Lithium concentrations in plasma of lithium-treated psychiatric patients in the Netherlands:commentary on Cusin et al.

Seasonal variations in 68 psychiatric patients receiving prophylactic lithium treatment in the Netherlands between 1974 and 1994 were analyzed and compared with findings from Italy. Although lithium doses remained stable, there was a significant change in plasma levels of lithium, with values in spring and summer tending to exceed those in autumn and winter. These findings are similar to those reported in Italy, although the maximal seasonal change was approximately 5% in the Netherlands compared with approximately 10% in Italy. The difference could reflect the hotter summer climate in Italy, associated with increased perspiration. Future Studies should measure perspiration levels directly. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved

Edge detection versus densitometry in the quantitative assessment of stenosis phantoms: an in vivo comparison in procine coronary arteries

The aim of this study was the in vivo validation and comparison of the geometric and densitometric technique of a computer-assisted automatic quantitative angiographic system (CAAS system). In six Landrace Yorkshire pigs (45 to 55 kg), precision-drilled phantoms with a circular lumen of 0.5, 0.7, 1.0, 1.4, and 1.9 mm were percutaneously introduced into the left anterior descending or left circumflex coronary artery. Twenty-eight coronary angiograms obtained with the phantom in a wedged intracoronary position could be quantitatively analyzed. Minimal lumen diameter, minimal cross-sectional area, percent diameter stenosis, and cross-sectional area stenosis were automatically measured with both the geometric and densitometric technique and were compared with the known phantom dimensions. When minimal lumen diameter was measured using the geometric approach, a nonsignificant underestimation of the phantom size was observed, with a mean difference of -0.06 +/- 0.14 mm. The larger mean difference observed with videodensitometry (-0.11 +/- 0.20 mm) was the result of the failure of the technique to differentiate the low lumen videodensities of two phantoms of smaller size (0.5 and 0.7 mm) from a dense background. Percent cross-sectional area stenosis measured with the two techniques showed a good correlation with the corresponding phantom measurements (mean difference between percent cross-sectional area stenosis calculated from the quantitative angiographic measurements and the corresponding phantom dimensions was equal to 2 +/- 6% for both techniques, correlation coefficient = 0.93 with both techniques, SEE = 5% with the geometric technique and 6% with the densitometric approach).(ABSTRACT TRUNCATED AT 250 WORDS

Effects of the mGluR2/3 agonist LY379268 on ketamine-evoked behaviours and neurochemical changes in the dentate gyrus of the rat

One of the functions of group 11 metabotropic glutamate receptors (mGluR2/3) is to modulate glutamate release. Thus, targeting mGluR2/3s might be a novel treatment for several psychiatric disorders associated with inappropriate glutamatergic neurotransmission, such as schizophrenia. In an effort to evaluate the antipsychotic properties of LY379268; a potent and selective mGluR2/3 agonist, we examined its effect on ketamine-evoked hyperlocomotion and sensorimotor gating deficit (PPI) in rats, an animal model of schizophrenia. We also measured the ex vivo tissue level of glutamate (Glu), dopamine (DA) and serotonin (5-HT) as well as the DA metabolites DOPAC and the major 5-HT metabolite HIAA to determine the neurochemical effects of ketamine (12 mg/kg) and LY379268 (1 mg/kg) in the dentate gyrus (DG). While LY379268 (1-3 mg/kg) reduced ketamine-evoked hyperlocomotion (12 mg/kg), it could not restore ketamine-evoked PPI deficits (4-12 mg/kg). In the DG we found that ketamine decreased Glu and DA levels, as well as HIAA/5-HT turnover, and that LY379268 could prevent ketamine effects on Glu level but not on monoamine transmission. These results may indicate that the inability of LY379268 to reverse PPI deficits is attributable to its lack of effect on ketamine-induced changes in monoamine transmission, but that LY379268 can prevent ketamine-evoked changes in glutamate, which is sufficient to block hyperlocomotion. In addition to the partial effectiveness of LY379268 in the ketamine model of schizophrenia, we observed a dual effect of LY379268 on anxious states, whereby a low dose of this compound (1 mg/kg) produced anxiolytic effects, while a higher dose (3 mg/kg) appeared to be anxiogenic. Additional work is needed to address a possible role of LY379268 in schizophrenia and anxiety treatment. (c) 2006 Elsevier Inc. All rights reserved

The Psychobiology of Authentic and Simulated Dissociative Personality States:The Full Monty

The etiology of dissociative identity disorder (DID) remains a topic of debate. Proponents of the fantasy model and the trauma model of DID have both called for more empirical research. To this end, the current study presents new and extended data analyses of a previously published (H2O)-O-15 positron emission tomography imaging study. This study included 29 subjects: 11 patients with DID and 10 high- and 8 low-fantasy-prone DID-simulating mentally healthy control subjects. All subjects underwent an autobiographical memory script-driven (neutral and trauma related) imagery paradigm in 2 (simulated) dissociative personality states (neutral and trauma related). Psychobiological and psychophysiological data were obtained. Results of the new post-hoc tests on the psychophysiological responses support the trauma model. New results of the brain imaging data did not support the fantasy model. This study extends previously published results by offering important new supporting data for the trauma model of DID.</p

Event-related fMRI responses in the human frontal eye fields in a randomized pro- and antisaccade task

We examined whether the frontal eye fields (FEF) are involved in the suppression of reflexive saccades. Simultaneous recording of horizontal eye movements and functional magnetic resonance imaging enabled us to perform a randomized pro- and antisaccade task and to sort blood oxygenation level dependent (BOLD) time series on the basis of task performance. Saccadic reaction time distributions were comparable across tasks indicating a similar effort in preprocessing of the saccades. Furthermore, we found similar BOLD activation in FEF during both correctly performed pro- and antisaccades. Frontal eye field activation started prior to target presentation and saccade generation. While we observed only few erroneous antisaccades, these were associated with a decrease in BOLD activity prior to target presentation, and increased BOLD activity after target presentation relative to correctly performed antisaccades. These findings are consistent with a role of the FEF in the suppression of reflexive saccades. The increase in activity after target presentation for antisaccade errors can only be indirectly linked to such a role but may also reflect activity related to the generation of a correction saccade. Frontal eye field BOLD activity may further represent general arousal, preparatory set, shortterm memory, or salience-map related activity

Somatosensory Profiles but Not Numbers of Somatosensory Abnormalities of Neuropathic Pain Patients Correspond with Neuropathic Pain Grading

Due to the lack of a specific diagnostic tool for neuropathic pain, a grading system to categorize pain as ‘definite’, ‘probable’, ‘possible’ and ‘unlikely’ neuropathic was proposed. Somatosensory abnormalities are common in neuropathic pain and it has been suggested that a greater number of abnormalities would be present in patients with ‘probable’ and ‘definite’ grades. To test this hypothesis, we investigated the presence of somatosensory abnormalities by means of Quantitative Sensory Testing (QST) in patients with a clinical diagnosis of neuropathic pain and correlated the number of sensory abnormalities and sensory profiles to the different grades. Of patients who were clinically diagnosed with neuropathic pain, only 60% were graded as ‘definite’ or ‘probable’, while 40% were graded as ‘possible’ or ‘unlikely’ neuropathic pain. Apparently, there is a mismatch between a clinical neuropathic pain diagnosis and neuropathic pain grading. Contrary to the expectation, patients with ‘probable’ and ‘definite’ grades did not have a greater number of abnormalities. Instead, similar numbers of somatosensory abnormalities were identified for each grade. The profiles of sensory signs in ‘definite’ and ‘probable’ neuropathic pain were not significantly different, but different from the ‘unlikely’ grade. This latter difference could be attributed to differences in the prevalence of patients with a mixture of sensory gain and loss and with sensory loss only. The grading system allows a separation of neuropathic and non-neuropathic pain based on profiles but not on the total number of sensory abnormalities. Our findings indicate that patient selection based on grading of neuropathic pain may provide advantages in selecting homogenous groups for clinical research

The Yale-Brown Obsessive-Compulsive Scale: Factor Structure of a Large Sample

The Yale Brown Obsessive-Compulsive scale (Y-BOCS) is a semi-structured interview considered to be the gold standard in the measurement of obsessive-compulsive disorder (OCD) severity, yet findings about its factorial structure are conflicting. This study aimed at comparing different models, and testing whether factorial structure differs along various sub-groups. Exploratory and confirmatory factor analyses were conducted on Y-BOCS scores of a large OCD patient group (n = 544). A three-factor structure (obsessions, compulsions, and resistance) provided the best fit for the data across different factor analytic procedures. The difference in goodness of fit between the original two factor (obsessions and compulsions) and the three-factor solutions seemed, however, very small. Since the two-factor solution is the original theory-driven structure, and the most widely used, we recommend the use of this factor

Locally increased P-glycoprotein function in major depression: a PET study with [C-11]verapamil as a probe for P-glycoprotein function in the blood-brain barrier

The aetiology of depressive disorder remains unknown, although genetic susceptibility and exposure to neurotoxins are currently being discussed as possible contributors to this disorder. In normal circumstances, the brain is protected against bloodborne toxic influences by the blood-brain barrier, which includes the molecular efflux pump P-glycoprotein (P-gp) in the vessel wall of brain capillaries. We hypothesized that P-gp function in the blood-brain barrier is changed in patients with major depression. Positron emission tomography Was used to measure brain uptake of [C-11]verapamil, which is normally expelled from the brain by P-gp. Cerebral Volume of distribution (V-T) of [C-11]verapamil was used as a measure of P-gp function. Both region-of-interest (ROI) analysis and voxel analysis using statistical parametric mapping (SPM2) were performed to assess regional brain P-gp function. We found that patients with a major depressive episode, using antidepressants, compared to health), controls showed a significant decrease of [C-11]verapamil uptake in different areas throughout the brain, in particular in frontal and temporal regions. The decreased [C-11]verapamil uptake correlates with an increased function of the P-gp protein and may be related to chronic use of psychotropic drugs, Our results may explain why treatment-resistant depression can develop

Citrate anticoagulation versus systemic heparinisation in continuous venovenous hemofiltration in critically ill patients with acute kidney injury: A multi-center randomized clinical trial

Introduction: Because of ongoing controversy, renal and vital outcomes are compared between systemically administered unfractionated heparin and regional anticoagulation with citrate-buffered replacement solution in predilution mode, during continuous venovenous hemofiltration (CVVH) in critically ill patients with acute kidney injury (AKI).Methods: In this multi-center randomized controlled trial, patients admitted to the intensive care unit requiring CVVH and meeting inclusion criteria, were randomly assigned to citrate or heparin. Primary endpoints were mortality and renal outcome in intention-to-treat analysis. Secondary endpoints were safety and efficacy. Safety was defined as absence of any adverse event necessitating discontinuation of the assigned anticoagulant. For efficacy, among other parameters, survival times of the first hemofilter were studied.Results: Of the 139 patients enrolled, 66 were randomized to citrate and 73 to heparin. Mortality rates at 28 and 90 days did not differ between groups: 22/66 (33%) of citrate-treated patients died versus 25/72 (35%) of heparin-treated patients at 28 days, and 27/65 (42%) of citrate-treated patients died versus 29/69 (42%) of heparin-treated patients at 90 days (P = 1.00 for both). Renal outcome, i.e. independency of renal replacement therapy 28 days after initiation of CVVH in surviving patients, did not differ between groups: 29/43 (67%) in the citrate-treated patients versus 33/47 (70%) in heparin-treated patients (P = 0.82). Heparin was discontinued in 24/73 (33%) of patients whereas citrate was discontinued in 5/66 (8%) of patients (P &#60; 0.001). Filter survival times were superior for citrate (median 46 versus 32 hour