bluuebunny/crossref_metadata_2025 huggingface dataset:
Family Studies and Human Leukocyte Antigen Class II Typing in Indian Probands with Seizures in Association with Single Small Enhancing Computed Tomography Lesions
Authors: Jain S. , Padma M. V. , Kanga U. , Mehra N. K. , Puri A. , Maheshwari M. C.
Published: August 2005

Summary: Purpose: To define the clinical features of the syndrome of seizures associated with single, small, enhancing computed tomography (CT) lesions (SSELs) in 235 Indian probands and seizure types among their family members. Human leukocyte antigen (HLA) class II genomic typing in randomly selected 41 probands was done to identify the role of hereditary factors in this syndrome.

Methods: The seizure types among 235 probands, their clinical outcome, and seizures in their family members were studied. Family data were collected on relatives of 212 additional probands with neurologic diseases other than epilepsy. HLA class II antigens were studied by using polymerase chain reaction (PCR) amplified DNA and sequence‐specific oligonucleotide probe (PCR‐SSOP) hybridization.

Results: The seizures in 86% were partial with or without generalization; 77% had fewer than five seizures before the first CT scan. Evanescent focal neurologic deficits after seizures were noted in 40%. Most patients (97%) were treated with a single antiepileptic drug (AED). Significant resolution of the CT scan lesion was noted within 6 months in 125 (53%) of 235 cases. Two thirds of patients had no seizures while taking a single AED, and an additional 18% had no seizures even after their AEDs were discontinued. Epilepsy among relatives of Indian probands having seizures in association with SSELs was more common as compared with relatives of probands with other neurologic diseases. A family history of seizures was noted in 21% probands, the ratio of affected first‐ to second‐ degree relatives was 4.3:1, and 60% of affected sibs had syndromic concordance with probands. There was a positive association of HLA‐DRB1*13 (Pc= 0.036) with this syndrome.

Conclusions: The syndrome of seizures in association with SSELs seems to be a benign localization‐related epileptic syndrome. Our results of HLA studies point to an inherited susceptibility to an infective agent, which in most cases is of cysticercal etiology.
Prognostic Implication of Contralateral Secondary Electrographic Seizures in Temporal Lobe Epilepsy
Authors: Lee Ki Hyeong , Park Yong D. , King Don W. , Meador Kimford J. , Loring David W. , Murro Anthony M. , Smith Joseph W.
Published: August 2005

Summary: Purpose: Interhemispheric propagation of seizures in temporal lobe epilepsy is frequently noted during intracranial EEG monitoring. We hypothesized that a distinct secondary electrographic seizure (DSES) in the temporal lobe contralateral to primary seizure onset may be an unfavorable prognostic indicator.

Methods: We reviewed intracranial depth electrode EEG recordings, 1‐year outcome, and medical records of 51 patients (M 29, F 22: age 15–64 years) who underwent anterior temporal lobectomy during 1988–96. We defined DSES as a seizure that spread to the contralateral temporal lobe and produced distinct contralateral EEG features. The distinct feature was focal involvement of one or two electrode contacts at onset, which starts and evolves independently from the ipsilateral temporal lobe. We considered DSES as the predominant seizure pattern when it occurred in more than one half of the patients' recorded seizures.

Results: Only nine of 19 (47%) patients with predominant DSES had a 1‐year seizure‐free outcome, whereas 27 of 32 (84%) patients without predominant DSES had a 1‐year seizure‐free outcome (p <0.01). Bitemporal independent seizures were more common in patients with predominant DSES (9/19 versus 0/32; p <0.001).

Conclusion: Our results suggest that distinct contralateral secondary electrographic seizure is a predictor of unfavorable outcome and is also more likely to be associated with bitemporal seizures.
The Clinical Usefulness of Ictal Surface EEG in Neocortical Epilepsy
Authors: Lee Sang Kun , Kim Joo‐Yong , Hong Keun‐Sik , Nam Hyun‐Woo , Park Sung‐Ho , Chung Chun‐Ki
Published: August 2005

Summary: Purpose: Localizable scalp EEGs, during ictal episodes, appear to be rare in neocortical epileptic syndromes. However, studies based on large numbers of patients are also rare. This study aims to identify the characteristic patterns of variable neocortical epilepsies and to evaluate their clinical usefulness in the localization of epileptogenic focuses.

Methods: We retrospectively assessed 394 noninvasive ictal recordings from 86 patients who subsequently underwent invasive study and resective surgery. Ictal EEGs were recorded using a video‐EEG monitoring system with electrodes placed according to the International 10–20 system, with additional anterior temporal electrodes. The ictal recordings were analyzed according to localizing accuracy and frequency characteristics. The durations of discrete or regional ictal rhythms were also measured.

Results: The percentage of discrete or regional EEGs was 23% in frontal lobe epilepsy, 52% in lateral temporal lobe epilepsy, 70% in occipital lobe epilepsy, and 10% in parietal lobe epilepsy. In order of frequency, the localizable ictal rhythms were theta, beta, alpha, delta, and rhythmic spike‐and‐wave. The duration of discrete or regional ictal rhythms was significantly shorter in frontal lobe epilepsy and parietal lobe epilepsy than in other epilepsies. Ictal beta activity was the most common rhythm in discrete‐patterned EEGs. Structural lesions found on MRI did not significantly affect the localization of epileptogenic focuses in the patients. The type of seizure was not related to the degree of localization, with the exception of simple partial seizure.

Conclusions: Ictal surface EEG was clinically helpful in the localization of epileptogenic focuses in at least some neocortical epileptic syndromes.
Neurocognitive Attention and Behavior Outcome of School‐Age Children with a History of Febrile Convulsions: A Population Study
Authors: Chang Ying‐Chao , Guo Nai‐Wen , Huang Chao‐Ching , Wang Shan‐Tair , Tsai Jing‐Jane
Published: August 2005

Summary: Purpose: A prospective population‐based case‐control study was performed to ascertain whether febrile convulsion (FC) in early childhood is associated with neurocognitive attention deficits in school age.

Methods: A total of 103 children, confirmed to have FC by age 3 years from a population survey of 4,340 live‐birth new‐borns in Tainan City, Taiwan, was followed up until at least age 6 years. An achievement test, behavioral ratings, and computerized neurocognitive battery assessing various subcomponents of attention were given to 87 FC children (FC group) and 87 randomly selected population‐matched control (CC group).

Results: Compared with the CC group, the FC group did not have scholastic performance or behavioral outcome disadvantage. Overall FC group performance was distinguished by significantly higher scores in the achievement test and fewer missing errors (p <0.005) and commission errors (p <0.05), less variability in reaction time (p <0.005), and a nonsignificant trend of impulsivity. Attention performance of the FC and CC groups were comparable. Within the FC group, age at onset, complex FC, recurrence of FC, development of unprovoked seizures, or prior use of phenobarbital had no adverse effects on neurocognitive attention outcome.

Conclusions: This population study suggests that FC in early childhood does not have adverse effects on behavior, scholastic performance, and neurocognitive attention. On the contrary, the FC group demonstrated significantly better control of distractibility and attention at school age.
Functional Mapping of the Insular Cortex: Clinical Implication in Temporal Lobe Epilepsy
Authors: Ostrowsky Karine , Isnard Jean , Ryvlin Philippe , Guénot Marc , Fischer Catherine , Mauguière Francois
Published: August 2005

Summary: Purpose: We report the results of 75 intracortical electrical stimulations of the insular cortex performed in 14 patients during stereo‐electroencephalography (SEEG) investigation of drug‐resistant partial epilepsy. The insular cortex was investigated on electroclinical arguments suggesting the possibility of a perisylvian spread or a rapid multilobar diffusion of the discharges during video EEG.

Methods: In these 14 patients, 27 stereotactically implanted transopercular electrodes reached the insular cortex (11 the right insula, 16 the left insula). Square pulses of current were applied between the two deepest adjacent contacts of each transopercular electrode using low (1 Hz) or high‐frequency (50 Hz) stimulation. Only symptoms evoked in the absence of afterdischarges were analyzed.

Results: Clinical responses were evoked in 10 of the 14 patients (in 20 of the 27 insular sites) and showed a clear topographic specificity inside the insular cortex. Viscerosensitive and visceromotor responses, similar to those evoked by temporomesial stimulation, were evoked by anterior insular stimulation and somesthetic sensation, similar to those evoked by opercular cortex stimulation, by posterior insular stimulation.

Conclusions: The topographic organization of the induced responses within the insular cortex suggest that two different cortical networks, a visceral network extending to the temporomesial structures and a somesthetic network reaching the opercular cortex, are disturbed with stimulation of the anterior or the posterior insula, respectively. Thus ictal symptoms associated with the spread of the epileptic discharges to the insular cortex might be difficult to distinguish from those usually reported during temporomesial or opercular discharges.
Relationships Between Seizure Severity and Health‐Related Quality of Life in Refractory Localization‐Related Epilepsy
Authors: Vickrey Barbara G. , Berg Anne T. , Sperling Michael R. , Shinnar Shlomo , Langfitt John T. , Bazil Carl W. , Walczak Thaddeus S. , Pacia Steven , Kim Sehyun , Spencer Susan S. ,   for the Multicenter Epilepsy Surgery Study
Published: August 2005

Summary: Purpose: To evaluate relationships between self‐report measures of seizure severity and health‐related quality of life (HRQOL) in people with refractory localization‐related epilepsy.

Methods: A sample of 340 adults enrolled in a seven‐center, prospective study of resective epilepsy surgery completed baseline questionnaires that included the Quality of Life in Epilepsy (QOLIE)‐89 and a seven‐item adaptation of the National Hospital Seizure Severity Scale. Associations between QOLIE‐89 summary measures and both the total seizure severity scale score and individual seizure severity items were assessed, after adjustment for seizure frequency.

Results: The seizure severity measure had adequate scale score variability and reliability in this sample. Correlations between individual items in the scale did not exceed 0.43. Product‐moment partial correlations between the seizure severity scale and QOLIE‐89 summary measures ranged from −0.17 to −0.29 (all p values <0.01). Of the seven seizure severity items, the average time before individuals perceived they were “really back to normal” after their seizures was broadly related to all domains of HRQOL (r values ranged from −0.16 to −0.30; p values <0.01). Severity of injury during seizures was the only other item having more than minimal associations with HRQOL, and it was selectively related to the physical health measure. Higher frequency of falls during seizures was modestly related to less employment.

Conclusions: This seizure severity measure assesses constructs that are generally distinct from HRQOL, except for moderate and broad associations between HRQOL and patient's perceptions of the average duration of recovery time after seizures. Recovery time may potentially be a useful clinical indicator of seizure severity that reflects meaningful impairment of HRQOL in adults with frequent seizures.
Effect of Ganaxolone on Flurothyl Seizures in Developing Rats
Authors: Liptáková Soňa , Velíšek Libor , Velíšková Jana , Moshé Solomon L.
Published: August 2005

Summary: Purpose: To determine the effects of a newly synthesized epalon, ganaxolone (GNX), on primarily generalized seizures in rats of various ages during development. Epalons are classified as neuroactive steroids that interact at unique site of the GABAA receptor‐Cl− channel complex in the central nervous system.

Methods: Sprague‐Dawley male rats were used at 9, 15, 30, and 60 postnatal days (PN). GNX dissolved in 2‐hydroxypropyl‐β‐cyclodextrine was administered intraperitoneally in different doses at various time points before flurothyl testing. The incidence and threshold of clonic and tonic‐clonic flurothyl seizures were evaluated. Behavioral changes were also assessed.

Results: In all age groups, the effects of GNX were dose dependent and more prominent 10 min after its administration. In PN 60 and PN 30 rats, GNX had dose‐dependent anticon‐vulsant effects; tonic‐clonic seizures were more sensitive to GNX treatment than clonic seizures. In PN 15 and PN 9 rats, GNX demonstrated dose‐ and time‐dependent anticonvulsant effects against both types of flurothyl‐induced seizures. GNX was more effective in PN 15 rats than in other age groups, but at doses that altered motor behavior.

Conclusions: GNX has anticonvulsant effects against flurothyl‐induced seizures in all age groups tested. Its effects are more prominent in the two younger age groups, especially in PN 15 rats, but are associated with motor side effects.
Factors Predictive of the Outcome of Frontal Lobe Epilepsy Surgery
Authors: Mosewich R. K. , So E. L. , O'Brien T. J. , Cascino G. D. , Sharbrough F. W. , Mars W. R. , Meyer F. B. , Jack C. R. , O'Brien P. C.
Published: August 2005

Summary: Purpose: To identify factors that predict the outcome in seizure control after frontal lobe epilepsy surgery (FLES). FLES is the second most frequent type of epilepsy surgery, but the results are generally not as good as those after anterior temporal lobectomy.

Methods: Our cohort consisted of 68 consecutive patients whose first epilepsy surgery involving the frontal lobe occurred between 1987 and 1994. Clinical history and results of imaging and electroencephalographic studies were reviewed in detail. Excellent outcome was defined as being seizure free or having only nondisabling seizures at last follow up.

Results: Forty of the 68 patients (58.8%) had an excellent outcome; none of the patients with a history of childhood febrile seizures had an excellent outcome, whereas outcome was excellent in 63% of those without that history (p 0.01). The other significant presurgical factor was the presence of a potentially epileptogenic lesion in the frontal lobe on neuroimaging (excellent outcome in 72% when present versus 41% when absent, p 0.001). The only significant postsurgical factor was early postoperative seizure control in the first year (excellent outcome in 96% with early control versus 25% without, p 0.01).

Conclusions: History of childhood febrile seizures is a poor prognostic factor in FLES patients. It may suggest that the structural basis of all or some of the patients' intractable seizures is mesial temporal sclerosis. On the other hand, neuro‐imaging detection of a potentially epileptogenic frontal lobe lesion and early postoperative seizure control are associated with subsequent excellent outcome.
Refractory Idiopathic Absence Status Epilepticus: A Probable Paradoxical Effect of Phenytoin and Carbamazepine
Authors: Osorio Ivan , Reed R. C. , Peltzer Jill N.
Published: August 2005

Summary: Purpose: To compare the frequency of seizures and status epilepticus and their response to first‐line drugs in patients with idiopathic generalized epilepsies receiving carba‐mazepine or phenytoin to those receiving other drugs or no treatment.

Methods: We performed a retrospective chart review of all cases of idiopathic generalized epilepsies treated by the authors between 1985 and 1994. We compared seizure frequency and mean intravenous benzodiazepine dose required to control absence status epilepticus, intraindividually in subjects on carba‐mazepine or phenytoin before and after discontinuation of these compounds, and interindividually to subjects without treatment or receiving other drugs.

Results: Bouts of absence or tonic‐clonic status epilepticus and seizures in subjects treated with phenytoin or carbamaze‐pine at therapeutic concentrations were considerably more frequent and proved intractable to treatment with valproic acid or benzodiazepines, compared with a cohort of subjects also with idiopathic generalized epilepsies, but naive to, or receiving sub‐therapeutic or therapeutic doses of other agents.

Conclusions: Our observations strongly suggest that therapeutic concentrations of phenytoin and carbamazepine exacerbate idiopathic generalized epilepsies. Subjects in whom absence is one of the seizure types seem at a particularly high risk for responding paradoxically. These findings underscore the value of accurate classification of seizures and particularly the syndromic approach to diagnosis and point to the potential for iatrogenic complications with indiscriminate use of antiseizure drugs.
Fenfluramine Blocks Low‐Mg2+‐Induced Epileptiform Activity in Rat Entorhinal Cortex
Authors: Gentsch K. , Heinemann U. , Schmitz B. , Behr J.
Published: August 2005

Summary: Purpose: The entorhinal cortex (EC) represents the main input structure to the hippocampus and seems to be critically involved in temporal lobe epilepsy. Considering that the EC receives a strong serotonergic projection from the raphe nuclei and expresses a high density of serotonin (5‐HT) receptors, the effect of the 5‐HT–releasing drug fenfluramine (FFA) on epileptiform activity generated in the EC was investigated in an in vitro model of epilepsy.

Methods: The experiments were performed on 43 horizontal slices containing the EC, the subiculum, and the hippocampal formation obtained from 230–250 g adult Wistar rats. Using extracellular recording techniques, we investigated the effect of bath‐applied FFA (200 μmol/L to 1 mmol/L) on epileptiform activity induced by omitting MgSO4 from the artificial cerebrospinal fluid.

Results: We demonstrate that FFA reversibly blocks epileptiform activity in the EC. Surprisingly, in the presence of the 5‐HT uptake blocker paroxetine, the FFA‐induced effect was diminished. Coapplication of the 5‐HTIA receptor antagonist WAY 100635 prevented the FFA‐induced anticonvulsive effect, suggesting that (a) the FFA‐induced suppression of epileptiform activity is mediated by the release of 5‐HT from synaptic terminals within the EC rather than by an unspecific effect of FFA and (b) released 5‐HT most likely blocks the activity by activation of 5‐HTIA receptors.

Conclusion: FFA, which is primarily used because of its anorectic activity, might get an additional therapeutic value in the treatment of temporal lobe epilepsy with parahippocampal involvement.
Tonic Seizures: Their Significance for Lateralization and Frequency in Different Focal Epileptic Syndromes
Authors: Werhahn Konrad J. , Noachtar Soheyl , Arnold Stephan , Pfänder Mona , Henkel Anja , Winkler Peter A. , Lüders Hans O.
Published: August 2005

Summary: Purpose: To determine whether the clinical features of tonic seizures (TSZ) are useful for lateralization of epileptic syndromes and the differential diagnosis of focal epileptic syndromes.

Methods: From a group of 481 patients, 123 patients with TSZ (44 females; mean age, 22.9 years; mean age at onset, 7 years; mean duration of epilepsy, 16 years) were selected. A total of 1595 epileptic seizures, documented during video‐electroencephalographic monitoring, were analyzed. Patients who had had surgery for epilepsy previously were excluded. Seizures were classified using a semiological seizure classification. Epilepsy syndromes were classified using all test data (electroencephalography, magnetic resonance imaging, computed tomography, positron emission tomography, and single‐photon emission tomography). Data were compared using χ2 analysis or the Fisher exact test.

Results: More patients with TSZ had extratemporal than temporal lobe epilepsies (79% vs. 1.7%; p < 0.0001) among those with an epilepsy localized to one lobe (n = 306). In the 123 patients, TSZ were part of 170 different seizure evolutions. Seizure evolutions began with TSZ as the first seizure type more often in patients with frontal lobe epilepsy (FLE) compared with patients with parieto‐occipital lobe epilepsy (POLE) (40% in POLE vs. 67% in FLE; p < 0.05). In contrast, TSZ in POLE were more likely to be preceded by auras (50% in POLE vs. 26% in FLE; p < 0.05). TSZ were bilateral in 129 (76%) and unilateral in 41 (24%) seizure evolutions. Unilateral TSZ correctly lateralized the epilepsy syndrome to the contra‐lateral hemisphere.

Conclusion: Analysis of seizure semiology and evolution in patients with TSZ is helpful for differentiating between focal epilepsies of temporal, frontal, and parieto‐occipital origin. Unilateral TSZ provide useful information for the lateralization of the epileptic syndrome.
Multicenter Double‐Blind, Randomized, Placebo‐Controlled Trial of Levetiracetam as Add‐On Therapy in Patients with Refractory Partial Seizures
Authors: Shorvon Simon D. , Löwenthal Armand , Janz Dieter , Bielen Edith , Loiseau Pierre ,   for the European Levetiracetam Study Group
Published: August 2005

Summary: Purpose: To evaluate the efficacy and tolerability of levetiracetam (LEV, Keppra) as add‐on therapy in patients with refractory partial seizures.

Methods: In this European multicenter, double‐blind, randomized, placebo‐controlled trial, LEV (500 or 1,000 mg twice daily) was compared with placebo as add‐on therapy in 324 patients with uncontrolled simple or complex partial seizures, or both, with or without secondary generalization. After enrollment, three parallel groups were assessed during a baseline period of 8 or 12 weeks, followed by a 4‐week titration interval and a 12‐week evaluation period.

Results: LEV significantly decreased partial seizure frequency compared with placebo. A reduction in seizure frequency of 50% occurred in 22.8% of patients in the 1,000‐mg group and 31.6% of patients in the 2,000‐mg group, compared with 10.4% of patients in the placebo group. Administration of LEV did not affect plasma concentrations of concomitant an‐tiepileptic drugs or alter vital signs or laboratory parameters. No significant difference in the incidence of adverse events was observed between treatment groups (70.8% for the 1,000‐mg group and 75.5% for the 2,000‐mg group), or between the LEV and placebo groups (73.2% for placebo group). The most commonly reported adverse effects in the LEV group were asthenia, headache, and somnolence.

Conclusions: The antiepileptic efficacy and tolerability of LEV (1,000 mg/d and 2,000 mg/d, administered in two divided doses) as add‐on therapy was established in patients with refractory partial seizures in this clinical study.
Relationship of Seizure Frequency to Hippocampus Volume and Metabolism in Temporal Lobe Epilepsy
Authors: Spanaki M. V. , Kopylev L. , Liow K. , DeCarli C. , Fazilat S. , Gaillard W. D. , Theodore W. H.
Published: August 2005

Summary: Purpose: To examine the relationship between frequency of complex partial (CPS) and secondarily generalized tonic‐clonic seizures (sGTCS) on hippocampal volume (HV) and temporal lobe metabolism.

Methods: We performed volumetric magnetic resonance imaging (MRI) and positron emission tomography with 18fluorodeoxyglucose (18FDG‐PET) in 32 patients with epilepsy. Temporal lobe foci were localized by ictal video‐EEG.

Results: We did not find any association between CPS frequency or lifetime number of sGTCS and HV or metabolism ipsilateral to electroencephalographic focus.

Conclusion: The progress of metabolic or pathologic abnormalities of temporal lobe epilepsy may not be altered by adequate seizure control. The presence of an epileptic focus might be associated with progressive neuronal injury even in clinically well‐controlled patients.
Epilepsy Can Be Diagnosed When the First Two Seizures Occur on the Same Day
Authors: Camfield Peter , Camfield Carol
Published: August 2005

Summary: Purpose: Experts have suggested that when the first two (or more) unprovoked seizures occur on the same day, they should be considered as a single event and the diagnosis of epilepsy await a further seizure. We have studied the subsequent clinical course of children with their first two seizures on the same day (“same day” group) compared with children with their first two seizures separated by more than one day (“different day” group).

Method: The Nova Scotia childhood epilepsy database documented all newly diagnosed children with epilepsy from 1977 to 1985 with follow‐up in 1990 and 1991. Epilepsy was defined as two or more unprovoked seizures regardless of the interval between seizures provided that consciousness fully returned between seizures. All patients had their first seizure between the ages of 1 month and 16 years. Seizure types were restricted to partial, generalized tonic‐clonic, and partial with secondary generalization.

Results: Of the 490 children with partial or generalized tonic‐clonic seizures and follow‐up of more than 2 years, 70 had their first two or more seizures on the same day and 420 had their first two seizures on different days. Eighty percent (56 of 70) of the “same day” group subsequently had one or more further seizures with (n = 14) or without (n = 42) medication; 80.9% (340 of 420) of the “different day” group had one or more further seizures with (n = 115) or without (n = 225) medication. Seizure types were nearly identical. Cause was the same (except for fewer idiopathic “genetic” cases in the “same day” group: 1 of 70 vs. 42 of 420; p = 0.02). Rates of mental handicap and previous febrile seizures were the same. Children in the “same day” group were younger on average (60 vs. 84 months; p = 0.001) and were somewhat more likely to have neurological impairment. Outcome after 7 years average follow‐up was the same: 58% of the “same day” group and 56% of the “different day” group were in remission.

Conclusion: If two or more unprovoked seizures (with normal consciousness between) occur on the same day, the child appears to have epilepsy and will have a clinical course identical to that of the child with a longer time interval between the first two seizures.
Photogenic Partial Seizures
Authors: Hennessy Michael J. , Binnie Colin D.
Published: August 2005

Summary: Purpose: To establish the incidence and symptoms of partial seizures in a cohort of patients investigated on account of known sensitivity to intermittent photic stimulation and/or precipitation of seizures by environmental visual stimuli such as television (TV) screens or computer monitors.

Methods: We report 43 consecutive patients with epilepsy, who had exhibited a significant EEG photoparoxysmal response or who had seizures precipitated by environmental visual stimuli and underwent detailed assessment of their photosensitivity in the EEG laboratory, during which all were questioned concerning their ictal symptoms.

Results: All patients were considered on clinical grounds to have an idiopathic epilepsy syndrome. Twenty‐eight (65%) patients reported visually precipitated attacks occurring initially with maintained consciousness, in some instances evolving to a period of confusion or to a secondarily generalized seizure. Visual symptoms were most commonly reported and included positive symptoms such as coloured circles or spots, but also blindness and subjective symptoms such as “eyes going funny”Other symptoms described included nonspecific cephalic sensations, deja‐vu, auditory hallucinations, nausea, and vomiting. No patient reported any clear spontaneous partial seizures, and there were no grounds for supposing that any had partial epilepsy excepting the ictal phenomenology of some or all of the visually induced attacks.

Conclusions: These findings provide clinical support for the physiological studies that indicate that the trigger mechanism for human photosensitivity involves binocularly innervated cells located in the visual cortex. Thus the visual cortex is the seat of the primary epileptogenic process, and the photically triggered discharges and seizures may be regarded as partial with secondary generalization.
Twenty Years of Ictal EEG–EMG
Authors: Mothersill I. W. , Hilfiker P. , Krämer G.
Published: August 2005

Summary: This study aimed to evaluate the use of ictal EEG recordings combined with simultaneous surface EMG in the diagnosis and analysis of motor events, both epileptic and non‐epileptic. All ictal registrations were performed utilizing radio/cable telemetry. Routine recordings consisted of 18‐channel EEG plus 8‐channels bipolar surface EMG in freely moving patients. Combined ictal EEG—EMG recordings in freely moving patients enabled us to identify and define the following pathomechanisms of epileptic drop seizures, epileptic axial spasms, atonic, myoclonic‐atonic, and akinetic seizures. Precise differentiation could be made between tonic and nontonic postural seizures and between startle‐induced reflex seizures and hyperekplexia. The findings from telemetered ictal recordings in freely moving patients with combined EEG and surface EMG offer the only means of identifying, defining, and differentiating motor events, both epileptic and nonepileptic, of a short duration that cannot be properly differentiated by clinical examination alone.
Integration of EEG, MRI, and SPECT in Localizing the Seizure Focus for Epilepsy Surgery
Authors: So Elson L.
Published: August 2005

Summary: Several modalities are now available for detecting the structural and the functional abnormalities of a seizure focus. This article discusses the principles and techniques that can be used to integrate the data derived from different test modalities in delineating the seizure focus in epilepsy surgery candidates. An approach in integrating EEG, MRI, and SPECT abnormalities is described to demonstrate how the spatial relationships among them can be precisely determined by co‐registering images of the abnormalities on the MRI. The recently developed technique of subtraction ictal SPECT co‐registered to MRI (SISCOM) can reveal a discrete hyperperfusion focus with its relationship to the cerebral anatomy. The SISCOM focus can also serve as a target for intracranial electrode implantation and for subsequent surgical resection. This can be achieved by using a computer‐based system of relating the image space to the surgical field. The limitations of each test in localizing the surgical seizure focus must be recognized when the value of each test is interpreted relative to those of other tests. In many patients, not all tests will show localizing abnormalities, and the foci determined by different tests may be incongruent. When the location of the focus is not compatible with the possible origin of the patient's habitual seizures, further evaluation with other tests, including intracranial EEG recordings, is necessary. The decision in determining which tests and how many to employ for localizing the surgical focus must be individualized for each patient.
What is GABAergic Inhibition? How Is it Modified in Epilepsy?
Authors: Bernard C. , Cossart R. , Hirsch J. C. , Esclapez M. , Ben‐Ari Y.
Published: August 2005

Summary: A deficit of γ‐aminobutyric acid‐ergic (GABAergic) inhibition is hypothesized to underlie most forms of epilepsy. Although apparently a straightforward and logical hypothesis to test, the search for a deficit of GABAergic inhibition in epileptic tissue has revealed itself to be as difficult as the quest for the Holy Grail. The investigator faces many obstacles, including the multiplicity of GABAergic inhibitory pathways and the multiplicity of variables that characterize the potency of inhibition within each inhibitory pathway. Perhaps more importantly, there seems to be no consensual definition of GABAergic inhibition. The first goal of this review is to try to clarify the notion of GABAergic inhibition. The second goal is to summarize our current knowledge of the various alterations that occur in the GABAergic pathways in temporal lobe epilepsy. Two important features will emerge: (a) according to the variable used to measure GABAergic inhibition, it may appear increased, decreased, or unchanged; and (b) these modifications are brain area‐ and inhibitory pathway‐specific. The possible functional consequences of these alterations are discussed.
Synaptic Properties of Neocortical Neurons in Epileptic Mice Lacking the Otx1 Gene
Authors: Avanzini G. , Spreafico R. , Cipelletti B. , Sancini G. , Frassoni C. , Franceschetti S. , Lavazza T. , Panzica F. , Acampora D. , Simeone A.
Published: August 2005

Summary: Purpose: The murine homeobox‐containing Otx gene is required for correct nervous system and sense organ development. Otx1−/− mice obtained by replacing Otx with the lac Z gene show developmental abnormalities of the cerebellum, mesencephalon, and cerebral cortex associated with spontaneous epileptic seizures (1). The epileptogenic mechanisms accounting for these seizures were investigated by means of electrophysiological recordings made from neocortical slices.

Methods: The 400‐μm slices were prepared from the somato‐sensory cortex of Otx1−/− and Otx1+/+ mice, and the current clamp intracellular recordings were obtained from layer V pyramidal neurons by means of pipettes containing K+ acetate 1·5 mol/L and biocytin 2% (pH 7·3).

Results: Synaptic responses could be evoked in the neocortical pyramidal neurons by electrically stimulating the underlying white matter. μ‐Aminobutyric acid A/B—mediated inhibitory postsynaptic potentials were more pronounced in the Otx1−/− than in the control pyramidal neurons from the earliest postnatal period; multisynaptic excitatory postsynaptic potentials were significantly more expressed in the Otx1−/− mice also at the end of the first postnatal month, when they were only rarely encountered in controls.

Conclusion: Excessive excitatory amino acid—mediated synaptic driving may lead to a hyperexcitable condition that is responsible for the epileptic manifestations occurring in Otx1−/− mice. This excess of excitation is not counteracted by well‐developed γ‐aminobutyric acid activity, which seems to be involved in the synchronization of cell discharges. Our ongoing and more extensive comparative analysis of the mutants and controls should help to clarify the way in which the putative rearrangement taking place in Otx1−/− neocortex may lead to the excitatory hyperinnervation of layer V pyramidal neurons.
Concentration—Effect Studies with Topiramate on Selected Enzymes and Intermediates of the GABA Shunt
Authors: Sills Graeme J. , Leach John P. , Kilpatrick W. Stewart , Fraser Caroline M. , Thompson George G. , Brodie Martin J.
Published: August 2005

Purpose: Topiramate (TPM) is a new antiepileptic agent with a multifactorial mechanism of action. The drug potentiates responses to γ‐aminobutyric acid (GABA) at the GABAA receptor and has inhibitory effects on neuronal sodium channels, the AMPA/kainate subtype of glutamate receptor, and carbonic anhydrase. Recent evidence has, however, suggested that the drug also increases brain GABA concentrations in humans. These studies were designed to investigate the neurochemical basis of this observation.

Methods: Adult male mice were randomised into two groups and administered TPM (0–1,000 mg/kg) intraperitoneally either as a single dose or daily for 8 days. At 4 h after the final dose, brain tissues were analysed for concentrations of GABA, glutamate, and glutamine and for the activities of GABA‐transaminase and glutamic acid decarboxylase. TPM levels in brain also were determined.

Results: Single‐dose and repeated TPM treatments were without effect on all of the parameters investigated, although the drug was detectable in the brain at doses of 10 mg/kg.

Conclusions: These results contradict the reported increase in brain GABA concentrations with TPM. More detailed studies are required to determine the basis of this clinical observation and the extent to which it contributes to the antiepileptic activity of the drug.
Classification of Psychiatric Symptoms in Patients with Epilepsy
Authors: Onuma Teiichi
Published: August 2005

Summary: Epilepsy is a neurological disorder, but many patients with epilepsy also have psychiatric symptoms. These symptoms and the underlying psychopathology vary considerably among patients, and the classification of these symptoms is disputed. Some classifications are based on the psychiatric symptomatology, the presence or absence of disturbance of consciousness, the EEG abnormalities, or the temporal relation between the symptoms and the seizures. The International Classification of Mental and Behavioral Disorders: Clinical Description and Diagnostic Guidelines (ICD‐10) is accepted worldwide in psychiatry. The feasibility of classifying the psychiatric symptoms associated with the epilepsy according to the ICD‐10 classification was studied. It was concluded that only symptoms in cases of epilepsy where there is a clear sensorium might be appropriately classified by the ICD‐10. The classification of psychiatric symptoms in epilepsy needs further investigation.
Clifford Algebra Exponentials and Planar Linkage Synthesis Equations
Authors: Perez Alba , McCarthy J. Michael
Published: August 2005

This paper uses the exponential defined on a Clifford algebra of planar projective space to show that the “standard-form” design equations used for planar linkage synthesis are obtained directly from the relative kinematics equations of the chain. The relative kinematics equations of a serial chain appear in the matrix exponential formulation of the kinematics equations for a robot. We show that formulating these same equations using a Clifford algebra yields design equations that include the joint variables in a way that is convenient for algebraic manipulation. The result is a single formulation that yields the design equations for planar 2R dyads, 3R triads, and nR single degree-of-freedom coupled serial chains and facilitates the algebraic solution of these equations including the inverse kinematics of the chain. These results link the basic equations of planar linkage design to standard techniques in robotics.
On Predicting Softening Effects in Hard Turned Surfaces—Part I: Construction of Material Softening Model
Authors: Shi Jing , Liu C. Richard
Published: August 2005

The need for predicting material microstructure and hardness in hard turned surfaces becomes very urgent in that hard turning is adopted by industries as a finishing process, and the produced surface integrity, including microstructure and hardness, is well known to be a determining factor for part service performance. This study focuses on the prediction of material softening and is composed of two parts, namely, the construction of material softening model based on thermal history and the prediction of thermal history by finite element modeling of hard turning. In this part of the research, three material softening models based on thermal activation concept are proposed and compared. The most suitable model is selected for the work material, hardened AISI 52100 steel. The model prediction demonstrates excellent agreement with the hardness measurement on the specimens with isothermal or anisothermal treatments. For the isothermal treatments, the average prediction error, compared with the measured hardness, is 10.78kg∕mm2. As for the anisothermal treatments, the average error is 13.79kg∕mm2. The softening model provides a fundamental for the final prediction of material softening in hard turned surfaces.
The Influence of Sheet Metal Anisotropy on Laser Forming Process
Authors: Cheng Peng , Yao Y. Lawrence
Published: August 2005

Cold-rolled sheet metal that is often used in laser forming exhibits anisotropic properties, which are mostly caused by preferred orientations of grains developed during the severe plastic deformation such as cold rolling. In the present study, the textures of cold-rolled mild steel sheets are characterized and the influence of the plastic anisotropy on laser forming process is investigated. Deformation textures are measured in terms of pole figures and orientation distribution function (ODF) plots obtained through electron backscatter diffraction (EBSD). The anisotropy index (R-value) of the material with different rolling reductions is obtained by uniaxial tensile tests. Both are compared and agree with the texture development theory. Effects of the plastic anisotropy on bending deformation during the laser forming process are investigated experimentally and numerically. Various conditions including different laser power, scanning speed, and number of scans for sheets of different rolling reductions are considered and results are discussed. The simulation results are consistent with the experimental observations.
Experimental and Numerical Study of the Motions of a Turret Moored FPSO in Waves
Authors: Soares C. Guedes , Fonseca N. , Pascoal R.
Published: August 2005

This paper presents the results of an experimental program carried out with a model of a FPSO (Floating Production, Storage and Offloading) unit moored and subjected to incoming waves. In regular waves, a wide range of wavelengths were tested and the effect of the wave amplitude was also investigated. In irregular waves the model was subjected to different sea states, including very severe significant wave heights. The measured responses include the six degrees of freedom absolute motions, relative motions, and the mooring forces. The experimental data of surge, heave, and pitch is compared with calculated results from a Green’s function panel method and a strip theory program. In general, the agreement between experimental and numerical data is very good.
Methanol-Dependent Gene Expression Demonstrates that Methyl-Coenzyme M Reductase Is Essential in
Methanosarcina acetivorans
C2A and Allows Isolation of Mutants with Defects in Regulation of the Methanol Utilization Pathway
Authors: Rother Michael , Boccazzi Paolo , Bose Arpita , Pritchett Matthew A. , Metcalf W. W.
Published: August 2005

Methanosarcina acetivorans
C2A is able to convert several substrates to methane via at least four distinct methanogenic pathways. A common step in each of these pathways is the reduction of methyl-coenzyme M (CoM) to methane catalyzed by methyl-CoM reductase (MCR). Because this enzyme is used in each of the known pathways, the
mcrBDCGA
operon, which encodes MCR, is expected to be essential. To validate this prediction, a system for conditional gene inactivation was developed. A heterologous copy of the
mcrBDCGA
operon was placed under the control of the highly regulated
mtaC1
promoter, which directs the expression of genes involved in methanol utilization, and recombined onto the
M. acetivorans
chromosome. This allowed for disruption of the endogenous
mcr
operon in the presence of methanol. Because the
PmtaC1
promoter is transcribed only during growth on methanol,
mcrBDCGA
was rendered methanol dependent and the strain was unable to grow in trimethylamine media, strongly suggesting that
mcrBDCGA
is essential. Upon prolonged incubation, suppressed mutants which expressed
mcrBDCGA
constitutively could be selected. Expression analysis of
PmtaC1
::
uidA
gene fusions in several isolated suppressed mutants suggests that they carry
trans
-active mutations leading to deregulation of all genes under control of this promoter. Subsequently, proteome analysis of one such suppressed mutant revealed that all known proteins derived from
mtaC1
promoter-dependent expression were constitutively expressed in this mutant. This genetic system can therefore be employed for the testing of essential genes and for the identification of genes under a common regulatory mechanism by making regulatory mutations phenotypically selectable.
Upstream Migration ofXylella fastidiosavia Pilus-Driven Twitching Motility
Authors: Meng Yizhi , Li Yaxin , Galvani Cheryl D. , Hao Guixia , Turner James N. , Burr Thomas J. , Hoch H. C.
Published: August 2005

Xylella fastidiosais a xylem-limited nonflagellated bacterium that causes economically important diseases of plants by developing biofilms that block xylem sap flow. How the bacterium is translocated downward in the host plant's vascular system against the direction of the transpiration stream has long been a puzzling phenomenon. Using microfabricated chambers designed to mimic some of the features of xylem vessels, we discovered thatX. fastidiosamigrates via type IV-pilus-mediated twitching motility at speeds up to 5 μm min−1against a rapidly flowing medium (20,000 μm min−1). Electron microscopy revealed that there are two length classes of pili, long type IV pili (1.0 to 5.8 μm) and short type I pili (0.4 to 1.0 μm). We further demonstrated that two knockout mutants (pilBandpilQmutants) that are deficient in type IV pili do not twitch and are inhibited from colonizing upstream vascular regions in planta. In addition, mutants with insertions inpilBorpilQ(possessing type I pili only) express enhanced biofilm formation, whereas a mutant with an insertion infimA(possessing only type IV pili) is biofilm deficient.
The
agr
Radiation: an Early Event in the Evolution of Staphylococci
Authors: Wright Jesse S. , Traber Katrina E. , Corrigan Rebecca , Benson Sarah A. , Musser James M. , Novick Richard P.
Published: August 2005

agr
is a global regulatory system in the staphylococci, operating by a classical two-component signaling module and controlling the expression of most of the genes encoding extracellular virulence factors. As it is autoinduced by a peptide, encoded within the locus, that is the ligand for the signal receptor, it is a sensor of population density or a quorum sensor and is the only known quorum-sensing system in the genus.
agr
is conserved throughout the staphylococci but has diverged along lines that appear to parallel speciation and subspeciation within the genus. This divergence has given rise to a novel type of interstrain and interspecies cross-inhibition that represents a fundamental aspect of the organism's biology and may be a predominant feature of the evolutionary forces that have driven it. We present evidence, using a newly developed, luciferase-based
agr
typing scheme, that the evolutionary divergence of the
agr
system was an early event in the evolution of the staphylococci and long preceded the development of the nucleotide polymorphisms presently used for genotyping. These polymorphisms developed, for the most part, within different
agr
groups; mobile genetic elements appear also to have diffused recently and, with a few notable exceptions, have come to reside largely indiscriminately within the several
agr
groups.