MSCs-derived apoptotic extracellular vesicles promote muscle regeneration by inducing Pannexin 1 channel-dependent creatine release by myoblasts / 国际口腔科学杂志·英文版

Severe muscle injury is hard to heal and always results in a poor prognosis. Recent studies found that extracellular vesicle-based therapy has promising prospects for regeneration medicine, however, whether extracellular vesicles have therapeutic effects on severe muscle injury is still unknown. Herein, we extracted apoptotic extracellular vesicles derived from mesenchymal stem cells (MSCs-ApoEVs) to treat cardiotoxin induced tibialis anterior (TA) injury and found that MSCs-ApoEVs promoted muscles regeneration and increased the proportion of multinucleated cells. Besides that, we also found that apoptosis was synchronized during myoblasts fusion and MSCs-ApoEVs promoted the apoptosis ratio as well as the fusion index of myoblasts. Furthermore, we revealed that MSCs-ApoEVs increased the relative level of creatine during myoblasts fusion, which was released via activated Pannexin 1 channel. Moreover, we also found that activated Pannexin 1 channel was highly expressed on the membrane of myoblasts-derived ApoEVs (Myo-ApoEVs) instead of apoptotic myoblasts, and creatine was the pivotal metabolite involved in myoblasts fusion. Collectively, our findings firstly revealed that MSCs-ApoEVs can promote muscle regeneration and elucidated that the new function of ApoEVs as passing inter-cell messages through releasing metabolites from activated Pannexin 1 channel, which will provide new evidence for extracellular vesicles-based therapy as well as improving the understanding of new functions of extracellular vesicles.

A pilot study on the consistency of biological widths measured by periodontal probe and cone-beam CT / 中华口腔医学杂志

Objective@#To compare the consistency of the biological widths measured by using cone-beam CT (CBCT) and periodontal probe in patients with two different gingival biotypes.@*Methods@#Totally 27 patients [13 males, 14 females, (37.6±13.7) years old], who planned to receive the crown lengthening surgery, were recruited under the inclusion and exclusion criteria in Department of Periodontology, School of Stomatology, The Fourth Military Medical University during November 2017 to June 2018. A total of 40 teeth (14 front teeth, 26 posterior teeth) were involved in this study. The patients were divided into two groups according to their gingival biotypes: thin gingival biotype [5 males, 8 females, (40.2±15.0) years old, 21 teeth] and thick gingival biotype [8 males, 6 females, (35.1±11.9) years old, 19 teeth]. All the teeth were checked before crown lengthening procedures by using CBCT, and the biological widths and sulcus depths were measured during the surgery by using periodontal probes (Hu-Friedy, U S A). The data were recorded and statistically analyzed.@*Results@#There were no significant differences of the biological widths between the two measuring methods amongst all of the 40 teeth [periodonial probe: (1.64±0.26) mm; CBCT: (1.69±0.20) mm], amongst 21 thin gingival biotype teeth [periodontal probe: (1.49±0.19) mm; CBCT: (1.57±0.12) mm] and amongst 19 thick gingival biotype teeth [periodontal probe: (1.80±0.21) mm; CBCT: (1.87±0.18) mm] (P>0.05). There were no significant differences of the biological widths [anterior teeth: (1.59±0.15) mm, posterior teeth: (1.67±0.29) mm, P=0.42] and of the sulcus depths [anterior teeth: (2.00±0.28) mm, posterior teeth: (2.11±0.43) mm, P=0.44] between anterior teeth and posterior teeth. The difference of biological widths, measured by two methods respectively, between thin and thick gingival biotype groups was statistically significant (P<0.01). There were significant differences of the sulcus depths, measured by the periodontal probes, between the thin [(1.93±0.28) mm] and thick [(2.24±0.41) mm] gingival biotype groups (P<0.01).@*Conclusions@#The biological widths measured by CBCT is consistent with those measured by using periodontal probes. The biological widths and the depths of the sulcus of thin and thick gingival biotypes are different.

Effects of cell-to-cell communication and histone acetyltransferase on the change of osteogenic differentiation ability among single-cell clones from healthy periodontium with heterogeneity of osteogenic differentiation abilities / 中华口腔医学杂志

Objective@#To investigate the effect of cell-to-cell communication amongst single-cell clones from healthy periodontium with different osteogenic differentiation potentials on change of osteogenic differentiation capabilities and the role histone acetyltransferase partaken in this process.@*Methods@#In order to research the change of osteogenic differentiation ability via cell-to-cell communication, indirect co-culture method was used by placing two single-cell clones with different osteogenesis potentials in each of the 6-well plates. Blank control, weak and strong osteogenic groups were set up, corresponding to Transwell chambers with blank, cells of weak osteogenesis ability and cells of strong osteogenesis ability, respectively. Each group was made in triplicate. After co-culture for four days, Transwell chamber was removed. Quantitative real-time PCR (qPCR) and alizarin red staining were employed to detect the change of osteogenic differentiation ability. The acetylation level of H3 was measured by using Western blotting. Histone acetyltransferases were detected by qPCR.@*Results@#Single-cell clones were ensured from mesenchymal stem cells by flow cytometer, the positive expression of CD29, CD90, CD105, CD146 was (99.80±0.02)%, (99.36±0.18)%, (99.41±0.05)% and (95.10±2.11)%, respectively. And CD31 and CD34 expression were (0.29±0.11)% and (0.22±0.13)%, respectively. Alizarin red and oil red O staining confirmed that single-cell clones had the abilities of adipogenesis and osteogenesis. Alkaline phosphatase (ALP) and alizarin red staining indicated that different single-cell clones were heterogeneity in osteogenesis differentiation. Indirect co-culture indicated that the mRNA expression of osteocalcin (OCN) were 14.24±5.60 and 4.78±2.90, respectively and Runt-related transcription factor 2 (RUNX2) were 2.75±1.44 and 1.61±0.44, respectively, in strong and weak osteogenic groups. They were significantly higher compared to the blank group (the mRNA expression of OCN and RUNX2 were 1.00±0.47 and 1.00±0.39, respectively). The expression of OCN and RUNX2 were also higher in strong osteogenic group than that in weak osteogenic group (P<0.05). The mean gray level of the acetylation of H3 in strong osteogenic group (0.76±0.09) and weak osteogenic group (0.54±0.12) were also higher than that in the blank group (0.30±0.04)(P<0.05). qPCR results showed that KAT6A in strong osteogenic group exhibiting higher expression (P<0.05) compared to weak osteogenic group and the blank group, which were corresponding to the changes of acetylation levels.@*Conclusions@#Single-cell clones from healthy periodontium showed heterogeneity in osteogenic differentiation abilities. Single-cell clones with strong osteogenesis abilities had an advantage over others by promoting others' osteogenesis differentiation and this change mediated by cell-to-cell communication might be caused by modulating KAT6A to affect the acetylation level of histone.

Collaboration from periodontics in the aesthetic restoration of anterior teeth / 华西口腔医学杂志

Anterior teeth are the main zones that reflect oral aesthetics. The histological structure, outside appearance, relative ratios, and other characteristics of tissues must be understood to obtain relatively ideal and natural restoration effects. A collaboration of different disciplines must be implemented to obtain harmonious and stable restoration outcomes that help the majority appreciate beauty. This article aims to discuss the role of periodontics in this collaboration and introduce several common techniques.

Extracellular signal-regulated kinase signaling pathway regulates the endothelial differentiation of periodontal ligament stem cells / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of extracellular signal-regulated kinase (ERK) signaling pathway on the endothelial differentiation of periodontal ligament stem cells (PDLSC).</p><p><b>METHODS</b>Human PDLSC was cultured in the medium with vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (b-FGF) to induce endothelial differentiation. Endothelial inducing cells was incubated with U0126, a specific p-ERK1/2 inhibitor. PDLSC from one person were randomly divided into four groups: control group, endothelial induced group, endothelial induced+DMSO group and endothelial induced+U0126 group. The protein expression of the p-EKR1/2 was analyzed by Western blotting at 0, 1, 3, 6 and 12 hours during endonthelial induction. The mRNA expressions of CD31, VE-cadherin, and VEGF were detected by quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR) after a 7-day induction. The proportion of CD31(+) to VE-cadherin(+) cells was identified by flow cytometry, and the ability of capillary-like tubes formation was detected by Matrigel assay after a 14-day induction. The measurement data were statistically analyzed.</p><p><b>RESULTS</b>Phosphorylated ERK1/2 protein level in PDLSC was increased to 1.24±0.12 and 1.03±0.24 at 1 h and 3 h respectively, during the endothelial induction (P<0.01). The mRNA expressions of CD31 and VEGF in induced+U0126 group were decreased to 0.09±0.18 and 0.49±0.17, which were both significantly different with those in induced group (P<0.05). The proportion of CD31(+) to VE-cadherin(+) cells of induced+U0126 group were decreased to 5.22±0.85 and 3.56±0.87, which were both significantly different with those in induced group (P<0.05). In Matrigel assay, the branching points, tube number and tube length were decreased to 7.0±2.7, 33.5±6.4, and (15 951.0±758.1) pixels, which were all significantly different with those in induced group (P<0.05).</p><p><b>CONCLUSIONS</b>The endothelial differentiation of PDLSC is positively regulated by ERK signaling pathway. Inhibition of ERK1/2 phosphorylation could suppress endothelial differentiation of PDLSC.</p>

The effects of DPPI on LPS-induced periodontitis in mice / 实用口腔医学杂志

Objective:To study the effect of dipeptidyl peptidase I(DPPI)on the damage of alveolar bone and inflammatory re-sponse of periodontium in periodontitis mice.Methods:Periodontitis model of left first molars was established in 1 0 DPPI-/-mice and 1 0 wild type(WT)mice by E.coli LPS injection and the right ones were served as the control by PBS injection.Micro-CT scanning and HE staining were performed to compare the damage of alveolar bone and inflammatory response of periodontium between the 2 groups.Results:The decreace of alveolar bone height in DPPI-/-mice was less than that in WT mice〔(Maxillary:(0.001 7 ± 0.000 4)mm vs (0.202 0 ±0.008 6)mm;Mandibular:(0.034 2 ±0.002 9)mm vs (0.332 8 ±0.01 2 5)mm〕(P<0.05).HE staining showed that the inflammatory response of periodontium in DPPI-/-mice was less severe than that in WT mice.Conclusion:DPPI may promote the inflammatory response of periodontis in mice.

Effect of endoplasmic reticulum stress on the expression and osteogenic differentiation of periodontal ligament stem cells / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To determine the activity of endoplasmic reticulum stress (ERS) and its effect on osteogenic differentiation of periodontal ligament stem cells (PDLSC) in inflammatory microenvironment.</p><p><b>METHODS</b>PDLSC were obtained from the primary culture of the human tooth and cloned with limited diluted method. Real-time reverse transcription (RT)-PCR was used to examine the different expression of thapsigargin (TG) treated PDLSC and lipopolysaccharide (LPS) treated PDLSC. Real-time RT-PCR, alizarin red staining and cetyl pyridine chloride quantitative analyze were used to examine the osteogenic differentiation of PDLSC, TG + PDLSC, LPS + PDLSC and LPS + PDLSC + 4-PBA.</p><p><b>RESULTS</b>Protein kinase receptor like endoplasmic reticulum kinase (PERK), glucose regulated protein 78 (GRP78), transcription activation factor 4(ATF4), CCAAT/enhancer-binding protein-homologous protein (CHOP) mRNA expression in group PDLSC + TG in 6 h were respectively 1.49 ± 0.24, 2.77 ± 0.60, 1.75 ± 0.16, 2.16 ± 0.32, which were all greater than that in group PDLSC (P < 0.05). PERK, CHOP mRNA expression reached the peak at 6 h (1.76 ± 0.08, 2.31 ± 0.17) and were greater than group PDLSC (P < 0.05). ERS could suppress osteogenic differentiation of TG + PDLSC and LPS + PDLSC. The runt-related transcription factor-2 (RUNX2), alkaline phosphatase (ALP), osteocalcin (OCN) mRNA expression of group TG + PDLSC was respectively 0.73 ± 0.06, 0.01 ± 0.00, 0.20 ± 0.06 (P < 0.05). The RUNX2, ALP, OCN mRNA expression of group LPS + PDLSC was respectively 0.80 ± 0.06, 0.48 ± 0.05, 0.29 ± 0.04 (P < 0.05). The RUNX2, ALP, OCN mRNA expression of group PDLSC + TG + 4-PBA was respectively 1.10 ± 0.09, 0.74 ± 0.05, 0.67 ± 0.13, which were greater higher than that of group LPS + PDLSC (P < 0.05).</p><p><b>CONCLUSIONS</b>ERS was activated in PDLSC and suppressed osteogenic differentiation of PDLSC, which can simulate inflammatory microenvironment in vitro. This effect can be recovered by using ERS inhibitor 4-PBA.</p>

Treatment of recurrent aphthous ulcer with Xipayi mouthwash / 实用口腔医学杂志

100 patients with recurrent aphthous ulcer (RAU) were randomly divided into two groups, 50 in each group. The patients in test group were treated with Xipayi mouthwash, those in control were given Chlorhexidine mouthwash. All the patients were treated for 7 days. The efficacy of Xipayi mouthwash is superior to Chlorhexidine in the treatment of RAU.

Study on the Drug-loading Pattern of BMP 2 Slow-release Microspheres / 中国药房

0.05)between DA and DE when the diameter of gel microspheres was20?m～40?m.CONCLUSI_ ON:The drug-loading pattern of BMP 2 -DEX-GMA gel microspheres can be influenced by its particle size,but its drug release character can not be changed,the controlled release of drugs can be achieved through changing the nature of its drug-loading material.

Biodegradation of synthetic bioglasses with different crystallinity in vitro / 生物医学工程学杂志

SG600, SG900 and SG1100 were synthesized by the sol-gel method. Further treatments with increasing temperatures influenced and determined the crystallization degree of the material. Primary cultured osteoclasts were incubated for 4h and 48h on samples. Osteoclast actin labeling was examined by cytochemical staining. The concentrations of Ca and P in culture medium were quantified by colorimetric methods. SEM examined osteoclast morphology and resorption lacuna. Actin staining revealed on all three materials the typical adhesion contact ring. The Ca concentration in the culture medium of SG600 was significantly higher than that in control medium, SG900 and SG1100. Ca and P concentrations were always higher in culture media with the presence of osteoclasts. Morphological studies by scanning electron microsopy(SEM) showed a good adhesion behavior of osteoclasts on all three samples. Well-developed and deep resorption lacunae appearing after the osteoclastic resorption action were detected on all three samples. The synthetic bioglasses with different crystallizations caused different solubility, which seemed to have little effect on the osteoclast resorption behavior. The results of morphological studies on osteoclasts and resorption lacunae clearly demonstrate that the synthetic bioglasses are easily resorbed in vitro by osteoclasts.

An experimental study of apoptosis in epithelia of oral leukoplakia / 华西口腔医学杂志

<p><b>OBJECTIVE</b>The purpose of this study was to investigate the relationship between apoptosis and proliferation of oral mucosa in lesions of leukoplakia and the role of apoptosis in the pathogenesis of this common oral disease.</p><p><b>METHODS</b>The mucosa was obtained from the leukoplakia lesions from 6 patients, with average age of 57 years, and all the patients had not received any treatment before this investigation. The lesions were located on the lip (1), gingiva (1), tongue (2) and buccal mucosa (2). All the patients did not have any systemic diseases. Other three normal oral mucosa tissues were collected as the control. In situ terminal deoxynucleotidyl transferase end-labeling (TUNEL) and avidin-biotin peroxidase complex (ABC) immunohistochemical assay were used to detect single-strand DNA breaks and proliferating cell nuclear antigens (PCNA). The negative control slides were treated with the tris saline buffer to substitute the terminal deoxynucleotidyl transferase (TdT) and PCNA-Ab in the assay. Five consecutive high power fields with the magnification of 400 were used to search for positive stained keratinocytes.</p><p><b>RESULTS</b>Compared with the normal mucosa, the keratinocytes in leukoplakia showed positive apoptotic signals in the nucleus of suprabasal epithelial layers, while PCNA-positive stain was present in the basal position. In the connective tissue, positive apoptotic signals were found in lymphocytes and the endothelia of blood vessels.</p><p><b>CONCLUSION</b>The results indicate that the death of cells in leukoplakia is partly due to apoptosis which may play an important role in the genesis of oral leukoplakia.</p>

Effects of collagen membrane in the treatment of class Ⅱ-Ⅲ furcation defects / 实用口腔医学杂志

Objective: To evaluate the effects of guided tissue regeneration(GTR) in the treatment of degree Ⅱ-Ⅲ furcation defects with collagen membranes.Methods: 11 sites with Ⅱ-Ⅲ furcation defects were treated with collagen membranes(group of GTR); 10 sites received flap operation(group of FO). Clinical indexes, radiographs and gingival crevicular fluid(GCF) was collected before surgery and 3 months after treatment. Alkaline phosphatase(ALP) in GCF was measured. The data were analyzed statistically. Results: 3 months after surgery, the clinical parameters of PD, PFD and AL were decreased(P0.05). The decreace of the clinical parameters measured in group GTR was more than that in group FO(P

Effects of insulin on the DNA synthesis and cell cycle of human periodontal ligament cells cultured in vitro / 实用口腔医学杂志

Objective: To investigate the effects of insulin on the DNA synthesis and cell cycle distribution of human periodontal ligament cells (PDLs). Methods:PDLs were treated with insulin at the doses (U/L) of 0.01～1 000 for 72 h,DNA synthesis of the cells was measured by 3H-TdR incorporation and cell cycle distribution was studied by flow cytometer. Results : Insulin at 1 U/L to 1 000 U/L showed a significant concentration dependent stimulation of 3H thymidine uptake, and the effect of insulin at 100 ～ 1 000 U/L were not statistically different from that at 10 U/L. The percentage of PDL cells in G1 phase during exponential growth was decreased by insulin, while that in S phase and (G2+M) was increased in experimental group. Conclusion: Insulin increases DNA synthesis of PDL cells ,and stimulates the transformation of cells from G1 to S phase.

Effect of insulin-like growth factor-Ⅰ on osteocalcin secretion of periodontal ligament cells / 第二军医大学学报

Objective: To investigate the effect of insulin-like growth factor-Ⅰon osteocalcin secretion in periodontal ligament cells. Methods: Human periodontal ligament cells were cultured by tissue explant in vitro, and the concentration of osteocalcin were determined with radio-immunological method. Results: Under the condition of L-ascorbic acid and β-glycerophosphate in culture medium, human periodontal ligament cells secreted osteocalcin time-dependently and peaked at the third week; IGF-Ⅰ3.125 ng/ml，6.250 ng/ml, 12.500 ng/ml, 25.000 ng/ml could promote the secretion of osteocalcin dose dependently. Conclusion: IGF-Ⅰ can increase the secretion of osteocalcin in human periodontal ligament cells.

Scanning electronic microscope observation of bone marrow stem cells transfected by IGF-1 gene and cultured onto ostrich true bone ceramic / 实用口腔医学杂志

Objective:To evaluate the biocompatibility of insulin-like growth factor I (IGF-1) gene transfected bone marrow stem cells (MSCs) with ostrich true bone ceramic (OTBC). Methods:Rat MSCs were transfected with IGF-1 gene, and positive clones were selected by G418. The expression of IGF-1 protein in the MSCs was detected by immunocytochemical technique. The IGF-1 transfected MSCs were cultured with OTBC and the morphology of the cells was observed by scanning electronic microscope(SEM) at different time point. Results:Immunohistochemical staining suggested that the IGF-1 protein was expressed in the IGF-1 transfected MSCs. The cells adhered to OTBC and stretched well after 24 h of culture. The IGF-1 transfected MSCs proliferated on the surface of OTBC with culture time.Conclusion:The OTBC has a good biocompatibility with IGF-1 transfected MSCs.

Treatment of recurrent aphthous ulcer with amlexanox paste / 实用口腔医学杂志

0.05), on the 4th day 7.56?6.87 and 10.00?7.07 (P0.05). After therapy all the data of electrocardiogram, blood routine examination and blood biochemical test of the cases were without clinical significance. Conclusion:50 g/L amlexanox is effective and safe in the treatment of RAU.