Bi-organ paired exchange-Sentinel case of a liver-kidney swap.

Organ transplantation is the optimal treatment for patients with end stage liver disease and end stage renal disease. However, due to the imbalance in the demand and supply of deceased organs, most transplant centers worldwide have consciously pursued a strategy for living donation. Paired exchanges were introduced as a means to bypass various biologic incompatibilities (blood- and tissue-typing), while expanding the living donor pool. This shift in paradigm has introduced new ethical concerns that have hitherto been unaddressed, especially with nondirected, altruistic living donors. So far, transplant communities have focused efforts on separate liver- and kidney-paired exchanges, whereas the concept of a transorgan paired exchange has been theorized and could potentially facilitate a greater number of transplants. We describe the performance of the first successful liver-kidney swap.

Network analysis of social changes in a captive chimpanzee community following the successful integration of two adult groups.

Chimpanzees are highly territorial and have the potential to be extremely aggressive toward unfamiliar individuals. In the wild, transfer between groups is almost exclusively completed by nulliparous females, yet in captivity there is often a need to introduce and integrate a range of individuals, including adult males. We describe the process of successfully integrating two groups of chimpanzees, each containing 11 individuals, in the Budongo Trail facility at the Royal Zoological Society of Scotland's Edinburgh Zoo. We use social network analysis to document changes in group dynamics within this population over the 16 months following integration. Aggression rates were low overall and members of the two original groups engaged in significantly fewer aggressive interactions over time. Association and grooming data indicate that relationships between members of the original groups became stronger and more affiliative with time. Despite these positive indicators the association data revealed the continued existence of two distinct subgroups, a year after integration. Our data show that when given complex space and freedom to exhibit natural fission-fusion groupings, in which the chimpanzees choose whom they wish to associate and interact with, the building of strong affiliative relationships with unfamiliar individuals is a very gradual process.