Fatty acids from the cyanobacterium Microcystis aeruginosa with potent inhibitory effects on fish gill Na+/K+-ATPase activity

Contains fulltext : 14258.pdf (publisher's version ) (Open Access

Evaluation of planar silicon pixel sensors with the RD53A readout chip for the Phase-2 Upgrade of the CMS Inner Tracker

The Large Hadron Collider at CERN will undergo an upgrade in order to increase its luminosity to 7.5 × 10³⁴ cm⁻²s⁻¹. The increased luminosity during this High-Luminosity running phase, starting around 2029, means a higher rate of proton-proton interactions, hence a larger ionizing dose and particle fluence for the detectors. The current tracking system of the CMS experiment will be fully replaced in order to cope with the new operating conditions. Prototype planar pixel sensors for the CMS Inner Tracker with square 50 μm × 50 μm and rectangular 100 μm × 25 μm pixels read out by the RD53A chip were characterized in the lab and at the DESY-II testbeam facility in order to identify designs that meet the requirements of CMS during the High-Luminosity running phase. A spatial resolution of approximately 3.4 μm (2 μm) is obtained using the modules with 50 μm × 50 μm (100 μm × 25 μm) pixels at the optimal angle of incidence before irradiation. After irradiation to a 1 MeV neutron equivalent fluence of Φeq = 5.3 × 10¹⁵ cm⁻², a resolution of 9.4 μm is achieved at a bias voltage of 800 V using a module with 50 μm × 50 μm pixel size. All modules retain a hit efficiency in excess of 99% after irradiation to fluences up to 2.1 × 10¹⁶ cm⁻². Further studies of the electrical properties of the modules, especially crosstalk, are also presented in this paper

The effects of cyanobacteria and the cyanobacterial toxin microcystin-LR on Ca2+ transport and Na+/K+-atpase in tilapia gills

Contains fulltext : 29004.pdf (publisher's version ) (Open Access

Evidence of Common Cadmium and Copper Uptake Routes in Zebrafish <i>Danio rerio</i>

Cadmium and copper accumulations in gills of zebrafish were measured during a 48 h exposure to 0.025 μM ¹⁰⁶Cd and 0.05 or 0.5 μM ⁶⁵Cu as a single metal or their mixtures. The gill transcript levels of genes involved in the transport of Cu (CTR1 and ATP7A), Na (NHE-2), Ca (ECaC), divalent metals (DMT1), and Zn (ZIP8) were also compared between treatments at 24 and 48 h. Cd uptake was significantly suppressed in the presence of Cu, indicating interaction between Cu and Cd at uptake sites, but Cu uptake was unaffected by Cd. The decrease in Cd accumulation rates in the presence of Cu was associated with an increase in transcript abundance of ECaC at 24 h and DMT1 at 48 h and a decrease in Zip8 transcript levels, all known as routes for Cd uptake. Fish exposed to 0.5 μM ⁶⁵Cu show an increase in gill ATP7a transcript abundance, suggesting that Cu is removed from the gill and is transferred to other organs for detoxification. A reduction in gill CTR1 transcript abundance was observed during the Cu–Cd exposure; this may be a regulatory mechanism to reduce Cu loading if Cu is entering the gills by other uptake routes, such as ECaC and DMT1

ATP-Dependent Silver Transport across the Basolateral Membrane of Rainbow Trout Gills

Silver has been shown to be extremely toxic to freshwater teleosts, acting to inhibit Na+ uptake at the gills, due to the inactivation of branchial Na+/K+-ATPase activity. However, the gills are also a route by which silver may enter the fish. Therefore, this study focuses on the mechanism of transport of this nonessential metal across the basolateral membrane of the gill cell, using basolateral membrane vesicles (BLMV) prepared from the gills of freshwater rainbow trout. Uptake of silver by BLMV was via a carrier-mediated process, which was ATP-dependent, reached equilibium over time, and followed Michaelis–Menten kinetics, with maximal transport capacity (Vmax) of 14.3 ± 5.5 (SE) nmol mg membrane protein-1 min-1 and an affinity (Km) of 62.6 ± 43.7 μM, and was inhibited by 100 μM sodium orthovanadate (Na3VO4). The ionophore monensin (10 μM) released transported silver from the BLMV. Acylphosphate intermediates, of a 104 kDa size, were formed from the BLMV preparations in the presence of ATP plus Ag. These results demonstrate that there is a P-type ATPase present in the basolateral membrane of the gills of rainbow trout that can actively transport silver, a process which will remove this heavy metal from its site of toxic action, the gill

Stress and innate immunity in carp: Corticosteroid receptors and pro-inflammatory cytokines

Contains fulltext : 70948.pdf (postprint version ) (Open Access)10 p

Cortisol protects against copper induced necrosis and promotes apoptosis in fish gill chloride cells in vitro

Contains fulltext : 14259.pdf (publisher's version ) (Closed access