SHED promote angiogenesis in stem cell-mediated dental pulp regeneration.

Dental pulp, plays an indispensable role in maintaining homeostasis of the tooth. Pulp necrosis always causes tooth nutrition deficiency and abnormal root development, which leads to tooth discoloration, fracture or even loss. Our previous study showed implantation of autologous SHED could regenerate functional dental pulp. However, the detailed mechanism of the implanted SHED participating in dental pulp regeneration remains unknown. In this study, we implanted SHED in a porcine dental pulp regeneration model to evaluate the regenerative effect and identify whether SHED promoted angiogenesis in regenerated dental pulp. Firstly we verified that xenogenous SHED had the ability to regenerated pulp tissue of host in vivo. Then we found the vasculature in regenerated pulp originated from implanted SHED. In addition, stem cells were isolated from regenerated dental pulp, which exhibited good multi-differentiation properties and promoted angiogenesis in pulp regeneration process and these results demonstrated that SHED promoted angiogenesis in stem cell-mediated dental pulp regeneration.

Synthesis and anti-CVB3 activity of 4-amino acid derivative substituted pyrimidine nucleoside analogues.

Seven novel 4-amino acid derivative substituted pyrimidine nucleoside analogues were designed, synthesized, and tested for their anti-CVB3 activity. Initial biological studies indicated that among these 4-amino acid derivative substituted pyrimidine nucleoside analogues, 4-N-(2'-amino-glutaric acid-1'-methylester)-1-(2'- deoxy-2'-ß-fluoro-4'-azido)-furanosyl-cytosine 2 exhibited the most potent anti-CVB activity (IC50 = 9.3 µM). The cytotoxicity of these compounds has also been assessed. The toxicity of compound 2 was similar to that of ribavirin.

SLC34A2 regulates miR-25-Gsk3ß signaling pathway to affect tumor progression in gastric cancer stem cell-like cells.

A novel paradigm in tumor biology suggests that gastric cancer progression is driven by gastric cancer stem cell-like cells (GCSCs), but molecular mechanisms regulating tumorigenic and self-renewal potential of GCSCs are still unclear. Here, we aim to investigate biological function of SLC34A2 in regulating sphere formation and tumorigenicity (both are the hallmark of CSCs) of GCSCs and its underlying mechanisms. Our findings testified that CD44+ cells which were derived from fresh primary gastric cancer samples and cell lines displayed stem cell-like features. Significantly, SLC34A2 is increased in CD44+ GCSCs compared with those in adherent counterpart from CD44+ GCSCs. On clinic, SLC34A2 is overexpressed in primary tumor tissues compared with adjacent counterparts. We showed that SLC34A2 regulated sphere formation and self-renewal properties of CD44+ GCSCs in vitro and in vivo. Mechanistic investigations revealed that Gsk3ß was the most strikingly up-regulated gene in response to SLC34A2 knockdown in GCSCs and Wnt/ß-cantenin signaling was required for SLC34A2-mediated sphere formation. Furthermore, SLC34A2 directly binds specific sites in the miR-25 promoter region and that the promoter activity is decreased after the mutation of putative SLC34A2-binding sites, indicating that SLC34A2 is required for the transcriptional induction of miR-25. Meanwhile, luciferase assays showed that miR-25 directly targeted Gsk3ß in CD44+ GCSCs. Overall, our findings define a SLC34A2-miR-25-Gsk3ß pathway in the regulation of GCSCs features and gastric cancer progression, with potential therapeutic applications in blocking their progression.

Upregulated miR-132 in Lgr5+ gastric cancer stem cell-like cells contributes to cisplatin-resistance via SIRT1/CREB/ABCG2 signaling pathway.

Cisplatin resistance has long been a major problem that restricts its use. A novel paradigm in tumor biology suggests that gastric tumor chemo-resistance is driven by gastric cancer stem cell-like (GCSCs). Growing evidence has indicated that microRNAs (miRNAs) contributes to chemo-resistance in gastric cancer (GC). Here, Lgr5+ cells derived from gastric cancer cell lines displayed stem cell-like features. Flow cytometry demonstrated the presence of a variable fraction of Lgr5 in 19 out of 20 GC specimens. By comparing the miRNA expression profiles of Lgr5+ GCSCs and Lrg5- cells, we established the upregulation of miR-132 in Lgr5+ GCSCs. The enhanced miR-132 expression correlated chemo-resistance in GC patients. Kaplan-Meier survival curve showed that patients with low miR-132 expression survived obviously longer. Functional assays results indicated that miR-132 promoted cisplatin resistance in Lgr5+ GCSCs in vitro and in vivo. Further dual-luciferase reporter gene assays revealed that SIRT1 was the direct target of miR-132. The expression of miR-132 was inversely correlated with SIRT1 in gastric cancer specimens. Furthermore, through PCR array we discovered ABCG2 was one of the downstream targets of SIRT1. Overexpression of SIRT1 down-regulated ABCG2 expression by promoting the de-acetylation of the transcription factor CREB. CREB was further activated ABCG2 via binding to the promoter of ABCG2 to induce transcription. Thus, we concluded that miR-132 regulated SIRT1/CREB/ABCG2 signaling pathway contributing to the cisplatin resistance and might serve as a novel therapeutic target against gastric cancer.

Functional Food Chemical Ingredient Strategies for Non-alcoholic Fatty Liver Disease (NAFLD) and Hepatic Fibrosis: Chemical Properties, Health Benefits, Action, and Application.

PURPOSE OF REVIEW: The liver is an important digestive gland in the body. Lifestyle and dietary habits are increasingly damaging our liver, leading to various diseases and health problems. Non-alcoholic fatty liver disease (NAFLD) has become one of the most serious liver disease problems in the world. Diet is one of the important factors in maintaining liver health. Functional foods and their components have been identified as novel sources of potential preventive agents in the prevention and treatment of liver disease in daily life. However, the effects of functional components derived from small molecules in food on different types of liver diseases have not been systematically summarized. RECENT FINDINGS: The components and related mechanisms in functional foods play a significant role in the development and progression of NAFLD and liver fibrosis. A variety of structural components are found to treat and prevent NAFLD and liver fibrosis through different mechanisms, including flavonoids, alkaloids, polyphenols, polysaccharides, unsaturated fatty acids, and peptides. On the other hand, the relevant mechanisms include oxidative stress, inflammation, and immune regulation, and a large number of literature studies have confirmed a close relationship between the mechanisms. The purpose of this article is to examine the current literature related to functional foods and functional components used for the treatment and protection against NAFLD and hepatic fibrosis, focusing on chemical properties, health benefits, mechanisms of action, and application in vitro and in vivo. The roles of different components in the biological processes of NAFLD and liver fibrosis were also discussed.

Down-regulation of platelet-derived growth factor-D expression blockades NF-κB pathway to inhibit cell proliferation and invasion as well as induce apoptosis in esophageal squamous cell carcinoma.

Substantial evidence has demonstrated that platelet-derived growth factor-D (PDGF-D) is tightly associated with the development and progression of tumors. However, its biological functions in esophageal squamous cell carcinoma (ESCC) remain to be delineated. In this study, we found that expressions of PDGF-D mRNA and protein in ESCC tissues and cells were significantly higher than that in normal esophageal epithelial tissues (P < 0.05), further investigation showed that PDGF-D protein level in EC1 cells was obviously higher than those in EC9706 and Eca109 cells (P < 0.05). Elevated PDGF-D level was closely associated with TNM staging, tumor differentiation and lymph node metastasis (P < 0.05), but not related to the patients' age and gender (P > 0.05). In addition, down-regulation of PDGF-D expression markedly inhibited proliferation, reduced invasion and induced apoptosis in EC1 cells. More importantly, reduced PDGF-D level evoked the down-regulation of p65 and p-IκBα proteins and elevation of IκBα protein of NF-κB pathway, accompanied with the decreases of bcl-2 and MMP-9 protein expressions and increases of bax protein level and caspase-3 activities. Correctively, our data suggest that PDGF-D plays pivotal roles in the development and progression of ESCC, and combinations with PDGF-D and NF-κB pathway may be effective and feasible molecular targets for therapy of ESCC.

[Effect of silencing AEG-1 with small interfering RNA on the proliferation and cell cycle of gastric carcinoma SGC-7901 cells].

OBJECTIVE: To explore the effect of down-regulation of astrocyte elevated gene-1 (AEG-1) expression on cell proliferation and cell cycle of gastric carcinoma cells, and its possible molecular mechanism. METHODS: Control siRNA and AEG-1 siRNA were transfected into gastric carcinoma SGC-7901 cells. 48 h after transfection, the cells were divided into 3 groups including untransfected, siRNA control and AEG-1 siRNA transfection groups. Expressions of AEG-1 mRNA and protein in the 3 group cells were detected by real-time quantitative PCR and Western blot. The changes of cell proliferation were examined using CCK-8 kit, and the cell cycle distribution was detected by flow cytometry. Finally, expressions of cell proliferation and cell cycle related proteins were detected by Western blot. RESULTS: Real-time quantitative PCR and Western blot demonstrated that compared with the untransfected and siRNA control groups, expressions of AEG-1 mRNA and protein were significantly down-regulated in the AEG-1 siRNA transfection group (P < 0.05), but there was no significant difference between the untransfected and siRNA control groups (P > 0.05). Furthermore, in vivo experiment confirmed a significant down-regulation of AEG-1 protein in the AEG-1 siRNA transfection group (P < 0.05). In addition, AEG-1 siRNA obviously inhibited the proliferation of SGC-7901 cells at different time points after transfection with AEG-1 siRNA. The percentage of cells in G0/G1 phase in the AEG-1 siRNA transfection group [(61.26 ± 1.25)%] was significantly higher than those in the untransfected group [(46.17 ± 1.91)%] and siRNA control group [(46.46 ± 1.96)%], and there was a significant difference between them (all P < 0.001). Furthermore, the result of Western blotting revealed that down-regulation of AEG-1 expression evoked the down-regulation of cdk2 and cyclin D1 expressions and elevation of p21 expression in vitro and in vivo. CONCLUSIONS: The inhibition of cell proliferation and cell cycle arrest mediated by down-regulation of AEG-1 expression may be closely associated with the changes of expression of cell cycle related proteins including cdk2, cyclin D1 and p21.

Short and long-term efficacy of combining Fuzhengliqi mixture with acupuncture in treatment of functional constipation.

OBJECTIVE: To explore the short and long-term efficacy of combining Fuzhengliqi mixture (FLM) with acupuncture in treating functional constipation (FC). METHODS: The 560 patients with confirmed diagnosis of FC were randomly assigned to four groups: FLM group, acupuncture group, combined therapy group, and control group. There were 140 cases in each group. The FLM group was administered FLM 60 mL twice a day, while the acupuncture group was treated with acupuncture at acupoints Tianshu (ST 25), Shangjuxu (ST 37), Zusanli (ST 36), Dachangshu (BL 25), and Zhigou (TE 6) twice a day, the combined therapy group with FLM and acupuncture, and the control group was administered mosapride (5 mg thrice a day) and Macrogol 4000 (10 g twice a day). The treatment lasted 6 weeks. The defecation interval, stool property, constipation symptoms, and accompanying symptoms were recorded, graded, and scored. The gastrointestinal transit time (GITT) and motilin (MTL) level in serum and life quality score were detected at three time points (pre-treatment, at the end of treatment, and 60 weeks post-treatment). Moreover, the adverse reactions were also observed. RESULTS: In the FLM group 2 cases were eliminated for not taking medication strictly according to the research plan and 1 case was lost to follow-up, while 2 cases in the acupuncture group and 2 cases in the combined therapy group were lost to follow-up. Compared with those detected pre-treatment, the defecation interval, stool property, constipation symptom grade, accompanying symptom grade, and GITT were all decreased markedly at the end of treatment in every group, while the MTL levels in serum and life quality score were increased markedly (P < 0.01), the above-mentioned detecting indices were better in the combined therapy group than those in other groups (P < 0.05). Compared with the end of treatment, above-mentioned detecting indices all recurred significantly in the FLM group and control group 60 weeks post-treatment (P > 0.05), but these indices recurred insignificantly in the acupuncture and combined therapy groups (P > 0.05). The short and long-term total effective rates in the combined therapy group were significantly different from those in other groups (P < 0.05 or P < 0.01). No serious adverse reactions were found in four groups. CONCLUSION: Both FLM and acupuncture can significantly shorten the defecation interval and GITT, increase MTL levels in serum, decrease the scores of stool property, constipation symptoms, and accompanying symptoms in patients with FC to increase their life quality. The combined therapy is much better in long-term efficacy and the safety is also good, worth spreading in clinical practice.

The Incidence and Risk Factors of Acute Myocardial Infarction Among Patients with Gastrointestinal bleeding: A Retrospective Study.

Purpose: Patients with gastrointestinal bleeding (GIB) and acute myocardial infarction (AMI) have higher mortality than that with either GIB or AMI alone. The aims of this study were to determine the incidence and risk factors of AMI in patients with GIB. Patients and Methods: From January 2015 to January 2018, we retrospectively studied 1287 patients with GIB in Renmin Hospital of Wuhan University. Various demographic, laboratory and outcome data were reviewed by charts. Results: Thirty-seven patients had AMI and were placed in AMI group and the rest 1250 patients were in non-AMI group. Patients with AMI were more likely to be older than 70 years, have hypertension, coronary heart disease, chronic kidney disease, and have the recent history of taking aspirin before admission. The ROC curve of hemoglobin (HB) on admission showed area under curve was 0.762, the optimal cut-off value is 76.5g/L. Logistic regression analysis showed that age ≥ 70 years old, coronary heart disease and HB < 76.5g/L on admission were independent risk factors of AMI in patients with GIB. The mortality of patients during hospitalization in AMI group and in non-AMI group were 45.95% and 5.48%, respectively. Patients who displayed a history of liver disease and HB < 76.5g/L on admission had a higher death rate. Conclusion: GIB increased the risk of subsequent AMI, especially in patients over 70 years old, with history of coronary heart disease and HB < 76.5g/L on admission. Patients with GIB and AMI who had history of liver disease and HB < 76.5g/L on admission had a higher mortality rate. Clinicians should identify the high-risk patients of AMI among the GIB population early and prevent AMI.

Amyloid-mediated remineralization for tooth hypoplasia of cleidocranial dysplasia.

Introduction: Cleidocranial dysplasia (CCD) is an autosomal-dominant, heritable skeletal and dental disease, involving hypoplastic clavicles, defective ossification of the anterior fontanelle, dentin and enamel hypoplasia, and supernumerary teeth, which can seriously affect the oral and mental health of patients. Amyloid-like protein aggregation, which is established by lysozyme conjugated with polyethylene glycol (Lyso-PEG), forms a mineralized nanofilm layer on a healthy enamel surface. However, whether it can form a remineralization layer in dental tissues from CCD remains unclear. Methods: This study evaluated deciduous teeth from healthy individuals and a patient with CCD. Because pulp and dentin are functionally closely related, stem cells from human exfoliated deciduous teeth (SHED) from CCD patients and healthy individuals were collected to compare their biological properties. Results: The results found that deciduous teeth from patients with CCD exhibited dentin hypoplasia. In addition, the proliferative ability and osteogenic potential of SHED from patients with CCD were lower than those of control individuals. Finally, Lyso-PEG was applied to dentin from the CCD and control groups, showing a similar remineralization-induced effect on the dentin surfaces of the two groups. Conclusion: These results extend our understanding of the dentin and SHED of patients with CCD, exhibiting good caries-preventive capacity and good biocompatibility of Lyso-PEG, thus providing a novel dental therapy for CCD and patients with tooth hypoplasia.

Changes in nitrogen metabolism of phosphorus-starved bloom-forming cyanobacterium Microcystis aeruginosa: Implications for nutrient management.

The surplus of nitrogen plays a key role in the maintenance of cyanobacterial bloom when phosphorus has already been limited. However, the interplay between high nitrogen and low phosphorus conditions is not fully understood. Nitrogen metabolism is critical for the metabolism of cyanobacteria. Transcriptomic analysis in the present study suggested that nitrogen metabolism and ribosome biogenesis were the two most significantly changed pathways in long-term phosphorus-starved bloom-forming cyanobacteria Microcystis aeruginosa FACHB-905. Notably, the primary glutamine synthetase/glutamate synthase cycle, crucial for nitrogen metabolism, was significantly downregulated. Concurrently, nitrogen uptake showed a marked decrease due to reduced expression of nitrogen source transporters. The content of intracellular nitrogen reservoir phycocyanin also showed a drastic decrease upon phosphorus starvation. Our study demonstrated that long-term phosphorus-starved cells also suffered from nitrogen deficiency because of the reduction in nitrogen assimilation, which might be limited by the reduced ribosome biogenesis and the shortage of adenosine triphosphate. External nitrogen supply will not change the transcriptions of nitrogen metabolism-related genes significantly like that under phosphorus-rich conditions, but still help to maintain the survival of phosphorus-starved cells. The study deepens our understanding about the survival strategies of Microcystis cells under phosphorus starvation and the mutual dependence between nitrogen and phosphorus, which would provide valuable information for nutrient management in the eutrophicated water body.

Comparison of autologous bone marrow mononuclear cells transplantation and mobilization by granulocyte colony-stimulating factor in experimental spinal injury.

BACKGROUND: Recent studies have shown that autologous adult stem cells may be a protocol of treatment for spinal cord injury (SCI) in humans. The purpose of this study was to compare the effect of an injection of autologous bone marrow mononuclear cells (BMMCs) and bone-marrow cell mobilization induced by granulocyte colony stimulating factor (G-CSF) in rats with SCI. METHODS: Adult rats were assigned into three groups: control group (SCI only), SCI + BMMCs, and SCI + G - CSF. Neurological scores and electrophysiological testing were done in all rats before SCI, and at 1, 7, 14, 28, 56 days post-SCI. Simultaneously, immunohistochemical labeling and TUNEL assay were performed at the given time. RESULTS: From 1 week post-SCI onward, animals treated with BMMCs or G-CSF had higher BBB scores than control group. Motor and somatosensory evoked potentials (MEPs and SEPs, respectively) of the treated group were significantly better than those in control group at 2 weeks. After sacrifice, compared with the control, animals treated with BMMCs and G-CSF significantly increased expressions of Brdu, NSE, GFAP, Factor VIII, BDNF, and reduced expression of apoptosis cells around the lesion site. Our results indicate that administration of BMMCs and G-CSF in a SCI model achieves similarly positive effect on functional and histologic recovery. CONCLUSIONS: The use of G-CSF may be a viable alternative to BMMCs for autograft in patients with SCI.

Clinical curative effect of electroacupuncture combined with zhizhukuanzhong capsules for treating gastroesophageal reflux disease.

OBJECTIVE: To study the clinical curative effect, safety and mechanism of action of electroacupuncture combined with Zhizhukuanzhong capsules (ZZKZC) in treating gastroesophageal reflux disease (GERD). METHODS: A total of 480 patients with confirmed GERD were randomly divided into four groups: the electroacupuncture group, the ZZKZC group, the combined therapy group, and the control group, with 120 cases in each group. Each case in the electroacupuncture group was treated with electroacupuncture on Zusanli (ST 36), Zhongwan (CV 12), Neiguan (PC 6),Taichong (LR 3) and Gongsun (SP 4) once daily for 6 weeks. Each case in the ZZKZC group was treated with oral administration of 1.29 g ZZKZC three times daily. The combined therapy group had electroacupuncture and ZZKZC. The control group was given oral administration of 5 mg mosapride three times and 20 mg pantoprazole twice daily. The 24-hour intraesophageal total number of reflux episodes with pH <4 (or bilirubin absorbance > or = 0.14), the number of long-term (> or = 5 min) reflux episodes, the percentage of upright time, the percentage of supine time, the percentage of total time of pH <4 (or bilirubin absorbance > or = 0.14), endoscopic grading score, symptom score, quality of life score, and adverse reactions were observed before treatment, at the end of treatment and 54 weeks after treatment in the four groups. RESULTS: The 24-hour intraesophageal pH and bile reflux, endoscopic grading score and symptom score were all significantly decreased at the end of treatment in every group, while the scores of 8 dimensions of quality of life were all increased compared with those before treatment (P<0.01). All of these indices were better in the combined therapy group than those in the other groups (P<0.05). These indices did not significantly deteriorate in the combined therapy group and electroacupuncture group 54 weeks after treatment compared with the end of treatment (P>0.05); however, these indices all significantly deteriorated in the ZZKZC and control groups (P>0.05). The short and long-term total efficacy rates in the combined therapy group showed significant superiority to those in the other groups (P<0.05 or P<0.01). No serious adverse reactions were found in the four groups. CONCLUSION: Electroacupuncture and ZZKZC play an important role in inhibiting intraesophageal acid and bile reflux, decreasing the endoscopic grading score, and alleviating the symptoms of gastroesophageal reflux to improve the quality of life. However, the effect of combined treatment is more effective, with better security and long-term efficacy, and therefore, this combination treatment is appropriate for clinical use.

[Effects of KIAA0101 expression on proliferation and invasion of gastric carcinoma MKN-45 cells].

OBJECTIVE: To investigate the expression of KIAA0101 protein in gastric carcinoma cells, and to explore the effects of its down-regulation on the cell proliferation, cell cycle and invasion. METHODS: Western blot was used to detect KIAA0101 protein expression in three gastric carcinoma cell lines including MKN-28, SGC-7901 and MKN-45. KIAA0101 siRNA and control siRNA were utilized to transfect MKN-45 cells, respectively. CCK-8 was used to analyze the changes of cell proliferation, and flow cytometry to examine the changes of cell cycle distribution. Finally, Boyden chamber was used to detect the ability of cell invasion. RESULTS: Relative level of KIAA0101 protein in MKN-45 cells was significantly higher than those in MKN-28 and SGC-7901 cells, and there was significant difference among the three cell lines (P < 0.05). The result of CCK-8 study demonstrated that, compared with untreated group and control siRNA group, the proliferation of MKN-45 cells in KIAA0101 siRNA group was significantly inhibited (P < 0.05). Additionally, the result of cell cycle analysis revealed that the percentage of cell number in G(0)/G(1) phase in KIAA0101 siRNA group [(61.47 ± 0.89)%] was significantly higher than those in untreated group [(47.43 ± 0.85)%] and control siRNA group [(48.43 ± 0.73)%; F = 271.653, P = 0.000]. Further, Boyden chamber assay showed that the cell numbers migrated to Matrigel in KIAA0101 siRNA group (61.51 ± 4.76) were significantly lower than those in untreated group (138.74 ± 10.16) and control siRNA group (132.93 ± 11.25; F = 65.949, P = 0.000). CONCLUSIONS: Down-regulation of KIAA0101 expression leads to an inhibition of cell proliferation, cell cycle and cell invasion. It may provide a novel target for the treatment of patients with gastric carcinoma.

The Effects of Multi-Donor Fecal Microbiota Transplantation Capsules Combined with Thalidomide on Hormone-Dependent Ulcerative Colitis.

Objective: This study aimed to assess the effects of multi-donor fecal microbiota transplantation (FMT) capsules combined with thalidomide on hormone-dependent ulcerative colitis (UC). Methods: A total of 59 patients with steroid-dependent UC treated at the Gastroenterology Department of the First Affiliated Hospital of Xinxiang Medical University between January 2017 and January 2019 were enrolled in this study. Using a random number table, the patients were divided into two groups: a group treated with FMT capsules (the FMT group) and a group treated with FMT capsules and thalidomide (the FMT+S group). Multi-donor FMT capsules were prepared, and all subjects and stool donors followed the FMT pathway for FMT transplantation. Each patient's Mayo score, C-reactive protein (CRP) level, and level of fecal calprotectin before FMT treatment and at week 1 and week 13 after treatment were recorded. All patients were followed up for 15 weeks. Results: A total of 56.7% of the patients (34/59) achieved a therapeutic response at the end of the research period. Compared with the FMT group, the FMT+S group had better clinical benefit (P < 0.05). In the comparison of efficacy at week 1 and week 13 after treatment, the Mayo scores, calprotectin levels, and CRP indexes in the FMT+S group were better than those in the FMT group (P < 0.05). There were no serious adverse events in the treatment process or during follow-up. Conclusion: A combination of FMT capsules and thalidomide provides a treatment choice for patients with hormone-dependent UC, and it can be used as an adjuvant therapy. However, large-scale, multi-center, and prospective trials are required to further verify the reliability of this treatment.

Amyloid-Mediated Remineralization in Pit and Fissure for Caries Preventive Therapy.

The pits and fissures of teeth have high caries susceptibility, and sealing these areas is considered as an effective method to prevent caries. However, long-term caries prophylaxis cannot be maintained because of the negative effects derived from the technical sensitivity and disadvantages of sealing materials. Herein, a new strategy is proposed to occlude fossae by amyloid-mediated biomimetic remineralization. In contrast to conventional inward blocking from the outside of fossae, amyloid-mediated biomimetic mineralization delivers an amyloid-like protein nanofilm into the deepest zone of the fossae and induces the formation of remineralized enamel inside. Such assembly from lysozyme conjugated with poly (ethylene glycol) enriches the interface with strongly bonded ionsand directs in situ nucleation to achieve enamel epitaxial growth. Not only is the structure of the enamel-like crystalline hydroxyapatite layer but also its mechanical stability is similar to that of natural enamel. Furthermore, the layer shows good biocompatibility and antibacterial properties. On the basis of the findings, it is demonstrated that amyloid-like protein aggregation may provide an enamel remineralization strategy to modify the current clinically available methods of pit and fissure sealing and shows great promise in preventing caries.

Synthesis and anti-HIV-1 activity of 4-substituted-7-(2'-deoxy-2'-fluoro-4'-azido-ß-D-ribofuranosyl)pyrrolo[2,3-d]pyrimidine analogues.

Three novel 4-subsituted-7-(2'-deoxy-2'-fluoro-4'-azido-ß-D-ribofuranosyl)pyrrolo[2,3-d]pyrimidine analogues were designed, synthesized, and tested for their anti-HIV-1 activity. Initial biological studies indicated that among these pyrrolo[2,3-d]pyrimidine ribonucleoside analogues, 4-amino-7-(2'-deoxy-2'-fluoro-4'-azido-ß-D-ribofuranosyl)pyrrolo[2,3-d]pyrimidine 10 exhibited the most potent anti-HIV-1 activity (EC(50)=0.5±0.3 µM), while 4-hydroxy-7-(2'-deoxy-2'-fluoro-4'-azido-ß-D-ribofuranosyl)pyrrolo[2,3-d] pyrimidine 9 and 4-amino-5-fluoro-7-(2'-deoxy-2'-fluoro-4'-azido-ß-D-ribofuranosyl)pyrrolo[2,3-d] pyrimidine 11 showed moderate activity (EC(50)=13±8 and 5.4±0.3 µM, respectively). The cytotoxicity of these compounds has also been assessed. No significant cytotoxicities were found for any of these compounds with concentrations up to 25 µM.

SHED aggregate exosomes shuttled miR-26a promote angiogenesis in pulp regeneration via TGF-ß/SMAD2/3 signalling.

OBJECTIVES: Pulp regeneration brings big challenges for clinicians, and vascularization is considered as its determining factor. We previously accomplished pulp regeneration with autologous stem cells from deciduous teeth (SHED) aggregates implantation in teenager patients, however, the underlying mechanism needs to be clarified for regenerating pulp in adults. Serving as an important effector of mesenchymal stem cells (MSCs), exosomes have been reported to promote angiogenesis and tissue regeneration effectively. Here, we aimed to investigate the role of SHED aggregate-derived exosomes (SA-Exo) in the angiogenesis of pulp regeneration. MATERIALS AND METHODS: We extracted exosomes from SHED aggregates and utilized them in the pulp regeneration animal model. The pro-angiogenetic effects of SA-Exo on SHED and human umbilical vein endothelial cells (HUVECs) were evaluated. The related mechanisms were further investigated. RESULTS: We firstly found that SA-Exo significantly improved pulp tissue regeneration and angiogenesis in vivo. Next, we found that SA-Exo promoted SHED endothelial differentiation and enhanced the angiogenic ability of HUVECs, as indicated by the in vitro tube formation assay. Mechanistically, miR-26a, which is enriched in SA-Exo, improved angiogenesis both in SHED and HUVECs via regulating TGF-ß/SMAD2/3 signalling. CONCLUSIONS: In summary, these data reveal that SA-Exo shuttled miR-26a promotes angiogenesis via TGF-ß/SMAD2/3 signalling contributing to SHED aggregate-based pulp tissue regeneration. These novel insights into SA-Exo may facilitate the development of new strategies for pulp regeneration.

Odontogenesis-related developmental microenvironment facilitates deciduous dental pulp stem cell aggregates to revitalize an avulsed tooth.

Harnessing developmental processes for tissue engineering represents a promising yet challenging approach to regenerative medicine. Tooth avulsion is among the most serious traumatic dental injuries, whereas functional tooth regeneration remains uncertain. Here, we established a strategy using decellularized tooth matrix (DTM) combined with human dental pulp stem cell (hDPSC) aggregates to simulate an odontogenesis-related developmental microenvironment. The bioengineered teeth reconstructed by this strategy regenerated three-dimensional pulp and periodontal tissues equipped with vasculature and innervation in a preclinical pig model after implantation into the alveolar bone. These results prompted us to enroll 15 patients with avulsed teeth after traumatic dental injuries in a pilot clinical trial. At 12 months after implantation, bioengineered teeth led to the regeneration of functional teeth, which supported continued root development, in humans. Mechanistically, exosomes derived from hDPSC aggregates mediated the tooth regeneration process by upregulating the odontogenic and angiogenic ability of hDPSCs. Our findings suggest that odontogenic microenvironment engineering by DTM and stem cell aggregates initiates functional tooth regeneration and serves as an effective treatment for tooth avulsion.

Gli1+ Cells Residing in Bone Sutures Respond to Mechanical Force via IP3R to Mediate Osteogenesis.

Early orthodontic correction of skeletal malocclusion takes advantage of mechanical force to stimulate unclosed suture remodeling and to promote bone reconstruction; however, the underlying mechanisms remain largely unclear. Gli1+ cells in maxillofacial sutures have been shown to participate in maxillofacial bone development and damage repair. Nevertheless, it remains to be investigated whether these cells participate in mechanical force-induced bone remodeling during orthodontic treatment of skeletal malocclusion. In this study, rapid maxillary expansion (RME) mouse models and mechanical stretch loading cell models were established using two types of transgenic mice which are able to label Gli1+ cells, and we found that Gli1+ cells participated in mechanical force-induced osteogenesis both in vivo and in vitro. Besides, we found mechanical force-induced osteogenesis through inositol 1,4,5-trisphosphate receptor (IP3R), and we observed for the first time that inhibition of Gli1 suppressed an increase in mechanical force-induced IP3R overexpression, suggesting that Gli1+ cells participate in mechanical force-induced osteogenesis through IP3R. Taken together, this study is the first to demonstrate that Gli1+ cells in maxillofacial sutures are involved in mechanical force-induced bone formation through IP3R during orthodontic treatment of skeletal malocclusion. Furthermore, our results provide novel insights regarding the mechanism of orthodontic treatments of skeletal malocclusion.