Research on aiming methods for small sample size shooting tests of two-dimensional trajectory correction fuse

The longitudinal dispersion of the projectile in shooting tests of two-dimensional trajectory corrections fused with fixed canards is extremely large that it sometimes exceeds the correction ability of the correction fuse actuator.The impact point easily deviates from the target,and thus the correction result cannot be readily evaluated.However,the cost of shooting tests is considerably high to conduct many tests for data collection.To address this issue,this study proposes an aiming method for shooting tests based on small sample size.The proposed method uses the Bootstrap method to expand the test data;repeatedly iterates and corrects the position of the simulated theoretical impact points through an improved compatibility test method;and dynamically adjusts the weight of the prior distribution of simulation results based on Kullback-Leibler divergence,which to some extent avoids the real data being"submerged"by the simulation data and achieves the fusion Bayesian estimation of the dispersion center.The experimental results show that when the simulation accuracy is sufficiently high,the proposed method yields a smaller mean-square deviation in estimating the dispersion center and higher shooting accuracy than those of the three comparison methods,which is more conducive to reflecting the effect of the control algorithm and facilitating test personnel to iterate their proposed structures and algorithms.;in addition,this study provides a knowledge base for further comprehensive studies in the future.

Contract Mechanism of Water Environment Regulation for Small and Medium Sized Enterprises Based on Optimal Control Theory

The small and scattered enterprise pattern in the county economy has formed numerous sporadic pollution sources, hindering the centralized treatment of the water environment, increasing the cost and difficulty of treatment. How enterprises can make reasonable decisions on their water environment behavior based on the external environment and their own factors is of great significance for scientifically and effectively designing water environment regulation mechanisms. Based on optimal control theory, this study investigates the design of contractual mechanisms for water environmental regulation for small and medium-sized enterprises. The enterprise is regarded as an independent economic entity that can adopt optimal control strategies to maximize its own interests. Based on the participation of multiple subjects including the government, enterprises, and the public, an optimal control strategy model for enterprises under contractual water environmental regulation is constructed using optimal control theory, and a method for calculating the amount of unit pollutant penalties is derived. The water pollutant treatment cost data of a paper company is selected to conduct empirical numerical analysis on the model. The results show that the increase in the probability of government regulation and public participation, as well as the decrease in local government protection for enterprises, can achieve the same regulatory effect while reducing the number of administrative penalties per unit. Finally, the implementation process of contractual water environmental regulation for small and medium-sized enterprises is designed.

In-Situ Measuring the Particle Mean Size and Dust Concentration by Near-Forward Small Angle Light Scattering

本文综合前向小角光散理论及消光原理，提出一种测量粉尘平均粒径及粉尘浓度的光学方法．该方法测量透过粉尘的散射光在前向两个空间立体角内的光强及出射光强，可以方便地计算出粉尘的平均粒径及粉尘浓度的大小．实验结果表明该方法可作为一种在线的测尘方法．

Reliability Assessment for the Solenoid Valve of a High-Speed Train Braking System under Small Sample Size

Reliability assessment of the braking system in a high?speed train under small sample size and zero?failure data is veryimportant for safe operation. Traditional reliability assessment methods are only performed well under conditions of large sample size and complete failure data,which lead to large deviation under conditions of small sample size and zero?failure data. To improve this problem,a new Bayesian method is proposed. Based on the characteristics of the solenoid valve in the braking system of a high?speed train,the modified Weibull distribution is selected to describe the failure rate over the entire lifetime. Based on the assumption of a binomial distribution for the failure probability at censored time,a concave method is employed to obtain the relationships between accumulation failure prob?abilities. A numerical simulation is performed to compare the results of the proposed method with those obtained from maximum likelihood estimation,and to illustrate that the proposed Bayesian model exhibits a better accuracy for the expectation value when the sample size is less than 12. Finally,the robustness of the model is demonstrated by obtaining the reliability indicators for a numerical case involving the solenoid valve of the braking system,which shows that the change in the reliability and failure rate among the di erent hyperparameters is small. The method is provided to avoid misleading of subjective information and improve accuracy of reliability assessment under condi?tions of small sample size and zero?failure data.

Small for size syndrome difficult dilemma: Lessons from 10 years single centre experience in living donor liver transplantation

AIM To analyze the incidence, risk factors, prevention, treatment and outcome of small for size syndrome(SFSS) after living donor liver transplantation(LDLT). METHODS Through-out more than 10 years: During the period from April 2003 to the end of 2013, 174 adult-to-adults LDLT(A-ALDLT) had been performed at National Liver Institute, Menoufiya University, Shibin Elkoom, Egypt. We collected the data of those patients to do this cohort study that is a single-institution retrospective analysis of a prospectively collected database analyzing the incidence, risk factors, prevention, treatment and outcome of SFSS in a period started from the end of 2013 to the end of 2015. The median period of follow-up reached 40.50 m, range(0-144 m). RESULTS SFSS was diagnosed in 20(11.5%) of our recipients. While extra-small graft [small for size graft(SFSG)], portal hypertension, steatosis and left lobe graft were significant predictors of SFSS in univariate analysis(P = 0.00, 0.04, 0.03, and 0.00 respectively); graft size was the only independent predictor of SFSS on multivariate analysis(P = 0.03). On the other hand, there was lower incidence of SFSS in patients with SFSG who underwent splenectomy [4/10(40%) SFSS vs 3/7(42.9%) no SFSS] but without statistical significance, However, there was none significant lower incidence of the syndrome in patients with right lobe(RL) graft when drainage of the right anterior and/or posterior liver sectors by middle hepatic vein, V5, V8, and/or right inferior vein was done [4/10(28.6%) SFSS vs 52/152(34.2%) no SFSS]. The 6-mo, 1-, 3-, 5-, 7-and 10-year survival in patients with SFSS were 30%, 30%, 25%, 25%, 25% and 25% respectively, while, the 6-mo, 1-, 3-, 5-, 7-and 10-year survival in patients without SFSS were 70.1%, 65.6%, 61.7%, 61%, 59.7%, and 59.7% respectively, with statistical significant difference(P = 0.00). CONCLUSION SFSG is the independent and main factor for occurrence of SFSS after A-ALDLT leading to poor outcome. However, the management of this catastrophe depends upon its prevention(i.e., selecting graft with proper size, splenectomy to decrease portal venous inflow, and improving hepatic vein outflow by reconstructing large draining veins of the graft).

Stability of the Dividing Distribution Function Method for ParticleSize Distribution Analysis in Small Angle X－Ray Scattering

The Dividing Distribution Function (DDF) method is one of the methods by which the particle size distribution of ultrafine powder can be evaluated from its small angle X-ray scattering data. In this paper, the stability of the solution obtained from DDF method has been investigated through optimizing the coefficient matrix, introducing a damping factor and a least square treatment. All calculations were accomplished with a microcomputer. It was shown that the average deviations of the size distribution obtained are not larger than the assigned random errors to the scattering intensities as long as the corresponding requirements are satisfied.

Polymorphism of BMPR-IB Gene and its Relationship with Litter Size in Small Tail Han Sheep

[ Objective] To open an exit for breeding high-fecundity Small Tail Han sheep according to genotypes. [ Method] By the PCR-RFLP, the polymorphism of ovine BMPR-IB gene was detected in Small Tail Han sheep of basic population and breeding population. And its relationship with litter size was analyzed. [ Result] In the basic population, the frequencies of B ＋ and BB genotypes were 77.78% and 14.81%, respectively, and their litter size per parity was 1.77 and 2.40, respectively. In the breeding population, the frequencies of B ＋ and BB genotypes were 51.79% and 40.18%, respectively, and their litter size per parity was 2.54 and 3.02, respectively. [ Conclusion] The ovine BMPR-IB gene can be used as a molecular Qenetic marker for fecundity traits to establish high-fecundity Small Tail Han sheep.

Impact of small-for-size liver grafts on medium-term and long-term graft survival in living donor liver transplantation: A meta-analysis

BACKGROUND Small-for-size grafts (SFSGs) in living donor liver transplantation (LDLT) could optimize donor postoperative outcomes and also expand the potential donor pool. Evidence on whether SFSGs would affect medium-term and long-term recipient graft survival is lacking. AIM To evaluate the impact of small-for-size liver grafts on medium-term and longterm graft survival in adult to adult LDLT. METHODS A systematic review and meta-analysis were performed by searching eligible studies published before January 24, 2019 on PubMed, EMBASE, and Web of Science databases. The primary outcomes were 3-year and 5-year graft survival. Incidence of small-for-size syndrome and short term mortality were also extracted. RESULTS This meta-analysis is reported according to the guidelines of the PRISMA 2009 Statement. Seven retrospective observational studies with a total of 1821 LDLT recipients were included in the meta-analysis. SFSG is associated with significantly poorer medium-term graft survival. The pooled odds ratio for 3-year graft survival was 1.58 [95% confidence interval 1.10-2.29, P = 0.014]. On the other hand, pooled results of the studies showed that SFSG had no significant discriminatory effect on 5-year graft survival with an odds ratio of 1.31 (95% confidence interval 0.87-1.97, P = 0.199). Furthermore, incidence of small-for-size syndrome detected in recipients of SFSG ranged from 0-11.4% in the included studies. CONCLUSION SFSG is associated with inferior medium-term but not long-term graft survival. Comparable long-term graft survival based on liver graft size shows that smaller grafts could be accepted for LDLT with appropriate flow modulatory measures. Close follow-up for graft function is warranted within 3 years after liver transplantation.

Industrial Preparation and Acid Resistance of Ultra-stable Y Zeolite with Small Cell Size Produced by Gas-phase Method

Small-cell HSY-S zeolite prepared by the gas-phase ultra-stable method had been researched and developed,and industrial preparation tests of HSY-S have been successfully carried out for the first time.The acid resistance of industrially prepared HSY-S was investigated by acid solutions with different pH values.The structures and properties of HSY-S and its acid-treated samples were characterized by XRD,XRF,BET,and IR.Results show that the HSY-S samples have the characteristics of high crystallinity,good stability,large specific surface area,and good acid resistance.

Outcome of patients undergoing right lobe living donor liver transplantation with small-for-size grafts

AIM:To investigate the outcome of living donor liver transplantation(LDLT)recipients transplanted with small-for-size grafts(SFSGs).METHODS:Between November 2001 and December2010,196 patients underwent LDLT with right lobe liver grafts at our center.Recipients were divided into 2 treatment groups:group A with an actuarial graft-to-recipient weight ratio(aGRWR)<0.8%(n=45)and group B with an aGRWR≥0.8%(n=151).We evaluated serum liver function markers within 4 wk after transplantation.We also retrospectively evaluated the outcomes of these patients for potential effects related to the recipients,the donors and the transplantation procedures based upon a review of their medical records.RESULTS:Small-for-size syndrome(SFSS)developed in 7 of 45 patients(15.56%)in group A and 9 of 151patients(5.96%)in group B(P=0.080).The levels of alanine aminotransferase and aspartate aminotransferase in group A were higher than those in group B during early period after transplantation,albeit not significantly.The cumulative 1-,3-and 5-year liver graft survival rates were 82.22%,71.11%and 71.11%for group A and 81.46%,76.82%,and 75.50%for group B patients,respectively(P=0.623).However,univariate analysis of risk factors associated with graft survival in group A demonstrated that the occurrence of SFSS after LDLT was the only significant risk factor affecting graft survival(P<0.001).Furthermore,multivariate analysis of our data did not identify any additional significant risk factors accounting for poor graft survival.CONCLUSION:Our study suggests that LDLT recipients with an aGRWR<0.8%may have liver graft outcomes comparable to those who received larger size grafts.Further studies are required to ascertain the safety of using SFSGs.

Should temporary extracorporeal continuous portal diversion replace meso/porta-caval shunts in “small-for-size” syndrome in porcine hepatectomy?

AIM:To investigate the feasibility of temporary extracorporeal continuous porta-caval diversion(ECPD) to relieve portal hyperperfusion in "small-for-size" syndrome following massive hepatectomy in pigs.METHODS:Fourteen pigs underwent 85%-90% liver resection and were then randomly divided into thecontrol group(n = 7) and diversion group(n = 7).In the diversion group,portal venous blood was aspirated through the portal catheter and into a tube connected to a centrifugal pump.After filtration,the blood was returned to the pig through a double-lumen catheter inserted into the internal jugular or subclavian vein.With the conversion pump,portal venous inflow was partially diverted to the inferior vena cava through a catheter inserted via the gastroduodenal vein at 100-130 m L/min.Portal hemodynamics,injury,and regeneration in the liver remnant were compared between the two groups.RESULTS:Compared to the control group,porta-caval diversion via ECPD significantly mitigated excessive portal venous flow and portal vein pressure(PVP); the portal vein flow(PVF),hepatic artery flow(HAF),and PVP in the two groups were not significantly different at baseline; however,the PVF(431.8 ± 36.6 vs 238.8 ± 29.3,P < 0.01; 210.3 ± 23.4 vs 122.3 ± 20.6,P < 0.01) and PVP(13.8 ± 2.6 vs 8.7 ± 1.4,P < 0.01; 15.6 ± 2.1 vs 10.1 ± 1.3,P < 0.05) in the control group were significantly higher than those in the diversion group,respectively.The HAF in the control group was significantly lower than that in the diversion group at 2 h and 48 h post hepatectomy,and ECPD significantly attenuated injury to the sinusoidal lining and hepatocytes,increased the regeneration index of the liver remnant,and relieved damage that the liver remnant suffered due to endotoxin and bacterial translocation.CONCLUSION:ECPD,which can dynamically modulate portal inflow,can reduce injury to the liver remnant and facilitate liver regeneration,and therefore should replace permanent meso/porta-caval shunts in "smallfor-size" syndrome.

Numerical investigation on the flow and power of small-sized multi-bladed straight Darrieus wind turbine

Straight Darrieus wind turbine has attractive characteristics such as the ability to accept wind from random direction and easy installation and maintenance. But its aerodynamic performance is very complicated,especially for the existence of dynamic stall. How to get better aerodynamic performance arouses lots of interests in the design procedure of a straight Darrieus wind turbine. In this paper,mainly the effects of number of blades and tip speed ratio are discussed. Based on the numerical investigation,an assumed asymmetric straight Darrieus wind turbine is proposed to improve the averaged power coefficient. As to the numerical method,the flow around the turbine is simulated by solving the 2D unsteady Navier-Stokes equation combined with continuous equation. The time marching method on a body-fitted coordinate system based on MAC (Marker-and-Cell) method is used. O-type grid is generated for the whole calculation domain. The characteristics of tangential and normal force are discussed related with dynamic stall of the blade. Averaged power coefficient per period of rotating is calculated to evaluate the eligibility of the turbine.

Small-for-size syndrome in living donor liver transplantation

When the graft volume is too small to satisfy the recipient’s metabolic demand, the recipient may thus experience small-for-size syndrome (SFSS). Because the occurrence of SFSS is determined by not only the liver graft volume but also a combination of multiple negative factors, the definitions of small-for-size graft (SFSG) and SFSS are different in each institute and at each time. In the clinical setting, surgical inflow modulation and maximizing the graft outflow are keys to overcoming SFSS. Accordingly, relatively smaller-sized grafts can be used with surgical modification and pharmacological manipulation targeting portal circulation and liver graft quality. Therefore, the focus of the SFSG issue is now shifting from how to obtain a larger graft from the living donor to how to manage the use of a smaller graft to save the recipient, considering donor safety to be a priority.

Extended hepatectomy with segments Ⅰand Ⅶ as resection remnant:a simple model for small-for-size injuries in pigs

BACKGROUND:Small-for-size(SFS)syndrome is an important clinical problem after living donor liver transplantation,split liver transplantation or extended hepatectomy.The uncertainty of the mechanisms and treatments of SFS syndrome urges surgeons to establish effective models for SFS syndrome. METHODS:A new porcine model for SFS syndrome based on extended hepatectomy was established.Portal pressure gradient was observed before and after the surgery,and venous sampling for estimation of alanine aminotransferase, total bilirubin,and international normalized ratio was continued on a daily basis. RESULTS:Although the external morphology of the porcine liver differs from that of human being,segmental anatomy is remarkably similar in term of its vascularity and biliary tree.Extended hepatectomy with segmentsⅠand Ⅶas resection remnant(about 20%of total liver volume) resulted in similar survival rates,blood liver function tests,and elevated portal pressure gradient as clinical SFS syndrome. CONCLUSIONS:The extended hepatectomy based new model can easily be reproduced,with few costs and surgical complications.Clinical SFS syndrome can easily be simulated by this new model,which is a useful tool for studying SFS syndrome-related liver injuries,especially portal overperfusion and hypertension.

Small-for-size syndrome in adult-to-adult living-related liver transplantation

Small-for-size syndrome (SFSS) in adult-to-adult living-related donor liver transplantation (LRLT) remains the greatest limiting factor for the expansion of segmental liver transplantation from either cadaveric or living donors. Portal hyperperfusion, venous pathology, and the arterial buffer response signif icantly contribute to clinical and histopathological manifestations of SFSS. Here, we review the technical aspects of surgical and radiological procedures developed to treat SFSS in LRLT, along with the pathophysiology of this condition.

Tacrolimus dosage requirements in living donor liver transplant recipients with small-for-size grafts

AIM:To investigate the tacrolimus dosage requirements and blood concentrations in adult-to-adult right lobe living donor liver transplantation (AALDLT) recipients with small-for-size (SFS) grafts.METHODS: During January 2007 and October 2008, a total of 54 cases of AALDLT with an observation period of 6 mo were enrolled in this study. The 54 patients were divided into two groups according to graft-recipient body weight ratio (GRBW): SFS grafts group (Group S, GRBW<0.8%, n=8) and non-SFS grafts group (Group N, GRBW ≥0.8%, n=46). Tacrolimus 12-hour blood levels and doses were recorded during weeks 1,2,3 and 4 and months 2,3,4,5 and 6 in group S and group N. Meanwhile, acute rejection rates, liver and renal function test results, and the number of potentially interacting medications were determined at each interval in the two groups. A comparison of tacrolimus dosage requirements and blood levels were made weekly in the first month post-surgery, and monthly from months 2 to 6.RESULTS: There were no differences in the demo-graphic characteristics, acute rejection rates, liver and renal function test results, or the number of potentially interacting medications administered between the two groups. The tacrolimus dosage requirements in group S were significantly lower than group N at 2 wk (2.8±0.4 mg/d vs 3.6±0.7 mg/d, P=0.006), 3 wk (2.9±0.7 mg/d vs 3.9±0.8 mg/d, P=0.008), 4 wk (2.9±0.8 mg/d vs 3.9±1.0 mg/d, P=0.023) and 2 mo (2.8±0.7 mg/d vs 3.8 ±1.1 mg/d, P=0.033). Tacrolimus 12-h trough concentrations were similar between the two groups at all times except for 2 wk post-transplantation, when the concentrations were signifi cantly greater in group S recipients than in group N recipients (11.3±4.8 ng/mL vs 7.0±3.8 ng/mL, P=0.026).CONCLUSION: SFS grafts recipients have signifi cantly decreased tacrolimus dosage requirements compared with non-SFS grafts recipients in AALDLT during the first 2 mo post-surgery.

Extracorporeal continuous portal diversion plus temporal plasmapheresis for “small-for-size” syndrome

AIM:To investigate the effect of plasmapheresis via the portal vein for"small-for-size"syndrome(SFSS)aided by extracorporeal continuous portal diversion(ECPD).METHODS:Extensive or total hepatectomy in the pig is usually adopted as a postoperative liver failure(PLF)or SFSS model.In this study,animals which underwent85%-90%hepatectomy were randomized into either the Systemic group(n=7)or the Portal group(n=7).In the Systemic group,all pigs received temporal plasmapheresis(PP)via the extracorporeal catheter circuit(systemic to systemic circulation)from 24 to 30 h posthepatectomy(PH);in the Portal group,all pigs received ECPD to divert partial portal vein flow(PVF)to the systemic circulation after hepatectomy,then converted to temporal PP from 24 to 30 h PH,and subsequently converted to ECPD again until 48 h PH.In the Portal group,the PVF was preserved at 3.0-3.3 times that of the baseline value,similar to that following 70%hepatectomy,which was regarded as the optimal PVF to the hypertrophic liver remnant.At 48 h PH,all pigs were re-opened and the portal vein pressure(PVP),PVF,and HAF(hepatic artery flow)were measured,and then diversion of the portal venous flow was terminated.After1 h the PVP,PVF,and HAF were re-measured.The portal hemodynamic changes,liver injury,liver regeneration and bacterial/lipopolysaccharide(LPS)translocation were evaluated in the two groups.RESULTS:The PVP in the Portal group was significantly lower than that in the Systemic group during the time period from 2 to 49 h PH(P<0.05).Serum alanine aminotransferase(ALT),total bilirubin(TB)and ammonia were significantly reduced in the Portal group compared with the Systemic group from 24 to 48 h PH(P<0.05).The Portal group may have attenuated sinusoidal endothelial injury and decreased the level of HA compared with the Systemic group.In the Systemic group,there was significant sinusoidal dilation,hydropic changes in hepatocytes and hemorrhage into the hepatic parenchyma,and the sinusoidal endothelial lining was partially destroyed and detached into the sinusoidal space.CD31immunostaining revealed significant destruction of the endothelial lining.In the Portal group,there was no intraparenchymal hemorrhage and the sinusoidal endothelial cells and hepatocytes were well preserved.CD31immunostaining was mild which indicated less destruction of the endothelial lining.HA was significantly decreased in the Portal group compared with the Systemic group from 2 to 48 h PH.The rate of liver remnant regeneration was elevated,while apoptosis was attenuated in the Portal group compared with the Systemic group.Thymidine kinase activity was much higher in the Portal group than in the Systemic group at 48 h PH.The PCNA index was significantly increased and the apoptotic index was significantly decreased in the Portal group compared with the Systemic group.Bacterial translocation and endotoxin,as well as the inflammatory response,were significantly attenuated in the Portal group compared with the Systemic group.LPS,tumor necrosis factor-and interleukin-6 levels were all significantly decreased in the Portal group compared with the Systemic group from 24 to48 h PH,while bacterial DNA level was significantly decreased from 2 to 48 h PH.CONCLUSION:PP plus ECPD via the portal vein can attenuate toxic load and hyperperfusion injury,and should be undertaken instead of PP via the systemic circulation in SFSS or PLF.

Expression of iNOS in early injury in a rat model of small-for-size liver transplantation

BACKGROUND: Living donor liver transplantation has been widely accepted as the treatment of choice for end-stage liver disease. Large amounts of nitric oxide generated by inducible nitric oxide synthase (iNOS) have been shown to play an important role in many inflammatory and immune reactions, but expression of iNOS in small-for-size liver transplantation is unknown. The aims of this study were to determine the time course of iNOS mRNA and protein as well as the redox state of liver biopsies in a rat model of small-for-size liver transplantation. METHODS: Male Sprague-Dawley rats were divided into a control group, a warm ischemia-reperfusion (IR) group, and a small-for-size liver graft group. Real-time RT-PCR and Western blotting were used to characterize the time course of the expression of iNOS mRNA and protein, respectively. Malondialdehyde (MDA) and superoxide dismutase (SOD) were used as markers to characterize the redox state of liver tissues, and the time courses of MDA and SOD levels were also measured. RESULTS: The expression of iNOS mRNA and protein levels in the warm IR and small-for-size graft groups both significantly increased after reperfusion, and peaked at 3 hours. Moreover, the increase in MDA was accompanied by increased iNOS in the period of 1-24 hours after reperfusion. The MDA levels in the warm IR and small-for-size graft groups significantly increased after reperfusion, peaked at 3 hours, and decreased thereafter. The direction of change in SOD was opposite that of the change in MDA. CONCLUSIONS: The expression of iNOS mRNA and protein is activated after reperfusion both in hepatic warm IR injury and small-for-size liver graft. Furthermore, the results of this study suggest that iNOS contributes to the damage in warm IR injury and small-for-size grafts via free oxygen radicals.

Excessive portal flow causes graft failure in extremely small-for-size liver transplantation in pigs

AIM: To evaluate the effects of a portocaval shunt on the decrease of excessive portal flow for the prevention of sinusoidal microcirculatory injury in extremely smallfor-size liver transplantation in pigs.METHODS: The right lateral lobe of pigs, i.e. the 25%of the liver, was transplanted orthotopically. The pigs were divided into two groups: graft without portocaval shunt (n = 11) and graft with portocaval shunt (n=11).Survival rate, portal flow, hepatic arterial flow, and histological findings were investigated.RESULTS: In the group without portocaval shunt, all pigs except one died of liver dysfunction within 24 h after transplantation. In the group with portocaval shunt,eight pigs survived for more than 4 d. The portal flow volumes before and after transplantation in the group without portocaval shunt were 118.2±26.9 mL/min/100 g liver tissue and 270.5±72.9 mL/min/100 g liver tissue,respectively. On the other hand, in the group with portocaval shunt, those volumes were 124.2±27.8 mL/min/100 g liver tissue and 42.7±32.3 mL/min/100 g liver tissue, respectively (P＜0.01). As for histological findings in the group without portocaval shunt, destruction of the sinusoidal lining and bleeding in the peri-portal areas were observed after reperfusion, but these findings were not recognized in the group with portocaval shunt.CONCLUSION: These results suggest that excessive portal flow is attributed to post transplant liver dysfunction after extreme small-for-size liver transplantation caused by sinusoidal microcirculatory injury.

Outcomes of right-lobe and left-lobe living-donor liver transplantations using small-for-size grafts

AIM To analyze the outcomes of living-donor liver transplantation(LDLT) using left-lobe(LL) or right-lobe(RL) small-for-size(SFS) grafts.METHODS Prospectively collected data of adult patients who underwent LDLT at our hospital in the period from January 2003 to December 2013 were reviewed. The patients were divided into the RL-LDLT group and the LL-LDLT group. The two groups were compared in terms of short-and long-term outcomes, including incidence of postoperative complication, graft function, graft survival, and patient survival. A SFS graft was defined as a graft with a ratio of graft weight(GW) to recipient standard liver volume(RSLV)(GW/RSLV) of < 50%. The Urata formula was used to estimate RSLV.RESULTS Totally 218 patients were included for analysis, with 199 patients in the RL-LDLT group and 19 patients in the LL-LDLT group. The two groups were similar in terms of age(median, 53 years in the RL-LDLT group and 52 years in the LL-LDLT group, P = 0.997) but had significantly different ratios of men to women(165:34 in the RL-LDLT group and 8:11 in the LL-LDLT group, P < 0.0001). The two groups were also significantly different in GW(P < 0.0001), GW/RSLV(P < 0.0001), and graft cold ischemic time(P = 0.007). When it comes to postoperative complication, the groups were comparable(P = 0.105). Five patients died in hospital,4(2%) in the RL-LDLT group and 1(5.3%) in the LLLDLT group(P = 0.918). There were 38 graft losses, 33(16.6%) in the RL-LDLT group and 5(26.3%) in the LL-LDLT group(P = 0.452). The 5-year graft survival rate was significantly better in the RL-LDLT group(95.2% vs 89.5%, P = 0.049). The two groups had similar 5-year patient survival rates(RL-LDLT: 86.8%, LL-LDLT: 89.5%, P = 0.476).CONCLUSION The use of SFS graft in LDLT requires careful tailormade surgical planning and meticulous operation. LLLDLT can be a good alternative to RL-LDLT with similar recipient outcomes but a lower donor risk. Further research into different patient conditions is needed in order to validate the use of LL graft.