bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hippocampal Atrophy Is Not a Major Determinant of Regional Hypometabolism in Temporal Lobe Epilepsy
Authors: O'Brien T. J. , Newton M. R. , Cook M. J. , Berlangieri S. U. , Kilpatrick C. , Morris K. , Berkovic S. F. 
Published: August 2005

Summary: Purpose: The pathophysiologic basis for the [18F]fluorodeoxyglucose positron‐emission tomography (FDG‐PET) temporal lobe hypometabolism in patients with hippocampal sclerosis (HS) is uncertain. We tested the hypothesis that hippocampal atrophy, which is strongly correlated with hippocampal cell loss, is largely responsible for the regional hypometabolism in HS. Methods: Regions of interest (ROIs) on FDG‐PET scanning were determined in the medial, lateral, and posterior temporal lobe, thalamus, and basal ganglia. A right/left asymmetry index for each ROI was calculated. These results were correlated with hippocampal magnetic resonance imaging (MRI) volume ratios. Results: There was no correlation between the magnitudes of the FDG‐PET asymmetry index and the MRI volume ratio for the mesial or lateral temporal regions (r =−0.09, r =−0.04). When the right/left asymmetry index was compared with the right/left hippocampal volume ratio, correlations for the mesial temporal ROI (r = 0.79, p < 0.0001) and lateral temporal ROI (r = 0.57, p < 0.0005) were found. These, however, simply indicated that both tests accurately reflect the side of the epileptogenic region. The concordance of the side of relative hypometabolism of the FDG‐PET with the side of the hippocampal atrophy was higher for the mesial temporal region (100%) than for the lateral (77.5%). Conclusions: The lack of correlation between the magnitudes of the ratios argues against hippocampal atrophy and cell loss having a central role in the FDG‐PET temporal hypometabolism.
FDG‐Positron Emission Tomography and Invasive EEG: Seizure Focus Detection and Surgical Outcome
Authors: Theodore William H. , Sato Susumu , Kufta Conrad V. , Gaillard William D. , Kelley Kathy 
Published: August 2005

Summary: Purpose: To study the value of [18F]2‐deoxyglucose (FDG)‐positron emission tomography when surface ictal EEG is nonlocalizing. Methods: FDG‐PET scans were performed in 46 patients with complex partial seizures (CPS) not localized by ictal SUT‐face‐sphenoidal video‐EEG (VEEG) telemetry. Interictal PET was performed with continuous EEG monitoring, and images were analyzed with a standard template. Forty patients subsequently had subdural and 6 had depth electrodes (invasive EEG, IEEG); 22 had bilateral implants. A focus was detected in 40, and 35 had temporal lobectomy based on IEEG localization. Results: There was a close association between IEEG and PET localization (p < 0.01): 26 patients had relative unilateral temporal FDG‐PET hypometabolism, all had congruent IEEG, and 18 of 23 were seizure‐free after temporal lobectomy. Five patients had unilateral frontotemporal hypometabolism (3 of 5 were seizure‐free), 1 had frontal hypometabolism, and 14 had no lateralized PET abnormality (4 of 7 were seizure‐free). Patients who became seizure‐free had significantly higher lateral temporal asymmetry index (AI). PET showed 315% relative temporal hypometabolism (AI) in 12 of 22 patients with non‐lateralized surface ictal VEEG and was capable of distinguishing between frontal and temporal foci in 16 of 24 patients with lateralized, but not localized, surface ictal video‐EEG. Conclusions: FDG‐PET provides valuable data in patients with unlocalized surface ictal EEG and can reduce the number of patients who require IEEG studies. Quantitation is necessary for optimal PET interpretation.
Temporal Changes in Proton MRS Metabolites After Kainic Acid‐Induced Seizures in Rat Brain
Authors: Najm I. M. , Wang Y. , Hong S. C. , Luders H. O. , Ng T. C. , Comair Y. G. 
Published: August 2005

Summary: Purpose: In situ 1H‐magnetic resonance spectroscopy (MRS) was used to study temporal metabolic changes in a rat model of temporal lobe epilepsy (TLE) by using kainic acid (KA). Methods: Rat brains were scanned at the level of the hippocampal body for MRS measurements. Relative ratios of N‐ acetyl groups (NA: N‐acetylaspartate and N‐acetylaspartyl glutamate), choline, and lactate (Lac) over creatine (Cr) were calculated. Results: NA/Cr ratios increased significantly during the ictal phase. During the postictal and interictal phases, the NA/Cr ratio decreased. There was a significant and prolonged increase of the lactate/Cr ratio in the hippocampi of rats that started 1 h after the onset of KA‐induced seizure activity and persisted up to 24 h after the injection. The prolonged lactate/Cr increase in an area susceptible to neuronal damage (e.g., hippocampus) correlated with the onset of seizure activity but remained elevated thereafter. Conclusions: The ictal and early postictal increase in lactate ratios may reflect increased cellular activity and metabolism resulting from KA excitotoxicity. Assuming that the changes in NA/Cr ratios are due to NAA increase, we speculate that an activation of the N‐acetylaspartylglutamate (NAAG) dipeptidase pathway may explain the ictal increase in NA/Cr ratios. The late postictal decrease in NNCr ratios is a reflection of KA‐induced neuronal cell loss.
Carbamazepine‐Induced Release of Serotonin from Rat Hippocampus In Vitro
Authors: Dailey John W. , Reith Maarten E. A. , Steidley Kevin R. , Milbrandt Joseph C. , Jobe Phillip C. 
Published: August 2005

Summary: Purpose: Carbamazepine is one of several antiepileptic drugs (AEDs) that release the inhibitory neurotransmitter serotonin as part of their pharmacodynamic action on brain neurons. We undertook this study to investigate the cellular processes by which carbamazepine (CBZ) releases serotonin from brain tissue. Methods: Tissue slices were prepared from hippocampi of Sprague‐Dawley rats. These hippocampal slices were preincubated in vitro in a buffer so that neurons within the slice would take up tritium‐labeled serotonin. Subsequently the slices were superfused with buffer containing CBZ or other chemicals (or both) that increase the overflow of serotonin radioactivity. Results: Carbamazepine produced a concentration‐dependent (50, 125, 250, or 500 μM) increase in basal overflow of serotonin radioactivity from superfused rat hippocampal slices in vitro. In contrast, these concentrations did not alter potassium‐stimulated release, suggesting that the CBZ‐induced release does not depend on depolarization or exocytosis. Blockade of the neuronal membrane serotonin transporter by fluoxetine (1 μM) or citaloprarn (2 μM) did not alter overflow of serotonin radioactivity produced by 250 μM CBZ. p‐chloramphetamine (10 μM) produced a substantial increase in overflow of serotonin radioactivity, and this effect appears to be antagonized by 250 μM CBZ. Uptake of [3H]‐labeled serotonin into hippocampal synaptosomes was inhibited by CBZ with a median inhibitory concentration (IC50) of 511 ± 33 μM and a Hill coefficient of 0.87 ± 0.11, suggesting competitive inhibition of uptake by CBZ. Conclusions: We conclude that CBZ (a) releases serotonin from hippocampal slices independent of exocytosis and by a mechanism not involving the neuronal membrane serotonin transporter, and (b) at high enough concentration, blocks the neuronal serotonin transporter.
Typical Absence Status in Adults: Diagnostic and Syndromic Considerations
Authors: Agathonikou A. , Panayiotopoulos C. P. , Giannakodimos S. , Koutroumanidis M. 
Published: August 2005

Summary: Purpose: To study the electroclinical features of typical absence status (TAS) in adults with syndromes of idio‐pathic generalized epilepsies (IGEs). Methods: Twenty‐one patients with one or more spells of TAS were identified among 136 consecutive adult patients with IGEs. All patients with TAS had comprehensive electroclinical investigations and EEG or video‐EEG recorded absences. Results: TAS occurred in 24.4% of 86 patients who had IGEs with typical absences alone or in combination with other seizures presisting in adult life. The prevalence of TAS appeared to be syndrome related, ranging from as high as 57.1% in perioral myoclonia with absences and 46.2% in “phantom” absences with GTCS to as low as 6.7% in juvenile myoclonic epilepsy. A varying degree of impairment of cognition was the cardinal clinical symptom shared in all TAS, but corresponding syndromes of IGE were often betrayed by other symptoms such as eyelid or perioral myoclonia. In phantom absences with GTCS, TAS was more numerous (p S 0.05) and more frequently the first overt seizure type (p = 0.006) than in any other IGE. Only in the syndrome of eyelid myoclonia with absences, TAS was always situation related, mainly as a result of antiepileptic drug discontinuation. Conclusions: The clinical EEG semiology and prevalence of TAS appear to be syndrome related with the highest prevalence in the syndromes of perioral myoclonia with absences and phantom absences with GTCS (p = 0.0024).
Analysis of Ictal EEGs of Epilepsy Associated with Tuberous Sclerosis
Authors: Ohmori Iori , Ohtsuka Yoko , Ohno Shigeru , Oka Eiji 
Published: August 2005

Summary: Purpose: To investigate the significance of cortical pathology of tonic spasms in patients with tuberous sclerosis. Methods: The subjects were 38 patients with epilepsy associated with tuberous sclerosis. We analyzed ictal EEGs of tonic spasms and partial seizures by means of video‐EEG monitoring for a total of 763 tonic spasms in 20 patients and 107 partial seizures in 15 patients. We also investigated the relation between partial seizures and magnetic resonance imaging (MRI) findings of these patients. Results: Ictal EEG patterns of tonic spasms were divided into generalized and focal patterns. Thirteen patients had only generalized patterns, whereas seven had both patterns. In five patients who had focal ictal patterns of tonic spasms and partial seizures, the location of focal patterns corresponded with the location of onset of partial seizures. Focal discharges were seen immediately before, after, and in the middle of tonic spasms in series in 13 patients. The location of focal discharges also corresponded with the location of the onset of partial seizures in 10 of the 13 patients. Regarding partial seizures, four patients had multiple active epileptogenic foci during the same period, and two others had shifting epileptogenic foci with increasing age. Conclusions: These findings indicate that cortical pathology plays an important role in the occurrence not only of partial seizures but also of tonic spasms in patients with tuberous sclerosis.
Cerebral Hemodynamic Response to Generalized Spike‐Wave Discharges
Authors: Diehl B. , Knecht S. , Deppe M. , Young C. , Stodieck S. R. G. 
Published: August 2005

Summary: Purpose: Data in the literature concerning metabolic demand during generalized spike‐wave activity (gSW) are conflicting. We investigated instantaneous changes in cerebral blood flow velocities (CBFV) in both middle cerebral arteries (MCAs) by transcranial Doppler sonography (TCD) during gSW paroxysms recorded by scalp EEG. Methods: In 13 patients, CBFVs in both MCAs were averaged, time‐locked to the occurrence of the gSW; respiratory rate (RR) and end‐expiratory pco, were measured in one patient. Results: Nine patients showed significant changes in CBFV during gSW. Four had biphasic flow changes with an initial increase (p < 0.05) and a subsequent decrease (p < 0.01). This was partially paralleled by an increase in RR (p < 0.01) and a decrease in pco, (p < 0.01). In three patients, an increase in CBFV that preceded the onset of gSW by several seconds was observed, followed by a decrease in CBFV. Two patients showed a significant decrease only of CBFV. Only gSWs of a median duration of >0.8 s were associated with significant changes in CBFV. Conclusions: We were able to demonstrate that gSWs of several seconds duration lead to cortical perfusion changes. We suggest that the initial increase of CBFV demonstrated in some patients reflects neuronal activation, whereas the subsequent decrease might in part be due to hyperventilation‐induced hy‐pocapnia.
Interictal Spiking Increases with Sleep Depth in Temporal Lobe Epilepsy
Authors: Malow Beth A. , Lin Xihong , Kushwaha Ramesh , Aldrich Michael S. 
Published: August 2005

Summary: Purpose: To test the hypothesis that deepening sleep activates focal interictal epileptiform discharges (IEDs), we performed EEG‐polysomnography in 21 subjects with medically refractory temporal lobe epilepsy. Methods: At the time of study, subjects were seizure‐free for 224 h and were taking stable doses of antiepileptic medications (AEDs). Sleep depth was measured by log delta power (LDP). Visual sleep scoring and visual detection of IEDs also were performed. Logistic‐regression analyses of IED occurrence in relation to LDP were carried out for two groups of subjects, nine with frequent IEDs (group 1) and 12 with rare IEDs (group 2). Results: The LDP differentiated visually scored non‐rapid eye movement (NREM) sleep stages (p = 0.0001). The IEDs were most frequent in NREM stages 3/4 and least frequent in REM sleep. Within NREM sleep, in both groups, IEDs were more frequent at higher levels of LDP (p < 0.05). In group 1, after accounting for the level of LDP, IEDs were more frequent (a) on the ascending limb of LDP and with more rapid increases in LDP (p = 0.007), (b) in NREM than in REM sleep (p = 0.002), and (c) closer to sleep onset (p < 0.0001). Fewer than 1% of IEDs occurred within 10 s of an EEG arousal. Conclusions: Processes underlying the deepening of NREM sleep, including progressive hyperpolarization in thalamocortical projection neurons, may contribute to IED activation in partial epilepsy. Time from sleep onset and NREM versus REM sleep also influence IED occurrence.
An Automated Injection System (with Patient Selection) for SPECT Imaging in Seizure Localization
Authors: Sepkuty Jehuda P. , Lesser Ronald P. , Civelek Cahid A. , Cysyk Barbara , Webber Robert , Shipley Roy 
Published: August 2005

Summary: Purpose: Ictal single‐photon‐emission computed tomography (Spect) provides lateralization but has technical limitations: (a) a “truly ictal” injection must be shortly after seizure onset; (b) therefore, a seizure of brief duration may be missed; (c) more than one patient may need testing at any given time: (d) a trained health professional must stay next to each patient to inject; and (e) because the radionuclide is placed in the syringe in advance of the injection, decay of the radioactive element could result in less than optimal uptake, if the same volume of material were to be used regardless of the time after ligand preparation. Methods: We developed an automated method of ligand injection that shortens time and increases efficiency of ictal SPECT ligand injection. By using an experimental setup, we compared manual injection times with times using an automated injection system. We determined relative costs and efficiency in work hours for the manual and automated methods. Results: Injection times were 8–14 s with automated versus 19–26 s with manual injection. Readjusting volume for “ligand” decay was simple and accurate with the automated system. Injection times for clinical SPECT studies in three patients were 13, 13, and 12 s, respectively. The price of one pump equals 120 work hours of a nurse or 24 ictal injection attempts. Much of the nurse's time is “wasted” because no seizure occurs. Conclusions: The method can be more efficient of staff, shorten injection time, and facilitate obtaining “truly ictal” injections. It allows more cost‐effective use of personnel.
Abdominal Epilepsy in an Adolescent with Bilateral Perisylvian Polymicrogyria
Authors: García‐Herrero D. , Fernhndez‐Torre J. L. , Barrasa J. , Calleja J. , Pascual J. 
Published: August 2005

Summary: Purpose: We report a patient with recurrent episodes of severe periumbilical pain accompanied by headache, pallor, dizziness, and visual hallucinations who was subsequently diagnosed as having abdominal epilepsy and a bilateral sylvian cortical malformation. Methods and Results: During an EEG examination, the patient had a simple partial seizure, manifested as intense abdominal pain. The ictal EEG showed a focal electrographic seizure arising from the left frontotemporal region. Computed tomography scan was normal; however, magnetic resonance imaging (MRI) revealed asymmetric lesions involving both sylvian fissures compatible with polymicrogyria. Onset of treatment with sodium valproate was followed by a significant reduction of seizures. Conclusions: Abdominal epilepsy should be suspected in adolescents or adults with paroxysmal episodes of abdominal pain associated with migraine‐like symptoms. EEG and MRI investigations are indicated. A developmental brain disorder should be considered as a possible etiology.
Enhanced Coagulation Activation by In Vitro Lipopolysaccharide Challenge in Patients with Ventricular Fibrillation Complicating Acute Myocardial Infarction
Authors: KÄLSCH THORSTEN , ELMAS ELIF , NGUYEN XUAN DUC , GREBERT NADINE , WOLPERT CHRISTIAN , KLÜTER HARALD , BORGGREFE MARTIN , HAASE KARL KONSTANTIN , DEMPFLE CARL ERIK 
Published: August 2005

Background: Indicators of coagulation and inflammation are elevated in patients with coronary heart disease. A role of coagulation activation in ventricular fibrillation during acute myocardial infarction has not been described. Methods and Results: Whole blood samples of 21 patients with a history of acute myocardial infarction complicated by ventricular fibrillation and whole blood samples of 18 patients without ventricular fibrillation were incubated with lipopolysaccharide (LPS). In both groups, the in vitro blood coagulation time was measured with the ReoRox®, a viscometric whole blood coagulometer. CD62P expression on platelets, tissue‐factor binding on monocytes, and platelet‐monocyte aggregates were measured with flow cytometry. Without LPS, no difference in the coagulation times were observed in both patient groups. After incubation with LPS, patients with a history of ventricular fibrillation showed a significantly decreased coagulation time compared to patients without ventricular fibrillation. The decrease of coagulation time after incubation with LPS also differed significantly in both groups. Expression of CD62P on platelets was significantly higher in patients with a history of ventricular fibrillation after incubation with LPS. Although in each patient group incubation with LPS induced a significantly increased amount of tissue factor on monocytes and a significantly increased the number of platelet‐monocyte aggregates, the two groups did not differ significantly concerning tissue factor binding on monocytes and the amount of platelet‐monocyte aggregates. Conclusions: After in vitro LPS challenge, patients with a history of ventricular fibrillation during myocardial infarction show an enhanced coagulation activation, which may partly be due to an enhanced platelet activation.
Genetics of Right Ventricular Cardiomyopathy
Authors: SEN‐CHOWDHRY SRIJITA , SYRRIS PETROS , McKENNA WILLIAM J. 
Published: August 2005

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited heart muscle disease that may result in arrhythmia, heart failure, and sudden death. The hallmark pathological findings are progressive myocyte loss and fibrofatty replacement, with a predilection for the right ventricle. However, variants of ARVC that preferentially affect the left ventricle are increasingly recognized. ARVC is distinguished from dilated cardiomyopathy by a propensity toward ventricular arrhythmia and sudden death in the absence of significant ventricular dysfunction.In the majority of families, ARVC shows autosomal dominant inheritance with incomplete penetrance. Recessive forms are also described, often in association with cutaneous disorders. Causative mutations have so far been identified in plakoglobin, desmoplakin, and plakophilin, all of which encode key components of the desmosome. Desmosomes are protein complexes that anchor intermediate filaments to the cytoplasmic membrane in adjoining cells, thereby forming a three‐dimensional scaffolding that provides tissues with mechanical strength. Unraveling of the genetic etiology of ARVC has elicited a new model for pathogenesis. Impaired functioning of cell adhesion junctions during exposure to shear stress may lead to myocyte detachment and death, accompanied by inflammation and fibrofatty repair. At least three mechanisms contribute to the arrhythmic substrate: bouts of myocarditis, fibrous and adipose infiltrates that facilitate macroreentry, and gap junction remodeling secondary to altered mechanical coupling. The latter may underlie arrhythmogenicity in early disease.Although ARVC can be considered a disease of the desmosome, a variety of other genetic defects give rise to phenocopies, which may ultimately enhance our understanding of the broad phenotypic spectrum.
DETECTION OF A PUTATIVE VIRULENCE cadF GENE OF CAMPYLOBACTER JEJUNI OBTAINED FROM DIFFERENT SOURCES USING A MICROFABRICATED PCR CHIP
Authors: POULSEN CLAUS R. , EL‐ALI JAMIL , PERCH‐NIELSEN IVAN R. , BANG DANG DUONG , TELLEMAN PIETER , WOLFF ANDERS 
Published: August 2005

ABSTRACT A microfabricated polymerase chain reaction (PCR) chip made of epoxy‐based photoresist (SU‐8) was recently designed and developed. In this study, we tested whether the PCR chip could be used for rapid detection of a potential virulence determinant, the cadF gene of Campylobacter jejuni. PCR was performed using published PCR conditions and primers for the C. jejuni cadF gene. DNA isolated from a C. jejuni reference strain CCUG 11284, C. jejuni isolates obtained from different sources (chicken and human), and Campylobacter whole cells were used as templates in the PCR tests. Conventional PCR in tube was used as the control. After optimization of the PCR chip, PCR positives on the chip were obtained from 91.0% (10/11) of the tested chips. A fast transition time was achieved with the PCR chip, and therefore a faster cycling time and a shorter PCR program were obtained. Using the PCR chip, the cadF gene could be detected in 1.5 h in comparison to 3.4 h in the published methods. The PCR chip can be applied for rapid detection of  the virulence cadF gene of C. jejuni obtained from different sources. This is the first PCR chip that has been used to detect Campylobacter virulence genes. Using the chip, the cadF gene of C. jejuni can be detected directly from bacterial whole cells without DNA isolation and purification steps.
Artificial Recharge in Las Vegas Valley, Clark County, Nevada
Authors: Katzer Terry , Brothers Kay 
Published: August 2005

ABSTRACTArtificially recharging the ground‐water system is one water resource option available to the Las Vegas Valley Water District in response to increasing water demand during summer peak periods. The existing water‐supply system for Las Vegas Valley is limited since peak water‐use demand periods in 10 to 20 years or less will require the construction of additional facilities. To prepare for these short‐term (and longer) demands, the Las Vegas Valley Water District, in cooperation with the U.S. Bureau of Reclamation, conducted a limited ground‐water recharge demonstration project using treated Colorado River water.A major concern of water managers regarding artificial recharge is the resulting water chemistry when treated (potable) Colorado River water is injected into the ground‐ water system. Both waters are high in calcium creating a potential for calcite precipitation which, in addition to clogging the perforations in the water well casing, could potentially reduce aquifer permeabilities by clogging the pore space of the flow media.Approximately 525,000 gallons of potable water were injected into a semiconfined ground‐water aquifer over a three‐day period interspersed with two pumping periods. Water chemistry samples taken throughout the injection project showed no imbalance with regard to calcium or any other chemical constituent. Therefore, artificial recharge is feasible and is one water resource technique available to meet an increasing water demand based on the existing water quality of the Colorado River and the quality of the ground water in the area of injection.