell derived vesicle mimetics were divided into 4 groups: matrix vesicles derived from PDLSC cultured in basic medium for 7 days (PDLSC matrix vesicles, MVs), vesicle mimetics derived from PDLSC cultured in basic medium for 7 days (PDLSC vesicle mimetics, CVMs), matrix vesicles derived from PDLSC cultured in osteogenic inducing medium for 7 days (osteogenic-induced PDLSC matrix vesicles, O-MVs) and vesicle mimetics derived from PDLSC cultured in osteogenic inducing medium for 7 days (osteogenic-induced PDLSC vesicle mimetics, O-CVMs). Vesicles morphologies and sizes were observed by transmission electron microscopy and nanoparticle tracking analysis. Vesicles uptake was detected by immunofluorescence. With PDLSC as the control group, the effects of vesicles on the viability of PDLSC were detected by cell activity assay (cell counting kit-8), and the effects of vesicles on the osteogenic differentiation potential of PDLSC were detected by alizarin red staining and Western blotting.Results:Vesicles in MVs, O-MVs, CVMs and O-CVMs were all observed with a round structure (size 50-250 nm), and could be taken up by PDLSC without affecting the cell viability. Under osteogenic inducing conditions, PDLSC incubated with O-MVs or O-CVMs could produce more mineralized nodules than those in the control group (PDLSC). MVs, O-MVs, CVMs and O-CVMs could promote the expression of osteogenic-related proteins in PDLSC. PDLSC in group O-CVMs showed significant higher expressions of osteogenic-related proteins, including alkaline phosphatase (ALP) (1.571±0.348), osteopontin (OPN) (1.827±0.627) and osteocalcin (OCN) (1.798±0.537) compared to MVs (ALP: 1.156±0.170, OPN: 1.260±0.293, OCN: 1.286±0.302) ( P<0.05). Compared to CMVs-incubated PDLSC, O-CVMs-incubated PDLSC expressed more Runt-related transcription factor 2 (1.632±0.455 vs 1.176±0.128) and OPN (1.827±0.627 vs 1.428±0.427) ( P<0.05). Moreover, there was no significant difference in the expression levels of osteoblast-related proteins in PDLSC cultured with MVs, O-MVs and CVMs ( P>0.05). Conclusions:The vesicle mimetics prepared by mechanical extrusion method are similar in shape and size to the extracellular matrix vesicles. MVs, O-MVs, CVMs and O-CVMs do not affect the cell viability of PDLSC, and can promote the osteogenic differentiation potential of PDLSC to a certain extent.

The oral cavity is the second largest reservoir of microorganisms in the human body, containing more than 700 species. Periodontal microorganisms are an important part of oral microorganisms. Plaque biofilm, the initiator of periodontal disease, contains an abundance of oral microorganisms. The special complex anatomy of the periodontium allows for a higher abundance of the periodontal microbiota. There are growing evidences show that the periodontal microbiota is not only closely associated with oral diseases, but also plays an important role in mouth-brain interactions. Dysbiosis of the periodontal microbiota may facilitate the progression of neurodegenerative diseases including Alzheimer disease, Parkinson disease, and multiple sclerosis. Here, this paper reviews the bidirectional role of periodontal microbiota between the oral cavity and the brain, that is, the bridge effect of periodontal microbiota involved in the interaction between the two diseases, enumerates the epidemiological and biological evidences that dysregulation of the periodontal microbiota induces and exacerbates neurodegenerative diseases, and analyzes their possible mechanisms. The positive implications of periodontal microbial homeostasis in the prevention and treatment of neurodegenerative diseases are described with the aim of providing new ideas and insights into the pathogenesis and therapeutic approaches for neurodegenerative diseases.

Odontogenic maxillary sinusitis(OMS)is a subtype of maxillary sinusitis(MS).It is actually inflammation of the maxillary sinus that secondary to adjacent infectious maxillary dental lesion.Due to the lack of unique clinical features,OMS is difficult to distinguish from other types of rhinosinusitis.Besides,the characteristic infectious pathogeny of OMS makes it is resistant to conventional therapies of rhinosinusitis.Its current diagnosis and treatment are thus facing great difficulties.The multi-disciplinary cooperation between otolaryngologists and dentists is absolutely urgent to settle these questions and to acquire standardized diagnostic and treatment regimen for OMS.However,this disease has actually received little attention and has been underrepresented by relatively low publication volume and quality.Based on systematically reviewed literature and practical experiences of expert members,our consensus focuses on characteristics,symptoms,classification and diagnosis of OMS,and further put forward multi-disciplinary treatment decisions for OMS,as well as the common treatment complications and relative managements.This consensus aims to increase attention to OMS,and optimize the clinical diagnosis and decision-making of OMS,which finally provides evidence-based options for OMS clinical management.

Endo-periodontal lesions(EPLs)involve both the periodontium and pulp tissue and have complicated etiologies and pathogenic mechanisms,including unique anatomical and microbiological characteristics and multiple contributing factors.This etiological complexity leads to difficulties in determining patient prognosis,posing great challenges in clinical practice.Furthermore,EPL-affected teeth require multidisciplinary therapy,including periodontal therapy,endodontic therapy and others,but there is still much debate about the appropriate timing of periodontal therapy and root canal therapy.By compiling the most recent findings on the etiology,pathogenesis,clinical characteristics,diagnosis,therapy,and prognosis of EPL-affected teeth,this consensus sought to support clinicians in making the best possible treatment decisions based on both biological and clinical evidence.

Periodontitis is a critical risk factor for the occurrence and development of diabetes.Porphyromonas gingivalis may participate in insulin resistance(IR)caused by periodontal inflammation,but the functional role and specific mechanisms of P.gingivalis in IR remain unclear.In the present study,clinical samples were analysed to determine the statistical correlation between P.gingivalis and IR occurrence.Through culturing of hepatocytes,myocytes,and adipocytes,and feeding mice P.gingivalis orally,the functional correlation between P.gingivalis and IR occurrence was further studied both in vitro and in vivo.Clinical data suggested that the amount of P.gingivalis isolated was correlated with the Homeostatic Model Assessment for IR score.In vitro studies suggested that coculture with P.gingivalis decreased glucose uptake and insulin receptor(INSR)protein expression in hepatocytes,myocytes,and adipocytes.Mice fed P.gingivalis tended to undergo IR.P.gingivalis was detectable in the liver,skeletal muscle,and adipose tissue of experimental mice.The distribution sites of gingipain coincided with the downregulation of INSR.Gingipain proteolysed the functional insulin-binding region of INSR.Coculture with P.gingivalis significantly decreased the INSR-insulin binding ability.Knocking out gingipain from P.gingivalis alleviated the negative effects of P.gingivalis on IR in vivo.Taken together,these findings indicate that distantly migrated P.gingivalis may directly proteolytically degrade INSR through gingipain,thereby leading to IR.The results provide a new strategy for preventing diabetes by targeting periodontal pathogens and provide new ideas for exploring novel mechanisms by which periodontal inflammation affects the systemic metabolic state.