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https://www.readbyqxmd.com/read/28645064/heroin-and-saccharin-demand-and-preference-in-rats
#1
Lindsay P Schwartz, Jung S Kim, Alan Silberberg, David N Kearns
BACKGROUND: Several recent studies have investigated the choice between heroin and a non-drug alternative reinforcer in rats. A common finding in these studies is that there are large individual differences in preference, with some rats preferring heroin and some preferring the non-drug alternative. The primary goal of the present study was to determine whether individual differences in how heroin or saccharin is valued, based on demand analysis, predicts choice. METHODS: Rats lever-pressed for heroin infusions and saccharin reinforcers on fixed-ratio schedules...
June 13, 2017: Drug and Alcohol Dependence
https://www.readbyqxmd.com/read/28628816/are-calanco-landforms-similar-to-river-basins
#2
N A Caraballo-Arias, V Ferro
In the past badlands have been often considered as ideal field laboratories for studying landscape evolution because of their geometrical similarity to larger fluvial systems. For a given hydrological process, no scientific proof exists that badlands can be considered a model of river basin prototypes. In this paper the measurements carried out on 45 Sicilian calanchi, a type of badlands that appears as a small-scale hydrographic unit, are used to establish their morphological similarity with river systems whose data are available in the literature...
June 16, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28614590/chronic-ethanol-during-adolescence-impacts-corticolimbic-dendritic-spines-and-behavior
#3
Nicholas J Jury, Gabrielle A Pollack, Meredith J Ward, Jessica L Bezek, Alexandra J Ng, Courtney R Pinard, Hadley C Bergstrom, Andrew Holmes
BACKGROUND: Risk for alcohol use disorders (AUDs) in adulthood is linked to alcohol drinking during adolescence, but understanding of the neural and behavioral consequences of alcohol exposure during adolescence remains incomplete. Here, we examined the neurobehavioral impact of adolescent chronic intermittent EtOH (CIE) vapor exposure in mice. METHODS: C57BL/6J-background Thy1-EGFP mice were CIE-exposed during adolescence or adulthood and examined, as adults, for alterations in the density and morphology of dendritic spines in infralimbic (IL) cortex, prelimbic (PL) cortex, and basolateral amygdala (BLA)...
June 14, 2017: Alcoholism, Clinical and Experimental Research
https://www.readbyqxmd.com/read/28601602/abstinence-environment-contributes-to-age-differences-in-reinstatement-of-cocaine-seeking-between-adolescent-and-adult-male-rats
#4
Chen Li, Kyle J Frantz
RATIONALE: Extinction responding and cue-induced reinstatement of cocaine seeking after 60-days of forced abstinence are attenuated in male rats that self-administered cocaine during adolescence, compared with adults. Given that environmental enrichment during abstinence decreases reinstatement among adults, a possible explanation for attenuated reinstatement among adolescents is that standard pair-housing in prior studies creates a more stimulating environment for younger rats. OBJECTIVE: Therefore, we tested whether standard pair-housing is necessary for the attenuated reinstatement among adolescents by determining whether an impoverished environment during abstinence would increase reinstatement among adolescents, up to adult levels...
July 2017: Pharmacology, Biochemistry, and Behavior
https://www.readbyqxmd.com/read/28598863/characterization-of-the-discriminative-stimulus-effects-of-3-4-methylenedioxypyrovalerone-in-male-sprague-dawley-rats
#5
Michael D Berquist, Lisa E Baker
Recreational use of 3,4-methylenedioxypyrovalerone (MDPV) in the early 2000s prompted numerous scientific investigations of its behavioral and neurochemical effects. The purpose of this study was to further characterize the interoceptive stimulus effects of MDPV using a validated in-vivo drug-detection assay. Male Sprague-Dawley rats were trained to discriminate 0.3 mg/kg MDPV from saline under a fixed ratio 20 (FR 20) schedule of food reinforcement. After stimulus control was established with MDPV (∼35 training sessions), substitution tests were commenced with drugs from several chemical classes, including drugs with predominantly dopaminergic actions [MDPV, D-amphetamine, (+)-methamphetamine, (-)-cocaine], drugs with predominantly serotonergic actions [(+)-lysergic acid diethylamide, (+)-fenfluramine], and drugs with both serotonergic and dopaminergic actions (3,4-methylenedioxymethamphetamine, 4-methylmethcathinone)...
June 8, 2017: Behavioural Pharmacology
https://www.readbyqxmd.com/read/28589264/habitual-nicotine-seeking-in-rats-following-limited-training
#6
A Loughlin, D Funk, K Coen, A D Lê
RATIONALE AND OBJECTIVES: A potential reason that cigarette smoking can persist despite multiple quit attempts is that repeated voluntary nicotine intake may facilitate a transition from goal-directed to habitual behavioral control. Although accelerated habit formation for self-administered ethanol or cocaine has been previously demonstrated, this phenomenon has not been extensively studied with nicotine. We therefore examined the liability of nicotine self-administration to become habitual, while also examining that of orally consumed saccharin as an experimental control...
June 7, 2017: Psychopharmacology
https://www.readbyqxmd.com/read/28584928/effects-of-the-serotonin-2c-receptor-agonist-way163909-on-the-abuse-related-effects-and-mesolimbic-dopamine-neurochemistry-induced-by-abused-stimulants-in-rhesus-monkeys
#7
Laís F Berro, Maylen Perez Diaz, Eric Maltbie, Leonard L Howell
RATIONALE: Accumulating evidence shows that the serotonergic system plays a major role in psychostimulant abuse through its interactions with the dopaminergic system. Studies indicate that serotonin 5-HT2C receptors are one of the main classes of receptors involved in mediating the influence of serotonin in drug abuse. OBJECTIVE: The aim of the present study was to evaluate the effects of the selective serotonin 5-HT2C receptor agonist WAY163909 on the behavioral neuropharmacology of cocaine and methamphetamine in adult rhesus macaques...
June 5, 2017: Psychopharmacology
https://www.readbyqxmd.com/read/28581207/improving-postprandial-hyperglycemia-in-patients-with-type-2-diabetes-already-on-basal-insulin-therapy-a-review-of-current-strategies
#8
REVIEW
Guillermo E Umpierrez, Timothy S Bailey, Danielle Carcia, Charles Shaefer, Jay H Shubrook, Neil Skolnik
A large number of patients with type 2 diabetes (T2D) on basal insulin do not reach their glycosylated hemoglobin A1c (HbA1c) goals and require additional therapy to address postprandial hyperglycemia. Guidelines from expert bodies have outlined several approaches to accomplish post-prandial glucose (PPG) control, and recent literature suggests several more. This article provides strategies for primary care physicians caring for patients with T2D who do not achieve glycemic control with basal insulin alone...
June 5, 2017: Journal of Diabetes
https://www.readbyqxmd.com/read/28555315/differential-efficacies-of-the-nicotinic-%C3%AE-4%C3%AE-2-desensitizing-agents-in-reducing-nicotine-self-administration-in-female-rats
#9
Amir H Rezvani, Susan Slade, Corinne Wells, Venkata M Yenugonda, Yong Liu, Milton L Brown, Yingxian Xiao, Kenneth J Kellar, Edward D Levin
RATIONALE AND OBJECTIVES: Desensitization of neuronal nicotinic acetylcholine receptors holds promise as an effective treatment of tobacco addiction. Previously, we found that sazetidine-A (Saz-A), which selectively desensitizes α4β2 nicotinic receptors, significantly decreased intravenous (IV) nicotine self-administration (SA) in rats with an effective dose of 3 mg/kg in acute and repeated injection studies. We also found that chronic infusions of Saz-A at doses of 2 and 6 mg/kg/day significantly reduced nicotine SA in rats...
May 29, 2017: Psychopharmacology
https://www.readbyqxmd.com/read/28542848/change-of-transfusion-and-treatment-paradigm-in-major-trauma-patients
#10
P Stein, A Kaserer, K Sprengel, G A Wanner, B Seifert, O M Theusinger, D R Spahn
Trauma promotes trauma-induced coagulopathy, which requires urgent treatment with fixed-ratio transfusions of red blood cells, fresh frozen plasma and platelet concentrates, or goal-directed administration of coagulation factors based on viscoelastic testing. This retrospective observational study compared two time periods before (2005-2007) and after (2012-2014) the implementation of changes in trauma management protocols which included: use of goal-directed coagulation management; admission of patients to designated trauma centres; whole-body computed tomography scanning on admission; damage control surgery; permissive hypotension; restrictive fluid resuscitation; and administration of tranexamic acid...
May 23, 2017: Anaesthesia
https://www.readbyqxmd.com/read/28536867/suppressing-effect-of-cor659-on-alcohol-sucrose-and-chocolate-self-administration-in-rats-involvement-of-the-gabab-and-cannabinoid-cb1-receptors
#11
Paola Maccioni, Giancarlo Colombo, Irene Lorrai, Alessandro Zaru, Mauro A M Carai, Gian Luigi Gessa, Antonella Brizzi, Claudia Mugnaini, Federico Corelli
RATIONALE AND OBJECTIVES: COR659 [methyl2-(4-chlorophenylcarboxamido)-4-ethyl-5-methylthiophene-3-carboxylate] is a new, positive allosteric modulator (PAM) of the GABAB receptor. This study evaluated whether COR659 shared with previously tested GABAB PAMs the capacity to reduce alcohol self-administration in rats. RESULTS: Treatment with non-sedative doses of COR659 (2.5, 5, and 10 mg/kg; i.p.) suppressed lever-responding for alcohol (15% v/v) in Sardinian alcohol-preferring (sP) rats under the fixed ratio (FR) 4 (FR4) and progressive ratio (PR) schedules of reinforcement; COR659 was more potent and effective than the reference GABAB PAM, GS39783...
May 24, 2017: Psychopharmacology
https://www.readbyqxmd.com/read/28534263/n-acetylaspartylglutamate-inhibits-heroin-self-administration-and-heroin-seeking-behaviors-induced-by-cue-or-priming-in-rats
#12
Huaqiang Zhu, Miaojun Lai, Weisheng Chen, Disen Mei, Fuqiang Zhang, Huifeng Liu, Wenhua Zhou
Activation of presynaptic group II metabotropic glutamate receptors (mGluR2/3) inhibits drug reward and drug-seeking behavior, but the role of N-acetylaspartylglutamate (NAAG), an agonist of endogenous mGluR2/3, in heroin reward and heroin-seeking behavior remained unclear. Here, we aimed to explore the effects of exogenous NAAG on heroin self-administration and heroin-seeking behavior. First, rats were trained to self-administer heroin under a fixed ratio 1 (FR1) schedule for 10 days, then received NAAG (50 or 100 μg/10 μL in each nostril) in the absence or presence of LY341495 (1 mg/kg, i...
May 22, 2017: Neuroscience Bulletin
https://www.readbyqxmd.com/read/28516387/a-diffusion-weighted-imaging-informed-continuum-model-of-the-rabbit-triceps-surae-complex
#13
M Alipour, K Mithraratne, J Fernandez
The NZ white rabbit is the animal of choice for much experimental work due to its muscular frame and similar response to human diseases, and is one of the few mammals that have had their genome sequenced. However, continuum-level computational models of rabbit muscle detailing fibre architecture are limited in the literature, especially the triceps surae complex (gastrocnemius, plantaris and soleus), which has similar biomechanics and translatable findings to the human. This study presents a geometrical model of the rabbit triceps surae informed with diffusion-weighted imaging (DWI)-based fibres...
May 18, 2017: Biomechanics and Modeling in Mechanobiology
https://www.readbyqxmd.com/read/28507512/changes-in-dopamine-transmission-in-the-nucleus-accumbens-shell-and-core-during-ethanol-and-sucrose-self-administration
#14
Valentina Bassareo, Flavia Cucca, Roberto Frau, Gaetano Di Chiara
Ethanol, like other substances of abuse, preferentially increases dopamine (DA) transmission in the rat nucleus accumbens (NAc) following passive administration. It remains unclear, however, whether ethanol also increases NAc DA transmission following operant oral self-administration (SA). The NAc is made-up of a ventro-medial compartment, the shell and a dorso-lateral one, the core, where DA transmission responds differentially following exposure to drugs of abuse. Previous studies from our laboratory investigated changes in dialysate DA in the NAc shell and core of rats responding for sucrose pellets and for drugs of abuse...
2017: Frontiers in Behavioral Neuroscience
https://www.readbyqxmd.com/read/28505185/combined-treatment-of-miltefosine-and-paromomycin-delays-the-onset-of-experimental-drug-resistance-in-leishmania-infantum
#15
Sarah Hendrickx, Magali Van den Kerkhof, Dorien Mabille, Paul Cos, Peter Delputte, Louis Maes, Guy Caljon
BACKGROUND: Since miltefosine monotherapy against visceral leishmaniasis (VL) caused by Leishmania donovani has been discontinued in the Indian subcontinent due to an increase in the number of treatment failures, single dose liposomal amphotericin B is now advocated as a treatment option of choice. Paromomycin-miltefosine combination therapy can be used as substitute first-line treatment in regions without cold-chain potential. Previous laboratory studies in the closely related species Leishmania infantum have demonstrated that paromomycin monotherapy fairly rapidly selects for resistance producing a phenotype with increased fitness...
May 2017: PLoS Neglected Tropical Diseases
https://www.readbyqxmd.com/read/28451857/assessing-the-environmental-hazard-of-individual-and-combined-pharmaceuticals-acute-and-chronic-toxicity-of-fluoxetine-and-propranolol-in-the-crustacean-daphnia-magna
#16
Valentina Varano, Elena Fabbri, Andrea Pasteris
Pharmaceuticals are widespread emerging contaminants and, like all pollutants, are present in combination with others in the ecosystems. The aim of the present work was to evaluate the toxic response of the crustacean Daphnia magna exposed to individual and combined pharmaceuticals. Fluoxetine, a selective serotonin re-uptake inhibitor widely prescribed as antidepressant, and propranolol, a non-selective β-adrenergic receptor-blocking agent used to treat hypertension, were tested. Several experimental trials of an acute immobilization test and a chronic reproduction test were performed...
April 27, 2017: Ecotoxicology
https://www.readbyqxmd.com/read/28433597/prediction-of-toxicity-of-zinc-and-nickel-mixtures-to-artemia-sp-at-various-salinities-from-additivity-to-antagonism
#17
Évila Pinheiro Damasceno, Lívia Pitombeira de Figuerêdo, Marcionília Fernandes Pimentel, Susana Loureiro, Letícia Veras Costa-Lotufo
Few studies have examined the toxicity of metal mixtures to marine organisms exposed to different salinities. The aim of the present study was to investigate the acute toxicity of zinc and nickel exposures singly and in combination to Artemia sp. under salinities of 10, 17, and 35 psu. The mixture concentrations were determined according to individual toxic units (TUs) to follow a fixed ratio design. Zinc was more toxic than nickel, and both their individual toxicities were higher at lower salinities. These changes in toxicity can be attributed to the Biotic Ligand Model (BLM) rather than to metal speciation...
August 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/28432746/impact-of-baseline-hba1c-diabetes-duration-and-bmi-on-clinical-outcomes-in-the-lixilan-o-trial-testing-iglarlixi-insulin-glargine-lixisenatide-titratable-fixed-ratio-combination-versus-insulin-glargine-and-lixisenatide-monocomponents
#18
M J Davies, L A Leiter, B Guerci, G Grunberger, F J Ampudia-Blasco, C Yu, W Stager, E Niemoeller, E Souhami, J Rosenstock
To determine whether baseline characteristics impact clinical outcomes in the LixiLan-O trial (N = 1170), the efficacy and safety of iGlarLixi, a titratable fixed-ratio combination of insulin glargine 100 U (iGlar) and lixisenatide (Lixi) was compared with iGlar or Lixi alone in patients with uncontrolled type 2 diabetes mellitus (T2DM) on oral therapy. Subgroups according to baseline glycated haemoglobin (HbA1c; <8%, ≥8% [<64, ≥64 mmol/mol]); T2DM disease duration (<7, ≥7 years) and body mass index (BMI; <30, ≥30 kg/m(2) ) were investigated...
April 22, 2017: Diabetes, Obesity & Metabolism
https://www.readbyqxmd.com/read/28431947/a-bout-analysis-of-operant-response-disruption
#19
Ryan J Brackney, Timothy H C Cheung, Federico Sanabria
Operant behavior appears to be organized in bouts of responses, whose parameters are differentially sensitive to various manipulations. This study investigated potential differential effects of three forms of operant response disruption-extinction (EXT), non-contingent reinforcement (NCR), and prefeeding (PRE)-on response bouts. In Experiment 1, Wistar Kyoto rats (WKY) were trained on a tandem variable-time (VT) 120s fixed-ratio (FR) 5 schedule of reinforcement; after stability was established, their responding was disrupted for three sessions with one of the three disrupters (EXT, NCR, or PRE)...
April 19, 2017: Behavioural Processes
https://www.readbyqxmd.com/read/28429835/levodopa-prevents-the-reinstatement-of-cocaine-self-administration-in-rats-via-potentiation-of-dopamine-release-in-the-medial-prefrontal-cortex
#20
Silvia Antinori, Liana Fattore, Pierluigi Saba, Walter Fratta, Gian Luigi Gessa, Paola Devoto
Dopamine agonists have been proposed as therapeutic tools for cocaine addiction. We have recently demonstrated that indirect dopamine agonists, including levodopa (L-DOPA), markedly increase cocaine-induced dopamine release in the medial prefrontal cortex (mPFC) of rats leading to the suppression of cocaine-seeking behavior. This study was aimed to understand the behavioral and neurochemical effects of L-DOPA on cocaine-taking and cocaine-seeking in rats. After reaching a stable pattern of intravenous cocaine self-administration under a continuous fixed ratio (FR-1) schedule of reinforcement, male rats were treated with L-DOPA at different steps of the self-administration protocol...
April 21, 2017: Addiction Biology
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