Background/Aims: The accuracy of endosonographers in diagnosing gastric subepithelial lesions (SELs) using endoscopic ultrasonography (EUS) is influenced by experience and subjectivity. Artificial intelligence (AI) has achieved remarkable development in this field. This study aimed to develop an AI-based EUS diagnostic model for the diagnosis of SELs, and evaluated its efficacy with external validation. Methods: We developed the EUS-AI model with ResNeSt50 using EUS images from two hospitals to predict the histopathology of the gastric SELs originating from muscularis propria. The diagnostic performance of the model was also validated using EUS images obtained from four other hospitals. Results: A total of 2,057 images from 367 patients (375 SELs) were chosen to build the models, and 914 images from 106 patients (108 SELs) were chosen for external validation. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the model for differentiating gastrointestinal stromal tumors (GISTs) and non-GISTs in the external validation sets by images were 82.01%, 68.22%, 86.77%, 59.86%, and 78.12%, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy in the external validation set by tumors were 83.75%, 71.43%, 89.33%, 60.61%, and 80.56%, respectively. The EUS-AI model showed better performance (especially specificity) than some endosonographers.The model helped improve the sensitivity, specificity, and accuracy of certain endosonographers. Conclusions We developed an EUS-AI model to classify gastric SELs originating from muscularis propria into GISTs and non-GISTs with good accuracy. The model may help improve the diagnostic performance of endosonographers. Further work is required to develop a multi-modal EUS-AI system.

Objective    To analyze the clinical features and prognosis of coronavirus disease 2019 (COVID-19) patients. Methods    A total of 379 confirmed COVID-19 patients admitted to Public Health Clinical Center of Chengdu from January 16 to November 30, 2020 were divided into two groups including an elderly group (42 patients, ≥60 years) and a non-elderly group (337 patients, <60 years) by age. The epidemiology, clinical features, laboratory tests, treatment and prognosis of the two groups were compared. Results    Among the 379 patients, 286 (75.5%) were males and 93 (24.5%) were females, aged from 2 months to 87 years, with an average age of 41.2 years. The average age of the elderly group was 69.5 years, and 61.9% of them were females. They were imported from Wuhan or local secondary patients (73.8%), mainly common or critical type (88.1%). While, the average age of the non-elderly group was 37.8 years, and males were more common (80.1%). There were mostly from foreign input (75.7%), mainly mild or ordinary type (95.0%). A total of 179 patients (47.2%) had one or more underlying diseases. Hypertension (15 patients, 35.7%) and diabetes (11 patients, 26.2%) were more common in the elderly group, while non-alcoholic steatohepatitis (132 patients, 39.2%) was more frequent in the non-elderly group. The most common clinical manifestations were fever (138 patients, 36.4%) and cough (129 patients, 34.0%). Fever, cough, dyspnea, and fatigue were more common in the elderly group than those in the non-elderly group (P<0.05). Compared with the non-elderly group, the elderly group had lower total lymphocyte count, CD4+ and CD8+ T-cell count, higher level of myocardial injury or inflammation markers (P<0.05). Abnormal echocardiography in 139 patients (36.7%) was mainly caused by decreased left ventricular diastolic function (22.7%) and heart valve regurgitation (14.0%), and the rate in the elderly group was significantly higher than that in the non-elderly group (85.7% vs. 30.6%, P<0.05). After treatment, 3 patients in the elderly group died, and the others were cured and discharged. The hospitalization duration of the elderly group was longer than that of the non-elderly group (22.1 d vs. 18.8 d, P=0.033). Conclusions    Elderly COVID-19 patients are mainly imported from Wuhan or secondary to the local population, mainly common or critical type, often associated with basic diseases such as hypertension or diabetes. While, non-elderly COVID-19 patients are mainly imported from abroad, mainly mild or common type, often associated with non-alcoholic steatohepatitis. After treatment, most of the patients have a good prognosis.

Objective To analyze the application of intraoperative neurophysiological monitoring combined with neuronavigation multi-modal fusion technology in the brainstem glioma resection. Methods One hundred twenty patients with brainstem glioma were divided into observation group and control group. The control group was treated by traditional operation, while the observation group was treated by intraoperative nerve electrophysiological monitoring combined with neuronavigation multimodal fusion technology. The general condition, clinical efficacy, KPS score, complications and survival rate of the two groups were compared. Results The effect was significantly better in the observation group(76.66%)than in control group(53.33%)( x2=11.962,P=0.001).KPS scores were significantly higher in the observation group (27.91 ±1.98) than in the control group (12.11 ±2.13)(t=32.669, P<0.001). Conclusions Intraoperative nerve electrophysiological monitoring plus neuronavigation multimodality fusion technology can improve clinical efficacy and quality of life in patients with brainstem glioma.

Objective To discuss the width of ischiofemoral space (IFS) in asymptomatic adults and the related influence of physiological parameters (including age,sex,height,body weight,intertuberous distance,femoral offset,lesser trochanter height,etc).Methods Pelvic MSCT data of 61 adults without hip pain symptom were analyzed retrospectively.The indexes were measured,including the width of IFS,intertuberous distance,femoral offset,lesser trochanter height,femoral neck long axis,femoral neck angle and ischial angle.The correlation between the width of IFS and the physiological parameters was analyzed.Results The height,body weight,width of IFS,femoral offset,lesser trochanter height and femoral neck long axis of male subjects were larger than those of female subjects (all P＜0.05),while the intertuberous distance and ischial angle of male subjects were smaller than those of female subjects (both P＜0.001).There was positive correlation between the width of IFS and femoral neck long axis (P＜0.001).Negative correlation was found between the width of IFS and the age,intertuberous distance,femoral neck angle,ischial angle,respectively (all P＜0.001).No correlation between IFS and the height,body weight,femoral offset,lesser trochanter height was found (all P＞0.05).Conclusion MSCT can be applied for measurement and evaluation of relative anatomy images of ischiofemoral impingement.The structure of pelvis is different between male and female,and this may be the reason of why female patients are more likely to suffer from ischiofemoral impingement.

Abstract A method for determination of trace mercury in water was established. The trace mercury in water was adsorbed quantitatively by activated carbon, and then determined by electrical pyrolysis atomic absorption spectrometry. In comparison with the detection methods of total mercury in water at present, the method avoids the steps of digestion, reduces the mercury pollution and the loss of the mercury, and is simple in operation. The effects of particle size of activated carbon, acid treatment method, acid medium and enrichment time on the enrichment efficiency were investigated. The effect of the pyrolysis temperature and the interfering ions on the determination results was investigated. Three standard addition procedures including activated carbon blank addition, solution blank addition and environmental water samples addition were studied. Regression correlation coefficients of three standard curves drawn by the three methods reached 0 . 9999 . The slope of the three standard curves had no difference by statistical test, indicating that the determination of mercury in environmental water samples under the experiment conditions was not interfered by the coexistent elements, which showed that the activated carbon blank addition method could be directly used for preparing standard curve of the method. The water samples containing 5 ng/L and 50 ng/L mercury were determined by the method, and the relative standard deviation were 7. 2% and 4. 2% (n=11), respectively, with a detection limit of 1. 2 ng/L. The recovery experiment was carried out after adding 10 ng/L mercury to the surface water and tap water samples, and the recoveries were between 92. 0% and 103. 0%. Analysis results were compared with ICP-MS as control and the deviation of the two methods were between 2 . 9% and 3 . 4%, indicating that the method was accurate and reliable, and had good precision.

Objective To explore the effect of hypoxic preconditioning (HPC) on endoplasmic reticulum stress after traumatic brain injury in rats.Methods Forty-eight Sprague Dawley rats were randomly divided into HPC group (HPC modeling) and non-HPC group (without HPC modeling),with 24 rats in each group.And then,each of the group was further divided into four sub-groups (n=6):three sub-groups after traumatic brain injury (TBI) for one,3 and 7 days (TBI modeling,and drawing and observation after various TBI treatment times),and a control sub-group (without any treatment).HPC models were induced in the low-pressure oxygen chamber for 3 h daily continuing for 3 d.TBI models were established by modified Freeny's freely falling equipment.Modified neurological severity scale (mNSS) scores of the rats were recorded after brain injury.C/EBP homologous protein (CHOP) mRNA and protein expressions were detected by quantitative real-time PCR (qRT-PCR) and Western blotting.TUNEL was used to evaluate the apoptotic rate and the correlation between CHOP levels and apoptotic rate was analyzed.Results The rnNSS scores,relative CHOP mRNA and protein expressions,and apoptotic rate in the one,3 and 7 days subgroups after TBI were significantly higher than those in the control group (P＜0.05);and these levels peaked at 3 d;the mNSS scores,relative CHOP mRNA and protein expressions,and apoptotic rate in HPC group were significantly lower than those in the non-HCP group (P＜0.05);and the correlation analysis showed the CHOP expressions were positively correlated with apoptotic rate in the in HPC group and non-HCP group (r=0.957,P=0.000;r=0.966,P=0.000).Conclusion HPC can down-regulate the expression of pro-apoptotic protein CHOP which participates in endoplasmic reticulum stress pathway,reduce neuronal apoptosis and improve neurological function.

Objective To investigate the association between aortic calcification and risk of vertebral fracture in Chinese postmenopausal women.Methods This study recruited 561 postmenopausal women aged 60 or older who were prospectively followed for 3 years.Based on the ACS,the patients were divided into aortic calcification group (n =236) and non-aortic calcification group (n =325).Extent of aortic calcification and incidence of vertebral fracture were quantified on the baseline lateral radiographs of lumbar spine.Dual energy x-ray absorptiometry was utilized to evaluate the bone mineral density (BMD).Cox proportional hazards models were used to assess the associations between aortic calcification and risk of vertebral fracture.Results In aortic calcification group incidence of vertebral fracture was significantly higher than that in non-aortic calcification group (P ＜ 0.01).Moreover vertebral fracture presented an increased incidence while the ACS was higher.After the adjustment of age,body mass index,BMD,current smoking,current drinking,hypertension,diabetes,total cholesterol,myocardial infarction,stroke and 25-hydroxy vitamin D,aortic calcification with ACS ＞ 6(HR =3.03,95％CI 1.42-6.24),BMD (HR =2.82,95％ CI 1.75-5.68),age (HR =1.96,95％ CI 1.38-4.52),history of two or more falls (HR =1.45,95％ CI 1.24-2.79) and adiponectin (HR =1.07,95％ CI 1.22-2.31) were associated with increased risk of vertebral fracture.Conclusion Severe aortic calcification is closely associated with vertebral fracture for postmenopausal women.

Objective To investigate the effect of hyperbaric oxygen to reduce stress-induced gastric mucosal injury in rabbits with blast-related brain injury.Methods Posttraumatic stress ulcer in a rabbit model of blast-related brain injury was created using paper detonators.Ninety New Zealand white rabbits were randomly divided into normal control group (n =10),blast-related injury group (n =40) and hyperbaric oxygen treatment group (hyperbaric oxygen group,n =40) according to the random number table.Rabbits in blast-related injury group and hyperbaric oxygen group were subgrouped at 6 hours,24 hours,72 hours and 7 days postinjury,with 10 rabbits at each time point.Gastric mucosal injury was detected in aspects of ulcer index,TUNEL method for apoptotic index,and alcian blue-periodic acid-schiff (AB/PAS) staining and semi-quantitative analysis of pathological histology using.Results Neither stress ulcer nor apoptosis occurred in normal control group.At 6 hours,24 hours,72 hours and 7 days postinjury,index of gastric ulcer in blast-related injury group was 12.08 ± 1.02,25.56 ± 0.88,20.36 ±0.96 and 17.56 ± 1.12 respectively,far higher than 8.02 ±0.58,15.22 ± 1.05,12.39 ±0.65 and 9.22 ± 0.79 in hyperbaric oxygen group (P ＜ 0.05) ; apoptotic index in blast-related injury group was 20.22 ± 1.56,27.56 ± 0.96,24.36 ± 1.23 and 16.38 ± 1.24,far higher than 10.78 ± 0.93,13.89 ±0.84,10.55 ± 1.58 and 8.56 ± 1.47 in hyperbaric oxygen group (P ＜ 0.05).Thickness of AB/PAS-positive mucin layers showed marked attenuation even loss in blast-related injury group,but the loss was minor in hyperbaric oxygen group (P ＜ 0.05).Conclusion Hyperbaric oxygen is effective to decrease the stress ulcer index and apoptosis index of gastric mucosa,increase the thickness of AB/PAS positive layer and lighten the gastric mucosal injury of rabbits with blast-related brain injury.

Objective To compare the clinical choosing principles of sedated colonoscopy with con-ventional colonoscopy. Methods Outpatients who were willing to accept colonoscopy with or without seda-tion were prospectively recruited,which were assigned to sedated colonoscopy group(n=362)and conven-tional colonoscopy group(n=323). All patients and endoscopists were asked to answer a self-administered questionnaire. The colonoscopy completion,operation time,procedure-related discomfort,and questionnaire results of the two groups were compared and statistically analyzed. Results The completion rate was 98. 9%in the sedated colonoscopy group(358/362)and 89. 8% in the conventional colonoscopy group(290/323) ( P=0. 337 ). The operation time of sedated and conventional group were( 5. 60 ± 3. 25 ) minutes and (7. 71 ± 5. 70)minutes respectively(P<0. 001). And the average cost was CNY 886. 54 per patient in se-dated group and CNY 386. 00 per patient in the conventional group. Patient satisfaction score of conventional group and sedated group were 4(3-4)and 3(2-3)points(P<0. 001),while endoscopist satisfaction score was 4(3-4)and 4(4-4)(P<0. 001). A total of 354 patients(97. 79%)in the sedated group and 225 pa-tients(69. 66%)in the conventional group showed willingness to repeat the identical colonoscopy( P <0. 001). Patients who were male(P=0. 035),having no past abdominal operations(P<0. 001),or no ab-dominal pain during colonoscopy( P =0. 015 )in the conventional group preferred to repeat conventional colonoscopy. Conclusion Although the examination time of conventional colonoscopy is longer than sedated colonoscopy,it could reduce anesthesia risk and the cost. Conventional colonoscopy remains an irreplaceable examination of colorectal diseases in developing countries. Physicians should not only focus on patients'com-fort during endoscopy,but also help patients make a decision based on their actual situation and endoscopic indications to make the best of medical resources.

Objective To research the influence of hypoxic preconditioning in anti-oxidative ability of brain tissues and neurological functions in rats after traumatic brain injury.Methods Forty eight adult male Sprague Dawley rats were randomly divided into sham-operated group,hypoxic preconditioning group (HPC),traumatic brain injury group (TBI) and hypoxic preconditioning+traumatic brain injury group (HPCT,n=12).The HPC rat models were made by hypobaric chamber for 3 d (50 kPa,3 h/d) and TBI were induced by Feeney's improved equipment.All rats were killed 24 h after injury,and the neurological functions of each group were evaluated by modified neurologieal severity scale (mNSS);the neuronal survival around contusion area was detected by NeuN immunohistochemical staining,and the protein and mRNA expressions of nuclear transcription factor-related factor 2 (Nrf2) and thioredoxin reductases 2 (TrxR2) in the brain tissues were detected by Western blotting and real-time quantitative PCR.Results The mNSS scores in the TBI and HPCT groups were significantly higher as compared with those in the sham-operated and HPC groups (P＜0.05),but those in the HPCT group was significantly lower than those in the TBI group (P＜0.05).The neuronal survival in the TBI and HPCT groups was decreased as compared with that in the sham-operated and HPC groups (NeuN expressions:0.274±0.033,0.281±0.042 vs 0.124±0.014,0.150±0.019),with significant difference (P＜0.05),while that in the HPCT group was statistically increased as compared with that in the TBI group (P＜0.05).The expressions of Nrf2 and TrxR2 in the brain tissues of TBI and HPCT groups were significantly increased as compared with those in the sham-operated and HPC groups (P＜0.05),and those in the HPCT group was significantly up-regulated as compared with those in the TBI group (P＜0.05).Conclusion HPC can increase the anti-oxidative ability and relieve the neurological functions missing after TBI.