26 research outputs found
Scientific Performance of the ISDC Quick Look Analysis
The INTEGRAL Science Data Centre (ISDC) routinely monitors the Near Real Time
data (NRT) from the INTEGRAL satellite. A first scientific analysis is made in
order to check for the detection of new, transient or highly variable sources
in the data. Of primary importance for this work is the Interactive Quick Look
Analysis (IQLA), which produces JEM-X and ISGRI images and monitors them for
interesting astrophysical eventsComment: 4 pages, 3 figures. Proceedings of 5th INTEGRAL Workshop: The
INTEGRAL Universe, Munich, 16-20 February 2004. Accepted for publication in
European Space Agency Special Publication 552. See paper for institute
affiliation
Breakthrough invasive fungal disease in patients receiving posaconazole primary prophylaxis: a 4-year study
AbstractPosaconazole (PSC) is currently recommended as primary prophylaxis in neutropenic patients with acute myeloid leukaemia (AML) and in allogenic haematopoietic stem cell transplantation (AHSCT) recipients with graft-versus-host disease (GVHD). Studies focusing on breakthrough invasive fungal disease (IFD) upon PSC prophylaxis show disparate results. In order to evaluate the incidence of IFD in patients on PSC prophylaxis and identify IFD risk factors, we carried out a retrospective study of all consecutive patients on PP from January 2007 to December 2010 in our hospital. Breakthrough IFDs were identified from the database of the central pharmacy and the French administrative database (PMSI), registering final medical diagnoses of hospitalized patients. Medical data were reviewed to study proven or probable IFD, according to EORTC/MSG definition. PSC plasma concentrations (PPC) were also retrieved. Poisson models were used for statistical analysis. Two hundred and seventy-nine patients received PSC prophylaxis for a median duration of 1.4 months (range 0.2–17.9). Proven (n = 6) or probable (n = 3) IFDs were diagnosed in nine cases (3.2%). IFD incidence rate per 100 person-month was 1.65 (95% CI, 0.79–2.97). IFDs were candidaemia (Candida glabrata, n = 2), pulmonary invasive aspergillosis (n = 3), disseminated fusariosis (n = 2) and pulmonary mucormycosis (n = 2). Seven deaths were reported, directly related to IFD in three patients (33.3%). First dosage of PPC under 0.3 mg/L was the single significant risk factor for IFD (RR, 7.77; 95% CI, 1.30–46.5; p 0.025). Breakthrough IFD in patients receiving PSC prophylaxis is rare but associated with a poor outcome. Low PSC plasma concentrations are associated with an increased risk of IFD
In flight calibration of the ISGRI camera
ISGRI, the IBIS low energy camera (15 keV - 1 MeV) on board INTEGRAL, is the
first large CdTe gamma-ray imager in orbit. We present here an overview of the
ISGRI in-flight calibrations performed during the first months after launch. We
discuss the stability of the camera as well as the CdTe pixels response under
cosmic radiation. The energy calibra tions were done using lead and tungsten
fluorescence lines and the calibration unit. Thermal effects
and charge correction algorithm are discussed, and the resulting energy
resolution is presented. The ISGRI background spatial and spectral
non-uniformity is also described, and some image correction results are
presented
The INTEGRAL/IBIS Scientific Data Analysis
The gamma-ray astronomical observatory INTEGRAL, succesfully launched on 17th
October 2002, carries two large gamma-ray telescopes. One of them is the
coded-mask imaging gamma-ray telescope onboard the INTEGRAL satellite (IBIS)
which provides high-resolution (~ 12') sky images of 29deg x 29deg in the
energy range from 15 keV to 10 MeV with typical on-axis sensitivity of ~ 1
mCrab at 100 keV (3 sigma, 10E6 s exposure). We report here the general
description of the IBIS coded-mask imaging system and of the standard IBIS
science data analysis procedures. These procedures reconstruct, clean and
combine IBIS sky images providing at the same time detection, identification
and preliminary analysis of point-like sources present in the field. Spectral
extraction has also been implemented and is based on simultaneous fitting of
source and background shadowgram models to detector images. The procedures are
illustrated using some of the IBIS data collected during the inflight
calibrations and present performance is discussed. The analysis programs
described here have been integrated as instrument specific software in the
Integral Science Data Center (ISDC) analysis software packages currently used
for the Quick Look, Standard and Off-line Scientific Analysis.Comment: 7 pages, 13 figures (6 color), accepted for publication in A&A Lett
(INTEGRAL special issue). Full resulution color figures can be found in the
printed version of the paper (see
http://www.edpsciences.org/articles/aa/abs/2003/43/contents/contents.html
ISGRI: the INTEGRAL Soft Gamma-Ray Imager
For the first time in the history of high energy astronomy, a large CdTe
gamma-ray camera is operating in space. ISGRI is the low-energy camera of the
IBIS telescope on board the INTEGRAL satellite. This paper details its design
and its in-flight behavior and performances. Having a sensitive area of 2621
cm with a spatial resolution of 4.6 mm, a low threshold around 12 keV and
an energy resolution of 8% at 60 keV, ISGRI shows absolutely no signs of
degradation after 9 months in orbit. All aspects of its in-flight behavior and
scientific performance are fully nominal, and in particular the observed
background level confirms the expected sensitivity of 1 milliCrab for a 10s
observation.Comment: INTEGRAL A&A special issu
INTEGRAL: In flight behavior of ISGRI and SPI
International audienceThe payload of INTEGRAL, the space gamma-ray observatory launched in October 2002, features two gamma-ray telescopes that take advantage of the semiconductor technologies. The spectrometer SPI, is equipped with 19 high-purity germanium detectors cooled at 85 K. We will report on the SPI in-flight background, performance, the detector evolution and the annealings performed every 6 months. The INTEGRAL Soft Gamma-Ray Imager (ISGRI) is the low-energy camera of the IBIS telescope. It is the first large camera equipped with CdTe detectors. We will present some system aspects, in particular the noisy pixel handling and will report on its in-flight background, performance and their evolution
Toward the cottonization of hemp fibers by steam explosion – Part 1: defibration and morphological characterization
Cytochrome 2B6 polymorphism and efavirenz-induced central nervous system symptoms : a substudy of the ANRS ALIZE trial
International audienceOBJECTIVES:Single nucleotide polymorphisms in the cytochrome P450 (CYP) 2B6 gene have been associated with high interindividual variation in efavirenz pharmacokinetics. However, clinical data on the relationship of CYP2B6 polymorphisms with the occurrence of efavirenz-induced central nervous system (CNS) symptoms are limited.METHODS:We analysed four polymorphisms in the CYP2B6 (516 G>T), CYP3A5 (6986 A>G) and ATP-binding cassette, sub-family B, member 1 (ABCB1) (2677 G>T/A and 3435 C>T) genes in HIV-infected adults virologically suppressed on a protease inhibitor-based regimen who switched to a regimen containing emtricitabine, didanosine and efavirenz in the setting of the ANRS ALIZE trial. Kaplan-Meier methods and Cox regression analysis were used to investigate their association with efavirenz plasma levels and CNS events up to 48 months after switching.RESULTS:In total, 191 patients with a median age of 41 years, who were 87% male and 85% Caucasian, were enrolled in the study. Variant allelic frequencies were 0.49, 0.93, 0.59 and 0.63 for CYP2B6 516, CYP3A5 392, ABCB1 2677 and ABCB1 3435, respectively. The median efavirenz plasma concentration (MEPC) was 2.2 mg/L [interquartile range (IQR) 1.7-2.8 mg/L] and was significantly higher in patients with the deficient CYP2B6 516T. Overall, 242 CNS events were reported in 104 individuals (54%). No correlation was found between MEPC and CNS events. The occurrence of a first CNS event was lower in patients with the CYP2B6 516 G/G genotype vs. CYP2B6 516 T genotypes [50% (IQR: 40-60%) vs. 66% (IQR: 56-75%), respectively; P = 0.02]. In an adjusted Cox regression model, there was a tendency towards a higher risk of a first CNS event among carriers of the variant CYP2B6 516 T allele (relative risk 1.4 [95% CI, 0.99-2.1]; P?=?.06), compared with noncarriers.CONCLUSIONS:The deficient CYP2B6 516 T allele is associated with higher efavirenz plasma drug levels and more frequent CNS-related symptoms