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Neonatal hypoxic-ischemic encephalopathy (nHIE) is a major neonatal brain injury. Despite therapeutic hypothermia, mortality and sequelae remain severe. The lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is associated with the pathophysiology of nHIE. In this study, morphologic change and microglial activation under the nHIE condition and LOX-1 treatment were investigated. The microglial activity and proliferation were assessed with a novel morphologic method, immunostaining, and quantitative PCR in the rat brains of both nHIE model and anti–LOX-1 treatment. Circumference ratio, the long diameter ratio, the cell area ratio, and the roundness of microglia were calculated. The correlation of the morphologic metrics and microglial activation in nHIE model and anti–LOX-1 treated brains was evaluated. LOX-1 was expressed in activated ameboid and round microglia in the nHIE model rat brain. In the evaluation of microglial activation, the novel morphologic metrics correlated with all scales of the nHIE-damaged and treated brains. While the circumference and long diameter ratios had a positive correlation, the cell area ratio and roundness had a negative correlation. Anti–LOX-1 treatment attenuated morphologic microglial activation and proliferation, and suppressed the subsequent production of inflammatory mediators by microglia. In human nHIE, round microglia and endothelial cells expressed LOX-1. The results indicate that LOX-1 regulates microglial activation in nHIE and anti–LOX-1 treatment attenuates brain injury by suppressing microglial activation.

To clarify the relationship between structural and functional changes in the brains of patients with Rett syndrome (RTT) using multimodal magnetic resonance imaging (MRI).Nine subjects with typical RTT (RTTs) and an equal number of healthy controls (HCs) underwent structural MRI, diffusion tensor imaging (DTI), and resting-state functional MRI (rs-fMRI). The measurements obtained from each modality were statistically compared between RTTs and HCs and examined for their correlation with the clinical severity of RTTs.Structural MRI imaging revealed volume reductions in most cortical and subcortical regions of the brain. Remarkable volume reductions were observed in the frontal and parietal lobes, cerebellum, and subcortical regions including the putamen, hippocampus, and corpus callosum. DTI analysis revealed decreased white matter integrity in broad regions of the brain. Fractional anisotropy values were greatly decreased in the superior longitudinal fasciculus, corpus callosum, and middle cerebellar peduncle. Rs-fMRI analysis showed decreased functional connectivity in the interhemispheric dorsal attention network, and between the visual and cerebellar networks. The clinical severity of RTTs correlated with the volume reduction of the frontal lobe and cerebellum, and with changes in DTI indices in the fronto-occipital fasciculus, corpus callosum, and cerebellar peduncles.Regional volume and white matter integrity of RTT brains were reduced in broad areas, while most functional connections remained intact. Notably, two functional connectivities, between cerebral hemispheres and between the cerebrum and cerebellum, were decreased in RTT brains, which may reflect the structural changes in these brain regions.

X-ray pair distribution function (PDF) and Extended X-ray absorption fine structure (EXAFS) measurements were carried out on two Fe-based systems BaFe2As2 and LiFeAs to study mainly on the local structures of their FeAs planes. For the former system exhibiting the tetragonal (space group I4/mmm)-orthorhombic (Fmmm) structural phase transition at temperature TS ∼140 K, we show the T dependent characteristics of the local distortion from room temperature to the low temperature Fmmm phase, which support the existence of another local orthorhombic phase (I2mm) [Cantoni et al.: Adv. Mater. 27 (2015) 2715] at 300 K. We show the magnitudes of the local Fe atom shifts from their average Fe sites in these phases as the important information on what roles the lattice distortion has in the arguments on various physical properties of FeAs planes. For LiFeAs with the superconducting transition at ∼18 K but no structural transition, a small distortion has been found below 200 K.

A new oxyhydride CaVO3-xHx with ordered hydride anions was synthesized by topochemical reaction between hydrogen gas and oxygen-deficient perovskite, CaVO3-δ with ordered oxygen vacancies. The existence of hydride anions was confirmed by 1H nuclear magnetic resonance (NMR) measurements. Hydride anions occupy the oxygen vacancy sites of CaVO3-δ, forming VO4H2 octahedra with cis-geometry and a four-row chain made of cis-VO4H2 octahedra running along the [110] direction of the cubic perovskite structure. The four-row chains are ordered in a unique manner with a long periodicity. The temperature dependence of the shift of 1H-NMR spectrum well fits to the temperature dependence of the magnetic susceptibility, which reveals that hydride anions monitor the magnetic property of this oxyhydride.

The increasing frequency of fire due to drainage of tropical peatland has become a major environmental problem in Southeast Asia. To clarify the effects of changes in land use on carbon dioxide emissions, we measured oxidative peat decomposition (PD) at different stages of disturbance at three sites in Central Kalimantan, Indonesia: an undrained peat swamp forest (UF), a heavily drained peat swamp forest (DF), and a drained and burned ex-forest (DB). PD exhibited seasonality, being less in the wet season and greater in the dry season. From February 2014 to December 2015, mean PD (± SE) were 1.90 ± 0.19, 2.30 ± 0.33, and 1.97 ± 0.25 μmol m[-2] s[-1] at UF, DF, and DB, respectively. The groundwater level (GWL) was a major controlling factor of PD at all sites. At UF and DF, PD and GWL showed significant quadratic relationships. At DB, PD and GWL showed significant positive and negative relationships during the dry and wet seasons, respectively. Using these relationships, we estimated annual PD from GWL data for 2014 and 2015 as 698 and 745 g C m[-2] yr[−1]at UF (mean GWL: − 0.23 and − 0.39 m), 775 and 825 g C m[-2] yr[−1] at DF (− 0.55 and − 0.59 m), and 646 and 748 g C m[-2] yr[−1] at DB (− 0.22 and − 0.62 m), respectively. The annual PD was significantly higher in DF than in UF or DB, in both years. Despite the very dry conditions, the annual PD values at these sites were much lower than those reported for tropical peat at plantations (e.g., oil palm, rubber, and acacia). The differences in the relationship between PD and GWL indicate that separate estimations are required for each type of land. Moreover, our results suggest that PD can be enhanced by drainage both in forests and at burned sites.

The activation of phosphatidylinositol 3-kinase–AKTs–mammalian target of rapamycin cell signaling pathway leads to cell overgrowth and abnormal migration and results in various types of cortical malformations, such as hemimegalencephaly (HME), focal cortical dysplasia, and tuberous sclerosis complex. However, the pathomechanism underlying abnormal cell migration remains unknown. With the use of fetal mouse brain, we performed causative gene analysis of the resected brain tissues from a patient with HME and investigated the pathogenesis. We obtained a novel somatic mutation of the MTOR gene, having approximately 11% and 7% mutation frequency in the resected brain tissues. Moreover, we revealed that the MTOR mutation resulted in hyperphosphorylation of its downstream molecules, S6 and 4E-binding protein 1, and delayed cell migration on the radial glial fiber and did not affect other cells. We suspect cell-autonomous migration arrest on the radial glial foot by the active MTOR mutation and offer potential explanations for why this may lead to cortical malformations such as HME.

Recent evidence suggests that epithelial-mesenchymal transition (EMT) is involved in the pathogenesis of airway obstructive diseases, such as chronic obstructive pulmonary disease, asthma and bronchiolitis obliterans syndrome after lung transplantation. However, whether EMT occurs in an experimental model of airway fibrosis is not well known. We explored evidence of EMT in a murine model of airway fibrosis induced by repeated exposure to naphthalene. Mice were administered intraperitoneal injections of naphthalene or corn oil vehicle once weekly for 14 consecutive weeks. The animals were sacrificed 5days after the final injection of naphthalene or corn oil vehicle. EMT was evaluated in lung tissue sections using immunohistochemistry and immunofluorescence. Repeated naphthalene exposure induced loss of club cells, hyperplasia of epithelial cells and peribronchial fibrosis. However, we did not find any loss of E-cadherin expression or any acquisition of vimentin, S100A4 or αSMA in epithelial cells in control or naphthalene-exposed mice. These results suggest that EMT does not contribute significantly to naphthalene-induced airway fibrosis in mice.

SummaryRett syndrome (RTT) is a neurodevelopmental disorder caused by MECP2 mutations. Although emerging evidence suggests that MeCP2 deficiency is associated with dysregulation of mechanistic target of rapamycin (mTOR), which functions as a hub for various signaling pathways, the mechanism underlying this association and the molecular pathophysiology of RTT remain elusive. We show here that MeCP2 promotes the posttranscriptional processing of particular microRNAs (miRNAs) as a component of the microprocessor Drosha complex. Among the MeCP2-regulated miRNAs, we found that miR-199a positively controls mTOR signaling by targeting inhibitors for mTOR signaling. miR-199a and its targets have opposite effects on mTOR activity, ameliorating and inducing RTT neuronal phenotypes, respectively. Furthermore, genetic deletion of miR-199a-2 led to a reduction of mTOR activity in the brain and recapitulated numerous RTT phenotypes in mice. Together, these findings establish miR-199a as a critical downstream target of MeCP2 in RTT pathogenesis by linking MeCP2 with mTOR signaling.

Incorporation of 5-bromo-2′-deoxyuridine (BrdU) into proliferating cells has been used to label dividing cells in many tissues. Although BrdU has been shown to be genotoxic, teratogenic and mutagenic, such adverse effects have largely been ignored by researchers. We determined whether long-term BrdU exposure causes any histopathological changes in the lungs of mice. Eight-week-old male C57/BL6J mice were administered BrdU by intraperitoneal injection on 3 consecutive days of each week for 14 weeks. While no obvious structural changes such as tissue damage, fibrosis, emphysema, airway remodeling, vascular thickening or tumorigenesis were noted, a moderate degree of macrophage infiltration was observed in the airways and lung parenchyma in the lungs of the mice exposed repeatedly to BrdU (BrdU-exposed mice). The proliferative activities of the airway and alveolar epithelial and mesenchymal cells were reduced in the BrdU-exposed mice, although the numbers of these cells in the lungs were maintained. Double immunofluorescence study of the lungs of the BrdU-exposed mice showed overexpression of IL-6 in the airway epithelial and alveolar wall cells, some of which were also double-positive for BrdU. These results indicate that long-term exposure to BrdU inhibits cell proliferation and induces low-grade inflammation in the lungs of mice. Our findings underscore the need for caution in the interpretation of studies that involve long-term exposure to BrdU.

We studied the altered molecular species of lipids in brain and liver tissues, and fibroblasts from patients with Zellweger syndrome (ZS). ZS cerebellum samples contained a higher amount of sphingomyelin with shorter chain fatty acids compared to that in normal controls. The amount of phosphatidylethanolamine (PE) was less than half of that in controls, with the absence of the PE-type of plasmalogen. Gangliosides were accumulated in the brains and fibroblasts of ZS patients. To investigate whether or not impaired beta-oxidation of very long chain fatty acids and/or plasmalogen synthesis affects glycolipids metabolism, RNAi of peroxisomal acylCo-A oxidase (ACOX1) and glyceronephosphate O-acyltransferase (GNPAT) was performed using cultured neural cells. In neuronal F3-Ngn1 cells, ACOX1 and GNPAT silencing up-regulated ceramide galactosyltransferase (UGT8) mRNA expression, and down-regulated UDP-glucose ceramide glucosyltransferase (UGCG). These results suggest that both impaired beta-oxidation of very long chain fatty acids and plasmalogen synthesis affect glycolipid metabolism in neuronal cells.

Purpose: To describe operative procedures, seizure control and complications of surgery for cortical dysplasia (CD) causing intractable epilepsy in infancy and early childhood. Methods: Fifty-six consecutive children (less than 6 years old) underwent resective epilepsy surgery for CD from December 2000 to August 2011. Age at surgery ranged from 2 to 69 months (mean 23 months) and the follow-up was from 1 to 11 years (mean 4 years 4 months). Results: Half of the children underwent surgery during infancy at an age less than 10 months, and the majority (80%) of these infants needed extensive surgical procedures, such as hemispherotomy and multi-lobar disconnection. Seizure free (ILAE class 1) outcome was obtained in 66% of the cases (class 1a; 55%): 85% with focal resection (n = 13), 50% with lobar resection (n = 18), 71% with multilobar disconnection (n = 7) and 67% with hemispherotomy (n = 18). Peri-ventricular and insular structures were resected in 23% of focal and 61% of lobar resections. Repeated surgery was performed in 9 children and 5 (56%) became seizure free. Histological subtypes included hemimegalencephaly (16 patients), polymicrogyria (5 patients), and FCD type I (6 patients), type IIA (19 patients), type IIB (10 patients). Polymicrogyria had the worst seizure outcome compared to other pathologies. Surgical complications included 1 post-operative hydrocephalus, 1 chronic subdural hematoma, 2 intracranial cysts, and 1 case of meningitis. No mortality or severe morbidities occurred. Conclusions: Early surgical intervention in children with CD and intractable seizures in infancy and early childhood can yield favorable seizure outcome without mortality or severe morbidities although younger children often need extensive surgical procedures.

Methyl CpG-binding protein 2 gene (MeCP2) mutations are implicated in Rett syndrome (RTT), one of the common causes of female mental retardation. Two MeCP2 isoforms have been reported: MeCP2_e2 (splicing of all four exons) and MeCP2_e1 (alternative splicing of exons 1, 3, and 4). Their relative expression levels vary among tissues, with MeCP2_e1 being more dominant in adult brain, whereas MeCP2_e2 is expressed more abundantly in placenta, liver, and skeletal muscle. In this study, we performed specific disruption of the MeCP2_e2-defining exon 2 using the Cre-loxP system and examined the consequences of selective loss of MeCP2_e2 function in vivo. We performed behavior evaluation, gene expression analysis, using RT-PCR and real-time quantitative PCR, and histological analysis. We demonstrate that selective deletion of MeCP2_e2 does not result in RTT-associated neurological phenotypes but confers a survival disadvantage to embryos carrying a MeCP2_e2 null allele of maternal origin. In addition, we reveal a specific requirement for MeCP2_e2 function in extraembryonic tissue, where selective loss of MeCP2_e2 results in placenta defects and up-regulation of peg-1, as determined by the parental origin of the mutant allele. Taken together, our findings suggest a novel role for MeCP2 in normal placenta development and illustrate how paternal X chromosome inactivation in extraembryonic tissues confers a survival disadvantage for carriers of a mutant maternal MeCP2_e2 allele. Moreover, our findings provide an explanation for the absence of reports on MeCP2_e2-specific exon 2 mutations in RTT. MeCP2_e2 mutations in humans may result in a phenotype that evades a diagnosis of RTT.

A 26-year-old woman with psychomotor developmental delay since late infancy showed rapid deterioration of her psychomotor abilities at the 11 years of age. She had gained the ability to verbally express herself and perform motor activities such as running and dancing in early childhood, but she lost the ability to verbally communicate and was unable to walk independently after this period. She also presented with dystonia in the right extremities, which markedly fluctuated with a periodicity of hours to months. Sleep disturbance and epileptic seizures also emerged during adolescence. Frontal lobe atrophy and hypoperfusion of the left cerebral hemisphere were noted on neuroimaging examinations. Analysis of the MECP2 gene revealed a late truncating mutation of c.1196_1200delCCACC (p.P399QfsX4) near the 3'-terminal of the coding region. The phenotype of this patient corresponds to the rare, unestablished variant of "late childhood deterioration" in MECP2-related disorders. For the first time, MECP2 mutation was confirmed to be the genetic basis of this condition.

In order to analyze the mitigation of methane (CH 4 ) emissions and the global warming potentials (GWPs) of CH 4 and nitrous oxide (N 2 O) emissions from paddy fields by modifying the adopted water-management technique, we conducted field experiments to measure the CH 4 and N 2 O fluxes at nine sites across Japan. Over 2 years, we tested different water-management strategies such as prolonged midseason drainage (MD) in each site. The CH 4 emission rates at each site varied considerably; the rates were dependent on the ratio of reductive and oxidative capacities of the fields. Seasonal CH 4 emission was effectively reduced at most sites by prolonging MD beyond its conventional duration, especially at sites where organic matter was added to the soil before the cultivation. We attribute this result to the effective suppression of the CH 4 emission peak that occurs early in the cultivation period. Despite the large variation in seasonal CH 4 emissions among the sites, the rate of CH 4 emission resulting from alternative water-management strategies relative to that resulting from conventional water-management strategies is highly dependent on the degree of drainage during the MD period. N 2 O emission at most sites, in terms of GWP-based CO 2 -equivalent, was much smaller than that of CH 4 emission. Compared to conventional water-management strategies, the seasonal CH 4 emissions and the net 100-year GWPs (CH 4 + N 2 O) can be suppressed to 69.5 ± 3.4 (SE)% and 72.0 ± 3.1% while maintaining grain yields as high as 96.2 ± 2.0% by prolonging MD on average by employing the selected alternative water-management strategies that satisfied the following conditions: the percent of CH 4 emission of alternative water-management strategies was less than 90% and the grain yield was greater than 85% relative to conventional water-management strategies.

Virtually all reliable TEM tomographic reconstructions in life science depend upon cross-correlating successive images in a tilt-stack, and then using gold nanobeads as fiducial markers for determining the relative image rotation axis. Although the rotational tilt angle is one of the essential parameters affecting the quality of tomographic reconstructions, little is discussed about its determination. We provide here a simple tool based on the property of Fast Fourier Transformation for determining this rotation axis offset angle. Our method uses two publicly-available software packages (IMOD and ImageJ), and can be used on any TEM-based image stack, which is useful for images with poor bead distribution or situations where such beads are not visible. We illustrate this procedure with two different biological samples, one of which is a plunge frozen cryo-sample with fiducials and the other an epon-embedded thin section without fiducials. Prior knowledge of the rotational tilt angle facilitates further processing tomograms. With cross-correlation and the FFT-obtained rotational tilt angle, we reconstructed tomograms, of which the cross-section did not show "arc" distortion. This tool could be easily incorporated into any software for the alignment with or without fiducials.

A 3-year-old boy with right hemimegalencephaly (HME) showed massive calcification in the subcortical white matter and progressive atrophy of the affected hemisphere. Hemispherotomy was successful in amelioration of the patient's intractable epilepsy, and a surgical specimen from the epileptic focus was examined pathologically. Disarrangement of cortical layers along with dysmorphic appearance of neurons, balloon cells in the cortex and white matter, bi-layered calcifications in the superficial cortical layer and subcortical white matter, heterotopic neurons in the white matter, and diffuse astrogliosis were noted. Perivascular clustering of alpha-B-crystallin positive balloon cells was occasionally observed in the area of calcification. A diffuse increase was observed in the number of CD68-positive microglia/macrophages, particularly in perivascular and peri-calcification areas. These cells were often located within the calcification foci, which implicates their participation in the calcification process. Phosphorylated S6 ribosomal protein (P-S6) was expressed in large-sized neurons and numerous balloon cells, as well as in CD68-positive cells. In contrast, phosphorylated mammalian target of rapamycin (mTOR) was expressed in a small percentage of astrocytes, and phosphorylated p70S6 kinase was rarely identified in perivascular cells. These findings suggest that inflammatory processes have contributed to the pathogenesis of progressive calcification and atrophy in the megalencephalic hemisphere in this patient. Dissociation of expression of mTOR cascade components is common to other reported cases of HME, but P-S6 expression in microglia/macrophages has not been recognized. The cellular mechanism and significance of P-S6-specific activation of the mTOR cascade in HME, particularly in the inflammatory cell lineage, should be explored further.

Methane (CH4) uptake by soil can possibly be suppressed more in regions with heavy summer precipitation, such as those under the East Asian monsoon climate, as compared to that in regions with a dry summer. In order to determine how precipitation patterns affect seasonal and spatial variations in CH4 fluxes in temperate forest soils, such fluxes and selected environmental variables were measured on different parts of a hill slope in a cypress forest in central Japan. On the upper and middle parts of the slope, CH4 uptake was observed throughout the year, and the uptake rates increased slightly with soil temperature and decreased with soil water content. The CH4 flux predicted using data for the middle and upper parts of the slope ranged from −1.12 to −0.83 kg-CH4 ha−1 y−1 (i.e. CH4 uptake by soil) and from −2.30 to −2.04 kg-CH4 ha−1 y−1, respectively. In contrast, in the relatively wet lower part of the slope near an in-stream wetland, large CH4 emissions (>2 mg-CH4 m−1 d−1) were observed during the rainy summer. In this wetter plot, the soil functioned as a net annual CH4 source in a rainy year. Hence the variation in CH4 flux with a change in soil water conditions and soil temperature on the lower part of the slope contrasted to that on the upper and middle parts of the slope. The predicted CH4 flux for this lower plot ranged from −0.45 kg-CH4 ha−1 y−1 in a dry year to 1.80 kg-CH4 ha−1 y−1 in a rainy year. Our results suggest that consideration of the soil water conditions across a watershed is important for estimating the CH4 budgets for entire forest watershed, particularly in regions subject to a wet summer.

To elucidate the neuropathological mechanism of Zellweger syndrome (ZS), we studied changes in the molecular species of glycerophospholipids in the cerebral tissue by thin-layer chromatography (TLC) and fast atom bombardment mass spectrometry (FABMS). First, we estimated the amount of plasmalogens by TLC. Plasmalogen-type phosphatidyl ethanolamine (PE) accounted for 30% of the total PE in the control brain, but was absent in the ZS brain. Plasmalogen-type phosphatidyl choline (PC) was undetectable in both control and ZS brains. Next, we analyzed plasmalogen-type PE by FABMS. Oleic (18:1), arachidonic (20:4) and docosapentanoic (22:5) acids were present in the control gray matter, but not in the ZS gray matter. In compensation for the defect of plasmalogen, the level of diacyl PE with polyunsaturated fatty acids, 20:4, 22:4, 22:5 and 22:6, was higher in the ZS brain than that in the control brain. These results indicate an alteration in the molecular species of PE, which may cause abnormal neural membrane fluidity and excessive vulnerability to oxygen stress.

The lipid composition and molecular species of phospholipids were examined in the brain of a patient with Zellweger syndrome (ZS), and were compared with those of control infants. In the cerebral gray matter of the ZS patient, the amounts of ceramide monohexoside and cholesterol ester were larger than those of controls. By contrast, the amount of ceramide monohexoside in the white matter was smaller in the ZS patient than that in the age-matched control. Although the amount of phosphatidylcholine (PC) plus phosphatidylserine (PS) was the same, dipalmitoyl PC and PS were increased in both the gray and white matter of the ZS cerebrum. These alterations in the molecular species of brain lipids may play crucial roles in the pathogenesis of ZS.

Nestin is a cytoskeletal protein expressed by neural stem cells, and by immature neurons and glial cells. In an effort to explore the potential of the infant brain for repair and plasticity, we immunohistochemically studied nestin expression in the human cerebral cortex of control subjects and of patients with periventricular leukomalacia. During normal development, nestin immunoreactivity of the cortical gray and white matter was detectable throughout the fetal period, and disappeared around birth. In brain with periventricular leukomalacia, nestin expression was altered in a time- and space-dependent manner. In the cortical gray matter, neuronal immunoreactivity was often reduced in the subacute stage, but was increased in chronic and remote stages. In the white matter near a lesion of periventricular leukomalacia, glial immunoreactivity was increased in all stages. In many cases, neurons and axons far from a lesion also showed an altered expression of nestin. These findings indicate that in brain with periventricular leukomalacia, neurons and glial cells may recapitulate nestin expression in response to ischemic brain injury, suggesting functional relevance in repair and plasticity.

Perinatal hypoxic-ischemic brain damage is a major cause of neuronal and behavior deficits, in which the onset of injury can be before, at or after birth, and the effects may be delayed. Pontosubicular neuron necrosis (PSN) is one of perinatal hypoxic-ischemic brain injury and its pathological peculiarity is neuronal apoptosis. In this study, we investigated whether apoptotic cascade of PSN used a caspase-pathway or not, and whether hypoglycemia activated apoptosis or not. Sections of the pons of PSN with and without hypoglycemia were stained using terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) and immunohistochemistry for glial fibrillary acidic protein (GFAP), Bcl-2, Bcl-x and activated caspase 3. Additionally, we performed immunoblot analysis of Bcl-2, Bcl-x and activated caspase 3. TUNEL-positive cell was closely associated with the presence of karyorrhexis. Under combination of karyorrhectic and TUNEL-positive cells, number of apoptotic cells in premature brains was significantly more than in mature brains. Hypoxic-ischemic brain injury was considered to easily lead to apoptosis in premature infants. Moreover, as this pathophysiology, caspase-pathway activation contributed to neuronal death from caspase-immunoexpression analyses. PSN with hypoglycemia showed large number of apoptotic cells and higher expression of activated caspase 3. The result may be more severe with the background of hypoglycemia and prematurity complicated by hypoxia and/or ischemia.

The lung could be the target organ to cellular damage, since it is directly exposed to high concentrations of oxygen. Acute exercise and age would be an added challenge to the lung, and therefore, we investigated alterations of major lung antioxidant enzymes (manganese-superoxide dismutase, Mn-SOD; cupper–zinc-SOD, Cu–Zn-SOD; glutathione peroxidase, GPX; catalase, CAT) activities and mRNA expressions in young (4 months old) and old (26 months old) male Wistar rats with exercise. Thioredoxin reductase (TrxR) activity was also investigated. Mn-SOD and Cu–Zn-SOD increased with age, but age did not affect GPX, CAT, or TrxR activity. Acute exercise in young animals increased the activities of Mn-SOD, Cu–Zn-SOD, and CAT. In contrast, only Mn-SOD increased significantly in the old animals. The mRNA expressions of Mn-SOD, Cu–Zn-SOD and GPX were not altered with age, while CAT mRNA expression decreased with age. Acute exercise had no significant effect on any of the antioxidant enzyme mRNA expression. Moreover, reactive carbonyl derivative increased with age, but no significant changes were detected after acute exercise in either group. In summary, antioxidant enzymes responsible for the removal of hydrogen peroxide were unable to increase their enzyme activities in the old animals with exercise.

To clarify whether Mecp2 dysfunction may cause impairment of the monoaminergic and serotonergic systems, we measured the whole brain concentrations of biogenic amines and related substrates in three mecp2 -null male mice and four control mice of each age at 0–42 postnatal days by HPLC methods. After 14 postnatal days, concentrations of biogenic amines were smaller in mecp2 -null mice than those in control mice and at 42 postnatal days, norepinephrine, dopamine and serotonin concentrations in mecp2 -null mice were significantly smaller by 25, 24 and 16%, respectively. This result suggested that the absence of Mecp2 does not impair the neurogenesis of monoaminergic and serotonergic neurons but causes succeeding impairment of those neuronal systems from 14 postnatal days.

We identified eight genes of putative RGS proteins in skin of Medaka fish using PCR amplification with degenerate primers for the RGS domain of known RGS proteins. Then, we cloned a full-length cDNA for a new RGS protein. This RGS protein was similar to human RGS3 within the RGS domain, but other parts were unique among known RGS proteins. RT-PCR analysis demonstrated that this Medaka RGS3-like protein (MeRGS3L) is mainly expressed in skin and heart. When coexpressed in Xenopus oocytes, MeRGS3L accelerated the turning-on and -off of Gi/o-mediated modulation of GIRK channels without apparent desensitization in the presence of ligand. MeRGS3L also decreased the response of Gq signaling upon activation of m1 muscarinic receptor. This new RGS protein may play important roles in regulation of melanophore responses in Medaka skin.

The features of 27 Al and 87 Rb NMR in Rb-loaded LTA-type zeolite are discussed in comparison with K-loaded one. Broadening of 27 Al spectrum by magnetic origin is observed and the difference from the K case is pointed out for the shape of spectrum. These facts suggest that the configurations of electrons are not identical in the cases of Rb and K. For 87 Rb the mass center of the spectrum shifts clearly to higher frequency side below 10 K . The existence of Fermi contact interaction between s electron and Rb nuclei is suggested.

RGS8 was originally identified as an RGS protein specifically expressed in neuronally differentiated P19 cells. We generated a polyclonal antibody specific to rat RGS8 using a synthetic peptide. When nonneural cells (DDT1MF2, CHO, and NIH3T3) transfected with rat RGS8 cDNA were immuno-stained with this antibody, the RGS8 protein was mainly detected in the nuclei. Since RGS8 mRNA was exclusively expressed in Purkinje cells of the cerebellum in the rat brain, we further examined the cellular distribution of the RGS8 protein in Purkinje cells using cultured cerebellar cells and tissue sections of the cerebellum. The RGS8 protein was excluded from the nuclei and distributed in the cell body and dendrites, but not in the axons of Purkinje cells. These results demonstrate the presence of a mechanism controlling the distribution of RGS8 protein in cerebellar Purkinje cells.

We studied the expression of the apoptosis-related protein, E2F-1, in Down's syndrome (DS) brains. The immunoreactivity for E2F-1 was detected in the pyramidal neurons of the cerebral cortex from DS brains exhibiting the neuropathological features of dementia of Alzheimer type (DAT), in accordance with the amyloid beta protein (A beta) deposition in the neuron. Therefore, the implication is that A beta deposition may trigger E2F-1-mediated neuronal apoptosis in DS brains with DAT.

Using Green's function method, within the framework of the S =1/2 one-dimensional Heisenberg model with a next-nearest-neighbor competing interaction, the temperature dependences of 1/ T 1 and 1/ T 2G in the uniform state of the spin-Peierls compound CuGeO 3 have been calculated. The results reproduce the main features of the observed experimental behavior.

We have previously described the immunoreactivities of glutamate transporters, EAAT4 and GLAST, in the developing human cerebellum. In the present report, we demonstrate the different expression of EAAT4 and GLAST in the pathologic condition, neonatal subarachnoid hemorrhage. EAAT4 and GLAST were characteristically disturbed in the cerebellar cortices beneath the subarachnoid hemorrhage. In preterm infants with subarachnoid hemorrhage the decrease in EAAT4 immunoreactivity was more prominent than in term infants, and GLAST immunoreactivity in the inner granular cell layer decreased and reappeared later than in term infants with subarachnoid hemorrhage. Although Bergmann's glia removes glutamate from the extracellular space surrounding Purkinje cells in the early stage of hypoxic-ischemic brain damage, the reaction of EAAT4 and GLAST in the cerebellar cortex under the subarachnoid hemorrhage was decreased, and immature glia had a delayed reaction. These characteristics of glutamate transporters in immature cells may lead to cell death and olivocerebellar degeneration.

Changes in dopamine transporter and neuronal nitric oxide synthase (nNOS) were investigated by immunohistochemistry in 18 cases of hypoxic-ischemic basal ganglia necrosis. Neuropil dopamine transporter immunostaining in the striatum was increased in seven cases, with relatively mild basal ganglia necrosis, and decreased in four cases, with marked basal ganglia necrosis, compared with age-matched control subjects. Correspondingly, some striatal neurons had increased immunoreactivity to dopamine transporter in the cases of increased immunostaining in the neuropil. nNOS-positive neurons did not obviously change in cases of basal ganglia necrosis within 2 days after birth and then decreased or were not detectable in cases of basal ganglia necrosis at more than 3 days after birth. The results suggest that the synthesis of dopamine transporter is up-regulated in relatively mild basal ganglia necrosis to compensate for the uptake of increased dopamine, that this compensative ability is lost in marked basal ganglia necrosis, and that nNOS-containing neurons in the striatum are relatively resistant to hypoxic ischemia. We speculate that glutamate excitotoxicity mediated by glutamate receptors 1, 2/3, and 4 and excessive dopaminergic excitatory activity may play important roles in hypoxic-ischemic basal ganglia necrosis and that nNOS does not contribute to that condition.

Effects of growth rate on metalorganic molecular beam epitaxy (MOMBE) growth of 2.1% compressive strained InAsP-multi-quantum wells (MQWs) was investigated using photoluminescence (PL), double-crystal X-ray diffraction (DCXRD) analysis and cross-sectional transmission electron microscopy (XTEM). As the growth rate of a well layer increases from 0.17 to 0.33 nm/s, the PL intensity increases remarkably and the width of satellite peaks in the DCXRD spectra becomes narrower. The amplitude of a well layer surface undulation, ascertained by XTEM, decreases as the growth rate increases, simultaneously. This indicates that increasing of the PL intensity and narrowing of the satellite peak width are attributed to decreasing of amplitude of the well layer surface undulation caused by increasing the growth rate. Utilizing this finding, we can increase the number of strained InAsP wells up to 20 without any evidence of material degradation due to well layer surface undulation. In addition, we fabricated buried heterostructure MQW lasers emitting a 1.56 μm wavelength light with a low threshold current of 7.0 mA and a large differential gain of 9.0×10 −16 cm 2 .

The 23Na nuclear spin–lattice relaxation rate 1 / T 1 has been measured to study the Na order–disorder transition in the quasi-one-dimensional conductor β - Na 0.33 V 2 O 5 . From the analysis of 1 / T 1 based on the Bloembergen–Purcell–Pound theory, we conclude that the hopping motion of a Na atom between the neighboring Na positions with the barrier energy of ∼ 940 K is suppressed by the order–disorder transition.

7Li and 51V NMR measurements have been made to study the electronic structure and the local magnetic properties of the quasi-one-dimensional conductor β - Li 0.33 V 2 O 5 . We found that the Li order–disorder transition takes place above 300 K. From the analysis of the 51V Knight shifts, we estimate local magnetic susceptibilities and discuss the electronic structure in the metallic phase.

We have performed 59 Co NMR measurements to study the metamagnetic transition at 4.2 K in intermetallic compounds Y1−xNdxCo3 (0⩽x⩽1) and Y1−xGdxCo3 (0⩽x⩽0.32). We observed 59Co NMR signals coming from the three nonequivalent Co sites and found from an analysis of the NMR spectra that successive metamagnetic transitions were induced by the exchange field of the Nd and Gd magnetic moments without an external magnetic field. The Co magnetic moments at the 3b and 6c (18h) sites undergo the metamagnetic transition around x=0.35 (0.85) in Y1−xNdxCo3 at 4.2 K in zero external field. On the other hand, metamagnetic transitions of Co magnetic moments at the three sites take place around x=0.25 in Y1−xGdxCo3. The exchange constants between the Co spins at the three Co sites and the R (R=Nd and Gd) spins are estimated for both systems.

V 51 and Na 23 NMR measurements under high pressures have been made on a single crystal to study microscopically the pressure versus temperature phase diagram in the quasi-one-dimensional superconductor β - Na 0.33 V 2 O 5 . We are successful in observing V 51 and Na 23 NMR spectra up to ∼ 6.2 GPa in the temperature range 2–300 K. We determine from the NMR spectrum changes the boundaries between the metallic and insulating phases and between the paramagnetic and antiferromagnetic ones. They are consistent with the phase diagram proposed from the resistivity and susceptibility measurements.

23 Na NMR measurements have been made on a single crystal to study the local symmetry and the electronic state in the quasi-one-dimensional conductor β - Na 0.33 V 2 O 5 . We observed the characteristic 23 Na NMR spectra in the metallic and insulating phases. The characteristic spectra are well explained by the lattice symmetry proposed by the X-ray diffraction and the neutron scattering studies. From the analysis of the 23 Na Knight shift, we find that the metal-insulator (MI) transition is accompanied not by the charge ordering (CO) of V 4 + and V 5 + but by the charge disproportionation (CD). A model of the electronic structure is proposed in the insulating phase.

V 51 NMR measurements have been made on a single crystal to study the spin gap in the vanadium bronze η - Na 1.286 V 2 O 5 . We observe four sets of V 51 NMR spectra coming from the nonmagnetic V1 and V2 sites above T 0 ∼ 110 K and eight sets below T 0 due to the doubling of the V1 and V2 sites accompanied by the structural transition. The V 51 Knight shift measurements for the V1 and V2 sites indicate that the magnetic vanadium sites show the spin-gap behavior with the gap energy dependent on the vanadium sites below T 0 .

Co 59 NMR measurements have been performed to study the local magnetic properties of the thermoelectric material [ Ca 2 CoO 3 ] 0.62 [ CoO 2 ] . We observe the changes in the Co 59 NMR spectra corresponding to the phase diagram proposed by the μ SR and magnetization measurements. The Co 59 NMR spectrum at 4.2 K under zero external field shows the presence of the several Co sites which may come from the Co sites in the Ca 2 CoO 3 layer.

Structural and optical properties of the compressively strained multiple quantum wells (MQWs), where InAsP well layer strain ranges from 1.9–2.15%, have been studied. Transmission electron microscopy reveals that 1.9%-strained MQWs have flat interfaces whereas 2.15%-strained MQWs have wavy interfaces as growth proceeds. The 1.9%-strained MQW photoluminescence (PL) intensities stay quite strong in the barrier tensile strain range of 0–0.4% but are reduced by 90% in the 0.6–0.9% range, i.e. strain compensation is not useful in the highly strained MQWs. A new type of MQW structure, where a thin compositional-graded InAs x P 1− x layer is inserted between the well and the barrier layers, provides six-well MQWs having high PL intensities. These results show that the shearing stress at the well–barrier interface rather than net strain plays an important role in growing the 1.9%-strained MQWs. We have fabricated the buried heterostructure MQW lasers emitting at a 1.5 μm wavelength light with a low threshold current of 6.5 mA and a large differential gain of 9.3×10 −16 cm 2 .

Two types of noise from the variable landing-energy focused-ion-beam (FIB) system appeared when FIB was line-scanned on an n-GaAs wafer and implantation-induced damage was estimated by using selective etching and secondary electron microscope (SEM) observation. The first had a rough surface with small craters away from implanted lines and the second had clearly observable scratchiness along implanted lines. Cathode luminescence measurement and auger analysis were performed to estimate beam-tail spreading. Both the long-beam-tail and the scratchy noise probably originated from unintentionally scattered beams in the ion-beam lens column and/or neutral particles emitted from the liquid metal ion source. As a result, these noises could be greatly reduced by locating a new aperture at an appropriate position. Using this refined FIB system, low landing-energy-ion-beams should be able to be applied to fabricate high-quality mesoscopic devices.

We analyze results of a approx.25 ksec ASCA X-ray observation of the unusual Wolf-Rayet star HD 50896 (= EZ CMa). This WN5 star shows optical and ultraviolet variability at a 3.766 day period, which has been interpreted as a possible signature of a compact companion. Our objective was to search for evidence of hard X-rays (greater than or equal to 5 keV) which could be present if the WN5 wind is accreting onto a compact object. The ASCA spectra are dominated by emission below 5 keV and show no significant emission in the harder 5-10 keV range. Weak emission lines are present, and the X-rays arise in an optically thin plasma which spans a range of temperatures from less than or equal to 0.4 keV up to at least approx. 2 keV. Excess X-ray absorption above the interstellar value is present, but the column density is no larger than N(sub H) approx. 10(exp 22)/sq cm. The absorption-corrected X-ray luminosity L(sub x)(0.5 - 10 keV) = 10(exp 32.85) erg/s gives L(sub x)/ L(sub bol) approx. 10(exp -6), a value that is typical of WN stars. No X-ray variability was detected. Our main conclusion is that the X-ray properties of HD 50896 are inconsistent with the behavior expected for wind accretion onto a neutron star or black hole companion. Alternative models based on wind shocks can explain most aspects of the X-ray behavior, and we argue that the hotter plasma near approx. 2 keV could be due to the WR wind shocking onto a normal (nondegenerate) companion.

We have studied metalorganic molecular beam epitaxy (MOMBE) of InGaAsP multi-quantum wells (MQWs) with 0.5-1.8% tensile-strained well layers. The MQW photoluminescence intensity depends significantly on the barrier layer strain to compensate well layer strain. Optimizing the strain compensation conditions, i.e., keeping the net strain less than 0.3%, makes it possible to grow high optical quality MQWs with 1.8%-strained, 10-well layers. A critical thickness-net strain (t c -e*) curve for the tensile-strained MQWs has been experimentally determined by analyzing more than 50 samples with various strains and total thicknesses. The t c -e* curve fairly agrees with the one calculated by the Matthews formula for more 0.5% net strain, but the t c values are much higher than the expected ones below that range. For 6-well MQW lasers, the threshold current densities, J th 's, decrease with increasing tensile strain; the minimum J th obtained is 0.6 kA/cm 2 at 1.3% strain.

We have observed sudden clinical death due to Fukuyama-type congenital muscular dystrophy (FCMD). In FCMD, brain abnormalities, such as polymicrogyria, leptomeningeal neuroglial heterotopia and abnormal course of the corticospinal tracts, are well known. We investigated the brainstem of 10 FCMD and 7 control cases. Among the control cases, 5 with Duchenne type muscular dystrophy died of heart failure and 2 died accidental death. In the brainstem, the catecholaminergic neurons characterized by reaction with antiserum to tyrosin hydroxylase showed notable reduction in the reticular formation, vagal nuclei, and nucleus tractus solitarius. Delays or aberrations of neural control may contribute to the pathogenesis of sudden infant death syndrome, and medullary gliosis occurs in the reticular formation of sudden infant death syndrome. The pathogenesis of neurons in the brainstem in FCMD may be similar to that in sudden infant death syndrome. These findings suggest neuronal dysfunction in the brainstem and may be related to respiratory, circulatory, or sleep-wake regulation disorders.

Cyclic triaxial tests have been carried out on a skeletal carbonate sand from the west coast of Eire. Results are presented for undrained cyclic shear tests on samples with 80% of relative density consolidated under both isotropic and anisotropic conditions. Failure was defined as a 5% double amplitude cyclic strain and a 5% peak axial strain for stress-reversal and non-reversal stress conditions, respectively. Using this definition the cyclic strength for isotropically consolidated samples was affected by the confining pressure although the angular platey nature of the sand resulted in higher cyclic strengths than for a comparable silica sand. For anisotropically consolidated samples the cyclic strength increased with increasing initial static shear stress while on the other hand the cyclic strength normalised in the usual way with respect to the initial confining pressure decreased as this pressure increased.

Experiments were made to determine the dependence of the size of contact-free nanoparticles produced by aerosol process on gas pressure. The particles were collected as contact-free dispesoids in hexane with a cationic surfactant, and the geometric mean sizes were below 10 nm in diameter. It was found that the size increased linearly as the pressure was raised from 0.04 to 1.43 kPa for Ag, Bi, Cu, and Te. Similar slopes were obtained for the linear function between size and gas pressure except for Te.

Recently, the orbital degree of freedom has attracted renewed interest in strongly correlated electron systems. The RTiO3 (R: rare earths) system is one of the attracting systems in the study of the orbital degree of freedom. While an orbital ordering state is observed in a ferromagnet YTiO3, no orbital ordering has yet been observed in an antiferromagnet LaTiO3. In this study, we have measured 47,49 Ti NMR spectra of RTiO3 (R=Y, Gd, and La). We investigate the orbital state by analyzing the NMR spectra of RTiO3.

In children with moyamoya disease, the time courses of hemoglobin concentrations before and after hyperventilation were examined using near-infrared spectrophotometry (NIRS) to determine brain tissue oxygenation. Five patients were studied: 1 was studied both before and after surgery and 4 were studied only after surgery. Nine hemispheres of these 5 patients were examined. The oxygenated hemoglobin concentration increased immediately after beginning hyperventilation. This parameter later decreased sharply to below the prehyperventilation level and remained at the reduced level for a prolonged period. These changes in oxygenated hemoglobin concentration were similar to those previously reported in arterial blood oxygen and CO2 tension. The magnitude of variance in oxygenated hemoglobin concentration (C-HV) was significantly greater in moyamoya disease patients than in healthy controls (P < .003, Wilcoxon test). The changes of NIRS after operation were markedly more sensitive than those of electroencephalography or single-photon emission computed tomography. NIRS could be applied to cerebral oxygenation as well as cerebral hemodynamics, which may be used to better define the time sequence and pathologic processes of various childhood encephalopathies.

High-number-density, contact-free nanophase silver particles were prepared in hexane. The particles were produced by an evaporation/condensation aerosol process, trapped in an organic solvent, coated with a surfactant, and then concentrated. A highly concentrated state (1018–1019 particles m−3) could be achieved in hexane for particles with 7 nm mean diameter. The changes in particle size and agglomeration during processing were determined from electron microscopy and photon correlation spectroscopy. The surfactant coating of the particle surface effectively prevented fusion of the nanophase particles. The advantage of this method was confirmed by the size preservation of the particle size distribution after deflocculation from the coagulums which had formed upon concentrating the solution.