AIM:To compare the formation and release of neutrophil extracellular traps(NETs)af-ter exposure to the high-altitude hypoxic environ-ment for different periods,and their relationship with the dynamic changes of microcirculatory disor-ders associated with pulmonary edema.METH-ODS:SD rats were raised under normoxic condi-tions at an altitude of 400 m and under hypoxic conditions at an altitude of 4 200 m.The rats raised under hypoxic conditions at an altitude of 4 200 m for 7 days were returned to normoxic con-ditions at 400 m to observe the changes in physio-logical and pathological indicators of the rats.The dynamic changes of neutrophil extracellular traps(NETs)release and microcirculatory disorders relat-ed to pulmonary edema after high-altitude hypoxia exposure and after returning to the plain were ex-plored by blood routine determination,rat arterial blood gas analysis,ELISA experiment,lung water content determination,H&E staining,and immuno-histochemical staining.RESULTS:In the hypoxic en-vironment at 4 200 m,rats exhibited significant re-ductions in arterial oxygen saturation(SaO2)and partial pressure of oxygen(PO2)(P＜0.01),accompa-nied by a marked increase in lung-tissue water con-tent(P＜0.01).The complete blood count revealed elevated levels of red blood cells,white blood cells,lymphocytes,and neutrophils(P＜0.01).In addition,the formation and release of NETs in neutrophils in-creased,accompanied by an aggravation of the in-flammatory response.After returning to the low-al-titude normoxic area at 400 m,the above indica-tors gradually returned to normal levels on the 7th day.Pathological changes such as alveolar epitheli-al cell shedding and inflammatory cell infiltration were observed in the lung tissues of rats in the high-altitude area,and the pathological changes were restored after returning to the low-altitude normoxic environment.CONCLUSION:The release of NETs from neutrophils is closely related to the re-covery of pulmonary edema and pulmonary ede-ma-related microcirculatory disorders after high-al-titude hypoxia exposure.

AIM:To compare the formation and release of neutrophil extracellular traps(NETs)af-ter exposure to the high-altitude hypoxic environ-ment for different periods,and their relationship with the dynamic changes of microcirculatory disor-ders associated with pulmonary edema.METH-ODS:SD rats were raised under normoxic condi-tions at an altitude of 400 m and under hypoxic conditions at an altitude of 4 200 m.The rats raised under hypoxic conditions at an altitude of 4 200 m for 7 days were returned to normoxic con-ditions at 400 m to observe the changes in physio-logical and pathological indicators of the rats.The dynamic changes of neutrophil extracellular traps(NETs)release and microcirculatory disorders relat-ed to pulmonary edema after high-altitude hypoxia exposure and after returning to the plain were ex-plored by blood routine determination,rat arterial blood gas analysis,ELISA experiment,lung water content determination,H&E staining,and immuno-histochemical staining.RESULTS:In the hypoxic en-vironment at 4 200 m,rats exhibited significant re-ductions in arterial oxygen saturation(SaO2)and partial pressure of oxygen(PO2)(P＜0.01),accompa-nied by a marked increase in lung-tissue water con-tent(P＜0.01).The complete blood count revealed elevated levels of red blood cells,white blood cells,lymphocytes,and neutrophils(P＜0.01).In addition,the formation and release of NETs in neutrophils in-creased,accompanied by an aggravation of the in-flammatory response.After returning to the low-al-titude normoxic area at 400 m,the above indica-tors gradually returned to normal levels on the 7th day.Pathological changes such as alveolar epitheli-al cell shedding and inflammatory cell infiltration were observed in the lung tissues of rats in the high-altitude area,and the pathological changes were restored after returning to the low-altitude normoxic environment.CONCLUSION:The release of NETs from neutrophils is closely related to the re-covery of pulmonary edema and pulmonary ede-ma-related microcirculatory disorders after high-al-titude hypoxia exposure.

Objective:To investigate the differences of gastric mucosa microbiota between children with chronic gastritis and duodenal ulcer under the condition of Helicobacter pylori (Hp) infection. Methods:This prospective cohort study involved 57 children with Hp infection diagnosed by gastric endoscopy who were admitted to the Children′s Hospital of Zhejiang University School of Medicine due to "abdominal pain, abdominal distension and vomiting" between January 2018 to August 2018. According to gastroscopy and pathological examination, the children were divided into chronic gastritis group and duodenal ulcer group. Gastric mucosa from Hp infected patients were sampled, and the flora DNA was analyzed by high-throughput sequencing. The statistical difference of α diversity, β diversity between two groups were analyzed. The relative abundance of the two groups in each taxonomic level was analyzed statistically. T test, Rank sum test or χ 2 test was used for comparison between the two groups. Results:A total of 57 children diagnosed with Hp infection were enrolled in this study, including 42 cases of chronic gastritis (the age was (9.3±2.8) years, 22 males and 20 females) and 15 cases of duodenal ulcer (the age was (11.1±3.3) years, 9 males and 6 females). Alpha diversity index Chao and ACE in Hp infected chronic gastritis group were significantly higher than those in Hp infected duodenal ulcer group (217±50 vs. 183±64, t=2.088, P=0.009;218±47 vs. 192±76, t=1.566, P=0.016, respectively). The Beta-diversity index such as nonmetric multidimensional scaling (NMDS) analysis were significantly different in the two groups (analysis of similarity R=0.304, P=0.028). Among the main bacteria genera, there were 6 genera with significant differences between the two groups, which were Prevotella (0.190% (0.008%-1.983%) vs. 0.021% (0.005%-2.398%), Z=-2.537, P=0.011), Alloprevotella (0.097% (0.010%-0.813%) vs. 0.015% (0.003%-0.576%), Z=-2.492, P=0.013), Haemophilus (0.109% (0.004%-0.985%) vs. 0.014% (0.004%-0.356%), Z=-2.900, P=0.004), Neisseria (0.074% (0.004%-0.999%) vs. 0.024% (0.003%-0.255%), Z=-2.718, P=0.007), Streptococcus (0.166% (0.008%-1.869%) vs. 0.045% (0.006%-0.879%), Z=-2.537, P=0.010), and an unclassified- Microbacteriaceae (0.214% (0.060%-1.762%) vs. 0.117% (0.010%-0.954%), Z=-2.120, P=0.034). Linear discriminant analysis (LDA) effect sized analysis showed that at the genus level, only Prevotella was significantly enriched in the duodenal ulcer group (LDA=2.90, P=0.010), while Streptococcus, Neisseria and Haemophilus were significantly enriched in the chronic gastritis group (LDA=2.83, 2.82, 2.69, P=0.011, 0.007, 0.004, respectively). Conclusions:The gastric mucosal microbiota in duodenal ulcer associated with Hp is significantly different from that in chronic gastritis. Hp may promote the occurrence of peptic ulcer together with gastric microbiota.

Objective: To explore the clinical features and complications of foreign bodies in the upper gastrointestinal tract in children and to investigate the effectiveness of endoscopic management. Methods: Data of patients with foreign bodies in upper gastrointestinal tract were collected retrospectively at Endoscopy Center, the Children's Hospital, Zhejiang University School of Medicine, from January 2011 to December 2016. Clinical characteristics, the types of foreign bodies, the location and duration of foreign body impaction were summarized. The risk factors of complications and endoscopic removal failure were analyzed by using Logistic regression analysis. Results: A total of 1 334 patients (825 males and 509 females) were enrolled. The median age was 2.5 years, with a range from 0.25 to 15 years and peak age 1-3 years. Twenty patients had esophageal diseases. The most common foreign body ingested was coin (n=964, 72.3%). Foreign bodies were most commonly located in the esophagus (n=1 002, 75.1%), especially in the upper esophagus (n=857, 85.5%). The duration of foreign body impaction ranged from 3 hours to 5 years. Among 1 334 patients, 252 patients (18.9%) developed complications, including ulcers (n=101, 40.0%) and perforations(n=13, 5.2%). The success rate of endoscopic removal was 96.6% (n=1 288). By Logistic regression analysis, sharp foreign body ingestion (OR=6.893, 95%CI: 4.421-10.746) , esophageal impaction (OR=5.253, 95%CI:3.352-8.233) and foreign body impaction longer than 24 hours (OR=4.336, 95%CI:3.091-6.082) were risk factors of complications. Sharp foreign body ingestion was the risk factor of endoscopic failure (OR=5.372, 95%CI:2.773-10.406) . Conclusions Coin is the most common foreign body in upper gastrointestinal tract. Sharp foreign bodies impacted in the esophagus over 24 hours increase the risk of complications. Endoscopic removal of foreign bodies from the upper gastrointestinal tract in children has a high success rate. Sharp foreign body ingestion increases the risk of failure in endoscopic removing.