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https://www.readbyqxmd.com/read/27896377/self-administration-and-behavioral-economics-of-second-generation-synthetic-cathinones-in-male-rats
#1
S L Huskinson, J E Naylor, E A Townsend, J K Rowlett, B E Blough, K B Freeman
RATIONALE: Synthetic cathinones have become increasingly available as drugs of abuse. Distribution of these drugs is made possible by altering the chemical structures of prohibited cathinones and marketing them under misleading labels. Very little is known about the relative reinforcing effectiveness of new synthetic cathinones relative to known drugs of abuse. OBJECTIVE: We examined self-administration of three second-generation synthetic cathinones: alpha-pyrrolidinopentiophenone (alpha-PVP), 4-methyl-N-ethylcathinone (4-MEC), and 4-methyl-alpha-pyrrolidinopropiophenone (4-MePPP) relative to methamphetamine...
November 28, 2016: Psychopharmacology
https://www.readbyqxmd.com/read/27888373/combined-toxic-effect-of-airborne-heavy-metals-on-human-lung-cell-line-a549
#2
Yeowool Choi, Kihong Park, Injeong Kim, Sang D Kim
Many studies have demonstrated that heavy metals existing as a mixture in the atmospheric environment cause adverse effects on human health and are important key factors of cytotoxicity; however, little investigation has been conducted on a toxicological study of a metal mixture from atmospheric fine particulate matter. The objective of this study was to predict the combined effects of heavy metals in aerosol by using in vitro human cells and obtain a suitable mixture toxicity model. Arsenic, nickel, and lead were selected for mixtures exposed to A549 human lung cancer cells...
November 25, 2016: Environmental Geochemistry and Health
https://www.readbyqxmd.com/read/27886524/effects-of-ethanol-on-cocaine-self-administration-in-monkeys-responding-under-a-second-order-schedule-of-reinforcement
#3
William S John, Michael A Nader
BACKGROUND: Concurrent alcohol use among cocaine abusers is common but the behavioral variables that promote co-abuse are not well understood. The present study examined the effects of intragastric (i.g.) ethanol (EtOH) administration in monkeys responding under a schedule of cocaine reinforcement in which extensive drug seeking was maintained by conditioned stimuli. METHODS: Four adult male cynomolgus monkeys (Macaca fascicularis) were trained to respond under a second-order fixed-interval (FI) 600s (fixed-ratio (FR) 30:S) schedule of cocaine (0...
November 10, 2016: Drug and Alcohol Dependence
https://www.readbyqxmd.com/read/27869181/functional-states-of-rat-cortical-circuits-during-the-unpredictable-availability-of-a-reward-related-cue
#4
Iván Fernández-Lamo, Raudel Sánchez-Campusano, Agnès Gruart, José M Delgado-García M
Proper performance of acquired abilities can be disturbed by the unexpected occurrence of external changes. Rats trained with an operant conditioning task (to press a lever in order to obtain a food pellet) using a fixed-ratio (1:1) schedule were subsequently placed in a Skinner box in which the lever could be removed randomly. Field postsynaptic potentials (fPSPs) were chronically evoked in perforant pathway-hippocampal CA1 (PP-CA1), CA1-subiculum (CA1-SUB), CA1-medial prefrontal cortex (CA1-mPFC), mPFC-nucleus accumbens (mPFC-NAc), and mPFC-basolateral amygdala (mPFC-BLA) synapses during lever IN and lever OUT situations...
November 21, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27864048/aversive-properties-of-negative-incentive-shifts-in-fischer-344-and-lewis-rats
#5
Adam Brewer, Patrick Johnson, Jeff Stein, Michael Schlund, Dean C Williams
Research on incentive contrast highlights that reward value is not absolute but rather is based upon comparisons we make to rewards we have received and expect to receive. Both human and nonhuman studies on incentive contrast show that shifting from a larger more-valued reward to a smaller less-valued reward is associated with long periods of nonresponding - a negative contrast effect. In this investigation, we used two different genetic rat strains, Fischer 344 and Lewis rats that putatively differ in their sensitivity to aversive stimulation, to assess the aversive properties of large-to-small reward shifts (negative incentive shifts)...
November 15, 2016: Behavioural Brain Research
https://www.readbyqxmd.com/read/27860181/methamphetamine-self-administration-reduces-alcohol-consumption-and-preference-in-alcohol-preferring-p-rats
#6
Madeline C Winkler, Emilee M Greager, Jacob Stafford, Ryan K Bachtell
Subclinical levels of polysubstance use are a prevalent and understudied phenomenon. Alcohol is a substance commonly co-used with other substances of other drug classes. These studies sought to determine the consumption effects of combining alcohol drinking and methamphetamine (MA) self-administration. Male alcohol-preferring P rats had continuous access to a two-bottle alcohol drinking procedure in the home cage. Control rats remained alcohol naïve. Rats were also surgically implanted with intra-jugular catheters and trained to self-administer saline (control) or MA in daily 2-hour sessions...
November 16, 2016: Addiction Biology
https://www.readbyqxmd.com/read/27817804/a-comparison-of-five-surveys-that-identify-individuals-at-risk-for-airflow-obstruction-and-chronic-obstructive-pulmonary-disease
#7
Folarin Sogbetun, William L Eschenbacher, Jeffrey A Welge, Ralph J Panos
BACKGROUND: The predictive characteristics of different screening surveys for the recognition of individuals at risk for airflow obstruction (AFO) have not been evaluated simultaneously in the same population. PURPOSE: To compare five AFO/COPD screening questionnaires. METHODS: 383 individuals completed the Veterans Airflow Obstruction Screening Questionnaire, Personal Level Screener for COPD (VAFOSQ), the 11-Q COPD Screening Questionnaire (11-Q), the COPD Population Screener (COPD-PS) and the Lung Function Questionnaire (LFQ) and performed spirometry...
November 2016: Respiratory Medicine
https://www.readbyqxmd.com/read/27817750/l-tetrahydropalmatine-reduces-nicotine-self-administration-and-reinstatement-in-rats
#8
Shamia L Faison, Charles W Schindler, Steven R Goldberg, Jia Bei Wang
BACKGROUND: The negative consequences of nicotine use are well known and documented, however, abstaining from nicotine use and achieving abstinence poses a major challenge for the majority of nicotine users trying to quit. l-Tetrahydropalmatine (l-THP), a compound extracted from the Chinese herb Corydalis, displayed utility in the treatment of cocaine and heroin addiction via reduction of drug-intake and relapse. The present study examined the effects of l-THP on abuse-related effects of nicotine...
November 7, 2016: BMC Pharmacology & Toxicology
https://www.readbyqxmd.com/read/27730727/impairment-of-opiate-mediated-behaviors-by-the-selective-trpv1-antagonist-sb366791
#9
Shi-Xun Ma, Seung-Hwan Kwon, Jee-Yeon Seo, Ji-Young Hwang, Sa-Ik Hong, Hyoung-Chun Kim, Seok-Yong Lee, Choon-Gon Jang
Transient receptor potential vanilloid type 1 (TRPV1), the archetypal member of the vanilloid TRP family, was initially identified as the receptor for capsaicin, the pungent ingredient in hot chili peppers. We previously demonstrated that TRPV1 in the dorsal striatum significantly contributes to morphine reward by using the conditioned place preference paradigm in mice; however, it is unknown whether TRPV1 has the same effect in other reward models. In this study, we investigated the role of TRPV1 in morphine reward by using a self-administration paradigm in rats...
October 11, 2016: Addiction Biology
https://www.readbyqxmd.com/read/27723981/self-delivery-nanoparticles-of-amphiphilic-methotrexate-gemcitabine-prodrug-for-synergistic-combination-chemotherapy-via-effect-of-deoxyribonucleotide-pools
#10
Yao Wang, Ping Huang, Minxi Hu, Wei Huang, Xinyuan Zhu, Deyue Yan
The distinct and complementary biochemical mechanisms of folic acid analog methotrexate (MTX) and cytidine analog gemcitabine (GEM) make their synergistic combination effectively. Unfortunately, such a combination faces severe pharmacokinetic problems and several transportation barriers. To overcome these problems, a new strategy of amphiphilic small molecule prodrug (ASMP) is developed to improve their synergistic combination effect. The ASMP was prepared by the amidation of the hydrophilic GEM with the hydrophobic MTX at a fixed ratio...
October 10, 2016: Bioconjugate Chemistry
https://www.readbyqxmd.com/read/27720801/acute-bouts-of-wheel-running-decrease-cocaine-self-administration-influence-of-exercise-output
#11
Mark A Smith, Gaylen E Fronk, Huailin Zhang, Charlotte P Magee, Andrea M Robinson
Exercise is associated with lower rates of drug use in human populations and decreases drug self-administration in laboratory animals. Most of the existing literature examining the link between exercise and drug use has focused on chronic, long-term exercise, and very few studies have examined the link between exercise output (i.e., amount of exercise) and drug self-administration. The purpose of this study was to examine the effects of acute bouts of exercise on cocaine self-administration, and to determine whether these effects were dependent on exercise output and the time interval between exercise and drug self-administration...
October 5, 2016: Pharmacology, Biochemistry, and Behavior
https://www.readbyqxmd.com/read/27718204/analysis-of-the-innate-response-to-adjuvants-characterization-of-the-draining-lymph-node-by-fluorescence-activated-cell-sorting
#12
Anthony L Desbien
A clear index for a response to adjuvants is a change in the cellular composition of lymph nodes draining the site of adjuvant injection (Didierlaurent et al., J Immunol 183:6186-6197, 2009; Caproni et al., J Immunol 188:3088-98, 2012; Desbien et al., Eur J Immunol 1-11, 2014). During the steady state, lymph nodes (LNs) are composed of a fixed ratio of innate and adaptive cells awaiting activation signals from tissue draining lymph. Upon exposure to innate stimulants, lymph nodes undergo dramatic changes. The most apparent change to the lymph node is an increase in size...
2017: Methods in Molecular Biology
https://www.readbyqxmd.com/read/27701442/a-longitudinal-operant-assessment-of-cognitive-and-behavioural-changes-in-the-hdhq111-mouse-model-of-huntington-s-disease
#13
Emma Yhnell, Stephen B Dunnett, Simon P Brooks
Huntington's disease (HD) is characterised by motor symptoms which are often preceded by cognitive and behavioural changes, that can significantly contribute to disease burden for people living with HD. Numerous knock-in mouse models of HD are currently available for scientific research. However, before their use, they must be behaviourally characterised to determine their suitability in recapitulating the symptoms of the human condition. Thus, we sought to longitudinally characterise the nature, severity and time course of cognitive and behavioural changes observed in HdhQ111 heterozygous knock-in mice...
2016: PloS One
https://www.readbyqxmd.com/read/27695921/sex-differences-and-the-role-of-dopamine-receptors-in-the-reward-enhancing-effects-of-nicotine-and-bupropion
#14
Scott T Barrett, Trevor N Geary, Amy N Steiner, Rick A Bevins
RATIONALE: Nicotine and bupropion have been demonstrated to enhance the value of other reinforcers, and this may partially account for nicotine reward and dependence. Evidence suggests that the sexes differ in their sensitivity to the primary and secondary reinforcing effects of nicotine and nicotine-associated stimuli. Whether the sexes also differ in sensitivity to the reward-enhancing effects of nicotine (and bupropion) is yet unclear. OBJECTIVES: The present study evaluated potential sex differences in the enhancement effects of nicotine and bupropion using a reinforcer demand approach...
October 1, 2016: Psychopharmacology
https://www.readbyqxmd.com/read/27685834/behavioral-history-of-withdrawal-influences-regulation-of-cocaine-seeking-by-glutamate-re-uptake
#15
Luyi Zhou, Haley Andersen, Adrian C Arreola, Jill R Turner, Pavel I Ortinski
Withdrawal from cocaine regulates expression of distinct glutamate re-uptake transporters in the nucleus accumbens (NAc). In this study, we examined the cumulative effect of glutamate re-uptake by multiple excitatory amino acid transporters (EAATs) on drug-seeking at two different stages of withdrawal from self-administered cocaine. Rats were trained on fixed ratio 1 (FR1), progressing to FR5 schedule of reinforcement. After one day of withdrawal, microinfusion of a broad non-transportable EAAT antagonist, DL-threo-beta-benzyloxyaspartate (DL-TBOA), into the NAc shell dose-dependently attenuated self-administration of cocaine...
2016: PloS One
https://www.readbyqxmd.com/read/27684728/should-the-diagnosis-of-copd-be-based-on-a-single-spirometry-test
#16
Tjard R Schermer, Bas Robberts, Alan J Crockett, Bart P Thoonen, Annelies Lucas, Joke Grootens, Ivo J Smeele, Cindy Thamrin, Helen K Reddel
Clinical guidelines indicate that a chronic obstructive pulmonary disease (COPD) diagnosis is made from a single spirometry test. However, long-term stability of diagnosis based on forced expiratory volume in 1 s over forced vital capacity (FEV1/FVC) ratio has not been reported. In primary care subjects at risk for COPD, we investigated shifts in diagnostic category (obstructed/non-obstructed). The data were from symptomatic 40+ years (ex-)smokers referred for diagnostic spirometry, with three spirometry tests, each 12±2 months apart...
September 29, 2016: NPJ Primary Care Respiratory Medicine
https://www.readbyqxmd.com/read/27680584/further-evaluation-of-the-use-of-multiple-schedules-for-behavior-maintained-by-negative-reinforcement
#17
Claudia Campos, Yanerys Leon, Andressa Sleiman, Beatriz Urcuyo
One potential limitation of functional communication training (FCT) is that after the functional communication response (FCR) is taught, the response may be emitted at high rates or inappropriate times. Thus, schedule thinning is often necessary. Previous research has demonstrated that multiple schedules can facilitate schedule thinning by establishing discriminative control of the communication response while maintaining low rates of problem behavior. To date, most applied research evaluating the clinical utility of multiple schedules has done so in the context of behavior maintained by positive reinforcement (e...
September 27, 2016: Behavior Modification
https://www.readbyqxmd.com/read/27650977/efficacy-and-safety-of-lixilan-a-titratable-fixed-ratio-combination-of-insulin-glargine-plus-lixisenatide-in-type-2-diabetes-inadequately-controlled-on-basal-insulin-and-metformin-the-lixilan-l-randomized-trial
#18
Vanita R Aroda, Julio Rosenstock, Carol Wysham, Jeffrey Unger, Diego Bellido, Guillermo González-Gálvez, Akane Takami, Hailing Guo, Elisabeth Niemoeller, Elisabeth Souhami, Richard M Bergenstal
OBJECTIVE: This study was conducted to demonstrate the efficacy and safety of LixiLan (iGlarLixi), a novel, titratable, fixed-ratio combination of insulin glargine (iGlar) (100 units) and lixisenatide, compared with iGlar in patients with type 2 diabetes inadequately controlled on basal insulin with or without up to two oral glucose-lowering agents. RESEARCH DESIGN AND METHODS: After a 6-week run-in when iGlar was introduced and/or further titrated, and oral antidiabetic drugs other than metformin were stopped, 736 basal insulin-treated patients (mean diabetes duration 12 years, BMI 31 kg/m(2)) were randomized 1:1 to open-label, once-daily iGlarLixi or iGlar, both titrated to fasting plasma glucose <100 mg/dL (<5...
September 20, 2016: Diabetes Care
https://www.readbyqxmd.com/read/27650954/effects-of-lorcaserin-on-cocaine-and-methamphetamine-self-administration-and-reinstatement-of-extinguished-responding-in-rhesus-monkeys
#19
Lisa R Gerak, Gregory T Collins, Charles P France
Stimulant abuse is a serious public health issue for which there is no effective pharmacotherapy. The serotonin2C (5-HT2C) receptor agonist lorcaserin decreases some abuse-related effects of cocaine in monkeys and might be useful for treating stimulant abuse. The current study investigated the effectiveness of lorcaserin to reduce self-administration of either cocaine or methamphetamine and cocaine-induced reinstatement of extinguished responding. Four rhesus monkeys responded under a progressive ratio (PR) schedule in which the response requirement increased after each cocaine infusion (32-320 μg/kg/infusion)...
September 20, 2016: Journal of Pharmacology and Experimental Therapeutics
https://www.readbyqxmd.com/read/27640338/characterization-of-the-discriminative-stimulus-effects-of-lorcaserin-in-rats
#20
Katherine M Serafine, Kenner C Rice, Charles P France
Lorcaserin is approved by the Food and Drug Administration for treating obesity and is under consideration for treating substance use disorders; it has agonist properties at serotonin (5-HT)2C receptors and might also have agonist properties at other 5-HT receptor subtypes. This study used drug discrimination to investigate the mechanism(s) of action of lorcaserin. Male Sprague-Dawley rats discriminated 0.56 mg/kg i.p. lorcaserin from saline while responding under a fixed-ratio 5 schedule for food. Lorcaserin (0...
September 2016: Journal of the Experimental Analysis of Behavior
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