Bafilomycin A1 activates respiration of neuronal cells via uncoupling associated with flickering depolarization of mitochondria

Bafilomycin A1 (Baf) induces an elevation of cytosolic Ca2+ and acidification in neuronal cells via inhibition of the V-ATPase. Also, Baf uncouples mitochondria in differentiated PC12 (dPC12), dSH-SY5Y cells and cerebellar granule neurons, and markedly elevates their respiration. This respiratory response in dPC12 is accompanied by morphological changes in the mitochondria and decreases the mitochondrial pH, Ca2+ and ΔΨm. The response to Baf is regulated by cytosolic Ca2+ fluxes from the endoplasmic reticulum. Inhibition of permeability transition pore opening increases the depolarizing effect of Baf on the ΔΨm. Baf induces stochastic flickering of the ΔΨm with a period of 20 ± 10 s. Under conditions of suppressed ATP production by glycolysis, oxidative phosphorylation impaired by Baf does not provide cells with sufficient ATP levels. Cells treated with Baf become more susceptible to excitation with KCl. Such mitochondrial uncoupling may play a role in a number of (patho)physiological conditions induced by Baf

Lipid spin labeling and NMR study of interaction between polyadenylic acid: polyuridilic acid duplex and egg phosphatidylcholine liposomes. Evidence for involvement of surface groups of bilayer, phosphoryl groups and metal cations

Hydrophobic spin labeling of fatty acyl residues at 5-, 12- or 16-positions of phosphatidylcholine liposomes reveals the involvement of surface moieties of bilayer (up to fifth carbon atom of fatty acyl) into interaction with polyadenylic acid: polyuridilic acid duplex and magnesium ions.31P NMR spectra of this system demonstrate participation of nucleotide phosphoryl groups and metal cations in ternary complexation. © 1994 Springer

Lipid spin labeling and NMR study of interaction between polyadenylic acid: polyuridilic acid duplex and egg phosphatidylcholine liposomes. Evidence for involvement of surface groups of bilayer, phosphoryl groups and metal cations

Hydrophobic spin labeling of fatty acyl residues at 5-, 12- or 16-positions of phosphatidylcholine liposomes reveals the involvement of surface moieties of bilayer (up to fifth carbon atom of fatty acyl) into interaction with polyadenylic acid: polyuridilic acid duplex and magnesium ions.31P NMR spectra of this system demonstrate participation of nucleotide phosphoryl groups and metal cations in ternary complexation. © 1994 Springer

SPES4-pi:installation for exclusive study of nuclear reactions

EI SEP PHASE ACCThe paper describes the spectrometric system “SPES4–$\pi$” used at the National Laboratory Saturne (CE Saclay, France) for the exclusive study of the baryon resonance excitation in inelastic α and d scattering on the proton, as well as coherent pion production in charge exchange reactions. The system consists of the magnetic spectrometer SPES4 and two wide-aperture position-sensitive detector arrays, equipped with wire chambers and scintillator hodoscopes, installed around a large-gap C-shape dipole magnet

Hyperthermal energy distribution functions of the adspecies in recombinative adsorption at catalytic surfaces and their relevance to ‘hot atom’ reactions

We report on the modeling of the energy distribution functions of the adspecies in diatom formation at catalytic surfaces under steady state conditions. To this end master equations are employed, in the case of either continuous or discrete set of adatom energy levels in the adsorption potential well, and the impact of the distribution function on reaction rate investigated. The transition from thermal to hyperthermal reaction rates has been studied as a function of rate coefficients for recombination and energy dissipation processes. Experimental data available from the literature, have been analysed in the framework of the theoretical model. It is shown that hyperthermal energy distribution functions entail a “hot atom” reaction mechanism