Microbial transformation of (±)-6-(1,1-dimethylallyl)naringenin (6-DMAN, 1) and (±)-5-(O-prenyl) naringenin-4′,7-diacetate (5-O-PN, 2) was performed by using fungi. Scale-up fermentation studies with Mucor hiemalis, Cunninghamella elegans var. elegans, and Penicillium chrysogenum led to the isolation of five microbial metabolites. Chemical structures of the metabolites were determined by spectral analyses as (±)-8-prenylnaringenin (3), (2S)-5,4′-dihydroxy-7,8-[(R)-2-(1-hydroxy-1-methylethyl)-2,3-dihydrofurano]flavanone (4), (±)-5-(O-prenyl)naringenin-4′-acetate (5), (±)-naringenin-4′-acetate (6), and (±)-naringenin (7), of which 5 was identified as a new compound.
Cunninghamella ; Fermentation ; Fungi ; Mucor ; Penicillium chrysogenum

Objective To evaluate the feasibility and safety of using pediatric donation after brain death donors during split liver transplantation .Methods The clinical data were retrospectively reviewed for 8 pediatric recipients undergoing split liver transplantation with a donor age of 2 .7-7 years .The clinical characteristics of donors/recipients ,perioperative course ,postoperative recovery and complications along with graft and recipient survival rate were analyzed .Results The split procedure was performed ex situ (n=3) and in situ (n=1) ,all liver grafts were split into left lateral lobes and extended right lobes . The recipients were children aged 4 .7-105 .5 months . The mean follow-up period was (8 .1 ± 0 .6) months and the graft/recipient survival rates approached 100％ . Graft functions remained normal in all recipients at the end of follow-ups .Two recipients undergoing liver grafting with long cold ischemia time exhibited slower recovery of graft function .Pathological examination of graft biopsy indicated ischemic and hypoxic changes .Portal vein stenosis occurred in one recipient .Percutaneous transhepatic portal vein balloon dilatation was performed and the recipient recovered well .Cytomegalovirus infection occurred in 5/8 recipients and serum virological marker returned to normal after ganciclovir therapy . The youngest donor age was 2 .7 years and both recipients of donor liver recovered well .Conclusions Split liver transplantation with a donor age of 2 .7-7 .0 years may achieve ideal clinical outcomes in well-matched donors and recipients .

Objective To explore the clinical efficacy of pediatric blood type incompatible living donor liver transplantation. Methods The clinical data from 242 cases of pediatric living donor liver transplantation recipients were retrospectively analyzed. Recipients were assigned to group A (ABO-identical group, n=165), group B (ABO-compatible group, n=42) and group C (ABO-incompatible group, n=35) according to the blood type compatibility between the recipients and the donors. The occurrence of postoperative complications and development of postoperative donor specific antibody (DSA) among the 3 groups were observed and compared. And the blood type distribution of donors and recipients and development of erythrocyte antibodies in group C were analyzed. The survival situation of recipients after liver transplantation was compared among the 3 groups. Results There was no significant difference in the incidence of complications among the 3 groups(all P > 0.05). DSA was dominated by human leukocyte antigen (HLA) Ⅱ antibodies after liver transplantation, mostly anti-HLA-DR and anti-HLA-DQ. The postoperative erythrocyte antibodies for liver transplant recipients in group C were dominated by IgM, with titers ≤1:2 for all. The differences in postoperative survival rates were not statistically significant among 3 groups(all P > 0.05). Conclusions Pediatric blood type incompatible living donor liver transplantation is a safe and effective treatment, which can effectively expand the source of liver transplant donors and save the children's lives.

Objective:To explore the relationship between serum lactate level and early prognosis after liver transplantation (LT) in children.Methods:Between January 1, 2018 and December 31, 2020, 675 pediatric LT recipients were recruited. Clinical data were retrospectively reviewed, early postoperative serum lactate level and clearance rate recorded and receiver operating characteristic (ROC) curve plotted for determining optimal cut-off values. The inter-group differences in early postoperative complications and patient/graft survival rates were compared.Results:According to ROC, blood lactate levels >1.99 mmol/L at 12 h postoperatively were associated with early postoperative graft loss (AUC 0.73, 95% CI: 0.62-0.84, P=0.01). Age and weight of recipients in high-level group were 7.17(5.70-10.40) month and 7.00(6.00-8.60) kg and both were significantly lower than those in low-level group [7.80(6.21-13.58) month and 7.20(6.45-9.00) kg]. The inter-group differences were statistically significant ( P=0.017, P=0.034). Blood plasma transfusion volume, red blood cell transfusion volume, portal vein pressure pre-closure, postoperative intensive care unit (ICU) stay, ventilator use time, early allograft dysfunction rate, early postoperative pulmonary infection rate and recipient mortality rate in high-level group were 400 (200-400) ml, 2.00 (2.00-4.00) U, (15.71±4.44) mmHg, 2.50(2.00-3.00) day, 3.81(2.47-8.50) hour, 22.95%(42/185), 16.76%(31/185) and 6.49%(12/185) respectively. The above values were significantly higher than those in low-level group 200(100-400) ml, 2.00 (2.00-3.00) U, (14.69±4.68) mmHg, 2.00(2.00-3.00) day, 3.53(2.34-6.12) hour, 14.69%(72/490), 11.02%(54/490) and 1.43%(7/490) respectively. The inter-group differences were statistically significant ( P<0.001, P=0.014, P=0.015, P=0.037, P=0.043, P=0.011, P=0.045 & P<0.001). The incidence of early postoperative acute cellular rejection was significantly lower in high-level group than that in low-level group [11.89%(22/185) vs 22.86%(112/490)]. The inter-group difference was statistically significant ( P=0.01). The 1/3-month cumulative survival rates of patient/graft were 94.6%, 94.1% and 92.4%, 91.4% in high-level group versus 99.2%, 98.6% and 99.0%, 98.4% in low-level group. There were significant inter-group differences ( P=0, P<0.000 1). With a rising level of lactate at 12 h postoperatively, risk of early graft loss and early recipient mortality spiked markedly ( P<0.05). Conclusions:Serum lactate level post-operation is a valid predictor of early prognosis after LT in children.

Objective:To explore the impact of graft recipient weight ratio(GRWR)on pediatric whole liver transplantation in infants aged under 1 year.Methods:From January 2014 to December 2019, clinical data were retrospectively reviewed for 140 children aged under 1 year with whole liver transplantation.They were divided into 3 groups of low GRWR(GRWR<2.5%, 48 cases), middle GRWR(2.5%≤GRWR<5%, 73 cases)and high GRWR(GRWR≥5%, 19 cases). Basic profiles, major postoperative complications and survival rate of graft/recipient were compared.Results:There were 62 males and 78 females with an average age of (7.34±1.81)months and an average weight of(6.81±1.09)kg.The median GRWR was 3.27%(1.33%~8.12%). The higher level of GRWR, the greater age, weight and graft weight of donor in three groups and there was statistical difference ( P<0.05); operative duration, postoperative ICU stay and hospital stay were longer in low GRWR group than those in middle GRWR group and there was statistical difference( P<0.05); The incidence of postoperative hepatic artery thrombosis was higher in low GRWR group than that in middle GRWR group(31.3%vs 8.2%)and there was statistical difference( P<0.05); 4 cases of small-for-size syndrome occurred in low GRWR group, it was significantly different from the other two groups and there was statistical difference( P<0.05); the median follow-up period was(50.7±23.4)months.The survival rates of grafts at 3-month and 1/5-year were 89.6%, 91.8%, 100%; 87.5%, 87.7%, 100%; 87.5%, 87.7%, 100%and there was no inter-group difference( P>0.05). The survival rates of recipients at 3 months, 1 year and 5 years post-operation were 93.8%, 91.8%, 100%; 91.7%, 87.7%, 100%; 91.7%, 87.7%, 100%and there was no inter-group difference( P>0.05). Conclusions:Different from pediatric living donor transplantation, GRWR≥5%does not affect the survival rate of recipient/graft during whole liver transplantation.And GRWR<2.5%may boost the postoperative incidence of hepatic artery thrombosis and small liver syndrome.

Objective:To explore the preventive efficacy of 2-week ganciclovir intravenous injection for CMV infection after pediatric liver transplantation(LT).Methods:Clinical data were retrospectively analyzed for 404 pediatric LT recipients from January 1, 2015 to December 31, 2017. According to whether or not ganciclovir was intravenously administered for preventing CMV infection, they were divided into two groups of prevention(235 cases)and non-prevention(169 cases). The preoperative, intraoperative and postoperative follow-up data of two groups were recorded. Survival rate, incidence of CMV infection and time of initial CMV infection were compared between two groups.Results:The median follow-up time of 404 pediatric liver transplantation recipients was 856 days and the incidence of CMV infection 39.1%. No inter-group statistical difference existed in such basic clinical data as gender, age, primary disease, preoperative PELD score, CHILD grade, operative duration, intraoperative blood loss, immunosuppressive regimen or rejection rate. The median follow-up time of two groups was 1014 and 731 days; The incidence of CMV infection 37.4%(88/235)and 41.4%(70/169); The average postoperative time of initial CMV infection 75.5 and 110.2 days; The rate of CMV re-infection after initial CMV infection 26.1%(23/88)and 18.6%(13/70)respectively. No significant inter-group differences existed( P>0.05). Conclusions:Early postoperative 2-week intravenous ganciclovir injection fails to reduce the incidence of CMV infection after pediatric LT, nor delay the occurrence time of CMV infection. It is not recommended as a preventive program for CMV infection after pediatric LT.

Objective:To examine the incidence of lymphatic leakage after pediatric liver transplantation and explore the diagnosis and treatment of lymphatic leakage.Methods:From January 1, 2016 to December 31, 2019, clinical data were analyzed retrospectively for 805 pediatric liver transplant recipients. Based upon the diagnosis of lymphatic leakage, they were divided into two groups of lymphatic leakage ( n=271) and lymphatic non-leakage ( n=534). Analyzing the incidence of lymphatic leakage after liver transplantation in children, evaluating the treatment plan, comparing survival rate and the incidence of postoperative complications between two groups. Results:The incidence of lymphatic leakage was 33.7%(271/805); the proportion of partial liver donors was 14.8% in lymphatic leakage group and 25.8% in lymphatic non-leakage group ( P<0.001). Other basic profiles of two groups were not statistically different. The median follow-up period was 32 months in lymphatic leakage group and 30.6 months in lymphatic non-leakage group. No significant inter-group difference existed in cumulative survival rate, vascular complications, bile leakage, acute cell rejection or intestinal obstruction. The area-under-curve (AUC) of ascites to serum triglyceride (TG) ratio for predicting lymphatic leakage was 0.741, optimal cut-off value 0.54, sensitivity 59.2% and specificity 80.1%. Conclusions:Lymphatic leakage is a common complication after liver transplantation in children. With no significant correlation with the morbidity or mortality, it prolongs postoperative hospital stay. The ratio of ascites to serum TG may be utilized as an effective reference index for diagnosing lymphatic leakage. And lymphatic leakage can be improved by taking a low-fat diet.

Objective:To explore the efficacy of reduced left lateral segment graft during pediatric living donor liver transplantation.Methods:From January 2014 to December 2019, 67 children aged under 1 year underwent living donor liver transplantation with reduced left lateral segment graft (RLLS group). Clinical data were analyzed retrospectively and compared with those of left lateral segmentgraft living donor liver transplantation (LLS group). The differences in basic profiles, postoperative complications and postoperative patient/graft survival rate were compared.They were divided into two groups according to whether graft/recipient weight ratio (GRWR) was more than 4%.And major postoperative complications and graft/recipient survival rates were compared.Results:Age, height and weight of recipients were significantly lower in RLLS group than those in control group ( P<0.05). However, donor weight, donor body mass index (BMI), estimated graft volume and proportion of fatty liver from donor were significantly higher than those in control group ( P<0.05). Operative duration, intraoperative blood loss and erythrocyte transfusion were significantly higher than those in control group ( P<0.05). No significant inter-group differences existed in average postoperative hospital stay, intensive care unit (ICU) stay duration or postoperative ventilator use time ( P>0.05); no significant inter-group difference existed in the incidence of such major surgical complications as hepatic artery thrombosis, portal vein stenosis and bile duct complications ( P>0.05). The 1/3-year cumulative survival rates of postoperative patients and grafts were 92.5%, 91.2% and 92.5%, 91.2% in RLLS group and 96.3%, 95.3% and 95.9%, 95.1% in LLS group respectively.There was no significant inter-group difference ( P<0.05). The rate of postoperative hepatic vein stenosis was significantly higher in GRWR>4% group than that in control group ( P<0.05). Conclusions:Due to a rapid progress of technology, living donor liver transplantation has achieved satisfactory outcomes in children with reduced left lateral segment graft.Whether or not performing reduction surgery should be judged comprehensively according to the matching of donors and recipients and blood flow of liver during operations.And GRWR>4% is not an implementation criterion.

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 study the impact of donor left hepatic vein classification and the reconstruction methods on hepatic venous outflow obstruction (HVOO) after pediatric living-donor liver transplantation using left lateral liver segments.Methods:A retrospective study was performed on the clinical data of 653 children recipients who underwent living-donor liver transplantation with left lateral liver segments from January 2014 to December 2020 at Tianjin First Central Hospital. There were 309 males and 344 females, aged 7.0 (6.0, 10.0) months, with an age range of 3-121 months. Based on the left hepatic vein on preoperative donor enhancement CT as well as the intraoperative reconstruction methods, the recipients were divided into 3 groups: type Ⅰ group ( n=514), anastomosis using a single opening was performed directly between the donor and the recipient; type Ⅱ group ( n=118), angioplasty was performed on two adjacent recipient venous orifices before anastomosis, and type Ⅲ group ( n=21), an interposition vessel was anastomosed to two widely spaced openings or the two veins were anastomosed separately. The preoperative general status of the patient, postoperative HVOO incidences, and graft and recipient survival rates were compared among the three groups. The patients were followed up by outpatient reexamination or telephone. Results:Graft to recipient weight ratio in the type Ⅲ group was smaller than that in the type Ⅰ group and the type Ⅱ group ( P<0.05). For all the 653 patients, the incidence of postoperative HVOO was 4.59% (30/653), with the incidences of HVOO in the 3 groups of patients were 4.1% for the type Ⅰ group (21/514), 5.1% for the type Ⅱ group (6/118), and 14.3% for the type Ⅲ group (3/21), respectively. There was no significant difference among the groups ( P>0.05). The recipient cumulative survival rates at 1 and 3 years after surgery in the type I group were 97.8% and 97.0%, and the corresponding rates in the type Ⅱ group were 96.5% and 94.2%, and in the type Ⅲ group were 94.1% and 86.9%, respectively. There was a significant difference between the type Ⅰ and type Ⅲ groups ( P=0.048). The graft cumulative survival rates at 1 and 3 years in the type Ⅰ group were 97.4% and 96.9%, and the corresponding rates in the type Ⅱ group were 94.9% and 92.5%, and in the type Ⅲ group were 94.1% and 86.9%, respectively. The difference in the postoperative graft cumulative survival rates between the type Ⅰ group and type Ⅱ group was significant ( P=0.044). Conclusions:The anatomy of the left hepatic vein supplying the left lateral liver segment was highly variable, and the majority of the variations could be reconstructed. A reasonable reconstructive method could reduce the incidence of postoperative HVOO and improved the outcomes of the graft.