Background: Gamma-hydroxybutyric acid (GHB) is a drug of abuse associated with increased emergency room attendances, due to GHB-induced comas. Withdrawal from GHB often increases social anxiety and ...is linked to alterations in emotion processing. However, little is known about the effects of GHB-use and GHB-induced comas on affect regulation in humans. Objectives: We aimed to assess the effect of GHB-use and GHB-induced comas on the affective network. Method: We recruited 27 GHB users with ≥4 GHB-induced comas (GHB-Coma), 27 GHB users without a GHB-induced coma (GHB-NoComa), and 27 polydrug users who never used GHB (No-GHB). Participants completed self-report questionnaires assessing negative affect (depression, anxiety and stress) and performed an emotional face matching task during functional magnetic resonance imaging to probe activity of the amygdala and the hippocampus. Results: The GHB-Coma group reported higher levels of depression, anxiety, and stress; showed decreased activity of the hippocampus; and increased functional connectivity of the left hippocampus with the left fusiform gyrus and a cluster on the left temporal-parietal-occipital junction, when compared with the 2 other groups. The GHB-NoComa group showed decreased functional connectivity of the left hippocampus with the amygdala in comparison with the No-GHB group. Conclusions: GHB-use but in particular GHB-induced comas, are associated with altered emotion identification and hippocampal functioning. Awareness campaigns are required to raise consciousness about the adverse effects of GHB-induced comas on affect regulation, despite the absence of subjective side effects.
Gamma-hydroxybutyric acid (GHB) is a recreational drug associated with increasing numbers of GHB-dependent patients and emergency attendances often related to GHB-induced comas. Working memory (WM) ...deficits have been reported in association with GHB use, and animal studies have shown that GHB induces oxidative stress in vulnerable WM-related brain areas such as the dorsolateral prefrontal cortex (DLPFC). However, the effects of chronic GHB use and multiple GHB-induced comas on WM-related brain function in humans remains unknown.
We recruited 27 GHB users with ≥4 GHB-induced comas (GHB-Coma), 27 GHB users who never experienced GHB-induced coma (GHB-NoComa), and 27 polydrug users who never used GHB (No-GHB). Participants performed an n-back WM task during functional magnetic resonance imaging (fMRI) to probe DLPFC functioning.
The GHB-Coma group had lower premorbid IQ (p = .006) than the GHB-NoComa group despite comparable age and education level. There were also group differences in the use of other drugs than GHB. Therefore, all group comparisons were adjusted for IQ and drug use other than GHB. Compared with the GHB-NoComa and the No-GHB groups, the GHB-Coma group showed increased activity in the right DLPFC (pSVC = 0.028) and increased functional connectivity of the right DLPFC with a cluster comprising the left anterior cingulate and medial frontal gyrus (pFWE = 0.003). No significant fMRI differences were observed between the GHB-NoComa and No-GHB groups. Due to technical problems, no behavioural data were collected.
These results suggest that multiple GHB-induced comas, but not GHB-use per se, are associated with alterations in WM-related brain function. Public awareness campaigns are required to minimize the potential adverse effects induced by GHB recreational use, and especially GHB-induced comas, even if no immediate side effects are experienced.
•It appears that not GHB use per se, but multiple GHB-induced comas are associated with an alteration of the working memory network in regular GHB-users.•A Multiple GHB-induced comas are associated with hyperactivation of the right dorsal-lateral pre-frontal cortex (DLPFC).•Multiple GHB-induced comas are associated with increased DLPFC functional connectivity with the left anterior cingulate and medial frontal gyrus.
We present the first determination of the Galactic polarized emission at 353 GHz by Archeops. The data were taken during the Arctic night of February 7, 2002 after the balloon-borne instrument was ...launched by CNES from the Swedish Esrange base near Kiruna. In addition to the 143 GHz and 217 GHz frequency bands dedicated to CMB studies, Archeops had one 545 GHz and six 353 GHz bolometers mounted in three polarization-sensitive pairs that were used for Galactic foreground studies. We present maps of the I, Q, U Stokes parameters over 17% of the sky and with a 13 arcmin resolution at 353 GHz (850 mu m). They show a significant Galactic large scale polarized emission coherent on the longitude ranges 100, 120 and 180, 200 deg. with a degree of polarization at the level of 4-5%, in agreement with expectations from starlight polarization measurements. Some regions in the Galactic plane (Gem OB1, Cassiopeia) show an even stronger degree of polarization in the range 10-20%. These findings provide strong evidence for a powerful grain alignment mechanism throughout the interstellar medium and a coherent magnetic field coplanar to the Galactic plane. This magnetic field pervades even some dense clouds. Extrapolated to high Galactic latitude, these results indicate that interstellar dust polarized emission is the major foreground for PLANCK-HFI CMB polarization measurements.
The CaLIPSO project focuses on the development of an innovative energetic-photon detector. The detector uses a "heavy" organometallic liquid: the TriMethyl Bismuth (TMBi), 82% by weight of Bismuth. ...TMBi efficiently converts through the photo-electric effect photons of energies below 1 MeV. The ionisation signal and light produced in the liquid are both detected. Beyond the measurement of gamma photon energies, this detector will allow locating photon interactions in the detector in three dimensions down to 1 mm 3 and a sub nanosecond timing accuracy. All these desirable properties can be obtained simultaneously with liquid TMBi detector.
We analyze the cosmological constraints that Archeops (Benoît et al. 2003) places on adiabatic cold dark matter models with passive power-law initial fluctuations. Because its angular power spectrum ...has small bins in $\ell$ and large $\ell$ coverage down to COBE scales, Archeops provides a precise determination of the first acoustic peak in terms of position at multipole $l_{\rm peak}=220\pm 6$, height and width. An analysis of Archeops data in combination with other CMB datasets constrains the baryon content of the Universe, $\Omega_{\rm b}h^2= 0.022^{+0.003}_{-0.004}$, compatible with Big-Bang nucleosynthesis and with a similar accuracy. Using cosmological priors obtained from recent non–CMB data leads to yet tighter constraints on the total density, e.g. $\Omega_{\rm tot}=1.00^{+0.03}_{-0.02}$ using the HST determination of the Hubble constant. An excellent absolute calibration consistency is found between Archeops and other CMB experiments, as well as with the previously quoted best fit model. The spectral index n is measured to be $1.04^{+0.10}_{-0.12}$ when the optical depth to reionization, τ, is allowed to vary as a free parameter, and $0.96^{+0.03}_{-0.04}$ when τ is fixed to zero, both in good agreement with inflation.
Background: There is evidence indicating that serotonin uptake and density of 5-HT
2A receptors are altered in brain regions of depressed suicide victims and in platelets of depressed suicidal ...subjects. The present investigation tested the hypothesis that these changes in the serotonergic system in depressed suicide victims are trait rather than state markers and associated with a polymorphism in respective candidate genes.
Methods: Two polymorphic variants (102T/C polymorphism and His
452Tyr functional polymorphism) of the 5-HT
2A receptor gene and a functional polymorphism in the 5′ regulatory region of the 5-HT transporter gene, have been determined in genomic DNA obtained from postmortem brain samples of 24 depressed suicide victims and 31 control subjects of the same ethnic background. In a subset of subjects, density (B
max) of 5-HT uptake sites (labeled with
3H-paroxetine) and of 5-HT
2A receptors (labeled with
3H-ketanserin) was also determined in prefrontal cortex samples.
Results: The major finding of this study was a significantly higher frequency of the 5-HT transporter gene long (L) allele (χ
2 = 3.9, df = 1; p = .048) in depressed suicides. No significant differences between suicides and controls were observed for the 102T/C polymorphism and His
452Tyr polymorphism of 5-HT
2A receptor gene. The density of
3H-paroxetine binding sites tended to be higher in subjects expressing the short (S) allele of 5-HT transporter gene. Furthermore, there was a significant difference in serotonin transporter binding sites between the genotype S/S and combined genotypes S/L and L/L.
Conclusions: Our finding provides the first evidence suggesting that a functional polymorphism in the regulatory region of serotonin transporter gene may be associated with suicide in depressed subjects.
We present a determination by the Archeops experiment of the angular power spectrum of the cosmic microwave background anisotropy in 16 bins over the multipole range $\ell=15{-}350$. Archeops was ...conceived as a precursor of the Planck HFI instrument by using the same optical design and the same technology for the detectors and their cooling. Archeops is a balloon–borne instrument consisting of a 1.5 m aperture diameter telescope and an array of 21 photometers maintained at $\sim 100$ mK that are operating in 4 frequency bands centered at 143, 217, 353 and 545 GHz. The data were taken during the Arctic night of February 7, 2002 after the instrument was launched by CNES from Esrange base (Sweden). The entire data cover ~30% of the sky. This first analysis was obtained with a small subset of the dataset using the most sensitive photometer in each CMB band (143 and 217 GHz) and 12.6% of the sky at galactic latitudes above 30 degrees where the foreground contamination is measured to be negligible. The large sky coverage and medium resolution (better than 15 arcmin) provide for the first time a high signal-to-noise ratio determination of the power spectrum over angular scales that include both the first acoustic peak and scales probed by COBE/DMR. With a binning of $\Delta \ell=7$ to 25 the error bars are dominated by sample variance for $\ell$ below 200. A companion paper details the cosmological implications.
A major goal of CMB experiments is to obtain highly sensitive CMB maps in order to extract Spherical Harmonic Power Spectrum (SHPS) and cosmological parameters with unprecedented accuracy. We present ...a new map-making code (Mirage) based on a two-phase iterative algorithm, involving low frequency drift treatment, Butterworth high-pass filtering, and conjugate gradient method. This work was strongly motivated by Archeops CMB experiment data analysis, which we believe is a good test bench for future Planck Surveyor data analysis. Mirage was designed to be used for Planck data processing with a minimum amount of effort. A strong feature of Mirage is that it handles experimental problems in data, such as holes in the data stream, bright sources, and galaxy side effects, without jeopardising speed. The other advantage is its processing speed that allows Monte Carlo simulations of Archeops data processing to be run overnight on a single processor workstation. Algorithms are explained and systematic effects on SHPS investigated on various simulated data, including typical Archeops observational systematics. The code is now available at http://www-dapnia.cea.fr/Telechargement/tel_mirage.php
Aims.Archeops is a balloon-borne experiment inspired by the Planck satellite and its high frequency instrument (HFI). It is designed to measure the cosmic microwave background (CMB) temperature ...anisotropies at high angular resolution (~12 arcmin) over a large fraction of the sky (around 30%) at 143, 217, 353, and 545 GHz. The Archeops 353 GHz channel consists of three pairs of polarized sensitive bolometers designed to detect the polarized diffuse emission of Galactic dust. Methods.In this paper we present an update of the instrumental setup, as well as the flight performance for the last Archeops flight campaign (February 2002 from Kiruna, Sweden). We also describe the processing and analysis of the Archeops time-ordered data for that campaign, which led to measurement of the CMB anisotropy power spectrum in the multipole range $\ell$ = 10-700 and to the first measurements of both the polarized emission of dust at large angular scales and its power spectra in the multipole range $\ell$ = 3-70 Results.We present maps covering approximately 30% of the sky. These maps contain Galactic emission, including the Galactic plane, in the four Archeops channels at 143, 217, 353, and 545 GHz and CMB anisotropies at 143 and 217 GHz. These are one of the first sub-degree-resolution maps in the millimeter and submillimeter ranges of the large angular-scale diffuse Galactic dust emission and CMB temperature anisotropies, respectively.
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