Evaluation of the activity of the immune system and age-related tissue markers in Turquoise killifish \ud (Nothobranchius furzeri, Jubb 1971) \ud and their role in cell ageing\ud

Currently the Turquoise Killifish is considered the best animal model suitable for aging research. \ud This annual fish, from south east Africa, shows an exceptionally adaptive behaviour to dry periods: indeed, due to this extreme environmental characteristics, the life cycle of Nothobranchius furzeri is very fast, with an average lifespan of just about 8-9 weeks, making this species (more similar to highly developed vertebrates than nematodes or fruit flies) highly practical for aging studies. \ud The present study has evaluated the activity of the immune system as well as the expression of AGE-RAGE system, cell-damage related proteins (Bcl2, p53), mitosis activity marker (PCNA), and pro-apoptosis activity by T.U.N.E.L. method on the liver of four lifespan-specific strains of Turquoise Killifish (Nothobranchius furzeri, Jubb 1971), correlating the results with aging processes and tumor incidence. Some groups underwent caloric restriction in order to module their expected lifespan.\ud The results demonstrated an increase of age-related lesions along with the age in all the strains tested, due to a decrease of cellular-turn-over. This aspect was also influenced by the strain of the fish: longest lifespan strains showed later the similar lesions than short lifespan strains. Moreover caloric restriction groups showed lower incidence and severity of hepatic degeneration than control groups. Furthermore, there was a linear correspondence between the age of the model and its expected lifespan with the incidence and severity of neoplasm. The same relationship could be found in the expression of cell-damage related proteins (p53, Bcl2), age-related markers (AGE-RAGE system) and pro-apoptosis activity, as well as in the development of neoplasms. These results demonstrated the high feasibility of this fish as an excellent model to study the effects of aging processes and cancer genesis.\u

A Novel Electrochemical Flow-Cell for Operando XAS Investigations On X-ray Opaque Supports

Improvement of electrochemical technologies is one of the most popular topics in the field of renewable energy. However, this process requires a deep understanding of the electrode electrolyte interface behavior under operando conditions. X-ray absorption spectroscopy (XAS) is widely employed to characterize electrode materials, providing element-selective oxidation state and local structure. Several existing cells allow studies as close as possible to realistic operating conditions, but most of them rely on the deposition of the electrodes on conductive and X-ray transparent materials, from where the radiation impinges the sample. In this work, we present a new electrochemical flow-cell for operando XAS that can be used with X-ray opaque substrates, since the signal is effectively detected from the electrode surface, as the radiation passes through a thin layer of electrolyte. The electrolyte can flow over the electrode, reducing bubble formation and avoiding strong reactant concentration gradients. We show that high-quality data can be obtained under operando conditions, thanks to the high efficiency of the cell from the hard X-ray regime down to 4 keV. We report as a case study the operando XAS investigation at the Fe and Ni K-edges on Ni-doped maghemite films, epitaxially grown on Pt substrates. The effect of the Ni content on the catalytic performances for the oxygen evolution reaction is discussed.Comment: 11 pages, 9 figures, available supporting informatio

2021 Taxonomic update of phylum Negarnaviricota (Riboviria: Orthornavirae), including the large orders Bunyavirales and Mononegavirales.

Correction to: 2021 Taxonomic update of phylum Negarnaviricota (Riboviria: Orthornavirae), including the large orders Bunyavirales and Mononegavirales. Archives of Virology (2021) 166:3567–3579. https://doi.org/10.1007/s00705-021-05266-wIn March 2021, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was amended and emended. The phylum was expanded by four families (Aliusviridae, Crepuscuviridae, Myriaviridae, and Natareviridae), three subfamilies (Alpharhabdovirinae, Betarhabdovirinae, and Gammarhabdovirinae), 42 genera, and 200 species. Thirty-nine species were renamed and/or moved and seven species were abolished. This article presents the updated taxonomy of Negarnaviricota as now accepted by the ICTV.This work was supported in part through Laulima Government Solutions, LLC prime contract with the US National Institute of Allergy and Infectious Diseases (NIAID) under Contract No. HHSN272201800013C. J.H.K. performed this work as an employee of Tunnell Government Services (TGS), a subcontractor of Laulima Government Solutions, LLC under Contract No. HHSN272201800013C. This work was also supported in part with federal funds from the National Cancer Institute (NCI), National Institutes of Health (NIH), under Contract No. 75N91019D00024, Task Order No. 75N91019F00130 to I.C., who was supported by the Clinical Monitoring Research Program Directorate, Frederick National Lab for Cancer Research. This work was also funded in part by Contract No. HSHQDC-15-C-00064 awarded by DHS S&T for the management and operation of The National Biodefense Analysis and Countermeasures Center, a federally funded research and development center operated by the Battelle National Biodefense Institute (V.W.); and NIH contract HHSN272201000040I/HHSN27200004/D04 and grant R24AI120942 (N.V., R.B.T.). S.S. acknowledges partial support from the Special Research Initiative of Mississippi Agricultural and Forestry Experiment Station (MAFES), Mississippi State University, and the National Institute of Food and Agriculture, US Department of Agriculture, Hatch Project 1021494. Part of this work was supported by the Francis Crick Institute which receives its core funding from Cancer Research UK (FC001030), the UK Medical Research Council (FC001030), and the Wellcome Trust (FC001030).S

2021 Taxonomic update of phylum Negarnaviricota (Riboviria: Orthornavirae), including the large orders Bunyavirales and Mononegavirales.

In March 2021, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was amended and emended. The phylum was expanded by four families (Aliusviridae, Crepuscuviridae, Myriaviridae, and Natareviridae), three subfamilies (Alpharhabdovirinae, Betarhabdovirinae, and Gammarhabdovirinae), 42 genera, and 200 species. Thirty-nine species were renamed and/or moved and seven species were abolished. This article presents the updated taxonomy of Negarnaviricota as now accepted by the ICTV

Local ordering of nanostructured Pt probed by multiple-scattering XAFS

International audienceWe present detailed results of a multiple-scatterin

Performance of a fuel cell optimized for in situ X-ray absorption experiments

A commercial fuel cell has been successfully modified to carry out X-ray absorption spectroscopy (XAS) measurements under optimized in operando conditions. The design is conceived for the performance of XAS experiments in transmission mode over a wide range of X-ray energies above 6 keV, owing to the reduced absorption of the cell. The wide angular aperture allows the collection of XAS in fluorescence mode and of X-ray diffraction patterns when needed. Details of the design of the cell and its performances are given. The quality of the extended X-ray absorption fine-structure spectra under working conditions has been verified at the ESRF and ELETTRA synchrotron radiation facilities, showing that relatively fast and low-noise transmission measurements on electrodes over a wide range of catalyst concentrations and energies are feasible

Local structural and chemical ordering of nanosized Pt3±δCo probed by multiple-scattering x-ray absorption spectroscopy

International audienceThis work reports a detailed investigation of the local structure and chemical disorder of a Pt3±δCo thin film and Pt3±δCo nanoparticles. We have used a combination of techniques including x-ray absorption spectroscopy (XAS), x-ray diffraction (XRD), and high-resolution transmission electron microscopy (TEM). High-quality XAS spectra at the Co K edge and Pt L3 edge have been analyzed using double-edge multiple-scattering data analysis. Structural extended x-ray absorption fine structure (EXAFS) refinements have been performed accounting for the reduction of the coordination numbers and degeneracy of three-atom configurations, resulting from the measured size distribution and stoichiometry. The important effect of chemical ordering on pair and three-atom configurations has been studied using computer simulations based on a simple model accounting for substitutional disorder, defined by an order parameter s. It has been found that individual EXAFS signals related to the minority species (Co) are extremely sensitive to substitutional disorder so their intensities, especially those of the collinear three-atom configurations, can be used as a measure of the ordering level. The thin film has been found to be chemically disordered (s 0.4), in agreement with previous estimates. The Pt3±δCo nanoalloy has been found to be partially ordered (s = 0.6 ± 0.1) while the local structure around Co atoms is characterized by a higher level of structural disorder as compared to the bulk-like thin film. The robust approach for nanomaterial characterization used in this work combining different techniques can, in principle, be applied for structural refinements of any binary nanocrystalline functional system

Comparison of captive lifespan, age-associated liver neoplasias and age-dependent gene expression between two annual fish species: Nothobranchius furzeri and Nothobranchius korthause

Nothobranchius is a genus of annual fish broadly distributed in South-Eastern Africa and found into temporary ponds generated during the rain seasons and their lifespan is limited by the duration of their habitats. Here we compared two Nothobranchius species from radically different environments: N. furzeri and N. korthausae. We found a large difference in life expectancy (29- against 71-weeks of median life span, 40- against 80-weeks of maximum lifespan, respectively), which correlates with a diverse timing in the onset of several age dependent processes: our data show that N. korthause longer lifespan is associated to retarded onset of age-dependent liver-neoplasia and slower down-regulation of collagen 1 alpha 2 (COL1A2) expression in the skin. On the other hand, the expression of cyclin B1 (CCNB1) in the brain was strongly age-regulated, but with similar profiles in N. furzeri and N. korthausae. In conclusion, our data suggest that the different ageing rate of two species of the same genus could be used as novel tool to investigate and better understand the genetic bases of some general mechanism leading to the complex ageing process, providing a strategy to unravel some of the genetic mechanisms regulating longevity and age-associate pathologies including neoplasias