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Multiple sclerosis (MS) is a neurodegenerative disease characterised by inflammation and demyelination. It generates irreversible myelin changes, which in turn give rise to physical and cognitive disorders. The verbal fluency test (VF) has been shown to be a sensitive tool for detecting cognitive impairment in these patients. Objective: To compare quantitative and qualitative aspects of performance on semantic and phonological fluency tests between MS patients and healthy controls by analysing total words produced and strategies used (clusters and switching). Method: We evaluated 46 patients with MS and 33 healthy controls using the VF test. Results: The semantic VF task revealed no significant differences between groups; for the phonological task, the patients demonstrated reduced word production (F [77] = 2.286 P

Resumen: La esclerosis múltiple (EM) es un padecimiento neurodegenerativo caracterizado por inflamación y desmielinización y que conduce a un cambio irreversible de la mielina, lo que conlleva a la presencia de alteraciones físicas y cognitivas. La prueba de fluidez verbal (FV) ha demostrado ser sensible para evidenciar deterioro cognitivo en estos pacientes. Objetivo: Comparar aspectos cuantitativos y cualitativos del desempeño en pruebas de fluidez semántica y fonológica en pacientes con EM y sujetos sanos, mediante el análisis del total de palabras producidas y de las estrategias utilizadas (agrupaciones y saltos). Método: Se evaluaron 46 pacientes con EM y 33 sujetos sanos mediante la prueba de FV. Resultados: En la FV semántica no hubo diferencia estadística entre los grupos. En la FV fonológica los pacientes presentaron menor producción de palabras (F [77] = 2.286; p

The burden of chronic disease in Europe continues to grow. A major challenge facing national governments is how to tackle the risk factors of sedentary lifestyle, alcohol abuse, smoking, and unhealthy diet. These factors are complex and necessitate intersectoral collaboration to strengthen health promotion, counter-act the social determinants of health, and reduce the prevalence of chronic disease. European countries have diverse intersectoral collaboration to encourage health promotion activities. In the Joint Action CHRODIS-PLUS success factors for intersectoral collaboration within and outside healthcare which strengthen health promotion activities were identified with a mixed method design via a survey of 22 project partners in 14 countries and 2 workshops. In six semi-structured interviews, the mechanisms underlying these success factors were examined. These mechanisms can be very context-specific but do give more insight into how they can be replicated. In this paper, 20 health promotion interventions from national programs in CHRODIS PLUS are explored. This includes community interventions, policy actions, integrated approaches, capacity building, and training activities. The interventions involved collaboration across three to more than six sectors. The conclusion is a set of seven recommendations that are considered to be essential for fostering intersectoral collaboration to improve health-promoting activities.

Background: Structuring cancer care into pathways can reduce variability in clinical practice and improve patient outcomes. International benchmarking can help centers with regard to development, implementation, and evaluation. A further step in the development of multidisciplinary care is to organize care in integrated practice units (IPUs), encompassing the whole pathway and relevant organizational aspects. However, research on this topic is limited. This article describes the development and results of a benchmark tool for cancer care pathways and explores IPU development in cancer centers. Methods: The benchmark tool was developed according to a 13-step benchmarking method and piloted in 7 European cancer centers. Centers provided data and site visits were performed to understand the context in which the cancer center operates and to clarify additional questions. Benchmark data were structured into pathway development and evaluation and assessed against key IPU features. Results: Benchmark results showed that most centers have formalized multidisciplinary pathways and that care teams differed in composition, and found almost 2-fold differences in mammography use efficiency. Suggestions for improvement included positioning pathways formally and structurally evaluating outcomes at a sufficiently high frequency. Based on the benchmark, 3 centers indicating that they had a breast cancer IPU were scored differently on implementation. Overall, we found that centers in Europe are in various stages of development of pathways and IPUs, ranging from an informal pathway structure to a full IPU-type of organization. Conclusions: A benchmark tool for care pathways was successfully developed and tested, and is available in an open format. Our tool allows for the assessment of pathway organization and can be used to assess the status of IPU development. Opportunities for improvement were identified regarding the organization of care pathways and the development toward IPUs. Three centers are in varying degrees of implementation and can be characterized as breast cancer IPUs. Organizing cancer care in an IPU could yield multiple performance improvements., (Copyright © 2018 by the National Comprehensive Cancer Network.)

Unlabelled: Multiple sclerosis (MS) is a neurodegenerative disease characterised by inflammation and demyelination. It generates irreversible myelin changes, which in turn give rise to physical and cognitive disorders. The verbal fluency test (VF) has been shown to be a sensitive tool for detecting cognitive impairment in these patients., Objective: To compare quantitative and qualitative aspects of performance on semantic and phonological fluency tests between MS patients and healthy controls by analysing total words produced and strategies used (clusters and switching)., Method: We evaluated 46 patients with MS and 33 healthy controls using the VF test., Results: The semantic VF task revealed no significant differences between groups; for the phonological task, patients demonstrated reduced word production (F [77]=2.286 P<.001) and poorer use of grouping strategies, resulting in more frequent switching (F [77]=3.808 P<.005)., Conclusions: These results support using qualitative analysis for recall strategies, since the technique provides data about which components of the task are affected by brain damage. Clusters depend on the integrity of semantic memory, while switching has to do with developing effective search strategies, cognitive flexibility, and the ability to modify responses. Frontal lobe damage has been reported in MS, and this is consistent with results from the phonological VF test., (Copyright © 2012 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.)

Introduction: Some studies have reported that attention-deficit/hyperactivity disorder (ADHD) children show alterations in different cognitive functions. Recently, a deficiency in the executive functions (EF) is proposed as the cause underlying all of these symptoms. However discrepancies exist about these findings., Objective: Assessment of cognitive and executive functions of subjects with both ADHD hyperactive-impulsive type and combined type, in order to reveal their neuropsychological characteristics and analyze if those functions are related to hyperactive-impulsive behavior., Method: Neuropsychological Battery, Stroop test, Wisconsin Card Sorting test and London Tower test were applied to 51 children between 7 and 12 years old (25 controls and 26 ADHD)., Results: ADHD children showed worst performance in sustained attention, rapid serial naming of figures and colors, comprehension of written instructions, word dictation, number comparison, arithmetical problems, visual working memory, long term memory and the scores of WCST. Variables related to hyperactivity-impulsivity were: errors and decreased velocity in rapid serial naming of colors and figures, comprehension of written instructions, arithmetical problems and the scores of total errors, perseverating errors and perseverating responses of WCST., Conclusion: ADHD children show a great variety of cognitive deficiencies and had deficit only in some domains of executive functions. These deficiencies could explain to some extent the hyperactive and impulsive behavior.

In this paper we have made a broadband analysis to detect the electroencephalogram (EEG) frequencies that change selectively during the presentation of normal and "thatcherized" faces. Referential recordings to linked ears were obtained in 21 leads in 48 right-handed healthy male volunteers. Increase of delta power (1.75-3.91 Hz) was observed, related to the detection of distortion in faces at bifrontal and left temporoparietal cortex. The other bands had no contribution, when normal and modified faces were compared. These results support our hypothesis that a change in EEG power spectral may be related to discrimination between normal and thatcherized faces.

Some cognitive abilities of arithmetical calculation depend on retrieval of arithmetic facts from long-term memory. Arithmetic-fact retrieval has been studied in adults through Event-Related Potentials (ERP) experiments. Such information in children, however, has been scarce. It has been reported that from the age of 9 years, children employ a memory retrieval strategy for solving simple multiplication problems. The present study compared arithmetical-fact retrieval in children and adults while they were being subjected to ERP recording. The subjects were asked to make judgments about solutions to simple multiplication problems. Both groups of participants displayed the so-called arithmetic N400 effect for incorrect solutions relative to correct solutions. Adults showed a posterior N400 effect, while children showed a widely distributed N400 effect. Children displayed a larger amplitude and longer latency arithmetic N400 component than adults; this observation could be due to children exerting greater effort involving more widespread cortical activation than adults to solve the experimental problems. The Late Positive Component (LPC), which follows the arithmetic N400 and has been described previously in adult subjects, was observed in the present adult subjects, but was present in children only for correct solutions. These results may indicate that, relative to adults, children showed slower memory retrieval and a different pattern of a verification mechanism for correct and incorrect solutions., (Copyright 2009 Elsevier Ireland Ltd. All rights reserved.)

A source localization analysis was carried out to provide brain functional and structural assessments of individuals with poor reading skills. Standardized low-resolution brain electromagnetic tomography was used to locate sources of P2 and P3 event-related potential components in normal readers and in poor reader children performing a cued continuous performance task. Cue-elicited P2 sources in the right superior parietal gyrus were smaller in 37 poor readers than in 40 normal readers. Poor readers showed a higher P3 activation in response to a false target in frontal and frontorbital regions than normal readers. These results suggest that reading disabilities may be attributed to failures in attentional focalization for incoming stimuli.

This study explores visual event-related potentials components in a group of poor readers (PRs) and control children who carried out figure and word categorization tasks. In both tasks, every child had to categorize between animal and non-animal stimuli in an odd-ball GO-GO paradigm. During the word categorization task, PRs presented longer reaction times, a poorer performance, longer and larger P2 amplitudes, and smaller amplitudes and longer P300 latencies than controls. There were no differences in the N400 component between groups. These results suggest that semantic processing underachievement in PRs may not be a semantic deficit per se, but the late reflection of an early word codification problem, deficient use of attentional resources and lack of target identification during reading.

The objective of this study was to discover how narrow-band spectral measurements express emotional behavior. Electroencephalographic narrowband absolute and relative spectral powers were calculated for every 1 Hz of frequency from the recordings of 40 healthy male university students during emotional tasks. Sentences evoking positive, negative, and neutral emotional states were used as stimuli. Repeated multivariate analyses of variance were computed with IQ as covariate. The results showed only a few significant relations between absolute power and emotion. Relative power reflected better the differences determined by emotional states. The frequencies between 7.6 and 9.5 Hz showed differences between emotional states over the entire scalp with increased power during neutral state. Interaction between emotional states and cerebral regions revealed that all cerebral areas had an important role, especially frontal, parietal, and temporal regions. Hemispheric differences showed less power in the left hemisphere during positive emotional state (joy of love) in the 8.6 to 9.5 Hz band and in the right hemisphere during negative emotional state (frustration) in the 17.6 to 18.5 Hz band. Significant interaction between states, hemispheres, and electrode positions was observed in the frequency range of 17.6 to 19.5 Hz. As none of our results covered the range of any broad band, we may conclude that narrow-band calculations are more adequate for the study of emotions, because their use reduces the danger that frequency-specific effects go undetected or cancel each other.

The P300 ERP component was studied in poor and normal readers, using Sternberg and color discrimination (Spaceships) tasks. During the first one, subjects must decide if a probe item belongs or not to a set of digits previously presented. In the second one, the participants must shoot violet spaceships with one key and other than violet spaceships with another key. There were no significant differences between groups with respect to reaction times, but a larger proportion of errors was observed in poor readers. Longer P300 latencies were recorded for poor readers than controls in both tasks. P300 amplitudes showed topographical differences between the two groups: Poor readers' P300 is larger frontally during the Sternberg task, but smaller at posterior sites during the Spaceships task. These results suggest that poor readers may have deficiencies during the early processing stage, such as visual stimulus evaluation. Poor readers also appear to have deficits for classifying and memorizing visual stimuli.

Broad band spectral measurements were calculated on EEG recordings of 40 healthy male university students during emotional tasks using the emotion induction technique. Emotional stimuli were sentences with positive valence (joy of love), with negative valence (frustration) and neutral situation. Broad band measurements showed that delta and beta bands reflected better the differences by emotional state. Hemispheric differences associated to emotional states were obtained only for mean frequency data. Higher delta frequencies at left frontopolar, right frontal, parietal and temporal and higher beta frequencies at left frontotemporal and temporal were related to love. Meanwhile higher delta frequencies especially at left frontopolar and temporal regions and lower beta frequencies at midline frontal (Fz) and central (Cz) leads were associated to frustration. These findings suggest that narrow band measurements may reflect more efficiently EEG changes during emotional tasks.

In this study it was shown that in adults, the frequency characteristics of EEG preceding stimuli that were followed by incorrect responses were different from the characteristics of EEG preceding stimuli that were followed by correct responses. In the recording during three different tasks that explore different neuronal networks, higher values of current preceding incorrect performance in those areas directly related to the task were found in frequencies within the delta (1.56 and 3.12 Hz) and beta bands (13.26, 14.04, 14.82, 15.6, 17.16 and 17.94 Hz), suggesting that these frequencies signal inhibition. Frequencies within the alpha band (9.36 and 12.48 Hz) showed greater energy preceding correct responses in task-specific areas, supporting previous results observed in children.

Although poor readers (PR) are considered the major group among reading-disabled children, there are not event-related potentials (ERP) studies reported of PR on the subject. In this study, attentional and memory processes were studied in an auditory oddball task in PR and normal controls. ERP to auditory stimuli were recorded in 19 leads of the 10/20 system, using linked earlobes as references, in 20 normal children (10 female) and 20 PR (10 female) of the same age (10-12 years old). Two pure tones (1000 and 3000 Hz) were used in an oddball paradigm. No significant differences were observed in the amplitudes and latencies of N100 between the groups. However, N200 to frequent stimuli and P200 to both frequent and infrequent stimuli were of higher amplitude in poor readers than in normal children. There were no differences between groups in the latency and amplitude of P300. The results suggest that PR use more attentional resources in the components occurring before P300 to both frequent and infrequent stimuli than the normal children, and this finding is particularly marked for PR girls.

Auditory event-related brain potentials (ERPs) were recorded from 10 subjects in two different conditions: (1) subjects were required to reorder five visually presented letters in order to form a word and provide a verbal response (task condition); (2) subjects were presented with a control stimulus with the same physical characteristics as the experimental stimulus, but containing just one type of letter (i.e., AAAAA). Subjects had to verbally respond to such stimuli by saying "A" (control condition). Tones of 1000 Hz (standard) and 1050 Hz (deviant) were also presented to the subjects in a 85%-15% probability paradigm 2 s before, during and 8 s after the presentation of the visual stimuli. Recordings were obtained from Fpz, Fz, Cz and Pz vs. linked ears. Auditory ERPs to the auditory stimuli after the presentation of the visual letter string and during the performance of the task were averaged for the standard and deviant tones in both conditions. Only correct responses were considered for the averages. The N100 was affected by stimulus type (standard vs. deviant) but not by condition (task vs. control); however, larger P3a waves were observed during the control than during the task condition. No significant differences between conditions were observed in the mismatch negativity (MMN) latency range. These results suggest that primary task demands modulate involuntary attention processing.

Objective: To investigate whether the N400 effect is sensitive to automatic or controlled processes., Methods: Two experiments were performed. In one experiment, directly related word pairs were used. In the other experiment, mediated-related word pairs were used. In order to reduce controlled processes, each experiment consisted of 3 tasks: Low- and high-proportion of related pairs, and single presentation lexical decision task., Results: In the first experiment, the amount of priming was equivalent for the 3 tasks. The N400 effect appeared in the high and low proportion of directly related words, but not in the single presentation task. In the second experiment, behavioral priming was also found in the 3 tasks. However, the N400 effect was observed only in the task with low proportion of related pairs., Conclusion: These results suggest that the N400 effect may be related to controlled processes.

In routine clinical EEG, a common origin is assumed for delta and theta rhythms produced by brain lesions. In previous papers, we have provided some experimental support, based on High Resolution qEEG and dipole fitting in the frequency domain, for the hypothesis that delta and theta spectral power have independent origins related to lesion and edema respectively. This paper describes the results obtained with Frequency Domain VARETA (FD-VARETA) in a group of 13 patients with cortical space-occupying lesions, in order to: 1) Test the accuracy of FD-VARETA for the localization of brain lesions, and 2) To provide further support for the independent origin of delta and theta components. FD VARETA is a distributed inverse solution, constrained by the Montreal Neurological Institute probabilistic atlas that estimates the spectra of EEG sources. In all patients, logarithmic transformed source spectra were compared with age-matched normative values, defining the Z source spectrum. Maximum Z values were found in 10 patients within the delta band (1.56 to 3.12 Hz); the spatial extent of these sources in the atlas corresponded with the location of the tumors in the CT. In 2 patients with small metastases and large volumes of edema and in a patient showing only edema, maximum Z values were found between 4.29 and 5.12 Hz. The spatial extent of the sources at these frequencies was within the volume of the edema in the CT. These results provided strong support to the hypothesis that both delta and theta abnormal EEG activities are the counterparts of two different pathophysiological processes.

The relationship of IQ (measured by WAIS and all its subscales) and EEG broad band spectral parameters were studied in 40 right-handed, male volunteers ranging in age from 20 to 25 years old. EEGs were recorded in 20 derivations during rest with eyes opened. The results obtained reveal positive and negative correlations with abundant frontal participation in all bands. Mean frequency data show a frequency shift in a very narrow range suggesting that more relations in narrow band could be achieved. These results highlight the need of psychological tests that measure more homogeneous abilities and finer measurement technique to reveal clearly explainable correlations and demonstrate that EEG recordings do reflect intellectual abilities.

This study shows that incorrect responses are preceded by different EEG characteristics than correct responses, and that these differences appear in specific brain regions that participate in each particular task. EEGs were recorded in children during three different tasks: color discrimination (CDT), verbal working memory (VWM), and word categorization task (WCT). EEG segments previous to the presentation of the stimulus were analysed. Incorrect responses were preceded by lower EEG power values at 7.8 Hz in posterior temporal and right parietal leads in CDT, 8.59 and 9.36 Hz in frontal areas in VWM, and 10.72 Hz in the left hemisphere in WCT. In the former task > 1.56 Hz power in frontal areas prior to an incorrect response was also observed.

A follow-up study on EEG coherence values was carried out with 46 school-age children divided into three pedagogical groups considering their reading and writing abilities (normal subject and children with mild and with serious reading-writing problems). EEGs were recorded at rest, with eyes closed in 15 referential derivations that gave 105 possible coherence values. Coherence was calculated after the elimination of the average reference. Repeated Measure ANOVAs were calculated to evaluate the effects of time, sex, reading-writing problems and their interactions. The second EEG recordings were taken 2-3 years after the first. The results revealed significant increase of coherence values during the time lapse studied, consisting of an increase of frontal coherences in all bands, with the exception of the theta band. The most numerous changes occurred in the alpha band. Very few differences in coherence values were observed between the two EEG recordings by pedagogical groups and by sex suggesting a similar but not igual maturation of coherences of boys and girls and of the three pedagogical groups, in this age range studied. These findings suggests an abnormal coherence development for the reading disabled group, as well as different coherence maturation for boys and girls in this time lapse studied.

In previous papers we have proposed that in patients with space-occupying lesions, delta power was related with the volume of the lesion and theta power with the volume of the edema. In this report we analyze the evolution of 10 patients with space-occupying lesions in whom we measured the volume of the lesion and of the edema before and after treatment that produced changes in these volumes. EEGs were recorded in the leads of the 10-20 system referenced to linked earlobes. Delta and theta powers were calculated for voltage and current source densities (CSD) and compared with age-norms to compute conventional Z-maps. These maps provide probability statements about the deviation of observed values from the norm. Rank correlations between the change in the volume of the lesion before and after treatment and the change in Z-values before and after treatment were significant only in the delta band. However, rank correlations between the change in the volume of the edema and the change in EEG Z-values were only significant in the theta band. These correlations were higher for CSD than for voltage estimates. We also observed that the site of the lesion and of the edema was better represented by CSD maps than by voltage maps. These results are also in agreement with our previous reports, in which we observed more precise localization of brain lesions by CSD than by voltage estimates.

In vitro testing of lipase survival of Panzytrat 25,000 homogenized in Tris HCl buffer and Lundh meal stimulated gastric or duodenal contents demonstrated favorable stability of lipase of this new preparation in the protein and fat containing gastric and duodenal juices of patients with chronic pancreatitis. Later an open, intra-individually controlled study with two doses of Panzytrat 25000 (5 x 1 and 5 x 2 capsules/day) was performed in 10 patients with severe pancreatic steatorrhoea. A diet containing 70 g of fat/day was offered and the 3-day fat loss of collected stools was measured in the last 3 days of 5-day equilibration periods with and without replacement therapy. After these short-term periods, patients were treated with 5 x 1 capsules of the drug for one month and body weight increases as well as patient's appraisals were registered. Stool weight and fat loss maximally decreased already in response to the 5-day treatment with 5 x 1 capsules of drug and double dose of the preparation did not further decrease steatorrhoea in most cases except 2 patient. Disappearance of fat loss was achieved in 3 out of ten patients. Body weight of patients increased in most cases and their subjective evaluation was also favorable.

In previous papers we proposed that an increase in delta EEG activity during mental tasks might be related to an increase in subjects' attention to internal processing. In this paper we have made a narrow band analysis to detect those EEG frequencies that change selectively during the performance of a mental task that requires attention to internal processing. Two different experiments were performed: (1) a difficult mental calculation task and a control stimulus with the same physical characteristics as the arithmetical symbols were presented in random order; (2) the Sternberg paradigm for the analysis of short term memory using a memory set of 5 or 3 digits was also presented in random order. Referential recordings to linked ears were obtained in all leads of the 10/20 system. In the first experiment, the increase of power from 1.56 to 5.46 Hz was observed only during the performance of the task and not during the control condition. In the Sternberg paradigm, the increase of power from 1.56 to 3.90 Hz was greater during the difficult than during the easy condition. These results support our hypothesis that an increase in delta activity may be related to attention to internal processing during the performance of a mental task.

The effect of prostaglandin E1 (PGE1) on the severity of acute pancreatitis induced by a closed duodenal loop in the rat was tested. PGE1 was administered subcutaneously at various doses (3, 6, 12, and 24 microgram/kg) at hourly intervals, from the induction of acute pancreatitis up to the 24th hour. A saline-treated group served as the control. The mortality rate was recorded, and pancreatic histology was evaluated by a scoring system. Serum amylase activity and pancreatic amylase, trypsin, protein, and desoxyribonucleic acid (DNA) contents were determined at 24 h. Administration of PGE1 influenced the severity of acute pancreatitis biphasically. Serum amylase was reduced significantly (p < 0.01) at a dose of 12 microgram/kg/h, but less at 24 microgram/kg/h. Pancreatic weights did not differ in the groups. Pancreatic amylase, trypsin, and protein contents showed significant elevations (p < 0.01), yet the mortality rate was reduced using 6 and 12 microgram/kg/h doses of PGE1 compared to controls, but not at higher and lower doses. The DNA content was significantly higher at the 6 microgram/kg/h dose, compared to the control. The extent of necrosis and the severity of hemorrhage were reduced significantly (p < 0.05) at doses of 6 and 12 microgram/kg/h of PGE1, but less at 24 microgram/kg/h. Leukocyte infiltration was not affected. In conclusion, optimal doses of PGE1 can ameliorate, but higher doses increase, the severity of acute pancreatitis in this experimental model.

In a previous study (Harmony et al. 1993) we observed that the volume of lesions was correlated only with delta power, while the volume and density of edema showed a significant correlation with theta and alpha power, suggesting two independent origins of activity in the delta and theta bands in patients with space-occupying lesions. Our goal in this paper is to show, through a different technique, in a narrow band spectral analysis, that brain lesions are characterized by activity in the delta domain and that edema is better correlated with activity within the theta range. Frequency source analysis based on the Maximum Likelihood (ML) test for rejection of isotropicity was applied to the EEG at rest of 36 patients with space-occupying intracranial lesions. The ML test was rejected at frequencies below 1 Hz and in the low range of the delta rhythm in 31 patients. The origin of the equivalent dipoles at these frequencies was within the volume of the lesion in 27 patients. In 15 patients out of 19 with vasogenic edema the ML test was rejected at frequencies in the theta range. The equivalent dipoles at these frequencies were all within the volume of the edema.

In a previous paper, using the same test for the evaluation of reading-writing abilities, Harmony et al. (1990b) reported that children with severe difficulties had more delta in fronto-temporal regions, and this was interpreted as a sign of underlying cerebral dysfunction. Children with severe and minor difficulties in the test had more diffuse theta absolute and relative powers and less alpha relative power. As theta decreases with age, while alpha increases, these results suggested that children with minor and severe difficulties in reading had a maturational lag with respect to those with normal performance. We conducted this study in order to test this hypothesis. Two different EEG records were obtained with an interval of 2.58-3.15 years in 49 children classified in 3 groups according to their performance in a reading-writing test. Group 1: adequate performance for age and degree (control group); group 2: below level performance with minor difficulties; and group 3: below level performance, with severe difficulties. The mean age of the groups in the first study was 9 years. Absolute (AP) and relative powers (RP) in the delta, theta, alpha and beta bands were computed for each session. In general, groups 3 and 2 showed greater changes than group 1 from session to session. ANOVAs performed by session clearly demonstrate many significant differences between groups in the first study, while few significant differences in parieto-occipital regions in theta RP were observed in the second session. These results point toward a maturational spurt of children from groups 2 and 3.

Conventional Z maps provide probability statements about the deviation of observed values from the norm. Galán et al. (1994) introduced Simultaneous Significance Probability Scales to detect abnormalities over the whole map, making use of the information provided by the topographic structure of dependencies. They also described multivariate brain electromagnetic (MBE) maps for compact presentation of complex spatio-temporal information. In this paper, using the distance-based localization receiver operating characteristic curves (DL-ROC curves), we compare the localization provided by computed tomography with that provided by Z and MBE maps in 61 patients with brain lesions. Maps were calculated for absolute power and relative power in delta, theta, alpha and beta bands for voltage and current source densities (CSD). In each patient, all maps were compared and the map with the highest value of the area of the DL-ROC curve was considered to be the "best map." Z maps of CSD were the "best maps" in 24 patients. In the voltage montage, we observed that multivariate maps add some information not contained in the Z maps. However, for CSD, Z maps were more accurate than multivariate maps. A very consistent finding was the observation that lesions were better detected by maps analyzing the delta band, while edema was better represented by maps in the theta range.

In this study we demonstrate the existence of different patterns of EEG activation during the performance of 4 different tasks involving different components of mental calculation in normal subjects. The EEG was recorded in all monopolar leads of the 10/20 system using linked ear lobes as reference. Absolute and relative power were calculated in the delta (1.5-3.5 Hz), theta (3.5-7.5 Hz), alpha (7.5-12.5 Hz) and beta (12.5-19 Hz) bands. The tasks were presented randomly and the EEG segments preceding presentation of the stimulus were considered as the rest corresponding to the task requested by the stimulus. Tasks were of 4 different types, involving number comprehension, recognition of mathematical symbols, the calculation process and the spatial component. ANOVAs between the rest periods showed no differences in any band. Neither did ANOVAs between tasks. However, other variables (task minus rest), which were calculated as the differences in power between task and rest respectively, showed significant differences between tasks in the delta and beta bands in the frontal lobes. In addition, new variables were calculated as the difference between tasks, since many factors were common across several tasks. These variables correspond to the EEG change due to a specific component of mental calculation. Significant differences were obtained in delta and theta bands in right posterior areas and in the beta band in frontal areas. We concluded that the EEG differences observed during different components of mental calculation suggest the participation of different networks.

The relationship of reading-writing ability and EEG coherences was studied in 84 subjects from two age groups 7.0-8.9 and 9-11.2 years old. All children were divided into three groups according to their performance on a pedagogical test: ped1, normal children; ped2, children with mild problems; ped3, children with reading-writing disability. The following results were obtained: in general, children showed higher coherences in groups with poor performance in the delta, theta and beta bands. In the alpha band, higher coherence values were related to better performance. The exceptions to this general pattern were rare. Group ped2 had higher coherences in delta, theta and alpha bands than ped1 and ped3, in left temporal leads. In older children the same tendency was observed, but group differences in the theta, alpha and beta bands were few. In this age range, the significant group differences were almost all interhemispheric coherences. The discriminant analysis that classified subjects by their coherence values gave very good results, fact that demonstrates, that EEG coherence is a highly sensitive measurement indicating not only the existence of a reading-writing problem, but also the degree of its severity.

The aim of this work was to study in rats the temporal course of laboratory parameters and morphologic features in acute pancreatitis induced by cholecystokinin octapeptide (CCK-8) or by a closed duodenal loop. Pancreatitis was induced either with an overdose of CCK-8 (3 x 75 micrograms/kg at 1 h intervals) or by ligation of the duodenum on both sides of the bilio-pancreatic duct. The animals were examined at 0, 2, 4, 8, 16 and 24 h after AP induction. In CCK-8-induced acute pancreatitis, the pancreatic weight/body weight ratio (8.2 +/- 1.1 mg/g) and the amylase level (44.8 +/- 7.5 x 10(3) U/ml) were significantly increased vs. the controls (4.5 +/- 0.8 mg/g and 3.3 +/- 0.2 x 10(3) U/ml, respectively) 2 h after the intervention. The plasma CCK was significantly increased at 4 h (4.55 +/- 1.7 pM) and remained elevated thereafter. The tissue malonyldialdehyde concentration was significantly elevated at 8 h (0.28 +/- 0.07 mumol/mg pancreas) vs. the controls (0.20 +/- 0.02 mumol/mg pancreas). In closed duodenal loop-induced acute pancreatitis, the ratio pancreatic weight/body weight steadily increased during the study; it reached its maximum level at 24 h (7.1 +/- 0.5 mg/g) vs. the sham-operated control (4.8 +/- 0.9 mg/g). The serum amylase level was significantly elevated at 2 h (47.1 +/- 9.3 x 10(3) U/ml), and then decreased steadily. Plasma CCK values were significantly higher than the controls throughout the study. A significant increase in the tissue malonyldialdehyde concentration (0.94 +/- 0.15 mumol/mg vs. 0.20 +/- 0.01 mumol/mg pancreas) appeared at 4 h. Our data indicate that in CCK-8-induced acute pancreatitis the laboratory signs of pancreatitis are most expressed at 4 h, whereas the morphologic changes culminate 8 h, following the last CCK injection. In closed duodenal loop-induced acute pancreatitis, the histologic findings showed a progressive deterioration. Endogenous CCK and oxygen-derived free radicals seem to play a role in the pathogenesis of both types of acute pancreatitis.

EEG coherence between all pairwise combinations of the 10/20 system was studied in two groups: control subjects and patients with space-occupying brain lesions. Coherence was separately computed for the delta, theta, alpha and beta bands. Comparisons between both groups showed highly significant differences in all bands. In the patients with lower coherence values, these differences were mainly in the alpha band. When intra-hemispheric coherences between controls and patients with left hemispheric lesions were compared, significant differences were observed only in the left hemisphere. Comparisons between controls and patients with lesions in the right hemisphere also showed significant differences only in the injured hemisphere. In patients, paired t tests between the values of the intra-hemispheric coherence in the left hemisphere and the corresponding values in the right hemisphere demonstrated that lower coherences were confined to the damaged hemisphere. Our conclusion is that in the presence of lesions disrupting cortex and adjacent white matter the coherence between this area and the remaining cortical areas is lower than normal due to impairment of the fibers that connect the damaged area with the rest of the brain.

In a group of patients with space-occupying brain lesions, CT measurements were correlated with absolute power (AP) and relative power (RP) of the delta, theta, alpha and beta EEG bands, calculated from the raw EEG potentials (EEGp) and from the Laplacian estimates also called "current source densities" (CSD). Rank correlations were calculated between the number of abnormal values in each band and the following CT measures: volume of the lesion and of the edema, density of the edema, percentage of ventricular collapse and midline shift. Abnormal spectral values are those which are significantly higher than the norm for the same age, in the delta and theta bands, and significantly lower in the alpha and beta bands. Spectral parameters obtained from the CSD showed higher correlations with CT measures than those calculated from the EEGp. In the Laplacian, all CT measures had a significant correlation with delta AP. Theta AP was significantly correlated with the volume and density of the edema, as well as with midline shift. Significant correlations were also observed with delta and alpha RP. However, changes in RP were considered to be a consequence of the increase in delta AP. Canonical correlation analyses between AP and RP calculated from EEGp or CSD and the first 3 CT measures showed that the volume of the lesion was only correlated with delta AP and RP. The volume and density of the edema showed a significant correlation with delta, theta and alpha AP calculated from EEGp and only with theta and alpha AP in the Laplacian. Since the EEGp tends to produce a more extensive and diffuse picture of abnormality, whereas the Laplacian acts as a spatial filter emphasizing local sources over distant sources, we concluded that edema is related not to delta activity, but to the theta and alpha power.

The idea that sex differences in the execution of different mental tasks mean a different cerebral organization met contradictory results. Sex differences in brain electrical activity were reported by various authors. The EEG coherences show functional and anatomical interrelation, so they may reveal differences in brain organization. This paper tries to demonstrate how sex differences are manifested in EEG coherences, in 42 right-handed control children, 18 girls and 24 boys, aged 7.6 to 13.3. Since the effect of age is high on EEG measurements, regression against age was calculated and eliminated. The Z-transformed coherence values were compared by Student's t-test. The results obtained showed that girls had higher right intrahemispheric coherence values than boys in all bands. These sex differences were more numerous in the theta band. The interhemispheric differences were slight and girls had higher coherences in all bands except for the alpha band, where boys had higher interhemispheric coherence than girls. These results show slight but consistent differences in the functional organization of the right hemisphere by sex and reveal the necessity to elaborate separated EEG norms for boys and girls.

We analyzed test-retest reliability of Absolute (AP) and Relative Power (RP) during rest and during two cognitive tasks: one verbal, the search for a synonym, and the other consisting of mental arithmetic calculations. Under all conditions during the experiment the subjects had their eyes open. The experiment was performed twice, with a month's interval between each trial. Monopolar recordings were obtained in F3, F4, C3, C4, P3, P4, O1, O2, F7, F8, T3, T4, T5, T6 and Cz vs A1A2. Differences between sessions were observed mainly during rest with eyes open in the lapha band, with higher AP during the first session. During rest it is extremely difficult to control for the state of vigilance, anxiety and thinking. However, during cognitive tasks a more rigid control of the state of vigilance and thinking is obtained. Therefore, AP and RP are very reliable parameters for analyzing EEG during mental tasks. Comparisons between conditions were also made. The only significant differences observed were in delta AP in the second session, with more power during the cognitive tasks in C3 and O2. MANOVAs using the values of AP in the four bands showed significant differences between conditions in C3, C4, P3, O2 and T4. Several factors that may be involved in the origin of delta activity, including eye movements, slow potential shifts and the inhibition of cholinergic projections to the cortex, are discussed.