Esophageal stricture is a common esophageal lesion in adults and children, and endoscopic dilatation is currently the standard treatment. However, high recurrence rate and frequent dilations have become a major problem in patients. Esophageal stents provide sustained dilation therapy but can lead to serious complications such as displacement, perforation, and bleeding, necessitating removal. Biodegradable stents, with the advantage of both dilation and self-degradation, are promising potential solutions to this problem. Currently, biodegradable materials are mainly categorized into metals and polymers, leading to the development of magnesium alloy esophageal stents and polymer esophageal stents. Among polymer stents, poly-L-lactic acid (PLLA) stents and SX-ELLA stents have been put into clinical application. In recent years, with the advancement of 3D bioprinting technology, the personalized fabrication of biodegradable stents has become feasible. In this paper, we will outline the current research status and progress of biodegradable magnesium alloy stents and polymer stents, introduce the new process of constructing esophageal stents by 3D bioprinting technology, focusing on the clinical research of SX-ELLA stents in pediatric and adult patients. We will also analyze the existing problems with biodegradable stents and the directions for future development.

Objective To explore the hepatotoxicity of Dioscoreae Bulbiferae Rhizoma and its molecular mechanism using transcriptomics.Methods Totally 40 SPF-grade male Kunming mice were randomly divided into the normal control group and Dioscoreae Bulbiferae Rhizoma low-,medium-and high-dosage groups,and were orally administered with the decoction of Dioscoreae Bulbiferae Rhizoma for 14 days.Serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST)contents were detected,HE staining was used for morphology examination of the liver and scoring,transcriptomic analysis was conducted to detect the gene expression of liver tissue,differentially expressed genes were subjected to GO and KEGG pathway enrichment analysis,serum alkaline phosphatase(ALP)and total bile acid(TBA)content in liver tissue were detected,Western blot was used to validate key targets.Results Compared with the normal control group,Dioscoreae Bulbiferae Rhizoma high-dosage group showed an increase in serum ALT and AST contents(P<0.05),with hepatic cell edema,increased volume,dilated hepatic sinusoids,necrosis in some areas,and elevated pathological score(P<0.05).Transcriptomic analysis revealed that after intervention with Dioscoreae Bulbiferae Rhizoma,differentially expressed genes in liver tissue were mainly enriched in cholesterol metabolism process,steroid metabolism process,cholesterol biosynthesis process,and signaling pathways such as steroid biosynthesis,cholesterol metabolism,bile secretion and primary bile acid biosynthesis.The experimental verification results showed that serum ALP and liver tissue TBA content in Dioscoreae Bulbiferae Rhizoma high-dosage group increased(P<0.05),as well as HMGCS1 and CYP51A1,the expressions of CYP27A1 and CYP7A1,which promoted cholesterol conversion to bile acids in liver tissue increased(P<0.05,P<0.01),while the expression of multidrug resistance protein 4(MRP4),which promoted bile acid excretion decreased(P<0.05).Conclusion Dioscoreae Bulbiferae Rhizoma inducing liver toxicity is related to promoting cholesterol synthesis and conversion into bile acids,while inhibiting bile acid excretion.

Objective To explore the hepatotoxicity of Dioscoreae Bulbiferae Rhizoma and its molecular mechanism using transcriptomics.Methods Totally 40 SPF-grade male Kunming mice were randomly divided into the normal control group and Dioscoreae Bulbiferae Rhizoma low-,medium-and high-dosage groups,and were orally administered with the decoction of Dioscoreae Bulbiferae Rhizoma for 14 days.Serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST)contents were detected,HE staining was used for morphology examination of the liver and scoring,transcriptomic analysis was conducted to detect the gene expression of liver tissue,differentially expressed genes were subjected to GO and KEGG pathway enrichment analysis,serum alkaline phosphatase(ALP)and total bile acid(TBA)content in liver tissue were detected,Western blot was used to validate key targets.Results Compared with the normal control group,Dioscoreae Bulbiferae Rhizoma high-dosage group showed an increase in serum ALT and AST contents(P<0.05),with hepatic cell edema,increased volume,dilated hepatic sinusoids,necrosis in some areas,and elevated pathological score(P<0.05).Transcriptomic analysis revealed that after intervention with Dioscoreae Bulbiferae Rhizoma,differentially expressed genes in liver tissue were mainly enriched in cholesterol metabolism process,steroid metabolism process,cholesterol biosynthesis process,and signaling pathways such as steroid biosynthesis,cholesterol metabolism,bile secretion and primary bile acid biosynthesis.The experimental verification results showed that serum ALP and liver tissue TBA content in Dioscoreae Bulbiferae Rhizoma high-dosage group increased(P<0.05),as well as HMGCS1 and CYP51A1,the expressions of CYP27A1 and CYP7A1,which promoted cholesterol conversion to bile acids in liver tissue increased(P<0.05,P<0.01),while the expression of multidrug resistance protein 4(MRP4),which promoted bile acid excretion decreased(P<0.05).Conclusion Dioscoreae Bulbiferae Rhizoma inducing liver toxicity is related to promoting cholesterol synthesis and conversion into bile acids,while inhibiting bile acid excretion.

Objective:To determine the risk factors of reoperation and mortality after complete atrioventricular septal defect repair, and to evaluate the medium and long-term prognosis.Methods:From March 2008 to March 2022, a total of 266 children were selected from the Department of Thoracic and Cardiovascular Surgery, Nanjing Children's Hospital, who underwent the complete atrioventricular septal defect repair. Exclusion of children with conotrucal anomaly such as tetralogy of Fallot, transposition of the great arteries, and right ventricular double outlet. Demographic characteristics, surgical data, postoperative follow-up and associated risk factors were analyzed.Results:All the children were repaired with modified single-piece method for the first time, and 26 children were reoperated because of severe left atrioventricular valve regurgitation, left ventricular outflow tract obstruction and atrioventricular block. The 1-year, 3-year and 5-year overall survival rate and freedom from reoperation rate of all children were (98.1±0.8)%, (97.3±1.0)%, (96.2±1.2)%, (96.6±1.1)%, (93.9±1.5)% and (92.2±1.7)%, respectively. A total of 11 (42.3%) early reoperations and 15 (57.7%) late reoperations were performed, of which 1-year, 3-year and 5-year survival rates were (92.3±5.2)%, (82.1±8.3)% and (76.6±9.4)% respectively. Multifactorial analysis showed that age <3 months and left atrioventricular regurgitation >grade 2 at 24 hours postoperatively were independent risk factors for reoperation, whereas age <3 months and experience of reoperation were independent risk factors for death of children.Conclusion:Complete atrial septal defects have excellent surgical outcomes, but some children still require reoperation, and age <3 months and postoperative left atrioventricular valve regurgitation(LAVVR)>2 grades remain important predictors of their surgical prognosis.

Objective:To analyze the early and middle term clinical effects of mitral valve repair in children with mitral insufficiency.Methods:From January 2012 to January 2019, a total of 202 cases of children with mitral insufficiency treated by mitral valve repair were selected from the department of cardiothoracic surgery of Nanjing Children's Hospital, patients with atrioventricular septal defect, single ventricle and ischemic mitral regurgitation were excluded. Echocardiography was used to compare the preoperative and postoperative left ventricular function and degree of regurgitation in children to evaluate the early and middle term efficacy of mitral valvuloplasty.Results:There were 5 cases of early death(5/202, 2.5%) and 3 cases of late death(3/202, 1.5%). The mean follow-up time was(19.49±17.48) months(1-68 months). Postoperative echocardiography showed that the left heart function and mitral regurgitation were significantly improved.Conclusion:Mitral valvuloplasty can significantly correct mitral insufficiency in children, and it has satisfactory mid-term efficacy and good clinical value.

Objective:To investigate the common types, surgical treatment and effects of tracheal stenosis in children.Methods:A total of 23 children with tracheal stenosis in our hospital from December 2017 to August 2020 were retrospectively reviewed, including 14 males and 9 females. The mean age at operation was(8.9±5.8)months(range: 2-3 months) and the mean weight was(6.4±2.3)kg(range: 4.2-10.5 kg). The common types of tracheal stenosis were complete tracheal ring in 9 children, tracheomalacia in 10 and subglottic membranous annular hyperplasia in 4. The type of congenital heart diseases included 10 patients of pulmonary artery sling, 1 of tetralogy of Fallot, 5 of ventricular septal defect, 1 of pulmonary atresia, and 1 of right aortic arch with aberrant left subclavian artery. Slide tracheoplasty was performed in 9 patients, external splint in 8, endotracheal stent in 2 and tracheal dilation in 4. All children were followed up after 1, 3, 6, and 12 months of operation with CT and bronchoscopy.Results:There was 1 death in all 23 patients and the mortality was 4.3%, which died of granulation tissue hyperplasia after slide tracheoplasty. Reoperation was performed in 1 patient with endotracheal stent. All patients were followed for 1 to 24 months. Clinical symptoms of tracheal stenosis disappeared and the results of CT and bronchoscopy were satisfied.Conclusion:Slide tracheoplasty is the effective surgical method for complete trachea ring. 3D printing bioresorbable external splint is a promising method for the treatment of tracheomalacia.

OBJECTIVETo compare the efficacy of thoracoscopic surgery versus thoracotomy in repairing esophageal atresia type Ⅲ with tracheoesophageal fistula (EA/TEF) in neonates.

METHODSA retrospective analysis was conducted in 97 neonates who underwent EA/TEF repair between January 2012 and December 2017 in the Affiliated Children's Hospital of Nanjing Medical University, including 75 patients receiving thoracotomy and 22 patients receiving thoracoscopic surgery. The perioperative data and the incidence of early postoperative complications were compared between two groups.

RESULTSThe operations were completed in all patients. One child (4.5%) in thoracoscopic surgery group was converted to thoracotomy with modified Livaditis procedure due to the long distance of two blind ends (>4 cm) and thinner distal end. The operation time was longer in thoracoscopic surgery group[(143±48) min vs. (120±40) min, <0.05], but the postoperative ventilation time was shorter[(55±22) h vs. (65±19) h, <0.05] and the first oral feeding was earlier in thoracoscopic surgery group[(3.2±1.1) d vs (3.9±1.3) d, <0.05]. No statistical difference was observed in the ratio of red blood cell transfusion, length of hospital stay and drainage tube indwelling time between two groups (all >0.05). The incidence of lung complications in thoracotomy group was higher than that in thoracoscopic surgery group (20.0% vs. 9.1%, <0.01), while there were no significant differences in the incidence of other postoperative complications between two groups. There was no death in thoracoscopic surgery group, while 2 patients died in thoracotomy group.

CONCLUSIONSThoracoscopic repair is a preferred surgical procedure for EA/TEF in neonates.

Objective To investigate the related factors for the survival of the patients with pancreatic cancer.Methods A total of 1 620 patients confirmed as pancreatic cancer admitted in Sun Yat-sen Memorial Hospital affiliated with Sun Yat-sen University,Tumor prevention and treatment center affiliated with Sun Yat-sen University and People's Hospital of Guangdong Province from 2004 to 2016 were retrospectively analyzed,and the effects of TNM staging,surgical treatment,palliative chemotherapy and postoperative assisted chemotherapy on the survival of the patients with pancreatic cancer were examined by life table and Log-rank test.Results The median survival time of all 1 620 cases was 7.15 months.The median survival time of TNM stage Ⅰ,Ⅱ,Ⅲ and Ⅳ was 12.50 months,10.12 months,9.56 months and 5.43 months,and there was statistically significant difference (P =0.001).The median survival time of cases who did not undergo surgery was 6.10 months,which of patients who underwent radical surgery was 13.67 months,and the difference was statistically significant (P =0.001).The median survival time of cases without chemotherapy was 5.55 months,which of patients who underwent palliative chemotherapy was 7.58 months,and the difference was statistically significant (P =0.001).The median survival time of cases with pure radical surgery without chemotherapy was 12.38 months,which of patients who underwent adjuvant chemotherapy was 14.50 months,and the difference was no statistically significant (P =0.561).Conclusions Early diagnosis followed closely by radical surgery is the key to prolong the survival of pancreatic cancer patients.And adjuvant chemotherapy for patients who lose surgery opportunity may improve clinical prognosis to a certain extent.

Objective To analyze the operation of long-term effect of edge to edge mitral repair for mitral vavle moderateto-severe insufficiency in children retrospectively.Methods Clinical dates of 102 patients who underwent edge to edge mitrel valve repair in Nanjing Children's Hospital from March 2003 to March 2015 were collected.Postoperative thoracic echocardiography was adopted to observe the effect of mitral valve forming and evaluate the follow-up results.Results The whole group of 2 patients died in hospital,Followed up for 1 months to 12 years,during the follow-up of 10 patients were lost.The early fol low-up,medium-term follow-up and long-term follow-up were completed 93,55 and 26 cases,respectively.In the early followup,6 patients had recurrent moderate mitral regurgitation(MR),and 5 patients had recurrent moderate-to-severe MR and reoperated during the follow-up period,a total of 2 cases died.In the medium-term follow up,moderate and severe MR were found in 6 and 4 cases,respectively.Three patients accepted reoperation,two patients died.In the long-term follow-up,1 case had recurrent severe MR,2 cases had re-operation and had no death.Early survival rate was 97.8 ％ (91/93),avoid reoperation rate was 94.6％ (88/93).The incidence of moderate or severe mitral regurgitation was 11.8％ (11/93).Midtcrm survival rate was 96.4％ (53/55),avoid reoperation rate was 94.6％ (52/55),moderate or severe mitral regurgitation rate was 18.2％ (10/55).Long-term follow-up have no death,avoid reoperation rate was 92.3 ％ (24/26),mitral valve moderate and above reflux rate was 7.7 ％ (2/26).The actuarial survival and freedom from MV reoperation rate was (92.4 ± 2.4) ％ and (77.7 ± 6.4) ％ at 10 years,respectively.Conclusion Edge to edge mitral repair in the treatment of children with moderate to severe mitral insufficiency had relatively stable curative effect,relatively fewer complications,and high long-term clinical effect.