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Norichika Iwashiro,1 Yosuke Takano,1 Tatsunobu Natsubori,1 Yuta Aoki,1 Noriaki Yahata,1,2 Wataru Gonoi,3 Akira Kunimatsu,3 Osamu Abe,3 Kiyoto Kasai,1 Hidenori Yamasue4 1Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan; 2Department of Molecular Imaging and Theranostics, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba-city, Chiba, Japan; 3Department of Radiology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Japan; 4Department of Psychiatry, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu City, Japan Background and purpose: Previous research has suggested that deficits in emotion recognition are involved in the pathogenesis of persecutory delusion in schizophrenia. Although disruption in auditory and language processing is crucial in the pathophysiology of schizophrenia, the neural basis for the deficits in emotion recognition of auditorily presented language stimuli and its relation to persecutory delusion have not yet been clarified. Patients and methods: The current functional magnetic resonance imaging study used a dichotic listening task for 15 patients with schizophrenia and 23 healthy controls matched for age, sex, parental socioeconomic background, handedness, dexterous ear, and intelligence quotient. The participants completed a word recognition task on the attended side in which a word with emotionally valenced content (negative/neutral) was presented to one ear and a different neutral word was presented to the other ear. Participants selectively attended to either ear. Results: The whole brain analysis detected the aberrant neural activity in the right inferior frontal gyrus in the patients with schizophrenia compared to that in the controls (P

Shingo Kakeda,1 Keita Watanabe,1 Asuka Katsuki,2 Koichiro Sugimoto,1 Issei Ueda,1 Natsuki Igata,1 Taro Kishi,3 Nakao Iwata,3 Osamu Abe,4 Reiji Yoshimura,2 Yukunori Korogi1 1Department of Radiology, University of Occupational and Environmental Health, Kitakyushu, Japan; 2Department of Psychiatry, University of Occupational and Environmental Health, Kitakyushu, Japan; 3Department of Psychiatry, Fujita Health University, School of Medicine, Toyoake, Japan; 4Department of Radiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan Background: A genome-wide association study using megadata identified 17 single-nucleotide polymorphisms (SNPs) in candidate genes for major depressive disorder (MDD). These MDD susceptibility polymorphisms may affect white matter (WM) integrity. This study aimed to investigate the relationship between WM alterations and 17 SNPs in candidate genes for MDD in the first depressive episode of drug-naive MDD patients using a tract-based spatial statistics (TBSS) method. Methods: Thirty-five drug-naive MDD patients with a first depressive episode and 47 age- and sex-matched healthy subjects underwent diffusion tensor imaging scans and genotyping. The genotype–diagnosis interactions related to WM integrity were evaluated using TBSS for the 17 SNPs. Results: For the anterior thalamic radiation, cingulum, corticospinal tract, inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, superior longitudinal fasciculus, uncinate fasciculus, forceps major, and forceps minor, the genotype effect significantly differed between diagnosis groups (P

Joji Nishimura,1 Shingo Kakeda,1 Osamu Abe,2 Reiji Yoshimura,3 Keita Watanabe,1 Naoki Goto,3 Hikaru Hori,3 Toru Sato,1 Hidemasa Takao,4 Hiroyuki Kabasawa,5 Jun Nakamura,3 Yukunori Korogi1 1Department of Radiology, University of Occupational and Environmental Health School of Medicine, Fukuoka, Japan; 2Department of Radiology, Graduate School of Medicine, Nihon University, Tokyo, Japan; 3Department of Psychiatry, University of Occupational and Environmental Health School of Medicine, Fukuoka, Japan; 4Department of Radiology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan; 5MR Applied Science Laboratory Japan, GE Yokogawa Medical Systems, Hino-shi, Tokyo, Japan Abstract: The aims of this study are to determine how the interval changes of the brain structures in the early stage of first-episode schizophrenia relate to the interval changes in the clinical data, including the clinical symptoms of schizophrenia and catecholaminergic measures (plasma homovanillic acid [HVA] and 3-methoxy-4-hydroxyphenylglycol [MHPG]). Regional brain volumes and fractional anisotropy (FA)/mean diffusivity (MD) with diffusion tensor imaging (DTI) were measured at baseline and 6-month follow-up in a 3T magnetic resonance imaging (MRI) system in a cohort of 16 schizophrenic patients, who were in their first episode at the time of baseline MRI. At the time of baseline and follow-up MRI, all 16 patients underwent evaluations that included a psychopathological assessment (Positive and Negative Syndrome Scale [PANSS]) and peripheral catecholaminergic measures (plasma MHPG or HVA). For interval changes between baseline and follow-up MRI data (morphological change, MD, and FA), the correlation/regression analysis was performed as a series of single regression correlations in Statistical Parametric Mapping 5, with the interval changes in PANSS or plasma HVA and MHPG as the covariates of interest. Positive and inverse correlations contrasts were created, and in this preliminary analysis, a family-wise error-corrected threshold of P

Kenji Hayashi,1 Reiji Yoshimura,1 Shingo Kakeda,2 Taro Kishi,3 Osamu Abe,4 Wakako Umene-Nakano,1 Asuka Katsuki,1 Hikaru Hori,1 Atsuko Ikenouchi-Sugita,1 Keita Watanabe,2 Satoru Ide,2 Issei Ueda,2 Junji Moriya,2 Nakao Iwata,3 Yukunori Korogi,2 Marek Kubicki,5 Jun Nakamura1 1Department of Psychiatry, 2Department of Radiology, University of Occupational and Environmental Health, Kitakyushu, Japan; 3Department of Psychiatry, Fujita Health University, Toyoake, Japan; 4Department of Radiology, Nihon University School of Medicine, Tokyo, Japan; 5Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA Abstract: We investigated the association between the Val158Met polymorphism of the catechol-O-methyltransferase (COMT) gene, the Val66Met polymorphism of the brain-derived neurotrophic factor (BDNF) gene, and white matter changes in patients with major depressive disorder (MDD) and healthy subjects using diffusion tensor imaging (DTI). We studied 30 patients with MDD (17 males and 13 females, with mean age ± standard deviation [SD] =44±12 years) and 30 sex- and age-matched healthy controls (17 males and 13 females, aged 44±13 years). Using DTI analysis with a tract-based spatial statistics (TBSS) approach, we investigated the differences in fractional anisotropy, radial diffusivity, and axial diffusivity distribution among the three groups (patients with the COMT gene Val158Met, those with the BDNF gene Val66Met, and the healthy subjects). In a voxel-wise-based group comparison, we found significant decreases in fractional anisotropy and axial diffusivity within the temporal lobe white matter in the Met-carriers with MDD compared with the controls (P

We studied diurnal and daily variations in triple oxygen isotopes in the euphoric zone of the Sagami Bay during summer 2003 and 2004. There were sharp changes in physical processes, driven by changes in wind speeds, during the study period. Mixed-layer 17A anomalies were negatively correlated with wind speeds, whereas dissolved oxygen (DO) and chlorophyll a (Chl a) were positively correlated, suggesting that both physical and biological processes influence the [sup.17][DELTA] anomaly. Vertical mixing affected estimation of gross oxygen production (GOP) in the mixed layer, whereas horizontal advection was negligible in the Sagami Bay during the study period. Hourly GOP estimates are consistent with fast repetition rate fluorometer (FRRF) measurements' relatively higher estimates from the former method were due to the storing of past productivity signal. Daily integrated production estimated from [sup.17][DELTA] anomaly and FRRF were consistent during the entire study period, whereas the estimation from a [sup.18]O spike incubation technique showed good agreement with the other two techniques only when the water mass structure was unchanged in the mixed layer.

We studied daily, diurnal, and seasonal variations in triple oxygen isotopes in the Sagami Bay from May to October 2002. The variations in composition of triple oxygen isotopes are in association with changes in concentrations of dissolved oxygen (DO) and chlorophyll a (Chl a). The lowest [sup.17][DELTA] anomaly (excess [sup.17]O) was found during October and the highest in August. There was a prominent subsurface [sup.17][DELTA] anomaly maximum during June and August because of photosynthesis below the mixed layer and reduced gas exchange. The [sup.17][DELTA] anomaly was positively correlated with DO and Chl a, but with large scatter. The gross oxygen production (GOP) computed on the basis of triple oxygen isotopes is almost double the value given by the standard oxygen incubation method. This could possibly be because of inability to measure [O.sub.2] uptake rates in the light bottle and the consequent assumption that respiration is the same in light and dark bottles. GOP measured by a fast repetition rate fluorometer showed large daily variability, whereas GOP given by the [sup.17][DELTA] anomaly is within daily variability. This suggests that the [sup.17][DELTA] anomaly method measures average GOP over the residence time of DO in the mixed layer.

A chromatographic system was developed to separate oxygen from nitrogen, argon, carbon dioxide, and water vapor mixture for the determination of precise isotopic ratio measurements of oxygen in dissolved air. This system separates oxygen not only quantitatively but also rapidly as well; typical oxygen separation takes about 30 min. Fractionation of oxygen between liquid and gas phase was found to be similar to that of earlier reports.