Our aim was to analyze the short-and long-term function of kidneys procured from non-heartbeating donors (NHBD) by means of three techniques: in situ perfusion (ISP), total body cooling (TBC) and normothermic recirculation (NR). (52 Yo) showed delayed graft function (DGF) and 9 (16 %) showed primary non function (PNF). The actuarial graft survival rate was 76.4 Yo at 1 year and 56 YO at 5 years. The patient survival rate was 89.3 YO at 5 years. Incidence of DGF and PNF was significantly lower in kidneys perfused with NR than those with ISP or TBC ( P < 0.01). Duration of DGF was shorter in kidneys obtained through TBC than in kidneys obtained with ISP (P < 0.05).In conclusion, NR reduces the incidence of DGF and may be considered the method of choice for kidney procurement from NHBD.

Our aim was to analyze the short- and long-term function of kidneys procured from non- heartbeating donors (NHBD) by means of three techniques: in situ perfusion (ISP), total body cooling (TBC) and normothermic recirculation (NR). Fifty-seven potential NHBD were included. Mean warm ischemia time was 68.9 +/- 35.6 min. Forty-four kidneys were obtained from donors perfused with ISP, 8 with TBC, and 8 with NR. Eighteen kidneys (32%) started functioning immediately, 29 (52%) showed delayed graft function (DGF) and 9 (16%) showed primary non function (PNF). The actuarial graft survival rate was 76.4% at 1 year and 56% at 5 years. The patient survival rate was 89.3% at 5 years. Incidence of DGF and PNF was significantly lower in kidneys perfused with NR than those with ISP or TBC (P < 0.01). Duration of DGF was shorter in kidneys obtained through TBC than in kidneys obtained with ISP (P < 0.05). In conclusion, NR reduces the incidence of DGF and may be considered the method of choice for kidney procurement from NHBD.

No abstract

Human amniotic membrane (HAM) has useful properties as a dermal matrix substitute. The objective of our work was to obtain, using different enzymatic or chemical treatments to eliminate cells, a scaffold of acellular HAM for later use as a support for the development of a skin equivalent. The HAM was separated from the chorion, incubated and cryopreserved. The membrane underwent different enzymatic and chemical treatments to eliminate the cells. Fibroblasts and keratinocytes were separately obtained from skin biopsies of patients following a sequential double digestion with first collagenase and then trypsin-EDTA (T/E). A skin equivalent was then constructed by seeding keratinocytes on the epithelial side and fibroblasts on the chorionic side of the decellularizated HAM. Histological, immunohistochemical, inmunofluorescent and molecular biology studies were performed. Treatment with 1% T/E at 37 °C for 30 min totally removed epithelial and mesenchymal cells. The HAM thus treated proved to be a good matrix to support adherence of cells and allowed the achievement of an integral and intact scaffold for development of a skin equivalent, which could be useful as a skin substitute for clinical use.

Regenerative medicine, based on the use of stem cells, scaffolds and growth factors, has the potential to be a good approach for restoring damaged tissues of the central nervous system. This study investigated the use of human amniotic mesenchymal stem cells (hAMSC), human amniotic epithelial stem cells (hAESC), and human Wharton's jelly mesenchymal stem cells (hWJMSC) derived from human umbilical cord as a source of stem cells, and the potential of the human amniotic membrane (HAM) as a scaffold and/or source of growth factors to promote nerve regeneration. The hAMSC and hAESC obtained from HAM and the hWJMSC from umbilical cords were cultured in induction medium to obtain neural-like cells. The morphological differentiation of hAMSC, hAESC and hWJMSC into neural-like cells was evident after 4-5 days, when they acquired an elongated and multipolar shape, and at 21 days, when they expressed neural and glial markers. On other way, the HAM was completely decellularized without affecting the components of the basement membrane or the matrix. Subsequently, hAMSC, hAESC and hWJMSC differentiated into neural-like cells were seeded onto the decellularized HAM, maintaining their morphology. Finally, conditioned media from the HAM allowed proliferation of hAMSC, hAESC and hWJMSC differentiated to neural-like cells. Both HAM and umbilical cord are biomaterials with great potential for use in regenerative medicine for the treatment of neurodegenerative diseases.

A 'Critical pathway for deceased tissue donation' was developed by the European Committee on Organ Transplantation of the Council of Europe (CD-P-TO) with the aim of providing a common systematic approach to the deceased tissue donation process. Definitions of tissue donors according to the donation stage have been developed so that they can be adapted to different local scenarios. This critical pathway can be used retrospectively to evaluate the potential of tissue donation, assess performance in the tissue donation process and identify areas for improvement. It sets the basis to build indicators to compare organizations, regions and countries. The critical pathway can also be used prospectively to promote good practices in tissue donation programmes aimed at covering the tissue transplantation needs of patients.

The purpose of the current study was to establish a valid protocol for nerve cryopreservation, and to evaluate if the addition of albumin supposed any advantage in the procedure. We compared a traditional cryopreservation method that uses dimethyl sulfoxide (DMSO) as cryoprotectant, to an alternative method that uses DMSO and albumin. Six Wistar Lewis rats were used to obtain twelve 20 mm fragments of sciatic nerve. In the first group, six fragments were cryopreserved in 199 media with 10% DMSO, with a temperature decreasing rate of 1 °C per minute. In the second group, six fragments were cryopreserved adding 4% human albumin. The unfreezing process consisted of sequential washings with saline in the first group, and saline and 20% albumin in the second group at 37 °C until the crioprotectant was removed. Structural evaluation was performed through histological analysis and electronic microscopy. The viability was assessed with the calcein-AM (CAM) and 4',6-diamino-2-fenilindol (DAPI) staining. Histological results showed a correct preservation of peripheral nerve architecture and no significant differences were found between the two groups. However, Schwann cells viability showed in the CAM-DAPI staining was significantly superior in the albumin group. The viability of Schwann cells was significantly increased when albumin was added to the nerve cryopreservation protocol. However, no significant structural differences were found between groups. Further studies need to be performed to assess the cryopreserved nerve functionality using this new method.

<b><i>Background:</i></b> Although transmission of pathogenic viruses through human tissue grafts is rare, it is still one of the most serious dreaded risks of transplantation. Therefore, in addition to the detailed medical and social history, a comprehensive serologic and molecular screening of the tissue donors for relevant viral markers for human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) is necessary. In the case of reactive results in particular, clear decisions regarding follow-up testing and the criteria for tissue release must be made. <b><i>Methods:</i></b> Based on the clinical relevance of the specific virus markers, the sensitivity of the serological and molecular biological methods used and the application of inactivation methods, algorithms for tissue release are suggested. <b><i>Results:</i></b> Compliance with the preanalytical requirements and assessment of a possible hemodilution are mandatory requirements before testing the blood samples. While HIV testing follows defined algorithms, the procedures for HBV and HCV diagnostics are under discussion. Screening and decisions for HBV are often not as simple, e.g., due to cases of occult HBV infection, false-positive anti-HBc results, or early window period positive HBV NAT results. In the case of HCV diagnostics, modern therapies with direct-acting antivirals, which are often associated with successful treatment of the infection, should be included in the decision. <b><i>Conclusion:</i></b> In HBV and HCV testing, a high-sensitivity virus genome test should play a central role in diagnostics, especially in the case of equivocal serology, and it should be the basis for the decision to release the tissue. The proposed test algorithms and decisions are also based on current European recommendations and standards for safety and quality assurance in tissue and cell banking.