Epileptic High-frequency Oscillations in Scalp Electroencephalography

Electroencephalography (EEG) examines the functional state of the brain. High-frequency oscillations (HFOs) in the ripple (80-200/250 Hz) and fast ripple (200/250-500/600 Hz) bands have recently been attracting attention, and their recording has been enabled by advancements in digital EEG techniques. The detection of HFOs was previously limited to intracranial EEG, but fast oscillations (FOs) in the gamma (40-80 Hz) and ripple bands can now be detected over the scalp. HFOs and FOs have been shown to be related to epileptogenicity in intracranial EEG and scalp EEG, respectively. A large number of FOs are found in the scalp EEGs of pediatric patients with various epileptic encephalopathies, particularly West syndrome. FOs are suggested to be a biomarker of the epileptogenic cortical region in epilepsy surgery. FOs are detectable even in patients with idiopathic focal epilepsies, including benign epilepsy with centrotemporal spikes and Panayiotopoulos syndrome, who are not generally candidates for operation. The detection of HFOs and FOs may provide clues to the pathophysiology of epilepsy and the relationship between HFOs and cognitive dysfunction

An Optimal Investment Policy to Control the Land-based Water Pollutant into the Sea of Japan

Northeast Asia countries (e.g. around the Sea of Japan area) cooperate in economic and environmental policies, etc., because the comprehensive problems like the climate change and global warming occur in recent years. The ring Sea of Japan area consists of Japan, Republic of Korea, China, and Far East Russia in Northeast Asia, and the countries have to join forces in order to control the ocean environment and attain the sustainable development in the region. In this study, we try to evaluate the policy measure to control the land-based water pollutant into the Sea of Japan through a system simulation approach. The system simulation model is formulated a definition of an objective function and the structure of water pollutants inflow and the socio-economic system of the target countries and regions of the ring Sea of Japan. We present an optimal international policy for environmental investment taking account of economic situations and environmental influences of this area over a certain period of time through the dynamic simulation.

Dravet Syndrome : A Genetic Epileptic Disorder

Dravet syndrome (DS), or severe myoclonic epilepsy in infancy, is one of the most severe types of genetic epilepsy. It is characterized by the initial occurrence of febrile or afebrile seizures that often evolve into status epilepticus in infants with normal development, and by the subsequent appearance of myoclonic and/or atypical absence seizures as well as complex partial seizures. The key feature that characterizes DS is fever sensitivity, although photosensitivity and pattern-sensitivity are also often seen. The prognosis is unfavorable in most cases. Seizures become drug-resistant and persist, with many patients suffering from motor and cognitive impairment. Mutations of SCN1A, which encodes the voltage-gated sodium channel NaV1.1, are the most frequent genetic cause of this syndrome. SCN1A mutations and/or microchromosomal rearrangements involving SCN1A are detected in about 85% of patients. Mutations of PCDH19 have also been reported in female patients with clinical findings compatible with DS. PCDH19 mutations might account for 5% of overall DS cases. Thirty years after its first description, DS is considered as a model of channelopathy. This survey reviews recent developments in the research literature on DS, focusing on the clinical course, as well as its genetic causes