CCN3 and bone marrow cells

CCN3 expression was observed in a broad variety of tissues from the early stage of development. However, a kind of loss of function in mice (CCN3 del VWC domain -/-) demonstrated mild abnormality, which indicates that CCN3 may not be critical for the normal embryogenesis as a single gene. The importance of CCN3 in bone marrow environment becomes to be recognized by the studies of hematopoietic stem cells and Chronic Myeloid Leukemia cells. CCN3 expression in bone marrow has been denied by several investigations, but we found CCN3 positive stromal and hematopoietic cells at bone extremities with a new antibody although they are a very few populations. We investigated the expression pattern of CCN3 in the cultured bone marrow derived mesenchymal stem cells and found its preference for osteogenic differentiation. From the analyses of in vitro experiment using an osteogenic mesenchymal stem cell line, Kusa-A1, we found that CCN3 downregulates osteogenesis by two different pathways; suppression of BMP and stimulation of Notch. Secreted CCN3 from Kusa cells inhibited the differentiation of osteoblasts in separate culture, which indicates the paracrine manner of CCN3 activity. CCN3 may also affect the extracellular environment of the niche for hematopoietic stem cells

CXCL12-Mediated Guidance of Migrating Embryonic Stem Cell-Derived Neural Progenitors Transplanted into the Hippocampus

Stem cell therapies for neurodegenerative disorders require accurate delivery of the transplanted cells to the sites of damage. Numerous studies have established that fluid injections to the hippocampus can induce lesions in the dentate gyrus (DG) that lead to cell death within the upper blade. Using a mouse model of temporal lobe epilepsy, we previously observed that embryonic stem cell-derived neural progenitors (ESNPs) survive and differentiate within the granule cell layer after stereotaxic delivery to the DG, replacing the endogenous cells of the upper blade. To investigate the mechanisms for ESNP migration and repair in the DG, we examined the role of the chemokine CXCL12 in mice subjected to kainic acid-induced seizures. We now show that ESNPs transplanted into the DG show extensive migration through the upper blade, along the septotemporal axis of the hippocampus. Seizures upregulate CXCL12 and infusion of the CXCR4 antagonist AMD3100 by osmotic minipump attenuated ESNP migration. We also demonstrate that seizures promote the differentiation of transplanted ESNPs toward neuronal rather than astrocyte fates. These findings suggest that ESNPs transplanted into the adult rodent hippocampus migrate in response to cytokine-mediated signals

Solidification Modeling of a Spiral Casting to Determine Material Fluidity by DISTRIBUTION OF THIS DOCUMENT IS UNLIMITED Solidification Modeling of a Spiral Casting to Determine Material Fluidity

Abstract In casting, fluidity is the measure of the distance a metal can flow in a channel before being stopped by solidification. During mold filling, the metal loses heat to the surrounding mold, thereby cooling and becoming more viscous until the leading portion solidifies and no further flow is possible. A coupled heat-transfer and fluid-flow modeling of a spiral, involving the use of thermophysical properties to determine material fluidity, has been conducted. Fluidity experiments were performed by Caterpillar; several spiral test castings were poured. Simulations of these experiments utilized the Casting Process Simulator (CaPS) software developed at Argonne National Laboratory. Two types of spiral geometries with different assumptions were considered: (1) a two-dimensional laterally stretched spiral and (2) a three-dimensional lateral spiral. The computed extent of mold filling is in good agreement with the experimental results. Time required by the metal/gas interface to attain specific positions in the spiral arm also compares favorably with the experimental results. 'The influence of process variables, especially pour time, is discussed. The CaPS software has been used as a computational tool to investigate the validity of the dimensionality assumptions and to evaluate the ability of CaPS to model fluidity adequately. iii Content

Argonne National Laboratory Reports

In casting, fluidity is the measure of the distance a metal can flow in a channel before being stopped by solidification. During mold filling, the metal loses heat to the surrounding mold, thereby cooling and becoming more viscous until the leading portion solidifies and no further flow is possible. A coupled heat-transfer and fluid-flow modeling of a spiral, involving the use of thermophysical properties to determine material fluidity, has been conducted. Simulations of these experiments utilized the Casting Process Simulator (CaPS) software developed at Argonne National Laboratory. Two types of spiral geometries with different assumptions were considered: (1) a two-dimensional laterally stretched spiral and (2) a three-dimensional lateral spiral. The computer extent of mold filling is in good agreement with the experimental results. Time required by the metal/gas interface to attain specific positions in the spiral arm also compares favorably with the experimental results. The influence of process variables, especially pour time, is discussed. The CaPS software has been used as a computational tool to investigate the validity of the dimensionality assumptions and to evaluate the ability of CaPS to model fluidity adequately

Capital account regulation in Iceland: does anybody know what is going to happen?

This article analyzes the capital account regulation (CAR) applied in Iceland after the banking crash of October 2008, focusing on the determinants behind the implementation of this policy tool, its effects on economic performance, and its possible costs for the Icelandic economy. The previous literature on the topic is useful for these purposes but it does not provide an adequate framework for analyzing the Icelandic experience because Iceland is a very particular case within the group of countries that have historically resorted to CAR. Our main conclusions are that capital account regulation has been essential in stabilizing the currency after the banking crash, providing space for expansionary monetary policy, and keeping public debt yields low. Even though great uncertainty still surrounds the long-term prospects of the Icelandic economy, CAR implementation has been a step toward a promising future economic scenario.Depto. de Economía Aplicada, Estructura e HistoriaFac. de Ciencias Económicas y EmpresarialesTRUEpu