Objective:To observe the efficacy of maintenance treatment of thiopurines after exclusive enteral nutrition (EEN) therapy for Crohn′s disease (CD) children, and explore the influencing factors of recurrence.Methods:A retrospective case-control study was conducted. CD children treated in the Children′s Hospital of Zhejiang University School of Medicine from March 2013 to March 2021 were included retrospectively. Data before EEN were collected including general demographics, Paris classification, the pediatric Crohn′s disease activity index (PCDAI), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and serum albumin levels. According to the recurrence at 1 year of follow-up, patients were divided into remission group and recurrence group. The differences in clinical data before EEN between the 2 groups were analyzed. The factors influencing the recurrence were analyzed.Results:Thirty-five children were enrolled, including 25 (71.4%) males and 10 (28.6%) females. The age at diagnose was (11.2 ± 3.1) years old and the disease duration was 3.5 (2.2, 6.9) months. After 1 year of follow-up, 15 children had recurrence at least for one time and were divided into the recurrence group. Twenty (57.1%) children continued to maintain 6-mercaptopurine (6-MP) monotherapy and were divided into the remission group. There was no significant differences in gender, diagnostic age, and CRP, ESR, serum albumin and PCDAI before EEN between the two groups (all P>0.05). There was significant difference in the percentage of patients with disease duration of longer than 1 year before EEN between the two groups ( P = 0.026) . Conclusions:The children with the disease duration of longer than 1 year before EEN may be in high risk of recurrence on the regimen of maintenance treatment of thiopurines after EEN.

Objective:To explore the incidence and the risk factors of post-polypectomy bleeding and polyp recurrence after colonoscopic high-frequency electrocoagulation snare polypectomy.Methods:Clinical data of 1 826 children who underwent colonoscopic high-frequency electrocoagulation snare polypectomy in the Children′s Hospital, Zhejiang University School of Medicine from January 2009 to December 2020 was retrospectively analyzed. Demographic characteristics, endoscopic manifestations, pathological features, diagnosis, occurrence of post-polypectomy bleeding and polyp recurrence were collected. The associated risk factors were analyzed by Logistic regression.Results:A total of 1 826 children (1 191 males and 635 females) with 1 967 polypectomies were included. The age was 4.6 (3.2, 6.4) years at initial diagnosis. According to the initial colonoscopy, 1 611 children (88.2%) had solitary polyps, 1 707 children (93.5%) had pedicled polyps, 1 151 children (63.0%) had polyps involving the rectum, and 1 757 children (96.2%) had hamartomatous polyps. Polyposis syndromes were diagnosed in 73 children (4.0%). The post-polypectomy bleeding occurrence was 3.8% (75/1 967). Polyps recurred in 88 children (4.8%). Girls ( OR=2.01, 95% CI 1.26-3.23) and sessile polyps ( OR=2.28, 95% CI 1.15-4.49) were risk factors for post-polypectomy bleeding (both P<0.05). Multiple polyps ( OR=17.49, 95% CI 9.82-31.18), right-colon involvement ( OR=3.44, 95% CI 1.89-6.26) and non-hamartoma ( OR=2.51, 95% CI 1.04-6.07) were risk factors for polyp recurrence (all P<0.05). Conclusions:Colonoscopic high-frequency electrocoagulation snare polypectomy has low incidence of post-polypectomy bleeding and polyp recurrence. Female patients and sessile polyps have higher risk for post-polypectomy bleeding. Multiple polyps, right-colon involvement and non-hamartoma polyps increase the risk for polyp recurrence.

Objective:To analyze the changes of common pathogens of viral diarrhea in children during the COVID-19 epidemic.Methods:A retrospective analysis was performed on children with acute diarrhea treated in Children’s Hospital affiliated to Zhejiang University School of Medicine from 2019 April to 2019 December(before COVID-19, n=407)and 2020 April to 2020 December (during COVID-19, n=645). Children were further divided into 1-6 months, >6 months-2 years, >2-5 years age groups. Detection rates of norovirus GI (NOVI), norovirus GⅡ (NOVⅡ), rotavirus A (ROVA), rotavirus C (ROVC), intestinal adenovirus (EADV), sapovirus (SAV) and astrovirus (ASV) in different age groups and seasons before and during COVID-19 were compared by χ2 or Fisher exact test. Results:The total detection rates of diarrhea-causing viruses among age groups were significantly higher before COVID-19 than those during COVID-19( χ2=8.43, 38.22 and 9.23, all P<0.05). The detection rates of NOVⅡ and EADV in infants aged 1-6 months and >6 months-2 years were decreased during the period of COVID-19 epidemic( χNOVⅡ2 =36.87 and 17.77, both P<0.001, χEADV2 =9.08, P=0.014 and 0.003); the detection rates of NOVⅡ in children aged 2-5 years was decreased during the period of COVID-19 epidemic( χ2=3.96, P=0.047); the detection rates of other diarrhea-causing viruses were not decreased during the period of COVID-19 epidemic(all P>0.05). The detection rates of diarrhea-causing viruses among 4-6 months, 7-9 months and 10-12 months were higher during the period of COVID-19 epidemic( χ2=11.62, 65.41 and 27.80, all P<0.001). Conclusion:After the outbreak of COVID-19, the detection rate of common pathogens of viral diarrhea in children is decreased, especially NOVⅡ and EADV, which may be related to the measures in response to major public health events in Zhejiang Province.

Objective:To observe the efficacy of maintenance treatment of thiopurines after exclusive enteral nutrition (EEN) therapy for Crohn′s disease (CD) children, and explore the influencing factors of recurrence.Methods:A retrospective case-control study was conducted. CD children treated in the Children′s Hospital of Zhejiang University School of Medicine from March 2013 to March 2021 were included retrospectively. Data before EEN were collected including general demographics, Paris classification, the pediatric Crohn′s disease activity index (PCDAI), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and serum albumin levels. According to the recurrence at 1 year of follow-up, patients were divided into remission group and recurrence group. The differences in clinical data before EEN between the 2 groups were analyzed. The factors influencing the recurrence were analyzed.Results:Thirty-five children were enrolled, including 25 (71.4%) males and 10 (28.6%) females. The age at diagnose was (11.2 ± 3.1) years old and the disease duration was 3.5 (2.2, 6.9) months. After 1 year of follow-up, 15 children had recurrence at least for one time and were divided into the recurrence group. Twenty (57.1%) children continued to maintain 6-mercaptopurine (6-MP) monotherapy and were divided into the remission group. There was no significant differences in gender, diagnostic age, and CRP, ESR, serum albumin and PCDAI before EEN between the two groups (all P>0.05). There was significant difference in the percentage of patients with disease duration of longer than 1 year before EEN between the two groups ( P = 0.026) . Conclusions:The children with the disease duration of longer than 1 year before EEN may be in high risk of recurrence on the regimen of maintenance treatment of thiopurines after EEN.

Objective:To understand the knowledge awareness and service acceptance of HIV non-occupational post-exposure prophylaxis (nPEP) men who have sex with men (MSM) among college students in three cities of China.Methods:Male college students in 10 universities of Beijing, Shenzhen and Kunming aged 18 and above who had sex with men in the last 3 months were recruited as research objects by cluster stratified sampling from March 15, 2019 to April 14, 2019.Basic information, sexual behavior characteristics, knowledge, and service acceptance of nPEP were collected through online questionnaire survey. Multivariate dichotomy and unconditioned logistic regression model was used to explore related factors about knowledge awareness and service acceptance of nPEP.Results:A total of 293 MSM were surveyed. The average age was (21.0±0.2) years old, and 91.1% (267) were undergraduates. In the last 3 months before the survey, 54.3%(159) used condom each time of sex; 4.4%(13) had intercourse with the HIV infected men, and 9.2% (27)suffered STDs in the past 6 months. The 29.4% (86) had not received HIV testing in the past year. The nPEP knowledge awareness rate was 47.8% (140). The 21.2% (62) counseled nPEP services, and 9.9% (29) received nPEP services. After multiple logistic regression analysis, compared with those who not received HIV testing in the past year, OR(95% CI) value of those who received HIV testing for more than twice in the past year to aware the nPEP knowledge was 3.15 (1.01-9.86). Compared with those who not received HIV testing in the past year, OR(95% CI) value of those who received HIV testing for more than twice in the past year to counsel the nPEP services was 5.29 (1.51-18.51). Compared with those who never used rush in the last 3 months, OR(95% CI) value of those who ever used rush in the last 3 months to receive the nPEP services was 3.86 (0.99-14.98). Compared with those who not sexed with HIV infected in the last 3 months, OR (95% CI) value of those who sexed with HIV infected in the last 3 months to receive the nPEP services was 14.30 (3.35-61.03). Conclusion:The proportions of awareness of nPEP knowledge and acceptance of nPEP services are low. MSM among college students need further health education of the nPEP knowledge to improve the accessibility of services.

Objective:To understand the knowledge awareness and service acceptance of HIV non-occupational post-exposure prophylaxis (nPEP) men who have sex with men (MSM) among college students in three cities of China.Methods:Male college students in 10 universities of Beijing, Shenzhen and Kunming aged 18 and above who had sex with men in the last 3 months were recruited as research objects by cluster stratified sampling from March 15, 2019 to April 14, 2019.Basic information, sexual behavior characteristics, knowledge, and service acceptance of nPEP were collected through online questionnaire survey. Multivariate dichotomy and unconditioned logistic regression model was used to explore related factors about knowledge awareness and service acceptance of nPEP.Results:A total of 293 MSM were surveyed. The average age was (21.0±0.2) years old, and 91.1% (267) were undergraduates. In the last 3 months before the survey, 54.3%(159) used condom each time of sex; 4.4%(13) had intercourse with the HIV infected men, and 9.2% (27)suffered STDs in the past 6 months. The 29.4% (86) had not received HIV testing in the past year. The nPEP knowledge awareness rate was 47.8% (140). The 21.2% (62) counseled nPEP services, and 9.9% (29) received nPEP services. After multiple logistic regression analysis, compared with those who not received HIV testing in the past year, OR(95% CI) value of those who received HIV testing for more than twice in the past year to aware the nPEP knowledge was 3.15 (1.01-9.86). Compared with those who not received HIV testing in the past year, OR(95% CI) value of those who received HIV testing for more than twice in the past year to counsel the nPEP services was 5.29 (1.51-18.51). Compared with those who never used rush in the last 3 months, OR(95% CI) value of those who ever used rush in the last 3 months to receive the nPEP services was 3.86 (0.99-14.98). Compared with those who not sexed with HIV infected in the last 3 months, OR (95% CI) value of those who sexed with HIV infected in the last 3 months to receive the nPEP services was 14.30 (3.35-61.03). Conclusion:The proportions of awareness of nPEP knowledge and acceptance of nPEP services are low. MSM among college students need further health education of the nPEP knowledge to improve the accessibility of services.

Objective To investigate the short- to medium-term therapeutic effects of a new internal fixation device,intraosseous internal fixation(IO-FIX),in the foot-ankle arthrodesis.Methods From August 2016 to December 2018,32 patients(40 feet) underwent foot-ankle arthrodesis with IO-FIX at Department of Orthopaedic Surgery,The Ninth Peopled Hospital of Shanghai.They were 6 males and 26 females,aged from 23 to 83 years(61.7±15.1 years).There were 28 cases(36 feet) of hallux valgus,2 cases(2 feet) of ankle arthritis,one case(1 foot) of ankle rheumatoid arthritis and one case(1 foot) of naviculocuneiform arthrosis.The therapeutic effects were assessed in terms of imaging evaluation,American Orthopaedic Foot and Ankle Society(AOFAS) score,fusion rate and full weight-bearing time.Results The follow-up ranged from 3.0 to 31.3 months(mean,12.6 months).The total fusion rate was 95.0%(38/40);the total AOFAS score increased significantly from preoperative 41.9±9.5 to postoperative 86.9±4.7(P<0.05).The 28 patients(36 feet) with hallux valgus achieved a successful fusion rate of 97.2%(35/36) and full weight-bearing at 8 weeks after operation.Their fusion time ranged from 45 to 64 days(57.1 days).Their metatarsophalangeal angle was decreased significantly from 52.10±13.50 preoperatively to 13.40±4.90 postoperatively and their 1-2 intermetatarsal angle significantly from 14.5°±2.4°to 8.90±2.4°(P<0.05).Their AOFAS ankle-hindfoot score was improved significantly from 41.8±9.9 to 87.0±4.8(P<0.05).All the 3 cases of ankle arthrodesis achieved good bone union and full weight-bearing within 12 weeks and their AOFAS ankle-hindfoot score was improved significantly from preoperative 43.4±3.5 to 86.3±3.5 at the final follow-up.Conclusion In foot-ankle joint arthrodesis,due to advantages of stable fixation,zero profile,limited soft tissue irritation,reinforced bone bridge and easy reproducibility,10-FIX can lead to satisfactory short- to mid-term therapeutic effects.

Objective To evaluate the validity and security of our self-designed bone marrow stem cell Screen-Enrich-Combine(-Biomaterials) Circulating System(SECCS) for bone non-union of limbs. Methods From May 2013 to December 2015, 24 patients with limb non-union were treated at our de-partment. They were aged from 20 to 65 years (mean, 42.8 years). Their non-union involved femur in 17 cases, tibia in 4, radius in one, humerus in one and fibula in one. In surgery, 80 mL bone marrow blood was aspirated from the anterior superior iliac spine for rapid preparation of bone substitute(β-TCP)composite with bone marrow stem cells by SECCS which was then implanted at the non-union locations. The bone marrow blood was collected before and after enrichment for stem cell counts. The bone union, clinical union time and related com-plications were evaluated by follow-up X-rays at 1, 3, 6 and 9 months after surgery. Results Each collection of bone marrow blood took 13.5 minutes on average. The enrichment rate of stem cells was 81.2%. 11,751 ± 1,011 stem cells were implanted per patient on average. All the patients were followed up for 9 to 48 months (mean, 19.2 months). Twenty-two patients acquired clinical union 9 months after operation and the other 2 suffered from malunion due to insufficient bone implant, yielding a union rate of 91.6% and an average union time of 6.5 months. No graft infection or internal fixation failure occurred and no severe complications hap-pened at the donor or implant sites.Conclusion The bioactive bone substitute manufactured by our self-designed SECCS can be used as a novel therapy for limb non-union, and this device is moreover charac-terized with convenience, limited invasion and satisfactory osteogenesis so that complications of autologous bone transplantation can be avoided.

Objective To introduce a new method for preparation of bioactive β-tricalcium phosphate (β-TCP) by rapid stem cell screen-and-enrich-and-combine circulating system (SECCS) and evaluate its efficacy in the treatment of fresh fractures and bone defects.Methods Twenty-two patients with fresh fracture and bone defects were treated with SECCS from July 2013 to April 2016.They were 16 males and 6 females with an average age of 52.2 years (from 27 to 81 years).There were 15 tibial plateau fractures and 7 calcaneal fractures.The average size of bone defects was 12.5 mL.Bioactive β-TCP was prepared by SECCS intraoperatively and implanted back immediately into the bone defects.Radiographic examination,Lysholm knee scoring and Maryland foot scoring were used for assessment of curative efficacy.Results The 22 patients were followed up for an average of 25.7 months (from 12 to 46 months).By SECCS,the enrichment efficiency of bone marrow stromal cells (BMSCs) reached up to 82.4％ and the cell viability was not affected.The tibial plateau fractures were re-transplanted with 13,381.3 BMSCs on average and healed after an average of 8.9 weeks (from 6 to 15 weeks).The Lysholm knee scores at one year postoperatively averaged 93.6 points (from 84 to 100 points),yielding 10 excellent cases,4 good cases and one fair case.The calcaneal fractures were implanted back with 16,677.7 BMSCs on average and healed after an average of 9.4 weeks (from 8 to 13 weeks).The average Maryland foot score at one year after operation was 93.6 points (from 85 to 98 points),yielding 6 excellent cases and one good case.Conclusion Bioactive materials prepared by SECCS are good bone grafts for fresh fractures and bone defects.

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.