Enhanced sensitivity of postsynaptic serotonin-1A receptors in rats and mice with high trait aggression

Individual differences in aggressive behaviour have been linked to variability in central serotonergic activity, both in humans and animals. A previous experiment in mice, selectively bred for high or low levels of aggression, showed an up-regulation of postsynaptic serotonin-1A (5-HT1A) receptors, both in receptor binding and in mRNA levels, in the aggressive line. The aim of this experiment was to study whether similar differences in 5-HT1A receptors exist in individuals from a random-bred rat strain, varying in aggressiveness. In addition, because little is known about the functional consequences of these receptor differences, a response mediated via postsynaptic 5-HT1A receptors (i.e., hypothermia) was studied both in the selection lines of mice and in the randomly bred rats. The difference in receptor binding, as demonstrated in mice previously, could not be shown in rats. However, both in rats and mice, the hypothermic response to the 5-HT1A agonist alnespirone was larger in aggressive individuals. So, in the rat strain as well as in the mouse lines, there is, to a greater or lesser extent, an enhanced sensitivity of postsynaptic 5-HT1A receptors in aggressive individuals. This could be a compensatory up-regulation induced by a lower basal 5-HT neurotransmission, which is in agreement with the serotonin deficiency hypothesis of aggression.

Misdirection and guidance of regenerating motor axons after experimental nerve injury and repair

Misdirection of regenerating motor axons is one of the factors that can explain the disappointing recovery of function often observed after nerve injury and repair. In the first part of this thesis we quantified misdirection of motor axon regeneration after different types of nerve injury and repair in the rat sciatic nerve model, and we investigated the impact on functional recovery with ankle motion analysis. In the second part of this thesis we investigated two tools to guide regenerating motor axons in vivo: mechanical guidance with multichannel nerve tubes and biological guidance with gene therapy.Sundt fellowship (Mayo Clinic), Leids Universitair Fonds (LUF), Janneke Fruin-Helb beurs, Stichting Fundatie van de Vrijvrouwe van Renswoude te ‘s Gravenhage, Stichting Mitialto, Stichting Dr. Hendrik Muller’s Vaderlandsch Fonds, Lustra and Jo Keur FondsUBL - phd migration 201

The ATESP Radio Survey II. The Source Catalogue

This paper is part of a series reporting the results of the Australia Telescope ESO Slice Project (ATESP) radio survey obtained at 1400 MHz with the Australia Telescope Compact Array (ATCA) over the region covered by the ESO Slice Project (ESP) galaxy redshift survey. The survey consists of 16 radio mosaics with ~8"x14" resolution and uniform sensitivity (1sigma noise level ~79 microJy) over the whole area of the ESP redshift survey (~26 sq. degrees at decl. -40 degr). Here we present the catalogue derived from the ATESP survey. We detected 2960 distinct radio sources down to a flux density limit of ~0.5 mJy (6sigma), 1402 being sub-mJy sources. We describe in detail the procedure followed for the source extraction and parameterization. The internal accuracy of the source parameters was tested with Monte Carlo simulations and possible systematic effects (e.g. bandwidth smearing) have been quantified.Comment: 14 pages, 14 Postscript figures, Accepted for publication in A&A Suppl. Corrected typos and added Journal Referenc

The ATESP 5 GHz radio survey. II. Physical properties of the faint radio population

One of the most debated issues about sub-mJy radio sources, which are responsible for the steepening of the 1.4 GHz source counts, is the origin of their radio emission. Particularly interesting is the possibility of combining radio spectral index information with other observational properties to assess whether the sources are triggered by star formation or nuclear activity. The aim of this work is to study the optical and near infrared properties of a complete sample of 131 radio sources with S>0.4 mJy, observed at both 1.4 and 5 GHz as part of the ATESP radio survey. We use deep multi-colour (UBVRIJK) images, mostly taken in the framework of the ESO Deep Public Survey, to optically identify and derive photometric redshifts for the ATESP radio sources. Deep optical coverage and extensive colour information are available for 3/4 of the region covered by the radio sample. Typical depths of the images are U~25, B~26, V~25.4, R~25.5, I~24.3, 19.5<K_s<20.2, J<22.2. Optical/near infrared counterparts are found for ~78% (66/85) of the radio sources in the region covered by the deep multi-colour imaging, and for 56 of these reliable estimates of the redshift and type are derived. We find that many of the sources with flat radio spectra are characterised by high radio-to-optical ratios (R>1000), typical of classical powerful radio galaxies and quasars. Flat-spectrum sources with low R values are preferentially identified with early type galaxies, where the radio emission is most probably triggered by low-luminosity active galactic nuclei. Considering both early type galaxies and quasars as sources with an active nucleus, such sources largely dominate our sample (78%). Flat-spectrum sources associated with early type galaxies are quite compact (d<10-30 kpc), suggesting core-dominated radio emission.Comment: 15 pages, 13 figures, accepted for pubblication in A&

Enhanced detection of atrial tachyarrhythmias with pacing devices by using more accurate atrial sensing

Publisher Copyright: © 2021, The Author(s).Purpose: Cardiac pacing devices can detect and monitor atrial tachyarrhythmias (ATA) which increase the risk of thromboembolic complications. The aim of this study was to compare (1) two different atrial leads and (2) standard and optimized settings to detect ATA and reject far-field R-wave signal (FFRW). Methods: This was a prospective, randomized multi-center trial comparing St. Jude Medical OptiSense lead (tip-to-ring spacing 1.1 mm) and Tendril lead (tip-to-ring spacing 10.0 mm), having programmed atrial sensitivity at 0.2 mV and post-ventricular atrial blanking at 60 ms. We measured intra-atrial amplitudes of FFRW, intrinsic atrial signals, the amount of FFRW oversensing, and other inappropriate mode switching. Results: One hundred and ten patients were enrolled. The mean amplitude of sensed and paced FFRW bipolar signal was 0.13 mV vs. 0.21 mV (p < 0.001) and 0.13 mV vs. 0.26 mV (p < 0.001) with OptiSense and Tendril lead, respectively. The mean amplitude of the atrial bipolar signal was 2.84 mV with OptiSense and 3.48 mV with Tendril lead, p = 0.014. With the optimized settings with OptiSense lead, one patient out of 20 (5%) had FFRW oversensing, none had undersensing of ATAs due to 2:1-blanking of atrial depolarizations, and the concordance of the ATAs by Holter and pacemaker memory was high (Spearman’s rank correlation coefficient = 0.90). In the Tendril group, 12 out of 25 patients (48%) had oversensing and 4 had atrial undersensing (p < 0.001). Conclusions: The technique with an atrial lead with short tip-to-ring spacing combined with optimized pacemaker programming resulted in reliable and accurate atrial arrhythmia detection. Trial registration: ClinicalTrials.gov number NCT01074749.Peer reviewe

Peroxisomes in intestinal and gallbladder epithelial cells of the stickleback, Gasterosteus aculeatus L. (Teleostei)

The occurrence of microbodies in the epithelial cells of the intestine and gallbladder of the stickleback, Gasterosteus aculeatus L., is described. In the intestine the organelles are predominantly located in the apical and perinuclear zone of the cells and may contain small crystalline cores. In gallbladder epithelial cells the microbodies are distributed randomly. The latter organdies are characterized by the presence of large crystalloids. Cytochemical and biochemical experiments show that catalase and D-amino acid oxidase are main matrix components of the microbodies in both the intestinal and gallbladder epithelia. These organelles therefore are considered peroxisomes. In addition, in intestinal mucosa but not in gallbladder epithelium a low activity of palmitoyl CoA oxidase was detected biochemically. Urate oxidase and L-α hydroxy acid oxidase activities could not be demonstrated.

The nature of close companions of the BL Lac Objects 1ES 0502+675 and 1ES 1440+122

We report on deep radio images and optical spectroscopy of two BL Lac objects that have very close compact companions. The two targets, 1ES 0502+675 and 1ES 1440+122, were selected from the HST imaging survey of 110 BL Lacs as candidates for possible gravitational lensing. The new observations clearly demonstrate that the companion objects are not secondary images of the active nuclei but, in spite of the relatively low chance projection probability, foreground Galactic stars. Gravitational lensing appears to be unimportant to the BL Lac phenomenon. We discuss the radio properties of the BL Lac objects in the context of standard beaming models, and show they are as expected for beamed FRI radio galaxies.Comment: 13 pages, 5 figures, ApJ in pres