Case Report: Severe Osteoporosis and Preventive Therapy in RNA Polymerase III-Related Leukodystrophy.

RNA polymerase III (POLR3)-related leukodystrophy is an autosomal recessive form of leukodystrophy caused by homozygous or compound heterozygous mutations of the RNA polymerase III subunit genes, including subunit A (POLR3A). With respect to the manifestation triad, hypomyelination, hypodontia, and hypogonadotropic hypogonadism, it is also known as 4H leukodystrophy. Here, we report a 41-year-old woman of POLR3-related leukodystrophy by carrying compound heterozygous pathogenic variants of c.2554A>G (p.M852V) and c.2668G>T (p.V890F) in the POLR3A gene. She was amenorrheic and became a wheelchair user from the age of 15 years and suffered from multiple episodes of pathologic fractures, starting with a subtrochanteric fracture of the right femur after a tonic seizure at age 30 years. Head magnetic resonance imaging demonstrated hypomyelination and atrophies of the cerebellum, brainstem, and corpus callosum. Laboratory examination revealed a marked decrease of gonadotropins and estrogen, low bone density, and high bone resorption markers. Administration of anti-receptor activator of nuclear factor kappa-B ligand monoclonal antibody restored bone resorption markers to a normal level and prevented further pathological bone fractures. Our case emphasizes that osteoporosis should be recognized as a potential but serious complication in POLR3-related leukodystrophy. It may be feasible to prevent pathologic fractures by intensive osteoporosis therapy after endocrinological examinations and evaluation of bone metabolism.

Implementation and experiments for interactive lyrics transcreation system.

The evolution of the Internet has enabled us to enjoy the music created in various countries. But still, it is often difficult to understand the lyrics written in foreign languages. Professional translators have published many international songs with lyrics that fit the melody so that the ordinary people can enjoy the lyrics of such international songs. This paper discusses lyrics transcreation into the Japanese language. Also, the paper presents an interactive visual lyrics transcreation system and describes the details of its implementation. This system allows users to select temporary lyrics from a set of tentative translations and then freely modify the lyrics with a real-time visualization mechanism. We also propose a lyrics translation algorithm that solves an essential problem of lyrics translation into Japanese. In this study, we interviewed two experts regarding problems with lyrics translation and received reviews of our presented system. We also conducted preliminary experiments with 19 participants to determine the best combination of user interface components for our system. We performed additional user experiments inviting 12 participants to compare lyrics transcreation using the presented system to manual lyrics transcreation. Lyrics transcreation by the presented system brought better results against those of manual transcreation.

Streamline pair selection for comparative flow field visualization.

Fluid dynamics simulation is often repeated under varying conditions. This leads to a generation of large amounts of results, which are difficult to compare. To compare results under different conditions, it is effective to overlap the streamlines generated from each condition in a single three-dimensional space. Streamline is a curved line, which represents a wind flow. This paper presents a technique to automatically select and visualize important streamlines that are suitable for the comparison of the simulation results. Additionally, we present an implementation to observe the flow fields in virtual reality spaces.

Painting image browser applying an associate-rule-aware multidimensional data visualization technique.

Exploration of artworks is enjoyable but often time consuming. For example, it is not always easy to discover the favorite types of unknown painting works. It is not also always easy to explore unpopular painting works which looks similar to painting works created by famous artists. This paper presents a painting image browser which assists the explorative discovery of user-interested painting works. The presented browser applies a new multidimensional data visualization technique that highlights particular ranges of particular numeric values based on association rules to suggest cues to find favorite painting images. This study assumes a large number of painting images are provided where categorical information (e.g., names of artists, created year) is assigned to the images. The presented system firstly calculates the feature values of the images as a preprocessing step. Then the browser visualizes the multidimensional feature values as a heatmap and highlights association rules discovered from the relationships between the feature values and categorical information. This mechanism enables users to explore favorite painting images or painting images that look similar to famous painting works. Our case study and user evaluation demonstrates the effectiveness of the presented image browser.

The Sprawlter Graph Readability Metric: Combining Sprawl and Area-Aware Clutter.

Graph drawing readability metrics are routinely used to assess and create node-link layouts of network data. Existing readability metrics fall short in three ways. The many count-based metrics such as edge-edge or node-edge crossings simply provide integer counts, missing the opportunity to quantify the amount of overlap between items, which may vary in size, at a more fine-grained level. Current metrics focus solely on single-level topological structure, ignoring the possibility of multi-level structure such as large and thus highly salient metanodes. Most current metrics focus on the measurement of clutter in the form of crossings and overlaps, and do not take into account the trade-off between the clutter and the information sparsity of the drawing, which we refer to as sprawl. We propose an area-aware approach to clutter metrics that tracks the extent of geometric overlaps between node-node, node-edge, and edge-edge pairs in detail. It handles variable-size nodes and explicitly treats metanodes and leaf nodes uniformly. We call the combination of a sprawl metric and an area-aware clutter metric a sprawlter metric. We present an instantiation of the sprawlter metrics featuring a formal and thorough discussion of the crucial component, the penalty mapping function. We implement and validate our proposed metrics with extensive computational analysis of graph layouts, considering four layout algorithms and 56 layouts encompassing both real-world data and synthetic examples illustrating specific configurations of interest.

Differing intrinsic biological properties between forebrain and spinal oligodendroglial lineage cells.

Differentiation of oligodendroglial progenitor cells (OPCs) into myelinating oligodendrocytes is known to be regulated by the microenvironment where they differentiate. However, current research has not verified whether or not oligodendroglial lineage cells (OLCs) derived from different anatomical regions of the central nervous system (CNS) respond to microenvironmental cues in the same manner. Here, we isolated pure OPCs from rat neonatal forebrain (FB) and spinal cord (SC) and compared their phenotypes in the same in vitro conditions. We found that although FB and SC OLCs responded differently to the same external factors; they were distinct in proliferation response to mitogens, oligodendrocyte phenotype after differentiation, and cytotoxic responses to α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate-type glutamate receptor-mediated excitotoxicity at immature stages of differentiation in a cell-intrinsic manner. Moreover, transcriptome analysis identified genes differentially expressed between these OPC populations, including those encoding transcription factors (TFs), cell surface molecules, and signaling molecules. Particularly, FB and SC OPCs retained the expression of FB- or SC-specific TFs, such as Foxg1 and Hoxc8, respectively, even after serial passaging in vitro. Given the essential role of these TFs in the regional identities of CNS cells along the rostrocaudal axis, our results suggest that CNS region-specific gene regulation by these TFs may cause cell-intrinsic differences in cellular responses between FB and SC OLCs to extracellular molecules. Further understanding of the regional differences among OPC populations will help to improve treatments for demyelination in different CNS regions and to facilitate the development of stem cell-derived OPCs for cell transplantation therapies for demyelination. Cover Image for this issue: doi. 10.1111/jnc.13809.

Key-Node-Separated Graph Clustering and Layouts for Human Relationship Graph Visualization.

Many graph-drawing methods apply node-clustering techniques based on the density of edges to find tightly connected subgraphs and then hierarchically visualize the clustered graphs. However, users may want to focus on important nodes and their connections to groups of other nodes for some applications. For this purpose, it is effective to separately visualize the key nodes detected based on adjacency and attributes of the nodes. This article presents a graph visualization technique for attribute-embedded graphs that applies a graph-clustering algorithm that accounts for the combination of connections and attributes. The graph clustering step divides the nodes according to the commonality of connected nodes and similarity of feature value vectors. It then calculates the distances between arbitrary pairs of clusters according to the number of connecting edges and the similarity of feature value vectors and finally places the clusters based on the distances. Consequently, the technique separates important nodes that have connections to multiple large clusters and improves the visibility of such nodes' connections. To test this technique, this article presents examples with human relationship graph datasets, including a coauthorship and Twitter communication network dataset.

ZPK/DLK and MKK4 form the critical gateway to axotomy-induced motoneuron death in neonates.

Motoneuron death after transection of the axons (axotomy) in neonates is believed to share the same mechanistic bases as naturally occurring programmed cell death during development. The c-Jun N-terminal kinase pathway is activated in both forms of motoneuron death, but it remains unknown to what extent these two forms of motoneuron death depend on this pathway and which upstream kinases are involved. We found that numbers of facial motoneurons are doubled in neonatal mice deficient in either ZPK/DLK (zipper protein kinase, also known as dual leucine zipper kinase), a mitogen-activated protein kinase kinase kinase, or in MKK4/MAP2K4, a mitogen-activated protein kinase kinase directly downstream of ZPK/DLK, and that the facial motoneurons in those mutant mice are completely resistant to axotomy-induced death. Conditional deletion of MKK4/MAP2K4 in neurons further suggested that ZPK/DLK and MKK4/MAP2K4-dependent mechanisms underlying axotomy-induced death are motoneuron autonomous. Nevertheless, quantitative analysis of facial motoneurons during embryogenesis revealed that both ZPK/DLK and MKK4/MAP2K4-dependent and -independent mechanisms contribute to developmental elimination of excess motoneurons. In contrast to MKK4/MAP2K4, mice lacking MKK7/MAP2K7, another mitogen-activated protein kinase kinase directly downstream of ZPK/DLK, conditionally in neurons did not have excess facial motoneurons. However, some MKK7/MAP2K7-deficient facial motoneurons were resistant to axotomy-induced death, indicating a synergistic effect of MKK7/MAP2K7 on axotomy-induced death of these facial motoneurons. Together, our study provides compelling evidence for the pivotal roles of the ZPK/DLK and MKK4/MAP2K4-dependent mechanism in axotomy-induced motoneuron death in neonates and also demonstrates that axotomy-induced motoneuron death is not identical to developmental motoneuron death with respect to the involvement of ZPK/DLK, MKK4/MAP2K4 and MKK7/MAP2K7.

Reconstitution of a secondary metabolite biosynthetic pathway in a heterologous fungal host.

Expression of multiple genes involved in a particular metabolic pathway in a heterologous host facilitates the study of fungal secondary metabolite biosynthesis and production of useful compounds. Two plasmids with different selection markers, argB and the pyrithiamine resistance marker, are used to transform Aspergillus oryzae allowing for expression of up to three genes simultaneously.

Interferon regulatory factor 8/interferon consensus sequence binding protein is a critical transcription factor for the physiological phenotype of microglia.

BACKGROUND: Recent fate-mapping studies establish that microglia, the resident mononuclear phagocytes of the CNS, are distinct in origin from the bone marrow-derived myeloid lineage. Interferon regulatory factor 8 (IRF8, also known as interferon consensus sequence binding protein) plays essential roles in development and function of the bone marrow-derived myeloid lineage. However, little is known about its roles in microglia. METHODS: The CNS tissues of IRF8-deficient mice were immunohistochemically analyzed. Pure microglia isolated from wild-type and IRF8-deficient mice were studied in vitro by proliferation, immunocytochemical and phagocytosis assays. Microglial response in vivo was compared between wild-type and IRF8-deficient mice in the cuprizon-induced demyelination model. RESULTS: Our analysis of IRF8-deficient mice revealed that, in contrast to compromised development of IRF8-deficient bone marrow myeloid lineage cells, development and colonization of microglia are not obviously affected by loss of IRF8. However, IRF8-deficient microglia demonstrate several defective phenotypes. In vivo, IRF8-deficient microglia have fewer elaborated processes with reduced expression of IBA1/AIF1 compared with wild-type microglia, suggesting a defective phenotype. IRF8-deficient microglia are significantly less proliferative in mixed glial cultures than wild-type microglia. Unlike IRF8-deficient bone marrow myeloid progenitors, exogenous macrophage colony stimulating factor (colony stimulating factor 1) (M-CSF (CSF1)) restores their proliferation in mixed glial cultures. In addition, IRF8-deficient microglia exhibit an exaggerated growth response to exogenous granulocyte-macrophage colony stimulating factor (colony stimulating factor 2) (GM-CSF (CSF2)) in the presence of other glial cells. IRF8-deficient microglia also demonstrate altered cytokine expressions in response to interferon-gamma and lipopolysaccharide in vitro. Moreover, the maximum phagocytic capacity of IRF8-deficient microglia is reduced, although their engulfment of zymosan particles is not overtly impaired. Defective scavenging activity of IRF8-deficient microglia was further confirmed in vivo in the cuprizone-induced demyelination model in mice. CONCLUSIONS: This study is the first to demonstrate the essential contribution of IRF8-mediated transcription to a broad range of microglial phenotype. Microglia are distinct from the bone marrow myeloid lineage with respect to their dependence on IRF8-mediated transcription.

PEDF is a novel oligodendrogenic morphogen acting on the adult SVZ and corpus callosum.

Pigment epithelium-derived factor (PEDF) is a serine protease inhibitor (serpin) protein with well established neuroprotective and anti-angiogenic properties. Recent studies have also shown that PEDF enhances renewal of adult subventricular zone (SVZ) neural precursors. In neurosphere cultures prepared from the SVZ of adult mice, we found that addition of recombinant PEDF to the medium enhanced expressions of oligodendroglial lineage markers (NG2 and PDGFrα) and transcription factors (Olig1, Olig2, and Sox10). Similarly, continuous PEDF administration into the lateral ventricles of adult glial fibrillary acidic protein:green fluorescent protein (GFAP:GFP) transgenic mice increased the proportions of GFAP:GFP+ and GFAP:GFP- SVZ neural precursors coexpressing oligodendroglial lineage markers and transcription factors. Notably, PEDF infusion also resulted in an induction of doublecortin- and Sox10 double-positive cells in the adult SVZ. Immunoreactive PEDF receptor was detectable in multiple cell types in both adult SVZ and corpus callosum. Furthermore, PEDF intracerebral infusion enhanced survival and maturation of newly born oligodendroglial progenitor cells in the normal corpus callosum, and accelerated oligodendroglial regeneration in lysolecithin-induced corpus callosum demyelinative lesions. Western blot analysis showed a robust upregulation of endogenous PEDF in the corpus callosum upon lysolecithin-induced demyelination. Our results document previously unrecognized oligodendrotrophic effects of recombinant PEDF on the adult SVZ and corpus callosum, demonstrate induction of endogenous CNS PEDF production following demyelination, and make PEDF a strong candidate for pharmacological intervention in demyelinative diseases.

Identification of a key prenyltransferase involved in biosynthesis of the most abundant fungal meroterpenoids derived from 3,5-dimethylorsellinic acid.

Destroying aromaticity: A novel prenyltransferase (Trt2) involved in fungal meroterpenoid biosynthesis was shown to catalyze an unusual aromatic addition reaction onto a fully substituted aromatic ring. The prenylated product serves as a key intermediate in the biosynthesis of the most abundant series of meroterpenoids in fungi.

Structure-activity relationship modeling for predicting interactions with pregnane X receptor by recursive partitioning.

Pregnane X receptor (PXR) is a ligand-activated nuclear factor that upregulates the expression of proteins involved in the detoxification and clearance of xenobiotics, primarily cytochrome P450 3A4 (CYP3A4). Structure-activity relationship (SAR) analysis of PXR agonists is useful for avoiding unwanted pharmacokinetics due to drug-drug interactions. To perform large-scale ligand-based SAR modeling, we systematically collected information on chemical-PXR interactions from the PubMed database by using the text mining system we developed, and merged it with screening data registered in the PubChem BioAssay database and other published data. Curation of the data resulted in 270 human PXR agonists and 248 non-agonists. After the entire data set was divided into training and testing data sets, the training data set comprising 415 data entries (217 positive and 198 negative instances) was analyzed by a recursive partitioning method. The classification tree optimized by a cross-validation pruning algorithm gave an accuracy of 79.0%, and, for the external testing data set, could correctly classify PXR agonists and non-agonists at an accuracy of 70.9%. Descriptors chosen as splitting rules in the classification tree were generally associated with electronic properties of molecules, suggesting they had an important role in the modes of interaction.

Disruption of NMDA receptors in oligodendroglial lineage cells does not alter their susceptibility to experimental autoimmune encephalomyelitis or their normal development.

Pharmacological studies have suggested that oligodendroglial NMDA glutamate receptors (NMDARs) mediate white matter injury in a variety of CNS diseases, including multiple sclerosis (MS). We tested this hypothesis in experimental autoimmune encephalomyelitis (EAE), a model of human MS, by timed conditional disruption of oligodendroglial NR1, an essential subunit of functional NMDARs, using an inducible proteolipid protein (Plp) promoter-driven Cre-loxP recombination system. We found that selective ablation of oligodendroglial NR1 did not alter the clinical severity of EAE elicited in C57BL/6 mice by immunization with myelin oligodendrocyte glycoprotein peptide 35-55 (MOG-peptide), nor were there significant differences between the oligodendroglial NR1 KO and non-KO mice in numbers of axons lost in spinal cord dorsal funiculi or severity of spinal cord demyelination. Similarly, constitutive deletion of NR3A, a modulatory subunit of oligodendroglial NMDARs, did not alter the course of MOG-peptide EAE. Furthermore, conditional and constitutive ablation of NR1 in neonatal oligodendrocyte progenitor cells did not interrupt their normal maturation and differentiation. Collectively, our data suggest that oligodendroglial lineage NMDARs are neither required for timely postnatal development of the oligodendroglial lineage, nor significant participants in the pathophysiology of MOG-peptide EAE.

Amyloid ß1-42 oligomer inhibits myelin sheet formation in vitro.

Accumulating evidence indicates that white matter degeneration contributes to the neural disconnections that underlie Alzheimer's disease pathophysiology. Although this white matter degeneration is partly attributable to axonopathy associated with neuronal degeneration, amyloid ß (Aß) protein-mediated damage to oligodendrocytes could be another mechanism. To test this hypothesis, we studied effects of soluble Aß in oligomeric form on survival and differentiation of cells of the oligodendroglial lineage using highly purified oligodendroglial cultures from rats at different developmental stages. Aß oligomer at 10 µM or higher reduced survival of mature oligodendrocytes, whereas oligodendroglial progenitor cells (OPCs) were relatively resistant to the Aß oligomer-mediated cytotoxicity. Further study revealed that Aß oligomer even at 1 µM accelerated 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) formazan exocytosis in mature oligodendrocytes, and, more significantly, inhibited myelin sheet formation after induction of in vitro differentiation of OPCs. These results imply a novel pathogenetic mechanism underlying Aß oligomer-mediated white matter degeneration, which could impair myelin maintenance and remyelination by adult OPCs, resulting in accumulating damage to myelinating axons thereby contributing to neural disconnections.

Cerebellum-specific and age-dependent expression of an endogenous retrovirus with intact coding potential.

BACKGROUND: Endogenous retroviruses (ERVs), including murine leukemia virus (MuLV) type-ERVs (MuLV-ERVs), are presumed to occupy ~10% of the mouse genome. In this study, following the identification of a full-length MuLV-ERV by in silico survey of the C57BL/6J mouse genome, its distribution in different mouse strains and expression characteristics were investigated. RESULTS: Application of a set of ERV mining protocols identified a MuLV-ERV locus with full coding potential on chromosome 8 (named ERVmch8). It appears that ERVmch8 shares the same genomic locus with a replication-incompetent MuLV-ERV, called Emv2; however, it was not confirmed due to a lack of relevant annotation and Emv2 sequence information. The ERVmch8 sequence was more prevalent in laboratory strains compared to wild-derived strains. Among 16 different tissues of ~12 week-old female C57BL/6J mice, brain homogenate was the only tissue with evident expression of ERVmch8. Further ERVmch8 expression analysis in six different brain compartments and four peripheral neuronal tissues of C57BL/6J mice revealed no significant expression except for the cerebellum in which the ERVmch8 locus' low methylation status was unique compared to the other brain compartments. The ERVmch8 locus was found to be surrounded by genes associated with neuronal development and/or inflammation. Interestingly, cerebellum-specific ERVmch8 expression was age-dependent with almost no expression at 2 weeks and a plateau at 6 weeks. CONCLUSIONS: The ecotropic ERVmch8 locus on the C57BL/6J mouse genome was relatively undermethylated in the cerebellum, and its expression was cerebellum-specific and age-dependent.

ZPK/DLK, a mitogen-activated protein kinase kinase kinase, is a critical mediator of programmed cell death of motoneurons.

Activation of mitogen-activated protein kinase pathways is critically involved in naturally occurring programmed cell death of motoneurons during development, but the upstream mediators remain undetermined. We found that mice deficient in ZPK, also called DLK (ZPK/DLK), an upstream kinase in these pathways, have twice as many spinal motoneurons as do their wild-type littermates. Nuclear HB9/MNX1-positive motoneuron pools were generated similarly in the spinal cord of both ZPK/DLK-deficient and wild-type embryos. Thereafter, however, significantly less apoptotic motoneurons were found in ZPK/DLK-deficient embryos compared with wild-type embryos, resulting in retention of excess numbers of motoneurons after birth. Notably, these excess motoneurons remained viable without atrophic changes in the ZPK/DLK-deficient mice surviving into adulthood. Analysis of the diaphragm and the phrenic nerve revealed that clustering and innervation of neuromuscular junctions were indistinguishable between ZPK/DLK-deficient and wild-type mice, whereas the proximal portion of the phrenic nerve of ZPK/DLK-deficient mice contained significantly more axons than the distal portion. This result supports the hypothesis that some excess ZPK/DLK-deficient motoneurons survived without atrophy despite failure to establish axonal contact with their targets. This study provides compelling evidence for a critical role for ZPK/DLK in naturally occurring programmed cell death of motoneurons and suggests that ZPK/DLK could become a strategic therapeutic target in motor neuron diseases in which aberrant activation of the apoptogenic cascade is involved.

Automated information extraction and structure-activity relationship analysis of cytochrome P450 substrates.

Information on CYP-chemical interactions was comprehensively explored by a text-mining technique, to confirm our previous structure-activity relationship model for CYP substrates (Yamashita et al. J. Chem. Inf. Model. 2008, 48, 364-369). The text-mining technique is based on natural language processing and can extract chemical names and their interaction patterns according to sentence context. After chemicals were automatically extracted and classified into CYP substrates, inhibitors, and inducers, 709 substrates were retrieved from the PubChem database and categorized as 216, 145, 136, 217, 156, and 379 substrates for CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP2E1, and CYP3A4, respectively. Although the previous classification model was developed using data from only 161 compounds, the model classified the substrates found by text-mining analysis with reasonable accuracy. This confirmed the validity of both the multi-objective classification model for CYP substrates and the text-mining procedure.