This article examines the responses of ministers facing high levels of blame in the press after serious failures in the public exam system for school‐leavers in Scotland in 2000 and England in 2002. It develops a method for systematic analysis and comparison of the behaviour of officeholders facing blame, tests the hypothesis that ministers will accept personal culpability only after other ways of handling blame have been exhausted and uses time series intervention models to show how one can estimate the impact of strategies on the next day's blame level. The basic sequencing hypothesis is partially upheld by the observed behaviour in these cases, though many other kinds of blame responses do not display a clear sequence. The intervention analysis also raises questions about the claimed effectiveness of presentational strategies for managing blame.
Changes in metabolites detected by proton magnetic resonance spectroscopy ((1)H MRS) of the brain have been demonstrated in Alzheimer's disease. Our objectives were, first, longitudinally to measure absolute concentrations of metabolites in both hippocampi, the sites of early Alzheimer's disease, in patients with clinical Alzheimer's disease and controls; secondly, to separate the relative contribution of atrophy and metabolite concentration change to overall signal change; and, thirdly, to determine whether metabolite concentrations in the hippocampus relate to cognitive scores. (1)H MR spectra were acquired from a single voxel (12 x 15 x 25 mm(3) = 4.5 ml) aligned to the long axis of each hippocampus in nine probable or possible Alzheimer's disease subjects diagnosed according to the National Institute of Neurologic and Cognitive Disorders and Stroke (NINCDS) compared with 14 age-matched NINCDS-negative Alzheimer's disease controls. Metabolite concentrations were corrected for the amount of CSF present in the voxel. Hippocampal volumes were measured at the same time. The same protocol was repeated approximately 1 year later. We found that atrophy-corrected hippocampal N-acetylaspartate (NAA) concentration was lower in cognitively impaired subjects compared with controls. This was significant for the left hippocampus (baseline 87% of control, P = 0.013; and at 1 year 76% of control, P = 0.020). Hippocampal volumes also differed significantly between the groups, and decreased significantly over 1 year in the Alzheimer's disease group (12%, P = 0.017). The decrease in [NAA] over 1 year was not significant in either group. Discriminant analysis revealed that the best classification of subjects was by including both left NAA concentration and left hippocampal volume. myo-Inositol signals from these small voxels had poor signal-to-noise and demonstrated no significant changes. We conclude that (1)HMRS-detectable metabolites can be quantified from the hippocampi of cognitively impaired individuals, and that hippocampal [NAA] is significantly reduced in Alzheimer's disease, in excess of atrophy. In our cohort, the differences were more significant for the left hippocampus.
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • Drugs that inhibit the human cardiac delayed rectifier potassium current may lead to prolongation of the cardiac QT interval and are associated with a fatal, polymorphic, ventricular tachycardia known as torsades de pointes. • Lamotrigine is indicated in the treatment of epilepsy and the prevention of mood episodes in patients with bipolar disorder. • Lamotrigine inhibits the human cardiac delayed rectifier potassium current in vitro, and it has been hypothesized that QT prolongation may contribute to the risk of sudden unexpected death in epilepsy patients. WHAT THIS STUDY ADDS • This is the first reported thorough QT/QTc study with lamotrigine conducted to International Conference on Harmonization guidelines. • The mean QTc interval was not prolonged by lamotrigine in healthy subjects, as assessed by the standard heart rate correction methods (Fridericia's and Bazett's). • The in vitro inhibition of the delayed rectifier potassium current does not translate into an effect on QT in man. AIM To characterize the effects of lamotrigine on QT interval in healthy subjects. METHODS Healthy subjects received a single oral dose of moxifloxacin (400 mg) or placebo in crossover design, followed by a dose‐escalating regimen of lamotrigine (n = 76) over a 77‐day period, or matched placebo (n = 76). Blood samples were taken for determination of moxifloxacin and lamotrigine concentrations and digital 12‐lead ECGs were recorded. The relationships between individual QT values and respective individual moxifloxacin or lamotrigine concentrations were explored using population pharmacokinetic–pharmacodynamic (PK–PD) modelling. RESULTS Moxifloxacin was associated with a maximum mean increase from baseline in QTcF of 14.81 ms [90% confidence interval (CI) 13.50, 16.11] 2.5 h after dosing. Steady‐state exposure to lamotrigine (50, 150 or 200 mg b.d.) was not associated with an increase in QTc interval. Small reductions in QTcF (maximum mean difference from placebo −7.48 ms, 90% CI −10.49, −4.46) and small increases in heart rate (maximum mean difference from placebo 5.94 bpm, 90% CI 3.81, 8.06) were observed with lamotrigine 200 mg b.d. vs. placebo. No effect of lamotrigine on QRS duration or blood pressure was observed. No outliers with QTcF > 450 ms, or with an increase from baseline of >60 ms were observed in the lamotrigine group. PK–PD modelling indicated statistically significant decreases in individually corrected QT intervals for lamotrigine and statistically significant increases in individually corrected QT intervals for moxifloxacin over the concentration ranges studied. CONCLUSIONS Therapeutic doses of lamotrigine (50–200 mg b.d.) were not associated with QT prolongation in healthy subjects.
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