bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Allantoic Core Domain: New insights into development of the murine allantois and its relation to the primitive streak
Authors: Downs Karen M. , Inman Kimberly E. , Jin Dexter X. , Enders Allen C. 
Published: February 2009

AbstractThe whereabouts and properties of the posterior end of the primitive streak have not been identified in any species. In the mouse, the streak's posterior terminus is assumed to be confined to the embryonic compartment, and to give rise to the allantois, which links the embryo to its mother during pregnancy. In this study, we have refined our understanding of the biology of the murine posterior primitive streak and its relation to the allantois. Through a combination of immunostaining and morphology, we demonstrate that the primitive streak spans the posterior extraembryonic and embryonic regions at the onset of the neural plate stage (∼7.0 days postcoitum, dpc). Several hours later, the allantoic bud emerges from the extraembryonic component of the primitive streak (XPS). Then, possibly in collaboration with overlying allantois‐associated extraembryonic visceral endoderm, the XPS establishes a germinal center within the allantois, named here the Allantoic Core Domain (ACD). Microsurgical removal of the ACD beyond headfold (HF) stages resulted in the formation of allantoic regenerates that lacked the ACD and failed to elongate; nevertheless, vasculogenesis and vascular patterning proceeded. In situ and transplantation fate mapping demonstrated that, from HF stages onward, the ACD's progenitor pool contributed to the allantois exclusive of the proximal flanks. By contrast, the posterior intraembryonic primitive streak (IPS) provided the flanks. Grafting the ACD into TC/TC hosts, whose allantoises are significantly foreshortened, restored allantoic elongation. These results revealed that the ACD is essential for allantoic elongation, but the cues required for vascularization lie outside of it. On the basis of these and previous findings, we conclude that the posterior primitive streak of the mouse conceptus is far more complex than was previously believed. Our results provide new directives for addressing the origin and development of the umbilical cord, and establish a novel paradigm for investigating the fetal/placental relationship. Developmental Dynamics 238:532–553, 2009. © 2009 Wiley‐Liss, Inc.
Hoxb13 regulatory elements mediate transgene expression during prostate organogenesis and carcinogenesis
Authors: McMullin Ryan P. , Mutton Laura N. , Bieberich Charles J. 
Published: February 2009

AbstractThe prostate requires androgens for development and homeostasis. Prostate cancer shares this dependence, however progression to androgen‐independence is common after androgen deprivation. There is considerable interest in achieving therapeutic gene expression after androgen ablation using prostate‐specific promoters. Paradoxically, known prostate‐restricted cis‐regulatory elements are androgen dependent. Hoxb13 expression is restricted in adults to the prostate and colon, and robust Hoxb13 expression persists after castration. To locate regulatory elements conferring this expression pattern, a lacZ reporter was inserted into the Hoxb13 locus on a mouse genomic bacterial artificial chromosome. In transgenic mice, this construct recapitulated the Hoxb13 expression pattern, including expression after castration. Reporter gene activity was maintained during carcinogenesis in a prostate cancer model. Hoxb13 cis‐regulatory elements provide a powerful tool to achieve androgen‐independent transgene expression in the prostate and distal colon‐specific expression in the gastrointestinal tract. These data establish a framework for high‐resolution analyses of factors regulating Hoxb13. Developmental Dynamics 238:664–672, 2009. © 2009 Wiley‐Liss, Inc.
Aph‐1 is required to regulate Presenilin‐mediated γ‐secretase activity and cell survival in Drosophila wing development
Authors: Cooper Emilie , Deng Wu‐Min , Chung Hui‐Min 
Published: February 2009

AbstractAph‐1 is a multipass transmembrane protein and an essential component of the Presenilin (Psn)‐mediated γ‐secretase complex. During protease assembly, Aph‐1 stabilizes the newly synthesized Psn holoprotein to facilitate generation of the active form of Psn, which is a Psn‐NTF/Psn‐CTF heterodimer produced through a Presenilinase‐initiated endoproteolytic cleavage of the Psn holoprotein. Although it is clear that loss of Aph‐1 activity leads to failure of Psn heterodimer formation, little is understood about whether Aph‐1 plays a role in regulating γ‐secretase activity in addition to assisting Psn maturation. Using various modified Psn forms that do not require endoproteolysis or have a large deletion of the cytosolic loop, we show that in Drosophila Aph‐1 is still required for γ‐secretase activity independent of its role in promoting Psn endoproteolysis. In addition, our results indicate that Aph‐1 is required to promote cell survival in the wing imaginal disc; aph‐1 mutant cells are lost either through cell death or because of a defect in cell proliferation. This function of Aph‐1 is independent of its role in regulating γ‐secretase activity, but possibly involves downregulating the activity of uncleaved Psn holoprotein. genesis 47:169–174, 2009. © 2009 Wiley‐Liss, Inc.
Decomposition and reconstruction of signal in real‐time spectral analysis
Authors: Nakatsuji Hideto , Omatu Sigeru 
Published: February 2009

AbstractIn recent years, wavelet transform which gives expression in the time–frequency domain has been adopted for a nonstationary process. The authors have proposed a new spectral analytical method in the time–frequency domain. In the conventional spectral analytical methods, the decomposition and the reconstruction of signals have been obtained analytically. The proposed method consists of two approaches. We call these approaches Approach 1 and Approach 2. In this paper, we show the decomposition and reconstruction of signals based on Approach 1. First, we show that the signal is decomposed to the signal elements. They are called the decomposition waves, and all of these decomposed waves are added to obtain the reconstructed wave. Next, we show the magnitude characteristic and the phase characteristic between the original signal and the reconstructed wave. Then the conditions between the signal and the reconstructed wave are derived to realize a sufficiently approximated wave. By a numeric calculation example, we show the approximation ability by the proposed method. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 91(11): 37–45, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10182
Classification of semiconductor defects using a small number of training data and qualitative knowledge
Authors: Shimomura Shohei , Igarashi Hajime , Hiroi Takashi , Hosoya Naoki , Nakagawa Yasuo 
Published: February 2009

AbstractIn semiconductor wafer manufacturing processes, defect candidates are usually extracted by an inspection system. The defect candidates are composed of true defects such as open circuits, contaminants, and bridges, as well as nondefect patterns, called nuisances, which predominate over true defects. The goal of this study is to classify the defect candidates as the various true defects and nuisances by using a small number of training data obtained by SEM inspection. It is shown that the accuracy of clustering is considerably improved by use of qualitative knowledge about the defects, given a priori by inspectors, in the clustering processes. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 91(11): 46–54, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10183
Development of an identification system for location of free metallic particles in GIS based on analysis of Lamb waves
Authors: Kozako Masahiro , Ohtsuka Shinya , Kaneko Shuhei , Okabe Shigemitsu , Hikita Masayuki 
Published: February 2009

AbstractWe investigated propagation properties of Lamb waves in a gas‐insulated switchgear (GIS) tank to diagnose insulation performance of GIS. The acoustic signals excited by a free metallic particle colliding with the tank sheath were measured using AE sensors. The wavelet transform was applied to decompose the wave data into its time–frequency components. As a result, difference of propagation properties of Lamb waves is clearly seen with different sizes of GIS tank. Based on the characteristics of Lamb waves, algorithms for location identification of a free metallic particle were examined in model GIS using two AE sensors. Herein, we propose a new system for location identification of a free metallic particle in GIS. Moreover, it is verified that the new identification system is suitable as a diagnostic technique for GIS. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 167(3): 28–35, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20676
The Magnetotransport Properties and a Neutron Diffraction Study of Sr2–xNdxFeMoO6 Double Perovskites
Authors: Retuerto María , Martínez‐Lope María Jesús , García‐Hernández Mar , Alonso José Antonio 
Published: February 2009

AbstractNew electron‐doped derivatives of the Sr2FeMoO6 double perovskite have been studied. We report on the synthesis of the Sr2–xNdxFeMoO6 (x = 0, 0.2, 0.4 and 0.6) perovskite series by a wet chemistry procedure and its characterization. The evolution of the crystal and magnetic structure has been analyzed from neutron powder diffraction data. The partial replacement of Sr2+ cations by higher valence Nd3+ cations induces an injection of electrons into the Fe/Mo sublattice. A bond‐valence study demonstrates that this electron‐injection preferentially affects the Mo orbitals. This substitution leads to a distortion of the structure from tetragonal (I4/m) to monoclinic (P21/n) at room temperature for x ≥ 0.4 and an increase of the disorder between Fe and Mo cations. This effect has severe consequences for the magnetic properties, notably a reduction of the saturation magnetization and a non‐monotonic behavior of the Curie temperature. Magnetotransport measurements show a significant increment of the magnetoresistance at low temperature for high values of x. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Hypercoordinate Silicon Complexes of (O,N,N′ vs. O,N,O′) Schiff Base Type N‐(2‐Carbamidophenyl)imines: Examples of Exclusively O‐Silylated Carbamides
Authors: Kämpfe Alexander , Kroke Edwin , Wagler Jörg 
Published: February 2009

AbstractTridentate salphen‐type O,N,N′ chelators, upon acylation of the NH2 group, are capable of engaging an O,N,O′ coordination mode in addition to their inherent O,N,N′ donor character. In six‐coordinate silicon complexes of the type SiL2 [L = N‐(2‐carbamidophenyl)imine], these ligands were found to exclusively form SiN2O4 coordination spheres by engaging their tridentate O,N,O′ donor capability. Selected ligands L were also shown to preferably engage the O,N,O′ coordination mode when incorporated in five‐ and four‐coordinate silicon compounds of the type LSiPhX (X = Cl, F) and LSiPh2, respectively. The coordination modes of the herein presented six‐, five‐, and four‐coordinate silicon compounds represent the first examples of X‐ray structurally confirmed O‐silylated carbamides, which hence adopt structural features of C‐siloxyimines.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
A New Titanium Alkoxide–Thiolate Complex as a Versatile Heterofunctional Metalloligand
Authors: Fandos Rosa , Otero Antonio , Rodríguez Ana , Terreros Pilar , Aullón Gabriel , Álvarez Santiago 
Published: February 2009

AbstractThe titanium complex [TiCp*(OSBz)(OBzSH)] (1) has been synthesized by reaction of [TiCp*(Me)3] (Cp* = η5‐C5Me5) with 2‐mercaptobenzyl alcohol (H2OSBz). The reaction of complex 1 with H2O gives the dinuclear oxo‐bridged complex [{TiCp*(OSBz)}2(μ‐O)] (2). Complex 1 reacts with [M(μ‐OH)(cod)]2 (M = Rh, Ir) to yield the early–late heterobimetallic complexes [TiCp*(OSBz)2M(cod)] {M = Rh (3); Ir (4)}. Carbon monoxide easily replaces the cod ligand in 3 and 4, which leads to the corresponding dicarbonyl derivatives [TiCp*(OSBz)2M(CO)2] {M = Rh (5); Ir (6)}. Compound 5 reacts with PPh3 to yield the monocarbonyl complex [TiCp*(OSBz)2Rh(CO)(PPh3)] (7). The molecular structures of complexes 2 and 5 have been established by single‐crystal X‐ray diffraction studies. The structure of complex 1 and its coordination mode toward a rhodium moiety have been ascertained by means of calculations based on density functional theory. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Continuous Flow Hydrogenation of Functionalized Pyridines
Authors: Irfan Muhammed , Petricci Elena , Glasnov Toma N. , Taddei Maurizio , Kappe C. Oliver 
Published: February 2009

AbstractThe heterogeneous hydrogenation of substituted pyridines has been accomplished by employing a continuous flow hydrogenation device that incorporates in situ hydrogen generation by electrolysis of H2O and pre‐packed catalyst cartridges. In general, the hydrogenation reactions proceeded smoothly regardless of the supported precious metal catalyst (Pd/C, Pt/C, or Rh/C). By using 30–80 bar of hydrogen pressure at 60–80 °C full conversion was typically achieved in all cases at a flow rate of 0.5 mL min–1, providing the corresponding piperidines in high yields. For disubstituted pyridines, variations in stereoselectivity were observed depending on both the metal catalyst and the temperature/pressure of the hydrogenation reaction. For ethyl nicotinate the selectivity between partial and full hydrogenation could be tuned depending on the hydrogen pressure, solvent, and the choice of supported metal catalyst. Changing the hydrogen source from H2O to D2O allowed the preparation of deuteriated derivatives. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Cyclohexane‐1,2‐diamines: Efficient Catalysts for the Enantioselective Conjugate Addition of Ketones to Nitro Olefins
Authors: Rasappan Ramesh , Reiser Oliver 
Published: February 2009

AbstractSimple monosulfonated cyclohexane‐1,2‐diamines are highly enantioselective organocatalysts for the conjugate addition of ketones to nitro olefins. By focusing on aromatic ketones as the most challenging substrates, selectivities of up to 98 % ee can be achieved for the title reaction. Moreover, a three‐component process between the primary amine catalyst, the nitroalkene, and the ketone, which results in the irreversible formation of pyrrols has been recognized as a reaction pathway for catalyst deactivation.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
A model for the 3D kinematic interaction analysis of pile groups in layered soils
Authors: Dezi Francesca , Carbonari Sandro , Leoni Graziano 
Published: February 2009

AbstractThe paper presents a numerical model for the analysis of the soil–structure kinematic interaction of single piles and pile groups embedded in layered soil deposits during seismic actions. A finite element model is considered for the pile group and the soil is assumed to be a Winkler‐type medium. The pile–soil–pile interaction and the radiation problem are accounted for by means of elastodynamic Green's functions. Condensation of the problem permits a consistent and straightforward derivation of both the impedance functions and the foundation input motion, which are necessary to perform the inertial soil–structure interaction analyses. The model proposed allows calculating the internal forces induced by soil–pile and pile‐to‐pile interactions. Comparisons with data available in literature are made to study the convergence and validate the model. An application to a realistic pile foundation is given to demonstrate the potential of the model to catch the dynamic behaviour of the soil–foundation system and the stress resultants in each pile. Copyright © 2009 John Wiley & Sons, Ltd.
Human bone marrow‐derived mesenchymal stem cells induce Th2‐polarized immune response and promote endogenous repair in animal models of multiple sclerosis
Authors: Bai Lianhua , Lennon Donald P. , Eaton Valerie , Maier Kari , Caplan Arnold I. , Miller Stephen D. , Miller Robert H. 
Published: February 2009

AbstractCell‐based therapies are attractive approaches to promote myelin repair. Recent studies demonstrated a reduction in disease burden in mice with experimental allergic encephalomyelitis (EAE) treated with mouse mesenchymal stem cells (MSCs). Here, we demonstrated human bone marrow‐derived MSCs (BM‐hMSCs) promote functional recovery in both chronic and relapsing‐remitting models of mouse EAE, traced their migration into the injured CNS and assayed their ability to modulate disease progression and the host immune response. Injected BM‐hMSCs accumulated in the CNS, reduced the extent of damage and increased oligodendrocyte lineage cells in lesion areas. The increase in oligodendrocytes in lesions may reflect BM‐hMSC‐induced changes in neural fate determination, since neurospheres from treated animals gave rise to more oligodendrocytes and less astrocytes than nontreated neurospheres. Host immune responses were also influenced by BM‐hMSCs. Inflammatory T‐cells including interferon gamma producing Th1 cells and IL‐17 producing Th17 inflammatory cells and their associated cytokines were reduced along with concomitant increases in IL‐4 producing Th2 cells and anti‐inflammatory cytokines. Together, these data suggest that the BM‐hMSCs represent a viable option for therapeutic approaches. © 2009 Wiley‐Liss, Inc.
Microarray analyses reveal regional astrocyte heterogeneity with implications for neurofibromatosis type 1 (NF1)‐regulated glial proliferation
Authors: Yeh Tu‐Hsueh , Lee Da Yong , Gianino Scott M. , Gutmann David H. 
Published: February 2009

AbstractNumerous studies have suggested that astrocytes in the central nervous system (CNS) exhibit molecular and functional heterogeneity. In this regard, astroglia from different CNS locations express distinct immune system, and neurotransmitter proteins, have varying levels of gap junction coupling and respond differently to injury. However, the relevance of these differences to human disease is unclear. As brain tumors in children arise in specific CNS locations, we hypothesized that regional astroglial cell heterogeneity might partly underlie the propensity for gliomas to arise in these areas. In this study, we performed high‐density RNA microarray profiling on astrocytes from postnatal day 1 optic nerve, cerebellum, brainstem, and neocortex. We showed that astroglia from each region are molecularly distinct, and we were able to develop gene expression patterns that distinguish astroglia, but not neural stem cells, from these different brain regions. We next used these microarray data to determine whether brain tumor suppressor genes were differentially expressed in these distinct populations of astroglia. Interestingly, neurofibromatosis type 1 (NF1) gene expression was decreased at both the RNA and protein levels in neocortical astroglia relative to astroglia from the other brain regions. To determine the functional significance of this finding, we found increased astroglial cell proliferation in optic nerve, brainstem, and cerebellum, but not neocortex, following Nf1 inactivation in vitro and in vivo. These findings provide molecular evidence for CNS astroglial cell heterogeneity, and suggest that differences in tumor suppressor gene expression might contribute to the regional localization of human brain tumors. © 2009 Wiley‐Liss, Inc.
Dual regulation of Ca2+‐dependent glutamate release from astrocytes: Vesicular glutamate transporters and cytosolic glutamate levels
Authors: Ni Yingchun , Parpura Vladimir 
Published: February 2009

AbstractVesicular glutamate transporters (VGLUTs) are responsible for vesicular glutamate storage and exocytotic glutamate release in neurons and astrocytes. Here, we selectively and efficiently overexpressed individual VGLUT proteins (VGLUT1, 2, or 3) in solitary astrocytes and studied their effects on mechanical stimulation‐induced Ca2+‐dependent glutamate release. Neither VGLUT1 nor VGLUT2 overexpression changed the amount of glutamate release, whereas overexpression of VGLUT3 significantly enhanced Ca2+‐dependent glutamate release from astrocytes. None of the VGLUT overexpression affected mechanically induced intracellular Ca2+ increase. Inhibition of glutamine synthetase activity by L‐methionine sulfoximine in astrocytes, which leads to increased cytosolic glutamate concentration, greatly increased their mechanically induced Ca2+‐dependent glutamate release, without affecting intracellular Ca2+ dynamics. Taken together, these data indicate that both VGLUT3 and the cytosolic concentration of glutamate are key limiting factors in regulating the Ca2+‐dependent release of glutamate from astrocytes. © 2009 Wiley‐Liss, Inc.
Imaging glioma cell invasion in vivo reveals mechanisms of dissemination and peritumoral angiogenesis
Authors: Winkler Frank , Kienast Yvonne , Fuhrmann Martin , Von Baumgarten Louisa , Burgold Steffen , Mitteregger Gerda , Kretzschmar Hans , Herms Jochen 
Published: February 2009

AbstractInfiltration of cancer cells into normal tissue is a hallmark of malignant gliomas and compromises treatment options. A lack of appropriate models limits the study of this invasion in vivo, which makes it difficult to fully understand its anatomy and the role of dynamic interactions with structures of the normal brain. We developed a novel methodology by utilizing multiphoton laser scanning microscopy (MPLSM) to image the movement of glioma cells deep within the normal brain of live mice in real time. This allowed us to track the invasion of individual RFP‐expressing GL261 cells in relation to perfused vasculature or GFP‐labeled endothelial cells repetitively over days, up to a depth of 0.5 mm. Glioma cells moved faster and more efficiently when the abluminal site of a blood vessel was utilized for invasion. Cells that invaded perivascularly were frequently found next to (a) multiple capillary structures where microvessels run parallel to each other, (b) capillary loops or glomeruloid‐like bodies, and (c) dilated capillaries. Dynamic MPLSM for more than 48 h revealed that single invasive glioma cells induced intussusceptive microvascular growth and capillary loop formation, specifically at the microvascular site with which they had contact. As the main tumor grew by cooption of existing brain vessels, these peritumoral vascular changes may create a beneficial environment for glioma growth. In conclusion, our study revealed new mechanisms of peritumoral angiogenesis and invasion in gliomas, providing an explanation for their interdependence. © 2009 Wiley‐Liss, Inc.