Objective:To investigate the potential diagnostic value of peripheral blood soluble programmed cell death protein 1 (sPD-1) and soluble programmed cell death protein ligand 1 (sPD-L1) in acute rejection (AR) following liver transplantation using a rat model.Methods:A rat liver transplantation AR model was established, with the AR group (Lewis→BN) set as the experimental group (n=6) and the non-AR group (BN→BN) as the control group (n=6). Peripheral blood sPD-1 and sPD-L1 concentrations were measured using enzyme-linked immunosorbent assay (ELISA) at 1 day before transplantation and at 1, 3, and 7 days postoperatively. On postoperative day 7, the expression levels of PD-1 and PD-L1 in liver tissues were detected by immunohistochemistry (IHC). Independent samples t-test and repeated measures ANOVA were used to compare the results between the two groups. Pearson correlation analysis was conducted to evaluate the relationship between sPD-1, sPD-L1, the sPD-1/sPD-L1 ratio, and the rejection activity index.Results:On postoperative day 7, the experimental group exhibited significantly higher peripheral sPD-1 levels (218.59±36.88 vs. 164.95±15.82 ng/L) and a higher sPD-1/sPD-L1 ratio (0.44±0.12 vs. 0.36±0.07), but lower sPD-L1 levels (379.56±73.41 vs. 423.64±96.55 ng/L) compared to the control group (all P<0.05). Correlation analysis revealed a significant positive correlation between sPD-1 levels and the rejection activity index ( r=0.680, P<0.05), as well as between the sPD-1/sPD-L1 ratio and the rejection activity index ( r=0.795, P<0.01), while no correlation was observed between sPD-L1 levels and the rejection activity index. IHC demonstrated positive PD-1 and PD-L1 expression in the liver tissues of the experimental group, whereas the control group showed negative expression. Conclusion:Peripheral blood sPD-1 levels and the sPD-1/sPD-L1 ratio are significantly associated with AR after liver transplantation in rats, suggesting their potential as biomarkers for diagnosing AR in liver transplant recipients.

Objective:To investigate the potential diagnostic value of peripheral blood soluble programmed cell death protein 1 (sPD-1) and soluble programmed cell death protein ligand 1 (sPD-L1) in acute rejection (AR) following liver transplantation using a rat model.Methods:A rat liver transplantation AR model was established, with the AR group (Lewis→BN) set as the experimental group (n=6) and the non-AR group (BN→BN) as the control group (n=6). Peripheral blood sPD-1 and sPD-L1 concentrations were measured using enzyme-linked immunosorbent assay (ELISA) at 1 day before transplantation and at 1, 3, and 7 days postoperatively. On postoperative day 7, the expression levels of PD-1 and PD-L1 in liver tissues were detected by immunohistochemistry (IHC). Independent samples t-test and repeated measures ANOVA were used to compare the results between the two groups. Pearson correlation analysis was conducted to evaluate the relationship between sPD-1, sPD-L1, the sPD-1/sPD-L1 ratio, and the rejection activity index.Results:On postoperative day 7, the experimental group exhibited significantly higher peripheral sPD-1 levels (218.59±36.88 vs. 164.95±15.82 ng/L) and a higher sPD-1/sPD-L1 ratio (0.44±0.12 vs. 0.36±0.07), but lower sPD-L1 levels (379.56±73.41 vs. 423.64±96.55 ng/L) compared to the control group (all P<0.05). Correlation analysis revealed a significant positive correlation between sPD-1 levels and the rejection activity index ( r=0.680, P<0.05), as well as between the sPD-1/sPD-L1 ratio and the rejection activity index ( r=0.795, P<0.01), while no correlation was observed between sPD-L1 levels and the rejection activity index. IHC demonstrated positive PD-1 and PD-L1 expression in the liver tissues of the experimental group, whereas the control group showed negative expression. Conclusion:Peripheral blood sPD-1 levels and the sPD-1/sPD-L1 ratio are significantly associated with AR after liver transplantation in rats, suggesting their potential as biomarkers for diagnosing AR in liver transplant recipients.

Objective:To explore the feasibility and safety of robotic-assisted living donor left lateral segmentectomy (LDLLS) in a large pediatric liver transplant program.Methods:Retrospective analysis was performed for clinical data of 45 LDLLS donors and recipients from June 2021 to September 2022.Traditional open donor liver resection (n=30) and robotic-assisted segmentectomy (n=15) were performed.Two groups were compared with regards to operative duration, intraoperative hemorrhage, postoperative healing and postoperative complications.SPSS 21.0 was utilized for statistical analysis.Independent sample T, paired sample T, Wilcoxon rank sum and Chi-square tests were performed for examining the inter-group differences.Results:Operative duration of robot-assisted surgery group was substantially longer than that of traditional open surgery group ( P<0.001). Intraoperative blood loss was less in robot-assisted surgery group was less than that in traditional open surgery group[(106.0±39.8) vs.(251.0±144.8) ml, P=0.001]. Postoperative hospital stay of robot-assisted surgery group was shorter than that of traditional open surgery group[6.0(6.0, 6.0) vs.7.0(6.0, 9.0), P<0.05]. Two cases of postoperative biliary leakage were observed in donor of traditional open surgery group.Among 2 cases of abdominal infection, one was due to biliary leakage from liver section and secondary surgery was then performed.One case of incisional infection and another case of thrombosis occurred in donor of traditional open surgery group.In robot-assisted surgery group, only one donor had amylase elevation.In traditional open surgery group, there were one case of local thrombosis in middle hepatic vein and one case of bile duct stricture.No long-term complications occurred in robot-assisted surgery group during a follow-up period of over 6 months.Finally recipient data analysis indicated that no significant inter-group differences existed in operative duration, intraoperative blood loss, postoperative hospital stay or postoperative abdominal infection ( P=0.634, P=0.180, P=0.86 and P=0.153). Conclusions:Robotic-assisted LDLLS proves to be be a safe and reliable option for living donor segmentectomy.It is superior to conventional LDLLS in terms of shorter hospital stay, less intraoperative blood loss and fewer postoperative complications.

Objective To evaluate the role of preoperative serological indexes in predicting long-term survival and tumor recurrence of hepatocellular carcinoma (HCC) patients after liver transplantation, aiming to explore its significance in expanding the Milan criteria. Methods Clinical data of 669 recipients undergoing liver transplantation for HCC were retrospectively analyzed. The optimal cut-off value was calculated by the receiver operating characteristic (ROC) curve. The risk factors affecting the overall survival and recurrence-free survival rates of HCC patients after liver transplantation were identified by univariate and multivariate regression analyses. The correlation between preoperative serum liver enzymes and pathological characteristics in HCC patients was analyzed. The predictive values of alpha-fetoprotein (AFP) combined with γ -glutamyl transferase (GGT) and different liver transplant criteria for the survival and recurrence of HCC patients after liver transplantation were compared. Results Exceeded Milan criteria, total tumor diameter (TTD) > 8 cm, AFP > 200 ng/mL and GGT > 84 U/L were the independent risk factors for the overall survival and recurrence-free survival rates of HCC patients after liver transplantation (all P < 0.05). Correlation analysis showed that preoperative serum GGT level was correlated with TTD, number of tumor, venous invasion, microsatellite lesions, capsular invasion, tumor, node, metastasis (TNM) stage, Child-Pugh score and exceeded Milan criteria (all P < 0.05). Milan-AFP-GGT-TTD (M-AGT) criteria were proposed by combining Milan criteria, TTD with serum liver enzyme indexes (AFP and GGT). The 5-year overall survival and recurrence-free survival rates of HCC recipients who met the M-AGT criteria (111 cases of exceeded Milan criteria) were significantly higher than those who met Hangzhou criteria (both P < 0.05), whereas had no significant difference from their counterparts who met the University of California at San Francisco (UCSF) criteria (both P > 0.05). Conclusions Preoperative serological indexes of AFP and GGT could effectively predict the long-term survival and tumor recurrence of HCC patients after liver transplantation. Establishing the M-AGT criteria based on serological indexes contributes to expanding the Milan criteria, which is convenient and feasible.

Objective:To explore the pathogenesis and prognostic factors of brain metastasis of hepatocellular carcinoma(HCC)after liver transplantation(LT).Methods:Retrospective review was performed for 17 HCC cases with brain metastasis after liver transplantation from 2000 to 2020.All cases were diagnosed as hepatitis B cirrhosis complicated with HCC.All of them were beyond the Milan Criteria.The immunosuppressive regimen consisted of baliximab + mycophenolate mofetil + calcineurin inhibitors(CNIs)+ corticosteroids in early postoperative period with a gradual tapering of corticosteroids and mycophenolate mofetil.Three patients received sirolimus immunotherapy after tumor recurrence and withdrew CNIs.One of three cases received sorafenib.Results:Other organ involvements included lung metastasis( n=16, 94.1%), bone metastasis( n=5, 29.4%)and liver metastasis( n=6, 35.3%). The median survival time after brain metastasis was 7 months and the 1-year cumulative survival rate 29.4%.The median survival time post-LT was 14 months and the 1-year cumulative survival rate 64.7%.Among 7 patients with a resection of brain metastasis, two deaths at Month 1 post-operation were due to cerebral hemorrhage.The longest survival time was 214 months and the median survival time 9 months. Conclusions:The prognosis of brain metastasis post-LT remains poor.However, early detection and reasonable treatment can prolong patient survival time and even achieve long-term survival.Most brain metastases are accompanied by lung metastases.And the finding of lung metastatic tumor hints at a presence of intracranial lesions.

Objective:To investigate the etiology,clinical features and prognosis of pediatric liver retransplantation.Methods:The data of 1 024 cases of pediatric liver transplantation (<18 years old) from January 2014 to December 2019 operated at Tianjin First Central Hospital were collected,retrospectively. Retransplantation was performed in 26 cases,among which 25 cases received secondary liver transplantation and 1 case received a third liver transplantation. There were 13 male and 12 female patients among the 25 patients. The median age was 12.9(20.5) months(range: 5.8 to 134.8 months), the body weight was 8.0(5.6) kg(range: 5.0 to 30.0 kg) at the time of retransplantation. The pediatric end-stage liver disease(PELD) score was 17.0(21.3) (range: 0 to 45) before retransplantation. The etiology of retransplantation was biliary complications in 7 cases,primary nonfunction of liver graft in 5 cases,antibody-mediated rejection in 4 cases,hepatic artery thrombosis in 3 cases,portal vein thrombosis in 3 cases,concomitant hepatic artery and portal vein thrombosis in 2 cases,thrombogenesis of inferior Vena Cava in 1 case and sinusoidal obstruction syndrome in 1 case. The patients were divided into two groups according to the time interval(30 days) between two liver transplantations,8 patients were classified into early-retransplantation(≤30 days) group and 18 patients were classified into late-retransplantation (>30 days) group. The etiology of liver retransplantation,pre-transplant score,time interval between two transplantations,surgical aspects,major complications and survival rates were compared between the two groups. Continuous variables with normal distribution were compared with t test,while Mann-Whitney U test was applied to compare variables without normal distribution. Categorical variables were compared with chi-square test. The survival curves were created by Kaplan-Meier method and compared by Log Rank test. Results:The median follow-up time was 26.8(30.2) months(range: 1 day to 85.7 months), and the incidence of retransplantation was 1.9%. In the early-retransplantation group,the duration of surgery was (439.8±151.0)minutes,the graft-to-recipient weight ratio was 5.0(1.8)%(range:3.6% to 6.1%),the main cause for retransplantation were primary nonfunction and vascular complications. In the late-retransplantation group,the duration of surgery was (604.4±158.0)minutes,the graft-to-recipient weight ratio was 3.4(2.1)%(range:1.4% to 5.3%),the main cause for retransplantation were biliary complications,antibody mediated rejection and vascular complications.The 3-month,1-year and 2-year recipient survival rates in the early-retransplantation group were all 62.3%,while the recipient survival rates in the late-retransplantation group were 100%,93.8% and 93.8%,respectively. The difference of recipient survival rates was significant between the early-retransplantation group and the late-retransplantation group( P=0.019). The overall 3-month,1-year and 3-year recipient survival rates after the primary liver transplantation were 97.1%,95.4%,94.1%,respectively. Conclusions:The vascular complications,biliary complications,primary nonfunction and antibody-mediated rejection are the main causes of liver retransplantation.The PELD score is higher in patients receiving early retransplantation,while the surgery is relatively more complex in patients receiving late retransplantation,which is reflected by longer duration of surgeries. Patients in the late-retransplantation group showed similar recipient survival rates with primary liver transplantation recipients,and the survival rates are superior to those of patients in the early-retransplantation group. Infection and multiple organ failure are the most common fatal causes after retransplantation.

Objective:To explore the clinicalfactors related to allograft fibrosis after pediatric liver transplantation.Methods:The clinical data were respectively analyzed for 94 pediatric recipients from January 2013 to December 2016 at Tianjin First Central Hospital.The Patients were assigned into fibrotic and non-fibrotic groups based upon the results of protocol liver biopsies. Univariate and multivariate Logistic regression analyses were performed for examining the risk factors of fibrosis after pediatric livertransplantation. Then Logistic regression model was established to obtain the predicted value of combined predictive factors.Thereceiver operating characteristic curve (ROC) was conducted to evaluate the predictive value of combined predictive factors.Results:A total number of 54(57.5%) patients occurred fibrosis among the 94 patients. There weresignificant differences in cold ischemia time (Z=2.094), warm ischemia time (Z=2.421), biliary stricture( χ2=4.560), drug-induced liver injury ( χ2=7.389), hepatic artery thrombosis and rejection ( χ2=6.955)between two groups ( P<0.05). Logistic regression analysis showed that cold ischemia time (OR=1.003, 95%CI: 1.000~1.007, P=0.044), biliary stricture(OR=6.451, 95%CI: 1.205~33.295), rejection(OR=2.735, 95%CI: 1.057~7.077)and drug-induced liver injury (OR=4.977, 95%CI: 1.207~20.522, P=0.026) were independent risk factors for fibrosis 5 years after liver transplantation. The area under the ROC curve was 0.786(95%CI: 0.691~0.881), for predicting patient outcome.If using 0.311as a cutoff Value, the sensitivity was 90.70%, and the specificity was 60.00%. However, through the ROC curve comparison, there was statistical significance between combined predictive factors and the other independent risk factors ( P>0.05). Conclusions:The incidence of fibrosis 5 years after pediatricliver transplantation is 57.5%. Prolonged cold ischemia time, biliarystricture, rejectionand drug-induced liver injury after liver transplantation are independent risk factors for fibrosis 5 years after pediatric liver transplantation.And the combined predictive factors have a high predictive value forallograftfibrosis.

Objective:To investigate the etiology,clinical features and prognosis of pediatric liver retransplantation.Methods:The data of 1 024 cases of pediatric liver transplantation (<18 years old) from January 2014 to December 2019 operated at Tianjin First Central Hospital were collected,retrospectively. Retransplantation was performed in 26 cases,among which 25 cases received secondary liver transplantation and 1 case received a third liver transplantation. There were 13 male and 12 female patients among the 25 patients. The median age was 12.9(20.5) months(range: 5.8 to 134.8 months), the body weight was 8.0(5.6) kg(range: 5.0 to 30.0 kg) at the time of retransplantation. The pediatric end-stage liver disease(PELD) score was 17.0(21.3) (range: 0 to 45) before retransplantation. The etiology of retransplantation was biliary complications in 7 cases,primary nonfunction of liver graft in 5 cases,antibody-mediated rejection in 4 cases,hepatic artery thrombosis in 3 cases,portal vein thrombosis in 3 cases,concomitant hepatic artery and portal vein thrombosis in 2 cases,thrombogenesis of inferior Vena Cava in 1 case and sinusoidal obstruction syndrome in 1 case. The patients were divided into two groups according to the time interval(30 days) between two liver transplantations,8 patients were classified into early-retransplantation(≤30 days) group and 18 patients were classified into late-retransplantation (>30 days) group. The etiology of liver retransplantation,pre-transplant score,time interval between two transplantations,surgical aspects,major complications and survival rates were compared between the two groups. Continuous variables with normal distribution were compared with t test,while Mann-Whitney U test was applied to compare variables without normal distribution. Categorical variables were compared with chi-square test. The survival curves were created by Kaplan-Meier method and compared by Log Rank test. Results:The median follow-up time was 26.8(30.2) months(range: 1 day to 85.7 months), and the incidence of retransplantation was 1.9%. In the early-retransplantation group,the duration of surgery was (439.8±151.0)minutes,the graft-to-recipient weight ratio was 5.0(1.8)%(range:3.6% to 6.1%),the main cause for retransplantation were primary nonfunction and vascular complications. In the late-retransplantation group,the duration of surgery was (604.4±158.0)minutes,the graft-to-recipient weight ratio was 3.4(2.1)%(range:1.4% to 5.3%),the main cause for retransplantation were biliary complications,antibody mediated rejection and vascular complications.The 3-month,1-year and 2-year recipient survival rates in the early-retransplantation group were all 62.3%,while the recipient survival rates in the late-retransplantation group were 100%,93.8% and 93.8%,respectively. The difference of recipient survival rates was significant between the early-retransplantation group and the late-retransplantation group( P=0.019). The overall 3-month,1-year and 3-year recipient survival rates after the primary liver transplantation were 97.1%,95.4%,94.1%,respectively. Conclusions:The vascular complications,biliary complications,primary nonfunction and antibody-mediated rejection are the main causes of liver retransplantation.The PELD score is higher in patients receiving early retransplantation,while the surgery is relatively more complex in patients receiving late retransplantation,which is reflected by longer duration of surgeries. Patients in the late-retransplantation group showed similar recipient survival rates with primary liver transplantation recipients,and the survival rates are superior to those of patients in the early-retransplantation group. Infection and multiple organ failure are the most common fatal causes after retransplantation.

Lycopene, as a high value-added terpene compound, has been widely concerned by researchers at home and abroad. Firstly, the ability of lycopene synthesis of Saccharomyces cerevisiae model strains S288c and YPH499 was analyzed and compared. The results showed that YPH499 was more suitable for lycopene synthesis as yeast chassis. Subsequently, the effects of constitutive promoters GPDpr, TEF1pr and inducible promoters GAL1pr, GAL10pr on Lycopene synthesis were compared. The results showed that when GPDpr and TEF1pr were used as promoters of crtE, crtB and crtI in lycopene synthesis pathway, the production of lycopene was 15.31 mg/L after 60 h fermentation in shaking flask. When GAL1pr and GAL10pr were used as promoters, the production was 123.89 mg/L, which was 8.09 times higher. In addition, the methylvaleric acid (MVA) pathway was further modified to overexpress the key enzyme gene of N-terminal truncation, tHMG1 (3-hydroxy-3-methylglutaryl coenzyme A reductase). The lycopene production was 265.68 mg/L, and the yield per cell was 72.79 mg/g. The Saccharomyces cerevisiae strain designed and constructed in this study can express lycopene in high yield per cell, thus could be used in the industrial production of lycopene after further construction and optimization.
Biosynthetic Pathways ; genetics ; Fermentation ; Industrial Microbiology ; Lycopene ; metabolism ; Saccharomyces cerevisiae ; genetics ; metabolism ; Species Specificity

Objective To summarize the experiences of diagnosing and treating portal vein stenosis (PVS) after pediatric liver transplantation from China donation after citizen 's death (CDCD) grafts .Methods Retrospective analysis was performed for 30 cases of pediatric CDCD liver transplantation recipients with PVS .The screening ,diagnosis ,treatment and prognosis of PVS were analyzed .Results Among 218 pediatric liver transplantation recipients with CDCD grafts ,PVS was diagnosed in 30 cases with an incidence rate of 13 .8％ (30/218) .The initial diagnosis of PVS ranged from 5 days to 27 months post-operation with a median age of 2 .9 months .Ultrasonography indicated that stenotic rate of anastomotic site diameter was (41 .28 ± 12 .93)％ and blood flow velocity ratio (358 .77 ± 117 .82)％ .Intervention examination showed average pressure gradient was (9 .06 ± 5 .34) mmHg between both sides of stenosis . All cases underwent percutaneous intrahepatic balloon dilatation .The recipients were followed up for a median follow-up time of 23(3-63) months .For three cases of restenosis ,percutaneous intrahepatic balloon dilatation was repeated .Two cases underwent stent implantation due to ineffective balloon dilation .After treatment ,the stenotic rate of anastomotic site diameter was (34 .69 ± 8 .82) and blood flow velocity ratio (61 .18 ± 63 .11)％ on ultrasound while the average pressure gradient was (1 .03 ± 0 .85) mmHg .Conclusions PVS is a common vascular complication after pediatric CDCD liver transplantation .Portal vein balloon dilation is both safe and efficacious .However ,some cases require repeated balloon dilation and stent implantation serves as the last option for intractable PVS .Color ultrasound is both convenient and effective for making a primary diagnosis and evaluating outcomes .