How to apply ex-vivo split liver transplantation safely and feasibly: A three-step approach

BACKGROUND Given the current organ shortage crisis,split liver transplantation(SLT)has emerged as a promising alternative for select end-stage liver disease patients.AIM To introduce an ex-vivo liver graft splitting approach and evaluate its safety and feasibility in SLT.METHODS A retrospective analysis was conducted on the liver transplantation data from cases performed at our center between April 1,2022,and May 31,2023.The study included 25 SLT cases and 81 whole liver transplantation(WLT)cases.Total ex-vivo liver splitting was employed for SLT graft procurement in three steps.Patient outcomes were determined,including liver function parameters,postoperative complications,and perioperative mortality.Group comparisons for categorical variables were performed using theχ²-test.RESULTS In the study,postoperative complications in the 25 SLT cases included hepatic artery thrombosis(n=1)and pulmonary infections(n=3),with no perioperative mortality.In contrast,among the 81 patients who underwent WLT,complications included perioperative mortality(n=1),postoperative pulmonary infections(n=8),abdominal infection(n=1),hepatic artery thromboses(n=3),portal vein thrombosis(n=1),and intra-abdominal bleeding(n=5).Comparative analysis demonstrated significant differences in alanine aminotransferase(176.0 vs 73.5,P=0.000)and aspartate aminotransferase(AST)(42.0 vs 29.0,P=0.004)at 1 wk postoperatively,and in total bilirubin(11.8 vs 20.8,P=0.003)and AST(41.5 vs 26.0,P=0.014)at 2 wk postoperatively.However,the overall incidence of complications was comparable between the two groups(P>0.05).CONCLUSION Our findings suggest that the total ex-vivo liver graft splitting technique is a safe and feasible approach,especially under the expertise of an experienced transplant center.The approach developed by our center can serve as a valuable reference for other transplantation centers.

A new veno-venous bypass type for ex-vivo liver resection in dogs

Ex-vivo liver resection is a procedure in which the liver is completely removed, perfused and after bench surgery, the liver is autotransplanted to the original site. Ex vivo liver resection is an important treatment for unresectable liver tumors. This surgical procedure requires long operation time, during which blood flow must be carefully maintained to avoid venous congestion. An effective veno-venous bypass (VVB) may meet this requirement. The present study was to test our new designed VVB device which comprised one heparinized polyvinylchloride tube and three magnetic rings The efficacy of this device was tested in five dogs. A VVB was established in 6-10 minutes. There was no leakage during the procedure. Hemodynamics was stable at anhepatic phase, which indicated that the bypass was successful. This newly-developed VVB device maintained circulation stability during ex-vivo liver resection in our dog model and thus, this VVB device significantly shortened the operation time.

Accuracy of combined PET/CT in image-guided interventions of liver lesions: An ex-vivo study

AIM： Positioning of interventional devices in liver lesions is a challenging task if only CT is available. We investigated the potential benefit of combined PET/CT images for localization of interventional devices in interventional liver studies. METHODS： Thirty lesions each of hyperdense, isodense and hypodense attenuation compared to normal liver parenchyma were injected into 15 ex-vivo pig livers. All lesions were composed of the same amounts of gelatine containing 0.5 MBq of ^18F-FDG. Following lesion insertion, an interventional needle was placed in each lesion under CT-guidance solely. After that, a PET/CT study was performed. The localization of the needle within the lesion was assessed for CT alone and PET/CT and the root mean square （RMS） was calculated. Results were compared with macroscopic measurements after lesion dissection serving as the standard of reference. RESULTS： In hypo- and isodense lesions PET/CT proved more accurate in defining the position of the interventional device when compared with CT alone. The mean RMS for CT and PET/CT differed significantly in isodense and hypodense lesions. No significant difference was found for hyperdense lesions. CONCLUSION： Combined FDG-PET/CT imaging provides more accurate information than CT alone concerning the needle position in FDG-PET positive liver lesions. Therefore combined PET/CT might be potentially beneficial not only for localization of an interventional device, but may also be beneficial for guidance in interventional liver procedures.

Using computed tomography scans to develop an ex-vivo gastric model

The objective of this research was to use abdominal computed tomography (CT) scans to non-invasively quantify anthropometrical data of the human stomach and to concomitantly create an anatomically correct and distensible ex-vivo gastric model. Thirty-three abdominal CT scans of human subjects were obtained and were imported into reconstruction software to generate 3D models of the stomachs. Anthropometrical data such as gastric wall thickness, gastric surface area and gastric volume were subsequently quantified. A representative 3D computer model was exported into a selective laser sintering (SLS) rapid prototyping machine to create an anatomically correct solid gastric model. Subsequently, a replica wax template of the SLS model was created. A negative mould was offset around the wax template such that the offset distance was equivalent to that of the gastric wall thickness. A silicone with similar mechanical properties to the human stomach was poured into the offset. The lost wax manufacturing technique was employed to create a hollow distensible stomach model. 3D computer gastric models were generated from the CT scans. A hollow distensible silicone ex-vivo gastric model with similar compliance to that of the human stomach was created. The anthropometrical data indicated that there is no significant relationship between BMI and gastric surface area or gastric volume. There were inter- and intra-group differences between groups with respect to gastric wall thickness. This study demonstrates that abdominal CT scans can be used to both non-invasively determine gastric anthropometrical data as well as create realistic ex-vivo stomach models.

Mechanical circulatory support in lung transplantation: Cardiopulmonary bypass, extracorporeal life support, and ex-vivo lung perfusion

Lung transplant is the standard of care for patients with end-stage lung disease refractory to medical management. There is currently a critical organ shortage for lung transplantation with only 17% of offered organs being transplanted. Of those patients receiving a lung transplant, up to 25% will develop primary graft dysfunction, which is associated with an 8-fold increase in 30-d mortality. There are numerous mechanical lung assistance modalities that may be employed to help combat these challenges. We will discuss the use of mechanical lung assistance during lung transplantation, as a bridge to transplant, as a treatment for primary graft dysfunction, and finally as a means to remodel and evaluate organs deemed unsuitable for transplant, thus increasing the donor pool, improving survival to transplant, and improving overall patient survival.

Micro-Computed Tomography Applications in Dentistry

Micro-computed tomography (MCT) encompasses two primary scanning options: ex-vivo and in-vivo imaging. Ex-vivo scanning involves the examination of extracted teeth or dental specimens, allowing for detailed analyses of the microarchitecture of mineralized tissue. By analyzing the microarchitecture of dental tissues, MCT can provide valuable information about bone density, porosity, and microstructural changes, contributing to a better understanding of disease progression and treatment outcomes. Moreover, MCT facilitates the quantification of dental parameters, such as bone volume, trabecular thickness, and connectivity density, which are crucial for evaluating the efficacy of dental interventions. This present study aims to comprehensively review and explore the applications of MCT in dentistry and highlight its potential in advancing research and clinical practice. The results depicted that the quantitative approach of MCT enhances the precision and reliability of dental research. Researchers and clinicians can make evidence-based decisions regarding treatment strategies and patient management, relying on quantifiable data provided by MCT. The applications of MCT in dentistry extend beyond research, with potential clinical implications in fields such as dental implantology and endodontics. MCT is expected to play an increasingly significant role in enhancing our understanding of dental pathologies, improving treatment outcomes, and ultimately, benefiting patient care in the field of dentistry.

终末期肝泡型包虫病的肝移植治疗

肝泡型包虫病(HAE)是我国西部地区常见的人畜共患地方性寄生虫病,早期缺乏典型临床表现,症状明显时常已进入终末期,具有极高的致死率。在终末期HAE(es-HAE)治疗中,因残余肝体积不足、无法控制的出血、脉管在体重建困难等,同种异体原位肝移植几乎成为唯一根治的方式。但因供肝短缺、术后需长期使用免疫抑制药等因素限制了其应用,离体肝切除联合自体肝移植术(ELRA)的出现打破了这一窘境,极大拓宽了es-HAE手术指征。此外,我国多中心对ELRA进行了诸多优化与改良,进一步完善es-HAE的治疗体系。目前,es-HAE的肝移植(包括ELRA)治疗仍是临床医师研究的热点。本文对原位肝移植、ELRA、辅助性ELRA等多种手段在es-HAE的外科治疗进行综述,旨在进一步提升es-HAE的诊治水平,改善患者临床预后。

1470 nm半导体激光对离体动物组织的汽化消融、切割和凝固作用

目的观察1470 nm波长的半导体激光对离体动物组织的汽化切割、凝固和热损伤情况,以探讨其应用于前列腺增生治疗的可行性。方法实验组和同类对照组分别使用HANS-D1型和ML-DD01FI型1470 nm半导体激光治疗仪。取新鲜离体猪膀胱组织,光纤距离组织0.5 cm和1 cm的条件下工作5 s,观察60、90、120、150、160 W功率的半导体激光对组织的损伤影响;取离体犬前列腺和猪肾组织分别进行汽化消融和汽化切割,观察60、90、120、150、160 W功率的半导体激光对组织的汽化和热损伤作用;另在凝结模式下照射离体猪肾组织5、10、15 s后,观察30、40、50 W功率的半导体激光对组织的凝固作用。结果光纤照射距离组织1 cm时,1470 nm半导体激光对邻近正常膀胱组织不会产生意外损伤;但在距离0.5 cm时,120、150、160 W的1470 nm半导体激光对膀胱组织有轻微的损伤。另外,随着输出功率的增大,60~160 W半导体激光对犬前列腺组织的汽化消融效率逐渐提高,且汽化量和消耗总能量之间呈良好的线性相关(P<0.001)。病理组织学HE染色结果显示实验组的凝固层厚度为292.20~309.98μm,汽化层深度为1.49~4.52 mm;同类对照组的凝固层厚度为289.91~303.53μm,汽化层深度为1.88~4.43 mm,两组间比较均未见明显差异(P>0.05)。同时,汽化切割截面积为1 cm2的离体猪肾组织时,60~160 W的1470 nm半导体激光对肾组织的汽化切割效率随输出功率的增大而提高(P<0.05),其中实验组的凝固层厚度为496.04~514.47μm,同类对照组的凝固层厚度为489.39~518.53μm。此外,凝结模式下30、40、50 W的半导体激光对离体猪肾组织照射5、10、15 s时,随着激光输出功率的增加,凝固瘢直径、凹槽深度和凝固效率均逐渐增大(P<0.05);其中实验组和同类对照组的凝固层厚度分别为399.10~449.98μm和392.97~447.65μm,汽化层深度分别为3.05~7.09 mm和2.70~7.14 mm,两组间比较均未见明显差异(P>0.05)。结论1470 nm半导体激光对离体动物组织具有良好的汽化消融、切割和凝固作用,其效果与输出能量之间具有良好的线性相关。

高尿酸环境对晶状体透明度的影响及作用机制

目的通过构建大鼠晶状体离体培养模型探讨高尿酸环境对白内障形成的影响及机制。方法采用成年Sprague Dawley大鼠晶状体,在高尿酸培养环境下离体培养。将大鼠晶状体分为空白对照组(15眼)和尿酸干预组(15眼)。尿酸干预组采用含尿酸800μmol·L-1的M-199培养液培养,空白对照组采用不含尿酸的M-199培养液培养,均培养7 d。通过光学显微镜观察两组大鼠晶状体混浊程度;Gomori六胺银法检测两组大鼠晶状体中尿酸盐沉积情况;SA-β-gal染色法检测两组大鼠晶状体细胞衰老情况;TUNEL染色法检测两组大鼠晶状体细胞凋亡情况。结果尿酸干预组大鼠晶状体于第5天时开始出现混浊,并于第7天时混浊分级显著升高,与空白对照组大鼠晶状体混浊分级相比,差异均有统计学意义(均为P<0.05)。空白对照组大鼠晶状体上皮细胞排列整齐,周围未见尿酸盐沉积,仅有极少数蓝染的晶状体上皮细胞,且未发现明显的阳性细胞;尿酸干预组大鼠晶状体赤道部及前囊下晶状体上皮细胞排列紊乱,周围出现黑棕色的尿酸盐结晶,出现较多的蓝染晶状体上皮细胞,且出现了少量阳性细胞。高尿酸环境下,尿酸盐结晶在大鼠晶状体囊膜下沉积,周围晶状体上皮细胞衰老,少量晶状体上皮细胞凋亡。结论高尿酸环境在大鼠晶状体离体培养模型中能够稳定有效地诱导白内障的发生,其机制可能与尿酸诱导晶状体上皮细胞发生衰老和凋亡有关。

化妆品防腐剂苯氧乙醇和对羟基苯甲酸丙酯的皮肤安全性和暴露量

应用多种试验方法评估苯氧乙醇和对羟基苯甲酸丙酯的皮肤安全性和在皮肤中暴露量。所用的试验方法包括鸡胚绒毛尿囊膜(CAM)、斑马鱼胚模型、细胞中基质金属蛋白酶2(MMP-2)抑制测定法和离体猪皮渗透试验。鸡胚试验显示二者在0.2%质量分数时不会对眼产生刺激性;斑马鱼胚模型表明,2个防腐剂质量分数在0.01%不会对斑马鱼胚摆尾产生显著影响;2个防腐剂质量分数分别为0.1%和0.01%不会对MMP-2产生显著抑制;离体猪皮渗透试验显示对羟基苯甲酸丙酯经皮累积透过量仅是苯氧乙醇累积透过量的5%,但其在皮肤角质层和真皮层中驻留量均较大,在20 min贴敷时约是苯氧乙醇驻留量的2.5和5.8倍。可为化妆品中防腐剂安全使用提供一种评估方法。

人类体外胚胎利用活动的私法回应——以《民法典》第一千零九条为中心

面对人类体外胚胎利用活动,《民法典》不仅选择积极介入而且决定有限开放。为避免潜在风险,《民法典》不仅直接规定了多种风险预防机制,如提高合法标准、设置三大底线和强调人格尊严,而且还间接引致了多种风险预防机制,如划定行为禁区、限制利用对象和实施伦理审查。即便是在《民法典》的框架下,对人类体外胚胎的利用活动所引发的损害进行救济依然是可能的。但是,《民法典》所能供给的侵权责任方案存在很多局限。因此,后续立法应同时引入其他损害救济方案。从我国现行立法来看,潜在选择有强制责任保险方案、商业保险方案、社会救助基金方案和国家补偿方案。后续立法甚至可以建立同时包含四者的综合救济体系。为确保受害人能获得救济,应由国家兜底。

Normothermic Ex-vivo Liver Perfusion and the Clinical Implications for Liver Transplantation

Despite significant improvements in outcomes after liver trans-plantation,many patients continue to die on the waiting list,while awaiting an available organ for transplantation.Organ shortage is not only due to an inadequate number of available organs,but also the inability to adequately assess and evaluate these organs prior to transplantation.Over the last few decades,ex-vivo perfusion of the liver has emerged as a useful technique for both improved organ preservation and assessment of organs prior to transplantation.Large animal studies have shown the superiority of ex-vivo perfusion over cold static storage.However,these studies have not,necessa-rily,been translatable to human livers.Small animal studies have been essential in understanding and improving this tech-nology.Similarly,these results have yet to be translated into clinical use.A few Phase 1 clinical trials have shown promise and confirmed the viability of this technology.However,more robust studies are needed before ex-vivo liver perfusion can be widely accepted as the new clinical standard of organ preser-vation.Here,we aimed to review al relevant large and smal animal research,as well as human liver studies on normother-mic ex-vivo perfusion,and to identify areas of deficiency and opportunities for future research endeavors.

Review of ex-vivo characterisation of corneal biomechanics

The evaluation of the corneal biomechanical behaviour has important clinical applications.To name a few,the accuracy of the intraocular pressure measurement,the study of corneal ectatic diseases and the assessment and optimisation of corneal surgical procedures are all highly influenced by corneal biomechanics.Over the last 45 years different ex-vivo methods were developed to study corneal biomechanical behaviour.Different tissue maintenance,support,loading systems,as well as different monitoring strategies of corneal deformations were employed.In this review,the most important and commonly used methods are outlined,including strip extensiometry,inflation,compression,indentation and tissue separation testing.Their particularities,applications,pros and cons and main applications are discussed.

外科住院医师利用动物离体器官训练手术技能的方法与效果观察

目的探索外科住院医师利用动物离体器官进行手术技能训练的方法与效果。方法选取2020年11月至2021年3月期间13家培训基地参加外科住院医师规范化培训(简称住培)的372名外科住院医师,分为观察组和对照组。观察组接受动物离体器官训练系统培训并进行考核,其中,参加开腹阑尾切除术96人次,参加腹腔镜阑尾切除术132人次,参加腹腔镜肾囊肿去顶减压术71人次。对照组接受传统外科带教模式培训后进行考核,接受开腹阑尾切除术考核16人次、腹腔镜阑尾切除术考核26人次、腹腔镜肾囊肿去顶减压术考核29人次。结果观察组三种术式培训后成绩均明显高于培训前成绩(均P<0.05);培训后观察组三种术式成绩均明显高于对照组(均P<0.05)。各培训基地之间培训前三种术式成绩差异显著(P<0.05);培训后各培训基地开腹阑尾切除术、腹腔镜阑尾切除术的考核成绩无显著差异(P>0.05)。结论动物离体器官手术训练可以有效提高外科住院医师开腹阑尾切除术、腹腔镜阑尾切除术、腹腔镜肾囊肿去顶减压术三种术式的外科手术技能,可促进开腹阑尾切除术、腹腔镜阑尾切除术的培训均质化。

450 nm半导体蓝激光对肾盂组织汽化切割效应的离体动物实验研究

目的 探究450 nm半导体蓝激光在不同作用距离、功率下汽化切割肾盂组织后的形态和热损伤范围。方法 将新鲜离体猪肾盂纵行剖开,切成约7 cm×5 cm×3 cm的方块。激光光纤固定在垂直于肾盂组织的机械臂上,光纤头与肾盂组织距离1~2 mm,以1~2 mm/s的恒定速度对肾盂组织进行切割,蓝激光功率5~30 W,再将切割后的肾盂组织固定于福尔马林中,采用肉眼及显微镜评估其形态、汽化深度、宽度及凝固厚度。结果 使用不同功率汽化肾盂组织时汽化效果不同,作用距离为2 mm、速度为2 mm/s,当激光功率为5 W时,汽化深度约0.9 mm,汽化宽度约0.25 mm,凝固层厚度约0.35 mm。随着功率的增加汽化宽度和深度随之增加,而凝固层范围即热损伤厚度介于0.35~0.50 mm;当功率大于10 W时,肾盂肌层组织易被穿透;当激光功率为20 W时,肾盂组织被汽化后组织切面呈现不规则的汽化效果。当激光作用距离为1 mm时,肾盂肌层组织容易被全层汽化;而激光汽化距离为2 mm、速度为2 mm/s时产生了较安全的能量治疗窗口。结论 450 nm半导体蓝激光可对肾盂组织进行安全有效的汽化切割,精准度高且热损伤小,有望用于临床成为治疗肾盂内病变的新的手术工具。

肝素涂层插管生物相容性评价

对肝素涂层插管和未涂层插管设计了抗凝血、血栓形成观察以及溶血、细胞毒性、炎性和免疫反应等多种试验,从多角度综合对肝素涂层插管材料进行生物相容性评价。通过活化部分凝血活酶时间(APTT)、凝血酶原时间(PT)、纤维蛋白原降解产物(FIB)、凝血酶时间(TT)、血小板活化因子、纤维蛋白吸附等试验,测定样品的体外抗凝血性,然后通过半体内血栓形成试验,模拟插管在动物体内的使用环境和过程,观察样品引起血栓形成的状况。同时,通过溶血试验和细胞毒性试验以及炎症反应、补体激活、免疫球蛋白等检测,进一步对样品进行血液相容性评价。结果显示,肝素涂层实验组APTT和TT得到有效延长,而其他体外抗凝指标未见显著变化;在动物半体内模型试验和检测中,肝素涂层实验组6 h血栓形成的各项指标均低于未涂层对照组,表明肝素涂层通过抑制内源性凝血途径达到了预期的抗凝效果;而溶血率、细胞毒性、炎症反应、补体激活、免疫球蛋白等方面的试验结果与未涂层对照组无差异,表明肝素涂层对材料的血液相容性无不良影响。结果表明,肝素涂层显著提高了动静脉插管的体内外抗凝血性,具有良好的生物相容性,可提高临床应用的安全性。

葡萄资源叶片抗炭疽病鉴定及抗病基因的QTL定位

【目的】炭疽病是葡萄的主要病害之一,极易造成大规模的病害流行,严重影响葡萄产量及品质,筛选抗病种质及挖掘抗病基因有利于葡萄抗病机制研究及抗病育种的开展。【方法】利用室内离体叶片接种法,对60份中国野生葡萄种质、122份欧亚种质、76份欧美杂种以及美人指×刺葡萄0940的F1代杂交群体进行炭疽病抗性鉴定与评价,并利用SNP标记构建的遗传图谱对炭疽病抗性进行QTL定位。【结果】经抗性鉴定,共筛选出1份高抗、43份抗病和75份中抗种质,分别占总鉴定种质的0.39%、16.67%和29.07%。以筛选出的抗病种质刺葡萄0940和感病种质美人指的杂交后代为分离群体进行QTL定位,在第8号连锁群上检测到一个与抗炭疽病相关的QTL位点,可解释14.7%的表型变异。根据QTL定位区间基因注释结果,筛选出15个抗病相关基因,推测它们在葡萄抗炭疽病中发挥一定作用。【结论】明确了不同葡萄种质的炭疽病抗性水平,定位到1个抗炭疽病QTL位点并筛选出15个抗病相关基因。

移植供肺的保存与功能维护

肺移植作为终末期肺病最后的治疗手段,不仅可以明显延长患者的生存时间,还能很大程度改善患者的生活质量。在过去的几十年里,随着外科技术、免疫抑制药和移植术后管理方面的进步,全球肺移植手术量激增。但供肺短缺极大限制了肺移植的发展,需要开发创新方法来扩大供者库。捐献者数量以及潜在供肺的有效保存与功能维护是扩大供者库的关键,供肺质量是保证肺移植受者术后长期生存的重要前提,移植肺的保存与功能维护在保证供肺质量方面尤为重要。本文总结了获取前供肺的管理与维护、供肺获取及移植肺的保存与功能维护的最新进展,以期为临床肺移植的发展提供参考。

氢分子及其制品对肺移植保护作用的研究进展

肺移植术后缺血-再灌注损伤是导致原发性移植物功能障碍的主要原因,进而会降低肺移植受者的移植肺功能和总体生存率。氢分子作为一种生理调节性分子,具有抗炎、改善氧化应激、减轻直接细胞损伤和缓解上皮细胞水肿等作用。近年来,越来越多的研究证明氢分子及其制品(主要是氢气和富氢溶液)可以显著改善肺移植术后缺血-再灌注损伤等并发症。本文就氢分子及其制品在肺移植中的保护作用及具体机制进行回顾总结,旨在为氢分子及其制品作为一种新的肺移植相关并发症治疗手段提供理论依据,进而改善肺移植受者的总体预后及生活质量。

美洲大蠊粪便提取物对大鼠离体心脏功能的影响研究

[目的]探究美洲大蠊粪便提取物(PAF)对大鼠离体心脏功能的影响。[方法]采用Langendorff灌流装置构建SD大鼠离体心脏灌流模型,检测各组左室收缩压(LVSP)、左心室压力最大上升和下降速率(±dp/dtmax)、心率(HR)等血流动力学指标的变化。[结果] PAF可显著提升正常大鼠离体心脏的LVSP和±dp/dtmax,且呈剂量依赖性,其中0.5 mg/mL的高剂量作用效果最为显著,但PAF对HR并未表现出明显的影响。[结论] PAF升高LVSP,增大±dp/dtmax,对大鼠离体心脏有正性肌力作用,能够增强心肌收缩力。PAF对心率未表现出明显影响,有利于降低心脏耗氧量,可能是其能够发挥心脏保护作用的重要原因。