A Planet in a 0.6-AU Orbit Around the K0 Giant HD 102272

We report the discovery of one or more planet-mass companions to the K0-giant HD 102272 with the Hobby-Eberly Telescope. In the absence of any correlation of the observed periodicities with the standard indicators of stellar activity, the observed radial velocity variations are most plausibly explained in terms of a Keplerian motion of at least one planet-mass body around the star. With the estimated stellar mass of 1.9M$_\odot$, the minimum mass of the confirmed planet is 5.9M$_J$. The planet's orbit is characterized by a small but nonzero eccentricity of $e$=0.05 and the semi-major axis of 0.61 AU, which makes it the most compact one discovered so far around GK-giants. This detection adds to the existing evidence that, as predicted by theory, the minimum size of planetary orbits around intermediate-mass giants is affected by both planet formation processes and stellar evolution. The currently available evidence for another planet around HD 102272 is insufficient to obtain an unambiguous two-orbit solution.Comment: 10 pages, 5 figure

The Palomar Testbed Interferometer Calibrator Catalog

The Palomar Testbed Interferometer (PTI) archive of observations between 1998 and 2005 is examined for objects appropriate for calibration of optical long-baseline interferometer observations - stars that are predictably point-like and single. Approximately 1,400 nights of data on 1,800 objects were examined for this investigation. We compare those observations to an intensively studied object that is a suitable calibrator, HD217014, and statistically compare each candidate calibrator to that object by computing both a Mahalanobis distance and a Principal Component Analysis. Our hypothesis is that the frequency distribution of visibility data associated with calibrator stars differs from non-calibrator stars such as binary stars. Spectroscopic binaries resolved by PTI, objects known to be unsuitable for calibrator use, are similarly tested to establish detection limits of this approach. From this investigation, we find more than 350 observed stars suitable for use as calibrators (with an additional $\approx 140$ being rejected), corresponding to $\gtrsim 95$ sky coverage for PTI. This approach is noteworthy in that it rigorously establishes calibration sources through a traceable, empirical methodology, leveraging the predictions of spectral energy distribution modeling but also verifying it with the rich body of PTI's on-sky observations.Comment: 100 pages, 7 figures, 7 tables; to appear in the May 2008ApJS, v176n

The MINDVIEW project: First results

[EN] We present the first results of the MINDVIEW project. An innovative imaging system for the human brain examination, allowing simultaneous acquisition of PET/MRI images, has been designed and constructed. It consists of a high sensitivity and high resolution PET scanner integrated in a novel, head-dedicated, radio frequency coil for a 3T MRI scanner. Preliminary measurements from the PET scanner show sensitivity 3 times higher than state-of-the-art PET systems that will allow safe repeated studies on the same patient. The achieved spatial resolution, close to 1 mm, will enable differentiation of relevant brain structures for schizophrenia. A cost-effective and simple method of radiopharmaceutical production from C-11-carbon monoxide and a mini-clean room has been demonstrated. It has been shown that C-11-raclopride has higher binding potential in a new VAAT null mutant mouse model of schizophrenia compared to wild type control animals. A significant reduction in TSPO binding has been found in gray matter in a small sample of drug-naive, first episode psychosis patients, suggesting a reduced number or an altered function of immune cells in brain at early stage schizophrenia. (c) 2018 Elsevier Masson SAS. All rights reserved.This project is funded by EU grant FP7-HEALTH-F2-2013-603002.Benlloch Baviera, JM.; González Martínez, AJ.; Pani, R.; Preziosi, E.; Jackson, C.; Murphy, J.; Barbera Ballester, J.... (2018). The MINDVIEW project: First results. European Psychiatry. 50:21-27. https://doi.org/10.1016/j.eurpsy.2018.01.002S212750Gonzalez, A. J., Gonzalez-Montoro, A., Aguilar, A., Conde, P., Canizares, G., Hernandez, L., … Benlloch, J. M. (2016). A brain PET insert MR compatible: Final design and first results. 2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD). doi:10.1109/nssmic.2016.8069619Dahl, K., Schou, M., Ulin, J., Sjöberg, C.-O., Farde, L., & Halldin, C. (2015). 11C-carbonylation reactions using gas–liquid segmented microfluidics. RSC Advances, 5(108), 88886-88889. doi:10.1039/c5ra20646d[26] Långström B and Sjöberg CO, System for controlling environment in reaction box, From PCT Int. Appl. (2013), WO 2013103312 A1 20130711.Autret, A., Bert, J., Strauss, O., & Visvikis, D. (2012). Projector with realistic detector scatter modelling for PET list-mode reconstruction. 2012 IEEE Nuclear Science Symposium and Medical Imaging Conference Record (NSS/MIC). doi:10.1109/nssmic.2012.6551759[10] Young JW Head and Face Antropometry of Adult U.S. Citizens, Civil Aeromedical Institute, Federal Aviation Administration, U.S. Department of Transportation, Report number DOT/FAA/AM-93/10, July 1993.Braff, D. L. (1990). Sensorimotor Gating and Schizophrenia. Archives of General Psychiatry, 47(2), 181. doi:10.1001/archpsyc.1990.01810140081011Preziosi, E., Sánchez, S., González, A. J., Pani, R., Borrazzo, C., Bettiol, M., … Benlloch, J. M. (2016). Performance study of a PET scanner based on monolithic scintillators for different DoI-dependent methods. Journal of Instrumentation, 11(12), C12076-C12076. doi:10.1088/1748-0221/11/12/c12076Howes, O., McCutcheon, R., & Stone, J. (2015). Glutamate and dopamine in schizophrenia: An update for the 21st century. Journal of Psychopharmacology, 29(2), 97-115. doi:10.1177/0269881114563634Moliner, L., Correcher, C., González, A. J., Conde, P., Hernández, L., Orero, A., … Benlloch, J. M. (2013). Implementation and analysis of list mode algorithm using tubes of response on a dedicated brain and breast PET. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 702, 129-132. doi:10.1016/j.nima.2012.08.029Zelano, J., Mikulovic, S., Patra, K., Kühnemund, M., Larhammar, M., Emilsson, L., … Kullander, K. (2013). The synaptic protein encoded by the gene Slc10A4 suppresses epileptiform activity and regulates sensitivity to cholinergic chemoconvulsants. Experimental Neurology, 239, 73-81. doi:10.1016/j.expneurol.2012.09.006Antich, P., Malakhov, N., Parkey, R., Slavin, N., & Tsyganov, E. (2002). 3D position readout from thick scintillators. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 480(2-3), 782-787. doi:10.1016/s0168-9002(01)01214-1Gonzalez-Montoro, A., Benlloch, J. M., Gonzalez, A. J., Aguilar, A., Canizares, G., Conde, P., … Sanchez, F. (2017). Performance Study of a Large Monolithic LYSO PET Detector With Accurate Photon DOI Using Retroreflector Layers. IEEE Transactions on Radiation and Plasma Medical Sciences, 1(3), 229-237. doi:10.1109/trpms.2017.2692819Rahman, O., Takano, A., Amini, N., Dahl, K., Kanegawa, N., Långström, B., … Halldin, C. (2015). Synthesis of ([11C]carbonyl)raclopride and a comparison with ([11C]methyl)raclopride in a monkey PET study. Nuclear Medicine and Biology, 42(11), 893-898. doi:10.1016/j.nucmedbio.2015.07.003Howes, O. D., Kambeitz, J., Kim, E., Stahl, D., Slifstein, M., Abi-Dargham, A., & Kapur, S. (2012). The Nature of Dopamine Dysfunction in Schizophrenia and What This Means for Treatment. Archives of General Psychiatry, 69(8). doi:10.1001/archgenpsychiatry.2012.169Ling, T., Lewellen, T. K., & Miyaoka, R. S. (2007). Depth of interaction decoding of a continuous crystal detector module. Physics in Medicine and Biology, 52(8), 2213-2228. doi:10.1088/0031-9155/52/8/012González, A. J., Majewski, S., Sánchez, F., Aussenhofer, S., Aguilar, A., Conde, P., … Benlloch, J. M. (2016). The MINDView brain PET detector, feasibility study based on SiPM arrays. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 818, 82-90. doi:10.1016/j.nima.2016.02.046Wong, D. F., Waterhouse, R., Kuwabara, H., Kim, J., Brasic, J. R., Chamroonrat, W., … Mozley, P. D. (2013). 18F-FPEB, a PET Radiopharmaceutical for Quantifying Metabotropic Glutamate 5 Receptors: A First-in-Human Study of Radiochemical Safety, Biokinetics, and Radiation Dosimetry. Journal of Nuclear Medicine, 54(3), 388-396. doi:10.2967/jnumed.112.107995Jackson, C., O’Neill, K., Wall, L., & McGarvey, B. (2014). High-volume silicon photomultiplier production, performance, and reliability. Optical Engineering, 53(8), 081909. doi:10.1117/1.oe.53.8.081909Rahman, O., Långström, B., & Halldin, C. (2016). Alkyl Iodides and [11 C]CO in Nickel-Mediated Cross-Coupling Reactions: Successful Use of Alkyl Electrophiles containing a β Hydrogen Atom in Metal-Mediated [11 C]Carbonylation. ChemistrySelect, 1(10), 2498-2501. doi:10.1002/slct.201600643Sullivan, J. M., Lim, K., Labaree, D., Lin, S., McCarthy, T. J., Seibyl, J. P., … Morris, E. D. (2012). Kinetic Analysis of the Metabotropic Glutamate Subtype 5 Tracer [18F]FPEB in Bolus and Bolus-Plus-Constant-Infusion Studies in Humans. Journal of Cerebral Blood Flow & Metabolism, 33(4), 532-541. doi:10.1038/jcbfm.2012.195Levin, C. S. (2003). Detector design issues for compact nuclear emission cameras dedicated to breast imaging. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 497(1), 60-74. doi:10.1016/s0168-9002(02)01893-4Larhammar, M., Patra, K., Blunder, M., Emilsson, L., Peuckert, C., Arvidsson, E., … Kullander, K. (2015). SLC10A4 Is a Vesicular Amine-Associated Transporter Modulating Dopamine Homeostasis. Biological Psychiatry, 77(6), 526-536. doi:10.1016/j.biopsych.2014.07.017Kaul, M., Surti, S., & Karp, J. S. (2013). Combining Surface Treatments With Shallow Slots to Improve the Spatial Resolution Performance of Continuous, Thick LYSO Detectors for PET. IEEE Transactions on Nuclear Science, 60(1), 44-52. doi:10.1109/tns.2013.2240315Bleich, A., Brown, S.-L., Kahn, R., & van Praag, H. M. (1988). The Role of Serotonin in Schizophrenia. Schizophrenia Bulletin, 14(2), 297-315. doi:10.1093/schbul/14.2.29

Naltrexone modulates dopamine release following chronic, but not acute amphetamine administration : a translational study

The opioid antagonist naltrexone has been shown to attenuate the subjective effects of amphetamine. However, the mechanisms behind this modulatory effect are currently unknown. We hypothesized that naltrexone would diminish the striatal dopamine release induced by amphetamine, which is considered an important mechanism behind many of its stimulant properties. We used positron emission tomography and the dopamine D2-receptor radioligand [C-11]raclopride in healthy subjects to study the dopaminergic effects of an amphetamine injection after pretreatment with naltrexone or placebo. In a rat model, we used microdialysis to study the modulatory effects of naltrexone on dopamine levels after acute and chronic amphetamine exposure. In healthy humans, naltrexone attenuated the subjective effects of amphetamine, confirming our previous results. Amphetamine produced a significant reduction in striatal radioligand binding, indicating increased levels of endogenous dopamine. However, there was no statistically significant effect of naltrexone on dopamine release. The same pattern was observed in rats, where an acute injection of amphetamine caused a significant rise in striatal dopamine levels, with no effect of naltrexone pretreatment. However, in a chronic model, naltrexone significantly attenuated the dopamine release caused by reinstatement of amphetamine. Collectively, these data suggest that the opioid system becomes engaged during the more chronic phase of drug use, evidenced by the modulatory effect of naltrexone on dopamine release following chronic amphetamine administration. The importance of opioid-dopamine interactions in the reinforcing and addictive effects of amphetamine is highlighted by the present findings and may help to facilitate medication development in the field of stimulant dependence

The Effects of Naltrexone on Subjective Response to Methamphetamine in a Clinical Sample: a Double-Blind, Placebo-Controlled Laboratory Study

Methamphetamine (MA) use disorder is a serious psychiatric condition for which there are no FDA-approved medications. Naltrexone (NTX) is an opioid receptor antagonist with demonstrated efficacy, albeit moderate, for the treatment of alcoholism and opioid dependence. Preclinical and clinical studies suggest that NTX may be useful for the treatment of MA use disorder. To inform treatment development, we conducted a double-blind, randomized, crossover, placebo-controlled human laboratory study of NTX. Non-treatment-seeking individuals meeting DSM-IV criteria for MA abuse or dependence (n=30) completed two separate 5-day inpatient stays. During each admission, participants completed testing sessions comprised of MA cue-reactivity and intravenous MA administration (30 mg) after receiving oral NTX (50 mg) or placebo for 4 days. This study tested the hypotheses that NTX would (a) attenuate cue-induced MA craving, and (b) reduce subjective responses to MA administration. Results largely supported the study hypotheses such that (a) NTX significantly blunted cue-induced craving for MA and (b) attenuated several of the hedonic subjective effects of MA, including craving, during controlled MA administration and as compared with placebo. NTX decreased overall subjective ratings of ‘crave drug,' ‘stimulated,' and ‘would like drug access,' decreased the the post-MA administration timecourse of ‘anxious' and increased ratings of ‘bad drug effects,' as compared with placebo. These findings support a potential mechanism of action by showing that NTX reduced cue-induced craving and subjective responses to MA. This is consistent with positive treatment studies of NTX for amphetamine dependence, as well as ongoing clinical trials for MA