Estimation of External Contamination and Exposure Rates Due to Fission Product Release

In the event of a radiological incident, the release of fission products into the surrounding environment and the ensuing external contamination present a challenge for triage assessment by emergency response personnel. Reference exposure rate and skin dose rate calibration data for emergency response personnel are currently lacking for cases where receptors are externally contaminated with fission products. Simulations were conducted to compute reference exposure rate coefficients and skin dose rate coefficients from photon-emitting fission products of radiological concern. To accomplish this task, simplified mathematical skin phantoms were created using surface area and height specifications from International Commission on Radiological Protection Publication 89. Simulations were conducted using Monte Carlo radiation transport code using newborn, 1-y-old, 5-y-old, 10-y-old, 15-y-old, and adult phantoms for 22 photon-emitting radionuclides. Exposure rate coefficient data were employed in a case study simulating the radionuclide inventory for a 17 × 17 Westinghouse pressurized water reactor, following three burn-up cycles at 14,600 MWd per metric ton of uranium. The decay times following the final cycle represent the relative activity fractions over a period of 0.5-30 d. The resulting data can be used as calibration standards for triage efforts in emergency response protocols.

Brain allopregnanolone induces marked scratching behaviour in diet-induced atopic dermatitis mouse model

Allopregnanolone (ALLO) is a neurosteroid produced in the brain, but so far, no study has explored its link with itching. Herein, we used a diet-induced atopic dermatitis mouse model to examine whether exogenously administered and endogenously produced ALLO contribute to inducing scratching. Systemic administration of ALLO elicited robust scratching in the atopic dermatitis model, while it did not affect spontaneous and pruritogen-induced scratching in normal mice. ALLO caused scratching when administered intracisternally, but not when administered intrathecally or intradermally, suggesting the involvement of supraspinal mechanisms. Pharmacological analyses suggested that both γ-aminobutyric acid type A receptor activation and serotonin type 3 receptor inhibition were involved in ALLO-induced scratching. We next examined whether endogenously produced ALLO is involved in ethanol-induced scratching in atopic dermatitis mice, because ethanol administration increases ALLO in rodent brain. Acute ethanol administration increased brain ALLO levels, which coincided with increased scratching. Pre-treatment with finasteride, a synthetic ALLO inhibitor, suppressed ethanol-induced scratching and ALLO production in the brain. Collectively, our results demonstrated for the first time that ALLO administration caused marked scratching in atopic dermatitis mice, and ethanol-induced scratching may be mediated through endogenously produced brain ALLO.

Direct brain recordings reveal prefrontal cortex dynamics of memory development

Prevailing theories link prefrontal cortex (PFC) maturation to the development of declarative memory. However, the precise spatiotemporal correlates of memory formation in the developing brain are not known. We provide rare intracranial evidence that the spatiotemporal propagation of frontal activity supports memory formation in children. Seventeen subjects (6.2 to 19.4 years) studied visual scenes in preparation for a recognition memory test while undergoing direct cortical monitoring. Earlier PFC activity predicted greater accuracy, and subsecond deviations in activity flow between subregions predicted memory formation. Activity flow between inferior and precentral sites was refined during adolescence, partially explaining gains in memory. In contrast, middle frontal activity predicted memory independent of age. These findings show with subsecond temporal precision that the developing PFC links scene perception and memory formation and underscore the role of the PFC in supporting memory development.

Acetylacetonato-based pincer-type nickel(ii) complexes: synthesis and catalysis in cross-couplings of aryl chlorides with aryl Grignard reagents

In this work, three different types of acetylacetonato-based pincer-type nickel(ii) complexes (2) were prepared. Complex 2a possessed the tridentate ONN ligand, which was constructed by the condensation reaction of acetylacetone with N,N-diethylethylenediamine. Complex 2b contained the PPh2 donor group in contrast to the NEt2 group in 2a, i.e., an ONP ligand framework. Complex 2c was composed of the NNN ligand, which was prepared by the reaction of 4-((2,4,6-trimethylphenyl)amino)pent-3-en-2-one with N,N-diethylethylenediamine. In addition to X-ray diffraction analysis, these complexes were characterized spectroscopically. Their catalytic activity for a cross-coupling reaction of aryl halides with aryl Grignard reagents was also evaluated. Among these complexes, 2b acted as an effective catalyst for the cross-coupling reaction using aryl chlorides as electrophiles. The electronic properties of these Ni(ii) complexes were investigated by cyclic voltammetry and density functional theory calculations.

Standardisierter Computer-basiert-organisierter Report des EEG (SCORE) – Eine strukturierende Form der EEG-Befundung

Eine 2013 von der „International Federation of Clinical Neurophysiology“ gegründete Taskforce hat eine international konsensfähige EEG-Terminologie entwickelt. Im Folgenden soll das Resultat – die 2. Version des Standardized Computer-based Organized Reporting of EEG (SCORE) - vorgestellt werden. Die Terminologie wurde im Rahmen eines Softwarepaketes (SCORE-EEG) in der klinischen Praxis an über 12.000 EEGs getestet. Die Auswahl der Begriffe ist kontextabhängig: die initiale Auswahl bestimmt, welche weiteren Auswahlmöglichkeiten zur Verfügung stehen. Im Verlauf wird automatisch ein Befund erstellt und dessen Einzelmerkmale in eine Datenbank eingespeist. SCORE verfügt über Module spezifisch für die Befundung epileptischer Anfälle, sowie charakteristischer neonataler und intensivmedizinische EEG-Merkmale. SCORE ist nicht nur ein nützliches Werkzeug im ambulanten, klinischen und wissenschaftlichen Setting, es erleichtert auch Qualitätssicherung, Datenaustausch und die EEG-Aus und Weiterbildung.

High-frequency oscillations (HFOs) in clinical epilepsy

Epilepsy is one of the most frequent neurological diseases. In focal medically refractory epilepsies, successful surgical treatment largely depends on the identification of epileptogenic zone. High-frequency oscillations (HFOs) between 80 and 500Hz, which can be recorded with EEG, may be novel markers of the epileptogenic zone. This review discusses the clinical importance of HFOs as markers of epileptogenicity and their application in different types of epilepsies. HFOs are clearly linked to the seizure onset zone, and the surgical removal of regions generating them correlates with a seizure free post-surgical outcome. Moreover, HFOs reflect the seizure-generating capability of the underlying tissue, since they are more frequent after the reduction of antiepileptic drugs. They can be successfully used in pediatric epilepsies such as epileptic spasms and help to understand the generation of this specific type of seizures. While mostly recorded on intracranial EEGs, new studies suggest that identification of HFOs on scalp EEG or magnetoencephalography (MEG) is possible as well. Thus not only patients with refractory epilepsies and invasive recordings but all patients might profit from the analysis of HFOs. Despite these promising results, the analysis of HFOs is not a routine clinical procedure; most results are derived from relatively small cohorts of patients and many aspects are not yet fully understood. Thus the review concludes that even if HFOs are promising biomarkers of epileptic tissue, there are still uncertainties about mechanisms of generation, methods of analysis, and clinical applicability. Large multicenter prospective studies are needed prior to widespread clinical application.

Modeling temperature-mediated fluctuation in colony size in the fire ant, Solenopsis invicta

In the social insects, colony size is central to the survival of the queen. Two endogenous factors, worker longevity and queen's daily egg production, are known to determine maximum colony size. A third endogenous factor, duration of worker development from egg to adult, regulates the rate of colony growth. In this paper, we report findings from a simulation quantifying the effects of temperature on colony size in the fire ant, Solenopsis invicta. The monthly average temperature over a six year period for the panhandle of north Florida was interpolated to determine the effects of daily temperature on a queen's egg production, worker developmental time and worker longevity. Additional daily temperatures were simulated: 7°C higher and 7°C lower than daily temperatures for north Florida. As expected, colony size was the largest when annual temperatures were the highest across seasons, ranging from 57,000 to 187,000. Colony size at intermediate daily temperatures ranged from 14,000 to 103,000; small colonies recovered rapidly as temperatures warmed. Colony size at lower daily temperatures ranged from 14,000 to 21,000. Extended worker longevity at lower temperatures compensated for low egg production and longer developmental time. And vice versa, the queen's high rate of egg production and the shorter developmental time compensated for shorter worker longevity at high temperatures. Because the fire ant nest consists of a heat-collecting dome in which to incubate brood during cold weather, and deep chambers in which to cool workers during hot weather, colony size is likely to be higher and more stable than our simulation showed. The extended longevity of workers and queens at low temperatures, and perhaps their ability to hibernate below the permafrost, might explain the ability of ants to colonize habitats worldwide.

Electron density measurement of cesium seeded negative ion source by surface wave probe

Electron density measurements of a large-scaled negative ion source were carried out with a surface wave probe. By comparison of the electron densities determined with the surface wave probe and a Langmuir probe, it was confirmed that the surface wave probe is highly available for diagnostic of the electron density in H(-) ion sources. In addition, it was found that the ratio of the electron density to the H(-) ion density dramatically decreases with increase of a bias voltage and the H(-) ions become dominant negative particles at the bias voltage of more than 6 V.

Spatial distribution of the charged particles and potentials during beam extraction in a negative-ion source

We report on the characteristics of the electronegative plasma in a large-scale hydrogen negative ion (H(-)) source. The measurement has been made with a time-resolved Langmuir probe installed in the beam extraction region. The H(-) density is monitored with a cavity ring-down system to identify the electrons in the negative charges. The electron-saturation current decreases rapidly after starting to seed Cs, and ion-ion plasma is observed in the extraction region. The H(-) density steps down during the beam extraction and the electron density jumps up correspondingly. The time integral of the decreasing H(-) charge density agrees well with the electron charge collected with the probe. The agreement of the charges is interpreted to indicate that the H(-) density decreasing at the beam extraction is compensated by the electrons diffusing from the driver region. In the plasmas with very low electron density, the pre-sheath of the extraction field penetrates deeply inside the plasmas. That is because the shielding length in those plasmas is longer than that in the usual electron-ion plasmas, and furthermore the electrons are suppressed to diffuse to the extraction region due to the strong magnetic field.

Characteristics of 80 keV positive ion source for Large Helical Device

An additional beamline, BL5, equipped with four positive ion sources will be installed on Large Helical Device (LHD) in 2010. The performance of an ion source which generates 80 keV deuterium and 60 keV hydrogen beams was investigated. The structure of the ion source is based on that of a BL4 ion source on LHD. The main differences between the ion sources for the BL4 and BL5 are the acceleration voltages and the materials of plasma electrodes: copper and molybdenum, respectively. The molybdenum plasma electrode for BL5 has better performance than the copper plasma electrode of BL4. The integrated performance of the ion source for BL5 reached a value equivalent to approximately 58 A in the beam current of hydrogen positive ion at 60 keV in the beam energy.

Beamlet characteristics in the accelerator with multislot grounded grid

Characteristics of multibeamlets are investigated by means of beamlet monitoring technique. The beamlets are extracted from an accelerator with multislot grounded grid and the profiles are observed as infrared images of temperature distributions on a cold isostatic pressed graphite plate exposed by H-beamlets. The optimal horizontal and vertical divergence angles of single beamlet are estimated at 4.1 and 6.1 mrad, respectively.

Diffusion tensor imaging study of the cortical origin and course of the corticospinal tract in healthy children

BACKGROUND AND PURPOSE

Several studies have questioned the traditional belief that the corticospinal tract (CST) arises exclusively from the precentral gyrus and passes through the anterior half of the posterior limb of the internal capsule (PLIC) in humans; however, no direct evidence existed from structural imaging, and developmental aspects of CST origin have not been clarified. We used diffusion tensor imaging (DTI) tractography to test the hypotheses that CST can originate from both pre- and postcentral gyri and is located posteriorly in the PLIC, and we also determined how age, sex, or handedness affected these locations.

MATERIALS AND METHODS

Forty-two healthy children (2.6-17.5 years of age; 20 girls) underwent DTI. Subsequently, tractography was performed on the basis of fiber assignment by continuous tracking (FACT) algorithm and brute force approach, with a fractional anisotropy (FA) threshold of <0.2 and an angle threshold of >50 degrees . The CST was isolated by using a knowledge-based region-of-interest approach, and its cortical origin and location on the PLIC was determined.

RESULTS

DTI revealed that the CST originated from both pre- and postcentral gyri in 71.4% of hemispheres, from the precentral gyrus only in 19%, and from the postcentral gyrus only in 7.1%. The overall distribution was similar in both hemispheres. However, children with CST originating from both pre- and postcentral gyri were older (mean, 11.1 years of age) than those with precentral origin (mean, 5.8 years of age) or postcentral origin (mean, 7.8 years of age) only (P = .00003). The center of the CST was localized at 65% of the length (from its anterior margin) of the PLIC, and the CST occupied 26.5% of its anteroposterior length. There was a significant positive correlation between age and FA of the CST (r = 0.49; P = .002). The volume of the precentral portion of the left CST was significantly higher than that of its postcentral portion (P = .01) and that of the right CST (P = .0002). The pattern of cortical origin of CST, its location at the level of PLIC, and its volume and FA were unaffected by sex or handedness.

CONCLUSIONS

The CST most frequently originates from both pre- and postcentral gyri, especially in older children, and is typically centered approximately two thirds of the distance from the anterior margin of the PLIC and occupies about a quarter of its anteroposterior length. In young children, the CST can often be seen originating exclusively from the precentral gyrus by DTI.

Optimal control of vaccine distribution in a rabies metapopulation model

We consider an SIR metapopulation model for the spread of rabies in raccoons. This system of ordinary differential equations considers subpopulations connected by movement. Vaccine for raccoons is distributed through food baits. We apply optimal control theory to find the best timing for distribution of vaccine in each of the linked subpopulations across the landscape. This strategy is chosen to limit the disease optimally by making the number of infections as small as possible while accounting for the cost of vaccination.

Neutral beam injection with an improved accelerator for LHD

The beam profiles, port-through, rates and injection powers obtained with an improved accelerator with the multislot grounded grid are described. The accelerator has a combination of a steering grid with racetrack shaped aperture and multislot grounded grid to improve the beam optics. The optimal beam optics is obtained at the voltage ratio of 16.5-16.8, and the profiles are well fit by superposing multibeamlets with the divergent angles of 5.0 and 7.2 mrad along the direction parallel to the long and short axes of the slots of grounded grid. By adopting the racetrack shaped steering grid, the port-through rate increases from 34% to 38%, and the maximum injection power reaches 6 MW/187 keV.

Spectroscopic observations of beam and source plasma light and testing Cs-deposition monitor in the large area negative ion source for LHD-NBI

In the large area negative ion source for the LHD negative-ion-(H(-))-based neutral beam system, (I) we used the spectrometer to measure caesium lines in the source plasma during beam shots. (II) With Doppler-shifted measurements, the H(alpha) line at three different locations along the beam as well as the spectrum profile for cases of different plasma grid areas. (III) Caesium deposition monitor with a high speed shutter was tested to measure the weight of the deposited Cs layer. In the observation, cleaner spectra of Doppler-shifted H(alpha) line with only a small level of background light were obtained at a new observation port which viewed the blueshifted light in the drift region after the accelerator of a LHD ion source. Both the amounts of Cs I (852 nm, neutral Cs(0)) and Cs II (522 nm, Cs(+)) in the source plasma light rose sharply when beam acceleration began, and continued rising during a 10 s pulse. It was thought that this was because the cesium was evaporated/sputtered from the source back plate by the back-streaming positive ions. Cs deposition rate to the crystal sensor measured by adjusting the shutter open time was evaluated to be 2.9 nanograms/s cm(2) for preliminary testing. More neutral Cs tended to be evolved in the source after arc discharge. Much Cs could be consumed in a high rate-pulsed operation (such as LHD source).

Chaos analysis of electro encephalography and control of seizure attack of epilepsy patients

In order to evaluate the EEG of patients with epilepsy, chaos analysis was performed for the subdural EEG time series data. The chaos attractor was reconstructed in the phase space and the correlation dimension. KS entropy calculated from the Lyapunov exponents was evaluated. Before the seizure attack, the KS entropy showed a lower value when compared with the time series data recorded during healthy condition. The results of our study suggest that it is possible to predict the seizure attack by the chaos analysis of the EEG signal. Further, we aim at developing an automatic control system for predicting a seizure attack by the use of local cooling of the focus with Peltier elements.

Symmetries in BF and HAADF STEM image calculations

Reductions in bright-field (BF) scanning transmission electron microscopy (STEM) and high-angle annular dark-field (HAADF) STEM image calculations with the aid of Bloch wave symmetry are discussed under assumptions that an absorption potential is written by a local potential and a zero-order Laue zone lies parallel to the crystal surface. Translational symmetry allows us to take only partial incident beams in the first Brillouin zone instead of enormous number of partial incident beams in a large convergent disk. Two dimensional point group confines partial incident beams to an irreducible area in addition to factoring a dispersion matrix into noninteracting submatrices on a high symmetry line using the projection operator. The drastic reductions in computing time and memory enable us to readily calculate various BF STEM and HAADF STEM images. The validity and accuracy are demonstrated in comparisons with high resolution experimental BF STEM and HAADF STEM images.

Lattice imaging in low-angle and high-angle bright-field scanning transmission electron microscopy

Atomic resolution low-angle bright-field (LABF) scanning transmission electron-microscope (STEM) images and high-angle bright-field (HABF) STEM images of [011]-orientated Si have been experimentally obtained together with high-angle annular dark-field (HAADF) STEM images. The contrast formation mechanisms of the LABF STEM and HABF STEM images are examined in comparison with HAADF STEM images. The HABF STEM images independent of defocus and thickness have spatial resolution comparable with HAADF STEM images, and are shown to be given as a simple convolution under the non-dispersion approximation of localized Bloch waves.

Rasmussen encephalitis associated with Parry-Romberg syndrome

Parry-Romberg syndrome is a rare disorder associated with unilateral facial atrophy involving skin, subcutaneous tissue, skeletal muscle, and bone. Occasionally, there is CNS involvement with epilepsy being the most common CNS manifestation. The authors report a child with Parry-Romberg syndrome with a course strongly suggestive of Rasmussen encephalitis. The boy underwent hemispherectomy, and pathology showed the typical findings of Rasmussen encephalitis, suggesting that these two conditions may share common etiologic factors.

Alpha-methyl-L-tryptophan PET detects epileptogenic cortex in children with intractable epilepsy

BACKGROUND

In children with tuberous sclerosis, the PET tracer alpha[11C]methyl-L-tryptophan (AMT) has been shown to be selectively taken up by epileptogenic tubers, thus allowing differentiation from nonepileptogenic tubers in the interictal state.

OBJECTIVE

To determine whether cortical areas showing increased AMT uptake in children without tuberous sclerosis complex with intractable neocortical epilepsy indicate the epileptogenic zone, and to assess the relative contributions of AMT and 2-deoxy-2[18F]fluoro-D-glucose (FDG) PET abnormalities to the localization of epileptogenic cortical regions.

METHODS

Areas of increased AMT and decreased FDG uptake were marked objectively as regions with abnormal asymmetry using an in-house written software in 27 children who underwent comprehensive evaluation for resective epilepsy surgery. The marked PET abnormalities were compared to the locations of scalp and subdural EEG epileptiform abnormalities, as well as histology and surgical outcome.

RESULTS

Focal cortical increases of AMT uptake were found in 15 patients. The lobar sensitivity (39.0%) of AMT PET for seizure onset was lower, but its specificity (100%) was higher (p < 0.0001) than that of hypometabolism on FDG PET (sensitivity 73.2%, specificity 62.7%). AMT PET abnormalities were smaller than corresponding FDG PET hypometabolic regions (p = 0.002), and increased AMT uptake occurred in two patients with nonlocalizing FDG PET. Histologically verified cortical developmental malformations were associated with increased AMT uptake (p = 0.044). Subdural electrodes adjacent to the area of increased AMT uptake were most often involved in seizure onset.

CONCLUSIONS

Focal increase of cortical AMT uptake in children is less sensitive but more specific for the lobe of seizure onset than corresponding FDG PET hypometabolism, and it is often associated with epileptogenic cortical developmental malformations. AMT PET can assist placement of subdural electrodes even when MRI and FDG PET fail to provide adequate localizing information. Cortical areas adjacent to increased AMT uptake should be carefully addressed by intracranial EEG because these regions often show a high degree of epileptogenicity.

Surgical treatment of West syndrome

The discovery of focal or multifocal cortical lesions using magnetic resonance imaging (MRI) and positron emission tomography (PET) scanning in the majority of infants with West syndrome has led to a surgical approach in the treatment of some patients with intractable infantile spasms. The locations of these lesions should be concordant with localization of focal ictal and/or interictal electroencephalographic (EEG) abnormalities prior to proceeding with cortical resection. When a single lesion is present on the MRI or PET, and there is good correlation with EEG localization, surgical treatment is generally quite favorable in terms of both seizure control and cognitive development. Interictal glucose metabolism PET scans in children with intractable cryptogenic infantile spasms show unifocal cortical hypometabolism in about 20% of cases. In the majority, however, multifocal asymmetric hypometabolism is suggestive of multifocal underlying lesions, possibly multifocal cortical dysplasia. When the pattern of glucose hypometabolism is symmetric, a lesional etiology is less likely, thus neurometabolic or neurogenetic disorders should be considered. Therefore, the pattern of glucose hypometabolism on PET in infants with intractable cryptogenic spasms is a useful guide to decide whether a medical or surgical approach should be undertaken. In order to achieve the best cognitive outcome with surgery, it is important to resect the entire 'nociferous' area rather than just the seizure focus. Our research with new PET imaging probes has attempted to provide a comprehensive evaluation of the epileptogenic zone including the 'nociferous' cortex. We have used [(11)C]flumazenil (FMZ), which labels gamma aminobutyric acid(A) (GABA(A)) receptors, and have found this to be particularly useful in showing: (i) decreased receptor binding with medial temporal involvement thus indicating resection of medial temporal structures, (ii) the peri-lesional epileptogenic zone surrounding MRI lesions, (iii) the seizure onset zone in MRI-negative cases, and (iv) potential secondary epileptic foci. Another recently developed PET probe, alpha[(11)C]methyl-L-tryptophan (AMT) which is a precursor for the serotonin and the kynurenine metabolism pathways, is capable of differentiating between epileptogenic and non-epileptogenic tubers in patients with tuberous sclerosis complex and intractable epilepsy (including infantile spasms). Subsequently, we have applied AMT PET in patients with multifocal cortical dysplasia to determine the predominant seizure focus, and the results have been promising with regard to seizure control but not cognitive development. Thus, the introduction of newer more specific PET probes for epilepsy has led to improved and more accurate localization of seizure foci that should ultimately improve outcome of epilepsy surgery in West syndrome.

Autism in tuberous sclerosis complex is related to both cortical and subcortical dysfunction

OBJECTIVE

To examine the relationship between autism and epilepsy in relation to structural and functional brain abnormalities in children with tuberous sclerosis complex (TSC).

METHODS

Children with TSC and intractable epilepsy underwent MRI as well as PET scans with 2-deoxy-2-[(18)F]fluoro-D-glucose (FDG) and alpha-[(11)C]methyl-L-tryptophan (AMT). Based on the results of Autism Diagnostic Interview-Revised, Gilliam Autism Rating Scale, and overall adaptive behavioral composite (OABC) from Vineland Adaptive Behavior Scale, subjects were divided into three groups: autistic (OABC < 70; n = 9), mentally-retarded nonautistic (OABC < 70; n = 9), and relatively normal intelligence (OABC > or = 70; n = 8).

RESULTS

PET studies showed that the autistic group had decreased glucose metabolism in the lateral temporal gyri bilaterally, increased glucose metabolism in the deep cerebellar nuclei bilaterally, and increased AMT uptake in the caudate nuclei bilaterally, compared to the mentally-retarded nonautistic group. In addition, a history of infantile spasms and glucose hypometabolism in the lateral temporal gyri were both significantly associated with communication disturbance. Glucose hypermetabolism in the deep cerebellar nuclei and increased AMT uptake in the caudate nuclei were both related to stereotypical behaviors and impaired social interaction, as well as communication disturbance.

CONCLUSIONS

These results suggest that generalized epilepsy in early life and functional deficits in the temporal neocortices may be associated with communication delays, and that functional imbalance in subcortical circuits may be associated with stereotypical behaviors and impaired social interaction in children with TSC.

Sturge-Weber syndrome: correlation between clinical course and FDG PET findings

OBJECTIVE

To determine whether the extent and degree of glucose hypometabolism defined by PET correlate with seizure characteristics, cognitive function, and interictal EEG abnormalities in children with unilateral cerebral involvement of Sturge-Weber syndrome (SWS).

METHODS

2-Deoxy-2[18F]fluoro-D-glucose (FDG) PET was performed in 13 children (age range 0.7 to 15.1 years; five boys, eight girls) with unilateral SWS. Based on asymmetries between homologous cortical areas in FDG PET images, cortical areas of mildly (10% to 20% decrease), and severely (>20% decrease) asymmetric cortical metabolism were defined. These areas were normalized to the size of the ipsilateral hemisphere and correlated with clinical seizure characteristics, full-scale IQ, and interictal EEG abnormalities.

RESULTS

Both seizure frequency (p = 0.027) and lifetime number of seizures (p = 0.017) showed a positive correlation with the area (expressed as the percentage of cortical area of ipsilateral hemisphere) of mildly asymmetric cortical metabolism. Patients with higher IQ had a shorter duration of epilepsy (p = 0.044) and a larger area of severely asymmetric cortical metabolism (p = 0.044). Patients with bilateral interictal EEG abnormalities had larger lifetime number of seizures (p = 0.042), lower IQ (p = 0.024), and smaller area of severely asymmetric cortical metabolism (p = 0.019) than those with only ipsilateral EEG abnormalities.

CONCLUSIONS

Association of severely asymmetric cortical metabolism with relatively preserved cognitive function in SWS suggests that functional reorganization occurs more readily when cortex is severely rather than mildly damaged. Therefore, the area of mildly asymmetric cortical metabolism may exert a nociferous effect on the remaining of the brain. Thus, the extent and degree of glucose asymmetry detected by PET are sensitive markers of seizure severity and cognitive decline in SWS.

A study of novel polymorphisms in the upstream region of vasoactive intestinal peptide receptor type 2 gene in autism

We investigated the vasoactive intestinal peptide receptor type 2 (VIPR2) gene as a candidate gene for autism. We searched for mutations in the VIPR2 gene in autistic individuals, and 10 novel polymorphisms were identified. Three polymorphisms in the upstream region were studied in detail, and there was no significant difference in the frequencies between the autistic group (n = 14) and unrelated controls (n = 52). The distribution of the genotypes in two of the three polymorphisms differed somewhat between autistic subjects with gastrointestinal problems and those without. Moreover, there was a trend showing a correlation between the genotypes for the third polymorphism and the severity of stereotypical behavior as ranked by the Gilliam Autism Rating Scale. These preliminary results suggest that VIPR2 may have a role in gastrointestinal symptoms and stereotypical behaviors in autism, although a larger collection of samples suitable for transmission disequilibrium tests is necessary to validate the results.

Multimodality imaging for improved detection of epileptogenic foci in tuberous sclerosis complex

OBJECTIVE

Using interictal alpha-[11C]methyl-l-tryptophan ([11C]AMT) PET scan, the authors have undertaken a quantitative analysis of all tubers visible on MRI or 2-deoxy-2-[18F]fluoro-d-glucose ([18F]FDG) PET, to determine the relationship between [11C]AMT uptake and epileptic activity on EEG.

BACKGROUND

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder, often associated with cortical tubers and intractable epilepsy. The authors have shown previously that [11C]AMT PET scans show high tracer uptake in some epileptogenic tubers and low uptake in the remaining tubers.

METHODS

Eighteen children, age 7 months to 16 years, were studied. Patients underwent video-EEG monitoring, PET scans of [11C]AMT and [18F]FDG, and T2-weighted or fluid-attenuated inversion recovery (FLAIR) MRI. [11C]AMT uptake values were measured in 258 cortical tubers delineated with coregistered MRI or [18F]FDG scans. Uptake ratios were calculated between the [11C]AMT uptake in tubers and those for normal cortex (tuber/normal cortex). Using the region of epileptiform activity, the authors performed receiver operator characteristics (ROC) analysis and determined the optimal uptake ratio for detecting presumed epileptogenic tubers.

RESULTS

Tuber uptake ratios ranged from 0.6 to 2.0. Tuber uptake ratios in the epileptic lobes were higher than those in the nonepileptic lobes (p < 0.0001). All 15 patients with focal seizure activity showed one or more lesions with uptake ratio above 0.98 in the epileptic lobe. ROC analysis showed that a tuber uptake ratio of 0.98 resulted in a specificity of 0.91.

CONCLUSIONS

Cortical tubers with [11C]AMT uptake greater than or equal to normal cortex are significantly related to epileptiform activity in that lobe. Together, interictal [11C]AMT PET and FLAIR MRI improve the detection of potentially epileptogenic tubers in patients with TSC being evaluated for epilepsy surgery.

[Pathological features of dysembryoplastic neuroepithelial tumor (DNT): study of five surgical cases with intractable epilepsies]

The dysembryoplastic neuroepithelial tumor (DNT), characterized by its favorable prognosis, must be precisely differentiated from other gliomas to prevent overtreatment by radio/chemotherapy. We studied, here, pathological features of five surgical cases of DNT with intractable epilepsies. There were two males and three females with a median age of 20.4 years (range 12-41). We evaluated lesional topography, gross appearances and microscopic findings including immunohistochemical data. One tumor was located in the temporal lobe, another two in the parietal lobe, another in the occipital lobe, and the other one in the occipito-parietal junction. The lesions were predominantly intracortical in all cases. Macroscopically, two tumors were grayish-soft, another two were yellowish-elastic, and the other one was resected as soft-mucinous fragments. Microscopically, the main glial components were oligodendrocyte-like cells (OLCs) in all cases, except for one case in which atypical glial cells were also prominent. Histopathological characteristics of the DNTs included the specific glioneuronal elements (the mixture of OLCs and neurons) in four cases, alveolar pattern (all cases), microcystic degeneration (all cases), multinodular architecture (four cases), and adjacent cortical dysplasia (all cases). Immunohistochemically, Ki-67 labelling indices ranged from 0 to 0.8%. OLCs were positive for glial fibrillary acidic protein in two cases, for S-100 protein in all cases, for synaptophysin in two cases, and for class III beta tubulin in all cases. Pathological features of our cases were characterized by its heterogeneous histological appearances and divergent cellular differentiation.

Surgical treatment of intractable epilepsy originating from the primary sensory area of the hand--case report

A 14-year-old right-handed girl presented with intractable epilepsy originating from the primary sensory area of the hand, manifesting as sensory partial seizures in the left hand with secondary generalization. Neurological examination showed no abnormal findings. Magnetic resonance imaging, magnetoencephalography, and cortical stimulation using chronic subdural electrodes demonstrated a lesion located in the primary sensory cortex of the hand, in which the ictal onset zone was identified by 24-hour intracranial electroencephalographic recording. Surgical resection of the lesion and multiple subpial transections of the adjacent cortices were performed. The histological diagnosis was dysembryoplastic neuroepithelial tumor (DNT). She was completely free of seizures without permanent sensory deficits postoperatively. DNT located in the primary sensory hand area may be resectable without causing postoperative sensory deficits, if accurate functional mapping and surgical resection are performed.

A Dynamic Type of Vernier Acuity in the Visual Prediction of Motion Trajectory

The purpose of the experiment was to analyse a dynamic type of Vernier acuity in the visual prediction of the trajectory of linear apparent motion. The subjects were shown a single moving dot, which moved from the left end to the right end of a CRT. The change in dot position between two successive frames was 0.15 deg. Midway through the trajectory the dot moved behind an amodal occluding square, thus being invisible in this area. The vertical position where the dot re-emerged from behind the occluding square was varied, with 14 conditions for deviations both above and below the ‘correct’ locus of straight movement. A unit step of the deviation was 0.029 deg. There were three SOA conditions (13 ms, 21 ms, and 26 ms). In a 2AFC paradigm, the subjects had to report on which of two presentations the dot reappeared in the ‘correct’ position.

We applied Probit analysis to fit a cumulative normal distribution to the result of each SOA condition and each deviation direction. We defined a value giving 75% correct response as a threshold value. Within each SOA condition, there was no difference between the threshold for deviations above or below the correct position, nor did threshold values between three SOA conditions show significant differences (ANOVA). We compare and discuss Vernier-acuity thresholds with and without amodal occlusion of the locus.

Hepatic arterial infusion chemotherapy combined with hyperthermia for metastatic liver tumors of colorectal cancer

The efficacy of combined hepatic arterial infusion chemotherapy and hyperthermia for unresectable hepatic tumors of colorectal cancer was retrospectively compared with hepatic arterial infusion chemotherapy alone. Nine cases were treated with combination therapy and eight cases were treated with hepatic arterial infusion alone. The response rate in the combined hepatic arterial infusion/hyperthermia group was higher (44% v 25%) and the survival period longer (2-year survival, 35% v 12%) than in the group treated with hepatic arterial infusion alone. The toxicity was not severe, with the exception of gastrointestinal symptoms, suggesting that this combination of modalities is useful in the treatment of metastatic liver tumors.

[Clinical experience with an ampicillin suppository (KS-R1) in pediatrics]

Ampicillin suppository (KS-R1) was given to 16 children with the following acute bacterial infection; 4 cases of acute pharyngitis, 2 cases of acute tonsillitis, 5 cases of acute bronchitis, 4 cases of bronchopneumonia, 1 case of group A beta-streptococcal infection. Out of 16 patients, good clinical responses were obtained in 16 patients, and bacteriological effectiveness was seen in all 3 cases. Side effects with KS-R1 were observed in 4 cases: 3 cases were perianal redness, and 4 cases were soft stool. From the above clinical results, KS-R1 is useful antibiotic suppository for treating the pediatric patients with various kinds of bacterial infections.

[Clinical experience with T-1982 (cefbuperazone) in the pediatric field]

T-1982 (cefbuperazone) was given intravenously to 21 children with the following acute bacterial infections; 13 cases of bronchopneumonia, 2 cases of urinary tract infection, 1 case of subcutaneous abscess, 1 case of cervical purulent lymphadenitis and acute tonsillitis, and 4 cases of acute bronchitis. Clinical effectiveness was obtained in 20 cases out of 21 cases and bacteriological effectiveness in 7 cases out of 8 cases. As for the side effects, 1 patient had asymptomatic eosinophilia, but no other laboratory abnormalities were observed. Above results suggest that T-1982 is a useful antibiotic for treating pediatric patients with various kinds of bacterial infections.

Calcified gastric leiomyoma--a case report

A 62 year-old man was admitted with the chief complaint of a epigastric pain and difficulty of swallowing. Examination of the upper gastrointestinal tract revealed a calcified mass causing a smooth filling defect at the lesser curvature of the cardia. At laparotomy, a localized tumor was detected beneath the serosa of the stomach. The excised tumor was 4 x 4 x 1.6 cm and the pathological diagnosis was calcified leiomyoma probably due to cytoplasmic degeneration. In this paper, details of the case are described and the related literature is reviewed.

Blue rubber bleb nevus syndrome: report of a case

A 21-year-old man had blue rubber bleb nevus syndrome: 1) hemangiomas of the skin all over the body; 2) hemangiomas of the digestive system; 3) iron-deficiency anemia. A giant mass of hemangiomas in the tranverse colon was resected surgically.