Protective mechanism of demethylase fat mass and obesity-associated protein in energy metabolism disorder of hypoxia-reoxygenation-induced cardiomyocytes.

NEW FINDINGS: What is the central question of this study? What is the effect of fat mass and obesity-associated protein (FTO) on energy metabolism in hypoxia-reoxygenation (H/R)-induced cardiomyocytes? What is the main finding and its importance? FTO modification of N6 -methyladenosine (m6 A) is associated with myocardial cell energy metabolism disorder. FTO reduced the m6 A level of sarcoplasmic/endoplasmic reticulum calcium ATPase 2a (SERCA2a) mRNA through demethylation, thus promoting SERCA2a expression, maintaining calcium homeostasis, and improving energy metabolism of H/R cardiomyocytes. ABSTRACT: Energy metabolism disorder is the initial physiological link of myocardial ischaemia-reperfusion injury. Fat mass and obesity-associated protein (FTO) is an N6 -methyladenosine (m6 A) demethylase implicated in several cardiac defects. This study sought to investigate the effect of FTO on energy metabolism in hypoxia-reoxygenation (H/R)-induced cardiomyocytes. FTO and sarcoplasmic/endoplasmic reticulum calcium ATPase 2a (SERCA2a) expression in H/R-induced cardiomyocytes were determined. Cardiomyocyte viability, cytotoxicity and apoptosis were measured. The total RNA and polyA+ RNA contents were isolated from cells. The m6 A level of RNA and the enrichment of m6 A of SERCA2a mRNA were calculated. Several indices such as the glycolytic potential, reactive oxygen species (ROS), mitochondrial activity and ATP content were evaluated. The concentration of calcium in cardiomyocytes was determined. FTO and SERCA2a were poorly expressed in H/R-induced cardiomyocytes. There was an elevated m6 A level in total RNA and enrichment of m6 A in SERCA2a mRNA. H/R treatment reduced the cell viability, mitochondrial membrane potential and ATP content in cardiomyocytes, but increased the cytotoxicity, apoptosis, ROS content and calcium concentration. Upregulation of FTO reversed the preceding findings with downregulation of the m6 A level of SERCA2a mRNA. Downregulation of SERCA2a annulled the promoting effect of FTO on calcium homeostasis and energy metabolism in H/R-induced cardiomyocytes. Collectively, the current study demonstrated that FTO reduced the m6 A level on SERCA2a mRNA through demethylation, thus promoting SERCA2a expression, maintaining calcium homeostasis and improving the energy metabolism of H/R cardiomyocytes.

Research on the accuracy of dynamic real-time navigation and digital guide navigation implanting techniques / 口腔疾病防治

Objective @#To compare the accuracies of implants with dynamic real-time navigation versus digital guide navigation to provide a reference for clinical precision dental implants. @*Methods@#Forty-six cases (seventy teeth) with missing teeth admitted to the Department of Stomatology, Wuzhou Red Cross Hospital from April 2018 to December 2019 were randomly divided into two groups (thirty-five teeth in each group) for dynamic real-time navigation and digital guide navigation implantation techniques. To compare the entry point, apex point, depth and angle deviation of the preoperative and postoperative position of implants in the two groups. SPSS 21.0 software was used for statistical analysis.@*Results @#Dental implants were successfully placed in both groups. The deviations of apex point, depth and angle in the dynamic real-time navigation group were all smaller than those in the digital guide navigation group, and the differences were statistically significant (P < 0.05). There was no statistically significant deviation in the entry point between the two groups (P > 0.05). @*Conclusion@#In this study, both techniques had good clinical effects. The accuracy of dynamic real-time navigation was higher than that of digital guidance.

[Research advances in the use of digital surgical guides in implantology].

Dental implants have become the main choice for patients to fill in their missing teeth. A precise placement is the basis for a functional and aesthetic restoration. A digital surgical guide is a carrier that transfers the preoperative plan of dental implants to the actual surgery. This paper provides some references that can help clinicians improve the accuracy of implant surgery by stating the development, classification, advantages and disadvantages, and factors that affect the accuracy of digital guides.

[Effect of varying lingual traction forces on the space-closing speed in a typodont model].

OBJECTIVE: To investigate the influences of varying lingual traction forces on the space-closing speed in a typodont model. METHODS: Forty-two Angle Class I standard typodont models of bimaxillary teeth protrusion were divided into 7 equal groups. Four regions of the model were paired to groups, and in the odd-numbered models, the top left and bottom left regions served as the experimental group and the top right and bottom right regions as the control group; in the even-numbered models, the regions in the model were grouped oppositely. In the experimental group, the space was closed by niti wire extension spring in the buccal ridge combined with lingual elastic traction of 0, 5, 10, 15, 20, 25 and 30 g. In the control group, the space was closed by exclusive niti wire extension spring in the buccal ridge. The space-closing speed were analyzed in all the groups. RESULTS: The space-closing speed was significantly lower in the control group than in the experimental groups with lingual traction forces of 5, 10, 15, 20 and 25 g (P<0.05), but a traction force of 30 g resulted in a significantly lower speed than that in the control group (P<0.05). The space closing speed was the greatest in the experimental group with a traction force of 15 g (P<0.05). CONCLUSION: Niti wire extension spring in the buccal ridge combined with lingual elastic traction results in faster space-closing speed than traditional exclusive niti wire extension spring. The speed is the fastest by applying 15 g lingual traction, which is also associated with the lowest slip resistance.

[Clinical observation of improved titanium miniplate internal fixation for mandibular fracture].

PURPOSE: To evaluate the curative effect of titanium compression miniplate internal fixation and craniomaxillary elastic traction in single mandibular fracture. METHODS: 112 patients were treated by two methods respectively: improved titanium miniplate internal fixation and traditional titanium miniplate internal fixation,with 56 cases in each group. The curative effect was evaluated. The data was analyzed with SPSS 10.0 software package for Chi-square test. RESULTS: No infection was found, the mouth opening were over 37mm for 4 weeks after surgery. Titanium compression miniplate internal fixation and craniomaxillary elastic traction was better than traditional titanium miniplate internal fixation in terms of occlusion rehabilitation(P<0.05). No malunion, delayed healing and pseudarthrosis was present in this series. CONCLUSION: Improved titanium miniplate internal fixation is advantageous over traditional titanium miniplate internal fixation with little influence on temporomandibular joint and better occlusion.