Corneal cryopreservation can partially solve the worldwide concern regarding donor cornea shortage for keratoplasties. In this study, human corneas were cryopreserved using two standard ...cryopreservation protocols that are employed in the Tissue Bank of the Teresa Herrera Hospital (Spain) to store corneas for tectonic keratoplasties (TK protocol) and aortic valves (AV protocol), and two vitrification protocols, VS55 and DP6. Endothelial viability and general corneal state were evaluated to determine the protocol that provides the best results. The potential corneal cryopreservation protocol was studied in detail taking into consideration some cryopreservation-related variables and the endothelial integrity and stroma arrangement of the resulting cryopreserved corneas. TK corneas showed mostly viable endothelial cells, while the others showed few (AV) or none (DP6 and VS55). The corneal structure was well maintained in TK and AV corneas. TK corneas showed endothelial acellular areas surrounded by injured cells and a normal-like stromal fiber arrangement. Cryoprotectant solutions of the TK protocol presented an increasing osmolality and a physiological pH value. Cooling temperature rate of TK protocol was of 1 °C/min to -40 °C and 3 °C/min to -120 °C, and almost all of dimethyl sulfoxide left the tissue after washing. Future studies should be done changing cryopreservation-related variables of the TK protocol to store corneas of optical grade.
In view of the public consultation recently launched by the World Health Organization on Regulatory Convergence of Cell and Gene Therapy Products and the Proposal for a Regulation on substances of ...human origin (SoHO) repealing the European Union Directives on Blood and on Tissues and Cells, an opportunity arises to define an ethical and transparent framework of collaboration between industry and authorities responsible for SoHO-derived products, comprising medicines, medical devices, transfusion, and transplantation. The commodification of SoHO-derived medicinal products and medical devices entails important risks to the sustainability of healthcare systems and threatens the equitable access of patients to innovative therapies. It may also jeopardize the principle of altruistic donation of SoHO that is required for the treatment and survival of thousands of patients every year. This article puts forward several proposals aimed at reconciling the ethical principles of voluntary and unpaid SoHO donation and the noncommercialization of the human body with obtaining a profit that allows business activities, while ensuring high quality, safety, and efficacy standards of tissues and cells for clinical use.
Physical examination (PE) of donors is essential to identify potential risks to the safety and efficacy of donated organs and tissues and is mandatory in the EU. However, no detailed guidance is ...available as to how PE should be performed. Health authorities (HA) and health professionals (HP) in member states of the European Committee on Organ Transplantation of the Council of Europe (CD-P-TO) and observer countries completed surveys relating to the regulatory requirements for PE and the professional practice of PE in their countries for organ and tissue donors. The HA survey addressed regulatory aspects, and the HP survey addressed professional practices, training, and respondents' opinions on the value of PE. These surveys revealed significant inter-country variation in the regulatory approach to PE and the performance of PE by professionals. Most respondents opined that PE was important and yielded valuable information in identifying contraindications to donation. There is no consensus at a regulatory or professional level as to how PE should be performed on organ and tissue donors. There is a requirement for agreed best practice guidelines in this area.
Organ, tissue, and cell donation and transplantation legislation and policies vary substantially worldwide, as do performance outcomes in various jurisdictions. Our objective was to create expert, ...consensus guidance that links evidence and ethical concepts to legislative and policy reform for tissue and cell donation and transplantation systems.
We identified topic areas and recommendations through consensus, using nominal group technique. The proposed framework was informed by narrative literature reviews and vetted by the project's scientific committee. The framework was presented publicly at a hybrid virtual and in-person meeting in October 2021 in Montréal, Canada, where feedback provided by the broader Forum participants was incorporated into the final manuscript.
This report has 13 recommendations regarding critical aspects affecting the donation and use of human tissues and cells that need to be addressed internationally to protect donors and recipients. They address measures to foster self-sufficiency, ensure the respect of robust ethical principles, guarantee the quality and safety of tissues and cells for human use, and encourage the development of safe and effective innovative therapeutic options in not-for-profit settings.
The implementation of these recommendations, in total or in part, by legislators and governments would benefit tissue transplantation programs by ensuring access to safe, effective, and ethical tissue- and cell-based therapies for all patients in need.
To assess to which extent the COVID-19 pandemic affected corneal transplantation by virtue of donor selection algorithms in different European countries.
Survey.
110 eye banks in 26 European ...countries.
64 eye banks covering 95% of European corneal transplantation activity.
A questionnaire listing the number of corneas procured and distributed from February to May 2018-2020 was circulated to eye banks.
The primary outcome was the number of corneal procurements. Additional outcomes were national algorithms for donor selection, classified according to their stringency (donors with COVID-19 history, suspected for COVID-19, asymptomatic, PCR testing) and the pandemic severity in each country. We calculated Spearman's correlation coefficient to determine, two by two, the relationship between the 3-month decline in eye banking activity (procurement), the stringency of donor selection algorithm and the grading of pandemic severity (cases and deaths). A partial correlation was run to determine the relationship between decline and stringency while controlling for pandemic severity.
Procurements decreased by 38%, 68% and 41%, respectively, in March, April and May 2020 compared with the mean of the previous 2 years, while grafts decreased, respectively, by 28%, 68% and 56% corresponding to 3866 untreated patients in 3 months. Significant disparities between countries and the decrease in activity correlated with stringency in donor selection independent of pandemic severity.
Our data demonstrate significant differences between countries regarding donor screening algorithms based on precautionary principles and, consequently, a decrease in the donor pool, already constrained by a long list of contraindications. Fundamental studies are needed to determine the risk of SARS-CoV-2 transmission by corneal transplantation and guide evidence-based recommendations for donor selection to justify their substantial medical and economic impact.
BACKGROUND:Insulin-like growth factor 1 (IGF-1) was found to stimulate Schwann cell mitosis. Exogenous IGF-1 may improve nerve regeneration after cryopreservation.
OBJECTIVE:To evaulate the effect of ...intraneural administration of IGF-1 in cryopreserved nerve isografts.
METHODS:Eighteen millimeter grafts were used for bridging an 18-mm defect in the rat sciatic nerve. A total of 57 rats were randomly divided into three groups(1) autograft (Group 1); (2) cryopreserved isograft (Group 2); (3) cryopreserved isograft with intraneural IGF-1 administration (Group 3). 12 weeks after surgery, functional recovery (Sciatic functional index SFI, Swing speed SS, nerve conduction velocity NCV, amplitude of compound motor action potentials CMAP, and gastrocnemius muscle index GMI) and nerve regeneration (myelin sheath area, total fiber counts, fiber density, and fiber width) were all evaluated.
RESULTS:The intraneural injection of IGF-1 significantly improved SFI and SS at weeks 10 and 12. There were no statistical differences between Groups 1 and 3 in any of the SFI or SS evaluations. CMAP and NCV in Group 1 were significantly higher than in Groups 2 and 3, and Group 3 had significantly higher CMAP and NCV compared to Group 2. No significant differences were found in fiber width. The number of nerve fibers, percentage of myelinated fibers, fiber density, and GMI was significantly higher in Group 1 compared to Group 2, but no significant differences were found between Groups 1 and 3.
CONCLUSION:The results show that intraneural injection of IGF-1 in an 18 mm cryopreserved isograft improve axonal regeneration and functional recovery.
Summary
Donation after circulatory death (DCD) has become an accepted practice in many countries and remains a focus of intense interest in the transplant community. The present study is aimed at ...providing a description of the current situation of DCD in European countries. Specific questionnaires were developed to compile information on DCD practices, activities and post‐transplant outcomes. Thirty‐five countries completed the survey. DCD is practiced in 18 countries: eight have both controlled DCD (cDCD) and uncontrolled DCD (uDCD) programs, 4 only cDCD and 6 only uDCD. All these countries have legally binding and/or nonbinding texts to regulate the practice of DCD. The no‐touch period ranges from 5 to 30 min. There are variations in ante and post mortem interventions used for the practice of cDCD. During 2008–2016, the highest DCD activity was described in the United Kingdom, Spain, Russia, the Netherlands, Belgium and France. Data on post‐transplant outcomes of patients who receive DCD donor kidneys show better results with grafts obtained from cDCD versus uDCD donors. In conclusion, DCD is becoming increasingly accepted and performed in Europe, importantly contributing to the number of organs available and providing acceptable post‐transplantation outcomes.
Our aim was to analyze the short‐ and long‐term function of kidneys procured from non‐ heart‐beating 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.
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.
Summary
Impact of training on end‐of‐life care (EOLC) and the deceased donation process in critical care physicians’ perceptions and attitudes was analysed. A survey on attitudes and perceptions of ...deceased donation as part of the EOLC process was delivered to 535 physicians working in critical care before and after completion of a online training programme (2015–17). After training, more participants agreed that nursing staff should be involved in the end‐of‐life decision process (P < 0.001) and that relatives should not be responsible for medical decisions (P < 0.001). Postcourse, more participants considered ‘withdrawal/withholding’ as similar actions (P < 0.001); deemed appropriate the use of pre‐emptive sedation in all patients undergoing life support treatment adequacy (LSTA; P < 0.001); and were favourable to approaching family about donation upon LSTA agreement, as well as admitting them in the intensive care unit (P < 0.001) to allow the possibility of donation. Education increased the number of participants prone to initiate measures to preserve the organs for donation before the declaration of death in patients undergoing LSTA (P < 0.001). Training increased number of positive terms selected by participants to describe donation after brain and circulatory death. Training programmes may be useful to improve physicians’ perception and attitude about including donation as part of the patient’s EOLC.
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