Periodontitis is a chronic inflammatory disease that affects the tooth-supporting tissues, and it constitutes a major global public health concern. Methylation modifications, including DNA methylation, histone methylation, and RNA m6A modification, represent reversible processes coordinately regulated by methyltransferases, demethylases, and binding proteins. In periodontitis, aberrant methylation modifications suppress Toll-like receptor 2 expression, leading to oral microbial dysbiosis. These modifications further disrupt normal immune regulatory functions through C-C motif chemokine ligands, Fc-γ receptor-mediated phagocytosis, and NF-κB signaling pathways, resulting in localized immune-inflammatory imbalance in periodontal tissues. In addition, various methylation modifications regulate the expression of Runt-related transcription factor 2 (RUNX2), osteoblast-specific transcription factor Osterix (OSX), and receptor activator of nuclear factor-κB ligand (RANKL), thereby interfering with osteoclast and osteoblast differentiation, disrupting bone homeostasis, and ultimately driving alveolar bone resorption. Methylation-related biomarkers demonstrate promising potential for periodontitis screening and prognostic evaluation. While numerous abnormally methylated sites have been identified in periodontitis, the precise signaling pathways and comprehensive epigenetic regulatory networks remain to be fully elucidated. This review systematically summarizes the functional roles of DNA methylation modifications in the pathogenesis of periodontitis and explores their potential value in etiological studies, diagnostic biomarker discovery, and targeted therapeutic interventions, with the aim of providing novel perspectives for periodontitis prevention and treatment strategies.

Periodontal disease is a common and frequently-occurring disease in China. Early detection, diagnosis, and treatment of periodontal disease are of great significance for achieving universal oral health and even systemic health. Artificial intelligence endows machines with the ability to mimic human intelligent behavior, and is commonly used in medical field with both physical and virtual forms. Virtual artificial intelligence empowers traditional experience in the application of periodontal disease risk assessment and diagnosis, with the potential to develop a variety of oral health screening tools. It helps to provide new evidence for the prognosis of periodontal disease, improve the accuracy and efficiency of diagnosis, reduce technical sensitivity and further promote the periodontal treatment transformation from "treatment-oriented" to "prevention-oriented". This paper reviews the current applications and progresses of virtual artificial intelligence in periodontal risk assessment and diagnosis, as well as its limitations, providing ideas for future researches on the application of virtual artificial intelligence in this field.

Objectives:To explore the effect and possible mechanisms of mild hypothermia on interferon(IFN)-α2b-induced AC16 cardiomyocytes apoptosis. Methods:Cardiomyocytes were stimulated in ordinary temperature and mild hypothermia by IFN-α2b under different concentrations for different times.Proliferation activity of cardiomyocytes was detected by CCK-8 assay.Apoptosis was detected by flow cytometry technique.The effects of different interventions on mitochondrial morphology were examined using Mito-Tracker Green and laser scanning confocal microscope,respectively.The mitochondrial membrane potentials under different intervention conditions were detected by flow cytometry.The fusion of dynamin-related protein 1(Drp1)and mitochondria,and the effects of different interventions on the mitochondria was examined by Drp1 or mitochondrial fluorescent probes and laser scanning confocal microscope.The effects of different intervention conditions on the protein expression level of Phospho-Drp1(p-Drp1)Ser616,Drp1,cleaved poly ADP-ribose polymerase1(cleaved-PARP1),poly ADP-ribose polymerase1(PARP1)were detected by Western blot. Results:CCK-8 assay and flow cytometry results showed that IFN-α2b inhibited the proliferation and enhanced the apoptosis of AC16 cardiomyocytes in a time and dose-dependent manner,these effects could be attenuated by mild hypothermia.Mito-Tracker Green,laser scanning confocal microscope and flow cytometry results showed that the extent of damage of mitochondria with different interventions were attenuated in the setting of mild hypothermia as compared with ordinary temperature.The morphology of mitochondria remained intact and the mitochondrial membrane potentials were the highest in mild hypothermia group.Injured AC16 cardiomyocytes released Drp1 from cytoplasm to mitochondria and increased mitochondrial fission,these effects were abolished after mild hypothermia.p-Drp1 Ser616/Drp1 ratio and cleaved-PARP1/PARP1 ratio were decreased after mild hypothermia,and above effects could be reversed by mitochondrial division inhibitor-1(Mdivi-1)pretreatment. Conclusions:Mild hypothermia inhibits IFN-α2b-induced AC16 cardiomyocytes apoptosis via improving mitochondrial function.

Purpose To establish and evaluate a high-speed fragment-induced penetrating liver injury model in pigs assisted by portable ultrasound.Materials and Methods With the aid of portable ultrasound,the lower edge of the liver at the end of expiration and the lower edge of the right chest at the end of inspiration of 10 Landrace pigs were positioned on the body surface.Then the sighting line was traced to determine the direction of projection and the sighting point.High-speed(about 627 m/s)fragments were projected through an experimental ballistic gun to induce penetrating liver injury.Blood pressure,heart rate,respiratory rate,pulse oxygen saturation and other physiological indexes were measured 15 minutes before shooting and 20 minutes after shooting.20 minutes after injury,the liver injury and the degree of injury were examined by ultrasound.After injury,the liver injury and abdominal fluid accumulation were observed by on-site portable ultrasound,and the size of liver trauma,liver injury grade,abdominal fluid accumulation location and maximum depth were recorded.The degree of liver injury was evaluated by comparison with the gross pathological results.Results Nine out of ten pigs were successfully modeled.The success rate of penetrating liver injury induced by fragments was 90%(9/10),other organ injury in abdominal cavity was 22.22%(2/9),and diaphragm penetrating injury was 22.22%(2/9),which did not occur obvious hemopneumothorax.After injury,the systolic blood pressure,diastolic blood pressure,and pulse oxygen saturation of the pigs decreased[(132.44±12.65)mmHg vs.(103.33±33.43)mmHg,(96.44±12.27)mmHg vs.(70.89±24.21)mmHg,(89.44±8.49)%vs.(76.00±13.41)%;t=2.440,2.651,4.084,all P<0.05],and the heart rate increased[(94.00±17.39)times/min vs.(139.89±37.21)times/min;t=3.534,P<0.05].Within 20 minutes after modeling,portable ultrasound images showed that the liver injury was a patchy,heterogeneous,slightly strong echo area with clear and irregular boundary,and the continuity of the local liver capsule was interrupted.The ascites appeared in the abdominal cavity with the maximum depth of(4.16±1.35)cm.The American association for the surgery of trauma(AAST)liver injury grading of gross pathology after the animals were killed showed that there were 6 cases of grade Ⅱ and 3 cases of grade Ⅲ.Along the fragment projection direction,the short diameter measured by ultrasound was positively correlated with the depth of gross pathological laceration(r=0.945,P<0.001).Compared with the gross specimen,the accuracy rate of ultrasonic AAST grading of liver injury was 88.89%(8/9).Conclusion The model of high-speed fragment-induced liver injury in pigs assisted by portable ultrasound is accurate and stable,and portable ultrasound can effectively evaluate the penetrating liver injury,which provides a basis for the treatment of liver firearm injury.

Objective:To construct a practical education training quality evaluation system that can monitor the entire training process for the master of public health, and to provide a basis for improving the public health education system.Methods:Based on the survey of the current status of the master of public health, combined with the literature survey, the focus group discussion and the expert forum, an evaluation system was established, and the weight coefficient of each index was determined by the analytic hierarchy process (AHP). All data were entered by Excel double-person, and matlabR2018a was used to calculate the weight, and determine the maximum characteristic root of the matrix, consistency index and consistency ratio.Results:The evaluation index system consisted of 7 first-level indicators and 24 second-level indicators. The average authority coefficient of 32 experts was 0.791. The top three items with the highest weight in the first-level indicators were mentor guidance (0.213), professional practice (0.157) and scientific research topics (0.149). The weight coefficient consistency ratio ( CR) was 0.040, showing that the consistency test passed ( CR<0.1). Conclusion:The educational quality evaluation system of the master of public health constructed by the institute is scientific, and the weight of the evaluation index reflects the focus of the postgraduate training process of the master of public health, which can provide a reference for improving the quality of public health professionals.

Objective:To investigate effect of miR-20b on the motor dysfunction after traumatic brain injury (TBI) in mice and the underlying mechanism.Methods:Sixty C57BL/6J mice were divided into sham group, TBI group and TBI+miR-20b Agomir (Agomir-20b) group according to the random number table, with 20 mice per group. A model of severe TBI was induced by controlled cortical impact. After injury, the mice in TBI group were subjected to tail-vein injection of 200 μl Agomir-negative control at dosage of 50 μmol/L and the mice in TBI+Agomir-20b group were subjected to tail-vein injection of 200 μl Agomir-20b at dosage of 50 μmol/L. At days 3 and 7 postinjury, the rate of neuronal apoptosis in the pericontusional region was detected by TUNEL assay, expression levels of apoptosis-related proteins in the pericontusional region were detected by Western blot analysis, including cleaved caspase-3, cleaved poly adenosine diphosphate-ribose polymerases (PARP), B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax), motor function was evaluated by beam walking test, and expression levels of cytokine mRNAs in the pericontusional region were detected by real-time quantitative PCR (RT-qPCR), including interleukin (IL)-1β, IL-6, IL-10, inducible nitric oxide synthase (iNOS), arginase (Arg) and macrophage mannose receptor 1 (CD206).Results:In TUNEL assay, the rate of neuronal apoptosis in sham group was significantly lower than that in TBI group and TBI+Agomir-20b group at days 3 and 7 postinjury (all P<0.01), and there was a significantly lower rate of neuronal apoptosis in TBI+Agomir-20b group as compared with TBI group (all P<0.01). In Western blot analysis, significantly increased levels of cleaved caspase-3, cleaved PARP and Bax proteins and lowered level of Bcl-2 protein were observed in TBI group at days 3 and 7 postinjury as compared with sham group (all P<0.01); similar levels of cleaved caspase-3, cleaved PARP and Bax proteins were found in TBI+Agomir-20b group at days 3 and 7 postinjury as compared with sham group (all P>0.05), and level of Bcl-2 protein in TBI+Agomir-20b group also showed no obvious variation at day 7 postinjury as compared with sham group ( P>0.05) in regardless of a significant reduction at day 3 postinjury ( P<0.01). Significantly increased levels of cleaved caspase-3, cleaved PARP and Bax proteins as well as a significantly reduced level of Bcl-2 protein were found in TBI group at days 3 and 7 postinjury as compared with TBI+Agomir-20b group (all P<0.05 or 0.01). In beam walking test, the latency and foot slip rate in TBI group were significantly higher than those in sham group and TBI+Agomir-20b group at days 3 and 7 postinjury (all P<0.01). In RT-qPCR analysis, levels of IL-1β, IL-6 and iNOS mRNA in TBI group were significantly higher than those in TBI+Agomir-20b group at days 3 and 7 postinjury (all P<0.01), but the two groups were similar in levels of IL-10, Arg and CD206 mRNA (all P>0.05). In comparison with sham group, levels of IL-1β, IL-6, iNOS and IL-10 mRNA in TBI+Agomir-20b group had no obvious change at days 3 and 7 postinjury (all P>0.05); level of Arg mRNA in TBI+Agomir-20b group was significantly increased at days 3 and 7 postinjury (all P<0.01); level of CD206 mRNA in TBI+Agomir-20b group did not change significantly at day 3 postinjury ( P>0.05), but was significantly increased at day 7 postinjury ( P<0.01). Conclusions:miR-20b can obviously inhibit neuronal apoptosis to improve motor function after TBI in mice, for which the underlying mechanism is related to Agomir-20b inhibiting the transformation of microglia to pro-inflammatory M1 type after TBI.

Objective:To investigate the clinical efficacy of ex vivo liver resection and autotransplantation (ELRA) for liver complex space-occupying lesions.Methods:The retrospective and descriptive study was conducted. The clinicopathological data of 50 patients with liver complex space-occupying lesions who underwent ELRA in the First Hospital Affiliated to Army Medical University between June 2009 and May 2017 were collected. There were 36 males and 14 females, aged from 13 to 69 years, with a median age of 51 years. All patients underwent ELRA. Observation indicators: (1) surgical situations; (2) postoperative situations; (3) follow-up. Follow-up was conducted by outpatient examination or telephone interview. Patients were followed up according to the individual follow-up plan in the first 6 months after discharge, and then once every 3 to 6 months to detect tumor recurrence and survival up to May 2019. Measurement data with normal distribution were represented as Mean± SD. Measurement data with skewed distribution were represented as M (range). Count data were expressed as absolute numbers or percentages. The Kaplan-Meier method was used to calculate survival rates and draw survival curves, and Log-rank test was used for survival analysis. Results:(1) Surgical situations: all the 50 patients underwent ELRA successfully, and postoperative pathological examination showed the R 0 resection rate was 100%(50/50). The operation time of the 50 patients were (630±186)minutes, of which 9 patients with liver benign occupation had the operation time of (684±168)minutes and 41 patients with liver malignant tumor had the operation time of (618±190)minutes. The operation time of temporary reconstruction of inferior vena cava and portacaval shunt, time of anhepatic phase, volume of intraoperative blood loss of the 50 patients were (35±9)minutes, (256±71)minutes, 2 000 mL(range, 400-10 000 mL), respectively. The remnant liver mass to standard liver mass ratio of the 50 patients was 65%±16%, of which 9 patients with liver benign occupation had the remnant liver mass to standard liver mass ratio of 63%±14% and 41 patients with liver malignant tumor had the remnant liver mass to standard liver mass ratio of 65%±17%. Of the 50 patients, 35 had vascular invasion (7 cases with liver benign occupation, 28 cases with liver malignant tumor), of which 24 (6 cases with liver benign occupation, 18 cases with liver malignant tumor) underwent in vitro vascular reconstruction, 12 (5 cases with liver benign occupation, 7 cases with liver malignant tumor) had bile duct invasion and underwent choledochojejunostomy due to the inability of the common bile duct to anastomose the ends. Two cases with liver metastasis of gastric cancer, one case with liver metastasis of colon cancer and one case with liver metastasis of pancreatic cancer underwent radical gastrectomy, radical resection of colon cancer, and pancreaticoduodenectomy, respectively. (2) Postoperative situations: the duration of postoperative hospital stay of the 50 patients were 25 days (range, 11-169 days). Of the 50 patients, 12 had pleural effusion who were treated with pleural puncture drainage, 10 had bile leakage who were treated with abdominal puncture drainage, 3 had bile duct anastomotic leakage who were treated with endoscopic nasobiliary drainage or biliary stent implantation, 6 underwent reoperation among which 4 underwent exploratory laparotomy due to abdominal hemorrhage, 1 underwent portal vein reconstruction due to abdominal hemorrhage combined with portal vein thrombosis, and 1 underwent salvage liver transplantation due to liver failure. Nine of the 50 patients died within 90 days after surgery, all of whom had liver malignant tumor. Among them, 3 died of multi-organ dysfunction syndrome caused by severe infection, 3 died of acute liver failure, 2 died of abdominal hemorrhage and 1 died pulmonary embolism. (3) Follow-up: all the 50 patients were followed up for 1 to 119 months. The overall survival time, 1-, 3-, 5-year overall and tumor-free survival rates of the 50 patients after operation were 17 months (range, 1-119 months), 68.0%, 45.9%, 41.1% and 41.9%, 33.4%, 30.8%, respectively. The overall survival time, 1-, 3-, 5-year overall and tumor-free survival rates of the 9 patients who with liver benign occupation after operation were 68 months (range, 10-114 months), 88.9%, 88.9%, 88.9% and 88.9%, 88.9%, 88.9%, respectively. The overall survival time, 1-, 3-, 5-year overall and tumor-free survival rates of the 41 patients who with liver malignant tumor after operation were 15 months (range, 1-119 months), 63.4%, 36.6%, 31.0% and 31.5%, 21.0%, 18.0%, respectively. There were significant differences in the overall and tumor-free survival rates between patients who with liver benign occupation and patients who with liver malignant tumor ( χ2=7.626, 11.766, P<0.05). Conclusions:ELRA can be applied in the treatment of liver complex space-occupying lesions. The selection criteria of patients with liver malignant tumor should be more rigorous to reduce perioperative mortality.

OBJECTIVE：To study the diff erences in the overall chemical constituents of Angelicae dahuricae with and without sulphur-fumigation，and to select chemical markers that can be used for identification. METHODS ：Each 16 batches of A. dahuricae with and without sulphur-fumigation were selected as samples. Deuterated methanol-deuterium oxide （1 ∶ 0.2，V/V）was used as extraction solvent ，and 1H-NMR metabolomics was used to detect the primary and secondary metabolites in A. dahuricae . In addition ，visual analysis ，principal component analysis （PCA）and t-test were used to compare the component differences of A. dahuricae by two kinds of pretreatment methods. RESULTS ：A total of 19 chemical constituents such as coumarins ，amino acids and sugars were simultaneously detected and identified from two kinds of A. dahuricae . Visual analysis showed that the chemical profiles of the two kinds of A. dahuricae were similar ，but their coumarins and carbohydrates were quite different in 1H-NMR signal intensity. PCA analysis showed that all samples could be divided into two categories according to different treatment methods. The results of t-test showed that the contents of oxypeucedanin ，imperatorin，glucose and sucrose of A. dahuricae were decreased significantly after sulphur fumigation （P＜0.01 or P＜0.001），while the contents of alanine and leucine were significantly increased （P＜0.01 or P＜0.001）. There was no statistical significance in the contents of other 13 kinds of components （P＞0.05）. CONCLUSIONS：There are obvious differences in the 6 chemical compounds of oxypeucedanin ，imperatorin，glucose，sucrose， alanine and leucine in A. dahuricae with and without sulphur-fumigation ，which can be used as chemical markers for the identification of sulphur-fumigated A. dahuricae in the market.

Objective:To investigate the acceptance and attitude toward a novel fecal immunochemical test (FIT) in colorectal cancer screening among populations in China.Methods:From May 2018 to May 2019, 2 474 people aged 50-74 years were recruited from five provinces of China (Zhejiang, Anhui, Jiangsu, Hunan and Yunnan). The general demographic characteristics, acceptance of the new FIT technology and operational difficulties through the whole screening process were obtained through questionnaire survey. Multivariate logistic regression model was used to analyze the factors related to difficulties encountered in sampling stool, reading and uploading results.Results:The subjects were (60.0±6.4) years old, and female, high school of above educated, unemployed/retired/other, married and with medical insurance status of “new rural cooperative medical care (NRCMC)” accounted for 61.7% (1 526), 29.0%(718), 34.3% (849), 92.7% (2 293) and 31.3%(775), respectively. The population's acceptance of the FIT technology was 94.8%. In the process of FIT screening, the percentage of occurred difficulties in sampling stool, reading and uploading results were 33.1% (819), 46.4% (1 147) and 62.9% (1 557), respectively. The main difficulties were the uncertainty about whether the sampling operation was standard (28.0%), the inability to accurately judge the result displayed (32.5%) and the need for help without using a smartphone (44.2%). The results of multivariate logistic regression model analysis showed that people aged 65-74 years old and with medical insurance status of “NRCMC” were more likely to encounter difficulties in sampling, and those who were unemployed/retired/other and living with 3 or more family members were less likely to encounter difficulties in sampling. Those aged 65-74 years old, farmers or migrant workers, and those with “NRCMC” were more likely to encounter difficulties in readingresults, and those with 3 or more family members were less likely to encounter difficulties in reading result. Those with “NRCMC” were more likely to encounter difficulties in uploading results, and those with education level of high school or above, living with more than 3 family members were less likely to encounter difficulties in uploading results.Conclusion:The acceptance of the new FIT technology is relatively high among the subjects. Age, education level, occupation, number of family members living together and medical insurance status might be related to difficulties encountered in sampling stool, reading and uploading results, and it can be further strengthened in terms of the technology and characteristics of sub-populations.

Objective:To investigate the acceptance and attitude toward a novel fecal immunochemical test (FIT) in colorectal cancer screening among populations in China.Methods:From May 2018 to May 2019, 2 474 people aged 50-74 years were recruited from five provinces of China (Zhejiang, Anhui, Jiangsu, Hunan and Yunnan). The general demographic characteristics, acceptance of the new FIT technology and operational difficulties through the whole screening process were obtained through questionnaire survey. Multivariate logistic regression model was used to analyze the factors related to difficulties encountered in sampling stool, reading and uploading results.Results:The subjects were (60.0±6.4) years old, and female, high school of above educated, unemployed/retired/other, married and with medical insurance status of “new rural cooperative medical care (NRCMC)” accounted for 61.7% (1 526), 29.0%(718), 34.3% (849), 92.7% (2 293) and 31.3%(775), respectively. The population's acceptance of the FIT technology was 94.8%. In the process of FIT screening, the percentage of occurred difficulties in sampling stool, reading and uploading results were 33.1% (819), 46.4% (1 147) and 62.9% (1 557), respectively. The main difficulties were the uncertainty about whether the sampling operation was standard (28.0%), the inability to accurately judge the result displayed (32.5%) and the need for help without using a smartphone (44.2%). The results of multivariate logistic regression model analysis showed that people aged 65-74 years old and with medical insurance status of “NRCMC” were more likely to encounter difficulties in sampling, and those who were unemployed/retired/other and living with 3 or more family members were less likely to encounter difficulties in sampling. Those aged 65-74 years old, farmers or migrant workers, and those with “NRCMC” were more likely to encounter difficulties in readingresults, and those with 3 or more family members were less likely to encounter difficulties in reading result. Those with “NRCMC” were more likely to encounter difficulties in uploading results, and those with education level of high school or above, living with more than 3 family members were less likely to encounter difficulties in uploading results.Conclusion:The acceptance of the new FIT technology is relatively high among the subjects. Age, education level, occupation, number of family members living together and medical insurance status might be related to difficulties encountered in sampling stool, reading and uploading results, and it can be further strengthened in terms of the technology and characteristics of sub-populations.