Liver transplantation in a patient after COVID-19 – Rapid loss of antibodies and prolonged viral RNA shedding

To date, little is known about the duration and effectiveness of immunity as well as possible adverse late effects after an infection with SARS-CoV-2. Thus it is unclear, when and if liver transplantation can be safely offered to patients who suffered from COVID-19. Here, we report on a successful liver transplantation shortly after convalescence from COVID-19 with subsequent partial seroreversion as well as recurrence and prolonged shedding of viral RNA.     

The use of third-party packed red blood cells during ex situ normothermic machine perfusion of organs for transplantation: Underappreciated complexities?

Ex situ normothermic machine perfusion (NMP) is being used increasingly in the assessment of higher risk deceased donor organs and to facilitate prolonged organ storage. Third-party packed red blood cells (pRBCs) are often used as an oxygen carrier in the perfusate of ex situ NMP. Despite the increasing interest in NMP, comparatively little attention has been paid to the appropriate selection of pRBCs. This includes the choice of ABO blood group and Rhesus D status, the need for special requirements for selected recipients, and the necessity for traceability of blood components. Flushing organs with cold preservation solution after NMP removes the overwhelming majority of third-party allogeneic pRBCs, but residual pRBCs within the organ may have biologically relevant effects following implantation as they enter the recipient's circulation. This review considers these issues, and suggests that national transplant and blood transfusion agencies work together to develop a co-ordinated approach within each country. This is especially important given the possibility of organ re-allocation between centers after ex situ NMP, and the ongoing development of organ perfusion hubs.     

积分加权法评价磷化学烧伤实验病理的意义与应用

目的：积分加权法在病理组织学检查中的应用，方法：在常规病理描述基础上，采用积分加权法将病理结果予以定量，综合评价致伤后实验动物的主要脏器，结果：实验动物同等面积的磷酸烧伤各脏器积分降低，钙治疗后则显著改善，均与其它方面报道的资料一致，结论：积分加以数值使各脏器损伤程度一目了然，对不同脏器间的损伤情况有可比性，从而有助于了解主要受损脏器与总体的关系以及药物的治疗效果。     

Morphological, physiological and biochemical observations on skate electric organ

Summary The electric organs of two species of skate have been examined morphologically, physiologically and biochemically. They can be easily dissociated into innervated or denervated component electrocytes by a Torpedo Ringer's solution containing 1% collagenase. Collagenase treatment did not, however, separate the Schwann cell cover capping the synaptosomes. Isolated electrocytes generate normal MEPP frequencies and show evoked responses for two days in Torpedo Ringer's. The nerve terminals retain excitability and transmitter release properties up to the time of separation. Since isolated terminals and denervated electrocytes show normal ultrastructural characteristics for up to 12 h, the skate electric organ provides several preparations which are not attainable with Torpedo tissue. Acetylcholine (ACh) content of supernatant fractions containing the synaptosomes was comparable to that found in Torpedo (sps.). Collagenase specifically eliminates the basal lamina associated with the synaptic junctional region. Neuronal cell death and synaptic terminal degeneration were also noted in the adult organs of both species. The skate electric organ is ideally suited for the study of cholinergic development and transmission.     

兔中性粒细胞防御素对HL—60细胞毒性及对病毒的直接灭活作用

本研究从新西兰家兔腹腔渗出中性粒细胞溶酶体内提取酸溶性组分，经制备性ＡＵ－ＰＡＧＥ获得纯化的防御素（ＮＰ１和ＮＰ２），ＳＤＳ－ＰＡＧＥ测定分子量为３ｋｄ左右。以ＨＬ－６０细胞作靶细胞，当ＮＰ１或ＮＰ２在１００μｇ／ｍｌ浓度时，可杀死６０％以上的ＨＬ－６０细胞。ＮＰ１（２６０μｇ／ｍｌ）还可直接灭活单纯疱疹病毒Ｉ型和乙型流感病毒，分别使病毒感染滴度降度９８．２％和９０％。本研究结果提示，中性粒细胞可     

氯丙嗪预处理对冷保存肝脏缺血性损伤的影响

目的：本实验旨在探讨利用氯丙嗪预处理供体,观察对冷保存过程中供体肝脏缺血性损伤的保护作用及其作用机制。方法：切取大鼠肝脏在0℃Euro-Collins液中冷保存,每隔2小时切取肝脏标本测定GSH,ATP含量。结果：实验结果表明,随着肝脏冷保存时间的延长,对照组肝组织内的GSH及ATP含量迅速下降。实验组肝组织内的GSH和ATP含量下降速度明显缓慢。结论：本文认为,氯丙嗪预处理供体有改善肝组织在冷保存过程中的缺血性损伤作用。其主要作用机制可能是由于氯丙嗪作为Ca^ 通道的阻滞剂,降低肝细胞胞浆内Ca^ 浓度,减少ATP的消耗和氧自由基的生成,维持肝组织内GSH和ATP的含量,从而减轻了肝脏在冷保存过程中的缺血性损伤。