Multivalent manganese-mediated synergistic aerobic denitrification boost nitrogen removal in oligotrophic aquatic systems: Insight into microbial functional and metabolic complementarity.

Mimetic violence and wartime organ donation between Israeli Jews and Palestinians.

Liver Transplantation Following Organ Donation After Medical Assistance in Dying: One Step Further.

Strongyloides stercoralis is a parasitic nematode endemic in tropical and subtropical regions, including parts of the southeastern United States, that can be transmitted via organ donation. As of October 2025, the Organ Procurement and Transplant Network implemented new policy for screening in deceased US organ donors to reduce the risk for donor-derived Strongyloides infection. To assess the potential effect of policy changes, we reviewed investigations of suspected transplant-related strongyloidiasis in the United States conducted by the Centers for Disease Control and Prevention and partners for solid organ transplants occurring during 2012-2024. During that period, 21 proven donor-derived strongyloidiasis cases originated from 15 unscreened donors. Of donors who were screened, 31 seropositive donors resulted in ivermectin prophylaxis for 77 recipients, none of whom had disease develop. Our findings support the effectiveness of universal organ donor screening and prophylactic ivermectin treatment of recipients to prevent donor-derived Strongyloides infection.

The Dutch Experience with Organ Donation After Euthanasia: Comparing DCD-V and DCD-III Lung Transplantation Outcomes

Perspectives of Caregivers of Kidney Transplant Recipients and Transplant Candidates About Kidneys From Donors With Hepatitis C Virus Infection.

Lung transplantation remains limited by donor organ scarcity. This review summarizes recent strategies with the direct potential to expand lung availability, including 10°C hypothermic preservation, donation after circulatory death (DCD), ex vivo lung perfusion (EVLP), and expanded utilization of elderly donors. Clinical translation of 10°C static preservation has enabled prolonged storage, including preservation for up to 24 h without clear adverse short- or intermediate-term consequences, and the prospect of semi-elective transplantation. Contemporary evidence supports broader use of DCD lungs, particularly controlled DCD, with reassuring long-term outcomes despite small differences in early risk in some cohorts; uncontrolled DCD remains promising in highly organized EVLP-based programs, whereas thoracoabdominal normothermic regional perfusion requires further prospective evaluation. EVLP continues to increase utilization of marginal lungs, and the largest single-center series reported outcomes comparable to conventional transplantation. In parallel, carefully selected septuagenarian and even octo-/nonagenarian donors have demonstrated encouraging short- and long-term clinical outcomes. Donor shortage in lung transplantation can be mitigated by combining logistics-extending preservation strategies, broader donor pathways, advanced graft assessment, and careful expansion of donor acceptance criteria. Standardized, prospective, multicenter clinical trials are still frequently lacking and represent an area for future improvement.

Seven new crystal structures of 3,6-bis(pyridin-2-yl)-1,2,4,5-tetrazine (2-bptz) and 3,6-bis(pyridin-4-yl)-1,2,4,5-tetrazine (4-bptz) were determined with inorganic halogen donors (I2 or I3-), organic halogen donors [1,4-diiodotetrafluroobenzene (p-F4DIB) or 1,3,5-trifluoro-2,4,6-triiodobenzene (1,3,5-TFTIB)], and the hydrogen-bond donor hydroquinone to investigate how pyridyl orientation and donor type influence supramolecular assembly. Structures formed with molecular iodine, namely, 2,2'-(1,2,4,5-tetrazine-3,6-diyl)dipyridinium bis(triiodide)-3,6-bis(pyridin-2-yl)-1,2,4,5-tetrazine-diiodine (1/1/1), C12H10N62+·2I3-·C12H8N6·I2 (1), and 4-[6-(pyridin-4-yl)-1,2,4,5-tetrazin-3-yl]pyridinium pentaiodide, C12H9N6+·I5- (2), are dominated by N-H...N hydrogen bonding, with pyridine protonation yielding distinct packing arrangements: 2-bptz forms stacked triads along the a axis, whereas 4-bptz assembles into chains of [H(4-bptz)]+ cations alternating with pentaiodide layers. Replacement of iodine with organoiodines in 3,6-bis(pyridin-2-yl)-1,2,4,5-tetrazine-1,4-diiodotetrafluorobenzene (1/1), C6F4I2·C12H8N6 (3), 3,6-bis(pyridin-4-yl)-1,2,4,5-tetrazine-1,4-diiodotetrafluorobenzene (1/1), C6F4I2·C12H8N6 (4), and 3,6-bis(pyridin-2-yl)-1,2,4,5-tetrazine-1,3,5-trifluoro-2,4,6-triiodobenzene (1/2), C6H4N3·C6F3I3 (5), shifts the primary interactions to C-I...N halogen bonding, producing one-dimensional staggered chains in 2-bptz and linear motifs in 4-bptz, with bifurcated C-I...N interactions in 5 involving both pyridine and tetrazine N atoms. Halogen-halogen and halogen-fluorine interactions further modulate packing and stacking orientations. Reactions with hydroquinone in 3,6-bis(pyridin-2-yl)-1,2,4,5-tetrazine-hydroquinine (2/1), 2C12H8N6·C6H6O2 (6), and 3,6-bis(pyridin-4-yl)-1,2,4,5-tetrazine-hydroquinine (1/1), C12H8N6·C6H6O2 (7), reveal the role of hydrogen bonding in long-range organization: 2-bptz forms discrete triads, whereas 4-bptz generates extended chains propagating through pyridine-phenol interactions. Pyridine-to-tetrazine plane-to-plane angles vary across structures, reflecting the influence of substitution pattern and donor type on molecular geometry. These results demonstrate that subtle changes in pyridyl orientation and the nature of halogen- or hydrogen-bond donors can direct the formation of distinct supramolecular architectures, providing a foundation for the rational design of tetrazine-based crystalline materials with tunable packing and noncovalent interactions.

The "next" standard for ABO genotyping.

Macrovesicular steatosis in liver transplant donors is associated with increased risk of poor outcomes. Prerecovery computed tomography (CT) is widely available but has substantial variability and requires expert interpretation. Automating CT-based steatosis assessment could streamline evaluation. We analyzed CT scans from a single organ procurement organization between 2019 and 2024 with biopsy reports. The primary outcome was macrovesicular steatosis ≥30%. The liver and spleen were automatically segmented. Predictive approaches included (1) clinical features only; univariable models using (2) liver attenuation, (3) liver-to-spleen ratio, and (4) liver-spleen difference; (5) radiomics (1130 features) with extreme gradient boosting; (6) a 2-step method combining liver-spleen difference with radiomics; and (7) a 3-dimensional convolutional neural network. Performance was evaluated with repeated stratified train/validation/test splits for >100 random seeds, using area under the receiver operating characteristic (AUROC) as the primary metric. A total of 147 CTs were included; 25.9% had ≥30% biopsy-proven macrovesicular steatosis, 11.6% were contrast-enhanced only, and 40.8% showed at least grade 1 fibrosis. Model performance ranged from an AUROC of 0.65 (interquartile range [IQR], 0.57-0.72) for the clinical-only model to 0.87 (IQR, 0.81-0.92) for the 2-step approach ( P = 0.028 relative to the clinical model). Univariable models achieved AUROCs of 0.81 (IQR, 0.78-0.82) for liver attenuation, 0.84 (IQR, 0.77-0.89) for liver-to-spleen ratio, and 0.83 (IQR, 0.78-0.90) for liver-spleen difference. An automated 2-step approach using radiomic features achieved strong performance in predicting donor macrovesicular steatosis. Such models could help support decision-making and expedite evaluation in the donor-offer process.

Efficacy of corticosteroid pretreatment in the management of deceased organ donors: A systematic review and meta-analysis.

Early life is essential for establishing memory T cells, which rapidly populate mucosal sites during infancy, although these nascent memory T cells are less protective than their adult counterparts. Here we used single-cell RNA sequencing of resting and CD3+CD28 antibody-stimulated T cells from lymphoid and mucosal tissues of infant (2-9 months) and adult (40-63 years) organ donors to investigate age-dependent mechanisms for functional regulation of human memory T cells. Infant CCL5+ effector memory T cells exhibited reduced effector function compared to adults. Transcription factor network analysis identified HELIOS and KLF6 as regulators of memory T cell states in infant and adult tissues, respectively. Using single-nucleus RNA sequencing, assay for transposase-accessible chromatin sequencing and CRISPR-Cas9 knockout, we defined HELIOS (IKZF2) as a critical regulator of the infant-specific transcriptional program in CCL5+ effector memory T cells and restricted effector function in SELL+CCR7+ naive and/or central memory T cells. Our findings reveal key mechanisms controlling T cell functional states in early life.

Lung transplantation is conspicuously resource intensive, yet the carbon footprint of solid organ transplantation, and lung transplantation in particular, remains relatively unmapped. Moreover, there is growing evidence that climate change adversely affects lung transplant recipients, directly and indirectly. This review explores opportunities to integrate sustainable practices across the lung transplantation pathway, with the dual aims of reducing environmental impact and reducing recipient morbidity and mortality. Published literature outlines mitigation strategies to reduce the drivers of climate change, and adaptation strategies to modify the hazardous effects of the climate crisis on healthcare services. Opportunities to create "green chains" of transplant care start with appropriate recipient and donor selection, with both elements optimised to maximise operative success and avoid donor organ discard. The peri-operative phase offers scope for decarbonisation via the reduction of anaesthetic gas emissions, green procurement, and waste reduction. In the post-transplant phase, enhanced recovery after surgery (ERAS) programmes feed into longer term surveillance and care delivery, with increasing opportunities for telemedicine and noninvasive allograft monitoring, to reduce travel-related emissions. The co-ordinated adoption of low-carbon, sustainable practices within lung transplantation offers a meaningful opportunity to reduce environmental harm, enhance healthcare infrastructure and workforce resilience, and improve patient outcomes in a patient cohort vulnerable to climate change. Lessons can be drawn from the global surgery movement; however, it remains the responsibility of transplant practitioners to foster a culture of environmental advocacy and to implement systematic measurement and targets for climate change and health indicators.

Organ transplantation remains the only curative treatment for end-stage organ failure. However, a critical shortage of donor organs presents a major challenge. Human induced pluripotent stem cell (hiPSC)-derived organoids represent a promising technology for generating transplantable human tissues. This study aimed to create functional and scalable tissue from hiPSC-derived liver organoids (hiPSC-LOs) by establishing an oxygenation system using a decellularized liver (DL), which retains the parenchymal and vascular extracellular matrix to support cell adhesion and medium perfusion. First, the culture condition of hiPSC-LOs was refined to enhance their engraftment in rat DLs. Next, an oxygenation system for hiPSC-LO-engrafted DLs (hiPSC-liver tissue [hiPSC-LT]) was established using perfusion of oxygen-enriched medium containing artificial red blood cells. Finally, the oxygenated hiPSC-LTs were transplanted onto the liver surface of immunodeficient mice. Functional hiPSC-LTs were successfully generated by infusing day 8 precultured hiPSC-LOs into DLs. Perfusion with oxygenated medium containing artificial red blood cells suppressed cell death and promoted hepatic function of hiPSC-LTs by mimicking the physiological oxygen concentration found in the fetal liver. Notably, oxygenated hiPSC-LTs demonstrated improved engraftment in vivo, as evidenced by increased human albumin levels in recipient mouse serum compared with nonoxygenated controls. The oxygenation system using DLs and artificial red blood cells effectively supported the generation of transplantable, functional hiPSC-LT. This culture strategy enhances both the enlargement and functionality of hiPSC-organoids and represents a promising step toward developing alternatives to conventional organ transplantation.

Advances in organ transplantation and mechanical circulatory support technologies have deepened the ethical complexity of care for critically ill patients across the donation-transplant continuum, especially at the end-of-life. This narrative review is structured around four clinical scenarios faced by bedside intensivists: patients awaiting transplantation, patients for whom transplant is no longer an option, patients who may become organ donors, and transplant patients at the end-of-life. Across these contexts, clinicians must navigate prognostic uncertainty, steward scarce resources, and address potentially nonbeneficial treatment, while respecting patient values. Through case-based analysis, we offer practical ethical guidance and emphasize the critical role of skilled communication, ethics consultation, and palliative care in supporting bedside decision-making.

Aortic dissection (AD) caused by the intimal tear would progress into the separation of aortic media, leading to devastating sequelae. Quantifying the mechanical and histological changes in aortic intima-media (IM) tissue during the AD development would advance our understanding of the mechanism behind the disease initiation for its prevention and management. Twenty-eight ascending aortic specimens were harvested from 19 patients with type A AD and 9 organ donors to obtain 120 aortic IM tissue samples. Uniaxial tensile experiments were performed on the samples until they failed, and their ultimate stress and stretch data at the time of failure were recorded. Additionally, an extra subsample was cut from each aortic specimen to perform the histological staining to quantify the contents of elastic and collagen fibers. Our statistical results showed that the ultimate stress and stretch of the dissected aortic IM samples were significantly lower than those of normal ones. Furthermore, a positive correlation between the elastic fiber content and ultimate stretch in aortic IM was found. Combining these findings, it suggests that reduced elastic fiber content in aortic IM tissue of the diseased group impairs its ability to withstand high stress and stretch conditions, thereby predisposing to AD.

As the chronic shortage of human donor organs becomes an undeniable clinical reality, xenotransplantation has transitioned from a theoretical concept to the threshold of clinical integration. Recent successful pig-to-human kidney trials signify a pivotal milestone, shifting the scientific focus from feasibility to long-term sustainability and systemic implementation. This review critically evaluates the current status and future trajectory of xenotransplantation, challenging the "more is better" paradox of genetic engineering. It emphasizes the minimum viable edit set and the physiological superiority of miniature pigs overgrowth hormone receptor knockout models. Furthermore, the paper outlines a Korean-style governance model, integrating advanced digital transformation and specialized infrastructure. Key proposed strategies include (1) digital monitoring: implementing a noninvasive surveillance system utilizing donor-derived cell-free DNA, digital twins, and AI-driven early warning systems; (2) blockchain integration: establishing data integrity and tokenomics-based patient compliance through a sovereign medical coin system to incentivize lifelong surveillance; (3) infrastructure innovation: introducing the Hybrid Hospital Model, featuring a sterile barrier window between porcine and human surgical suites to achieve a zero-ischemia workflow. Finally, the study stresses the necessity of a Xenotransplantation Special Act and the collaboration between public organ procurement organizations and specialized private contract research organizations. By combining genetic minimalism and a robust legal framework, South Korea can establish itself as a global standard setter, transforming xenotransplantation into a standardized, manageable precision medical service.

Heart transplantation is limited by donor organ shortage and ischemia-reperfusion injury, particularly in donation after circulatory death (DCD). Thoracoabdominal normothermic regional perfusion (TANRP) enables in situ myocardial resuscitation and assessment, while beating-heart strategies further reduce ischemic exposure. We report a DCD heart transplantation performed using in situ TANRP followed by beating-heart procurement, short-distance transfer without coronary flow, and implantation under continuous normothermic blood perfusion using the recipient cardiopulmonary bypass circuit. Graft ischemic time was near zero. Immediate graft function was achieved, and no early postoperative complications were observed. This case supports the technical feasibility of an almost fully ischemia-sparing, beating-heart transplantation strategy after TANRP in DCD donation. Further experience is required to assess reproducibility, safety, and clinical impact.

Deceased donor organ procurement presents distinct ethical challenges for transplant teams, yet moral distress among these professionals remains understudied, particularly in low-donation settings. This study measured moral distress levels among organ procurement team members at a Serbian tertiary centre and examined factors associated with distress intensity. This cross-sectional study administered a transplantation-adapted Moral Distress Scale-Revised (MDS-R) to 22 active transplant team members at the University Clinical Centre of Vojvodina in 2023 (response rate 78.6%, 22/28). The adapted Serbian-language instrument demonstrated excellent internal consistency (Cronbach's α = 0.89); however, it has not undergone full psychometric validation for transplantation contexts. We analysed MDS-R total composite scores (frequency × intensity, range 0-336) across professional groups and examined correlations with demographic and professional variables using non-parametric statistics. Mean MDS-R total composite score was 82.4 ± 31.8 (range 38-132), suggesting substantial moral distress in this sample. Compared with published point estimates from ICU (69.5) and emergency settings (71.2), our estimate was numerically higher, but the 95% CI overlapped both reference values; cross-study comparisons are descriptive only. Significant differences emerged across professional groups (Kruskal-Wallis H = 8.73, df = 4, p = 0.013, η² = 0.28): vascular surgeons reported the highest observed scores (96.4 ± 27.3), though with only four participants this finding requires cautious interpretation. Post-hoc analysis revealed a significant difference between vascular surgeons and transplant coordinators (adjusted p = 0.018). Years of transplantation experience correlated negatively with distress (Spearman's ρ = - 0.47, 95% bootstrap CI [-0.73, - 0.12], p = 0.02). Highest-intensity distress items in the full sample were family communication dilemmas (3.5 ± 0.8) and donor body objectification concerns (3.4 ± 0.9). Nearly 60% of participants reported having considered leaving transplantation; intention to leave correlated with MDS-R scores (Spearman's ρ = 0.52, bootstrap 95% CI [0.18, 0.76], p = 0.01), although reasons for considering departure were not systematically collected. Organ procurement team members in this low-donation setting reported substantial moral distress. While vascular surgeons had the highest observed scores, this finding may reflect role-specific factors, demographic differences, or other unmeasured confounders, and requires confirmation in larger samples. The association between moral distress and self-reported intention to leave transplantation, though exploratory, highlights the need for further investigation of retention-focused support strategies in procurement teams.

Solid organ transplantation remains limited by the availability and quality of donor organs. Despite advances in donor management and allocation policy, a substantial proportion of recovered organs are discarded, and increasing reliance on extended-criteria and donation after circulatory death donors introduces additional uncertainty regarding graft viability. Traditional preservation using static cold storage provides a limited opportunity to assess organ function or intervene therapeutically before transplantation. Recent advances in machine perfusion technologies have begun to reshape this paradigm by enabling donor organs to be maintained and evaluated ex vivo. Normothermic perfusion platforms allow real-time physiologic assessment and biochemical monitoring, while hypothermic approaches primarily support preservation with more limited capacity for functional evaluation. These capabilities have created the foundation for the development of organ assessment and repair centers (ARCs), specialized platforms designed to centralize perfusion-based organ evaluation and potential rehabilitation. This overview examines the rationale for regionalized ARC systems and their potential to expand donor organ utilization while improving graft preservation and viability assessment. We discuss the clinical and logistical advantages of centralized perfusion platforms, including mitigation of ischemia/reperfusion injury, improved viability assessment, centralized expertise, integrated research infrastructure, and opportunities for organ-directed therapeutic interventions. We also examine the practical challenges associated with ARC implementation, including financial costs, infrastructure requirements, regulatory oversight, and logistical coordination across transplant networks. As machine perfusion technologies continue to evolve, ARCs may provide the infrastructure needed to integrate advanced preservation, diagnostics, and therapeutic interventions into routine transplant practice, enabling more effective utilization of the donor organ pool.