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We present the first X-ray detection of the very young pulsar PSR J1357-6429 (characteristic age of 7.3 kyr) using data from the XMM-Newtonand Chandrasatellites. We find that the spectrum is well described by a power-law plus blackbody model, with photon index $\Gamma=1.4$and blackbody temperature $k_{\rm B}T=160$eV. For the estimated distance of 2.5 kpc, this corresponds to a 2–10 keV luminosity of ~1.2 $\times$1032erg s-1, thus the fraction of the spin-down energy channeled by PSR J1357-6429 into X-ray emission is one of the lowest observed. The Chandradata confirm the positional coincidence with the radio pulsar and allow to set an upper limit of 3 $\times$1031erg s-1on the 2–10 keV luminosity of a compact pulsar wind nebula. We do not detect any pulsed emission from the source and determine an upper limit of 30% for the modulation amplitude of the X-ray emission at the radio frequency of the pulsar.

Aims.4U 1954+319 was discovered 25 years ago, but only recently has a clear picture of its nature begun to emerge. We present for the first time a broad-band spectrum of the source and a detailed timing study using more than one year of monitoring data.

A deep (100 ks) XMM-Newton observation of Geminga has shown two faint tails of diffuse X-ray emission, extending for ~$2'$behind the pulsar, well aligned with the proper motion (PM) direction. We report here on a recent ~20 ks Chandra observation, which unveils a new structure, ~$25''$long and ~$5''$thick, starting at the pulsar position and perfectly aligned with the PM direction, with a surface brightness ~40 times higher than that of the XMM Tails. The Chandra comet-like feature has a remarkably hard spectrum (photon index ~$0.9{-}1.4$) and a luminosity of ~$5.5\times10^{28}$erg s-1, comparable to the energetics of the larger XMM one. Geminga is thus the first neutron star to show a clear X-ray evidence of a large-scale, outer bow-shock as well as a short, inner cometary trail.

Despite it being well known that anaphylaxis is a severe life-threatening reaction requiring prompt management and treatment, this entity is still under-recognized and not correctly managed, above all in children. The aim of this study was to analyze the most frequent features of anaphylaxis in a pediatric population (n=65 patients) and to identify factors predicting more severe reactions. Among the 70 recorded episodes, food was the main culprit of anaphylaxis, and patients with a positive history for allergic asthma had more severe episodes (P=0.008). A self-injectable adrenaline was used only in 2 of the 70 episodes and none of the 50 episodes managed in the Emergency Department was treated with intramuscular adrenaline. Only 10/65 patients (15%) had a prescription for an auto-injector prior to the first episode of anaphylaxis. The retrospective analysis of the risk factors potentially requiring an epinephrine auto-injector prescription before the first anaphylactic episode, showed that of the 55 patients without prescription, at least 10 (18%) should have been provided with a device, according to the most recent guidelines. In conclusion, notwithstanding intramuscular adrenaline being the first-line treatment of anaphylaxis, many episodes are still undertreated and the risk of anaphylaxis is still underestimated. More efforts should be made to promote the correct management of anaphylaxis among both healthcare-providers and patients.

To assess incidence and predictors of acute symptomatic seizures in a prospective cohort of patients with first stroke.