Objective With the development of manned space missions to the moon and space exploration,extravehicular activities become more frequent and extravehicular mission become more complex,which puts forward higher requirements for the extravehicular spacesuit.In order to ensure the ergonomics of spacesuit,the flexible joints are usually adopted in the limbs of spacesuit.The structural design of large angle of movement and low resistance joints is the basic for ensuring the ergonomics of spacesuit.Methods This study established a method of spacesuit joint structure to analysis the motion characteristic of typical joints.Firstly,the structure and activity characteristics of the spacesuit and lunar space suits were comprehensively analyzed,and the activity characteristics of different typical structure are qualitatively analyzed based on existing empirical method.Then,the dynamics of typical structure was analyzed by finite element model.By studying the change trend of motion of spacesuit joint with motion angle,and the motion characteristic curve was obtained.Finally,the model was studied according to different structural size parameters.The influence of structural parameters on the motion characteristics was analyzed,and the curves was obtained to provide a basis for design of spacesuit motion joint structure.Results Through the above analysis,the motion characteristics of different typical structure are obtained qualitatively.And the influence of different structure parameters on the motion characteristics was analyzed.This establishes the method basis for structure design.Conclusion The study was carried out a method based on finite element model for joint motion analysis,which is suitable for the design of typical joint structure of spacesuit.

Objective:To investigate the clinical and endoscopic characteristics of patients with autoimmune gastritis (AIG).Methods:From January 1, 2013 to December 31, 2023, 73 AIG patients who visited Peking Union Medical College Hospital were retrospectively enrolled. The clinical data of all the patients were analyzed, including gender, age, symptoms, laboratory examination results (such as serum hemoglobin, vitamin B 12, serum iron, gastrin, anti-parietal cell antibody (APCA), anti-intrinsic factor antibody (AIFA), Helicobacter pylori ( HP) infection status; the indicators were judged based on the normal reference value), and endoscopic and histopathological examination results. Descriptive statistical methods were used for statistical analysis. Results:Among the 73 AIG patients, there were 27 males (37.0%) and 46 females (63.0%), with a median age of 57 years old (ranged from 25 to 85 years old). Among the 73 AIG patients, 68 patients received APCA test, with a positivity rate of 88.2% (60/68); 67 patients took the AIFA test, with a positivity rate of 52.2%(35/67); 62 patients underwent both APCA and AIFA tests, of which 22 patients (35.5%) showed double positive. Serum level of vitamin B 12 was detected in 59 patients, and decreased in 27 cases (median level: 0.100 ng/L, mean level: 0.102 ng/L). Gastrin level was detected in 58 patients, and increased in 55 cases (median level: 0.930 ng/L, mean level: 1.203 ng/L). The levels of serum iron and ferritin were tested in 52 patients, the level of serum iron of 5 cases decreased, and the level of ferritin of 17 cases decreased (median level: 780.0 and 26.0 μg/L, mean level: 807.8 and 76.0 ng/L, respectively).Among the 73 AIG patients, the urea breath test was performed in 12 patients, and the result was positive in 6 cases. Endoscopic rapid urease test was performed in 69 patients, and the result was positive in 11 cases (15.9%). Regular blood analysis was performed in 71 patients, 24 cases (33.8%) were diagnosed with anemia, the median age of patients with anemia was 55 years old, and male-to-female ratio was 1∶5. There were 6 cases of iron-deficiency anemia and 5 cases of pernicious anemia. The endoscopic examination results of 73 patients indicated that 65 cases (89.0%) with mucosal atrophy under endoscopy, including 47 cases (64.4%) with mucosal atrophy in the gastric fundus and body, and 18 cases (24.7%) with whole gastric atrophy, more obviously in the gastric body. The pathological examination results showed type Ⅰ gastric neuroendocrine tumor(g-NET) in 35 cases (47.9%). Conclusions:The early clinical symptoms of AIG patients are nonspecific, often present with anemia and vitamin B 12 deficiency. Close monitoring of serological markers including APCA, AIFA and gastrin is essential. For patients diagnosed or suspected with AIG, intervals of endoscopic surveillance should be shortened to prevent the genesis and development of neoplasms such as g-NET.

Objective:To identify the risk factors for acute graft-versus-host disease (aGVHD) in patients with acute myeloid leukemia (AML) undergoing haploidentical hematopoietic stem cell transplantation (HID-HSCT) .Methods:A total of 141 AML patients who underwent HID-HSCT at the Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences, from January 2020 to July 2021 were included. The cumulative incidence of aGVHD was analyzed using the Fine-Gray competing risk model, with relapse and death as competing events, to compare differences between groups. Potential risk factors were evaluated by univariable and multivariable Cox proportional hazards regression analyses to determine their independent effects on aGVHD.Results:Among the 141 patients, 86 (61.0%) were male and 55 (39.0%) were female, with a median age at transplantation of 34 years. Within 100 days post-transplant, 59 patients developed grade Ⅱ-Ⅳ aGVHD, whereas 86 patients experienced no or grade Ⅰ aGVHD (the grade 0-Ⅰ aGVHD group) . Survival analysis showed that the 3-year overall survival was 68.7% (95% CI: 57.7%-81.9%) in the grade Ⅱ-Ⅳ aGVHD group, compared with 78.8% (95% CI: 70.4%-88.3%) in the grade 0 - Ⅰ aGVHD group, with the difference not being statistically significant ( P=0.190) . Univariable analysis identified donor age ( P=0.020, HR=1.020, 95% CI: 1.000-1.040) and the female donor-male recipient sex combination ( P=0.033, HR=1.980, 95% CI: 1.160-3.380) as risk factors for grade Ⅱ-Ⅳ aGVHD. Multivariable analysis confirmed that donor age ( P=0.005, HR=1.026, 95% CI: 1.008-1.047) and the female donor-male recipient sex combination ( P=0.002, HR=2.339, 95% CI: 1.354-4.037) were independent risk factors for aGVHD. Patients receiving grafts from donors aged >45 years had a significantly higher 100-day cumulative incidence of grade Ⅱ-Ⅳ aGVHD compared with those receiving grafts from donors ≤45 years [54.7% (95% CI: 42.3%-67.0%) vs 31.6% (95% CI: 21.0%-42.1%) , P=0.006]. Similarly, patients with the female donor-male recipient sex combination had a higher 100-day cumulative incidence of grade Ⅱ-Ⅳ aGVHD than those with other sex combinations [56.8% (95% CI: 40.4%-73.1%) vs 36.9% (95% CI: 27.5%-46.3%) , P=0.015]. Conclusion:Older donor age and the female donor-male recipient sex combination remain independent risk factors for aGVHD in patients with AML undergoing HID-HSCT.

Objective:To analyze the real-world practices of resecting sessile colorectal polyps of varying long diameters using cold forcep polypectomy (CFP), cold snare polypectomy (CSP), or endoscopic mucosal resection (EMR).Methods:A total of 12 290 nonpedunculated colorectal polyps of long diameter ≤19 mm (from 10 295 patients) were retrospectively enrolled from January 2022 to December 2023. Polypectomy was conducted by 30 endoscopists. The polyps were categorized into three groups based on long diameter: 1-5 mm, >5-10 mm and >10-19 mm, and the differences of polypectomy methods were compared in three groups. The usage of hemostatic clips in CSP among >5-10 mm polyps and the changes in resection methods between 2022 and 2023 were analyzed.Results:CFP (6 769 polyps, 81.7%) was the predominant method for resecting 1-5 mm sessile polyps (8 289 polyps). For sessile polyps sized >5-10 mm (2 455 polyps), CSP was used most (1 372, 55.9%), although its utilization varied significantly among physicians with the median usage rate of 52.9% (40.3%, 60.0%). EMR (1 349 poolyps, 87.3%) was the main method for >10-19 mm sessile polyps. The usage rate of CSP in sessile polypectomy for polyps >5-10 mm significantly increased from 45.7% (503/1 101) in 2022 to 64.2% (869/1 354) in 2023. The overall frequency of using clip in CSP for >5-10 mm sessile polyps was 40.1% (550/1 372), demonstrating notable variability among different endoscopists with median usage rate of 48.3% (29.8%, 67.9%).Conclusion:Varied resection methods are observed among endoscopists for sessile polyps measuring ≤19 mm. CFP is primarily utilized for polyps of 1-5 mm, while CSP is favored for polyps >5-10 mm, with an increasing annual usage rate. EMR is the main approach for the polyps >10-19 mm. Additionally, notable variations in the use of metal clips during CSP are observed among different physicians.

Objective To explore the methods of continuing education for advanced endoscope operations by diges-tive specialists through the establishment and teaching effect evaluation of the ERCP(endoscope retrograde cholan-giopancreatography)introductory training mode.Methods A total of 26 trainees from 3 sessions of the ERCP intro-ductory training courses at Peking Union Medical College Hospital from September 2023 to September 2024 were in-cluded.The teaching effects of the training courses and its 5 modules were subjectively and objectively evaluated by questionnaires,on-site tests and evaluations by senior ERCP operators.Results Through the ERCP introductory training courses,the trainees'self-evaluated proficiency in duodenoscope structure(pre-training:2.4±2.4,post-training:8.2±1.5,P＜0.001),duodenoscope operation(pre-training:1.2±2.2,post-training:6.6±1.8,P＜0.001),papillary cannulation(pre-training:0.5±1.3,post-training:5.4±1.8,P＜0.001),intra-bile duct operation(pre-training:0.2±0.6,post-training:4.9±2.1,P＜0.001),and identification of intra-bile duct lesions(pre-training:1.7±2.1,post-training:6.0±2.0,P＜0.001)was significantly improved.The accuracy rate of the trainees'theoretical tests and picture recognition before training was 37.2％and then increased up to 62.8％after training.Before training,all trainees were considered by senior operators as not ready to start ERCP training on real patients,while after training,69.2％(18/26)of the trainees were considered ready to start ERCP training on real patients.Conclusions The multi-module ERCP introductory training courses have a significant effect in terms of laying a foundation for trainees to start ERCP training on patients and of providing a reference for the con-tinuing education mode of advanced endoscope operations for digestive specialists in China.

Objective:To identify the risk factors for acute graft-versus-host disease (aGVHD) in patients with acute myeloid leukemia (AML) undergoing haploidentical hematopoietic stem cell transplantation (HID-HSCT) .Methods:A total of 141 AML patients who underwent HID-HSCT at the Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences, from January 2020 to July 2021 were included. The cumulative incidence of aGVHD was analyzed using the Fine-Gray competing risk model, with relapse and death as competing events, to compare differences between groups. Potential risk factors were evaluated by univariable and multivariable Cox proportional hazards regression analyses to determine their independent effects on aGVHD.Results:Among the 141 patients, 86 (61.0%) were male and 55 (39.0%) were female, with a median age at transplantation of 34 years. Within 100 days post-transplant, 59 patients developed grade Ⅱ-Ⅳ aGVHD, whereas 86 patients experienced no or grade Ⅰ aGVHD (the grade 0-Ⅰ aGVHD group) . Survival analysis showed that the 3-year overall survival was 68.7% (95% CI: 57.7%-81.9%) in the grade Ⅱ-Ⅳ aGVHD group, compared with 78.8% (95% CI: 70.4%-88.3%) in the grade 0 - Ⅰ aGVHD group, with the difference not being statistically significant ( P=0.190) . Univariable analysis identified donor age ( P=0.020, HR=1.020, 95% CI: 1.000-1.040) and the female donor-male recipient sex combination ( P=0.033, HR=1.980, 95% CI: 1.160-3.380) as risk factors for grade Ⅱ-Ⅳ aGVHD. Multivariable analysis confirmed that donor age ( P=0.005, HR=1.026, 95% CI: 1.008-1.047) and the female donor-male recipient sex combination ( P=0.002, HR=2.339, 95% CI: 1.354-4.037) were independent risk factors for aGVHD. Patients receiving grafts from donors aged >45 years had a significantly higher 100-day cumulative incidence of grade Ⅱ-Ⅳ aGVHD compared with those receiving grafts from donors ≤45 years [54.7% (95% CI: 42.3%-67.0%) vs 31.6% (95% CI: 21.0%-42.1%) , P=0.006]. Similarly, patients with the female donor-male recipient sex combination had a higher 100-day cumulative incidence of grade Ⅱ-Ⅳ aGVHD than those with other sex combinations [56.8% (95% CI: 40.4%-73.1%) vs 36.9% (95% CI: 27.5%-46.3%) , P=0.015]. Conclusion:Older donor age and the female donor-male recipient sex combination remain independent risk factors for aGVHD in patients with AML undergoing HID-HSCT.

Objective:To analyze the real-world practices of resecting sessile colorectal polyps of varying long diameters using cold forcep polypectomy (CFP), cold snare polypectomy (CSP), or endoscopic mucosal resection (EMR).Methods:A total of 12 290 nonpedunculated colorectal polyps of long diameter ≤19 mm (from 10 295 patients) were retrospectively enrolled from January 2022 to December 2023. Polypectomy was conducted by 30 endoscopists. The polyps were categorized into three groups based on long diameter: 1-5 mm, >5-10 mm and >10-19 mm, and the differences of polypectomy methods were compared in three groups. The usage of hemostatic clips in CSP among >5-10 mm polyps and the changes in resection methods between 2022 and 2023 were analyzed.Results:CFP (6 769 polyps, 81.7%) was the predominant method for resecting 1-5 mm sessile polyps (8 289 polyps). For sessile polyps sized >5-10 mm (2 455 polyps), CSP was used most (1 372, 55.9%), although its utilization varied significantly among physicians with the median usage rate of 52.9% (40.3%, 60.0%). EMR (1 349 poolyps, 87.3%) was the main method for >10-19 mm sessile polyps. The usage rate of CSP in sessile polypectomy for polyps >5-10 mm significantly increased from 45.7% (503/1 101) in 2022 to 64.2% (869/1 354) in 2023. The overall frequency of using clip in CSP for >5-10 mm sessile polyps was 40.1% (550/1 372), demonstrating notable variability among different endoscopists with median usage rate of 48.3% (29.8%, 67.9%).Conclusion:Varied resection methods are observed among endoscopists for sessile polyps measuring ≤19 mm. CFP is primarily utilized for polyps of 1-5 mm, while CSP is favored for polyps >5-10 mm, with an increasing annual usage rate. EMR is the main approach for the polyps >10-19 mm. Additionally, notable variations in the use of metal clips during CSP are observed among different physicians.

Objective:To investigate the clinical and endoscopic characteristics of patients with autoimmune gastritis (AIG).Methods:From January 1, 2013 to December 31, 2023, 73 AIG patients who visited Peking Union Medical College Hospital were retrospectively enrolled. The clinical data of all the patients were analyzed, including gender, age, symptoms, laboratory examination results (such as serum hemoglobin, vitamin B 12, serum iron, gastrin, anti-parietal cell antibody (APCA), anti-intrinsic factor antibody (AIFA), Helicobacter pylori ( HP) infection status; the indicators were judged based on the normal reference value), and endoscopic and histopathological examination results. Descriptive statistical methods were used for statistical analysis. Results:Among the 73 AIG patients, there were 27 males (37.0%) and 46 females (63.0%), with a median age of 57 years old (ranged from 25 to 85 years old). Among the 73 AIG patients, 68 patients received APCA test, with a positivity rate of 88.2% (60/68); 67 patients took the AIFA test, with a positivity rate of 52.2%(35/67); 62 patients underwent both APCA and AIFA tests, of which 22 patients (35.5%) showed double positive. Serum level of vitamin B 12 was detected in 59 patients, and decreased in 27 cases (median level: 0.100 ng/L, mean level: 0.102 ng/L). Gastrin level was detected in 58 patients, and increased in 55 cases (median level: 0.930 ng/L, mean level: 1.203 ng/L). The levels of serum iron and ferritin were tested in 52 patients, the level of serum iron of 5 cases decreased, and the level of ferritin of 17 cases decreased (median level: 780.0 and 26.0 μg/L, mean level: 807.8 and 76.0 ng/L, respectively).Among the 73 AIG patients, the urea breath test was performed in 12 patients, and the result was positive in 6 cases. Endoscopic rapid urease test was performed in 69 patients, and the result was positive in 11 cases (15.9%). Regular blood analysis was performed in 71 patients, 24 cases (33.8%) were diagnosed with anemia, the median age of patients with anemia was 55 years old, and male-to-female ratio was 1∶5. There were 6 cases of iron-deficiency anemia and 5 cases of pernicious anemia. The endoscopic examination results of 73 patients indicated that 65 cases (89.0%) with mucosal atrophy under endoscopy, including 47 cases (64.4%) with mucosal atrophy in the gastric fundus and body, and 18 cases (24.7%) with whole gastric atrophy, more obviously in the gastric body. The pathological examination results showed type Ⅰ gastric neuroendocrine tumor(g-NET) in 35 cases (47.9%). Conclusions:The early clinical symptoms of AIG patients are nonspecific, often present with anemia and vitamin B 12 deficiency. Close monitoring of serological markers including APCA, AIFA and gastrin is essential. For patients diagnosed or suspected with AIG, intervals of endoscopic surveillance should be shortened to prevent the genesis and development of neoplasms such as g-NET.

OBJECTIVE To explore the practice and application effect of lean Six Sigma (LSS) management in the cost-benefit management of PIVAS operation in a tertiary comprehensive hospital (hereinafter referred to as "S Hospital"),providing reference for the operation and management of PIVAS in hospitals.METHODS The five steps (define,measure,analyze,improve and control,i.e.DMAIC) of LSS management were implemented for PIVAS operation cost-benefit of S Hospital,and lean management was implemented for its cost-benefit management elements (human resource cost,medical and health material cost,and all-in-one parenteral nutrition preparation income).Several intervention measures including personnel training and performance assessment,refined management system of consumables,and doctor's advice package of full parenteral nutrition were developed.Finally,the overall improvement effect was evaluated by the total benefit,total cost and net benefit of PIVAS.The effects of human resource allocation optimization and improvement were evaluated by the work efficiency,work quality,job satisfaction,turnover rate and accumulated rest days.The effects of consumables cost management were evaluated by the amount of medical and health materials cost.The improvement effects of all-in-one parenteral nutrition preparation income were evaluated by the profit amount,quantity and the proportion of single bottle of parenteral nutrition.RESULTS After implementing DMAIC in S Hospital,the total benefit of PIVAS was increased from (471366.50±9201.5) yuan/month to (479679.50±14320.14) yuan/month (P>0.05),the total cost was decreased from (305878.88±3201.75) yuan/month to (294610.59±5007.33) yuan/month (P<0.05),and the net benefit of PIVAS was increased by 11.83％ compared with that before the improvement.The work efficiency,work quality and job satisfaction of employees were significantly improved,the accumulated rest days were significantly reduced,and the turnover rate of third-party employees was reduced from 15.0％ before the improvement to 7.5％ after the improvement.The cost of medical and health materials significantly decreased from (67826.42±2812.76) yuan/month before improvement to (56384.33±4607.67) yuan/month after improvement (P<0.05).The quantity of all-in-one parenteral nutrition was significantly increased from (1263.75±135.83)group/month before improvement to (2061.25±89.04) group/month after improvement (P<0.05),and the proportion of users of single bottle of parenteral nutrition in total users decreased from 93.25％ before improvement to 58.75％ after improvement.The profit of all-in-one parenteral nutrition was 63.18％ higher than that before implementing DMAIC.CONCLUSIONS The implementation of PIVAS operation cost-benefit management based on DMAIC is conducive to strengthening the cost control of PIVAS and promoting the healthy development of PIVAS.

Objective:To assess the efficacy of endoscopic transmural drainage, transpapillary drainage and their combination in reducing cyst recurrence in patients with disconnected pancreatic duct syndrome (DPDS).Methods:A retrospective study was conducted involving 22 patients diagnosed as having DPDS in Peking Union Medical College Hospital from January 2018 to December 2022. Patient data including clinical information, imaging characteristics, drainage technique, complications, and outcomes were extracted from the medical records and telephone follow-up.Results:There were 27 endoscopic treatments in 22 patients, which were categorized into 3 groups based on the procedural approach: transmural in 11 cases, transpapillary in 8, and the combination of both in 8. The combined drainage group exhibited a significantly higher drainage success rate (100.0%, 8/8) compared with the transpapillary group (50.0%, 4/8, P=0.012), with no significant difference compared with the transmural group [90.9% (10/11), P=0.621]. The one-year recurrence rate was significantly lower in the combined drainage group [0.0% (0/8)] than that in the transmural drainage group [55.6% (5/9), P=0.018], and transpapillary drainage alone [42.9% (3/7)] though it did not reach significance ( P=0.085). No significant differences were observed in treatment success rate [45.5% (5/11), 75.0% (6/8) and 87.5% (7/8), H=3.890, P=0.143], or complication incidence [54.5% (6/11), 75.0% (6/8) and 25.0% (2/8), H=3.909, P=0.142]. Conclusion:Transmural drainage combined with pancreatic duct stent placement results in satisfactory drainage of cystic fluid in the short term and significantly reduces one-year recurrence among patients with DPDS.