Functional shift with maintained regenerative potential following portal vein ligation

Selective portal vein ligation (PVL) allows the two-stage surgical resection of primarily unresectable liver tumours by generating the atrophy and hypertrophy of portally ligated (LL) and non-ligated lobes (NLL), respectively. To evaluate critically important underlying functional alterations, present study characterised in vitro and vivo liver function in male Wistar rats (n = 106; 210-250 g) before, and 24/48/72/168/336 h after PVL. Lobe weights and volumes by magnetic resonance imaging confirmed the atrophy-hypertrophy complex. Proper expression and localization of key liver transporters (Ntcp, Bsep) and tight junction protein ZO-1 in isolated hepatocytes demonstrated constantly present viable and well-polarised cells in both lobes. In vitro taurocholate and bilirubin transport, as well as in vivo immunohistochemical Ntcp and Mrp2 expressions were bilaterally temporarily diminished, whereas LL and NLL structural acinar changes were divergent. In vivo bile and bilirubin-glucuronide excretion mirrored macroscopic changes, whereas serum bilirubin levels remained unaffected. In vivo functional imaging (indocyanine-green clearance test; (99mTc)-mebrofenin hepatobiliary scintigraphy; confocal laser endomicroscopy) indicated transitionally reduced global liver uptake and -excretion. While LL functional involution was permanent, NLL uptake and excretory functions recovered excessively. Following PVL, functioning cells remain even in LL. Despite extensive bilateral morpho-functional changes, NLL functional increment restores temporary declined transport functions, emphasising liver functional assessment

The flight feather moult pattern of the bearded vulture (Gypaetus barbatus).

Moult is an extremely time-consuming and energy-demanding task for large birds. In addition, there is a trade-off between the time devoted to moulting and that invested in other activities such as breeding and/or territory exploration. Moreover, it takes a long time to grow a long feather in large birds, and large birds that need to fly while moulting cannot tolerate large gaps in the wing, but only one or two simultaneously growing feathers. As a consequence, large birds take several years to complete a full moult cycle, and they resume the moult process during suboptimal conditions. A clear example of this pattern is the Bearded Vulture (Gypaetus barbatus), which needs 2-3 years for changing all flight feathers. Here we describe the sequence, extent, and timing of moult of 124 Bearded Vultures in detail for the first time. We found that extent and timing of flight feather moult was different between age classes. Subadults (from 3rd to 5th calendar year) started moult, on average, in early March, whereas adults only started moult, on average, in late April, possibly due to breeding requirements. Second calendar year individuals delayed onset of moult until the middle of May. In general, the moult lasted until November, and although adults started to moult later than subadults, they moulted more feathers. Subadults needed 3 years for moulting all flight feathers, whereas adults normally completed it in 2 years

Induction and transmission of oncogene-induced senescence

Senescence is a cellular stress response triggered by diverse stressors, including oncogene activation, where it serves as a bona-fide tumour suppressor mechanism. Senescence can be transmitted to neighbouring cells, known as paracrine secondary senescence. Secondary senescence was initially described as a paracrine mechanism, but recent evidence suggests a more complex scenario involving juxtacrine communication between cells. In addition, single-cell studies described differences between primary and secondary senescent end-points, which have thus far not been considered functionally distinct. Here we discuss emerging concepts in senescence transmission and heterogeneity in primary and secondary senescence on a cellular and organ level