Population pharmacokinetics and limited sampling strategies of polymyxin B in critically ill patients

OBJECTIVES

To characterize the pharmacokinetics (PK) of polymyxin B in Chinese critically ill patients. The factors significantly affecting PK parameters are identified, and a limited sampling strategy for therapeutic drug monitoring of polymyxin B is explored.

METHODS

Thirty patients (212 samples) were included in a population PK analysis. A limited sampling strategy was developed using Bayesian estimation, multiple linear regression and modified integral equations. Non-linear mixed-effects models were developed using Phoenix NLME software.

RESULTS

A two-compartment population PK model was used to describe polymyxin B PK. Population estimates of the volumes of central compartment distribution (V) and peripheral compartment distribution (V2), central compartment clearance (CL) and intercompartmental clearance (Q) were 7.857 L, 12.668 L, 1.672 L/h and 7.009 L/h. Continuous renal replacement therapy (CRRT) significantly affected CL, and body weight significantly affected CL and Q. The AUC0-12h of polymyxin B in patients with CRRT was significantly lower than in patients without CRRT. CL and Q increased with increasing body weight. A limited sampling strategy was suggested using a two-sample scheme with plasma at 0.5h and 8h after the end of infusion (C0.5 and C8) for therapeutic drug monitoring in the clinic.

CONCLUSIONS

A dosing regimen should be based on body weight and the application of CRRT. A two-sample strategy for therapeutic drug monitoring could facilitate individualized treatment with polymyxin B in critically ill patients.

Voriconazole pharmacokinetics in a critically ill patient during extracorporeal membrane oxygenation

The pharmacokinetics (PK) of several drugs including antimicrobials might be highly altered during extracorporeal membrane oxygenation (ECMO) therapy. We present the change of voriconazole (VRC) PK during ECMO in a critically ill patient who received intravenous VRC at a maintenance dose of 200 mg every 12 h for empirical antifungal therapy. Two PK profiles were drawn before and after the initiation of ECMO therapy. Though the trough levels (both C₀ and C₁₂) with ECMO were slightly lower than that without ECMO (12.58 and 12.84 vs. 14.02 μg/mL), the peak levels and the area under the concentration-time curve from 0 h to 6 h (AUC_0-6) were comparable (16.36 vs. 16.06 μg/mL and 90.78 vs. 91.45 μg·h/mL, respectively), indicating that VRC plasma exposure during ECMO therapy did not greatly decrease in our patient. The circuit factors including the type of membrane should be taken into account to further identify the effects of ECMO on the PK of VRC.

[Association between dietary vitamin A intake and gestational diabetes mellitus in the first trimester]

Objective: To investigate the relationship between dietary vitamin A intake and its sources in the first trimester and gestational diabetes mellitus (GDM). Methods: A prospective study was conducted to select women at 6-14 weeks of gestation in an obstetric clinic of a maternal and child health care medical institution in Chengdu in 2017. The types and quantities of food during the first trimester were collected by 3-day 24-hour dietary recalls. Dietary vitamin A intake was calculated based on the Chinese Food Composition Table (2018), and it was divided into animal and plant vitamin A intakes according to its food sources. An oral glucose tolerance test was performed at 24-28 weeks of gestation to diagnose GDM according to the Chinese guidelines for diagnosis and treatment of gestational diabetes mellitus (2014). According to the estimated average requirement (EAR) and recommended nutrient intake (RNI), dietary vitamin A intake was divided into low-level group (<EAR), medium-level group (EAR-RNI) and high-level group (>RNI). Animal and plant vitamin A intakes were divided into four groups (Q1-Q4) according to the quartile method, respectively. The association between dietary vitamin A intake, its different sources of vitamin A intake and GDM in the first trimester was analyzed by log-binomial regression models. Results: A total of 1 298 valid samples were finally included. The average dietary vitamin A intake, animal and plant vitamin A intakes in the first trimester were 341.1 (227.8-501.0) μgRAE/d, 139.3 (69.6-195.3) μgRAE/d and 184.2 (99.4-301.1) μgRAE/d, respectively. After adjusting for confounding factors, log-binomial regression analysis showed that the risk of GDM in high-level group of dietary vitamin A intake was lower than that in low-level group [RR (95%CI):0.53 (0.36-0.80)]. Pregnant women in the highest quartile of animal vitamin A intake had a lower risk of GDM than those in the lowest quartile [RR (95%CI):0.66 (0.47-0.95)]. No relationship between plant vitamin A intake and GDM was found. Conclusion: Dietary vitamin A intake in the first trimester is associated with the occurrence of GDM, and higher intake than RNI may reduce the risk of GDM. Higher vitamin A intake from animal-derived food is associated with decreased risk of GDM.

Population pharmacokinetic model-guided optimization of intravenous voriconazole dosing regimens in critically ill patients with liver dysfunction

STUDY OBJECTIVES

This study aimed to establish a population pharmacokinetic (PPK) model of intravenous voriconazole (VRC) in critically ill patients with liver dysfunction and to explore the optimal dosing strategies in specific clinical scenarios for invasive fungal infections (IFIs) caused by common Aspergillus and Candida species.

DESIGN

Prospective pharmacokinetics study.

SETTING

The intensive care unit in a tertiary-care medical center.

PATIENTS

A total of 297 plasma VRC concentrations from 26 critically ill patients with liver dysfunction were included in the PPK analysis.

METHODS

Model-based simulations with therapeutic range of 2-6 mg/L as the plasma trough concentration (C_min ) target and the free area under the concentration-time curve from 0 to 24 h (ƒAUC₂₄ ) divided by the minimum inhibitory concentration (MIC) (ie, ƒAUC₂₄ /MIC) ≥25 as the effective target were performed to optimize VRC dosing regimens for Child-Pugh class A and B (CP-A/B) and Child-Pugh class C (CP-C) patients.

RESULTS

A two-compartment model with first-order elimination adequately described the data. Significant covariates in the final model were body weight on both central and peripheral distribution volume and Child-Pugh class on clearance. Intravenous VRC loading dose of 5 mg/kg every 12 h (q12h) for the first day was adequate for CP-A/B and CP-C patients to attain the C_min target at 24 h. The maintenance dose regimens of 100 mg q12h or 200 mg q24h for CP-A/B patients and 50 mg q12h or 100 mg q24h for CP-C patients could obtain the probability of effective target attainment of >90% at an MIC ≤0.5 mg/L and achieve the cumulative fraction of response of >90% against C. albicans, C. parapsilosis, C. glabrata, C. krusei, A. fumigatus, and A. flavus. Additionally, the daily VRC doses could be increased by 50 mg for CP-A/B and CP-C patients at an MIC of 1 mg/L, with plasma C_min monitored closely to avoid serious adverse events. It is recommended that an appropriate alternative antifungal agent or a combination therapy could be adopted when an MIC ≥2 mg/L is reported, or when the infection is caused by C. tropicalis but the MIC value is not available.

CONCLUSIONS

For critically ill patients with liver dysfunction, the loading dose of intravenous VRC should be reduced to 5 mg/kg q12h. Additionally, based on the types of fungal pathogens and their susceptibility to VRC, the adjusted maintenance dose regimens with lower doses or longer dosing intervals should be considered for CP-A/B and CP-C patients.

Clinical Impacts and Outcomes With Possible Donor-Derived Infection in Infected Donor Liver Transplantation: A Single-Center Retrospective Study in China

BACKGROUND

Information on possible donor-derived transmission events in China is limited. We evaluated the impacts of liver transplantation from infected deceased-donors, analyzed possible donor-derived bacterial or fungal infection events in recipients, and evaluated the etiologic agents' characteristics and cases outcomes.

METHODS

A single-center observational study was performed from January 2015 to March 2017 to retrospectively collect data from deceased-donors diagnosed with infection. Clinical data were recorded for each culture-positive donor and the matched liver recipient. The microorganisms were isolated and identified, and antibiotic sensitivity testing was performed. The pathogens distribution and incidence of possible donor-derived infection (P-DDI) events were analyzed and evaluated.

RESULTS

Information from 211 donors was collected. Of these, 82 donors were infected and classified as the donation after brain death category. Overall, 149 and 138 pathogens were isolated from 82 infected donors and 82 matched liver recipients, respectively. Gram-positive bacteria, Gram-negative bacteria, and fungi accounted for 42.3% (63 of 149), 46.3% (69 of 149), and 11.4% (17 of 149) of pathogens in infected donors. The incidence of multidrug-resistant bacteria was high and Acinetobacter baumannii was the most concerning species. Infections occurred within the first 2 weeks after liver transplantation with an organ from an infected donor. Compared with the noninfection recipient group, the infection recipient group experienced a longer mechanical ventilation time (P = .004) and intensive care unit stay (P = .003), a higher incidence of renal dysfunction (P = .026) and renal replacement therapy (P = .001), and higher hospital mortality (P = .015). Possible donor-derived infection was observed in 14.6% of cases. Recipients with acute-on-chronic liver failure were more prone to have P-DDI than recipients with other diseases (P = .007; odds ratio = 0.114; 95% confidence interval, .025-.529).

CONCLUSIONS

When a liver recipient receives a graft from an infected deceased-donor, the postoperative incidence of infection is high and the infection interval is short. In addition, when a possible donor-derived, drug-resistant bacterial infection occurs, recipients may have serious complications and poor outcomes.

[Association between dietary glycemic load during first trimester and the risk of gestational diabetes mellitus: a prospective study]

Objective: To explore the effects of dietary glycemic load (GL) during first trimester on the risk of gestational diabetes mellitus (GDM). Methods: A prospective study was conducted among healthy women with singleton pregnancy at 8-14 weeks of gestation in a maternity out-patient clinic of maternal-and-child health care institution in Chengdu, Sichuan province. Information on dietary intake during the first trimester was collected through a 3-day 24-hour dietary recall. Glycemic index (GI) values were obtained from China Food Composition Tables (Standard Edition) and International Tables of Glycemic Index and Glycemic Load Values (2008). Dietary GL and GLs of staple foods were calculated based on GI values and the amount of carbohydrate consumed per day. Diagnostic criteria of GDM was followed the Guidelines for Diagnosis and Treatment of Pregnancy Diabetes in China (2014), and used on participants who underwent an oral glucose tolerant test during 24-28 weeks of gestation. Log-binomial regression models were used to explore the associations between both quartiles of dietary GL, GLs of staple foods and the risks of GDM,respectively. Results: The medians of dietary GL and GL of staple foods were 145.70 (113.23-180.85) and 121.05 (89.08-155.70), respectively. The median GL of both rice and tubers were 73.14 (43.89-107.50) and 3.43 (0.00-9.84), respectively. After adjusting for the age at pregnancy, pre-pregnancy body mass index and other confounding factors, results of log-binomial regressions analysis showed that when compared with the lowest quartile of dietary GL group, the third and highest quartiles of dietary GL groups increased the risk of GDM (RR=1.47, 95%CI: 1.20-1.80; RR=1.31, 95%CI: 1.04-1.64), respectively. Compared with the lowest quartile of GL of staple foods, the third and highest quartiles of GL of staple foods groups also increased the risk of GDM (RR=1.28, 95%CI: 1.04-1.58; RR=1.27, 95%CI: 1.02-1.60), respectively. The third and highest quartiles of GL of rice groups increased the risk of GDM (RR=1.30, 95%CI: 1.06-1.59; RR=1.28, 95%CI: 1.03-1.59), respectively, than the lowest quartile of GL of rice group. When compared with the lowest quartile of GL of tubers group, the highest quartile of GL of tubers group increased the risk of GDM (RR=1.30, 95%CI: 1.09-1.54). However, we did not notice the effects of wheat GL and coarse grain GL on the risk of GDM. Conclusions: A positive association was found between dietary glycemic load and the risk of GDM. Higher dietary glycemic load, especially in rice and tubers during first trimester, seemed to have increased the risk of GDM.

Pharmacokinetics of intravenous voriconazole in patients with liver dysfunction: A prospective study in the intensive care unit

OBJECTIVES

To characterize the pharmacokinetics (PK) of intravenous voriconazole (VRC) in critically ill patients with liver dysfunction.

METHODS

Patients with liver dysfunction in the intensive care unit (ICU) were included prospectively. The Child-Pugh score was used to categorize the degree of liver dysfunction. The initial intravenous VRC dosing regimen comprised a loading dose of 300 mg every 12 h for the first 24 h, followed by 200 mg every 12 h. The first PK curves (PK curve 1) were drawn within one dosing interval of the first dose for 17 patients; the second PK curves (PK curve 2) were drawn within one dosing interval after a minimum of seven doses for 12 patients. PK parameters were estimated by non-compartmental analysis.

RESULTS

There were good correlations between the area under the curve (AUC_0-12) of PK curve 2 and the corresponding trough concentration (C₀) and peak concentration (C_max) (r² = 0.951 and 0.963, respectively; both p < 0.001). The median half-life (t_1/2) and clearance (CL) of patients in Child-Pugh class A (n = 3), B (n = 5), and C (n = 4) of PK curve 2 were 24.4 h and 3.31 l/h, 29.1 h and 2.54 l/h, and 60.7 h and 2.04 l/h, respectively. In the different Child-Pugh classes, the CL (median) of PK curve 2 were all lower than those of PK curve 1. The apparent steady-state volume of distribution (V_ss) of PK curve 1 was positively correlated with actual body weight (r² = 0.450, p = 0.004). The median first C₀ of 17 patients determined on day 5 was 5.27 (2.61) μg/ml, and 29.4% of C₀ exceeded the upper limit of the therapeutic window (2-6 μg/ml).

CONCLUSIONS

The CL of VRC decreased with increasing severity of liver dysfunction according to the Child-Pugh classification, along with an increased t_1/2, which resulted in high plasma exposure of VRC. Adjusted dosing regimens of intravenous VRC should be established based on Child-Pugh classes for these ICU patients, and plasma concentrations should be monitored closely to avoid serious adverse events.

Dynamics of methanogenesis, ruminal fermentation, and alfalfa degradation during adaptation to monensin supplementation in goats

This study aimed to examine the temporal (hourly within a day and daily over the long term) effects of monensin on CH₄ emissions, ruminal fermentation, and in situ alfalfa degradation in dairy goats during dietary monensin supplementation by controlling the confounding effects of feed intake and ambient temperature. Six ruminally cannulated dairy goats were used, and they were housed in environmental chambers and fed a restricted amount of ration throughout the experiment. The experiment included a baseline period of 20 d followed by a treatment period of 55 d with 32 mg of monensin/d. During the whole experiment, CH₄ production was measured every 5 d, whereas fermentation characteristics and in situ alfalfa degradation were analyzed every 10 d. The CH₄-depressing effect of monensin was time dependent on the duration of treatment, highly effective at d 5 but thereafter decreased gradually until d 55 even though CH₄-suppressing effect still remained significant. The decreasing effects of monensin on ruminal acetate proportion and acetate to propionate ratio also faded over days of treatment, and the acetate proportion returned up to the pre-supplementation level on d 50. Monensin supplementation elevated ruminal propionate proportion and decreased the effective ruminal degradability of alfalfa NDF, but both measurements tended to recover over time. The postprandial increase rate of hourly CH₄ emissions was reduced, whereas that of propionate proportion was enhanced by monensin supplementation. However, the postprandial responses to monensin in CH₄ emission rates, ruminal VFA profiles, and in situ degradation kinetics declined with both hours after feeding and days of treatment. Our results suggest that the CH₄-suppressing effect of monensin supplementation in goats was attributed to reductions in both ruminal feed degradation and acetate to propionate ratio, but those reductions faded with time, hours after feeding, and days of treatment.

Pseudogene integrator complex subunit 6 pseudogene 1 (INTS6P1) as a novel plasma-based biomarker for hepatocellular carcinoma screening

In this study, we aimed to determine whether the pseudogene integrator complex subunit 6 pseudogene 1 (INTS6P1) in plasma could be used as a novel approach to screen for and detect hepatocellular carcinoma (HCC). We explored the clinical role of INTS6P1: First, the expression level of INTS6P1 was measured in a cohort of 33 HCC tissue samples and adjacent normal liver tissue, next, the INTS6P1 expression was detected in the culture medium and tumor cells in a cellular experiment, and last, the diagnostic performance of INTS6P1 was examined in an independent cohort of 100 people. The expression level of INTS6P1 was remarkably downregulated in the HCC tissues compared with that in the normal liver tissues (p = 0.0066). In plasma, the INTS6P1 levels were significantly decreased in HCC patients compared with non-HCC patients (p < 0.01). Additionally, we inferred that INTS6P1 might be a prospective biomarker for screening HCC patients in which the serum-AFP levels were lower than 20 ng/ml by the area under the curve-receiver operating characteristic (AUC-ROC) analysis (p < 0.05). Pseudogene INTS6P1 could be used as a novel HCC plasma-based biomarker and might improve the accuracy of HCC screening.

Pathological characteristics of liver allografts from donation after brain death followed by cardiac death in pigs

Donation after brain death followed by circulatory death (DBCD) is a unique practice in China. The aim of this study was to define the pathologic characteristics of DBCD liver allografts in a porcine model. Fifteen male pigs (25-30 kg) were allocated randomly into donation after brain death (DBD), donation after circulatory death (DCD) and DBCD groups. Brain death was induced by augmenting intracranial pressure. Circulatory death was induced by withdrawal of life support in DBCD group and by venous injection of 40 mL 10% potassium chloride in DCD group. The donor livers were perfused in situ and kept in cold storage for 4 h. Liver tissue and common bile duct samples were collected for hematoxylin and eosin staining, TUNEL testing and electron microscopic examination. Spot necrosis was found in hepatic parenchyma of DBD and DBCD groups, while a large area of necrosis was shown in DCD group. The apoptosis rate of hepatocytes in DBD [(0.56±0.30)%] and DBCD [(0.50 ± 0.11)%] groups was much lower than that in DCD group [(3.78±0.33)%] (P<0.05). And there was no significant difference between DBD group and DBCD group (P>0.05)). The structures of bile duct were intact in both DBD and DBCD groups, while the biliary epithelium was totally damaged in DCD group. Under electron microscope, the DBD hepatocytes were characterized by intact cell membrane, well-organized endoplasmic reticulum, mild mitochondria edema and abundant glycogens. Broken cell membrane, mild inflammatory cell infiltration and sinusoidal epithelium edema, as well as reduced glycogen volume, were found in the DBCD hepatocytes. The DCD hepatocytes had more profound cell organelle injury and much less glycogen storage. In conclusion, the preservation injury of DBCD liver allografts is much less severe than that of un-controlled DCD, but more severe than that of DBD liver allografts under electron microscope, which might reflect post-transplant liver function to some extent.

Dietary supplementation with Lactobacillus fermentum I5007 improves the anti-oxidative activity of weanling piglets challenged with diquat

AIMS

To determine the effects of Lactobacillus fermentum I5007 on the redox state of piglets oxidatively stressed with diquat.

METHODS AND RESULTS

Twenty-four, 28-day-old barrows were used in a 2 × 2 factorial design experiment with the main effects being Lact. fermentum supplementation and diquat challenge. Half of the pigs (n = 12) were orally administered with 20 ml of a solution containing 10(8 ) CFU ml(-1) of Lact. fermentum each morning of the 21-day trial, while the remainder received saline. On day 8, these two groups were further subdivided so that half of the pigs in each group (n = 6) were intraperitoneally injected with 10 mg kg(-1) BW diquat, while the remainder received saline. The diquat-injected pigs had significantly poorer performance and increased levels of plasma cortisol, adrenaline, carbonyl and malondialdehyde. Lactobacillus fermentum supplementation significantly increased superoxide dismutase and glutathione and increased the ability to inhibit superoxide anion production in liver and muscle.

CONCLUSIONS

Lactobacillus fermentum improved the anti-oxidative defence system and alleviated damage caused by diquat.

SIGNIFICANCE AND IMPACT OF THE STUDY

Lactobacillus fermentum has the potential to alleviate oxidative stress and improve weaning pig performance.

Prognostic factors for late mortality after liver transplantation for benign end-stage liver disease

BACKGROUND

There are increasing numbers of patients who survive more than one year after liver transplantation. Many studies have focused on the early mortality of these patients. However, the factors affecting long-term survival are not fully understood. This study aims to evaluate prognostic factors predicting long-term survival and to explore measures for improving the survival outcomes of patients who underwent liver transplantation for benign end-stage liver diseases.

METHODS

The causes of late death after liver transplantation and potential prognostic factors were retrospectively analyzed for 221 consecutive patients who underwent liver transplantation from October 2003 to June 2008. Twenty-seven variables were assessed using the Kaplan-Meier method, and those variables found to be univariately significant at P < 0.10 were entered into a backward step-down Cox proportional hazard regression analysis to identify the independent prognostic factors influencing the recipients' long-term survival.

RESULTS

Twenty-eight recipients died one year after liver transplantation. The major causes of late mortality were infectious complications, biliary complications, and Hepatitis B virus recurrence/reinfection. After Cox analysis, the five remaining co-variables were: age, ABO blood group, cold ischemia time, post-infection region, and biliary complications.

CONCLUSIONS

The major causes of late mortality were infection, biliary complications and Hepatitis B virus recurrence/reinfection. Five variables (Age, ABO blood group, cold ischemia time, infection, and biliary complications) had significant impacts on patient survival.

Three-dimensional structure of the hepatitis B core antigen particle truncated at residue 154

The three-dimensional structure of recombinant hepatitis B core antigen (HBcAg) particles truncated at residue 154 (HBcAg-154) was determined to 7.8 Å resolution by cryo-electron microscopy (cryoEM) and computer reconstruction. The capsid of HBcAg-154 is mainly constituted by α-helical folds, highly similar to that of HBcAg-149. The C-terminal region between residues 155 and 183 of the core protein is more crucial to the encapsidation of RNA, and the short C-terminal tail of HBcAg-154 results in a nearly empty capsid.

[Risk factors predicting late mortality after liver transplantation for benign end-stage liver disease]

OBJECTIVES

To find out the risk factors predicting long-term survival, and to explore the measures for further improving the survival outcome of whom underwent liver transplantation (LT) for benign end-stage liver disease.

METHODS

The common causes of late death after LT and risk factors were retrospectively analyzed in 221 consecutive patients, who underwent LT from October 2003 to June 2007 and survived more than one year. Twenty-six potential risk factors were assessed by the Kaplan-Meier method, and those variables found to be univariately significant at P < 0.10 were entered into a backward step down Cox proportional hazard regression analysis to screen the independent risk factors influencing the recipient's long-term survival.

RESULTS

There were 28 recipients died one year later after LT during the follow-up period. The major causes of late mortality were related to infectious complications 5.0% (11/221), biliary complications 3.6% (8/221) and HBV recurrence/reinfection 1.4% (3/221). After Cox proportional hazard regression analysis, 5 covariables finally retained in the formula were: age (RR = 2.325, P = 0.009), ABO blood group (RR = 2.206, P = 0.015), cold ischemia time (RR = 3.001, P = 0.000), post-infection region (RR = 1.665, P = 0.007) and biliary complications (RR = 2.655, P = 0.004).

CONCLUSION

Age (≥ 60 years), ABO blood group (incompatible), cold ischemia time (> 12 h), infectious complications (lung infection) and biliary complications (diffuse biliary stricture) significantly impact patient's survival time.

Contrast-enhanced ultrasound for the evaluation of hepatic artery stenosis after liver transplantation: potential role in changing the clinical algorithm

Hepatic artery stenosis (HAS) is a common complication in liver transplant patients. Conventional angiography remains the gold standard for diagnosis. Recently, contrast-enhanced ultrasound (CEUS) has begun providing real-time angiographic-like images of vessels and allowing the accurate diagnosis of arterial diseases such as hepatic artery thrombosis. The purpose of this study was to evaluate the efficacy of CEUS in depicting HAS after liver transplantation. Forty-seven liver transplant recipients underwent CEUS examinations with the intravenous injection of microbubble contrast agents. The reference standard was conventional angiography for 15 patients and computed tomographic angiography for 32 patients. The presence, degree, location, and type of HAS were evaluated. For the detection of HAS by CEUS, the following was found: an accuracy of 91.5% (43/47), a sensitivity of 92.3% (36/39), a specificity of 87.5% (7/8), a positive predictive value of 97.3% (36/37), and a negative predictive value of 70% (7/10). CEUS corrected false-positive findings on color Doppler ultrasound in 7 of 47 cases (14.9%). The accuracy of CEUS in identifying the location and type of HAS was 92.3% (36/39) and 84.6% (33/39), respectively. CEUS is a useful noninvasive technique for the detection of HAS in liver transplant patients because it provides comprehensive information, including the presence, location, degree, and type. A positive CEUS finding suggests angiography as the next step rather than a computed tomography scan and may thereby alter the clinical imaging algorithm.

[Effect of artificial liver support system on the survival rate of high risk patients after liver transplantation]

OBJECTIVE

To observe the effect of artificial liver support system (ALSS) after liver transplantation on the survival rate of severe hepatitis patients.

METHODS

Patients with severe hepatitis with model for end stage liver disease (MELD) score above 35 were divided into two groups according to whether pre-transplantation ALSS was instituted (n=23) or not (n=41). Evaluation was performed on the day when the patient entered into the waiting list and 1 day pre-transplantation. Survival rates and survival curves were estimated with Kaplan-Meier method. Log-Rank test for trends was used when comparing curves.

RESULTS

There was no significant difference between two groups when comparing the parameters including prothrombin time, fibrinogen, total bilirubin, blood ammonia, creatinine, MELD score on the day of entering into the waiting list (all P>0.05). After the therapy of ALSS, the parameters of ALSS group were significantly improved comparing to those of the control group (all P<0.01). MELD score of ALSS group on the day pre-transplant was decreased significantly comparing to that on the day entering into the waiting list (37.6+/-2.0 vs. 41.4+/-2.2, P<0.01), with the difference in MELD score (DeltaMELD) of -3.8. MELD score of control group on the day entering into the waiting list and 1 day pre-transplant was 40.6+/-1.7 and 41.0+/-1.6 respectively, with DeltaMELD of +0.4 ( P>0.05). The blood loss and operation time in ALSS group was significantly less than the control group [(4 070.0+/-688.1) ml vs. (4 905.9+/-1 142.1) ml, (9.4+/-1.1) hours vs. (10.5+/-1.0) hours, P<0.05 and P<0.01). Thirty days and 1 year survival rate of ALSS group was 91% and 82%, and that of control group was 76% and 59% respectively (P=0.044).

CONCLUSION

ALSS can improve the survival rate of patients with severe hepatitis undergoing liver transplantation through ameliorating physiological status, lessening blood loss during operation and operation time.

[Significance of lipopolysaccharides, toll-like receptor and inducible nitric oxide synthase in hepatopulmonary syndrome]

OBJECTIVE

To investigate the role of lipopolysaccharides (LPS), toll-like receptor 2 (TLR2) and inducible nitric oxide synthase (iNOS) in the development of hepatopulmonary syndrome (HPS).

METHODS

Seventy-one patients were divided into 3 groups: end-stage liver disease with HPS (HPS group, n = 31), end-stage liver disease without HPS (non-HPS group, n = 30) and healthy volunteers (n = 10). Blood was collected at pre-OLT and Days 3, 7, 14, 21 and 28 post-OLT to detect the plasma LPS level, TLR2mRNA and iNOSmRNA in peripheral blood monocytes.

RESULTS

The LPS, TLR2mRNA and iNOSmRNA at pre-OLT in HPS group were 4.31 +/- 3.267 ng/L, 336,594.10 +/- 366,901.14 and 63,982.24 +/- 74,127.47 copies/microg RNA respectively; 1.62 +/- 1.34 ng/L, 336,321.53 +/- 222,317.17 and 44,169.9 +/- 24,993.00 copies/microg RNA respectively in non-HPS group and 0.94 +/- .69 ng/L, 10,338.28 +/- 3,814.64 and 19,168.49 +/- 2,417.35 copies/microg RNA in normal control group. LPS, TLR2mRNA and iNOSmRNA at pre-OLT in HPS group were higher than those in non-HPS group without significance (P > 0.05), but significantly higher than those in control group (P < 0.05). The TLR2mRNA decreased in all end-stage liver disease patients at post-OLT with the improvement of liver function and oxygenation.

CONCLUSION

The dysfunction of intestinal barrier and intestinal endotoxemia may be the important mechanisms of HPS through the elevation of LPS level and the expressions of TLR2mRNA and iNOSmRNA.

[Immunization with dendritic cells infected with mTERT adenovirus vector effectively elicits immunity against mouse H22 hepatoma in vivo]

OBJECTIVE

To investigate the effects of dendritic cells (DCs) infected with adenovirus vector encoding mTERT on induction of mTERT antigen specific immunity against H22 hepatoma in vivo.

METHODS

Forty Bal B/c mice were subcutaneously immunized with Ad-mTERT infected DC. Cytotoxicity of mTERT specific CTL was determined by 51Cr release assay. IL-2 and IFN-gamma were tested by ELISA. IFN-gamma ELISPOT assays were performed for measuring antigen specific IFN-gamma production by T cells. Tumor size and survival of the immunized mice were recorded and evaluated whether preexisting hepatoma metastases could be supressed after immunization with mTERT-expressing DCs.

RESULTS

The lytic activity of CTL, IL-2 (871.25 pg/ml), IFN-gamma (169.15 ng/ml) and IFN-gamma secreting cells (378/10(6) spleen cells) elicited by the Ad-mTERT infected DCs were much stronger and higher than that by Ad-GFP group (131.6 pg/ml, 15.4 ng/ml, 36/10(6) spleen cells, P<0.05), DC group (71.3 pg/ml, 10.5 ng/ml, 21/10(6) spleen cells, P<0.05), PBS group (65.8 pg/ml, 7.4 ng/ml, 18/10(6) spleen cells, P<0.05). In prophylaxis and treatment experiment the Ad-mTERT/DCs immunized mice lived significantly longer than other groups, demonstrating that primary DCs were genetically modified to express the mTERT antigen and could suppress the tumor growth.

CONCLUSION

Adenovirus vector mediated mTERT infected DCs can effectively induce mTERT antigen specific antitumor activity, and can induce protective and therapeutic antitumor immunity.

Acute leukemia, a rare but fatal complication after liver transplantation

Little information is available about the risk factors and means to improve the survival rate of acute leukemia in a rare but often fatal complication after liver transplantation (LT). We report the development of AML-M2 in one of the 764 patients who underwent liver transplantation at our center, and review the literature on similar cases. The patient, a 42-year-old man who developed acute leukemia 38 months after liver transplantation, was successfully treated with chemotherapy and has subsequently been in remission. With appropriate adjustment of immunosuppressive agents, he was able to safely benefit from chemotherapy. Only 16 patients with acute leukemia after liver transplantation have been reported, and the mortality rate is extraordinarily high (52.94%, 9/17). More cases of acute leukemia will emerge as the rate of survival after liver transplantation increases. The patient's chromosomal mutation profile, the choice of immunosuppressive agent, and infection by hepatitis virus may be the risk factors for the development of acute leukemia after LT. Our experience suggests that clinicians should adjust the immunosuppressive agents according to the immunosuppressive state of the patient and explore the option of reducing or stopping the medication as long as liver function remains stable. These measures could help reduce the high mortality rate among these patients.

[Long-term survival after liver transplantation for benign end-stage liver disease in adults]

OBJECTIVE

To evaluate the long-term survival rates of the adults with benign end-stage liver disease (BELD) after liver transplantation (LT) and the causes of death.

METHODS

The common causes of late death (after more than 1 year) after LT were retrospectively analyzed in 203 consecutive patients with BELD who underwent LT from Oct. 2003 to May.2006.

RESULTS

The 1, 2 and 3-year survival rates were 88.7%, 85.5%, and 81.2% respectively. The 2-year and 3-year survival rates of the patients with HBV-related liver disease were 88.4% and 84.5% respectively, not significantly different from those of patients with non-HBV-related liver disease (75.6% and 64.0% respectively, P = 0.144). 165 recipients survived for more than 1 year and 21 recipients died during the period between 12 and 48 months after LT with a mean of (22.7 +/- 6.6) months. The common causes of late death included related to infectious complications (4.8%, 8/165), biliary tract complications (3.6%, 6/165), HBV re-infection (1.8%, 3/165), chronic rejection (1.2%, 2/165), renal functional lesion (0.6%, 1/165), and hepatic arterial complication (0.6%1/165).

CONCLUSION

Satisfactory long-term survival can be achieved in most adult recipients with BELD after LT and the major causes that influence the long-term survival are infectious complications, biliary tract complications, and HBV re-infection. Prevention of these complications, rational use of immunosuppressant, and regular follow-up are essential to improve long-term survival.

[Application of somatostatin combined with oral vancomycin in the treatment of intestinal obstruction after liver transplantation]

OBJECTIVE

To investigate the effect of somatostatin combined with oral vancomycin in the treatment of intestinal obstruction after liver transplantation.

METHODS

Fifty-eight cases of intestinal obstruction after liver transplantation from Jan. 2005 to Dec. 2006 were divided into two groups: Group A (from Jan. 2005 to Dec. 2005) received traditional treatment, including fasting,gastrointestinal decompression, maintaining electrolyte and acid-base balance, enteral and parenteral nutrition support and antibiotics; Group B (from Jan. 2006 to Dec. 2006) received somatostatin combined oral vancomycin in addition to the above mentioned traditional treatment.

RESULTS

Fifty-eight cases out of 441 patients (13%) suffered from intestinal obstruction after liver transplantation. Group B had a better outcome as compared with Group A, including a quick recovery of flatus and stool, [(7.1+/-2.0) d and (8.4+/-2.4) d vs (9.1+/-3.0) d and (10.8+/-3.4) d] (P<0.05), less amount of gastric drainage [(298+/-58) ml/d vs (485+/-106) ml/d](P<0.05). The rate of intestinal flora imbalance in Group B was 55%, which was significantly less than the 77% in Group A(P<0.05).

CONCLUSION

The application of somatostatin combined with oral vancomycin can improve the symptoms of intestinal obstruction after liver transplantation and decrease the rate of intestinal flora imbalance.

[Effects of gene transfer CTLA4-Ig and anti-CD154 monoclonal antibody on the rejection of rat islet xenografts]

OBJECTIVE

To study the effects of gene transfer cytotoxic T lymphocyte associated antigen 4 immunoglobulin (CTLA4-Ig) and anti-cluster of differentiation 154 (CD154) mAb on the rejection of rat islet xenografts.

METHODS

Human islets were infected with the recombinant adenoviruses containing CTLA4-Ig gene. Transduced islets were transplanted under the left kidney capsule of diabetic rats. And then the animal model were treated with anti-CD154 monoclonal antibody. The changes of blood sugar were measured and the survival rates of grafts and transplantation rats were observed after transplantation. The morphological changes of grafts were observed. Expression of CTLA4-Ig and insulin were detected by immunohistochemical staining and cytokines were quantified by ELISA.

RESULTS

(1) The blood glucose of transplantation rats decreased to normal level on 2nd day post-transplantation. The average level blood glucose of control group A, anti-CD154mAb treatment group B, transfected group C and associated treatment group D increased on day 8, 18, 25, 36, post-transplantation respectively. (2) The grafts of group A, B, C and D survived for (10.0 +/- 2.1) d, (22.0 +/- 8.2) d, (28.0 +/- 6.5) d and (37.0 +/- 9.3) d respectively. The survival of grafts in group D was significant longer than that in group A, B and C, respectively; The survival of group B and C were significantly prolonged compared with group A and the survival of group B was significantly different with group C (P < 0.05). The survival of transplantation rats were (21.0 +/- 5.7) d, (35.0 +/- 6.5) d, (48.0 +/- 8.5) d and (65.0 +/- 12.5) d in group A, B, C and D, respectively. The survival of transplantation rats compared each other among four groups were same as the survival of grafts (P < 0.05). (3) In control animals (group A), serum IL-2 and TNF-alpha concentration were elevated to a high level within seven days post-transplantation and significantly increased compared with that before transplantation (P < 0.01). (4) Hematoxylin-eosin staining of grafts showed a lot of islets under the kidney capsule of transplantation rats, no inflammatory cell infiltrate and immunohistochemical staining of grafts demonstrated expression of insulin protein at islets in group B, C and D. These grafts positively stained for CTLA4-Ig in group C and D.

CONCLUSIONS

Gene transfer CTLA4-Ig and anti-CD154mAb treatment can inhibit the rejection of rat islet xenografts and treatment Ad-CTLA4-Ig and anti-CD154 mAb could induce immune tolerance of islet xenografts.

[Anatomical variation of the donor hepatic arteries: analysis of 843 cases]

OBJECTIVE

To investigate the anatomical variations of donor hepatic artery and explore the measures that can be taken to avoid accidental hepatic artery injury during graft procurement and reconstruction.

METHODS

The data of totally 843 consecutive patients undergoing orthotopic liver transplantation (OLT) during the period from April 2001 to July 2006 was reviewed in relation to anatomical variation of the donor hepatic arteries. The variations of the hepatic artery, the relationship between the anomalous hepatic artery and accidental injury of the hepatic artery were analyzed.

RESULTS

In the 843 cases of OLT, the total anatomical variation rate of the donor hepatic arteries was 20.4% (172/843). The common variations included replaced or accessory right hepatic arteries originated from superior mesenteric artery (6.67%, 57/843), replaced or accessory left hepatic arteries originated from the left gastric artery (6.41%, 54/843) or from the celiac trunk and gastro-duodenal artery (1.66%, 14/843), replaced or accessory right hepatic arteries originated from the celiac trunk, common hepatic artery and gastro-duodenal artery (1.54%,13/843), replaced or accessory right hepatic arteries and left hepatic arteries coexistence (0.83%, 7/843), variation of the common hepatic artery from the superior mesenteric artery (1.54%, 13/843) or from the abdominal aorta (0.95%, 8/843).

CONCLUSION

During graft procurement and reconstruction, accidental injury of the hepatic artery is more likely in the presence of hepatic arterial variation, which can be a common clinical entity. Acquaintance with hepatic arterial variation and maintenance of the integrity of the superior mesenteric artery and celiac trunk are key to reducing potential hepatic artery injuries.

Alleviation of ischemia-reperfusion injury in rat liver transplantation by induction of small interference RNA targeting Fas

BACKGROUND

Cellular apoptosis plays an important role in ischemia-reperfusion (I/R) injury during organ transplantation. Synthetic small interference RNA (siRNA) targeting apoptotic receptor Fas has proven effective to protect mice against hepatitis and renal I/R injury. The objective of this study is to investigate the silencing impact of Fas siRNA to alleviate I/R injury in rat liver transplantation.

MATERIALS AND METHODS

Rat hepatocytes (BRL cells) were transfected with three pairs of synthesized Fas siRNA; cells untreated and treated with GFP siRNA were taken as blank and siRNA control. The most effective Fas siRNA was chosen for in vivo experiments. Syngeneic orthotopic liver transplantation was performed in Fas siRNA group, siRNA control group, and blank control group of Sprague-Dawley rats. There were 25 pairs of rats in each group. siRNA transfection of donor rats was done with hydrodynamic injection method 48 h before liver procurement. Blood and liver samples were collected for evaluation of serum ALT levels, Fas protein and mRNA expression, and apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining, 1, 3, 6, 12, and 24 h after liver transplantation.

RESULTS

Fas siRNA2, which inhibited Fas gene expression much more than other siRNAs, was chosen for in vivo experiment. The serum ALT levels of Fas siRNA group were much less than those of blank and siRNA control groups 1, 3, 6, 12, and 24 h after blood reperfusion, indicating diminishing ischemia-reperfusion injury. Donor livers in Fas siRNA group had substantially less cell apoptosis. The expression of Fas mRNA and protein was reduced dramatically in the Fas siRNA group compared with the other two groups.

CONCLUSION

Fas-mediated apoptosis play an important role in I/R injury of rat liver transplantation. Silencing Fas by hydrodynamic injection of siRNA holds therapeutic promise to limit I/R injury.

Rapamycin inhibits cell growth by induction of apoptosis on hepatocellular carcinoma cells in vitro

BACKGROUND

Rapamycin, isolated from Streptomyces hygroscopicus, is recently reported to have immunosuppressant and anti-tumor effects on a large variety of cancers. To date, no detailed data are available about the effects of rapamycin on hepatocellular carcinoma cells.

OBJECTIVE

In this study, the anti-proliferation effects of rapamycin on hepatocellular carcinoma cells BEL-7402 and HepG-2 in vitro were studied.

METHODS

Cell viability was assessed by MTT assay and [3H]-thymidine uptake, cell apoptosis was observed by Hoechst 33258 staining and flow cytometry (FCM). The variation of caspase-3 and apoptotic related genes was assayed by Western blotting, cell mitochondrial membrane potential was also investigated by using standard methods.

RESULTS

Rapamycin could inhibit the growth of hepatocellular carcinoma cells and cause apoptosis significantly; the suppression was both in time- and dose-dependent manner, marked morphological changes of cell apoptosis were observed very clearly by Hoechst 33258 staining. Rapamycin exhibits induction apoptosis by activation of caspase-3 and disruption of the mitochondrial membrane potential on hepatocellular carcinoma cells in vitro. Western blotting analysis demonstrated that anti-apoptotic protein Bcl-2 was down-regulated while pro-apoptotic protein Bcl-xl up-regulated remarkably in a time-dependent manner when apoptosis occurred.

CONCLUSION

Rapamycin has significant anti-proliferation effect by induction of apoptosis via activation of caspase-3 and disruption of mitochondrial membrane potential, as well as by down-regulation of anti-apoptotic protein Bcl-2 and up-regulation of pro-apoptotic protein Bcl-xl on hepatocellular carcinoma cells. The data provide a potential mechanism for rapamycin-induced apoptosis in hepatocellular carcinoma cells, suggesting that rapamycin may serve as both an effective adjunctive reagent for the treatment of residual cancer cells and immunosuppressant after liver transplantation of hepatocellular carcinoma, and that in vivo anti-cancer effects as well as its potential clinical effectiveness need further investigation.

[The role of caspase-3 in rapamycin-induced apoptosis of hepatocellular carcinoma BEL-7402 cells]

BACKGROUND & OBJECTIVE

Rapamycin, isolated from Streptomyces hygroscopicus, is recently reported to have immunosuppressive and antitumor effects on a large variety of cancers. This study was to investigate the role of Caspase-3 in rapamycin-induced apoptosis of hepatocellular carcinoma BEL-7402 cells.

METHODS

BEL-7402 cells were treated with different concentrations (5, 10, 20, 30, 40, 50 nmol/L) of rapamycin. Cell viability was detected by MTT assay; cell apoptosis was observed by flow cytometry (FCM) and Hoechst 33258 staining. The activity of Caspase-3 was determined by Caspase colorimetric assay kit and Western blot.

RESULTS

Rapamycin inhibited the growth of BEL-7402 cells and induced apoptosis significantly in time- and dose-dependent manners. Marked morphologic changes of cell apoptosis, such as chromatin condensation and nuclear fragmentation, were observed clearly at 48 h after exposion to rapamycin; Caspase-3 was activated by the loss of Caspase-3 proenzyme (32-ku) and its 20-ku subunit appeared at 24 h after incubation. Caspase-3 inhibitor z-DEVD-FMK could block the apoptosis induced by rapamycin.

CONCLUSIONS

Rapamycin can inhibit growth and induce apoptosis of BEL-7402 cells. The activation of Caspase-3 may play an important role in cell apoptosis.

[Change of Bcl-2 expression and telomerase during apoptosis induced by oridonin on human hepatocelluar carcinoma cells]

OBJECTIVE

To investigate the change of Bcl-2 expression and telomerase during the apoptosis induced by oridonin on human hepatocelluar carcinoma BEL7402 cells.

METHOD

BEL-7402 cells in culture medium were given 8,16,24,32 micromol x L(-1) different concentrations of oridonin. The cell apoptotic rate was detected by flow cytometry (FCM), morphology of cell apoptosis was observed by Hoechst 3325 staining. Bcl-2 and Bax expressions were detected by Western blotting. Reverse transcriptase polymerase chain reaction (RT-PCR) and PCR enzyme-linked immunosorbent assay (ELISA) were used to detect hTERT mRNA expression and telomerase activity.

RESULT

Oridonin induced BEL-7402 cells apoptosis significantly, and the apoptosis rate was both in time-and dose-dependent manner. Marked morphological changes of cell apoptosis were observed very clearly by Hoechst 33258 staining after the cells exposed to oridonin for 60 hours; Western blotting showed that Bcl-2 expression was down-regulated and Bax expression up-regulated concurrently along with the apoptotic process, and the expression of hTERT mRNA as well as activity of telomerase were decreased concurrently.

CONCLUSION

Oridonin could decrease the expression of hTERT mRNA and telomerase activity as well as down-regulation of Bcl-2 and up-regulation of Bax expression during the apoptosis of BEL-7402 cells.

[The practical value of endoscopic retrograde cholangiography in biliary complications after liver transplantation]

OBJECTIVE

To investigate the practical value of endoscopic retrograde cholangiography (ERC) in biliary complications after liver transplantation.

METHODS

The data of 71 biliary complications after liver transplantation were analyzed retrospectively. All patients were diagnosed and treated by ERC in our center from October 2003 to March 2006. The biliary complications included 52 cases of biliary stricture, 6 biliary leakage and 13 biliary stone.

RESULTS

The diagnostic rate of ERC for biliary stricture, leakage and stone was 98.1% (51/52), 100% (6/6) and 100% (13/13), respectively. The cure rate of interventional therapy through therapeutic ERC for anastomotic, extrahepatic, hilar, intrahepatic and diffuse biliary stricture was 66.7% (4/6), 66.7% (10/15), 0 (0/7), 0 (0/2) and 0 (0/21), respectively. And that for biliary leakage, common bile duct and intrahepatic bile duct stone was 66.7% (4/6), 77.8% (7/9) and 0 (0/4), respectively.

CONCLUSIONS

ERC is effective for diagnosis of biliary complications after liver transplantation. The effect of interventional therapy through ERC varies with the type of biliary complications. Only part of biliary complications (anastomotic stricture, extrahepatic biliary stricture, gently and moderate biliary leakage, common bile duct stone) can be cured by interventional therapy through ERC.

Kinetics of phytohemaglutinin-induced IFN-γ and TNF-α expression in peripheral blood mononuclear cells from patients with chronic hepatitis B after liver transplantation

AIM: To study the association between host immunity and hepatitis B virus (HBV) recurrence after liver transplantation.

METHODS: Peripheral blood mononuclear cells (PBMC) were isolated from 40 patients with hepatitis B and underwent orthotopic liver transplantation (OLT) before and 2, 4, 8 wk after surgery. After being cultured in vitro for 72 h, the levels of INF-γ and TNF-α in culture supernatants were detected with ELISA. At the same time, the quantities of HBV DNA in serum and PBMCs were measured by real time PCR.

RESULTS: The levels of INF-γ and TNF-α in PBMC culture supernatants decreased before and 2, 4 wk after surgery in turns (INF-γ 155.52±72.32 ng/L vs 14.76±9.88 ng/L vs 13.22±10.35 ng/L, F = 6.946, P = 0.027<0.05; TNF-α 80.839±46.75 ng/L vs 18.59±17.29 ng/L vs 9.758±7.96 ng/L, F = 22.61, P = 0.0001<0.05). The levels of INF-γ and TNF-α were higher in groups with phytohemagglutinin (PHA) than in those without PHA before surgery. However, the difference disappeared following OLT. Furthermore, INF-γ and TNF-α could not be detected in most patients at wk 4 and none at wk 8 after OLT. The HBV detection rate and virus load in PBMC before and 2, 4 wk after surgery were fluctuated (HBV detected rate: 51.4%, 13.3%, 50% respectively; HBV DNA: 3.55±0.674 log(10) copies/mL vs 3.00±0.329 log(10) copies/mL vs 4.608±1.344 log(10) copies/mL, F = 7.582, P = 0.002<0.05). HBV DNA in serum was 4.48±1.463 log(10) copies/mL before surgery and <103 copies/mL after OLT except for one with 5.72±106 copies/mL 4 wk after OLT who was diagnosed as HBV recurrence. The levels of INF-γ and TNF-α were lower in patients with a high HBV load than in those with a low HBV load (HBV DNA detected/undetected in PBMCs: IFN-γ 138.08±72.44 ng/L vs 164.24±72.07 ng/L, t = 1.065, P = 0.297>0.05, TNF-α 80.75±47.30 ng/L vs 74.10±49.70 ng/L, t = 0.407, P = 0.686>0.05; HBV DNA positive/negative: IFN-γ 136.77±70.04 ng/L vs 175.27±71.50 ng/L, t = 1.702, P = 0.097>0.05; TNF-α 75.37±43.02 ng/L vs 81.53±52.46 ng/L, t = 0.402, P = 0.690>0.05).

CONCLUSION: The yielding of INF-γ and TNF-α from PBMCs is inhibited significantly by immunosuppressive agents following OLT with HBV load increased, indicating that the impaired immunity of host is associated with HBV recurrence after OLT.

[Clinical study of adjuvant individualized chemotherapy for hepatocellular carcinoma after liver transplantation]

OBJECTIVE

To investigate the effect of adjuvant individualized chemotherapy in prevention of tumor recurrence and improvement of patient survival after liver transplantation for hepatocellular carcinoma (HCC).

METHODS

21 HCC cases received orthotopic liver transplantation and treated with adjuvant individualized chemotherapy based on ATP tumor chemosensitivity assay (ex vivo) between April 2001 and January 2003 were retrospective reviewed, compared with 52 cases received orthotopic liver transplantation only. The cumulative and tumor-free survivals were compared between 2 groups.

RESULTS

The 1, 2 years overall survival rates were 92.31%, 73.85% for the individualized chemotherapy group and 92.06%, 63.93% for the non-chemotherapy group, the difference was not statistically significant. The 6, 12, 18, 24 months tumor-free survival rates were 90.00%, 80.00%, 80.00%, 60.00% and 67.31%, 51.92%, 40.03%, 37.81% respectively, the difference was statistically significant (P <0.05).

CONCLUSIONS

This study suggests that tumor recurrence decreases and tumor-free survival increases by adjuvant individualized chemotherapy after liver transplantation for HCC. The individualized protocol based on ATP-TCA may be effective for patients with HCC after liver transplantation.

[Clinical study of prophylactic use of gentamicin and metronidazole in the surgery of colorectal carcinoma]

From Oct. 1989 to Apr. 1990, 16 patients with colorectal carcinoma undergoing elective radical resection were randomly divided into two groups to receive oral and combined (oral + i.v.) antimicrobials respectively. Patients in the oral group received preoperative oral gentamicin and metronidazole for two days, in the combined group oral medication was followed by the same antimicrobials intravenously during perioperative period. Quantitative bacterial cultures were performed before and after the regimen. Results showed that the preoperative prophylaxis with oral antimicrobial resulted in a significant reduction in the bacterial counts of the rectum contents in all the patients (P < 0.001). The NICs of gentamicin and metronidazole for E. coli and B. fragilis were found to be 2.31 micrograms/ml and 0.66 micrograms/ml respectively. The perioperative blood samples and the intraoperative tissue specimens were taken for gentamicin and metronidazole determination. In the oral group, effective concentration of metronidazole were found in serum and tissues but gentamicin was undetected. In the combined group, effective concentrations of both gentamicin and metronidazole were detected. According to our results, the short-term preoperative oral medications combined with perioperative intravenous gentamicin and metronidazole prophylaxis appears to rational.

[The mechanical stapler in rectal carcinoma]

Forty rectal carcinoma subjected to anterior resection using GF stapler during November 1979-March 1983 were reviewed. 32 were radical resections with the remaining 8 for palliation. 36 (90%) could be traced. 23/32 (73%) of the radical resection group survived for more than 5 years. Long-term follow-up showed that neither local recurrence nor 5 year survival was stapler-related. A stapler may facilitate the performance of a low anterior resection, but it is merely a form of technical improvement. Therefore, the principles of radical resection should still be strictly observed and indications for anterior resection should not be unconditionally extended.

Use of staplers on oesophagogastric varices

Thirty-five gastrofundic devascularization procedures were performed with the side-to-side CF stapler of Chinese manufacture for obliteration of oesophagogastric varices. Four patients were operated on as emergencies, six patients 2-3 weeks after control of bleeding by tamponade and the remaining twenty-five electively (including four patients who had not bled). There were two operative deaths, an operative mortality of 6 per cent. In all, 30 patients have been followed, 20 for 1-3 years and 10 for less than 1 year. Twenty-five patients had postoperative barium meal examination. The varices were ameliorated in 19, not changed in 5 and exacerbated in 1. Nine patients rebled and of these, two died. The stapler is used in devascularization to interrupt intramural varices in the oesophagocardiac region. It must be emphasized that its use is only a part of the devascularization procedure. When used alone devascularization is not complete. The side-to-side stapler appears to be a convenient, safe and rational instrument for use in devascularization.