Objective: To study the influence of occlusal force changes on apoptosis related gene Bcl-2 and Bax in rat periodontal ligament fibroblasts (PDLF). Furthermore, to explore the possible mechanism in remodeling of periodontal ligaments. Methods: Animal model of occlusal force changes was established by extracting the right first, second and third maxillary molars in male SD rats. Rats were sacrificed at 6,12 hours and 1, 2, 3, 5, 7, 14 and 28 days after teeth extraction(n=6), and their alveolar bone tissues were harvested. HE staining was used to observe the morphologic changes of alveolar bone tissues and immunohistochemistry were used to detect Bcl-2 and Bax expressions in PDLF. The rats of normal occlusal forces were used as control(n=6). The results were assigned a mean score based on the expressions and the intensity of cell positively stained for Bcl-2 and Bax. Results: Animal model of occlusal force changes was successfully established. HE staining showed that the control group had more pycnotic periodontal ligament, orderly aligned fibres, and flatter alveolar bone than model group. Immunohistochemical staining showed that expression of Bax reached its peak at 12 h after extracting the teeth(267.00?7.82), significantly higher than that of control group(25.67?4.97,P

OBJECTIVE To investigate the feas-ibility of preserving parotid duct in regional excision of pleomorphic adenoma. METHODS 32 patients with parotid pleomorphic adenoma were treated by regional excision with the preservation of the parotid duct. RESULTS No relapse occurred during 3-6-year follow-up period. Transient facial nerve palsy occurred in only 3.1%(1/32) of patients and the drainage of the parotid duct on the surgical side was preserved. CONCLUSION Remaining function of the parotid gland function was preserved and the facial nerve was well-protected in the regional excision of pleomorphic adenomas, especially for patients with small pleomorphic adenomas.

Objective To analyze risk factors of northwest dryness syndrome (NDS) among the patients of metabolic syndrome in Xinjiang Uygur Autonomous Region.Methods Totally 321 cases of metabolic syndrome in Kashgar, Hami and Urumqi were collected to filter 15 variables to calculate OR value and 95% CI, and evaluated by single factor and multi-factor analysis by applying conditional Logistic regression analysis.Results Single factor conditional Logistic regression analysis showed that high fat diet, addiction to hot diet, salty diet, smoking history and hypertension were the risk factors of NDS. The OR values of them were 0.387, 0.071, 0.033, 2.614 and 0.440, respectively (P<0.05). Multi-factor conditional Logistic regression analysis showed that smoking history, alcohol drinking history, high fat diet and hypertension were all entered into regression model. The OR values of them were 3.945, 4.334, 0.370 and 2.142, respectively (P<0.01).Conclusion Patients of metabolic syndrome with a high fat, salty and hot diet are suggested to adjust their diet habit by adding sour food, giving up smoking and drinking, and controlling their blood pressure. It will be helpful for them to adapt local climate and living environment, and reduce the attack rate of NDS.

Objective To study the effects of cystic fibrosis transmembrane conductance regulator (CFTR) on neonatal rats with bronchopulmonary dysplasia (BPD).Method The hyperoxia (FiO2＞ 90％)-induced neonatal BPD rat models were established and assigned into three groups:the model group,the agonist group and the antagonist group.Room air (FiO2 21％) was inhaled by the rats in the control group.50 μl of phosphate buffered saline (PBS),genistein (50 mg/kg),arachidonic acid (500 mg/kg) and PBS were injected intraperitoneally respectively in the model group,the agonist group,the antagonist group and the control group at 24,48 and 72 h after birth.The survival rates of the neonatal rats were calculated,the survival curves were drawn,the pathological changes of the lung tissues were examined (the control group and the model group:3,14 and 21 d after birth;the agonist group and antagonist group:14 and 21 d after birth),and the expression of CFTR were studied using western blot method.The acute lung injury scores of the model group,the agonist group and the antagonist group were compared and the gray value was analyzed using Graphpad software.Result (1) The survival rates in the control group,the model group,the agonist group and the antagonist group were 96.8％,93.3％,100％ and 34.5％ respectively.The antagonist group had significantly lower survival rate than the other three groups (P＜0.001).(2)The alveoli developed gradually with age in the control group.The pulmonary pathology of the model group showed:alveolar congestion,hemorrhage,infiltration or aggregation of neutrophils in airspace or vessel wall,thickness of alveolar wall,with some enlarged alveolar spaces and reduced alveolar cavities.As the inflammation gradually decreased,some alveolar spaces significantly enlarged and the numbers of alveolar cavities significantly reduced.No significant differences existed of the acute lung injury scores among the agonist group,the antagonist group and the model group at 14 and 21 d after birth (P＞0.05).(3) The expressions of CFTR in the lungs were lower in the model group than the control group 3 d after birth (P＜0.01).No significant differences existed of the CFTR expression between the model group and the control group 14 d after birth(P＞0.05).The CFTR expression was much higher in the agonist group than the model group (P＜0.01) and also higher in the antagonist group than the model group (P＜0.05) 14 d after birth.The CFTR expression was lower in the model group than the control group,and higher in the agonist group than the model group 21 d after birth (P＜ 0.05).No significant differences existed of CFTR expression between the antagonist group and the model group 21 d after birth (P＞0.05).Conclusion CFTR may play a protective role in the pathogenesis of BPD.

Objective To investigate the effect of rebamipide on chronic non-atrophic gastritis (NAG) with erosion and its protection of gastric mucosa from Helicobacter priori(Hp) associated lesions.Methods Patients(n=452)with endoscopically confirmed NAG with erosion from 11 hospitals in China were enrolled and randomly assigned at a ratio of 3:1 to receive either rebamipide(100 mg t.i.d.)or sucralfate(1.0 t.i.d.)for 8 weeks.Hp infected patients received eradication treatment before randomization.Symptoms,endoscopic scores and histological changes were recorded before and after therapy.Concentrations of serum prostaglandin E(PGE:)and oxygen free radical(MDA)were measured in patients from 2 centers.Results Per-protocol analysis(n=415)showed that the dyspeptic symptom score in rebamipide group decreased significantly after eight weeks of treatment. The endoscopic inflammation score in rebamipide group also decreased from 2.65 ±0.09 to 0.60±0.10(P<0.001),which was,significantly better than that of sucralfate group(P<0.001).Histological findings were consistent with the endoscopic findings.There Was a significant elevation(P=0.002)in PGE2 concentration in mucesa from rebamipide-treated subjects [(225.4±18.3) pg/g vs.(266.7±14.7)Pg/g] compared with that in sucralfate group.The concentration of MDA significantly decreased from(325.9±65.6)mmoL/g to(216.5±61.5)mmol/g,which is markedly different from that of sucralfate group(P=0.046).No statistical difference was found between Hp eradication group,Hp infection group and Hp negative group,regarding the effect of Rebamipide.Conclusion Compared to sucralfate,Rebamipide demonstrates a superior effect on improvement of dyspepsia symptom and endoscopic findings in erosive NAG,which is not influenced by Hp infection.

Objective:To study and design one kind of flash radiotherapy(Flash-RT)equipment with ultra-high dose rate,which can be used in the mechanism research of Flash-RT with ultra-high dose rate.Methods:Based on the technique roadmap of high-power petal accelerator,the Flash-RT equipment can realize the requirement of Flash-RT for ultra-high dose rate and multiple irradiation angles.The corresponding design and research work were carried out on the basis of the overall design of the equipment,the main components and characteristics,the dynamics design of beam,the construction of movable and preliminary experimental platform,etc.Result:The dose rate of the designed equipment can reach to 100 Gy/s at a distance of 0.8 meters from the target point,which is easy to realize the radiotherapy method with multi angles.Conclusion:The designed X-ray equipment based on the technique roadmap of high-power petal accelerator can realize the research for the mechanism of medical Flash-RT equipment with ultra-high dose rate.

The protection effect of flash-radiotherapy(Flash-RT)with super-high dose on normal tissue has obtained wide attention in therapeutic radiology since it was found in 2014 year.The increasing research demand of Flash-RT with super-high dose-rate proposed new challenge for the existing radiotherapy equipment.Based on the demands of FLASH-RT research and clinical application,this review analyzed the proposed new requirement of Flash-RT for equipment,and introduce current scientific facilities with the experimental ability of X-ray FLASH-RT,as well as the situation of the specialized FLASH-RT equipment which were developing.The research of Flash-RT mechanism need the existing equipment with high-energy X-ray source develop toward high power,while the clinical application of Flash-RT demand these transient high-power devices should possess a series of radiotherapy techniques such as multi angle irradiation,conformal radiotherapy and others.Currently,China's X-ray FLASH-RT research is at the forefront of the world,which is expected to achieve the first breakthrough of high-end medical equipment in the X-ray Flash RT field.

Objective:To investigate the risk factors of restenosis after dilation of anastomotic stenosis in patients with esophageal cancer surgery.Methods:Clinical data of 997 patients who underwent endoscopic dilation due to anastomotic stenosis after esophageal cancer radical surgery in the Affiliated Huai′an First Hospital of Nanjing Medical University from June 2015 to July 2021, were retrospectively analyzed. There were 486 cases receiving single dilation (single dilation group) and 511 cases receiving more than two dilations (multiple dilation group). The risk factors of restenosis were explored using univariate and multivariate logistic regression analysis.Results:There were 682 males and 315 females with a median age of 65 years, the median distance between the stenosis and incisor was 20 (20, 22) cm, the median stenosis diameter was 4 (3, 5) mm, and the median stenosis diameter after dilation was 11 (11, 13) mm. Univariate analysis showed that there were significant differences in the distance of the stenosis and incisor ( Z=-2.303, P<0.05), stenosis diameter ( Z=-4.637, P<0.05) and stenosis diameter after dilation ( Z=-5.773, P<0.05) between single and multiple dilation groups. Stratified multivariate logistic regression showed that for male patients, risk of multiple dilations dropped by approximately 3% for every 1-mm increase in the distance between the stenosis and incisor ( OR=0.97, 95% CI:0.93-1.00, P=0.047); the risk of multiple dilations decreased by about 15%, for every 1-mm increase in stenosis diameter ( OR=0.85, 95% CI:0.76-0.94, P=0.004); the risk of multiple dilations decreased by about 13% for every 1-mm increase in stenosis diameter after dilation ( OR=0.87, 95% CI:0.78-0.96, P=0.007). For females patients under 60 years old, the risk of multiple dilations decreased by about 31%, for every 1-mm increase in stenosis diameter after dilation ( OR=0.69, 95% CI:0.47-0.98, P=0.049); for female patients≥60 years old, the risk decreased by about 5%, for every 1-year increase in age ( OR=0.95, 95% CI:0.91-1.00, P=0.037), risk of multiple dilations dropped by 17%( OR=0.83, 95% CI:0.70-0.99, P=0.039) for every 1 mm increase in stenosis diameter after dilation. Stratified smooth curve fitting indicated that the distance between the stenosis and incisor≤23 mm, stenosis diameter≤4.5 mm, stenosis diameter after dilation≤12 mm were risk factors for multiple dilations. Conclusions:The study indicates that patients with the distance between the stenosis and incisor≤23 mm, stenosis diameter≤4.5 mm, stenosis diameter after dilation≤12 mm may need multiple dilations; and the first dilation should expand the stenosis diameter to 12 mm or above as far as possible to reduce the risk of restenosis in patients receiving esophageal cancer radical surgery.

Osteoporotic thoracolumbar fracture in the elderly will seriously reduce their quality of life and life expectancy. For osteoporotic thoracolumbar fracture in the elderly, spinal reconstruction is necessary, which should comprehensively consider factors such as the physical condition, fracture type, clinical characteristics and osteoporosis degree. While there lacks relevant clinical norms or guidelines on selection of spinal reconstruction strategies. In order to standardize the concept of spinal reconstruction for osteoporotic thoracolumbar fracture in the elderly, based on the principles of scientificity, practicality and progressiveness, the authors formulated the Clinical guideline for spinal reconstruction of osteoporotic thoracolumbar fracture in elderly patients ( version 2022), in which suggestions based on evidence of evidence-based medicine were put forward upon 10 important issues related to the fracture classification, non-operative treatment strategies and surgical treatment strategies in spinal reconstruction after osteoporosis thoracolumbar fracture in the elderly, hoping to provide a reference for clinical treatment.

Ankylosing spondylitis (AS) combined with spinal fractures with thoracic and lumbar fracture as the most common type shows characteristics of unstable fracture, high incidence of nerve injury, high mortality and high disability rate. The diagnosis may be missed because it is mostly caused by low-energy injury, when spinal rigidity and osteoporosis have a great impact on the accuracy of imaging examination. At the same time, the treatment choices are controversial, with no relevant specifications. Non-operative treatments can easily lead to bone nonunion, pseudoarthrosis and delayed nerve injury, while surgeries may be failed due to internal fixation failure. At present, there are no evidence-based guidelines for the diagnosis and treatment of AS combined with thoracic and lumbar fracture. In this context, the Spinal Trauma Academic Group of Orthopedics Branch of Chinese Medical Doctor Association organized experts to formulate the Clinical guideline for the diagnosis and treatment of adult ankylosing spondylitis combined with thoracolumbar fracture ( version 2023) by following the principles of evidence-based medicine and systematically review related literatures. Ten recommendations on the diagnosis, imaging evaluation, classification and treatment of AS combined with thoracic and lumbar fracture were put forward, aiming to standardize the clinical diagnosis and treatment of such disorder.