bluuebunny/crossref_metadata_2025_split huggingface dataset:
Re‐evaluation of phencyclidine low‐affinity or “non‐NMDA” binding sites
Authors: Hirbec Hélène , Mausset Anne‐Laure , Kamenka Jean Marc , Privat Alain , Vignon Jacques 
Published: August 2002

AbstractTCP and its derivative gacyclidine (± GK11) are high‐affinity non‐competitive antagonists of N‐methyl‐D‐aspartate (NMDA) receptors (NMDARs) and as such exhibit significant neuroprotective properties. These compounds also bind with a low affinity to binding sites whose pharmacological profiles are different from that of NMDARs. With the intention to develop new strategies of neuroprotection, we found it mandatory to investigate whether 1‐[1‐(2‐thienyl)cyclohexyl]piperidine (TCP) and gacyclidine low‐affinity sites are similar. The effects of several drugs selective for either NMDARs or the [3H]TCP low‐affinity site (or PCP3 site) on (+), (−)[3H]GK11 and [3H]TCP specific binding were investigated. Competition experiments on cerebellum homogenates revealed substantial differences between the pharmacological profiles of the PCP3 site and that of gacyclidine's enantiomers low‐affinity sites. Under experimental conditions preventing the interaction of the radioligands with NMDARs, the autoradiographic study showed, however, that the distributions of both [3H]TCP and (−)[3H]GK11 specific binding were similar. The specific labelling was low and uniform in telencephalic structures, whereas in the cerebellum it was higher in the molecular than in the granular layer. Finally, the analysis of competition experiments performed on tissues slices demonstrated that PCP3 selective ligands were unable to prevent [3H]TCP or (−)[3H]GK11 binding to “non‐NMDA” binding sites. As a whole, our data suggest that: (1) the different pharmacological profiles of [3H]TCP and [3H]gacyclidine enantiomers on low‐affinity sites are due to their selectivity for specific NMDARs subpopulations; (2) the pharmacological isolation of TCP and gacyclidine “non‐NMDA” binding sites is the most appropriate way to further study the low‐affinity component of their specific binding. Obtaining reliable and specific pharmacological tools for those binding sites is of particular interest, since it is likely that they play a substantial role in the low neurotoxicity, and therefore tolerability, of gacyclidine, a new neuroprotective drug currently evaluated in clinical trials for the treatment of brain and spinal cord injuries. © 2002 Wiley‐Liss, Inc.
Stem cell repair of central nervous system injury
Authors: Cao Qilin , Benton Richard L. , Whittemore Scott R. 
Published: August 2002

AbstractNeural stem cells (NSCs) have great potential as a therapeutic tool for the repair of a number of CNS disorders. NSCs can either be isolated from embryonic and adult brain tissue or be induced from both mouse and human ES cells. These cells proliferate in vitro through many passages without losing their multipotentiality. Following engraftment into the adult CNS, NSCs differentiate mainly into glia, except in neurogenic areas. After engraftment into the injured and diseased CNS, their differentiation is further retarded. In vitro manipulation of NSC fate prior to transplantation and/or modification of the host environment may be necessary to control the terminal lineage of the transplanted cells to obtain functionally significant numbers of neurons. NSCs and a few types of glial precursors have shown the capability to differentiate into oligodendrocytes and to remyeliate the demyelinated axons in the CNS, but the functional extent of remyelination achieved by these transplants is limited. Manipulation of endogenous neural precursors may be an alternative therapy or a complimentary therapy to stem cell transplantation for neurodegenerative disease and CNS injury. However, this at present is challenging and so far has been unsuccessful. Understanding mechanisms of NSC differentiation in the context of the injured CNS will be critical to achieving these therapeutic strategies. © 2002 Wiley‐Liss, Inc.
Strategies for neuroprotection against L‐trans‐2,4‐pyrrolidine dicarboxylate‐induced neuronal damage during energy impairment in vitro
Authors: García Octavio , Massieu Lourdes 
Published: August 2002

AbstractIncreased levels of extracellular excitatory amino acids and failure of energy metabolism are two conditions associated with brain ischemia. In the present study we have combined the simultaneous inhibition of glutamate uptake and mitochondrial electron transport chain to simulate neuronal damage associated with brain ischemia. Results show that cerebellar granule neurons are not vulnerable to transient glutamate uptake inhibition by L‐trans‐pyrrolidine‐2,4‐dicarboxylate (PDC) despite the increase in the extracellular concentration of glutamate, unless they are simultaneously exposed to the mitochondrial toxins 3‐nitropropionic acid (3‐NP) or sodium azide. Cell damage was assessed by light microscopy observation, by reduction of 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT), and by the fluorescent markers for live and dead cells, calcein and ethidium homodimer, respectively. The protective effect of alternative energy substrates, such as pyruvate, acetoacetate, and β‐hydroxybutyrate against PDC‐induced neuronal death during 3‐NP exposure was studied and compared to the effects of the antioxidant vitamin E, the spin trapper α‐phenyl‐N‐tert‐butylnitrone (PBN), voltage‐dependent calcium channel antagonists, and glutamate receptor antagonists. Results show that neuronal damage can be efficiently prevented in the presence of pyruvate and the N‐methyl‐D‐aspartate (NMDA) receptor antagonist MK‐801, whereas the non‐NMDA receptor antagonist NBQX, acetoacetate, vitamin E, and PBN showed partial protection. In contrast, β‐hydroxybutyrate and voltage‐dependent calcium channels blockers did not show any protective effect at the concentrations tested. J. Neurosci. Res. 64:418–428, 2001. © 2001 Wiley‐Liss, Inc.
Mechanisms of cell death in primary cortical neurons and PC12 cells
Authors: Reimann‐Philipp Ulrich , Ovase Roma , Weigel Paul H. , Grammas Paula 
Published: August 2002

AbstractIncreasing evidence suggests that the regulation of neuronal cell death is complex. In this study we compared the neurotoxic effects of tumor necrosis factor‐α (TNFα), nitric oxide, and thrombin on primary rat cortical cell cultures and the neuronal PC12 cell line. Release of lactate dehydrogenase (LDH) and the intracellular accumulation of nucleosomes were used as indicators of necrosis and apoptosis, respectively. There was significant LDH release in both neuronal cell types, however, the pattern of LDH release was variable and agonist‐dependent. In response to the nitric oxide generator, sodium nitroprusside (SNP), cortical cells exhibited pronounced LDH release and dramatic morphologic changes, whereas in differentiated PC12 cells, TNFα evoked release of LDH with no associated morphologic changes. Both neuronal cell types, but not undifferentiated PC12 cells, responded to TNFα and thrombin with increased apoptosis. Caspase inhibition, but not antioxidant treatment, reduced nucleosome accumulation in primary cortical cells, but not in differentiated PC12 cells. In the differentiated PC12 cells, caspase inhibition reduced TNFα‐mediated LDH release, but not nucleosome accumulation. These data suggest mechanisms involved in neuronal cell death utilize multiple pathways that vary depending on the neurotoxic insult and are also influenced by subtle differences among neuronal cell phenotypes. J. Neurosci. Res. 64:654–660, 2001. © 2001 Wiley‐Liss, Inc.
Cholinergic modulation of synaptic physiology in deep layer entorhinal cortex of the rat
Authors: Cheong Mi Young , Yun Sung Hwan , Mook‐Jung Inhee , Joo Insoo , Huh Kyoon , Jung Min Whan 
Published: August 2002

AbstractWe have recently shown that cholinergic effects on synaptic transmission and plasticity in the superficial (II/III) layers of the rat medial entorhinal cortex (EC) are similar, but not identical, to those in the hippocampus (Yun et al. [2000] Neuroscience 97:671–676). Because the superficial and deep layers of the EC preferentially convey afferent and efferent hippocampal projections, respectively, it is of interest to compare cholinergic effects between the two regions. We therefore investigated the physiological effects of cholinergic agents in the layer V of medial EC slices under experimental conditions identical to those in the previous study. Bath application of carbachol (0.5 μM) induced transient depression of field potential responses in all cases tested (30 of 30; 18.5% ± 2.3%) and rarely induced long‐lasting potentiation (only 3 of 30; 20.4% ± 3.2% in successful cases). At
5 μM, carbachol induced transient depression only (20 of 20, 48.9% ± 2.8%), which was blocked by atropine
(10 μM). Paired‐pulse facilitation was enhanced during carbachol‐induced depression, suggesting presynaptic action of carbachol. Long‐term potentiation (LTP) could be induced in the presence of 10 μM atropine by theta burst stimulation, but its magnitude was significantly lower (9.1% ± 4.7%, n = 15) compared to LTP in control slices (22.4% ± 3.9%, n = 20). These results, combined with our previous findings, demonstrate remarkably similar cholinergic modulation of synaptic transmission and plasticity across the superficial and deep layers of EC. J. Neurosci. Res. 66:117–121, 2001. © 2001 Wiley‐Liss, Inc.
Precipitation seasonality in eastern and southern coastal Spain
Authors: Sumner G. , Homar V. , Ramis C. 
Published: August 2002

AbstractThe nature of the seasonality of precipitation in eastern and southern coastal Spain (including both the Mediterranean and the far southwestern Atlantic provinces) is examined using monthly precipitation values available for 410 sites for the period 1964–1993. Important contrasts are illustrated between eastern (Mediterranean) and southern (Atlantic) areas. In the east, seasonality is more subdued due to incursions of fronts from the north at all times of the year. In the far south, the months of July and August are almost completely dry, but the period October–February is wet due to incursions of active Atlantic frontal systems. In central areas (Almería, Murcia, Alacant, València and the Illes Balears) the significance of extensive severe thunderstorm development during September and October produces an autumn peak in precipitation amount. The spatial variation of precipitation seasonality is further examined using the seasonality index derived by Walsh and Lawler (Walsh PD, Lawler DM. 1981. Rainfall seasonality: description, spatial patterns and change through time. Weather 36: 201–208). Trends of this index through the 30‐year period are identified for some areas using linear regression on 5‐year running means of the index, and indicate that seasonality is increasing in the south (Andalucía), around the uplands of Catalunya (near Lleida) in the east, and in a few smaller areas in between. In the south, the increase in seasonality is due to a greater concentration of precipitation during the cooler part of the year, so that the period January–March is becoming drier, but October–December, wetter. The overall cool season precipitation remains much as for the present, though some evidence for drying is indicated for Málaga, Jaén and Granada. Precipitation in the normally dry month of July is also increasing. In upland Catalunya, there are indications of a greater concentration of cool season precipitation, with, notably, higher amounts in October and some evidence of warm season drying, notably in June. Copyright © 2001 Royal Meteorological Society
Lagged teleconnections between snow depth in northern Eurasia, rainfall in Southeast Asia and sea‐surface temperatures over the tropical Pacific Ocean
Authors: Ye Hengchun , Bao Zhenhao 
Published: August 2002

AbstractThis study shows that above‐(below‐)normal winter snow depth over European Russia and corresponding below‐(above‐)normal snow depth over central Siberia is associated with reduced (increased) summer monsoon rainfall over southern and western India and eastern Pakistan, and above‐(below‐)normal sea‐surface temperatures (SSTs) over the eastern and central tropical Pacific Ocean during the following winters. The connection is slightly stronger when snow depth over European Russia is above normal than below normal. These results are derived from an examination of 60 years (1936–1995) of winter snow depth data and SSTs, and 45 years (1951–1995) of summer precipitation records. The results of this study suggest that winter snow depth over the western rather than the eastern portion of Eurasia is critical to Southeast Asian summer monsoon rainfall and eastern tropical Pacific SSTs during the following seasons. Copyright © 2001 Royal Meteorological Society
Response of chironomids to Late Quaternary environmental change in the Taitao Peninsula, southern Chile
Authors: Massaferro Julieta , Brooks Stephen J. 
Published: August 2002

AbstractAn Erratum has been published for this article in Journal of Quaternary Science 17(7) 2002, 721.
There is conflicting evidence concerning the extent and timing of late Quaternary climate variability in southern South America and how this may be linked to climate change in the Northern Hemisphere. Critical unresolved questions include whether or not a cool period occurred in southern South America during the Younger Dryas Chronozone (YDC) (11 000–10 000 14C yr BP; 13 000–11 200 yr BP), and the timing of wet and dry phases during the Holocene. To date most evidence is from glacial, pollen and beetle records but, in an attempt to resolve these questions, we have used chironomid midges as an independent proxy in one of the first studies of its kind in Patagonia. We investigated the dynamics of midge assemblages during the Late‐glacial and Holocene at Lago Stibnite on the Taitao Peninsula, southern Chile (46°S). Changes in the midge assemblage suggest that the climate may have become cooler and drier during the YDC. During the Holocene there were cyclical changes in the midge assemblage that may have been in response to trophic change and/or to changes in precipitation when conditions appear to have been drier than today at 9400–6300 14C yr BP and 2400–1600 14C yr BP. Copyright © 2002 John Wiley & Sons, Ltd.
Raman spectroscopy of kaolinites using different excitation wavelengths
Authors: Frost Ray L. , Fredericks Peter M. , Kloprogge J. Theo , Hope Greg A. 
Published: August 2002

AbstractThe Raman spectra of both low‐ and high‐defect kaolinites in the hydroxyl stretching and low‐wavenumber region were obtained with excitation at three visible wavelengths of 633, 514 and 442 nm and a UV wavelength of 325 nm. The UV‐excited spectra were comparable to those excited by the visible wavelengths. The Raman spectra show hydroxyl stretching bands at 3621 cm−1 attributed to the inner hydroxyl, at 3692 and 3684 cm−1 attributed to the longitudinal and transverse optic modes of the inner surface hydroxyls and at 3668 and 3653 cm−1 assigned to the out‐of phase vibrations of the inner surface hydroxyls. Two bands were observed in the spectral profile at 3695 cm−1 for the high‐defect kaolinite at 3698 and 3691 cm−1 and were assigned to TO/LO splitting. An increase in relative intensity of the transverse optic mode is observed with decrease in laser wavelength. The intensity of the out‐of‐phase vibrations at 3668 and 3653 cm−1 of the inner surface hydroxyls shows a linear relationship with the longitudinal and transverse optic modes. In the low‐wavenumber region excellent correlation was found between the experimentally determined and the calculated band positions. Copyright © 2001 John Wiley & Sons, Ltd.
Vibrational spectroscopy of polymeric biomaterials
Authors: Taddei Paola , Tinti Anna , Fini Giancarlo 
Published: August 2002

AbstractThis review highlights the potential of vibrational spectroscopy for investigating the molecular structure of some polymeric materials used in biomedical applications in relation to their biocompatibility. Many types of polymers are used for biomedical purposes; depending on the application, bioresorbable or non‐bioresorbable (semi‐crystalline or amorphous) polymers are used. Among bioresorbable polymers, we focused on homopolymers and copolymers based on poly(lactic acid), poly(glycolic acid) and poly(ε‐caprolactone). Being a nondestructive technique, Raman spectroscopy proved particularly suitable for evaluating the molecular structure and crystallinity of bioresorbable polymers and their degradation products. For various biomedical applications, non‐degradable semi‐crystalline polymers have been widely employed; in this class of polymers, we concentrated on ultra‐high molecular weight polyethylene (UHMWPE) used in orthopaedic implants (total hip and knee joints). Vibrational spectroscopy appeared particularly suitable in studying the oxidation and crystallinity of UHMWPE. Copyright © 2001 John Wiley & Sons, Ltd.
Temperature‐dependent Raman and infrared spectra of nucleosides. II—Cytidine
Authors: Lee S. A. , Li J. , Anderson A. , Smith W. , Griffey R. H. , Mohan V. 
Published: August 2002

AbstractRaman and infrared (IR) spectra were recorded for crystalline cytidine samples at 298, 160, 75 and 10 K. Data were taken over the spectral range 20–4000 cm−1. The wavenumbers of most vibrational modes were found to increase as the temperature was lowered, but several peaks near 3000 cm−1 showed the opposite trend. A number of peaks split into multiplets at low temperature. No evidence was found of any structural phase transitions in this temperature range. Plausible assignments of all main observed features are suggested. Copyright © 2001 John Wiley & Sons, Ltd.
Multi‐skilled and multi‐faceted: a comparative survey of UK and Australian information systems and technology professionals
Authors: Kakabadse Andrew , Korac‐Kakabadse Nada 
Published: August 2002

Abstract

A comparative study of over 250 UK and Australian information systems and technology (IS/IT) managers and professionals reported in this paper shows that the Australian contingent exhibit a greater capability for being multi‐skilled and multi‐faceted than their UK counterparts.

The IS/IT function is greater represented on the boards of UK companies than Australian companies.

Both groups display a substantial capacity for working across matrix structures, driving through change and influencing line management on how to best utilise information systems in the enterprise.

Copyright © 2001 John Wiley & Sons, Ltd.
Using multinational strategic alliance negotiations to help ensure alliance success: an entrepreneurial orientation
Authors: Mockler Robert J. , Gartenfeld Marc E. 
Published: August 2002

Abstract

This paper discusses the strategic importance of the negotiation phase of multinational strategic alliance development. The focus is on the potential partner negotiation process that occurs prior to the signing of the alliance deal.
It explores ways in which negotiations can be effectively used to substantially improve the chances of success by providing practical guidelines that are useful for multinational managers.
The wide variety of activities and demands involved involves a contingent entrepreneurial management process that is examined here.

Copyright © 2001 John Wiley & Sons, Ltd.
Critical factors for enhancing creativity
Authors: McFadzean Elspeth 
Published: August 2002

Abstract
This article explores five factors that can influence creative thinking: namely Judgement: Freewheeling: Association: Stimulation and Expression.
These factors are used to develop a framework in order to categorize, compare and contrast different creative problem‐solving techniques.
The three categories developed in the framework are paradigm‐preserving techniques, paradigm‐stretching techniques and paradigm‐breaking techniques.
A number of practical implications are then presented including training, teambuilding and the reduction of apprehension and cognitive inertia.
The experience of forming business relationships in tourism
Authors: Watkins Mike , Bell Barry 
Published: August 2002

AbstractThis study examines the formation of business relationships among tourism organisations. A phenomenographic study conducted with 25 managers drawn from regional tourism organisations in Queensland, Australia revealed three qualitatively different but interrelated ways of experiencing relationships: as competition, co‐operation and collaboration. Differences among experiences were accounted for by the way managers defined the meanings of several dimensions common to each experience. The results suggest managers' experiences can be developmentally ordered on a continuum of relationships that demonstrate progressively more complex and inclusive approaches to forming relationships. Copyright © 2001 John Wiley & Sons, Ltd.
Copper and Iron: A landmark connection of two essential metals
Authors: Harris Edward D. 
Published: August 2002

AbstractResearch in the past millennium gave us formidable advances in the fields of Cu nutrition, biochemistry, animal and human health. Insights into Cu‐Fe interactions highlighted much significant advancement. The recognition that Cu was an essential mineral for Fe metabolism and hemoglobin biosynthesis traces back to a paper by Hart et al. at Wisconsin appearing in the first third of the century. This observation came at a time when the only known function of Cu was that of a constituent of hemocyanin pigment in some mollusks and crustacea. The Wisconsin group's studies were preceded by McHargue's work, which introduced glass‐lined cages to study trace mineral function, and in so doing, provided the first experimental evidence for Mn, Cu, and Zn essentiality. Here, we review the details of the experiments by Hart et al. that led to the discovery of copper's interconnection with Fe and important papers that have since given mechanistic clarity to the interaction. J. Trace Elem. Exp. Med. 14:207–210, 2001.
Essentiality and toxicity of trace elements: Principles and methods for assessment of risk from human exposure to essential trace elements
Authors: Nordberg G. , Sandström B. , Becking G. , Goyer R.A. 
Published: August 2002

AbstractRecommendations aimed at protecting the public from toxicity of essential elements have been developed separately from those recommendations aimed at protection from deficiency. Because of the uncertainties involved in evaluations, these recommendations have sometimes been in conflict, emphasizing the need for a new approach including a balanced consideration of nutritional as well as toxicological data.In developing these new principles of evaluation, some basic concepts based on interindividual variability in sensitivity to deficiency and toxicity must be considered. Such variation translates into one interval of (low) daily intakes, at which there is risk of developing deficiency, and another interval of (high) dietary intakes, at which toxicity may occur. In most instances there is a third set of intakes in between, which represents the acceptable range of oral intakes (AROI) in which no adverse effects occur. It must be noted, however, that such a range cannot be found that protects all persons from adverse effects. Those persons with genetically determined sensitivity may require higher intakes to avoid deficiency, or lower intakes to avoid toxicity than those defined by AROI. AROI is defined as protecting 95% of an unselected human population from even minimal adverse effects of deficiency or toxicity. J. Trace Elem. Exp. Med. 13:141–153, 2000.