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At least 199 records · Page 11Linked to original sources
PubMed2001

Structural brain abnormalities in patients with schizophrenia, epilepsy, and epilepsy with chronic interictal psychosis.

Chronic interictal psychotic syndromes, often resembling schizophrenia, develop in some patients with epilepsy. Although widespread brain abnormalities are recognized as characteristic of schizophrenia, prevailing but controversial hypotheses on the co-occurrence of epilepsy and psychosis implicate left temporal lobe pathology. In this study, quantitative MRI methods were used to address the regional specificity of structural brain abnormalities in patients with epilepsy plus chronic interictal psychosis (E+PSY, n=9) relative to three comparison groups: unilateral temporal lobe epilepsy without chronic psychosis (TLE, n=18), schizophrenia (SCZ, n=46), and healthy control subjects (HC, n=57). Brain measures, derived from a coronal spin-echo MRI sequence, were adjusted for age and cerebral volume. Relative to HC, all patient groups had ventricular enlargement and smaller temporal lobe, frontoparietal, and superior temporal gyrus gray matter volumes, with the extent of these abnormalities greatest in E+PSY. Only TLE had temporal lobe white matter deficits, as well as smaller hippocampi, which were ipsilateral to the seizure focus. Structural brain abnormalities in E+PSY are not restricted to the left temporal lobe. The confluence of cortical gray matter deficits in E+PSY and SCZ suggests salience to chronic psychosis.

Adult↗
PubMed1987

[BB creatine phosphokinase activity of the brain structures of mentally healthy persons and schizophrenics].

Creatine phosphokinase (CPK) activity has been determined in certain brain structures of schizophrenics and control subjects. It has been found that CPK activity in different structures of the normal human brain is heterogeneous, being the maximal in the occipital cortex (2.80 U/mg of protein) and thalamus (1.87 U/mg of protein) and the minimal in the temporal cortex (0.30 U/mg). In schizophrenic patients, CPK activity was significantly depressed (by 80-90%, P less than 0.001) in the occipital cortex and thalamus, as well as in the substantia nigra, limbic cortex and grey tuber (P less than 0.001) but remaining unaltered in the frontal, temporal and parietal cortex. It has been demonstrated that decrease in CPK activity does not depend on the post-mortem interval, sex and age of those examined or the psychotropic therapy conducted but appears to be related to a pathological process in the nervous tissue.

Aged↗
PubMed2005

Metabolism and receptor binding of serotonin in brain structures during performance of a conditioned passive avoidance response.

The levels of serotonin and its metabolite 5-hydroxyindoleacetic acid, monoamine oxidase activity, and the specific binding of the radioligand [3H]serotonin were measured in the prefrontal cortex, striatum, amygdaloid complex, hippocampus, and periacqueductal gray matter of the midbrain in rats at different time points after training to a conditioned passive avoidance reaction. Changes in serotoninergic activity were found to be characteristic only for the process of reproducing the conditioned reaction. The metabolism and serotonin receptor binding in these brain structures did not change immediately after the training period or one day after this, or in conditions of failure to reproduce the reaction because of amnesia, or in untrained animals. The involvement of the brain serotoninergic system in the process of performing the conditioned reaction was found to demonstrate a spatial-structural selectivity: the metabolism and receptor binding of serotonin changed in the amygdaloid complex, periacqueductal gray matter, and the striatum, while no changes were seen in the hippocampus or prefrontal cortex. All three brain structures showed decreases in [3H]serotonin receptor binding of. Serotonin levels did not change, though the amygdaloid complex and periacqueductal gray matter showed increases in oxidative deamination of serotonin and increases in the active transport of the metabolite, while the striatum showed decreases in serotonin catabolism. The differences in the catabolism of this neurotransmitter suggest that the decrease in serotonin receptor binding in these brain structures depends on different synaptic processes--presynaptic in the striatum and postsynaptic in the amygdaloid complex and periacqueductal gray matter. It is concluded that the decrease in the functional activity of serotoninergic transmission in the amygdaloid complex and periacqueductal gray matter is one of the mechanisms involved in activation of the emotiogenic system triggering the process of reproduction of the memory trace.

Animals↗
PubMed2004

[Morphochemical characteristic of rat brain structures after exposure to delta-sleep inducing peptide following long-term amphetamine administration].

The aim of this work, that was carried out using Wistar rats, was to characterize the response of neurons of different morphofunctional types to amphetamine administration and to study the possibility of correction of these changes by delta-sleep inducing peptide (DSIP). Single intraperitoneal injection of 60 microg/kg of DSIP following a long term amphetamine administration (2.5 mg/kg for 3 weeks) was shown to result in normalization of brain metabolism, that was disturbed by the drug. The correcting DSIP effect was found in rat brain structures judging by the parameters of the state of proteins in neurons of sensomotor cortex and caudate nucleus and by the activity of enzymes of neurotransmitter metabolism, such as type A and B monoamine oxidases and acetylcholine esterase, that was determined in subfractions of the same brain structures. DSIP modulating effect in phenamine stereotypy supports its role as an adaptogen of intercenter relations in CNS pathology.

Acetylcholinesterase↗
PubMed2005

Age-related changes of normal adult brain structure: analysed with diffusion tensor imaging.

BACKGROUND: It is known that the brain structure changes with normal aging. The objective of this study was to quantify the anisotropy and average diffusion coefficient (DCavg) of the brain in normal adults to demonstrate the microstructure changes of brain with aging. METHODS: One hundred and six normal adults were examined with diffusion tensor imaging (DTI). The fractional anisotropy (FA), 1-volume ratio (1-VR), relative anisotropy (RA) and average diffusion coefficient (DCavg) of different anatomic sites of brain were measured, correlated with age and compared among three broad age groups. RESULTS: Except in lentiform nucleus, the anisotropy increased and DCavg decreased with aging. Both anisotropy and DCavg of lentiform nucleus increased with aging. The normal reference values of DTI parameters of normal Chinese adult in major anatomic sites were acquired. CONCLUSIONS: DTI data obtained noninvasively can reflect the microstructural changes with aging. The normal reference values acquired can serve as reference standards in differentiation of brain white matter diseases.

Adult↗
PubMed1991

Comparison of functional and structural brain disturbances in Wilson's disease.

We assessed the functional and structural brain disturbances in Wilson's disease (WD) by evoked potentials (EPs) and magnetic resonance imaging (MRI). All the 25 neurologically symptomatic and 44% of the 16 asymptomatic patients, assessed by both EPs (n = 48) and imaging (n = 41), had at least 1 abnormality of either prolonged EP conduction times, imaging-outlined presence of cerebral lesions, or brain atrophy. Our findings indicate that EPs and MRI are sensitive techniques for the evaluation of brain involvement in WD.

Adult↗
PubMed1991

Quantitative development of brain and brain structures in birds (galliformes and passeriformes) compared to that in mammals (insectivores and primates).

The brain weight and brain structure volumes of galliform and passeriform birds were calculated and related to body weight. The total brains and 14 brain regions were investigated in order to calculate factors by which these structures in passeriforms exceed those in galliforms in size. The larger passeriform brains have larger telencephala, especially ventral hyperstriata and neostriata. The enlargement of total brain and telencephalon resembles that in primates, compared to insectivores, within mammals. The enlargement of the ventral hyperstriata + neostriata in passeriforms is fundamentally similar to that of the isocortex in mammals: it reflects an expansion of multimodal integrational capacities, as the ventral hyperstriatum and neostriatum are occupied exclusively or primarily by multimodal integrational areas as is the isocortex.

Animals↗
PubMed2001

Association of an interleukin-1beta genetic polymorphism with altered brain structure in patients with schizophrenia.

OBJECTIVE: This study investigated the effect on brain morphology of an interleukin-1beta genetic polymorphism (C-->T transition at position -511) in patients with schizophrenia. METHOD: In vivo magnetic resonance imaging and genotype analysis were used in the examination of 44 male schizophrenic patients and 48 healthy male comparison subjects. RESULTS: No association between the interleukin-1beta polymorphism and schizophrenia was detected. Within the patient group, bifrontal-temporal gray matter volume deficits and generalized white matter tissue deficits in allele 2 carriers (genotype T/T or C/T) were found. In contrast, the interleukin-1beta polymorphism had no influence on brain morphology within the healthy subjects. CONCLUSIONS: The data suggest that allele 2 within the promoter region of the interleukin-1beta gene at position -511 contributes to structural brain alterations in patients with schizophrenia.

Adolescent↗
PubMed1995

The effect of white matter hyperintensity volume on brain structure, cognitive performance, and cerebral metabolism of glucose in 51 healthy adults.

OBJECTIVE: To assess the association of MRI white matter hyperintensities (WMHI) with cognitive performance, cerebral structure, and cerebral metabolism in 51 healthy individuals aged 19 to 91 years without cerebrovascular risk factors. BACKGROUND: Abnormal white matter signals have been associated with brain atrophy, reduced cerebral blood flow, focal neurologic signs, gait disorder, and poorer neuropsychological test performance. Most studies of WMHI, however, include subjects with hypertension or other identifiable causes of cerebrovascular disease that may have an independent effect on brain structure and function. To assess brain changes associated with WMHI independent of cerebrovascular risk factors, we determined WMHI volume, brain volume, cerebral metabolism, and cognitive performance for a group of subjects free of medical illness. Regional cerebral metabolism and cognitive domains were also assessed to evaluate the possible role of frontal lobe dysfunction in subjects with WMHI. DESIGN: Cross-sectional study of 51 very healthy subjects aged 19 to 91 years. METHODS: WMHI, brain, and CSF volumes were determined by MRI segmentation. Neuropsychological tests were employed to assess multiple cognitive domains. Brain metabolism was determined from 18-fluoro-2-deoxy-D-glucose PET. Multivariate relations were tested with stepwise linear regression. Models included the potential confounders of age and education where appropriate. RESULTS: The distribution of WMHI volume was bimodal, with five subjects having WMHI volumes beyond three SDs from the normally distributed population. A WMHI volume of greater than 0.5% of intracranial volume was considered abnormal. Within the multivariate models, WMHI volumes were significantly predictive of increased ventricular volume, reduced brain volume, and reduced cognitive scores. Subjects with greater than 0.5% WMHI volume also had significantly lower frontal lobe metabolism, significantly higher systolic blood pressure, significantly larger ventricular volume, and significantly lower scores on frontal lobe-mediated neuropsychological tests than age-matched controls. CONCLUSION: WMHI volume is associated with structural and functional brain changes even within a group of very healthy individuals. WMHI is associated with poorer frontal lobe cognitive function and, when severe, is accompanied by significantly reduced frontal lobe metabolism. Subjects with large WMHI volumes have significantly higher systolic blood pressure, brain atrophy, reduced cerebral metabolism, and lower scores on tests of frontal lobe function than age-matched controls. Large amounts of WMHI are, therefore, pathologic and may be related to elevated systolic blood pressure even when it is within the normal age-related range.

Adult↗
PubMed2001

[Structural brain changes in patients with schizophrenic psychoses. From focal pathology to network disorder].

Schizophrenia is a brain disorder characterized by a heterogeneous clinical symptomatology. Accordingly, many structural brain changes are not associated directly with clinical symptoms. These structural changes can be detected in the frontotemporal cortex and may correlate with the course of the disease. The most important etiological concept is the neurodevelopmental hypothesis according to which developmental, morphologically detectable changes predispose for the acquisition of schizophrenia. The relevance of neurodegenerative components also remains to be determined. However, it is becoming increasingly clear that schizophrenia is not associated with pathological changes in a circumscribed brain region but with widely distributed morphological changes. Presently, the leading hypothesis for explaining these changes is a frontotemporolimbic network disturbance with cytoarchitectural changes in the heteromodal association cortex. Present research therefore focuses on testing this theory using functional imaging on a macroscopic level and examination of the neuronal cytoarchitecture on a microscopic level.

Brain↗
PubMed2004

A select group of perpetrators of domestic violence: evidence of decreased metabolism in the right hypothalamus and reduced relationships between cortical/subcortical brain structures in position emission tomography.

In an earlier study, we reported that some perpetrators of domestic violence evidenced exaggerated fear-related responses to the panicogenic agent sodium lactate. In the current study, we employed positron emission tomography (PET) to investigate our hypothesis that there are differences in the neural structures and/or pathways that mediate and control the expression of fear-induced aggression in perpetrators of domestic violence. Regional cerebral glucose metabolism was measured in eight male perpetrators of domestic violence who fulfilled DSM-III-R criteria for alcohol dependence (DV-ALC), 11 male participants who fulfilled DSM-III-R criteria for alcohol dependence and had no history of interpersonal aggression (ALC) and 10 healthy male participants who did not fulfill criteria for any DSM-III-R axis I diagnosis and had no history of interpersonal aggression (HCS). DV-ALC had a significantly lower mean glucose uptake in the right hypothalamus compared to ALC and HCS. Correlations were performed between measures of glucose utilization in the brain structures involved in fear-induced aggression. The comparison of DV-ALC to HCS and to ALC differed in six and seven comparisons, respectively, involving various cortical and subcortical structures. HCS and ALC differed between the left thalamus and the left posterior orbitofrontal cortex. These PET findings show that some perpetrators of domestic violence differ from control participants in showing lower metabolism in the right hypothalamus and decreased correlations between cortical and subcortical brain structures. A possible psychological covariate of these changes in regional activity might be fear-induced aggression, but this hypothesis should be examined in larger study groups that undergo provocation during imaging.

Adult↗
PubMed2004

Effects of very low birthweight on brain structure in adulthood.

Very-low-birthweight (VLBW) individuals are at high risk of brain injury in the perinatal period. We wished to determine how such early brain lesions affect brain structure in adulthood. Thirty-two VLBW adults (20 female, 12 male) and 18 term, normal birthweight sibling control individuals (nine female, nine male) underwent structural MRI at a mean age of 23 years 4 months (range 17 to 33 years; SD 3.4). Images were analyzed using an automated tissue segmentation algorithm in order to estimate whole brain tissue class volumes in native space. Images were then warped to a template image in standard space. There was no significant between-group difference in whole brain, grey matter, white matter, or total cerebral spinal fluid (CSF) volumes. However, lateral ventricular volume was significantly increased by 41% in those with VLBW. The ratio of grey to white matter was also significantly increased (by 10%) in those with VLBW. Group comparison maps showed widespread changes in the distribution of grey and white matter, and relative excess of ventricular CSF, in the brains of VLBW individuals. Increased ventricular volume predicted decreased grey matter in subcortical nuclei and limbic cortical structures, and decreased periventricular white matter. We conclude that these diffuse abnormalities of grey and white matter are a consequence of the interaction of perinatal brain injury and ongoing neurodevelopmental processes.

Adolescent↗
PubMed2002

Relationship between brain structure and saccadic eye movements in healthy humans.

This study used structural magnetic resonance imaging (MRI) to investigate associations between brain structure and saccadic eye movements. Seventeen healthy subjects underwent structural MRI and infra-red oculographic assessment of a reflexive saccade task. Volumes of prefrontal, premotor, and occipitoparietal cortex, caudate, thalamus, and cerebellar vermis were used as predictors in multiple regression with prosaccade gain as a dependent variable, controlling for whole-brain volume. Using voxel-based morphometry (VBM), gain was entered into correlational analysis with grey matter density. Regression analysis indicated that vermis volumes predicted prosaccade gain. VBM replicated this finding: gain was correlated with grey matter in the left cerebellar hemisphere and vermis. These findings agree with previous studies on the role of the cerebellar vermis in saccadic gain and support the validity of structural neuroimaging methods in elucidating the neural correlates of saccadic eye movements.

Adult↗
PubMed1976

[Anatomic correlation between several cortical and subcortical brain structures].

Investigation of frontal brain sections of 10 cats, 30 dogs and 20 people revealed a topographic correlation between certain cortical and subcortical structures: the beginning of fissura. Sylvii (the so-called "fossa Sylvii") and commissura alba cerebri anterior are located always in the same stereotaxic frontal plane. A method of practical application of the revealed topographic correlation is suggested for the stereotaxic operations on higher animals and human beings.

Animals↗
PubMed2003

Delineation of brain structures from positron emission tomography images with deformable models.

Segmentation of positron emission tomography (PET) images is a difficult task. In this study, we propose a new method for delineation of brain structures according to the tracer uptake. The method is based on a new deformable model which is particularly designed for extracting surfaces automatically from noisy images. The automation is achieved by using a global optimization algorithm for minimizing the energy of the deformable model. As an example, the coarse cortical structure was extracted from FDG PET brain images by delineating first the brain surface and then the white matter surface. We have tested the method with the image of the brain phantom and images from a small number (N = 17) of FDG brain studies. The cortical structure was automatically and reliably found from all the images. The proposed method provides new opportunities for automatic and repeatable structure extraction applicable for regional quantification of the tracer uptake.

Brain↗
PubMed1990

Structural brain abnormalities in bipolar affective disorder. Ventricular enlargement and focal signal hyperintensities.

Structural brain abnormalities were examined in a sample of 48 patients with bipolar affective disorder who were compared with 54 schizophrenic patients and 47 normal controls. As in our previous work using computed tomographic scanning, lateral ventricular enlargement was due to a diagnostic effect. In this study, the effect was more prominent in the schizophrenic men, while a trend was seen in the bipolar men. Women in both groups did not differ significantly from normal subjects. This finding is possibly consistent with the fact that men have a higher frequency of birth anomalies such as hydrocephalus. Since one cause of such birth anomalies might be periventricular hemorrhage or infarction, we also evaluated all scans for the presence of small focal regions of signal hyperintensity. A significant increase in the number of focal signal hyperintensities was noted in the bipolar patients, in comparison with normal subjects, but not in the schizophrenics. The bipolar patients with focal signal hyperintensities had a trend toward larger ventricular size than those without. The pathophysiological significance of these findings is unclear.

Adult↗
PubMed1997

Alcohol consumption alters monoamine oxidase activities in brain structures: relation to ethanol craving.

BACKGROUND: In spite of numerous biochemical studies the role of brain monoamine oxidase (MAO, EC 1.4, 3.4) in the mechanisms of central alcohol action and the pathogenesis of alcoholism remains unclear. The possible reason of that is the highly heterogeneous distribution of the enzyme in a brain and the different direction of alcohol-induced changes of MAO in various morphological structures. Therefore we used the histochemical approach for examination of the effect of chronic alcohol consumption on MAO A and B activities in definite brain structures: various types of aminergic neurons, glial cells and blood capillaries. METHODS AND RESULTS: For 6 months 180 inbred male rats consumed 15% ethanol as the only source of drinking (mean alcohol consumption was 6 g/kg/day). On the 5-6th months of the experiment animals with maximal (ethanol preferring, EP) or minimal (water preferring, WP) alcohol craving were chosen by testing for free choice between 15% (v/v) ethanol solution and water (3 times, during 2 days, at 2-week intervals). The animals chosen were sacrificed and brain samples were studied by our quantitative histochemical method (23). It was found, that chronic ethanol consumption induced dramatic disturbances in MAO activities in the brain structures strongly depending on the alcohol preference of animals. The total MAO activity in WP rats decreased or remained unchanged, but in EP rats it dramatically increased, especially in neurons of n. raphe pontis and n. raphe dorsalis (1.198 +/- 0.028 and 1.268 +/- 0.018 units as compared to control values 0.594 +/- 0.008 and 0.804 +/- 0.011 units; p < 0.001). MAO A activity in all brain structures containing both forms of the enzyme was increased, especially in EP rats: up to 3 times in neurons of the n. raphe pontis from 0.134 +/- 0.003 units in control to 0.541 +/- 0.013 units; p < 0.001). At the same time in the neurons containing only MAO A activity (n. olivaris superior and n. subcoeruleus) it significantly decreased, especially in WP animals. MAO B activity was reduced in the brain structures of WP rats, but activated or unchanged in EP rats. In all the structures studied the MAO B activity was significantly higher in EP, as compared to WP animals (f.e. in astrocytes: 0.314 +/- 0.012 and 0.200 +/- 0.012 units accordingly, p < 0.001). Despite the significant differences in the degree and direction of the changes in the activity of the MAO forms in rats with different alcohol craving, the calculated share of MAO A in the total MAO activity was regularly increased in all structures studied both in EP and WP animals; the share of MAO B activity accordingly decreased. CONCLUSIONS: Chronic alcohol consumption induces the great disturbances in brain MAO activity and isozyme composition following chronic ethanol consumption, strongly depending of the alcohol craving of the animals. It indicates the involvement of the enzyme in the mechanisms of central alcohol action.

Alcoholism↗
PubMed1989

[Lipid peroxidation in the synaptosomal and mitochondrial fractions of separate brain structures in hypoxia].

The paper studies intensification of lipid peroxide oxidation in separate brain structures (the medulla oblongata, cerebellum, visual and sensomotor cortex), synaptosomal and mitochondrial fractions under hypoxia. It has been established that acute hypoxia increases accumulation of lipid peroxidation (LPO) products, hydroperoxide and malonyl dialdehyde. Intensification of LPO in synaptosomes and mitochondria is more pronounced as compared to the whole structures. Preliminary treatment with antioxidants (vitamin E and ionol) considerably suppressed LPO intensity under both hypoxia and hypoxia with reoxygenation. Intensification of LPO in synaptosomes and mitochondria is suggested to be the key point in structural-functional disturbances of the nervous system under hypoxia and ischemia.

Acute Disease↗