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Lance–Adams syndrome is characterized by postural and action myoclonus occurring after hypoxic encephalopathy and thus called post-anoxic myoclonus. Most jerks are associated with abrupt muscle contraction, but abrupt falling of limbs or drop attacks caused by sudden lapses of muscle contraction (negative myoclonus) is also quite common. Most jerks originate from the primary motor cortex, but some jerks are induced via a brainstem reflex mechanism (reticular reflex myoclonus). Post-anoxic myoclonus is often resistant to the conventional medication, but anticonvulsants, including levetiracetam, can be effective.

In this paper, a control system for the influence of a time delay compensation using predictors and a disturbance observer is proposed. The time delay in the controlled plant is one of the serious problems decreasing the control stability. Therefore, many control methods for controlled plants with a time delay have been proposed until now. We proposed an effective control system for influence of time delay by connecting predictors and a disturbance observer to a PID control system. It alleviates the influence of the time delay on the target response and disturbance response.

Abstrac t—This paper describes dual sampling-late observer design for an auto operation robot. The proposed method has two sampling times to make the system more stability. For the plant, one depends on its sensor resolution. The other depends on the system. The former is longer than the latter. In this study, we could equalize the former to the latter with dual sampling-rate observer. In addition, the proposed method, which is used to realize the design, is discretized by a zero-order-hold, and works as a one-order-hold to increase the stability and simplify the design. In this study, we simulated three different sampling terms. Simulation results revealed the effectiveness of our proposed method.

Abstrac t—In this study, we propose a Sliding Mode Control (SMC) with a state predictor for time delay control systems. Time delay is a factor that causes instability in systems, and SMC is weakened by time delay. Therefore, we use a state predictor with SMC. State predictors are easily designed, and are suitable in combination with SMCs using the state of the plant as a controller. We have successfully realized control using a SMC with a state predictor for the plant with the time delay. In addition, we have confirmed the robustness of the proposed method. The proposed method shows the effective result compared with the conventional method in the simulation.

Laparoscopic gastrectomy (LG) is reported to be associated with faster recovery than open gastrectomy (OG); however, the influence of the surgical approach on initiation timing of adjuvant chemotherapy (AC) remains unclear.This was a single-institutional retrospective observational study. Patients with pathological stage II/III gastric cancer undergoing LG with D2 lymphadenectomy (LG group: n = 74) were matched 1:1 with patients selected from 214 similar patients undergoing OG (OG group: n = 74), identically matching gender, age, pathological stage, and type of gastrectomy, and comparing AC initiation timing between the two groups. Factors associated with delayed initiation of AC were investigated in a multivariable analysis.AC was performed in 86.5% (LG) and 83.8% (OG) of patients (p = 0.64). The median time interval before AC was significantly shorter in the LG vs. OG group (5.7 vs. 6.6 weeks, respectively, p 0.001), and significantly more patients received AC within 6 weeks (60.8% vs. 27.0%, p 0.001). Independent factors associated with delayed initiation of AC (6 weeks) were: morbidity (≥grade 3a; odds ratio (OR): 16.1, 95% confidence interval (CI): 1.86-143), open surgery (OR: 5.17, 95% CI: 2.50-13.1), and postoperative weight loss ≥ 8% (OR: 2.47, 95% CI: 1.07-5.71).LG may be associated with shorter intervals before AC. Postoperative morbidity should be reduced as much as possible.

The aim of the present study was to evaluate the effects of low-temperature degradation (LTD) induced by autoclaving on the mechanical and microstructural properties of tooth-colored 3 mol% yttria-stabilized tetragonal zirconia polycrystals (3Y-TZP). In total, 162 disc-shaped 3Y-TZP specimens were prepared. Two-thirds of the specimens were shaded by either the infiltration or powder mixing methods while the remaining specimens were used without coloring. The specimens were autoclaved at 134 °C for 0, 10, and 100 h to induce LTD (n=18 for each group). Chemical compositions were analyzed with X-ray fluorescence spectroscopy. Biaxial flexural strength was measured using a piston-on-three-ball test. The surface fraction and penetration depth of the monoclinic phase were examined using X-ray diffraction and scanning electron microscopy, respectively. The tooth-colored 3Y-TZP specimens contained Fe2O3 and Er2O3 (infiltration technique), and Fe2O3 (powder mixing method) at concentrations of

Thermal desorption of helium from Fe–9Cr and pure Fe which were irradiated with 5 keV He + ions at 85 or 473 K have been studied by thermal desorption spectrometry (TDS) at temperatures from room temperature to 1270 K and related microstructure changes by TEM. It is found that five TDS peaks appear in Fe–9Cr specimen and these peaks are well correlated with microstructure changes. From these results, the five peaks I Cr , II Cr , III Cr , IV Cr and V Cr may be attributed to release of trapped helium atoms by the break-up of vacancy–helium–self-interstitial atom complexes or very tiny loops, glide to the specimen surface or coalescence of interstitial type dislocation loops, shrinkage of dislocation loops, bubble migration to the specimen surface and α–γ phase transformation, respectively. Precipitation of Cr around the loops and bubbles in Fe–9Cr is revealed by STEM-EELS and this could shift the related TDS peaks to higher temperatures.

These In this paper, the control of the pneumatic actuator using Dahlin algorithm is proposed. Dahlin algorithm has problem which cause a steady-state error by an input-side disturbance for an integrator plant with time delay. In addition, it has problem which not ensure follow-up to a response model by parameter error of controller. To solve these problems, we introduce discrete-time IMC and iterative least squares technique. Our proposed method can remove a steady-state error caused by an input-side disturbance for an integrator plant with time delay by introducing discrete-time IMC and ensure follow-up to a response model by introducing iterative least squares technique. In the simulation, it is shown that the proposed method has a superior performance for an integrator plant with time delay. Furthermore, by applying the proposed method to a pneumatic actuator, the effectiveness of the method is examined and confirmed.

Myoclonus can be diagnosed and classified mainly based on clinical features. Neurophysiologic studies help confirm clinical diagnosis and classification, and understand underlying physiological mechanisms. The neurophysiologic classification of myoclonus is mainly based on surface EMG (individual EMG patterns, muscle spatial distribution and time sequence of muscle activation), EEG, EEG/EMG relationships (jerk-locked back-averaging, cortico-muscular coherence), somatosensory evoked potentials, and long-loop reflexes. Paired stimulation evoked response/long loop reflex and jerk-locked evoked responses evaluate the excitability changes of the primary somatosensory cortex. Transcranial magnetic stimulation can evaluate the excitability state of the primary motor cortex.

This is the first thorough study to evaluate the effects of age, gender, and stimulus side on the scalp topographies of somatosensory evoked potentials (SEPs) following stimulation of the posterior tibial nerve by using computerized bit-mapped color images and the significance probability mapping method. Seventy-four normal subjects whose ages ranged from 7 to 88 years were studied. Topographic mappings of most components in aged subjects were significantly different from those in young subjects, mainly because of higher amplitudes of the components in the aged group. However, scalp distribution of each component did not show a large difference among different age groups. There was a tendency that amplitudes in women were larger than those in men, and the gender differences of some components were significantly larger for some age groups. Stimulus side and handedness caused no significant difference in amplitudes and topographies of the components. These results were very similar to our previous results of the scalp topographies of SEPs following median nerve stimulation.

A disorder of the gracile axonal dystrophy (GAD) mutant mouse is characterized by a neuro-muscular disease with sensory ataxia (detectable 30 days after birth) and paresis of the hind-limbs (detectable at 80 days). In the sensory ataxia stage, histological study of the primary sensory system shows that, in addition to the lesions in the central nervous system, peripherally projecting axons have also started to degenerate at their distal ends in muscle spindles. Although the structure of Ia fibre endings appear normal until 15 days after birth, initial changes in the annulo-spiral structure are detected around the 20th day by a degeneration of the terminal axons. Degeneration then progressed proximally and the secondary endings also start to degenerate. Neuron cell bodies located in the dorsal root ganglia are morphologically intact until the later stages. Chronological studies indicate that, although axonal degeneration progresses throughout life, it is accentuated during the rapid somatic growth period. Around 50 days of age, transient regeneration takes place at axonal endings when somatic growth has attained a plateau. Such primary sensory endings tend to be restored by fine, multiple axons which gain access to the intrafusal fibres through the original endoneurial tubes. Ultrastructural observations at the fully affected stage show intrafusal muscle fibres lying scattered within spindles due to loss of the fine network of inner capsule layers and an almost complete loss of sensory endings from the surface of intrafusal muscle fibres. These results indicate that this mutant mouse is a useful model for naturally occurring ‘dying back’ type axonal degeneration or ‘central and peripheral distal axonopathies', and would provide significant information about the complete evolution of the pathological processes involved.

L-Histidine labeled with deuterium at the C-5' position of the imidazole ring, L-[5'-2H]histidine (His-5'-D), was used as a probe for investigating a stepwise reversible mechanism via a carbanion intermediate in the elimination of ammonia catalyzed by histidine ammonia-lyase (EC 4.3.1.3). The labeled L-histidine (His-5'-D) (2.45 mM) was incubated with histidine ammonia-lyase (200 units) from Pseudomonas fluorescens at pH 7.0 or 9.0 at 25.0 degrees C for 24 h. The time course of the reaction was examined to determine the rates of enzyme-catalyzed hydrogen exchange at C-5' of L-histidine and urocanic acid. The finding of the enzyme-catalyzed hydrogen exchange at C-5' of both L-histidine and urocanic acid in the presence of L-histidine provided a rational explanation for a stepwise reversible mechanism via a carbanion intermediate in the elimination reaction. The rate of increase in the concentration of urocanic acid exchanged with hydrogen (UA-5'-H) did not depend on the formation rate of urocanic acid and UA-5'-H was continuously formed at a constant rate (25.6 microM/h) even after the completion of urocanic acid formation. These observations suggested the presence of the reversible reaction of urocanic acid and a carbanion intermediate. Since there was only a minor contribution for the formation of UA-5'-H from L-histidine exchanged with solvent hydrogen (His-5'-H), the main pathway in the enzymatic reaction of His-5'-D must be the formation of UA-5'-D via a carbanion intermediate (carbanion-D). Regeneration of the carbanion-D from UA-5'-D by its reverse reaction and subsequent hydrogen incorporation at C-5' would contribute to a large extent for the formation of UA-5'-H. The stability of carbanion was also demonstrated to be approximately three times higher at pH 7.0 than at pH 9.0.

For improved establishment of the dynamical reference frame and tying it to the stellar reference frame, a method to observe close approach (CA) events between satellite and satellite and/or satellite and star is proposed here. The accuracy of measurements of angular distance is 0”.02 – 0”.03 for a single data point. We apply this technique fairly successfully to the CA events of the Galilean satellites and a preliminary orbital longitude correction to the E2X3 constants of J4 is obtained from eight CA observations ranging from 1987 to 1989.

This paper proposes a real time evaluation method for different types of bio-neurological signals. In this method, multiple types of bio-neurological signals can be automatically processed in a single system in real time, including EEG, EMG, EOG, etc. It can display the wave shapes of these signals, calculate the feature parameters, indicate various kinds of artifacts contaminating in the signals, and so on. Therefore, this method not only can pre-process raw bio-neurological signals online, but also can evaluate the signals based on the user's requirement. The output of qualified bio-neurological signals can be possibly adopted to assist doctors to interpret bio-neurological signals for judging the diseases or providing any suggestions to subjects. This method can be functionally extended according to the requirement from users.

Quasi phase-matching (QPM) is an attractive technique for optical wavelength conversion applications instead of the conventional birefringent phase matching. An advantage of the QPM is that any interaction within the transparency range of the material can be noncritically phase matched at a specific temperature by using the largest nonlinear optical coefficient. The periodically poled lithium niobate (PPLN) has been extensively used for the quasi phase-matched optical parametric oscillator (QPM-OPO). The effective nonlinear coefficient of the PPLN is 21.6 pm/V and enables one to realize efficient wavelength conversion. Usually the wavelength tuning of the QPM-OPO is achieved by changing the crystal temperature. Although the wide wavelength tuning range is achieved with the temperature tuning, the response is not fast. In this paper we demonstrate the wavelength tuning of the QPM-OPO by the electro-optic effect for fast wavelength tuning.

We here reported a 54-year-old female patient with Crow-Fukase syndrome associated with pulmonary plasmacytoma. She was found to have scattered tumor in 1990. Although the tumor had slowly grown for the last 10 years, she showed no clinical symptoms. Numbness and weakness of lower extremities began in June 1999, and she was referred to Kyoto University Hospital on Oct. 21 1999 for evaluation of progressive symptoms. She had skin pigmentation, edema of the lower extremities, lymphadenopathy, muscle weakness and sensory disturbance in a glove-and-stocking distribution. Serological examination showed monoclonal IgG-lambda gammopathy. Serum vascular endothelial growth factor (VEGF) was markedly elevated. Microscopic studies on biopsied sural nerve demonstrated mild decrease of myelinated fibers. Immunohistochemically, the pulmonary tumor was defined as an IgG (lambda type) plasmacytoma. After treatment with melphalan-prednisolone therapy, the neurological symptoms improved along with decrease of serum VEGF levels as well as the size of pulmonary plasmacytoma. This is the first report of a patient with Crow-Fukase syndrome associated with pulmonary plasmacytoma. This case suggests that growth of pulmonary plasmacytoma might have played an important role in the overproduction of VEGF and thus development of Crow-Fukase syndrome.

Two functional brain-mapping techniques, functional magnetic resonance imaging (fMRI) and cortical stimulation by chronically implanted subdural electrodes, were used in combination for presurgical evaluation of three patients with intractable, partial motor seizures. Brain mapping was focused on characterizing motor-related areas in the medial frontal cortex, where all patients had organic lesions. Behavioral tasks for fMRI involved simple finger and foot movements in all patients and mental calculations in one of them. These tasks allowed us to discriminate several medial frontal motor areas: the presupplementary motor areas (pre-SMA), the somatotopically organized SMA proper, and the foot representation of the primary motor cortex. All patients subsequently underwent cortical stimulation through subdural electrodes placed onto the medial hemispheric wall. In each patient, the cortical stimulation map was mostly consistent with that patient's brain map by fMRI. By integrating different lines of information, the combined fMRI and cortical stimulation map will contribute not only to safe and effective surgery but also to further understanding of human functional neuroanatomy.

We performed long-term video/ EEG monitoring and a single photon emission computed tomographic (SPECT) study to clarify generating mechanism of bilateral tonic motor seizures resembling seizures generated by the supplementary motor area (SMA), in patients with bilateral parietal lesions. We describe 2 patients (age 24 and 32 years), with bilateral parietal lesions. Clinically, seizures were preceded by lightning sensation in the body, followed by asymmetric tonic posturing of both hands and thrashing movements of the feet, lasting for less than 1 min. Ictal rhythmic (7-15 Hz) activity at the vertex was observed on the EEG in 1 patient. Interictal SPECT in 2 patients showed decreased blood flow in both parietal areas, consistent with bilateral parietal abnormalities on T2- and T1-weighted MRIs. Ictal SPECT in 1 patient showed increased blood flow in the right parietal and frontopolar areas. The present 2 patients had clinically asymmetric tonic seizures, most likely resulting from spreading of the ictal activity from the parietal lesions via the superior longitudinal fasciculus to the SMA. Bilateral, homologous lesions in the parietal area might cause disinhibition on the unilateral epileptogenic side.

In order to help clarify the mechanism of tonic convulsion, which is commonly seen in supplementary motor area (SMA) seizures, we investigated the temporal relationship between ictal discharges arising from the SMA and the associated EMG discharges in the foot, in a patient with SMA seizures, prior to surgical treatment. The patient's intractable seizures consisted of tonic followed by clonic convulsion of the left foot also involving at times, the left hand. Ictal EEGs were investigated by subdural electrodes placed on the SMA-proper and pre-SMA, which were defined by cortical stimulation and by recording cortical-evoked potentials. Interictally, repetitive spike discharges were seen at the pre-SMA. Each seizure initially had a tonic phase associated with an electrodecremental EEG pattern. It was followed by clonic convulsion as shown by clonic EMG discharges of the left tibialis anterior (TA) muscle. It had a duration of 300 to 500 msec, and on each occasion a positive cortical activity at the pre-SMA preceded the EMG onset by 110 msec, and a negative spike at the SMA-proper preceded the EMG onset by 50 to 60 msec. Epileptic discharges originating from the pre-SMA spread to the SMA-proper and possibly also to the primary motor cortex (MI) in this patient. Since both SMA-proper and MI could elicit EMG discharges through the independent corticospinal tracts having different conduction velocities, even a single spike arising from the SMA could give rise to a long EMG burst, which may play some role in the tonic convulsion which characterizes SMA seizures.

A clinically tonic seizure phase, immediately followed by psychomotor features (right hand dystonic posture, left hand and oral automatisms), was recorded by video and EEG, in a patient who had gliosis of the left temporal lobe and left hippocampal atrophy. Interictal epileptiform discharges were frequently seen in the left temporal area, and at the time of the tonic seizure phase, ictal spike discharges were continuously observed at the left posterior temporal area, which was recognized only by applying a high frequency filter (HFF) of 15 Hz to the digitally recorded EEG because EMG artifacts totally obscured the EEG with a HFF of 60 Hz. It is most likely that tonic seizure can occur in an adult patient with temporal lobe epilepsy, and it is speculated that an epileptogenic focus might activate a certain brain area which is regarded as a symptomatogenic zone for tonic seizures. If the tonic seizure phase is immediately followed by psychomotor features as seen in the present patient, the former could be due to focal epilepsy.

A case of membranous lipodystrophy (Nasu-Hakola disease; NHD) associated with palilalia was reported. A 38-year-old Japanese woman developed walking difficulty in her twenties. At age 35 she manifested neuropsychiatric symptoms characterized by euphoria, palilalia and dementia. A bone marrow biopsy showed periodic acid Schiff-positive membranous cystic lesions in the adipose tissue. Positron emission tomography with (18F)-2-fluoro-2-deoxy-D-glucose disclosed that regional cerebral glucose metabolism was decreased in the bilateral frontal white matter with mild hypometabolism in the thalamus and basal ganglia; all predominantly on the right. Taken together with the previous postmortem findings, it is postulated that frontal lobe hypofunction, predominantly in the right hemisphere, produced the unique neuropsychiatric symptoms in this patient.

To examine the neuropsychological mechanisms involved in writing kanji (morphograms), we used functional MRI (fMRI) in 10 normal volunteers, all right-handed, native Japanese speakers. The experimental paradigms consisted of kana-to-kanji transcription, mental recall of kanji orthography and oral reading and semantic judgement of kana words. The first two tasks require manual and mental transcription of visually presented kana words into kanji, respectively, whereas the last two tasks involve language processing of the same set of stimulus words without recall of kanji. The transcription and mental recall tasks yielded lateralized activation of the left posterior inferior temporal cortex (PITC). By contrast, neither oral reading nor semantic judgement produced similar activation of the area. These results, in good accordance with lesion data, provide converging evidence that the left PITC plays an important role in writing kanji through retrieval of their visual graphic images, and suggest language-specific cerebral organization of writing. The set of fMRI experiments also provides new neuroimaging data on the cortical localization of basic language functions in people using a non-alphabetical language.

A method for estimating the physiological variability of peak latency in an evoked potential, of whom the peak latency and amplitude varied, by using the property of asynchronous averaging was proposed. A point estimate of the physiological variability was obtained by minimizing the mean square error between a standard waveform and the asynchronously averaged waveform. An interval estimate was obtained by using the relationship between the signal-to-noise ratio and the standard deviation of the point estimate for the variability of peak latency. The proposed method was evaluated by using simulation data, and was successfully applied to actual P300 data of six normal subjects. The method gave accurate estimates for the physiological variability of peak latency of P300, and would also be effectively applicable to any other evoked potential records for estimating the physiological variability.

Single photon emission computed tomography was used to evaluate regional cerebral blood flow changes during gait on a treadmill in 10 patients with Parkinson's disease and 10 age-matched controls. The subjects were injected with [99mTc]hexamethyl-propyleneamine oxime twice: while walking on the treadmill, which moved at a steady speed, and while lying on a bed with their eyes open. On the treadmill, all subjects walked at the same speed with their preferred stride length. The patients showed typical hypokinetic gait with higher cadence and smaller stride length than the controls. In the controls, a gait-induced increase in brain activity was observed in the medial and lateral premotor areas, primary sensorimotor areas, anterior cingulate contex, superior parietal cortex, visual cortex, dorsal brainstem, basal ganglia and cerebellum. The Parkinson's disease patients revealed relative underactivation in the left medial frontal area, right precuneus and left cerebellar hemisphere, whereas they showed relative overactivity in the left temporal cortex, right insula, left cingulate cortex and cerebellar vermis. This is the first experimental study showing that the dorsal brainstem, which corresponds to the brainstem locomotor region in experimental animals, is active during human bipedal gait. The reduced brain activity in the medial frontal motor areas is a basic abnormality in motor performance in Parkinson's disease. The underactivity in the left cerebellar hemisphere, in contrast to the overactivity in the vermis, could be associated with a loss of lateral gravity shift in parkinsonian gait.

A 25-year-old man manifesting gelastic seizure in association with hypothalamic hamartoma was reported. The epileptogenic focus was evaluated by long-term video EEG monitoring, single photon emission computed tomography (SPECT) and positron emission tomography (PET). Multiple independent ictal foci were found in the ictal EEG recording, and glucose metabolism and cerebral blood flow were decreased in scattered cortical areas. Facial asymmetry seen during gelastic seizure in this case may be caused by contraction of mimetic contralateral to the ictal focus in the temporal lobe.

A 58-year-old woman developed slowly progressive tremulous myoclonus provoked mainly by action and posture. She had neither seizure nor dementia. No one in her family had similar symptoms. The presence of giant somatosensory evoked potentials (SEP) with enhanced long loop reflex and premovement cortical spikes demonstrated by the jerk-locked averaging method suggest that the involuntary movement is cortical reflex myoclonus. Magnetoencephalogram revealed that the generator sources of giant SEPs were the post-central somatosensory cortex and probably also the pre-central motor cortex. Symptoms improved after treatment with zonisamide, clonazepam and valpolate. This kind of involuntary movement might be called cortical myoclonic tremor.

A 23-year-old, right handed women has suffered from supplementary motor seizures manifesting tonic followed by clonic contractions of the left foot, occasionally spreading to the left hand and trunk, since the age of 7 years. The mean frequency of seizures on admission was about 10 times per day. A brain MRI showed an abnormal intensity area about 3 cm in diameter in the right mesial frontal lobe involving the superior frontal and cingulate gyri. Six habitual seizures were recorded during long-term monitoring with digital EEG segments time-locked to the clonic contractions of the left foot, a negative spike was detected about 50 ms before the EMG onset at the midline fronto-central area slightly lateralized to the left. In the focal motor seizure arising from the mesial frontal lobe like in the present case, jerk-locked back averaging helps detecting the epileptiform activity which is otherwise undetectable.

An auditory-evoked magnetic field was recorded before and during tinnitus remission induced by an intravenous lidocaine injection. One and 4 kHz probe tones were presented monaurally in four tinnitus patients, and the responses were recorded using a 122-channel magnetometer. Three normal volunteers were also examined as controls. In tinnitus patients, the N100 m peak became sharper, while there was no marked change except for slight reduction in amplitude in normal subjects. Tinnitus remission by lidocaine may be related to attenuation of a masking-like effect of tinnitus on the sound-evoked responses.

Sixty patients with disabling myoclonus excluding mainly spinal myoclonus were treated by piracetam as an open-labeled study, and myoclonus score, neurological symptoms, functional disability, and intensity of myoclonus were scored before and after treatment, including a blinded video inspection. Electrophysiological correlation also was investigated before and after treatment. Piracetam was effective in myoclonus, especially that of cortical origin, in both monotherapy and polytherapy. Piracetam also had positive benefits on gait ataxia and convulsions but not on dysarthria, and feeding and hand writing improved much more significantly. Psychologically significant improvement was seen in decreased motivation, sleep disturbance, attention deficit, and depression, all of which might be possibly secondary benefits associated with improvement of myoclonus. There was no positive correlation between clinical and electrophysiological improvement. Tolerance was good, and side effects were transient. However, hematological abnormalities observed in at least two patients in the present study should be kept in mind when relatively large doses of piracetam are administered, especially in combination with other antimyoclonic drugs.

We reported a 25-year-old man with intractable right temporal lobe epilepsy in whom subdural recording successfully delineated the epileptogenic area in the right anterior mesial to basal temporal region in spite of the presence of a postoperative lesion in the right posterior temporal region. The patient underwent right posterior temporal resection due to ependymoma at the age of 8 years. Since age 19, he had suffered from medically intractable psychomotor seizures. Ictal scalp-recorded EEG suggested an epileptogenic area at the right temporal area, but it could not specifically demarcate the site because of bone deficits from the previous surgery. Ictal SPECT showed a hyperactive area in the right anterior temporal area, which was inconsistent with the MRI finding. In case of partial epilepsy associated with structural lesion like in the present case, if results of various non-invasive studies are discrepant as to the epileptogenic area, invasive studies using, for example, subdural EEG monitoring is necessary to determine the responsible area.

A 27-year-old Japanese woman was admitted to Kyoto University Hospital because of gait disturbance since age 25. Her elder sister had been suffering from childhood-onset dystonia-parkinsonism with diurnal fluctuation which initially responded well to levodopa therapy, but later larger dose of levodopa was needed because of severe treatment-related fluctuation of the clinical symptoms. Physical examination revealed left foot dystonia, mild parkinsonism with kinesie paradoxale and dyskinesia of lower limbs. Symptoms were relieved by sleep and worsened by walking. Laboratory data including serum ceruloplasmin, serum and urinary amino acid analysis, and hexosaminidase and beta-glucosidase activity in leukocytes were all normal. Homovanillic acid (HVA) in cerebrospinal fluid was normal (68 ng/ml) at 8 pm but markedly decreased (7 ng/ml) at 4 pm. Cranial MRI was normal. 18F-6-fluorodopa PET demonstrated decreased dopa uptake in the bilateral striatum, especially in the putamen. 18F-fluoro-2-deoxyglucose PET showed decreased regional glucose metabolism in the bilateral putamen. Levodopa therapy rendered equivocal effects while trihexyphenydil was effective. This case indicated that some cases of dopa-unresponsive dystonia with parkinsonism might be a clinical variant of juvenile parkinsonism. 18F-6-fluorodopa PET is useful in evaluating juvenile dystonia-parkinsonism, though it may not predict levodopa effectiveness. 18F-fluoro-2-deoxyglucose PET study will be helpful in predicting the effect of levodopa therapy, because decreased regional glucose metabolism in the putamen probably indicates poor response to levodopa. Further study including dopaminergic receptor imaging study is needed to clarify the physiological mechanism of co-existing dystonia and parkinsonism in patients with juvenile parkinsonism and related disorders.

The pharmacokinetics of L-histidine in humans has been investigated to evaluate the in vivo histidine ammonia lyase system for the conversion of L-histidine to urocanic acid. Two healthy volunteers (subjects A and B) received a single 100-mg oral dose of L-[3,3-2H2,1',3'-15N2]histidine. Blood and urine samples were obtained over 24 hr after the administration and analyzed by stable isotope dilution ms. Labeled L-histidine was rapidly absorbed, and a maximum plasma concentration of L-histidine was observed at 30 min (1057.6 ng/ml) in subject A and at 60 min (1635.6 ng/ml) in subject B after oral administration. Pharmacokinetic parameters were calculated based on a two-compartment model. Labeled L-histidine in subject A (t1/2 = 1.0 hr) was eliminated approximately twice faster than that in subject B (t1/2 = 1.9 hr). Total body clearances were 70.0 liters/hr in subject A and 30.0 liters/hr in subject B. The low ratios of the renal clearance to the total body clearance (1.04% for subject A and 0.43% for subject B) indicated that most of L-histidine was eliminated via the nonrenal processes. L-Histidine was rapidly metabolized to urocanic acid. Maximum plasma concentrations of urocanic acid were 59.61 ng/ml at 30 min for subject A and 46.10 ng/ml at 60 min for subject B. The slope of the plot of urinary excretion rate of urocanic acid vs. the plasma concentration of unchanged L-histidine was demonstrated to reflect the metabolic clearance of L-histidine to urocanic acid. The method of evaluating the in vivo human histidine ammonia lyase activities discussed in this study offers a significant value with regard to the biochemical and clinical elucidations of the heterogeneity of histidinemia.

Voluntary movements can be classified into the two categories depending on how those are initiated; ones initiated internally, and others triggered or paced by external stimuli. Central neuronal mechanisms involved in those preparation and execution could be represented by movement-related cortical potentials (MRCP) or Bereitschaftspotential (BP), and contingent negative variation (CNV), respectively. The both potentials, as the field potentials, can be recorded with long time constant, and represent transient changes of the membrane potentials of the cortical neurons. In patients with the lesion at the cerebellar efferent system, the BP disappeared completely whereas the late CNV was normally seen. In patients with parkinsonism, in contrast, the late CNV was significantly smaller in amplitude in severe than in mild symptom group. Recent subdural recording in epilepsy patients demonstrated that the BP and late CNV were commonly generated from the primary and supplementary motor areas, and that late CNV also arose from the frontal association cortices (mesial, basal and lateral prefrontal areas). It is therefore suggested that subcortical generating mechanism is different for the late CNV and BP although both commonly share at least some cortical generators, and that the basal ganglia are most likely responsible for the generation of the late CNV and the cerebellar efferent system for the generation of the BP.

Cortical myoclonus (CM) and focal dystonia (FD) are commonly characterized by co-contraction of agonist and antagonist muscles, enhancement by intentional movement, strong influence by sensory input, and spread to adjacent muscles. On the other hand, they are different in the nature of movements, speed of muscle contraction, speed of spread, and drug effects. There are abundant data indicating that CM is due to pathological hyperexcitability of the sensorimotor cortex (S1-M1), while, in FD, no definitive evidence to suggest cortical hyperexcitability has been found. Changes in regional cerebral blood flow (rCBF) studied by positron emission tomography (PET) during movements in patients with dystonia were inconsistent with regard to S1-M1, but the frontal cortex including the rostral SMA was shown to be overactivated, suggesting the thalamocortical disinhibition based on the basal ganglia disorders.