Parasites of marine and fresh water fishes, belonging to the groups of the Protozoa, Trematoda, Acanthocephala, and Cestoda, are recorded from the Netherlands. Several species are discussed.
Liver transplantation is the only effective treatment for end-stage liver disease, but absolute donor shortage remains a limiting factor. Recent advances in tissue engineering focus on generation of native extracellular matrix (ECM) by decellularized complete livers in animal models. Although proof of concept has been reported for human livers, this study aims to perform whole liver decellularization in a clinically relevant series using controlled machine perfusion. In this study, we describe a mild nondestructive decellularization protocol, effective in 11 discarded human whole liver grafts to generate constructs that reliably maintain hepatic architecture and ECM components using machine perfusion, while completely removing cellular DNA and RNA. The decellularization process preserved the ultrastructural ECM components confirmed by histology, electron microscopy, and proteomic analysis. Anatomical characteristics of the native microvascular network and biliary drainage of the liver were confirmed by contrast computed tomography scanning. Decellularized vascular matrix remained suitable for normal suturing and no major histocompatibility complex molecules were detected, suggesting absence of allo-reactivity when used for transplantation. After extensive washing, decellularized scaffolds were nontoxic for cells after reseeding human mesenchymal stromal or umbilical vein endothelial endothelium cells. Indeed, evidence of effective recellularization of the vascular lining was obtained. In conclusion, we established an effective method to generate clinically applicable liver scaffolds from human discarded whole liver grafts and show proof of concept that reseeding of normal human cells in the scaffold is feasible. This supports new opportunities for bioengineering of transplantable grafts in the future.
The cover image is based on the Article Scaffolds obtained from decellularized human extrahepatic bile ducts support organoids to establish functional biliary tissue in a dish by Jorke Willemse et al., https://doi.org/10.1002/bit.27613.
The incidence of Proteocephalus filicollis in Pungitius pungitius, Gasterosteus aculeatus f. hemigymnus and Gasterosteus aculeatus f. trachurus has been studied. It is very low in both forms of Gasterosteus, but 16% of Pungitius was infected. The monthly examination of minimally 27 and maximally 223 Pungitius pungitius indicates that an annual cycle exists neither in the incidence nor in genital development. It seems probable that Proteocephalus filicollis in Pungitius pungitius is less affected by low temperatures than worms of the same species in Gasterosteus aculeatus. Reference is made to intercurrent helminth infections.
In silver eels the arteries supplying the pectoral girdles and fins, arise from a common trunk which branches off from the dorsal aspect of the dorsal aorta, while the origin of this trunk is found at the ventral aspect of the aorta in the leptocephalus larva. The rearrangement of the origin of this trunk is mainly accomplished during metamorphosis, and is related to the rearrangement of the junction of the epibranchial arteries and the aorta. The processes of remodelling the wall of the vessels involved in these rearrangements are discussed against the background of data on similar remodelling, accompanying the rearrangement of arterial junctions during the development of higher vertebrates.
