Objective To explore the establishment of a prognostic model based on machine learning algorithm to predict primary graft dysfunction(PGD)in patients with idiopathic pulmonary fibrosis(IPF)after lung transplantation.Methods Clinical data of 226 IPF patients who underwent lung transplantation were retrospectively analyzed.All patients were randomly divided into the training and test sets at a ratio of 7∶3.Using regularized logistic regression,random forest,support vector machine and artificial neural network,the prognostic model was established through variable screening,model establishment and model optimization.The performance of this prognostic model was assessed by the area under the receiver operating characteristic curve(AUC),positive predictive value,negative predictive value and accuracy.Results Sixteen key features were selected for model establishment.The AUC of the four prognostic models all exceeded 0.7.DeLong and McNemar tests found no significant difference in the performance among different models(both P＞0.05).Conclusions Based on four machine learning algorithms,the prognostic model for grade 3 PGD after lung transplantation is preliminarily established.The overall prediction performance of each model is similar,which may predict the risk of grade 3 PGD in IPF patients after lung transplantation.

Objective To study stress relaxation behaviors of cartilage scaffolds under different degradation cycles by using finite element analysis combined with theoretical models. Methods Based on the established degradation theoretical model, the elastic modulus of the scaffold was calculated under different degradation cycles. The finite element model of cartilage scaffolds was established and stress relaxation simulation was performed to analyze the variation of scaffold relaxation stress with time. The stress relaxation constitutive model was established to predict mechanical properties of the scaffold. Results The elastic modulus of cartilage scaffolds at 14 th, 28th, 42nd, 56th day after degradation was 32. 35, 31. 12, 29. 91, 28. 74 kPa, respectively. The upper layer for cartilage scaffolds was the largest. The overall relaxation stress of the scaffold decreased rapidly with time and then tended to be stable. At 8th week after degradation, the stress which the scaffold couldwithstand was still within the physiological load range of the cartilage. The predicted results of the stress relaxation constitutive model were in good agreement with the finite element simulation results. Conclusions The elastic modulus of the scaffold gradually decreases with the increase of degradation time. The longer the degradation period is, the less stress the scaffold can withstand. At the same degradation period, the larger the applied compressive strain, the larger the stress on the scaffold. Both the finite element simulation and stress relaxation constitutive model can effectively predict stress variations of cartilage scaffolds under degradation

Objective:To compare the effect of extracorporeal membrane oxygenation(ECMO)on pulmonary transplantation(LTx)in patients with idiopathic pulmonary fibrosis(IPF)complicated with pulmonary hypertension(PH).Methods:From January 2017 to December 2020, clinical data were retrospectively reviewed for 112 IPF patients complicated with PH undergoing LTx assisted by venous ECMO(VV-ECMO group, n=68)or venous arterial ECMO(VA-ECMO group, n=44). Gender, age, mechanical ventilation time, oxygenation index, cold ischemic time, preoperative gender, age, smoking history, PO 2, PCO 2, PH degree, NYHA cardiac function grade, right cardiac function, ejection fraction(EF)and complications(hypertension & diabetes)of two groups were compared. Intraoperative approach, operative duration, ECMO transfer time, blood loss, blood transfusion, urine volume, postoperative blood transfusion, mechanical ventilation time, ICU stay time, re-thoracotomy, pulmonary infection, primary graft dysfunction(PGD)and renal insufficiency were recorded. And the effects of two different diversion modes on early postoperative complications and short-term outcomes of LTx were further analyzed by multiple factors. Cox proportional risk model was employed for comparing VV-ECMO and VA-ECMO flow patterns with factors related to recipient survival after transplantation. Results:The preoperative PO 2 of 58.3(51.3, 72.0)mmHg was significantly lower in VV-ECMO bypass group than that of 73.2(63.3, 96.8)mmHg in VA-ECMO group and the difference was statistically significant( P<0.006). Compared with VV-ECMO group, 24(54.5%), 15(34.1%)and 22(50.0%)had NYHA class Ⅲ, severe PH and preoperative right heart enlargement in VA-ECMO group respectively and the differences were statistically significant compared with 17(25.0%), 6(8.8%)and 16(23.5%)in VV-ECMO group( P<0.05 for all). No significant inter-group differences existed in postoperative PGD, postoperative mechanical ventilation time(≥3 d), pulmonary infection, postoperative thoracotomy ratio, postoperative renal insufficiency, ICU stay, hospital stay and other aspects( P>0.05). And 6-month postoperative survival rates of VV-ECMO and VA-ECMO groups were 80.9% and 61.4%, respectively and no significant inter-group difference existed in short-term survival rate(6 months)after adjustment by multivariate Cox regression model( P>0.05). Multivariate statistics indicated that the risk of delayed postoperative withdrawal was 14.452-fold higher in VV-ECMO group than in VA-ECMO group and the inter-group difference was statistically significant(95% CI: 2.448-85.323, P=0.03). Conclusions:No differences exist in postoperative complications or short-term survival rate between IPF recipients with mild PH on VV-ECMO mode and IPF recipients with severe PH on VA-ECMO mode. VV-ECMO flow reversal can delay the transplant back-off time.

We reported a 54-year-old female patient with severe tricuspid regurgitation, who received mechanic valve in the mitral position 15 years ago. The patient’s Society of Thoracic Surgeons score was 8.27%, and was intolerant to open heart surgery, so she was recommended for transcatheter tricuspid valve replacement via right vena jugularis interna. The procedures were guided by echocardiography and X ray fluoroscopy on November 13, 2021, the prosthesis was implanted successfully, and the patient was recoved without any adverse events. After 1 month follow-up, her general condition was apparently improved.

Objective    To analyze the etiologies, operation techniques and outcomes of redo aortic root replacement after cardiac surgery. Methods    Between December 2013 and December 2019, 30 patients who had at least one previous cardiac operation received aortic root replacement in our hospital, including 20 males and 10 females with an average age of 50.4±12.7 years. The mean time interval between this operation and the previous one was 8.0±8.5 years. The principal indication for surgery was aortic sinus dilatation and ascending aortic aneurysm in 14 patients (47%), acute aortic dissection in 5 patients (17%), pseudoaneurysm in 3 patients (10%), prosthetic valve endocarditis in 4 patients (13%), prosthetic leakage in 4 patients (13%). Bentall procedure was used in all 30 patients, with concomitant mitral valve plasticity or replacement in 5 patients, tricuspid valve plasticity in 6 patients, coronary artery bypass grafting in 3 patients, and total aortic arch replacement and elephant trunk procedure in 2 patients. Results    The mean cardiopulmonary bypass time was 96-296 (161.3±43.0) min, and the mean aortic occlusion time was 48-117 (85.7±20.4) min. There were 5 in-hospital deaths with an overall in-hospital mortality of 17%. The causes of deaths were low cardiac output syndrome in 2 patients and septic shock in 3 patients. The follow-up time was 3-75 (33.5±21.1) months. Three patients died during the follow-up, 1 patient died of septic shock and 2 died of cerebral hemorrhage. Conclusion    Redo aortic root replacement is difficult to deal with, and the risk is high. Preoperative evaluation is required, appropriate surgical approach, adequate myocardial protection, and a complete surgical plan are essential to ensure the success of the operation.

Objective To investigate whether rat grimace scale (RGS)could be used to assess pain in chronic pancreatitis,so as to provide evidence for pain research and clinical assessment of rat pain.Methods Twenty-eight adult male wister rats were evenly randomized into two groups (n =14):an experimental group and a control group.The experimental group was intravenously given 8 mg/kg body weight dibutyltin dichloride (DBTC)to induce chronic pancreatitis,and the control group was injected with ethanol and glycerin solution.Abdominal hypersensitivity,RGS scores and weight at different time points was detected.HE staining was used to detect the histological changes of pancre-atic tissue.Results Compared with the control group,the rats in the experimental group showed chro-nic inflammation in pancreatic tissue in two weeks.There was a significant increase in the number of abdominal withdrawals (P < 0.001 )and RGS in the experimental group.Conclusion Rat grimace scale might lead to a successful transition of basic science findings into clinical application.

Background Retinal vein occlusion is a common retinal vascular diseases.Thromblysis and anticoagulation therapies are main approaches.However,systemic thrombolysis is relatively inefficient,and it often enhances the risk of hemorrhage.Objective This study was to investigate the therapeutic effects of PLM-ΔK,a kringle deficiency mutant of plasmin,on photochemically induced branch retinal vein occlusion (BRVO) after intravitreal injection.Methods BRVO models were established by the combination of caudal vein injection of Rose Bengal with argon laser radiation of periphery area of retinal veins in SD rats.Forty model rats were randomized into balance salt solution (BSS) group and 0.01 U,0.02 U,0.03 U PLM-ΔK group,and 10 μl corresponding drug was intravtreally injected 12 hours after modeling.Ophthalmoscopy and fundus fluorescein angiography (FFA) were performed to observe the change of retinal veins.The animals were sacrificed 3 days after intravitreal injection,and hematoxylin and eosin staining was used for the histopathological and ultrastructural examination of retinas.The retina of the rats was isolated for the stretched preparation of retina.The expressions of fibronectin (FN) and laminin (LN) in eyeball wall were assayed by immunofluorescence technology.The use and care of the animals complied with Statement of the Association for Research in Vision and Ophthalmology.Results The revascularization of over 2 retinal veins was found in 0,3,6 and 8 rats in the BBS group and 0.01 U,0.02 U,0.03 U PLM-ΔK group 3 days after intravitreal injection,respectively,showing a significant difference among the groups (x2=9.635,P =0.022),and the rat number with revascularization in 0.01 U PLM-ΔK group was not significantly different from that in BSS group (Z=-1.558,P =0.119),but the difference between 0.03 U PLM-ΔK group and 0.01 U PLM-ΔK group was significant (Z=-2.762,P=0.006).In the third day after intravitreal injection,retinal vein thrombus were found in the BSS group under the light microscope,and angiogenesis was seen on the retinal flatmount nuclear.In the 0.03 U PLM-ΔK group,posterior vitreal detachment was exhibited under the light microcope,and no retinal new vessel and cell damage were seen.FN was strongly expressed in the inner limiting membrane (ILM) layer,photocyte layer,outer limiting membrane (OLM) layer,choroid and scleral layer,and LN was expressed mainly in the ILM,OLM and scleral layer in the BSS group.However,the expression intensities of FN and LN were obviously weakened in the 0.03 U PLM-ΔK group.Conclusions Intravitreal injection of PLM-ΔK can enhance the reperfusion of occluded branch retinal vein and serve as a potential therapeutic drug for BRVO.Also it can permeate into choroid after intravitreal injection to degradate FN and LN.

Objective To summarize the results and methods of left subclavian artery revascularization by stented trunk fenestration for acute Stanford type A aortic dissection.Methods Clinical data of 67 patients (54 male and 13 female,mean age of (50 ± 10) years) underwent surgical treatment of left subclavian artery fenestration for acute Stanford A aortic dissection in Department of Cardiothoracic Surgery,Changhai Hospital,Second Military Medical College between September 2008 and December 2014 were analyzed retrospectively.The origin of the left subclavian artery was in the true lumen and no dissection existed near the artery's starting.There were 18 cases of Marfan's syndrome.Preoperative echocardiography showed moderate to severe aortic regurgitation in 10 cases,and mitral regurgitation in 3 cases.Electrocardiogram showed myocardial ischemia in 5 cases.Three patients had acute impaired renal function.All the patients received total arch replacement combined with stented elephant trunk implantation.Left subclavian artery revascularization was performed by stented trunk fenestration as follows:firstly,stented elephant trunk was implanted to completely cover the left subclavian artery,then part of stented trunk's polyester lining was removed which is located at the origin of left subclavian artery.Aortic root procedures included aortic valve replacement in 2 cases,Bentall procedure in 21 cases and aortic valve sparing in 44 cases.Three patients received mitral valve repair and 6 patients received coronary artery bypass grafting.Results The cardiopulmonary bypass time,cross-clamp time,and circulatory arrest time were (179 ± 32) minutes,(112 ± 25) minutes,and (26 ± 10) minutes,respectively.The in-hospital mortality was 7.5％ (5/67):2 patients died of multiple organ failure,1 patient died of acute renal failure and another 2 patients died of severe infection shock.Two patients required reexploration for root bleeding.Transient neurology dysfunction developed in 6 patients.Six patients received tracheotomy and prolonged ventilation due to pulmonary infection.All patients discharged from the hospital were followed up for 1 to 5 years.During long-term follow-up,the survival rate was 100％ and 89.8％ at 1 and 5 years,respectively.CT angiography was performed once per year after discharged.The left subclavian artery perfusion was good.No dissection or anastomosis leakage was identified in any case.Stroke and left limb ischemia did not develope.Conclusion For acute Stanford type A aortic dissection whose origin of the left subclavian artery is in the true lumen and no dissection existed near the artery's starting,the left subclavian artery revascularization by stented trunk fenestration technique during total arch replacement combined with stented elephant trunk implantation is reliable and effective.

Objective To summarize the results and methods of left subclavian artery revascularization by stented trunk fenestration for acute Stanford type A aortic dissection.Methods Clinical data of 67 patients (54 male and 13 female,mean age of (50 ± 10) years) underwent surgical treatment of left subclavian artery fenestration for acute Stanford A aortic dissection in Department of Cardiothoracic Surgery,Changhai Hospital,Second Military Medical College between September 2008 and December 2014 were analyzed retrospectively.The origin of the left subclavian artery was in the true lumen and no dissection existed near the artery's starting.There were 18 cases of Marfan's syndrome.Preoperative echocardiography showed moderate to severe aortic regurgitation in 10 cases,and mitral regurgitation in 3 cases.Electrocardiogram showed myocardial ischemia in 5 cases.Three patients had acute impaired renal function.All the patients received total arch replacement combined with stented elephant trunk implantation.Left subclavian artery revascularization was performed by stented trunk fenestration as follows:firstly,stented elephant trunk was implanted to completely cover the left subclavian artery,then part of stented trunk's polyester lining was removed which is located at the origin of left subclavian artery.Aortic root procedures included aortic valve replacement in 2 cases,Bentall procedure in 21 cases and aortic valve sparing in 44 cases.Three patients received mitral valve repair and 6 patients received coronary artery bypass grafting.Results The cardiopulmonary bypass time,cross-clamp time,and circulatory arrest time were (179 ± 32) minutes,(112 ± 25) minutes,and (26 ± 10) minutes,respectively.The in-hospital mortality was 7.5％ (5/67):2 patients died of multiple organ failure,1 patient died of acute renal failure and another 2 patients died of severe infection shock.Two patients required reexploration for root bleeding.Transient neurology dysfunction developed in 6 patients.Six patients received tracheotomy and prolonged ventilation due to pulmonary infection.All patients discharged from the hospital were followed up for 1 to 5 years.During long-term follow-up,the survival rate was 100％ and 89.8％ at 1 and 5 years,respectively.CT angiography was performed once per year after discharged.The left subclavian artery perfusion was good.No dissection or anastomosis leakage was identified in any case.Stroke and left limb ischemia did not develope.Conclusion For acute Stanford type A aortic dissection whose origin of the left subclavian artery is in the true lumen and no dissection existed near the artery's starting,the left subclavian artery revascularization by stented trunk fenestration technique during total arch replacement combined with stented elephant trunk implantation is reliable and effective.

Objective To investigate whether toll like receptor ( TLR) signaling pathways can in-crease the expression of IL-17 R in neuralglial cells , and if they can whether the increased IL-17 R is func-tional.Methods Experimental autoimmune encephalomyelitis (EAE) was induced in B6 mice by immuni-zation with an emulsion of myelin oligodendrocyte glycoprotein 35-55 ( MOG35-55 ) in complete Freund's adju-vant (CFA).The expression of Il17ra and Il17rc in the brains and spinal cords of mice with EAE were de-tected by real-time PCR.Luxol fast blue ( LFB) staining was performed to the spinal cord sections to detect tissue demyelination.Immunohistological staining against IL-17RA and CD3 were undertook to visualize IL-17RA+and CD3 + cells.Same approaches were also applied to immunized Rag1 -/- mice to figure out whether T cells infiltration is necessary for increasing IL-17RA expression in the central nervous system ( CNS) .Then B6 mice were immunized with incomplete Freund′s adjuvant ( IFA) plus different TLRs ago-nists to measure the expression of Il17ra in the brains and spinal cords by qPCR .The purified astrocytes , microglia and oligodendrocytes isolated from neonatal mice brains were cultured in vitro for two weeks , and then treated with different TLRs agonists .The expression of Il17ra at mRNA and protein levels in the cells were determined by qPCR and Western blot respectively .The astrocytes were treated with IL-17A and LPS individually or in the combination to detect the level of CCL 2, CXCL8 and IP-10 in the supernatant by ELISA.Results B6 mice with induced EAE showed significantly increased Il17ra expressions in the brain and spinal cord , which was also detected in immunized Rag1 -/-mice.Although no spinal cord demyeliza-tion and CD3 cells infiltration were detected in Rag1 -/-mice, significantly increased number of IL-17RA positive cells could still be visualized .In vivo TLRs agonist participated immunization and in vitro treatment of purified neuroglial cells demonstrated that TLRs agonists could directly evoke IL -17RA expression in the CNS or cultured astrocytes , microglia and oligodendrocytes with high efficiency .Both IL-17 A and LPS could stimulate astrocytes to secrete CCL2, CXCL8 and IP-10, however, a combined use of IL-17A and LPS fur-ther augmented the production of these chemokines to a large extend .Conclusion Taken together , we con-cluded that TLRs agonists could directly stimulate neuroglial cells to express IL -17RA which functionally re-spond to IL-17A by secreting chemokines .