Sang-Doe Yi

Material-specific memory in temporal lobe epilepsy: Effects of seizure laterality and language dominance

This study investigated the effects of seizure laterality and language dominance on material-specific memory in temporal lobe epilepsy (TLE). Left TLE (LTLE) patients with left-hemisphere language dominance (LHLD) showed significantly higher nonverbal than verbal memory capacity, whereas right TLE patients with LHLD showed significantly better verbal than nonverbal memory capacity. LTLE patients with non-left-hemisphere language dominance (NLHLD) showed significantly better verbal memory capacity compared with LTLE patients with LHLD. Thus, selective verbal or nonverbal memory deficits that are dependent on side of seizure onset were apparent in patients with LHLD but not in patients with NLHLD. Relative sparing of verbal memory capacity in LTLE patients with NLHLD may reflect interhemispheric reorganization of verbal memory function.

Pregabalin add-on therapy using a flexible, optimized dose schedule in refractory partial epilepsies: a double-blind, randomized, placebo-controlled, multicenter trial.

Purpose:  To evaluate the efficacy and safety of pregabalin (PGB) as adjunctive therapy, using a flexible‐dosing schedule in Korean patients with refractory partial‐onset seizures.

NGFI-C expression is affected by physiological stimulation and seizures in the somatosensory cortex

NGFI-C is an early response gene which encodes a Cys2/His2 zinc finger protein. NGFI-C has previously been demonstrated to be inducible in PC12 cells after NGF stimulation. This study sought to localize this gene in somatosensory cortex, and investigate its possible induction by physiological and seizure stimuli. To determine if NGFI-C message levels are affected by stimulation, RT-PCR was performed on mRNA extracts from somatosensory cortex. NGFI-C mRNA levels were increased to levels four-fold over baseline after a seizure. In a paradigm used as a model of experience-dependent plasticity, vibrissae stimulation also increased the level of NGFI-C expression in the contralateral barrel cortex to 180% of control levels. In situ analysis using digoxigenin-labelled cRNA probes demonstrated NGFI-C containing neurons throughout layers 2 through 6 in somatosensory cortex. A higher cell density was seen after stimulation. Qualitatively, staining was more intense in post-seizure and post-stimulus cortex than in control cortex. Analysis of related zinc finger expression in serial sections revealed that NGFI-C is expressed in a distinct but overlapping cell populations relative to NGFI-A, Krox 20, and Egr-3. These studies demonstrate the inducible nature of NGFI-C message in response to a physiological vibrissae stimulus, as well as to seizures. However, the levels and pattern of expression differ between these two stimuli.

Differential effects of left versus right mesial temporal lobe epilepsy on Wechsler intelligence factors.

This study investigates the effects of left versus right mesial temporal lobe epilepsy (MTLE) on Wechsler intelligence factors. In the left MTLE group, the Verbal Comprehension (VC) factor score was significantly lower than the Perceptual Organization (PO) factor score, whereas in the right MTLE group, the PO factor score was significantly lower than the VC factor score. The VC factor score was significantly lower for the left than the right MTLE group, whereas the PO factor score was significantly lower for the right than the left MTLE group. Thus, left versus right MTLE was associated with relative deficits in verbal versus nonverbal intelligence, respectively. These findings indicate that lateralized cognitive deficits in unilateral MTLE patients are not limited to the learning-memory domain but include more global intelligence functions.

Lateralization of epileptic foci by neuropsychological testing in mesial temporal lobe epilepsy

This study investigated the lateralizing value of neuropsychological testing in presurgical evaluation of mesial temporal lobe epilepsy (MTLE). This study differed from previous ones in that the cutoff values were determined to yield high positive predictive values (PPVs), multiple neuropsychological predictors were considered in combination, and patients with atypical language dominance or low intelligence were not excluded from the sample. The participants were 92 patients with MTLE (left, n = 47; right, n = 45) who showed good postoperative seizure control. With a stringent cutoff criterion, the multiple neuropsychological predictors considered in combination yielded a sensitivity of 15% and a PPV of 93%, and with a less stringent cutoff criterion, a sensitivity of 37% and a PPV of 83%.

Inhibitory effects of glucosamine on lipopolysaccharide-induced activation in microglial cells

1. The aim of the present study was to investigate the effects of glucosamine on lipopolysaccharide (LPS)‐induced cellular activation in microglia and to evaluate the inhibitory mechanisms involved.

Autosomal dominant nocturnal frontal lobe epilepsy and mild memory impairment associated with CHRNB2 mutation I312M in the neuronal nicotinic acetylcholine receptor

Certain paroxysmal nocturnal behaviors have been established as features of nocturnal frontal lobe epilepsy (NFLE). Despite insight into its genetics, the majority of patients with NFLE are not linked to a known mutation and clinical diagnosis remains a challenge. We describe a family presenting with stereotyped nocturnal arousals from non-rapid eye movement sleep, bilateral hand posturing, and pelvic thrusting in the mother, but subtle motor activity in the daughter, and minimal or no epileptiform EEG discharges. Despite normal IQ, there were moderate and severe verbal memory deficits in the mother and daughter, respectively. Genetic testing revealed the CHRNB2 mutation I312M in transmembrane region 3 (M3) of the neuronal nicotinic acetylcholine receptor. Phenotypic similarities in unrelated families suggest the determining role of this mutation in NFLE, whereas different inter- and intrafamilial cognitive profiles point to other factors. The absence of clear motor features of NFLE in the daughter emphasizes the shortcomings of current clinical criteria and the potential for genetic testing to further guide clinical diagnostic criteria.

Lateralizing value of the Wada memory test in non-Western patients with temporal lobe epilepsy

The Wada memory test measures a psychological construct (i.e. memory), which is widely acknowledged to be under the influence of a vast array of moderating variables including culture. Thus, the lateralizing value of the Wada memory test for epileptogenic foci may potentially differ for Western versus non-Western patients with temporal lobe epilepsy (TLE). In the present study, the lateralizing value of the Wada memory test was investigated in 17 Korean patients with medically intractable TLE who were post-operatively seizure-free. The Wada memory stimuli were composed of eight drawings of common objects, animals, and fruits. A clinical criterion of at least 2 points difference between left and right injections correctly classified 14 patients (82%) into left and right TLE groups, with only one patient (6%) falsely classified. This diagnostic accuracy is at least as high as that reported for Western TLE patients. These results indicate that whatever culture-specific factors Korean TLE patients may bring to the Wada memory test, they do not significantly reduce the lateralizing value of the test.

Unblinded, randomized multicenter trial comparing lamotrigine and valproate combination with controlled-release carbamazepine monotherapy as initial drug regimen in untreated epilepsy

PURPOSE To compare controlled-release carbamazepine monotherapy (CBZ-CR) with lamotrigine and valproate combination therapy (LTG + VPA) in equivalent total drug load, as initial drug regimen in untreated patients with partial and/or generalized tonic-clonic seizures (GTCS). METHODS This unblinded, randomized, 60-week superiority trial recruited patients having two or more unprovoked seizures with at least one seizure during previous three months. After randomization into CBZ-CR or LTG + VPA, patients entered into eight-week titration phase (TP), followed by 52-week maintenance phase (MP). Median doses of CBZ-CR and LTG + VPA were 600 mg/day and 75 mg/day + 500 mg/day, respectively. Primary outcome measure was completion rate (CR), a proportion of patients who have completed the 60-week study as planned. Secondary efficacy measures included seizure-free rate (SFR) for 52-week of MP and time to first seizure (TTFS) during MP. RESULTS Among 207 randomized patients, 202 underwent outcome analysis (104 in CBZ-CR, 98 in LTG + VPA). CR was 62.5% in CBZ-CR and 65.3% in LTG + VPA (p = 0.678). SFR during MP was higher in LTG + VPA (64.1%) than CBZ-CR (47.8%) (P = 0.034). TTFS was shorter with CBZ-CR (p = 0.041). Incidence of adverse effects (AEs) were 57.7% in CBZ-CR and 60.2% in LTG + VPA and premature drug withdrawal rates due to AEs were 12.5% and 7.1%, respectively, which were not significantly different. CONCLUSION CR was comparable between LTG + VPA and CBZ-CR, however, both SFR for 52-week MP and TTFS during MP were in favor of LTG + VPA than CBZ-CR. The study suggested that LTG + VPA can be an option as initial drug regimen for untreated patients with partial seizures and/or GTCS except for women of reproductive age.

P3-193: The utility of the verbal fluency test in early stage of Alzheimer's disease: Preliminary study

Results: Mean age for total sample was 68.4 (SD 6.4) and mean educational level was 12.2 (SD 5.4). 41.2% of participants spontaneously referred being worried about memory, whereas 65.2% indicated some level of memory concern in the checklist, which suggests that assessment methods impact data on memory complaints. Analyses comparing spontaneous complainers (SC) and non-complainers (SNC) at baseline revealed no significant differences for cognitive performance variables (RBMT, FOME, SKT, Verbal Fluency, Trails A and B). At 24-month follow up, no significant differences were found for cognitive measures between SC and SNC. onclusions: In this sample, presence of memory complaints at baseline did not differentiate performance levels.