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Wagner F Gattaz

Publications and source records attributed to Wagner F Gattaz.

At least 19 recordsLinked to original sources
PubMed2006

World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for biological treatment of schizophrenia, part 2: long-term treatment of schizophrenia.

These guidelines for the biological treatment of schizophrenia were developed by an international Task Force of the World Federation of Societies of Biological Psychiatry (WFSBP). The goal during the development of these guidelines was to review systematically all available evidence pertaining to the treatment of schizophrenia, and to reach a consensus on a series of practice recommendations that are clinically and scientifically meaningful based on the available evidence. These guidelines are intended for use by all physicians seeing and treating people with schizophrenia. The data used for developing these guidelines have been extracted primarily from various national treatment guidelines and panels for schizophrenia, as well as from meta-analyses, reviews and randomised clinical trials on the efficacy of pharmacological and other biological treatment interventions identified by a search of the MEDLINE database and Cochrane Library. The identified literature was evaluated with respect to the strength of evidence for its efficacy and then categorised into four levels of evidence (A-D). This second part of the guidelines covers the long-term treatment as well as the management of relevant side effects. These guidelines are primarily concerned with the biological treatment (including antipsychotic medication, other pharmacological treatment options, electroconvulsive therapy, adjunctive and novel therapeutic strategies) of adults suffering from schizophrenia.

Antipsychotic Agents↗
PubMed2005

Complex slow potential generators in a simplified attention paradigm.

We have recently obtained evidence for complex multifocal, individually variable generators of slow cortical potentials, elicited during performance of visual tasks involving expecting attention, comparison and memory [Basile, L.F.H., Ballester, G., Castro, C.C., and Gattaz, W.F., 2002. Multifocal slow potential generators revealed by high-resolution EEG and current density reconstruction. Int. J. Psychophysiol., 45 (3), 227-240; Basile, L.F.H, Baldo, M.V., Castro, C.C., and Gattaz, W.F. 2003. The generators of slow potentials obtained during verbal, pictorial and spatial tasks. Int. J. Psychophysiol., 48, 55-65]. The cue-target aspect of traditional paradigms for attention studies is equivalent to 'warning S1'-'imperative S2' in slow potential designs. We simplified Posner's spatial cueing task [Posner, M.I. 1980. Orienting of attention.Q. J. Exp. Psychol. Feb;32 (1), 3-25; Posner, M.I., Snyder, C.R., Davidson, B.J. 1980. Attention and the detection of signals. J Exp Psychol. Jun; 109 (2), 160-174] to temporal cuing only, by using visual cues to indicate the mere presence, on a known central position, of the eventual target (17 ms duration, +/-0.3 degrees grey circle). We recorded slow potentials on 12 healthy subjects, by 124-channel EEG system (Neuroscan Inc.), and modeled their generators using current density reconstruction (CDR) by L(p) 1.2 norm minimization ("Curry V4.6", Neurosoft Inc.) applied to the target onset time. MRIs were obtained for each subject for constraining source models to individual brain anatomy. Average slow potentials were computed from above 60 artifact-free EEG-epochs (ISI=1.6 s, average ITI=2.5 s). We tabulated individual cortical current distributions by cytoarchitectonic area of Brodmann, after scaling into negligible, low, moderate and strong local density, based on percentile bands with respect to absolute maximum current. Despite the task's simplicity, the main result was individual variability and complexity in both scalp voltage and cortical current distributions. As observed in our previous studies, there was strong intersubject variability in the exact distribution of task-related cortical activity. Only parietal area 7 bilaterally was non-negligibly active in all subjects (currents above 10% maximum). As opposed to drawing conclusions based on group averaged data, we propose that activity by cytoarchitectonic area be ranked and statistically analysed only after being scaled on each individual. Based on the present results, the concept of a universal attention-related set of cortical areas if restricted to common areas across subjects is challenged, since even area 7 may no longer be common when the sample size becomes larger. We discuss the fact that group averaging may de-emphasize weakly but consistently active areas, and emphasize strongly but inconsistently active ones.

Adult↗
PubMed2005

The Short Cognitive Performance Test (SKT): a preliminary study of its psychometric properties in Brazil.

BACKGROUND: Most instruments designed to detect dementia can lack appropriate sensitivity in the early stages of Alzheimer's disease (AD), and are subject to educational bias. The Short Cognitive Performance Test (Syndrom-Kurztest, SKT) is considered a suitable instrument to measure cognitive decline as it assesses memory, attention, and related cognitive functions, taking into account the speed of information processing. OBJECTIVES: The aim of this study was to examine the psychometric characteristics of the SKT as a dementia screening instrument in a Brazilian population sample, as compared to the Mini-mental State Examination (MMSE) and the Clock-Drawing Test (CDT). The effect of educational level on performance in the three screening tests was also verified. METHODS: Fifty-one elderly subjects were assessed. Consensus diagnoses were established by an expert multidisciplinary team, considering clinical, neuropsychological and neuroimaging data. Subjects were further classified into those with (1) mild and moderate AD, (2) non-Alzheimer's dementia, (3) mild cognitive impairment, and (4) controls, according to National Institute for Communicative Disorders and Stroke--Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) criteria. RESULTS: Statistical analyses revealed high internal consistency for the SKT (Cronbach's alpha = 0.80) and significant correlations between the total score and the SKT subscores separately (p < 0.01). Comparison of the three tests revealed strong correlations between the SKT and the MMSE (r = -0.66, p < 0.0001) and between the SKT and the CDT (r = -0.57, p < 0.0001). The SKT, MMSE and CDT scores were correlated with education. CONCLUSIONS: The Brazilian version of the SKT maintains its original psychometric properties and displays significant correlation with previously validated screening tools for dementia. Like other dementia screening tests, the SKT is subject to educational bias.

Adult↗
PubMed2005

Inhibition of calcium-independent phospholipase A2 activity in rat hippocampus impairs acquisition of short- and long-term memory.

RATIONALE: Phospholipase A(2) (PLA(2)) is a family of enzymes that cleave membrane phospholipids generating important lipid mediators in signal transduction. In rat hippocampal slices, both intracellular cytosolic Ca(2+)-dependent PLA(2) (cPLA(2)) and Ca(2+)-independent PLA(2) (iPLA(2)) have been implicated in mechanisms of synaptic plasticity underlying memory processes. In mice, intraperitoneal injections of a selective iPLA(2) inhibitor impaired spatial learning. Accordingly, reduced cPLA(2) and iPLA(2) activities were found in postmortem hippocampus of patients with Alzheimer's disease. OBJECTIVE: This study investigates the effects of injections of PLA(2) inhibitors directly into rat hippocampus on the acquisition of short-term (STM) and long-term memory (LTM) of a one-trial step-down inhibitory avoidance (IA) task. METHODS: Wistar rats were bilaterally implanted with cannulae in the CA1 region of the dorsal hippocampus. After surgery, the rats received bilateral injections of a vehicle, or of dual cPLA(2) and iPLA(2) inhibitors (MAFP or PACOCF(3)), or a selective iPLA(2) inhibitor (bromoenol lactone) before training in IA. The animals were tested 1.5 h (for STM) and 24 h (for LTM) after training. RESULTS: Significant inhibition of iPLA(2) activity in rat hippocampus impaired acquisition of STM and LTM. Memory impairment did not result from neuronal death after iPLA(2) inhibition. Moreover, IA training per se increased significantly hippocampal PLA(2) activity. CONCLUSION: The present results suggest a functional effect of hippocampal PLA(2) on the neurochemistry of memory acquisition and support the hypothesis that reduced PLA(2) activity may contribute to memory impairment in Alzheimer's disease.

Animals↗
PubMed2005

Nogo CAA 3'UTR Insertion polymorphism is not associated with Schizophrenia nor with bipolar disorder.

The Nogo gene maps to 2p14-p13, a region consistently associated with schizophrenia and bipolar disorder. The association of a polymorphism in Nogo was previously investigated by two groups, with divergent results. In this report, using an alternative approach, we evaluated this same polymorphism in 725 individuals, including patients with schizophrenia, bipolar disorder, normal controls and non-human primate samples. Our results indicate that the polymorphism is not associated with any of these diseases, but has a remarkably biased distribution in ethnic groups. Genotyping of primate samples, suggest that this polymorphism is a recent event in human speciation.

Adult↗
PubMed2005

Reduced phospholipid breakdown in Alzheimer's brains: a 31P spectroscopy study.

BACKGROUND: Abnormalities of membrane phospholipid metabolism have been described in Alzheimer's disease (AD). We investigated, with the aid of (31)P magnetic resonance spectroscopy, the in vivo intracerebral availability of phosphomonoesters (PME) and phosphodiesters (PDE) in patients with AD. METHODS: Eighteen outpatients with mild or moderate probable AD and 16 nondemented elderly volunteers were assessed with the Cambridge Examination for Mental Disorders of the Elderly (CAMDEX) and its cognitive subscale of the CAMDEX schedule (CAMCOG). Scans were performed on a 1.5 T magnetic resonance imager addressing a 40-cm(3) voxel in the left prefrontal cortex. Main outcome measures were mean relative peak areas of PME and PDE, which provide an estimate of membrane phospholipid metabolism. RESULTS: PME resonance and the PME/PDE ratio were increased in AD patients as compared to controls (p<0.05). PME was negatively correlated with global cognitive performance as shown by the Mini-Mental State Examination (r(s)=-0.36, p=0.05) and CAMCOG scores (r(s)=-0.49, p=0.007), as well as with discrete neuropsychological functions, namely, memory (r(s)=-0.53, p=0.004), visual perception (r(s)=-0.54, p=0.003), orientation (r(s)=-0.36, p=0.05), and abstract thinking (r(s)=-0.48, p=0.01). CONCLUSIONS: We provide evidence of reduced membrane phospholipid breakdown in the prefrontal cortex of mild and moderately demented AD patients. These abnormalities correlate with neuropsychological deficits that are characteristic of AD.

Aged↗
PubMed2005

Transcranial magnetic stimulation accelerates the antidepressant effect of amitriptyline in severe depression: a double-blind placebo-controlled study.

BACKGROUND: Transcranial magnetic stimulation (TMS) is a noninvasive method to stimulate the cortex, and the treatment of depression is one of its potential therapeutic applications. Three recent meta analyses strongly suggest its benefits in the treatment of depression. The present study investigates whether repetitive TMS (rTMS) accelerates the onset of action and increases the therapeutic effects of amitriptyline. METHODS: Forty-six outpatients meeting DSM-IV criteria for nonpsychotic depressive episode were randomly assigned to receive rTMS (n = 22) or sham repetitive TMS (sham) (n = 24) during 4 weeks over dorsolateral prefrontal cortex (DLPFC) in this double-blind controlled trial. All patients were concomitantly taking amitriptyline (mean dose 110 mg/d). The rTMS group received 20 sessions (5 sections per week) of 5 Hz rTMS (120% of motor threshold and 1250 pulses per session). Sham stimulation followed the same schedule, however, using a sham coil. The efficacy variables were the Hamilton Depression Rating Scale-17 items (HAM-D/17), the Montgomery-Asberg Depression Rating Scale (MADRS), a Visual Analogue Scale (VAS), and the Clinical Global Impression (CGI). Tolerability was assessed by clinical examination and a safety screening of TMS side effects. RESULTS: Repetitive TMS had a significantly faster response to amitriptyline. There was a significant decrease in HAM-D/17 scores, already after the first week of treatment (p < .001 compared with baseline and p < .001 compared with sham). The decrease in HAM-D/17 scores in the rTMS group was significantly superior compared with the sham group throughout the study (p < .001 at fourth week). CONCLUSIONS: Repetitive TMS at 5 Hz accelerated the onset of action and augmented the response to amitriptyline.

Adult↗
PubMed2005

Childhood meningitis increases the risk for adult schizophrenia.

OBJECTIVE: We investigated the hypothesis that a meningitic infection in childhood may increase the risk of a psychiatric disorder in adulthood. METHOD: We conducted a follow-up study of 190 individuals affected by a meningitis infection the first 4 years of life, during an epidemic in São Paulo, Brazil, between 1971 and 1974. As a control group, we investigated 156 siblings of the meningitis patients who were not affected by meningitis at childhood. RESULTS: In the 190 cases of meningitis, we found eight (4.2%) cases of schizophrenia against none in the controls, and 40 (21.0%) cases of life occurrence of psychotic symptoms compared to 12 (7.6%) cases in the control group (P<0.001). We found no differences between the two groups regarding the occurrence of other psychiatric disorders and of neurological soft signs. CONCLUSION: Meningitis during childhood significantly increased the risk of schizophrenia in particular in adulthood, and of psychosis in general.

Adolescent↗
PubMed2005

World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for biological treatment of schizophrenia, Part 1: acute treatment of schizophrenia.

These guide lines for the biological treatment of schizophrenia were developed by an international Task Force of the World Federation of Societies of Biological Psychiatry (WFSBO). The goal during the development of these guidelines was to review systematically all available evidence pertaining to the treatment of schizophrenia, and to reach a consensus on a series of practice recommendations that are clinically and scientifically meaningful based on the available evidence. These guidelines are intended for use by all physicians seeing and treating people with schizophrenia. The data used for developing these guidelines have been extracted primarily from various national treatment guidelines and panels for schizophrenia, as well as from meta-analyses, reviews and randomised clinical trials on the efficacy of pharmacological and other biological treatment interventions identified by a search of the MEDLINE database and Cochrane Library. The identified literature was evaluated with respect to the strength of evidence for its efficacy and then categorised into four levels of evidence (A-D). This first part of the guidelines covers disease definition, classification, epidemiology and course of schizophrenia, as well as the management of the acute phase treatment. These guidelines are primarily concerned with the biological treatment (including antipsychotic medication, other pharmacological treatment options, electroconvulsive therapy, adjunctive and novel therapeutic strategies) of adults suffering from schizophrenia.

Acute Disease↗
PubMed2005

Olanzapine versus ziprasidone: results of a 28-week double-blind study in patients with schizophrenia.

OBJECTIVE: The efficacy and safety of olanzapine were compared with those of ziprasidone. METHOD: This was a multicenter randomized, double-blind, parallel-group, 28-week study of patients with schizophrenia. Patients were randomly assigned to treatment with 10-20 mg/day of olanzapine or 80-160 mg/day of ziprasidone. The primary efficacy measure was the Positive and Negative Syndrome Scale total score. Secondary efficacy and safety measures included Positive and Negative Syndrome Scale subscales as well as mood, quality of life, and extrapyramidal symptom scales. Safety was evaluated by recording treatment-emergent adverse events and measuring vital signs and weight. RESULTS: The study was completed by significantly more olanzapine-treated patients (165 of 277, 59.6%) than ziprasidone-treated patients (115 of 271, 42.4%). At 28 weeks, the olanzapine-treated patients showed significantly more improvement than the ziprasidone-treated patients on the Positive and Negative Syndrome Scale overall scale and all subscales and on the Clinical Global Impression ratings of severity of illness and improvement. The responder rate was higher for olanzapine than for ziprasidone. Extrapyramidal symptoms were not significantly different between groups in change-to-endpoint analyses, but results favored olanzapine on baseline-to-maximum changes. Weight change was significantly greater with olanzapine (mean=3.06 kg, SD=6.87) than with ziprasidone (mean=-1.12 kg, SD=4.70). Fasting lipid profiles were significantly superior in the ziprasidone group; there was no significant difference in fasting glucose level. CONCLUSIONS: Olanzapine treatment resulted in significantly greater psychopathology improvement and higher response and completion rates than ziprasidone treatment, while ziprasidone was superior for weight change and lipid profile.

Adult↗
PubMed2004

Widespread electrical cortical dysfunction in schizophrenia.

The purpose of this study was to compare slow cortical electrical activity between healthy and schizophrenic individuals using 123-channel EEG and current density reconstruction (CDR). Twenty-nine healthy subjects and 14 drug-free patients performed three visual paired-associate tasks (verbal, pictorial and spatial). We modeled the generators of the slow potentials (SPs) at their peak amplitude by Lp-norm minimization using individual MRIs to model the volume conductor and source. Activity in each architectonic area of Brodmann was scored with respect to individual maximum current by a percentile method. Resulting scores by cortical area were analyzed by multivariate analysis of variance (MANOVA) with planned comparisons, to search for differences among levels. Results showed a multifocal pattern of current density foci comprising the SP generators, including frontal and posterior cortices in all subjects. A few cortical areas, not exclusively frontal, were observed to significantly differ between groups. Moreover, changes in patients' frontal activity were not exclusively to lower scores or 'hipofrontality': overall effects (all tasks collapsed) included increased electrical activity in right area 10, left 38 and 47 bilaterally, and decreased activity in right area 6 and left areas 39, 21 and 19. A few additional areas showed significantly altered activity only in particular tasks. We conclude that the present method, by preserving individual anatomical and functional information, indicates bidirectional patterns of altered electrical activity in specific cortical association areas in schizophrenia, which are not compatible with the exclusive 'hipofrontality' hypothesis. Our results agree with the hypothesis of schizophrenia as a syndrome resulting from abnormalities in multiple encephalic foci.

Adult↗
PubMed2004

Altered thalamic membrane phospholipids in schizophrenia: a postmortem study.

BACKGROUND: Membrane lipids are important mediators of neuronal function. In a postmortem study, we measured membrane lipid components in the left thalamus of schizophrenic patients. This region might play an important role in the pathophysiology of schizophrenia and has not been studied thus far with respect to its membrane lipid composition. METHODS: The study included 18 chronic schizophrenic patients and 23 healthy control subjects. Using lipid extraction and thin-layer chromatography, we measured membrane phospholipids, galactocerebrosides 1 and 2, and sulfatides in thalamus homogenate. RESULTS: The main membrane phospholipid phosphatidylcholine and the major myelin membrane components sphingomyelin and galactocerebrosides 1 and 2 were found to be decreased in schizophrenic patients. In contrast, phosphatidylserine was increased. These lipid contents did not correlate with postmortem intervals and medication doses. There was no difference in the membrane phospholipids lysophosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, and phosphatidylglycerol or in sulfatides. CONCLUSIONS: Our results confirm findings of magnetic resonance imaging, postmortem, and gene expression studies. They support the notion of an increased phospholipid breakdown in schizophrenia as a sign for decreased myelination and oligodendrocyte dysfunction.

Aged↗
PubMed2004

Conjugated estrogens as adjuvant therapy in the treatment of acute schizophrenia: a double-blind study.

In a double-blind, placebo controlled study, conjugated estrogens (CE) (0.625 mg/day) were added to a fixed dosage of haloperidol (5 mg daily). Forty-four female inpatients with acute schizophrenia were included in the study and randomized to one of the groups; 40 patients completed the trial. They were followed for 28 days and evaluated periodically with the BPRS, Negative Symptoms Rating Scale, Simpson Angus Extrapyramidal Rating Scale and UKU rating scale. Hormonal concentrations (estradiol, estrone, progesterone, FSH, LH and prolactine) were measured at baseline and weekly throughout the trial. Both groups showed similar clinical improvement during the evaluation, although there was a trend for the CE group to show a better improvement than the placebo group (p < 0.10). Side effects and the use of anticholinergics were similar in both groups. Conjugated estrogens caused elevation only of estrone levels in the CE group; estradiol and prolactin showed a similar profile for both groups. Our negative findings regarding the antipsychotic effect of conjugated estrogens does not preclude, however, a possible efficacy of other estrogens, such as 17-beta-estradiol, in schizophrenia.

Acute Disease↗
PubMed2004

Inhibition of platelet phospholipase A2 activity by catuaba extract suggests antiinflammatory properties.

In the inflammation process, phospholipase A2 (PLA2) catalyses the cleavage of the sn-2 ester-linked fatty acids from phospholipids, being the enzyme responsible for arachidonic acid (AA) release by cells for the biosynthesis of the prostaglandins and thromboxanes via the cyclooxygenase system, and the leukotrienes and eicosatetraenoids via the lipoxygenase pathway. AA mobilization by PLA2 and subsequent prostaglandins synthesis is considered to be a pivotal event in inflammation. Therefore, drugs that inhibit PLA2, thus blocking the COX and LOX pathways in the AA cascade, may be effective in the treatment of inflammatory processes. New strategies for the treatment of inflammatory processes could be detected by a search for active principles of vegetal origin that control the lipid mediator production by inhibition of PLA2. The present data are part of a wide explorative investigation on the effects of Trichilia catigua (catuaba), which found that PLA2 activity was totally inhibited by catuaba at a concentration of 120 microg/mL, suggesting that this natural substance may have antiinflammatory properties.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2003

[Münchhausen syndrome: diagnosis and management].

The authors review the literature on Münchhausen syndrome, and ilustrate the clinical features of the disorder with the description of a characteristic case. Diagnosis and differential diagnosis are discussed with regard to other somatoform disorders such as conversion disorder and somatization disorder as well as to malingering and schizophrenia. The awareness of general practitioners and surgeons regarding this syndrome may avoid the exposure of these patients to serious complications of unnecessary medical and surgical procedures. The management of Müchhausen syndrome is aggravated by the low compliance in these patients. Early diagnosis could to a considerable extent prevent the iatrogenic risks. The authors recommend that patients presenting the psychopathological features of a Münchhausen syndrome should be conservatively observed and an attempt to clarify both the medical and the psychiatric diagnosis should be made before any invasive procedure is undertaken.

Adult↗
PubMed2003

Increased phospholipase A2 activity in schizophrenia with absent response to niacin.

An absent response to the niacin skin test has been reported to occur in about 80% of schizophrenic patients, as compared to 20% of healthy individuals. Niacin provokes redness in skin caused by a capillary vasodilatation mediated by prostaglandins. The metabolism of prostaglandins is regulated by the enzyme phospholipase A2 (PLA2). Several studies have reported increased PLA2 activity in schizophrenia. In this study we investigated the relationship between niacin response and PLA2 activity in 38 drug-free schizophrenic patients and in 28 healthy controls. Twenty-two of these patients were reevaluated after 8 weeks under treatment with new generation antipsychotic drugs. Niacin response was absent in 23% of the schizophrenic patients and in 14% in controls (n.s.). PLA2 activity was higher in schizophrenics than in controls (344+/-115 vs. 290+/-71 pmol/ml/min; p=0.03). Patients with absent response to niacin had the highest PLA2 activity as compared to those with positive response (426+/-155 vs. 319+/-111; p=0.02). After 8 weeks on antipsychotic treatment, PLA2 activity was reduced (355+/-115 before, 267+/-39 after, p=0.001) and 4 out of 13 patients with absent response to niacin converted to positive. The reduction of PLA2 activity in these patients was higher than in patients who remained with absent response (36% vs. 23%). Our data support the findings that absent response to niacin is more frequent in schizophrenic than in healthy individuals although the magnitude of the difference was smaller than that reported in the literature. The relationship between absent response to niacin in schizophrenia and increased PLA2 activity suggests further that the skin test may be useful to easily identify a subgroup of patients with a disordered phospholipid metabolism.

Adult↗
PubMed2003

Rightward cerebral asymmetry in subtypes of schizophrenia according to Leonhard's classification and to DSM-IV: a structural MRI study.

Although well documented, brain structural abnormalities in schizophrenia are non-specific, and morphometric parameters show significant overlap between patients and healthy controls. Such inconsistencies in neuroimaging findings could represent different levels of severity along a single pathogenic process or distinct clinical and etiopathological psychoses within a schizophrenic spectrum. The aim of the present study was the investigation of distinct brain abnormalities in different subtypes of schizophrenia. Forty patients were classified according to DSM-IV and Leonhard's classifications. Psychopathology was assessed by the Positive and Negative Syndrome Scale (PANSS) and the Negative Symptom Rating Scale (NSRS). Patients were compared to 20 healthy volunteers on volumetric measures of cerebral structures (hemisphere, hippocampus and planum temporale) and ventricular-brain ratio (VBR) obtained by magnetic resonance imaging. Patients showed rightward asymmetry of cerebral hemispheres and increased VBR. Rightward asymmetry correlated with severity of negative symptoms and prevailed in the systematic forms of Leonhard, suggesting a distinct pattern of left hemisphere abnormality in this subgroup of psychoses. Increased VBR values showed a single normal distribution in the subgroups, indicating that ventricular enlargement is not restricted to a subgroup but is present to a certain degree in all cases.

Adult↗