bluuebunny/crossref_metadata_2025_split huggingface dataset:
Explaining outcomes in competition among foreign multinationals in a focal host market
Authors: Rangan Subramanian , Drummond Aldemir 
Published: January 2004

AbstractMultinational enterprises (MNEs) from different home regions now routinely confront one another in third markets. There is, however, little conceptual or theoretical literature on the determinants of outcome patterns in these contests. This paper offers a first attempt at systematic and parsimonious conceptualization of the issue. In Brazil, for instance, while U.S.‐based MNEs such as Coca‐Cola and IBM lead in their sectors, other leading U.S. MNEs including Citibank, GE, and Pfizer are outsold by European rivals that appear less competitive globally. Extending theory on the liability of foreignness and firm‐specific advantages, we contend that (i) the MNE whose home nation has greater ties to the focal host nation (along geographic, colonial, immigration, linguistic, and institutional dimensions) will lead in that host nation; and (ii) ties notwithstanding, if an MNE's firm‐specific advantages are so superior that it outsells a rival MNE in that rival's home market, then it will outsell that rival as well in the focal host market. Based on this we develop a conceptual framework, statistical analysis pertaining to MNE competition in Brazil, and three avenues for fruitful new research. Copyright © 2003 John Wiley & Sons, Ltd.
Exploration and exploitation alliances in biotechnology: a system of new product development
Authors: Rothaermel Frank T. , Deeds David L. 
Published: January 2004

AbstractWe link the exploration–exploitation framework of organizational learning to a technology venture's strategic alliances and argue that the causal relationship between the venture's alliances and its new product development depends on the type of the alliance. In particular, we propose a product development path beginning with exploration alliances predicting products in development, which in turn predict exploitation alliances, and that concludes with exploitation alliances leading to products on the market. Moreover, we argue that this integrated product development path is moderated negatively by firm size. As a technology venture grows, it tends to withdraw from this product development path to discover, develop, and commercialize promising projects through vertical integration. We test our model on a sample of 325 biotechnology firms that entered 2565 alliances over a 25‐year period. We find broad support for the hypothesized product development system and the moderating effect of firm size. Copyright © 2004 John Wiley & Sons, Ltd.
The value of restructuring in emerging economies: the case of the Czech Republic
Authors: Makhija Mona V. 
Published: January 2004

AbstractAlthough the value creating effect of firm restructuring which results in a reduction of internal markets (including spin‐offs, carve‐outs and other divestitures) is generally well accepted for U.S. firms, there is little evidence on the extent to which such arguments can be extended to firms in emerging economies. This study addresses this void in the literature by examining the issue of restructuring in the newly emerging economy of the Czech Republic. Several hypotheses relating to internal and external markets in emerging institutional environments are developed and tested using a large database of original and restructured Czech firms undergoing privatization. After controlling for factors such as size and performance, it is found that restructuring significantly reduced the value of firms, despite the general belief that Czech firms emerging from the communist era were highly overdiversified. This finding, while contradicting a majority of the work on restructured firms in the United States, nonetheless supports the notion that sizeable internal markets play an enhanced role in underdeveloped institutional environments. Copyright © 2004 John Wiley & Sons, Ltd.
The highly selective 5‐hydroxytryptamine (5‐HT)2A receptor antagonist, EMD 281014, significantly increases swimming and decreases immobility in male congenital learned helpless rats in the forced swim test
Authors: Patel Jignesh G. , Bartoszyk Gerd D. , Edwards Emmeline , Ashby Charles R. 
Published: January 2004

AbstractWe examined the effect of the highly selective 5‐hydroxytryptamine (5‐HT)2A receptor antagonist 7‐{4‐[2‐(4‐fluoro‐phenyl)‐ethyl]‐piperazine‐1‐carbonyl}‐1H‐indole‐3‐carbonitrile HCl (EMD 281014) in congenital learned helpless male rats in the forced swim test. The administration of EMD‐281014 (0.3–30 mg/kg i.p.) to congenital learned helpless rats dose‐dependently and significantly (at 10 and 30 mg/kg) decreased immobility and increased swimming compared to vehicle‐treated animals. Thus, EMD 281014 produces effects in the forced swim test resembling those of antidepressants. Synapse 52:73–75, 2004. © 2004 Wiley‐Liss, Inc.
Methamphetamine‐induced loss of striatal dopamine innervation in BDNF heterozygote mice does not further reduce D3 receptor concentrations
Authors: Joyce Jeffrey N. , Renish Lynn , Osredkar Tracy , Walro Jon M. , Kucera Jan , Dluzen Dean E. 
Published: January 2004

AbstractDepletion of dopamine (DA) reduces D3 receptor number, but D3 receptor expression is also regulated by brain‐derived neurotrophic factor (BDNF). We took advantage of transgenic heterozygous BDNF mutant mice (+/−) to determine if reduced BDNF and loss of DA fibers produced by methamphetamine were additive in their impact on D3 receptor number. We assessed selective markers of the dopaminergic system including caudate‐putamen DA concentrations and quantitative autoradiographic measurement of tyrosine hydroxylase (TH) levels, DA transporter (DAT), and DA D3 receptor binding between vehicle and methamphetamine‐treated BDNF +/− and their wildtype (WT) littermate control mice. Caudate‐putamen DA concentrations, TH and DAT levels were significantly reduced following methamphetamine treatment in both WT and BDNF +/− mice. The extent of methamphetamine‐induced reduction in TH and DAT was greater for the WT than BDNF +/− mice and DAT levels were also decreased to a greater extent in nucleus accumbens of WT as compared to BDNF +/− mice. Lower D3 receptor existed in caudate‐putamen and nucleus accumbens in BDNF +/− mice and these differences were not affected by methamphetamine treatment. Taken together, these results not only substantiate the importance of BDNF in controlling D3 receptor expression, but also indicate that a methamphetamine‐induced depletion of DA fibers fails to produce an additive effect with lowered BDNF for control of D3 receptor expression. In addition, the reduction of D3 receptor expression is associated with a decreased neurotoxic response to methamphetamine in BDNF +/− mice. Synapse 52:11–19, 2004. © 2004 Wiley‐Liss, Inc.
Ultrastructural localization of Leu5‐enkephalin immunoreactivity in mesocortical neurons and their input terminals in rat ventral tegmental area
Authors: Garzón Miguel , Pickel Virginia M. 
Published: January 2004

AbstractEnkephalin (ENK) immunoreactivity is widely distributed in the ventral tegmental area (VTA), where endogenous ENK and dynorphin opioid peptides are known to have opposing actions in reward, stress, cognition, and fear‐related behaviors. Many neurons in the VTA give rise to mesocortical projections terminating in the medial prefrontal cortex (mPFC), and these projections have been implicated to varying extents in all these functions. To determine whether there is a synaptic basis for ENK and/or dynorphin modulation of cortically projecting neurons within the VTA, we combined retrograde tract‐tracing from the mPFC with dual immunocytochemical‐labeling electron microscopy in the rat VTA. The retrograde tracer Fluorogold (FG) was microinjected into mPFC. At optimal survival periods, sections through the VTA were processed for immunolabeling of anti‐FG and a Leu5‐ENK antibody recognizing both ENK and dynorphin peptides. Over 26% of the retrogradely labeled neuronal somatodendritic profiles (n = 177) were contacted by ENK‐immunoreactive axonal profiles including small axons and axon terminals. The axon terminals varied in their subcellular distribution of ENK immunoreactivity and also differed in forming either inhibitory‐type (symmetric) or excitatory‐type (asymmetric) synapses. Many of the axonal profiles also were apposed to FG‐labeled somata or dendrites without forming recognizable synapses. Approximately one‐third of the mesocortical neuronal perikarya also showed sparsely distributed somatodendritic ENK‐immunoreactivity. Our results provide ultrastructural evidence that ENK and possibly dynorphin in the rat VTA have distributions consistent with involvement in diverse physiological actions affecting the output of mesocortical neurons, some of which also contain one or both peptides. Synapse 52:38–52, 2004. © 2004 Wiley‐Liss, Inc.
Effect of the acute and chronic administration of the selective 5‐HT6 receptor antagonist SB‐271046 on the activity of midbrain dopamine neurons in rats: An in vivo electrophysiological study
Authors: Minabe Yoshio , Shirayama Yukihiko , Hashimoto Kenji , Routledge Carol , Hagan Jim J. , Ashby Charles R. 
Published: January 2004

AbstractThis study examined the effect of the acute and repeated per os (p.o.) administration of the selective 5‐HT6 receptor antagonist SB‐271046, on the number, as well as the firing pattern of spontaneously active dopamine (DA) neurons in the rat substantia nigra pars compacta (SNC) and ventral tegmental area (VTA) in anesthetized male Sprague‐Dawley rats. This was accomplished using the technique of extracellular in vivo electrophysiology. A single p.o. administration of either 1, 3, or 10 mg/kg of SB‐271046 did not significantly alter the number of spontaneously active SNC DA neurons per stereotaxic electrode tract compared to vehicle‐treated animals. The acute administration of either 1 or 3 mg/kg of SB‐271046 did not significantly alter the number of spontaneously active VTA DA neurons. In contrast, a significant decrease in the number of spontaneously active VTA DA neurons was observed after a single administration of 10 mg/kg of SB‐271046 compared to vehicle‐treated animals. The acute p.o. administration of SB‐271046 significantly altered the firing pattern parameters of all (bursting + nonbursting DA neurons) DA neurons, particularly those in the VTA, compared to vehicle‐treated animals. The repeated p.o. administration (once per day for 21 days) of 1, 3, or 10 mg/kg of SB‐271046 did not significantly alter the number of spontaneously active VTA DA neurons compared to vehicle‐treated animals. The repeated administration of 3 or 10 mg/kg of SB‐271046 significantly increased the number of spontaneously active SNC DA neurons compared to vehicle controls. Overall, the repeated administration of SB‐271046 had relatively little effect on the firing pattern of midbrain DA neurons. The results obtained following the chronic administration of SB‐271046 show that this compound has a profile different from that of typical or atypical antipsychotic drugs in this model. Clinical studies are required to understand what role 5‐HT6 receptor blockade might eventually play in the treatment of schizophrenia. Synapse 52:20–28, 2004. © 2004 Wiley‐Liss, Inc.
Effects of 6‐cyano‐7‐nitroquinoxaline‐2,3‐dione on nicotinic receptor subunit transcript expression in the rat brain
Authors: McCullumsmith Robert E. , Semins Michelle J. , Meador‐Woodruff James H. 
Published: January 2004

AbstractThe nicotinic cholinergic system exerts potent modulatory effects on glutamatergic neurotransmission, an effect mediated in part by increased glutamate release following activation of presynaptic nicotinic cholinergic receptors. Ionotropic glutamate receptor agonists also stimulate release of acetylcholine, suggesting that these neurotransmitter systems reciprocally regulate one another. We investigated an interface between the nicotinic cholinergic and glutamatergic systems by measuring nicotinic receptor subunit transcript expression following administration of 6‐cyano‐7‐nitroquinoxaline‐2,3‐dione (CNQX), an antagonist of the AMPA and kainate subtypes of glutamate receptors. Using [35S] in situ hybridization, we measured expression of α2, α3, α4, α5, α7, β2, β3, and β4 nicotinic receptor subunit transcripts in the rat forebrain. Following 7 days of treatment with vehicle or CNQX (1 mg/kg/day or 10 mg/kg/day), changes in nicotinic receptor subunit transcript expression were restricted to subunits that form heteromeric receptors. We found increased levels of transcripts for α2 and β2 nicotinic receptor subunits in the hippocampus, decreased α4 subunit transcripts in the medial habenula and amygdala, and increased β2 subunit transcripts in the septum and piriform cortex. We did not detect changes in expression of transcripts for the α7 subunit, which forms homomeric nicotinic receptors. Our findings indicate that expression of nicotinic cholinergic receptor subunit transcripts are regulated in a subunit‐ and region‐specific fashion by CNQX, an antagonist of non‐NMDA ionotropic glutamate receptors. Synapse 52:62–72, 2004. © 2004 Wiley‐Liss, Inc.
Aging impairs the late phase of long‐term potentiation at the medial perforant path‐CA3 synapse in awake rats
Authors: Dieguez Dario , Barea‐Rodriguez Edwin J. 
Published: January 2004

AbstractThe effects of aging on long‐term potentiation (LTP) in the dentate gyrus (DG) and CA1 are well documented, but LTP at the medial perforant path (MPP)‐CA3 synapse of aged animals has remained unexplored. Because the MPP‐DG and Schaffer‐collateral‐CA1 synapses account for only about 20% of total hippocampal synapses, global understanding of how aging affects hippocampal plasticity has remained limited. Much is known about LTP induction in the hippocampal formation, whereas the mechanisms that regulate LTP maintenance are less understood, especially during aging. We investigated the effects of aging on MPP‐CA3 LTP induction and maintenance in awake rats. As is the case in the DG and CA1, high‐frequency stimulation‐induced LTP at the MPP‐CA3 synapse is normal in aged rats. These data indicate that N‐methyl‐D‐aspartate (NMDA) receptor‐mediated processes are intact at the MPP‐CA3 synapse in aged rats. In contrast, aging impaired the magnitude and duration of MPP‐CA3 LTP over a period of days. Also, these data are consistent with reports that area CA3 is especially susceptible to age‐related changes. Our data suggest that aging impairs mechanisms that regulate the late phase of MPP‐CA3 LTP and contribute to a more global understanding of how aging affects hippocampal plasticity. Synapse 52:53–61, 2004. © 2004 Wiley‐Liss, Inc.
Development of an integrative transformation system for the opportunistic pathogenic yeast Candida lusitaniae using URA3 as a selection marker
Authors: François Fabienne , Chapeland‐Leclerc Florence , Villard Jean , Noël Thierry 
Published: January 2004

AbstractThe nucleotide sequence of the URA3 gene encoding orotidine‐5′‐phosphate decarboxylase (OMP DCase) of the human opportunistic pathogen yeast Candida lusitaniae was determined by degenerate PCR and chromosome walking. Deduced amino acid sequence showed strong homologies (59–85% identity) with OMP DCases of different Saccharomycetales and allowed identification of the known conserved domains. Very close upstream from the URA3 gene, the 3′‐end of a gene encoding a Gea2‐like protein was identified. A non‐revertible C. lusitaniae ura3 mutant was selected on the basis of 5‐fluoroorotic acid resistance. The mutation was a single point mutation resulting in the amino acid substitution D95V in a highly conserved domain, and in a concomitant EcoRV restriction site polymorphism. The mutant strain was successfully transformed to prototrophy following electroporation with the URA3 gene cloned in an integrative vector, with frequencies of 100–200 transformants per µg of DNA. Southern blot analysis revealed that almost all transformants were derived from homologous recombination events at the resident locus. The GeneBank Accession No. for C. lusitaniae URA3 gene is AF450297. Copyright © 2003 John Wiley & Sons, Ltd.
[URE3] prion propagation is abolished by a mutation of the primary cytosolic Hsp70 of budding yeast
Authors: Tibor Roberts B. , Moriyama Hiromitsu , Wickner Reed B. 
Published: January 2004

Abstract[URE3] and [PSI+] are infectious protein forms of the Saccharomyces cerevisiae Ure2p and Sup35p, respectively. We isolated an allele of SSA2, the primary cytosolic Hsp70, in a screen for mutants unable to maintain [URE3]. Designated ssa2‐10, the mutation results in a leucine substitution for proline 395, a conserved residue of the peptide‐binding domain. This allele also unexpectedly destabilizes [URE3] in newly formed heterozygotes: [URE3] is either absent in heterozygotes formed by crossing wild‐type [URE3] cells with ssa2‐10 mutants, or present and fully stable. SSA2 deletion mutants are weakly capable of maintaining [URE3]. The ssa2‐10 allele is compatible with propagation of [PSI+]. However, in combination with a deletion of SSA1, ssa2‐10 eliminates the nonsense‐suppression phenotype of [PSI+] cells. Copyright © 2003 John Wiley & Sons, Ltd.
Ion channel activity by Pichia membranifaciens killer toxin
Authors: Santos A. , Marquina D. 
Published: January 2004

AbstractThe cytocidal effect of Pichia membranifaciens killer toxin on Candida boidinii cells was studied. The halotolerant yeast P. membranifaciens CYC 1106 produces a unique 18 kDa killer toxin that exerts its killer activity against C. boidinii IGC 3430 only in the presence of NaCl. Metabolic events associated with the loss of C. boidinii IGC 3430 viability were quantitatively identical to those known to occur with K1 killer toxin‐treated sensitive strains of Saccharomyces cerevisiae. The death of sensitive cells was characterized by a leakage of potassium, an influx of sodium and a decrease in intracellular pH. These effects occurred prior to and concomitantly with cell death, indicating that they were primary effects of the action of the toxin. Here we report that this protein forms ion‐permeable channels in liposome membranes. These channels are freely permeable to common physiological ions. We suggest that channel formation is the cytotoxic mechanism of action of P. membranifaciens killer toxin. The channels described here are sufficiently non‐selective to mediate cell death through a discharge of cellular membrane potential and changes in ionic homeostasis. No specific effects against killer toxin‐treated sensitive cells were observed when the cell cycle was analysed. Copyright © 2003 John Wiley & Sons, Ltd.
Isolation of a GPD gene from Debaryomyces hansenii encoding a glycerol 3‐phosphate dehydrogenase (NAD+)
Authors: Thomé Patricia E. 
Published: January 2004

AbstractA gene homologous to GPD1, coding for glycerol‐3‐phosphate dehydrogenase (sn‐glycerol 3‐phosphate: NAD+ oxidoreductase, EC 1.1.1.8), has been isolated from the halophilic yeast Debaryomyces hansenii by complementation of a Saccharomyces cerevisiae gpd1Δ mutant. DNA sequencing of the complementing genomic clone indicated the existence of an open reading frame encoding a protein with 369 amino acids. Comparative analysis of the deduced amino acid sequence showed high similarity to homologous genes described for other eukaryotic GPD enzymes. The sequence has been submitted to the GenBank database under Accession No. AY333427. Copyright © 2003 John Wiley & Sons, Ltd.
Binding of Cdc48p to a ubiquitin‐related UBX domain from novel yeast proteins involved in intracellular proteolysis and sporulation
Authors: Decottignies Anabelle , Evain Aude , Ghislain Michel 
Published: January 2004

AbstractThe Cdc48/p97 AAA‐ATPase functions in membrane fusion and ubiquitin‐dependent protein degradation. Here, we show that, in yeast, Cdc48p interacts with three novel proteins, Cuil–3p, which contain a conserved ubiquitin‐related (UBX) domain. Cui2p and Cui3p are closely related, interact with each other, and are localized at the perinuclear membrane. Cdc48p binds directly the UBX domain of Cui3p in vitro. Multiple deletions of the CUI1, CUI2 and CUI3 genes confer deficiency in sporulation and degradation of model ubiquitin–protein fusions. The Cuil–3 proteins were also found to interact with Ufd3p, a WD repeat protein known to associate with Cdc48p. Together, these results indicate that the Cuil–3 proteins form complexes that are components of the ubiquitin–proteasome system. Copyright © 2003 John Wiley & Sons, Ltd.
Endogenous NADPH‐dependent aldose reductase activity influences product formation during xylose consumption in recombinant Saccharomyces cerevisiae
Authors: Träff‐Bjerre K. L. , Jeppsson M. , Hahn‐Hägerdal B. , Gorwa‐Grauslund M.‐F. 
Published: January 2004

AbstractIntroduction of the xylose pathway from Pichia stipitis into Saccharomyces cerevisiae enables xylose utilization in recombinant S. cerevisiae. However, xylitol is a major by‐product. An endogenous aldo‐keto reductase, encoded by the GRE3 gene, was expressed at different levels in recombinant S. cerevisiae strains to investigate its effect on xylose utilization. In a recombinant S. cerevisiae strain producing only xylitol dehydrogenase (XDH) from P. stipitis and an extra copy of the endogenous xylulokinase (XK), ethanol formation from xylose was mediated by Gre3p, capable of reducing xylose to xylitol. When the GRE3 gene was overexpressed in this strain, the xylose consumption and ethanol formation increased by 29% and 116%, respectively. When the GRE3 gene was deleted in the recombinant xylose‐fermenting S. cerevisiae strain TMB3001 (which possesses xylose reductase and XDH from P. stipitis, and an extra copy of endogenous XK), the xylitol yield decreased by 49% and the ethanol yield increased by 19% in anaerobic continuous culture with a glucose/xylose mixture. Biomass was reduced by 31% in strains where GRE3 was deleted, suggesting that fine‐tuning of GRE3 expression is the preferred choice rather than deletion. Copyright © 2003 John Wiley & Sons, Ltd.
Selective inhibition of the growth of cancer cells by diterpenes selected with embryonic cells of Xenopus
Authors: Miyata Shohei , Wang Li‐Yan , Wang Nai‐Li , Yao Xin‐Sheng , Kitanaka Susumu 
Published: January 2004

AbstractWe used Xenopus embryo cells with a cell cycle of 20–30 min to detect inhibitory effects on cell proliferation. Inhibition of proliferation was observed when isolated embryonic cells were incubated for 16 h in a simple salt solution containing the well‐known anticancer drugs 5‐fluorouracil and adriamycin. In addition, three diterpene compounds isolated from the anticancer herbal medicine kansui: kansuinin B, 20‐OD‐ingenol Z, and 20‐OD‐ingenol E specifically inhibited the proliferation of isolated embryonic cells. The inhibitory compounds selected using the embryonic cells also inhibited proliferation of certain mammalian cell types.
Constitutive overexpression of the integral membrane protein Itm2A enhances myogenic differentiation of C2C12 cells
Authors: Van Den Plas Dave , Merregaert Joseph 
Published: January 2004

AbstractIntegral membrane protein 2A (Itm2A) is a transmembrane protein belonging to a family composed of at least two other members, Itm2B and Itm2C, all of them having a different expression pattern. The protein serves as a marker for early stages in chondrogenesis and T‐cell development. Itm2A is also highly expressed in skeletal muscle. In order to understand the role of Itm2A in muscle development, we constitutively overexpressed exogenous Itm2A in C2C12 myoblast cells. Several clones expressing high levels of Itm2a were isolated and characterized. Overexpression was associated with enhanced tube formation and the appearance of multinuclear cells. Gene expression analysis demonstrated that muscle creatin kinase was upregulated in the presence of exogenous Itm2A. Interestingly, proliferation rates were not altered in the undifferentiated myoblast C2C12 cells. These results demonstrate that overexpression of Itm2a in C2C12 enhances myogenic differentiation in vitro.