Objective:To characterize the severe sports injuries related to alpine skiing during the 2022 Beijing Winter Olympics and Paralympics so as to provide information for the prevention and treatment of sports injuries in the Yanqing National Alpine Skiing Center tracks.Methods:The medical data were collected of all the alpine skiing athletes and related staff who had sought medical treatment in Peking University Third Hospital Yanqing Hospital during January 20, 2022 to March 26, 2022. Descriptive statistical analyses were conducted for body part, type, occurrence place, and severity of the injuries.Results:There were 49 patients who had suffered severe injuries related to alpine skiing events during this Olympic Games, with 68 injuries by body parts and 72 injuries by types. The most common injury part was the knee (25.0%, 17/68), followed by the head (14.7%, 10/68), and the shoulder (8.8%, 6/68). The most common types of injury were contusion (including hematoma and abrasion, 30.6%, 22/72), followed by sprain (including dislocation, subluxation, and ligament injury, 22.2%, 16/72), and fracture (20.8%, 15/72). The most common occurrence place in the tracks for athletes was the "Haituo Bowl" area (41.7%, 10/24). In terms of severity, the injuries led to an absence from training or competition in 48 athletes [98.0% (48/49)], of whom 33 were severely injured [67.3% (33/49)].Conclusions:The most vulnerable part for severe sports injuries in the alpine skiing events of the 2022 Beijing Winter Olympics and Paralympics was the knee, mostly with ligament injuries, which is consistent with the findings of previous events. The high proportion of severe injuries indicated the difficulty of this track. The place where injuries mostly occurred was the "Haituo Bowl" area of the racing track, also the most challenging part of this track, indicating a necessity of more medical resources in this area.

Objective To investigate the role of nitric oxide synthase(NOS)in the regulation of myocardial ischemia-reperfusion(IR)injury in ovariectomized(OVX)rats.Methods A total of 132 female SD rats were subjected,and 48 of them were randomly divided into sham operation group,IR group,OVX group and combined group,with 12 in each group.In order to explore the role of endothelous NOS(eNOS)and inducible NOS(iNOS)in ovariectomization increasing myo-cardial IR injury,another 84 mice were divided into negative sham group,negative IR group,nega-tive combined group,eNOS+IR group,eNOS combined group,iNOS small interfering RNA(si-iNOS)+IR group and si-iNOS combined group,with 12 in each group.The mice of the corre-sponding groups were injected with adeno-associated virus(AAV)overexpressing eNOS or knoc-king down iNOS via tail vein before OVX modeling.Myocardial infarct size,serum levels of lac-tate dehydrogenase(LDH)and creatine phosphokinase isoenzyme(CK-MB),LVEF,LVFS,and expression levels of eNOS and iNOS in the myocardial tissues were measured.Results The com-bined group had significantly increased level of iNOS in myocardium,larger myocardial infarct size and elevated serum LDH and CK-MB levels,but decreased myocardial expression of eNOS and LVEF and LVFS values than the IR group(P＜0.05).When compared with the negative combined group,the myocardial infarct size and serum LDH and CK-MB levels were decreased[(23.51±3.22)％and(26.21±2.93)％vs(58.78±5.42)％,(176.31±15.48 and 169.52±17.12 vs 328.85±37.12 U/L,35.41±6.41 and 34.77±5.94 vs 88.73±9.14 U/L,P＜0.05],and the LVEF and LVFS values were increased[(41.31±3.12)％and(42.09±3.41)％vs(30.77± 2.15)％,(21.47±1.57)％and(21.32±1.42)％vs(15.92±1.33)％,P＜0.05]in the eNOS com-bined group and si-iNOS combined group.Conclusion The decrease of eNOS expression and in-crease of iNOS expression are related to the aggravation of myocardial IR injury in OVX rats.

Objective:To observe and analyze the correlation between macular microvascular parameters and urinary albumin to creatinine ratio (UACR) in patients with type 2 diabetes mellitus (T2DM).Methods:A cross-sectional study. From October 2017 to April 2018, 100 eyes of 100 patients (T2DM) and 27 eyes of 27 healthy controls (the control group) were enrolled in Xuzhou First People’s Hospital. All subjects underwent anterior segment examination via slit-lamp biomicroscopy, dilated fundus examination, 7-field fundus photographs, OCT angiography (OCTA), the fasting glucose test, glycosylated hemoglobin (HbA1c), urinary albumin, urinary creatinine and UACR levels determination. Height and weight measurement were taken for calculating body mass index (BMI). Diabetic retinopathy was ruled out by fundoscopic examinations and 7-field fundus photographs in T2DM patients. According to the UACR, patients in the T2DM group were subdivided into A1 group (UACR< 30 mg/g), A2 group (UACR 30-300 mg/g), and A3 group (UACR>300 mg/g), with 38 cases and 38 eyes respectively , 40 cases with 40 eyes, 22 cases with 22 eyes. A 6 mm×6 mm scanning area centered on the macular fovea were scanned for right eye using a frequency domain OCTA instrument, which were divided into three concentric circles centered on the macular fovea by the software automatically. The foveal zone was defined as a circular area measuring 1 mm in diameter, the parafoveal zone was described as a middle circle area measuring 1-3 mm in diameter, and the perifoveal zone was an outer circle area measuring 3-6 mm in diameter. The vessel density of superficial capillary plexus (SCP) and deep capillary plexus (DCP), foveal avascular area (FAZ) and perimeter (PERIM), non-circularity index (AI) were measured. The correlation between the macular vessel density, FAZ and UACR was analyzed by Spearman correlation analysis.Results:A1 group, A2 group, A3 group, and normal control group. The macular area SCP and DCP ( F=13.722, 5.644), foveal area ( F=4.607, 4.719), parafoveal area ( H=23.142, F=2.904), the blood flow density of the area around the fovea ( F=12.292, H=10.946), the difference was statistically significant ( P<0.05); with the increase of UACR, the blood flow density of each area of SCP and DCP showed a downward trend. The results of correlation analysis showed that the blood flow density of the whole SCP, parafoveal area, and surrounding area of T2DM patients was negatively correlated with UACR ( r=-0.376, -0.240, -0.364,-0.347, P<0.05). There were no correlation among fasting plasma glucose, HbAlc and UACR ( r=0.179, 0.085, P>0.05). There were no correlation among blood flow density in BMI, SCP foveal area, DCP and UACR (| r|<0.3, P>0.05). Conclusion:The whole, parafovea and perifovea vessel density values of SCP in T2DM eyes without DR are negatively correlated with UACR.

Objective To investigate the occurrence and characteristics of dysphagia and aspiration in the elderly in nursing home in Weifang, Shandong, China.Methods From January to June, 2021, 837 elderly people from 10 nursing homes in Weifang were randomly selected and investigated with general situation questionnaire, Fried Frailty Phenotype, Ohkuma questionnaire and Volume-Viscosity Swallowing Test.Results The prevalence of dysphagia and aspiration was 44.2% and 12.3% respectively. There were significant differences in the prevalence of dysphagia among ages and health condition (χ2 > 8.437, P<0.05). The prevalence of dysphagia and aspiration was higher in men than in women (χ2 > 4.060, P < 0.05). The incidence of oral dysphagia was higher in men than in women, and the incidence of esophageal dysphagia was lower (χ2 > 20.830, P<0.001). Oral dysphagia was predominant in the elderly with stroke, Alzheimer's disease, and Parkinson's disease (χ2=27.579, P<0.001), and esophageal dysphagia and airway protection dysfunction were predominant in the elderly with chronic respiratory disease (χ2 > 20.241, P<0.01).Conclusion The dysphagia and aspiration are prevalent in the elderly in nursing homes, and varies with different genders and basic diseases.

Spinal cord injury (SCI) is a disabling and destructive central nervous system injury that has not yet been successfully treated at this stage. Three-dimensional (3D) bioprinting has become a promising method to produce more biologically complex microstructures, which fabricate living neural constructs with anatomically accurate complex geometries and spatial distributions of neural stem cells, and this is critical in the treatment of SCI. With the development of 3D printing technology and the deepening of research, neural tissue engineering research using different printing methods, bio-inks, and cells to repair SCI has achieved certain results. Although satisfactory results have not yet been achieved, they have provided novel ideas for the clinical treatment of SCI. Considering the potential impact of 3D bioprinting technology on neural studies, this review focuses on 3D bioprinting methods widely used in SCI neural tissue engineering, and the latest technological applications of bioprinting of nerve tissues for the repair of SCI are discussed. In addition to introducing the recent progress, this work also describes the existing limitations and highlights emerging possibilities and future prospects in this field.

Objective:To study the effect of rotational errors on the positioning accuracy (PA) and to assess whether correcting rotation in patients with head-neck tumors in radiotherapy or not.Methods:The image information of 34 patients with head-neck tumors treated at Zhongnan Hospital of Wuhan University between August 2019 and January 2020 was collected. Mega-voltage computed tomography (MVCT) images of each patient were taken before radiotherapy, and were registered with planned kilo-voltage computed tomography (KVCT) images by two registration methods. All information was divided into control group (translation only) and intervention group (translation and rotation) according to different registration methods, there were 144 fractioned registered images for each group, respectively. The position errors of the two registration methods were recorded and compared. Data were carried out with Wilcoxon signed rank test and Spearman rank correlation.Results:Translational errors of the control group and the intervention group were 0.10 (5.35) mm and 0.00 (5.78) mm in right-left direction, and there was a statistically significant difference ( Z=-2.675, P=0.007); 0.75 (2.78) mm and 0.60 (2.68) mm in superior-inferior direction, and there was a statistically significant difference ( Z=-2.819, P=0.005); 0.10 (0.90) mm and 0.20 (1.28) mm in anterio-posterior direction, and there was a statistically significant difference ( Z=-3.984, P<0.001). Rotational errors of the intervention group were -0.20 (0.60)°, 0.35 (2.00)°, 0.00 (0.98)° in pitch, roll, yaw, respectively. The distribute of 3D vector corrected frequency for two groups was positively skewed. The corrected cumulative frequency (CCF) varied with 3D vector, 3D vector was 8.0 mm, and 19 F and 16 F fractioned treatments of the control group and the intervention group were not corrected, respectively; 3D vector was between 8.0-13.5 mm, the corrected tendency of the intervention group was slower and fractioned treatment was completed later. The analytical results of Spearman rank correlation showed that rotational errors in pitch were negatively correlated with translational errors of the control group in superior-inferior direction ( r=-0.182, P=0.029) and the intervention group in anterio-osterior direction ( r=-0.484, P<0.001); rotational errors in roll were negatively correlated with translational errors of the intervention group in right-left direction ( r=-0.334, P<0.001); rotational errors in yaw which were positively correlated with translational errors of the intervention group in right-left direction ( r=0.370, P<0.001) were negatively correlated with translational errors of the control group in superior-inferior direction ( r=-0.171, P=0.040) and the same was true for the intervention group ( r=-0.203, P=0.015); total angles were positively correlated and negatively correlated with translational errors of the control group in superior-inferior direction ( r=0.246, P=0.003) and anterio-posterior direction ( r=-0.188, P=0.024), and positively correlated with 3D vector of the control group ( r=0.198, P=0.017), total angles were positively correlated with translational errors of the intervention group in superior-inferior direction ( r=0.170, P=0.041) and with 3D vector of the intervention group ( r=0.239, P=0.004); there were no correlations between rotational errors and the other translational errors (all P>0.05). Conclusion:Although the corrected rotation increases translational errors in anterio-posterior direction and 3D vector, it improves PA for head-neck tumors in radiotherapy. When rotational errors are not corrected, rotational offsets are present with corrected translation to decrease its effect on PA.

Objective:To introduce the standard screw implantation methods and to analyze the biomechanical stability of the second-generation dynamic anterior plate-screw system for quadrilateral area (DAPSQ).Methods:Six adult formalin-preserved corpses were selected to make a complete pelvic specimen. Further, the left high double-column fracture models were made and randomly fixed with second-generation DAPSQ or anterior reconstruction titanium plate and 1/3 tube buttress-plate (ARTPB). The specimens of intact pelvis (IP) group, DAPSQ group and ARTPB group were fixed on a Zwick Z100 material machine and loaded vertically with 200 N, 300 N, 400 N, 500 N, 600 N, 700 N, and 800 N in a simulated sitting position, respectively. The axial displacement and strain changes in the anterior and posterior columns were tested in the three groups. The stiffness was calculated accordingly.Results:The axial compression displacement in the three groups showed an increase trend as well with the vertical load increased from 200 N to 800 N ( F=68.581, P<0.001; F=91.795, P<0.001; F=33.819, P=0.002). The axial displacement in ARTPB group was significantly larger than that in DAPSQ group and IP group ( P<0.05), while the difference between DAPSQ and IP groups was not significant ( P>0.05). Under the vertical load of 600 N, the pelvic axial stiffness of IP group, DAPSQ group, and ARTPB group were 220.72±70.33 N/mm, 185.68±48.49 N/mm and 135.83±60.58 N/mm, respectively. The axial stiffness of ARTPB group was significantly lower than that in DAPSQ group and IP group ( t=5.345, P=0.003; t=6.443, P=0.001), while the difference between DAPSQ and IP groups was not significant ( t=2.138, P=0.086). There were no significant differences of the strain values in anterior column among the three groups during the load increasing from 200 N to 800 N ( P>0.05). With the load increasing from 500 N to 800 N, the strain values of the posterior column in ARTPB group were significantly greater than those of IP and DAPSQ groups ( P<0.05). However, the differences between IP and DAPSQ groups were not statistically significant in strain values of the posterior column ( P>0.05). Conclusion:Compared with anterior reconstruction titanium plate and 1/3 tube buttress-plate, acetabular double-column fracture model fixed with the second-generation DAPSQ has less axial compression displacement but with greater axial stiffness. The stress change in the posterior columns of the acetabulum is like in IP. Therefore, the second-generation DAPSQ has reliable biomechanical stability.

Objective:To investigate the clinical safety and efficacy of tirofiban in the treatment of hemiplegic stroke warning syndrome.Methods:Patients with hemiplegic stroke warning syndrome admitted to Jining First People's Hospital without receiving intravenous thrombolysis from January 2018 to May 2020 were enrolled retrospectively. Some patients were given tirofiban intravenous infusion for at least 24 h in acute phase, then received oral antiplatelet therapy (tirofiban group); some only received aspirin+ clopidogrel dual antiplatelet therapy (control group). The primary endpoint was muscle strength at the paralytic side and National Institutes of Health Stroke Scale (NIHSS) score at day 7 after onset. The secondary endpoint was the modified Rankin Scale (mRS) score at 3 months after onset, and ≤2 was defined as good clinical outcome. The safety endpoint was the bleeding events during treatment. Multivariate logistic regression analysis was used to determine the independent influencing factors of clinical outcome. Results:A total of 30 patients with hemiplegic stroke warning syndrome were enrolled, including 19 (63.3%) in the tirofiban group and 11 (36.7%) in the control group. There was no significant difference in baseline clinical data between the two groups, and no drug-related bleeding complications occurred during treatment. The muscle strength at paralytic side and NIHSS score at day 7 after onset, NIHSS score at discharge and good clinical outcome rate at 3 months in the tirofiban group were significantly better than those in the control group, and the differences were statistically significant (all P<0.05). Multivariate logistic regression analysis showed that tirofiban was an independent protective factor for good outcome after adjusting the NIHSS score at the beginning of treatment (odds ratio 0.040, 95% confidence interval 0.040-0.449; P=0.009). Conclusions:Tirofiban is safe and effective in the treatment of patients with hemiplegic stroke warning syndrome in acute phase. It can effectively block the progress of the disease, improve the outcome of patients, and will not increase the risk of bleeding.

Gallbladder-duodenal fistula is a rare disease in clinical practice, and difficult to diagnosis. One patient with high suspicion of gallbladder-duodenal fistula in preoperative examination was performed with percutaneous transhepatic gallbladder drainage due to could not tolerate surgical operation, and gallbladder-duodenal fistula was diagnosed with the gastric and intestinal fluids extracted from the drainage tube. In the later of fistula repair and the patient′s nutritional support management, the jejunal nutrition tube is inserted through the bile duct, and then the nutrition support was performed through this jejunal nutrition tube. This patients was recovered well.

Objective:To investigate the current Kangaroo Mother Care(KMC) knowledge among registered nurses working in neonatal intensive care unit (NICU) in China.Methods:A convenience sample of 607 registered nurses participated in this descriptive, cross sectional exploratory study. An online self-designed questionnaire was used to collect the data, including 12 items, 3 sections (Basic knowledge, Emergency handling, Breast feeding).Results:The total score was 6.52±2.29 (the total score was 12). The 5 items, accuracy below 50%, were ①In your opinion, the optimal duration of KMC was (10.2%,62/607); ②What to do if the baby had respiratory arrest or became blue during KMC (18.8%,114/607); ③Who should implement KMC (42.5%, 258/607); ④what could we do if the baby was not gaining weight (47.3%, 287/607); ⑤How to feed the baby during KMC (47.8%, 290/607). Registered nurses with more than 10 years of working experience in NICU scored higher; junior registered nurses scored lower; registered nurses learned by individuals scored lower ( F values were 9.413, 9.862, 5.368, all P<0.01). Conclusions:The insufficiency of KMC knowledge is common among NICU registered nurses. The understanding of basic concepts of KMC should be strengthened. Stratified training should be conducted for nurses′ ability to deal with emergencies, assess the changes in infants' conditions, and knowledge of breast feeding. All registered nurses′ KMC operation should be standardized to improve the level of implementation of KMC by NICU registered nurses.