bluuebunny/crossref_metadata_2025_split huggingface dataset:
Responses of weaned lambs to fear‐eliciting situations: Origin of individual differences
Authors: Viérin Manon , Bouissou Marie‐France 
Published: January 2003

AbstractThe aims of this study were 1) to develop methods of objectively measuring fear in weaned lambs, and 2) to evaluate the effects of age, sex, breed, and rearing conditions on fear reactions. Four hundred forty‐one lambs, aged 3 to 6 months, were submitted to three fear‐eliciting situations (isolation, surprise effect, and human presence). Factor analysis revealed a first factor, interpreted in terms of fear, that accounted for 40% of total variance in the three tests. As in adult sheep, the main signs of fear were inhibition of feeding, long distance from the frightening stimulus, frequent immobilizations, and numerous high‐pitch bleats. Behavior was also influenced by differences in general locomotor activity and exploratory motivation. Fear reactions were influenced by age (3‐ to 4‐month‐old lambs more fearful than 5‐ to 6‐month‐old), sex (females more fearful than males), breed (Romanov more fearful than Ile‐de‐France), and rearing conditions (artificial vs. maternal: almost no influence in males and influence in females depending on age). These results with sheep provide interesting theoretical and practical perspectives to the study of fearfulness. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 131–147, 2003
Classical conditioning in the rat fetus. III. Retention, extinction, and re‐activation of the conditioned response (CR)
Authors: Smotherman William P. 
Published: January 2003

AbstractA single paired presentation of an artificial nipple (conditioned stimulus, CS) and milk (unconditioned stimulus, US) resulted in classical conditioning. When re‐exposed to the artificial nipple CS after conditioning, fetuses showed fewer oral grasp responses compared to control fetuses exposed to the milk (US) and artificial nipple (CS) in an unpaired fashion. The reduction in oral grasping was evident when the test of oral grasping was administered 18 min after conditioning but not 21 to 30 min after conditioning (Experiments 1a and 1b). Experiments 2a and 2b confirmed that nine or more exposures to the CS after conditioning, without a milk infusion, resulted in experimental extinction of the conditioned reduction in oral grasping. One re‐exposure to milk during the period after classical conditioning was sufficient to re‐activate memory for the association between artificial nipple CS and milk US (Experiment 3a). Fetuses exposed to one or two re‐activation treatments that comprised an intraoral infusion of milk showed evidence of the conditioned reduction in oral grasping when tested after a delay sufficient to produce forgetting. Experiment 3b showed that the orosensory properties of milk were sufficient to re‐activate fetal memory for the association between artificial nipple and milk. Experiment 3c indicated that central injection of 10 ng of dynorphin A 1‐13 re‐activated fetal memory for the classically conditioned association. Experiments 3b and 3c suggested that the orosensory properties of milk activated a kappa opioid system in the fetal brain that reduced oral grasping of the artificial nipple during the test for oral grasping. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 181–193, 2003
Derivation of the analytical solution of the fundamental equations for a rectilinearly channeled negative surface discharge
Authors: Iri Masao , Endo Masao , Segawa Shinichi 
Published: January 2003

AbstractThere have been quite a number of theoretical as well as experimental studies concerning discharge phenomena, but the results (or partial results) are complicated mathematically as well as physically.The main subject of the present paper is traced back nearly 20 years when the second author began experiments with an exquisite mechanism he devised [1, 2]. The discharge phenomenon was like the famous Stephan problem, where two different phases of one and the same substance—ice and water—coexist at a free moving boundary between them [3]. But, unlike the Stephan problem, which is linear, the mathematical model of the discharge problem consists of a diffusion‐type nonlinear partial differential equation with initial and boundary conditions. In particular, one of the boundaries is given a fixed condition, whereas the other is moving with a little subtle physical assumption on the speed of the propagation of discharge. Therefore, the nonlinear diffusion equation is difficult to solve by usual methods. Assuming that the applied voltage is constant and that there exists a unique solution, the original initial‐ and boundary‐value problem is reduced to the initial‐value problem of an ordinary differential equation. This latter problem allows us to define a one‐parameter family of novel functions.Details of the derivation of the solution of the fundamental equations and the physical meaning of the propagation condition and the analytical solution for a rectilinearly channeled negative surface discharge are discussed. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 143(1): 8–14, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10112
Design and analysis of a mass spectrometer with superimposed magnetic and rotating electric fields
Authors: Murai Akira , Tahara Norio , Yabunouchi Teruyuki 
Published: January 2003

AbstractWe planned to develop a small and inexpensive measurement device for determination of molecular concentration. The analysis process operates by superimposing a rotating electric field on a magnetic field. When the strength and frequency of the rotating electric field and the mass and speed of the ion are predetermined, the circular radius of the ion's trajectory is fixed. We designed a computer program to simulate ion movement in the electric field and magnetic field.It is possible to calculate the circular movement of the ion in the rotating electric field, and then calculate the circular movement in the superimposed state of the rotating electric field and magnetic field.The magnitude of the mass spectrometer conventionally determines resolution ability. Our definition of resolution is the fraction equal to the distance of separation divided by the distance of the attainment point. The resolution increases gradually at first, and then rises suddenly and dramatically to over 20 times the resolution of that of a spectrometer which does not use a superimposed field. We believe that the theory of ion movement in the rotating electric field and magnetic field could lead to the development of a small and inexpensive analysis machine. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 143(1): 15–26, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10113
Experimental studies of optical Raman amplifiers for 1.3‐µm wavelength band and its application to 20 Gbit/s × 2 WDM transmission
Authors: Yamashita Ikuo , Inoguchi Masaji , Seikai Shigeyuki 
Published: January 2003

AbstractConfigurations of a Raman amplifier suitable for a 1.3‐µm wavelength band are discussed and their properties are experimentally investigated. Pump light with a wavelength of 1.23 µm that is necessary for the Raman amplification in the 1.3‐µm wavelength band is obtained using a 1.06‐µm fiber laser and Raman laser technique. Concerning the Raman laser, wavelength conversion from 1.06 µm to 1.23 µm is effectively achieved using a cavity configuration including fiber Bragg gratings and a dispersion‐shifted fiber. On the other hand, a conventional dispersion compensation fiber which has an essential property of high nonlinearity is applied in order to obtain large gain at 1.3 µm. Net gain of 35 dB and output power of 15 dBm are achieved. To confirm the applicability of the Raman amplifiers to high‐speed optical transmissions, experiments of 20 Gbit/s × 2 WDM repeaterless transmission through a 80‐km conventional single‐mode fiber are carried out. The 1.3‐µm signal should be degraded due to the dispersion caused by the dispersion compensation fiber in the Raman amplifier; However, bit error rate of less than 10 to 12 is obtained at both wavelengths, which is sufficient performance for practical uses. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 143(1): 58–65, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10137
Improving the preparation and implementation of integrated natural resource management plans (INRMPs)
Authors: Boice L. Peter 
Published: January 2003

AbstractThe Sikes Act Improvement Act (SAIA) of 1997 for the first time mandated the military to prepare and
implement integrated natural resource management plans (INRMPs), and to do so in cooperation with the
U.S. Fish and Wildlife Service, appropriate state fish and wildlife agencies, and other stakeholders. The
Department of Defense issued updated guidance for consistently implementing SAIA requirements throughout the
Department on October 10, 2002. This article describes why this new guidance will significantly improve how
military installations prepare, coordinate, and implement their INRMPs. © 2003 Wiley Periodicals Inc.
LPS‐induced expression of a novel chemokine receptor (L‐CCR) in mouse glial cells in vitro and in vivo
Authors: Zuurman Mike W. , Heeroma Joost , Brouwer Nieske , Boddeke Hendrikus W.G.M. , Biber Knut 
Published: January 2003

AbstractThere is increasing evidence that chemokines, specialized regulators of the peripheral immune system, are also involved in the physiology and pathology of the CNS. It is known that glial cells (astrocytes and microglia) express various chemokine receptors like CCR1, ‐3, ‐5, and CXCR4. We have investigated the possible expression of the known CC chemokine receptors (CCR1–8 and D6) in murine glial cells. In addition, we examined possible glial expression of the orphan CC chemokine receptor L‐CCR that has been identified previously in murine macrophages. We report here expression of L‐CCR mRNA in murine astrocytes and microglia. Furthermore, L‐CCR mRNA expression was strongly induced after application of bacterial lipopolysaccharide (LPS), both in vitro and in vivo. Functional studies and binding experiments using biotinylated monocyte chemoattractant protein (MCP)‐1 (CCL2) indicate that CCL2 could be a candidate chemokine ligand for glial L‐CCR. Based on the data presented, it is suggested that L‐CCR is a functional glial chemokine receptor that is important in neuroimmunology. GLIA 41:327–336, 2003. © 2003 Wiley‐Liss, Inc.
Expression of a membrane‐bound form of the ferroxidase ceruloplasmin by leptomeningeal cells
Authors: Mittal Bina , Doroudchi Mohammad M. , Jeong Suh Young , Patel Bharatkumar N. , David Samuel 
Published: January 2003

AbstractCeruloplasmin is a key enzyme involved in detoxifying ferrous iron, which can generate free radicals. The secreted form of ceruloplasmin is produced by the liver and is abundant in serum. We have previously identified a membrane‐bound glycosylphosphatidylinositol (GPI)‐anchored form of ceruloplasmin (GPI‐Cp) that is expressed by astrocytes in the central nervous system (CNS) (Patel and David. 1997. J Biol Chem 272:20185–20190). We now provide direct evidence that rat leptomeningeal cells, which cover the surface of the brain, also express GPI‐Cp. The expression of GPI‐Cp on the surface of these cells increases with postnatal development and is regulated in vitro by cell density, time in culture, and various extracellular matrix molecules. The expression of GPI‐Cp also appears to be regulated differently in astrocytes and leptomeningeal cells in vitro. The abundant expression of GPI‐Cp on the surface of leptomeningeal cells suggests that these cells play a role in antioxidant defense along the surface of the postnatal CNS possibly by detoxifying the cerebrospinal fluid. GLIA 41:337–346, 2003. © 2003 Wiley‐Liss, Inc.
Expression of voltage‐gated Ca2+ channel subtypes in cultured astrocytes
Authors: Latour Isabelle , Hamid Jawed , Beedle Aaron M. , Zamponi Gerald W. , Macvicar Brian A. 
Published: January 2003

AbstractTransient intracellular [Ca2+] increases in astrocytes from influx and/or release from internal stores can release glutamate and thereby modulate synaptic transmission in adjacent neurons. Electrophysiological studies have shown that cultured astrocytes express voltage‐dependent Ca2+ channels but their molecular identities have remained unexplored. We therefore performed RT‐PCR analysis with primers directed to different voltage‐gated Ca2+ channel α1 subunits. In primary cultures of astrocytes, we detected mRNA transcripts for the α1B (N‐type), α1C (L‐type), α1D (L‐type), α1E (R‐type), and α1G (T‐type), but not α1A (P/Q‐type), voltage‐gated Ca2+ channels. We then used antibodies against all of the Ca2+ channel subunits to confirm protein expression, via Western blots, and localization by means of immunocytochemistry. In Western blot analysis, we observed immunoreactive bands corresponding to the appropriate α1 subunit proteins. Western blots showed an expression pattern similar to PCR results in that we detected proteins for the α1B (N‐type), α1C (L‐type), α1D (L‐type), α1E (R‐type), and α1G (T‐type), but not α1A (P/Q‐type). Using immunocytochemistry, we observed Ca2+ channel expression for these subunits in punctate clusters on plasmamembrane of GFAP‐expressing astrocytes. These results confirm that cultured astrocytes express corresponding proteins to several high‐ and low‐threshold Ca2+ channels but not α1A (P/Q‐type). Overall, our data indicate that astrocytes express multiple types of voltage‐gated Ca2+ channels, hinting at a complex regulation of Ca2+ homeostasis in glial cells. GLIA 41:347–353, 2003. © 2003 Wiley‐Liss, Inc.
Morphological plasticity of olfactory ensheathing cells is regulated by cAMP and endothelin‐1
Authors: Vincent Adele J. , West Adrian K. , Chuah Meng Inn 
Published: January 2003

AbstractOlfactory ensheathing cells (ECs) are a promising tool for the repair of injury in the adult central nervous system. However, important aspects of the cell biology of ECs remain unclear, such as whether ECs exist as a single population or as two subpopulations with Schwann cell‐like and astrocyte‐like characteristics. The morphologies of these subpopulations are used as defining characteristics, yet ECs are known to be morphologically plastic. To elucidate this apparent inconsistency, we investigated the morphological plasticity of ECs in culture. We defined purified ECs as immunopositive for both p75 neurotrophin receptor and glial fibrillary acidic protein. In MEM D‐valine modification + 10% dialyzed fetal calf serum, 87%–90% of ECs displayed a flat morphology. In three different serum‐free media (N2 medium, neurobasal medium + B27 supplement, and DMEM/F‐12 medium + G5 supplement), 78%–84% of ECs displayed process‐bearing morphology. Ensheathing cells switched reversibly between these morphologies within a day of the serum conditions being changed. Exposure to 1 nM endothelin‐1 in serum‐free medium prevented the switch from flat to process‐bearing morphology, while 1 mM dibutyryl cAMP accelerated this change. The effects of both agents were completely reversible and similar to that reported for astrocytes. Both flat and process‐bearing ECs were immunopositive for brain‐derived neurotrophic factor, nerve growth factor, neurotrophin‐4, and TrkB but not TrkA. Together, these results suggest that ECs exist as a single morphologically plastic population. GLIA 41:393–403, 2003. © 2003 Wiley‐Liss, Inc.
Quinolinic acid upregulates chemokine production and chemokine receptor expression in astrocytes
Authors: Guillemin Gilles J. , Croitoru‐Lamoury Juliana , Dormont Dominique , Armati Patricia J. , Brew Bruce J. 
Published: January 2003

AbstractWithin the brain, quinolinic acid (QUIN) is an important neurotoxin, especially in AIDS dementia complex (ADC). Its production by monocytic lineage cells is increased in the context of inflammation. However, it is not known whether QUIN promotes inflammation. Astrocytes are important in immunoregulation within the brain and so we chose to examine the effects of QUIN on the astrocyte. Using purified primary human fetal astrocyte cultures, we determined chemokine production using ELISA assays and RT‐PCR and chemokine receptor expression using immunocytochemistry and RT‐PCR with QUIN in comparison to TNFα, IL‐1β, and IFNγ. We found that QUIN induces astrocytes to produce large quantities of MCP‐1 (CCL2) and lesser amounts of RANTES (CCL5) and IL‐8 (CXCL8). QUIN also increases SDF‐1α (CXCL12), HuMIG (CXCL9), and fractalkine (CX3CL1) mRNA expression. Moreover, QUIN leads to upregulation of the chemokine receptor expression of CXCR4, CCR5, and CCR3 in human fetal astrocytes. Most of these effects were comparable to those induced by TNFα, IL‐1β, and IFNγ. The present work represents the first evidence that QUIN induces chemokine and chemokine receptor expression in astrocytes and is at least as potent as classical mediators such as inflammatory cytokines. These results suggest that QUIN may be critical in the amplification of brain inflammation, particularly in ADC. GLIA 41:371–381, 2003. © 2003 Wiley‐Liss, Inc.
Expression of chemokines and their receptors in human and simian astrocytes: Evidence for a central role of TNFα and IFNγ in CXCR4 and CCR5 modulation
Authors: Croitoru‐Lamoury Juliana , Guillemin Gilles J. , Boussin François D. , Mognetti Barbara , Gigout Laure I. , Chéret Arnaud , Vaslin Bruno , Le Grand Roger , Brew Bruce J. , Dormont Dominique 
Published: January 2003

AbstractChemokines are key mediators of the selective migration of leukocytes that occurs in neurodegenerative diseases and related inflammatory processes. Astrocytes, the most abundant cell type in the CNS, have an active role in brain inflammation. To ascertain the role of astrocytes during neuropathological processes, we have investigated in two models of primary cells (human fetal and simian adult astrocytes) the repertoire of chemokines and their receptors expressed in response to inflammatory stimuli. We demonstrated that, in the absence of any stimulation, human fetal and simian adult astrocytes express mRNA for receptors APJ, BOB/GPR15, Bonzo/CXCR6, CCR2, CCR3, CCR5, CCR8, ChemR23, CXCR3/GPR9, CXCR4, GPR1, and V28/CX3CR1. Moreover, TNFα and IL‐1β significantly increase BOB/GPR15, CCR2, and V28/CX3CR1 mRNA levels in both models. Furthermore, TNFα and IFNγ act synergistically to induce expression of the major coreceptors for HIV infection, CXCR4 and CCR5, at both the mRNA and protein levels in human and simian astrocytes, whereas CCR3 expression was not affected by cytokine treatment. Finally, TNFα/IFNγ was the most significant cytokine combination in leading to a pronounced upregulation in a comparable, time‐dependent manner of the production of chemokines IP‐10/CXCL10, RANTES/CCL5, MIG/CXCL9, MCP‐1/CCL2, and IL‐8/CXCL8. In summary, these data suggest that astrocytes serve as an important source of chemokines under the dependence of a complex cytokine regulation, and TNFα and IFNγ are important modulators of chemokines and chemokine receptor expression in human as well as simian astrocytes. Finally, with the conditions we used, there was no difference between species or age of tissue. GLIA 41:354–370, 2003. © 2003 Wiley‐Liss, Inc.
Astrocytes in culture express fibrillar collagen
Authors: Heck Nicolas , Garwood Jeremy , Schütte Katrin , Fawcett James , Faissner Andreas 
Published: January 2003

AbstractThe use of monoclonal antibodies has led to much progress in the characterization of extracellular matrix components of the CNS. F1C3 is a monoclonal antibody raised against the astrocytic cell line, Neu7. Analysis by immunoprecipitation and Western blots of the F1C3 antigen in Neu7 cell lysates and conditioned medium reveals a recognition of several protein bands around 140–230 kD. Internal peptide sequence data from these bands indicate that they are highly homologous to fibrillar collagens, and the F1C3 antigen is specifically digested by the collagenase I protease. Other glial cell lines show F1C3 antigen expression including A7, C6, and U373. Cultures of neonatal primary astrocytes also express F1C3 antigen, and Western blot analysis of rat brain extracts from different ages and parts of the brain confirm an in vivo expression of F1C3 protein. The significance of the expression of fibrillar collagen‐like proteins by astrocytes is discussed together with its possible implication during developmental processes and in the context of CNS lesions and regeneration. GLIA 41:382–392, 2003. © 2003 Wiley‐Liss, Inc.
Surface carbonic anhydrase activity on astrocytes and neurons facilitates lactate transport
Authors: Svichar Nataliya , Chesler Mitchell 
Published: January 2003

AbstractA number of studies have provided physiological evidence for extracellular carbonic anhydrase (CA) in brain. Association of extracellular CA with glia has been limited to functional studies of gliotic slices and retinal Muller cells. While astrocytes contain intracellular CA, there has been no direct evidence for surface CA on these cells. In fact, some morphological studies suggest that the extracellular CA in brain parenchyma resides on neurons, not glia. There has been no functional demonstration of extracellular CA activity on CNS neurons, however. Here we capitalized on the H+ dependence of inward lactate transport to reveal functional extracellular CA activity on cultured astrocytes and acutely isolated hippocampal pyramidal neurons. Exposure to 20 mM L‐lactate produced a rapid acidification of astrocytes that was reversibly blocked by 10 μM benzolamide. The lactate‐induced acidification (LIA) was also blocked by a dextran‐conjugated CA inhibitor. In CO2/HCO3−‐free, HEPES‐buffered media, the LIA was largely unaffected. Acutely dissociated hippocampal pyramidal neurons underwent a similar LIA that was reversibly blocked by benzolamide. Surface CA is likely to facilitate lactate transport by enabling rapid replenishment (i.e., buffering) of surface H+ required for inward lactate‐H+ cotransport. These results demonstrate functional surface CA for the first time on individual mammalian astrocytes and neurons and suggest that this enzyme may play a role in the utilization of monocarboxylate substrates such as lactate and pyruvate by the brain. GLIA 41:415–419, 2003. © 2003 Wiley‐Liss, Inc.
Postnatal development of GFAP in mouse visual cortex is not affected by light deprivation
Authors: Corvetti Luigi , Capsoni Simona , Cattaneo Antonino , Domenici Luciano 
Published: January 2003

AbstractMammalian visual cortex is immature at birth and develops gradually during defined postnatal temporal windows. In the present work, we studied the maturation of astrocytes in developing mouse visual cortex (VC). The cellular distribution and the level of glial fibrillary acidic protein (GFAP) were analyzed by immunohistochemistry and Western blotting. Experiments were performed at different postnatal ages: postnatal day 12 (P12), before eye opening; P24, corresponding roughly to the peak of the critical period for monocular deprivation, and P60, after the end of the critical period. At P12, GFAP immunoreactivity (IR) was distributed throughout all cortical layers. At P24, there was a prominent localization of GFAP IR in layers I, II, and VI, while cortical layers III, IV, and V contained no longer GFAP IR cells. No differences were found in GFAP IR between P24 and P60. Western blot analysis revealed a reduction of GFAP expression in the VC at P24 with respect to P12 and no significant difference between P60 and P24. These results show that GFAP expression is modulated during early postnatal development. To know whether visual experience influences the maturation pattern of GFAP expression, mice were dark‐reared from P12 to P24. Dark rearing did not change the distribution and the expression of GFAP. Our results indicate that maturation of GFAP expression occurs early in postnatal development in mouse VC. In addition, we showed that GFAP development is not affected by visual deprivation. GLIA 41:404–414, 2003. © 2003 Wiley‐Liss, Inc.