The dopamine D2/D3 receptor agonist quinpirole increases checking-like behaviour in an operant observing response task with uncertain reinforcement: a novel possible model of OCD.

Excessive checking is a common, debilitating symptom of obsessive-compulsive disorder (OCD). In an established rodent model of OCD checking behaviour, quinpirole (dopamine D2/3-receptor agonist) increased checking in open-field tests, indicating dopaminergic modulation of checking-like behaviours. We designed a novel operant paradigm for rats (observing response task (ORT)) to further examine cognitive processes underpinning checking behaviour and clarify how and why checking develops. We investigated i) how quinpirole increases checking, ii) dependence of these effects on D2/3 receptor function (following treatment with D2/3 receptor antagonist sulpiride) and iii) effects of reward uncertainty. In the ORT, rats pressed an 'observing' lever for information about the location of an 'active' lever that provided food reinforcement. High- and low-checkers (defined from baseline observing) received quinpirole (0.5mg/kg, 10 treatments) or vehicle. Parametric task manipulations assessed observing/checking under increasing task demands relating to reinforcement uncertainty (variable response requirement and active-lever location switching). Treatment with sulpiride further probed the pharmacological basis of long-term behavioural changes. Quinpirole selectively increased checking, both functional observing lever presses (OLPs) and non-functional extra OLPs (EOLPs). The increase in OLPs and EOLPs was long-lasting, without further quinpirole administration. Quinpirole did not affect the immediate ability to use information from checking. Vehicle and quinpirole-treated rats (VEH and QNP respectively) were selectively sensitive to different forms of uncertainty. Sulpiride reduced non-functional EOLPs in QNP rats but had no effect on functional OLPs. These data have implications for treatment of compulsive checking in OCD, particularly for serotonin-reuptake-inhibitor treatment-refractory cases, where supplementation with dopamine receptor antagonists may be beneficial

Protocol for the PACE trial: A randomised controlled trial of adaptive pacing, cognitive behaviour therapy, and graded exercise as supplements to standardised specialist medical care versus standardised specialist medical care alone for patients with the chronic fatigue syndrome/myalgic encephalomyelitis or encephalopathy

<p>Abstract</p> <p>Background</p> <p>Chronic fatigue syndrome (CFS, also called myalgic encephalomyelitis/encephalopathy or ME) is a debilitating condition with no known cause or cure. Improvement may occur with medical care and additional therapies of pacing, cognitive behavioural therapy and graded exercise therapy. The latter two therapies have been found to be efficacious in small trials, but patient organisations' surveys have reported adverse effects. Although pacing has been advocated by patient organisations, it lacks empirical support. Specialist medical care is commonly provided but its efficacy when given alone is not established. This trial compares the efficacy of the additional therapies when added to specialist medical care against specialist medical care alone.</p> <p>Methods/Design</p> <p>600 patients, who meet operationalised diagnostic criteria for CFS, will be recruited from secondary care into a randomised trial of four treatments, stratified by current comorbid depressive episode and different CFS/ME criteria. The four treatments are standardised specialist medical care either given alone, or with adaptive pacing therapy or cognitive behaviour therapy or graded exercise therapy. Supplementary therapies will involve fourteen sessions over 23 weeks and a 'booster session' at 36 weeks. Outcome will be assessed at 12, 24, and 52 weeks after randomisation. Two primary outcomes of self-rated fatigue and physical function will assess differential effects of each treatment on these measures. Secondary outcomes include adverse events and reactions, subjective measures of symptoms, mood, sleep and function and objective measures of physical activity, fitness, cost-effectiveness and cost-utility. The primary analysis will be based on intention to treat and will use logistic regression models to compare treatments. Secondary outcomes will be analysed by repeated measures analysis of variance with a linear mixed model. All analyses will allow for stratification factors. Mediators and moderators will be explored using multiple linear and logistic regression techniques with interactive terms, with the sample split into two to allow validation of the initial models. Economic analyses will incorporate sensitivity measures.</p> <p>Discussion</p> <p>The results of the trial will provide information about the benefits and adverse effects of these treatments, their cost-effectiveness and cost-utility, the process of clinical improvement and the predictors of efficacy.</p

Hydrophilic interaction liquid chromatography (HILIC)—a powerful separation technique

Hydrophilic interaction liquid chromatography (HILIC) provides an alternative approach to effectively separate small polar compounds on polar stationary phases. The purpose of this work was to review the options for the characterization of HILIC stationary phases and their applications for separations of polar compounds in complex matrices. The characteristics of the hydrophilic stationary phase may affect and in some cases limit the choices of mobile phase composition, ion strength or buffer pH value available, since mechanisms other than hydrophilic partitioning could potentially occur. Enhancing our understanding of retention behavior in HILIC increases the scope of possible applications of liquid chromatography. One interesting option may also be to use HILIC in orthogonal and/or two-dimensional separations. Bioapplications of HILIC systems are also presented

Bequest motives and household money demand

Bequest Motives, Life-Cycle Motive, Money Demand, Panel Data, E41, D91,