Regulation of endothelial cells on the osteogenic ability of bone marrow mesenchymal stem cells in peri-implantitis.

OBJECTIVES: The relationship between bone resorption and angiogenesis in peri-implantitis remains to be studied. We constructed a Beagle dog model of peri-implantitis, and extracted bone marrow mesenchymal stem cells (BMSCs) and endothelial cells (ECs) for culture. The osteogenic ability of BMSCs in the presence of ECs was investigated through an in vitro osteogenic induction model, and its mechanism was initially explored. SUBJECTS AND METHODS: The peri-implantitis model was verified by ligation, bone loss was observed by micro-CT, and cytokines were detected by ELISA. The isolated BMSCs and ECs were cultured to detect the expression of angiogenesis, osteogenesis-related proteins, and NF-κB signaling pathway-related proteins. RESULTS: 8 weeks after surgery, the peri-implant gums were swollen, and micro-CT showed bone resorption. Compared with the control group, IL-1ß, TNF-α, ANGII and VEGF were markedly increased in the peri-implantitis group. In vitro studies found that the osteogenic differentiation ability of BMSCs co-cultured with IECs was decreased, and the expression of NF-κB signaling pathway-related cytokines was increased. CONCLUSION: Endothelial cells inhibit the osteogenic differentiation of bone marrow mesenchymal stem cells through NF-κB signaling in the environment of peri-implantitis, which may become a new target for the treatment of peri-implantitis.

Clinical study of dynamic real-time navigation assisted immediate implant without flapping in the esthetic zone.

OBJECTIVE: The purpose of this study is to investigate the clinical effect of Dynamic real-time navigation to assist immediate implant without flapping in the esthetic zone. METHODS: Eight patients who underwent immediate implantation in the aesthetic area were included. A total of 11 implants were implanted using dynamic real-time navigation system combined with non-flap technology. Clinical indicators including implant deviation, initial stability, alveolar bone absorption, implant success rate, pink esthetic score (PES), Papilla index score (PIS), and the thickness of labial side bone plate of the implant were recorded. RESULTS: The deviation between the actual implant position and the preoperative design was (0.76±0.08) mm at the top, (1.11±0.18) mm at the root, (0.90±0.16) mm at the depth, and (1.48±0.91)°at the Angle. ISO values of all implants were greater than 59. PES was greater than 8. PIS index was 2 or 3. The average alveolar bone absorption was (0.34±0.09) mm and the thickness of bone plate on the lip of implant was greater than 1.6 mm. The success rate of implantation was 100%. CONCLUSION: The use of dynamic real-time navigation assisted non-flap implantation in the aesthetic area can effectively reduce implant deviation and improve the aesthetic effect.

A comparative study of the morphology and molecular biology between the Schneiderian membrane and palatine mucoperiosteum.

Schneiderian membrane is an indispensable structure for osteogenesis under the sinus floor space after maxillary sinus floor elevation.Therefore,this study aimed to compare the Schneiderian membrane and palatine mucoperiosteum in various aspects to explore whether the Schneiderian membrane has a periosteal layer and osteogenic ability. Schneiderian membrane and palatine mucoperiosteum specimens were collected and stained with HE, Masson, and Sirius red. Immunofluorescence staining was used to observe the expression and localization of mesenchymal stem cells (MSCs). Then MSCs from two tissues were isolated,cultured, and identified. The expression of osteogenic markers OCN, RUNX2, and BMP2 ware detected by Western blotting and quantitative PCR after osteogenic differentiation.The morphological observations revealed both the Schneiderian membrane and palatine mucoperiosteum were composed of three layers.Immunofluorescence staining showed that the inner bone surface layer of the Schneiderian membrane was rich in MSCs, which was similar to the cambium layer of the palatine mucoperiosteum.In addition, MSCs from two tissues showed similar morphological phenotype. After further osteogenic induction of the two groups, the expression of BMP2, RUNX2, and OCN were significantly increased. This study provide a novel insight into that Schneiderian membrane is a mucoperiosteal membrane rich of MSCs, containing a periosteal layer and osteogenic ability similar to mucoperiosteum.

Changes in gene expression in rat placenta at gestational day 16.5 in response to hyperglycemia.

Gestational diabetes mellitus (GDM) is a serious pregnancy complication. Hyperglycemia induces abnormal placental development and function. However, the mechanism is unclear. Previous research showed streptozocin (STZ) injection sustained hyperglycemia throughout pregnancy in rodents. Our current results showed that the placenta from hyperglycemic STZ-treated rats was about 20% heavier than that of controls. The relative thickness of each layer of the placenta was also significantly different on gestational day (GD) 16.5. Gene expression was analyzed by RNA sequencing to explore reasons for the abnormal placenta. In total, 2100 differential expressed genes (DEGs), including 1327 up-regulated and 773 down-regulated genes, were identified. Gene ontogeny (GO) analysis revealed DEGs involved in developmental process, growth, metabolic process, cell junction, molecular transducer activity and signaling. By KEGG analysis, DEGs were mainly related to the endocrine system, development, signal transduction and cell growth and death. The KEGG results were partly consistent with GO results, with DEGs mainly focused on biochemical signal pathways such as cell growth and death (e.g., Abl1, Bbc3 and Camk2d), and signal transduction (e.g., Abl1, Ceacam1 and Arnt). These genes may play a dominant role in abnormal cell proliferation and signaling disorders. These results suggest that DEGs play a role in diabetic-induced placental abnormalities. One or more of these DEGs may be involved in the etiology of placental weight increase caused by hyperglycemia.

Mid-pregnancy consumption of fruit, vegetable and fruit juice and the risk of gestational diabetes mellitus: A correlation study.

OBJECTIVE: To determine the potential association between mid-pregnancy consumption of fruit, vegetable and fruit juice and the risk of gestational diabetes mellitus (GDM). RESEARCH DESIGN AND METHODS: An observational study with 2987 pregnant women was conducted in China from June 2013 to June 2014. Fruit, vegetable and fruit juice consumption during weeks 13-28 of pregnancy was assessed by using 24 h dietary recall method and food frequency questionnaire. Cox proportional hazard model was used to assess the association between fruit, vegetable and fruit juice consumption (in quartiles) and GDM risks, and One-Way ANOVA was used to compare the incidences of GDM at various levels of fruit, vegetable and fruit juice consumption, adjusted for gestational age, family history of diabetes, physical activity, fiber and meat intake. RESULTS: Among all the 2987 pregnant women, 405 (13.6%) were diagnosed as GDM for the first time. There was no association between total fruit and vegetable consumption and GDM. Quantity of grape, melon, potatoes and fruit juice consumption were positively associated with the incidence of GDM. In contrast, quantity of apple, orange and vegetables other than potatoes were negatively associated with the incidence of GDM. CONCLUSIONS: Our findings indicate that appropriate quantity of fruit and vegetable intakes throughout pregnancy may have a beneficial effect on preventing the development of GDM, whereas excess consumption of fruits, potatoes and fruit juices is associated with an increased risk of GDM.

LINC00968 promotes osteogenic differentiation in vitro and bone formation in vivo via regulation of miR-3658/RUNX2.

Osteogenic differentiation of dental pulp stem cells (DPSCs) is considered as a promising strategy in posterior maxilla tooth implantation. Information on the function and mechanisms of long non-coding RNAs (lncRNAs) in osteogenic differentiation of DPSCs is growing, however, the mechanism of LINC00968 and miR-3658 in regulating osteogenic differentiation of DPSCs still needs to be explored. In this study, the LINC00968 and miR-3658 expression level was upregulated and downregulated in DPSCs and peri-implantitis DPSCs (pDPSCs) treated with bone morphogenic protein (BMP)2, respectively. Moreover, the effects of LINC00968 and miR-3658 on BMP2-induced osteogenic differentiation of DPSCs in vitro using Alizarin Red S staining, alkaline phosphatase (ALP) activity, quantitative real time PCR and Western blot assays showed that overexpression of LINC00968 significantly promoted mineralized bone matrix, alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX2), and osterix (OSX) expression levels for osteogenic differentiation of DPSCs and pDPSCs; and overexpression of miR-3658 showed an opposite result that inhibited osteogenic differentiation of DPSCs and pDPSCs. Luciferase reporter assay showed that luciferase activities of LINC00968-WT reporter and RUNX2-WT reporter were strongly suppressed by miR-3658 overexpression. In addition, the miR-3658 upregulation interfered ectopic bone formation in vivo stimulated by LINC00968. In general, we had identified a novel molecular pathway involving LINC00968/miR-3658/RUNX2 during DPSCs and pDPSCs differentiation into osteoblasts, which might facilitate bone anabolism.

Progesterone impairs antigen-non-specific immune protection by CD8 T memory cells via interferon-γ gene hypermethylation.

Pregnant women and animals have increased susceptibility to a variety of intracellular pathogens including Listeria monocytogenes (LM), which has been associated with significantly increased level of sex hormones such as progesterone. CD8 T memory(Tm) cell-mediated antigen-non-specific IFN-γ responses are critically required in the host defense against LM. However, whether and how increased progesterone during pregnancy modulates CD8 Tm cell-mediated antigen-non-specific IFN-γ production and immune protection against LM remain poorly understood. Here we show in pregnant women that increased serum progesterone levels are associated with DNA hypermethylation of IFN-γ gene promoter region and decreased IFN-γ production in CD8 Tm cells upon antigen-non-specific stimulation ex vivo. Moreover, IFN-γ gene hypermethylation and significantly reduced IFN-γ production post LM infection in antigen-non-specific CD8 Tm cells are also observed in pregnant mice or progesterone treated non-pregnant female mice, which is a reversible phenotype following demethylation treatment. Importantly, antigen-non-specific CD8 Tm cells from progesterone treated mice have impaired anti-LM protection when adoptive transferred in either pregnant wild type mice or IFN-γ-deficient mice, and demethylation treatment rescues the adoptive protection of such CD8 Tm cells. These data demonstrate that increased progesterone impairs immune protective functions of antigen-non-specific CD8 Tm cells via inducing IFN-γ gene hypermethylation. Our findings thus provide insights into a new mechanism through which increased female sex hormone regulate CD8 Tm cell functions during pregnancy.

Changes of nerve growth factor in amniotic fluid and correlation with ventriculomegaly.

OBJECTIVE: To detect the change of nerve growth factor (NGF) level in human amniotic fluid during gestation, and to explore the relationship between this change and fetal ventriculomegaly (VM). METHODS: The studied subjects (collected from 2004 to 2007) were divided into four groups, including the second-trimester pregnancy group (n=113), third-trimester pregnancy group (n=110), fetal cerebral VM group (n=12), and healthy control group (n=12) which matched with the VM group in gestational weeks. The amniotic fluid specimens were obtained during amniocentesis or cesarean section. The NGF levels in amniotic fluid were detected with enzyme-linked immunosorbent assay. RESULTS: A significantly negative correlation was found between gestational age and the NGF level in amniotic fluid (r=−0.6149, P<0.0001). The NGF level in patients with fetal VM was significantly lower than that in healthy controls (33.95±29.24 pg/mL vs. 64.73±16.21 pg/mL, P=0.024). CONCLUSION: NGF levels in amniotic fluid may be a sensitive marker for fetal VM.

Effects of graded hypothermia on hypoxic-ischemic brain damage in the neonatal rat.

OBJECTIVE: To investigate the effect of graded hypothermia on neuropathologic alterations of neonatal rat brain after exposed to hypoxic-ischemic insult at 37°C, 33°C, 31°C, and 28°C, respectively, and to observe the effect of hypothermia on 72-kDa heat shock protein (HSP72) expression after hypoxic-ischemic insult. METHODS: Seven days old Wistar rats were subjected to unilateral common carotid artery ligation followed by exposure to hypoxia in 8% oxygen for 2 hours at 37°C, 33°C, 31°C, and 28°C, respectively. The brain temperature was monitored indirectly by inserting a mini-thermocouple probe into the temporal muscle during hypoxia. After hypoxia-ischemia their mortality was assessed. Neuronal damage was assessed with HE staining 72 hours after hypoxia. HSP72 expression at 0.5, 24, and 72 hours of recovery was immunohistochemically assessed using a monoclonal antibody to HSP72. RESULTS: Hypoxia-ischemia caused 10.5% (2/19) of mortality in rat of 37°C group, but no death occurred in 33°C, 31°C or 28°C groups. HE staining showed neuropathologic damage was extensive in rats exposed to hypoxia-ischemia at 37°C (more than 80.0%). The incidence of severe brain damage was significantly decreased in 33°C (53.3%) and 31°C groups (44.4%), and no histologic injury was seen in the 28°C group of rats. Expression of HSP72 was manifest and persistent in the rat brain of 37°C group, but minimum in the rat brain of 28°C group. CONCLUSION: Mild and moderate hypothermia might prevent cerebral visible neuropathologic damage associated with hypoxic-ischemic injury by decreasing stress response.

Effect of propentofylline on hypoxic-ischaemic brain damage in newborn rat.

BACKGROUND: Studies showed that propentofylline enhances the action of adenosine and protects hippocampal neuronal damage against transient global cerebral ischaemia. Our study was to investigate the effect of propentofylline on hypoxic-ischaemic brain damage in neonatal rat. METHODS: Seven-day-old Wistar rats were subjected to unilateral common carotid artery ligation and hypoxia in oxygen 8 kPa for two hours at 37 degrees C. Propentofylline (10 mg/kg) was administered intraperitoneally one hour after hypoxia-ischaemia (treated group). Control group rats were received an equivalent volume of saline. The effects of propentofylline were assessed by observing the body mass gain, behavioural alteration and neurohistological changes. The rats were sacrificed at 72 hours after hypoxia-ischaemia, and the brain sections were examined after haematoxylin and eosin staining. RESULTS: The propentofylline-treated rats had better body mass gain and better behavioural response than the paired saline-controls did. In the control group, the rats either lost body mass or had little mass gain after the insult, their average body mass gain was 97.3% at 24 h, 100.3% at 48 h, and 114.1% at 72 h of recovery. In propentofylline-treated group, there was a significant improvement of body mass gain at 24 h (100.2%, P < 0.05) and 48 h (110.3%, P < 0.01) of recovery; the percentage of rats that performed well on behavioural test was significantly higher from 48 h to 72 h of recovery (P < 0.05); the incidence of severe brain damage to the cerebral cortex and dentate gyrus was significantly reduced in propentofylline-treated rats (cortex, 93% - 70.8%, P < 0.01; dentate gyrus 95% - 66.7%, P < 0.01) as compared with control rats. CONCLUSIONS: Administration of propentofylline 1 hour after hypoxia-ischaemia significantly attenuates brain damage in both the cerebral cortex and dentate gyrus, and also improves the body mass gain as well as behavioural disturbance in 7-day-old rats.