32 research outputs found
The Second Fermi Large Area Telescope Catalog of Gamma-Ray Pulsars
This catalog summarizes 117 high-confidence 0.1 GeV gamma-ray pulsar detections using three years of data
acquired by the Large Area Telescope (LAT) on the Fermi satellite. Half are neutron stars discovered using LAT
data through periodicity searches in gamma-ray and radio data around LAT unassociated source positions. The 117
pulsars are evenly divided into three groups: millisecond pulsars, young radio-loud pulsars, and young radio-quiet
pulsars. We characterize the pulse profiles and energy spectra and derive luminosities when distance information
exists. Spectral analysis of the off-peak phase intervals indicates probable pulsar wind nebula emission for four
pulsars, and off-peak magnetospheric emission for several young and millisecond pulsars.We compare the gammaray
properties with those in the radio, optical, and X-ray bands.We provide flux limits for pulsars with no observed
gamma-ray emission, highlighting a small number of gamma-faint, radio-loud pulsars. The large, varied gamma-ray
pulsar sample constrains emission models. Fermiメs selection biases complement those of radio surveys, enhancing
comparisons with predicted population distributions
Low glutathione level favors formation of DNA adducts to 4-hydroxy-2(E)-nonenal, a major lipid peroxidation product
International audienc
Adducts of oxylipin electrophiles to glutathione reflect a 13 specificity of the downstream lipoxygenase pathway in the tobacco hypersensitive response
The response to reactive electrophile species (RES) is now considered as part of the plant response to pathogen and insect attacks. Thanks to a previously established high-performance liquid chromatography tandem mass spectrometry methodology, we have investigated the production of oxylipin RES adducts to glutathione (GSH) during the hypersensitive response (HR) of plants. We have observed that RES conjugation to GSH in tobacco (Nicotiana tabacum) leaves is facile and nonspecific. In cryptogein-elicited tobacco leaves, we show that the oxylipin RES adducts to GSH are produced in correlation with GSH consumption, increase in glutathione S-transferase activity, and the appearance of the cell death symptoms. In this model, the adducts arise mainly from the downstream 13 lipoxygenase (LOX) metabolism, although the induced 9 LOX pathway leads massively to the accumulation of upstream metabolites. The main adducts were obtained from 2-hexenal and 12-oxo-phytodienoic acid. They accumulate transiently as 1-hexanol-3-GSH, a reduced adduct, and 12-oxo-phytodienoic acid-GSH, respectively. RES conjugation does not initiate cell death but explains part of the GSH depletion that accompanies HR cell death. The nature of these GSH conjugates shows the key role played by the 13 LOX pathway in RES signaling in the tobacco HR