Conventional static cold storage (SCS) exacerbates ischemic injury in the DCD liver, leading to severe complications for transplant recipients. To address this issue, clinical application of MP technology for donor liver preservation is underway. Simultaneously, efforts are focused on the development of various MP instruments, validated through relevant animal model experiments. Effective large animal trials play a pivotal role in clinical applications. However, challenges persist in the ex vivo preservation of DCD livers and the transplantation procedure in pigs. These hurdles encompass addressing the prolonged preservation of donor livers, conducting viability tests, alleviating ischemic injuries, and shortening the anhepatic phase. The use of a variable temperature-controlled MP device facilitates the prolonged preservation of DCD livers through sequential Dual Hypothermic Oxygenated Machine Perfusion (DHOPE) and Normothermic Machine Perfusion (NMP) modes. This protocol enhances the porcine OLTx model by improving the quality of DCD livers, optimizing the anastomosis technique, and reducing the duration of the anhepatic phase.

Introduction: For end-stage liver diseases, liver transplantation remains the most suitable therapy for its treatment. Nonetheless, the current gap between the patients on the waiting list and the graft supply, as well as the gold standard preservation method (Static Cold Storage or SCS), limits its usefulness. Extended Criteria Donors (ECD) has been proposed as a potential solution to increase the donor pool, although these have a greater susceptibility to ischemia-reperfusion injury (IRI), especially after SCS, causing delayed graft function and primary non-function. These side effects have fueled research into more suitable methods such as ex-situ normothermic machine perfusion (NMP). Methods: Sixteen healthy pig livers were subjected to normothermic perfusion using blood as a perfusion solution. in 5 experiments, taurocholic acid was administrated 6 hours after perfusion initiation. Perfusate and bile were sampled before, during and after perfusion to assess the hepatocellular injury and liver function and bile duct injury and bile production. Liver samples were collected before and after perfusion to perform analysis of general damage, stellate cell activation, oxidative stress and LSEC response. Results: AST and LDH levels increased progressively for the first 12 hours (P= 0.02 and P=0.001 respectively). Afterward, both parameters stabilized. Glucose and lactate levels decreased rapidly during the first 4 hours (p=0.003 for glucose and p=0.04 for lactate) and reached the lowest within 8 (p<0.001) and 12 hours (p<0.001) respectively. Overall, blood pH remained steady (p=0.10). Serum levels of ALKP, GGT and Bil didn’t suffer any changes during all the perfusion (p=0.99, p=0.75 and p=0.13 respectively). Bile production started within 1 hour after ex-situ perfusion. Livers supplied with taurocholic acid had a higher bile production rate, 9±3 mL/h, compared to those not supplied, 4±3 (p=0.005). No structural alterations were detected in liver samples after the Suzuki injury score assessment (p=0.33) and stellate cell activation quantification by both gene (p=0,64) and protein expression (p=0,79) and percentage of the stained area (p=0.15). Although eNOS gene and protein expression increased (p=0.01 and p=0.008 respectively), histological analysis of CD31 endothelial staining showed no differences between the baseline, 35,7±9,1 %, and the 24-hour perfusion 36,3±7,2%, of the sinusoidal area (p=0.87). This increase was associated with higher levels of MDA after the perfusion (p=0.006) as the KLF2 gene and protein expression remained invariable (p=0.80 and p=0.26 respectively). Conclusion: Our results show that NMP, as a preservation method, is capable of maintaining the normal hepatic structure and, at the same time, supporting normal metabolic activity. However, further studies should be conducted to demonstrate post-transplant liver viability.

Amelia Hessheimer, Xiran He, Mingju Liang, Javier Muñoz, Josep M. Sanahuja, Xiaoyu Tan, Marina Vendrell, Felipe León, I sabel Mora, Joaquím Albiol, Li Lin, Feng Huo, Constantino Fondevila Hospital Clínic i Provincial, Barcelona, Spain; Guanguong Shunde Innovative Design Institute, Guangdong, People’s Republic of China; General Hospital of Southern Theater Command of PLA, Guangdong, People’s Republic of China; DTI Foundation, Barcelona, Spain.

目的:探讨自主研发的离体肝脏双泵双氧合机械灌注设备DEVOCEAN-LIVER 2000在离体猪肝脏常温机械灌注上的安全性与可操作性.方法:从45～50 kg雌性巴马小型猪获取供肝,使用DEVOCEAN-LIVER 2000,采用恒压模式对动脉和门静脉进行常温机械灌注6 h,使用雅培iSTAT-300G血气分析仪对每小时的灌注液进行分析,同时利用微纳芯Pointcare V2对灌注液进行生化检测.实时记录并比较灌注过程中动脉和门静脉流量、动脉血液pH值、胆汁生成量、转氨酶、血糖、乳酸、总胆红素的变化.灌注前后,切取肝脏组织制作病理切片,观察肝脏组织形态的变化.采用SPSS 23.0统计学软件进行实验数据分析.结果:灌注过程中,动脉流量及门静脉流量随灌注时间平稳增长;动脉血液pH值一直维持在7.2～7.5;胆汁持续性生成,最高峰可达0.0085 mL/[h·g(肝重)];灌注液中的谷丙转氨酶(ALT)和谷草转氨酶(AST)小幅增加;血糖总体呈现平稳下降状态;乳酸水平整体呈下降趋势,灌注前与灌注6 h的乳酸水平相比差异有统计学意义(P<0.05);灌注前后胆红素变化不明显(P>0.05).灌注结束后,肝脏外观无明显瘀斑,显微镜下肝小叶结构完整.结论:DEVOCEAN-LIVER 2000能为肝脏提供6 h稳定的体外常温机械灌注,使肝脏在体外仍然保持活性,并且有效改善肝脏微循环,具有良好的安全性与可操作性.

目的:初步探索离体肝脏双泵双氧合机械灌注设备在离体猪肝脏低温灌注中的可操作性以及稳定性.方法:从45～50 kg雌性巴马小型猪获取供肝,利用灌注设备同时对肝动脉和门静脉实施低温携氧灌注8 h.肝动脉采用压力恒定模式控制,门静脉采用流量恒定模式控制,观察灌注过程中的流量、压力、血气指标、炎症因子以及病理组织学评分的变化.采用IBM SPSS Statistics 23.0统计学软件进行实验数据分析.结果:灌注过程中,肝动脉压力稳定维持在24.09～24.65 mmHg(1 mmHg=133.32 Pa),流量从初期的0.04 mL/[min·g(肝重)]逐渐升高至0.09 mL/[min·g(肝重)];门静脉的流量稳定维持在0.47～0.50 mL/[min·g(肝重)],压力呈降低趋势,从初期的2.79 mmHg下降至1.84 mmHg.灌注液pH值、葡萄糖(Glu)以及乳酸(Lac)水平维持稳定.肝组织的炎症因子白介素6(IL-6)和肿瘤坏死因子α(TNF-α)亦维持稳定.在组织病理学评价方面,肝组织的空泡化水平呈下降趋势,而肝组织的坏死、水肿以及肝窦扩张水平则维持稳定.结论:该离体肝脏双泵双氧合机械灌注设备能够无故障地运转8 h,同时维持肝脏的低代谢状态,降低肝内灌注阻力和改善肝细胞缺氧,具有安全性和稳定性.

There is a dearth of effective parameters for selecting potentially transplantable liver grafts from expanded-criteria donors. In this study, we used a nuclear magnetic resonance (NMR) relaxation analyzer-based assay to assess the viability of ex vivo livers obtained via porcine donation after circulatory death (DCD). Ex situ normothermic machine perfusion (NMP) was utilized as a platform for viability test of porcine DCD donor livers. A liver-targeted contrast agent, gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA), was injected into the perfusate during NMP, and the dynamic biliary excretion of the Gd-EOB-DTPA was monitored by measuring the longitudinal relaxation time (T1). The longitudinal relaxation rate (R1) of the bile was served as a parameter. The delay of increase in biliary R1 during early stage of NMP indicated the impaired function of liver grafts in both warm and cold ischemia injury, which was correlated with the change of alanine aminotransferase. The preservative superiority in cold ischemia of dual hypothermic oxygenated machine perfusion could also be verified by assessing biliary R1 and other biochemical parameters. This study allows for the dynamic assessment of the viability of porcine DCD donor livers by combined usage of ex situ NMP and NMR relaxation time based assay, which lays a foundation for further clinical application.

目的 构建离体肝脏常温机械灌注设备,探讨灌注实验过程对红细胞的影响.方法 获取健康雌性巴马小型猪肝脏和血液,利用常温机械灌注设备对离体肝脏持续灌注8 h,温度设定37℃,动脉压力设定80/60 mmHg,门静脉设定恒流模式(0.5 mL/minrg),记录灌注过程中灌注液温度、肝动脉和门静脉流量等数据,每小时化验红细胞及其他相关指标,包括红细胞压积(Hematocrit,HCT)、血红蛋白(Hemoglobin,HGB)、总胆红素(Total Bilirubin,TBIL)、间接胆红素(Indirect Bilirubin,IBIL)、溶血率、乳酸(Lactate,Lac)以及血糖(Glucose,Glu).结果 灌注过程中灌注液温度稳定维持37℃,肝动脉流量从最初的(54.64±11.94)mL/min,上升到(249.34±93.01)mL/min,门静脉流量平均值稳定在(442.67±79.19)mL/min.灌注开始和结束时HCT和HGB分别为(27.67±2.42)％、(9.40±0.81)g/dL和(28.00±2.45)％、(9.52±0.81)g/dL.分别比较灌注开始和结束时HCT、HGB数值,均无统计学差异.灌注前后TBIL和IBIL水平比较,差异无统计意义.灌注过程中每小时检测溶血率均为0.Lac从灌注开始的(2.52±0.39)mmol/L下降至灌注结束的(0.35±0.07)mmol/L(P＜0.05).Glu在第2小时达到最高值(21.37±5.96)mmol/L,灌注结束时下降至(9.78±2.63)mmol/L(P＜0.05).结论 离体肝脏常温机械灌注设备能够维持HCT和HGB稳定,不会导致溶血;过程中Lac和Glu持续消耗,间接反映了灌注过程红细胞携氧能力可以改善离体肝脏功能.

目的 探讨自主研发的常温机械灌注(Normothermic Machine Perfusion,NMP)设备对不同热缺血时间下供肝的保护作用.方法 选取雌性巴马猪作为血液和肝脏供体,分为DCD30min组和DCD60min组,利用NMP设备灌注12 h,观察灌注过程中两组的灌注参数、血气生化指标以及胆汁相关指标的水平.结果 两组供肝不同时间点的肝动脉流量比较,差异无统计学意义(P＞0.05);DCD 30 min组的门静脉压力低于DCD 60 min组,差异有统计学意义(P＜0.05);两组的酸碱平衡、乳酸、血糖、ALP、γGGT和TBIL的水平比较,均无统计学意义(P＞0.05);DCD 60 min组的尿素氮水平更高,DCD 30 min组的转氨酶水平更低,均具有统计学差异(P＜0.05);两组肝脏均能持续合成胆汁,胆汁的pH、碳酸氢根及葡萄糖水平均无统计学差异(P＞0.05);而胆汁胆红素和胆汁酸浓度具有统计学差异(P＜0.05).结论 NMP12h,两组不同热缺血时间的供肝都能进行有氧代谢和持续合成胆汁,提示自主研发的NMP设备可有效保护有热缺血损伤的供肝.

为了推动动物实验教学的发展,提供巴马小型猪胆汁和血液生理生化指标等相关参考数据.选取健康合格的巴马小型猪17只,体重45～50 kg,使用血气分析仪和全自动生化分析仪检测麻醉状态下巴马小型猪术前的胆汁和动脉血气、生化等生理生化指标,并运用血液指标与相关文献和人类正常参考值作比较,使用SPSS23.0统计软件进行统计学分析.结果检测数据均呈正态分布,经比较,更多的血液生理生化指标在人的正常参考范围值内,表明实验数据具有一定的参考意义.

目的 探讨在体常温局部灌注对猪心脏死亡器官捐献(donation after cardiac death,DCD)肝脏的修复作用.方法 45 kg巴马小型猪(n=3)在麻醉后,分别经颈静脉、髂动脉插入导管并与体外膜肺氧合(extracorporeal membrane oxygenation,ECMO)连接.静脉注射氯化钾溶液引发心跳骤停,30 min后置入球囊导管阻断胸主动脉,开始运转设备进行在体常温(37℃)局部灌注4 h,静脉血氧维持在60%～70%,每隔1 h检测其血气、生化指标,灌注前、后取肝脏组织,进行病理观察.结果 4 h灌注过程中,设备运转稳定,乳酸显著下降(P<0.05),肝脏持续有胆汁生成,丙氨酸转氨酶、谷氨酰转肽酶及总胆红素浓度变化无统计学差异(P>0.05),天冬氨酸转氨酶在正常范围内,病理切片提示灌注前、后的病理评分差异极其显著(P<0.01).结论 本研究证明在体常温局部灌注对猪DCD30 min肝脏具有修复作用.

目的 利用离体肝脏常温灌注系统初步探索门静脉恒压控制模式与门静脉恒流控制模式对热缺血损伤肝脏的保存效果差异.方法 使用雌性巴马小型猪获取血液和供肝,所有供肝的热缺血时间为60 min,一组采用门静脉恒压控制模式(n=6),一组采用门静脉恒流控制模式(n=6),利用常温机械灌注设备灌注6 h,观察肝脏的灌注参数、血气生化指标以及组织病理学变化.结果 灌注前,两组的冷缺血时间差异无统计学意义(P>0.05).猪肝脏经过6 h的常温机械灌注,恒压组的肝动脉流量为(0.13±0.08)mL/min/g(肝重)比恒流组的(0.25±0.09)mL/min/g(肝重)更低(P<0.05).两组比较,灌注液的pH、乳酸水平、葡萄糖水平差异无统计学意义(P>0.05);尿素氮水平除了在第2小时,两组比较差异无统计学意义(P>0.05).对于肝细胞酶学和总胆红素水平,两组在灌注结束时亦差异无统计学意义(P>0.05).恒流组的胆汁生成量为(54.47±15.63)mL,较恒压组的(6.98±3.20)mL更多(P<0.05).两组在病理学评分的比较差异无统计学意义(P>0.05).结论 门静脉恒流模式更有利于肝动脉的供血,从而促进肝细胞进行胆汁合成,提示门静脉流量控制模式可能是更合适的灌注方式.但是这仍需要通过动物肝移植实验以及临床肝移植的数据进一步验证.

目的 探讨便携式在体机械灌注设备(IMPD)运行稳定性和保护无心跳大动物供器官的作用.方法 6只健康清洁巴马小型猪麻醉后开腹,分别经腹主动脉、下腔静脉插管并连接到自主研发的便携式IMPD,静脉注射氯化钾骤停心脏,观察5 min无复跳,启动设备对动物器官进行常温(37℃)机械灌注.调整离心泵转速和灌注流量以控制静脉血氧饱和度维持在60％ ～70％,持续灌注12 h,每2小时为观察时间点,记录设备管路流量、离心泵转速和流量/转速比值,检测肝、肾功能和血液内环境指标,灌注结束后获取胆总管、肝、肾和小肠组织,HE染色后光镜下评估病理改变情况.采用重复测量资料单因素方差分析比较灌注过程中各时间点运行参数、肝肾功能和血液内环境指标,组内两两比较采用LSD法,P<0.05为差异有统计学意义.结果 全部实验均完成12 h灌注,灌注过程中设备运行稳定,无故障或停机意外,管路流量、离心泵转速和流量/转速比值均稳定.ALT、总胆红素(TBIL)和谷氨酰转移酶(GGT)稳定,灌注开始至结束各时间点与术前相比,差异均无统计学意义(P均>0.05).灌注开始后AST缓慢上升,灌注第8、10和12小时AST分别为(73±21)、(90±30)和(114±48)(U/L),与术前相比,差异均有统计学意义(P均<0.05).在实验猪心脏停跳的5 min内,乳酸在灌注开始时便处于峰值,自灌注第8小时起,乳酸数值与峰值相比差异均有统计学意义(P均<0.05).K+浓度水平自灌注第2小时起各时间点与灌注开始时相比,差异均有统计学意义(P均<0.05).ALT、TBIL、GGT、血尿素氮、血清肌酐、血气分析指标、Na+、Ca2+和Cl-浓度水平稳定,灌注开始至结束各时间点数值与灌注开始时相比,差异均无统计学意义(P均>0.05).自灌注开始后持续有胆汁生成、尿量产生.供肝灌注12 h的过程中,肝脏始终保持外观红润、质地柔软、边缘锐利.灌注结束后,胆总管、肝、肾和小肠组织病理结果 示组织结构完整,无淤血和大面积坏死征象.结论 便携式IMPD可以稳定灌注无心跳猪供器官12 h,可以较好维护胆总管、肝、肾和小肠器官.

利用三元杂交猪作为实验模型猪,分析三元杂交猪在麻醉情况下常规生理血气生化指标测定.本实验选用20例30～40 kg健康的雌性三元杂交猪麻醉处理,用血气仪、血液生化仪进行猪血液的血气、生化检验,将三元杂交猪的14项血气指标、9项血液生化指标进行组间比较,分析三元猪在麻醉状态下血气及生化与其他小型猪血液相关数据的差异,结果显示三元杂交猪大部分血液生理血气生化指标均呈正态分布,其中PaO2、AST、GGT、TBIL、DBIL、IBIL为偏态分布,血气生化检测值与巴马猪及其他实验小型猪参考生理值存在较小差异.

随着众包系统的兴起,人们对众包系统的关注逐渐增多.基于众包系统中的任务推荐,研究者大多将用户对任务的行为数据转化为评分,但没有考虑任务关联关系以及用户兴趣变化对推荐结果的影响.为此,提出一种考虑任务关联度与时间因素的改进OCCF方法,以对任务进行推荐.一方面,在负例抽取阶段引入兴趣遗忘函数,并根据用户活跃度抽取一定数量的负例;另一方面,在概率矩阵分解阶段融合任务相似度信息以进行分解.将所提出的方法应用于众包系统的任务推荐中,利用威客任务中国的数据集进行了实验.实验结果表明,与主流方法相比,所提方法取得了更好的结果,能有效地提高推荐质量.

With the rapid development of information technology, scientific social network, i.e. SSN, have become the fastest and most convenient way for researchers to communicate with each other. However, a lot of published articles are shared via SSN every day which make it difficult for researchers to find highly valuable articles. To solve above information overload problem, a novel hybrid approach integrating with social information, i.e., HAR-SI, is proposed for the article recommendation in SSN. Unlike the traditional CBF and CF recommendation approaches, the social tag information and social friend information, which have been proved playing a significant role on recommendation in many domains, are effectively integrated into these two approaches separately to improve the accuracy in SSN. Prediction results made by the improved CBF and CF separately are combined with a hybrid method. In order to verify the effectiveness of the proposed HAR-SI, a real-life dataset from CiteULike was employed. Experimental results show that the proposed approach provides higher quality recommendations than the baseline methods, thus providing a more effective manner to recommend articles in SSN.

With the rapid development of information technology, scientific social networks (SSNs) have become the fastest and most convenient way for researchers to communicate with each other. Many published papers are shared via SSNs every day, resulting in the problem of information overload. How to appropriately recommend personalized and highly valuable papers for researchers is becoming more urgent. However, when recommending papers in SSNs, only a small amount of positive instances are available, leaving a vast amount of unlabelled data, in which negative instances and potential unseen positive instances are mixed together, which naturally belongs to One-Class Collaborative Filtering (OCCF) problem. Therefore, considering the extreme data imbalance and data sparsity of this OCCF problem, a hybrid approach of Social and Content aware One-class Recommendation of Papers in SSNs, termed SCORP, is proposed in this study. Unlike previous approaches recommended to address the OCCF problem, social information, which has been proved playing a significant role in performing recommendations in many domains, is applied in both the profiling of content-based filtering and the collaborative filtering to achieve superior recommendations. To verify the effectiveness of the proposed SCORP approach, a real-life data-set from CiteULike was employed. The experimental results demonstrate that the proposed approach is superior to all of the compared approaches, thus providing a more effective method for recommending papers in SSNs.

In this paper ,the improved one class collaborative filtering with social information (OCCF‐SI) is proposed .On the one hand ,the user’s activity and the similarity between projects are consid‐ered when extracting the negative cases ;on the other hand ,the social information of user’s friends relations and project’s labels is merged into the probability matrix factorization .The experiments on the real dataset in a scientific social network named CiteULike are conducted .The experimental re‐sults show that compared to other traditional recommendation methods ,the proposed method gets the best recommendation results and performs well in scalability .