bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spike-Timing Codes Enhance the Representation of Multiple Simultaneous Sound-Localization Cues in the Inferior Colliculus
Authors: Chase Steven M. , Young Eric D. 
Published: April 2006

To preserve multiple streams of independent information that converge onto a neuron, the information must be re-represented more efficiently in the neural response. Here we analyze the increase in the representational capacity of spike timing over rate codes using sound localization cues as an example.The inferior colliculus receives convergent input from multiple auditory brainstem nuclei, including sound localization information such as interaural level differences (ILDs), interaural timing differences (ITDs), and spectral cues. Virtual space techniques were used to create stimulus sets varying in two sound-localization parameters each. Information about the cues was quantified using a spike distance metric that allows one to separate contributions to the information arising from spike rate and spike timing.Spike timing enhances the representation of spectral and ILD cues at timescales averaging 12 ms. ITD information, however, is carried by a rate code. Comparing responses to frozen and random noise shows that the temporal information is mainly attributable to phase locking to temporal stimulus features, with an additional first-spike latency component. With rate-based codes, there is significant confounding of information about two cues presented simultaneously, meaning that the cues cannot be decoded independently. Spike-timing-based codes reduce this confounded information. Furthermore, the relative representation of the cues often changes as a function of the time resolution of the code, implying that information about multiple cues can be multiplexed onto individual spike trains.
“Mir”acles in hox gene regulation
Authors: Chopra Vivek S. , Mishra Rakesh K. 
Published: April 2006

AbstractMicro RNAs (miRNAs) have been shown to control many cellular processes including developmental timing in different organisms. The prediction that miRNAs are involved in regulating hox genes of flies and mouse is quite a recent idea and is supported by the finding that mir‐196 represses Hoxb8 gene expression. The non‐coding regions that encode these miRNAs are also conserved across species in the same way as other mechanisms that regulate expression of hox genes. On the contrary, until now no homeotic phenotype, a hallmark of any hox gene mutation, had been associated with any hox miRNA. Recent work on bithorax complex miRNA (miR–iab‐4–5p) shows, for the first time, that miRNAs can lead to homeotic transformation. This miRNA regulates Ultrabithorax (Ubx) and results in the transformation of haltere to wing.1 This study unveils a new complexity and finesse to the regulation of hox gene expression pattern that is needed for determining the anteroposterior body axis in all bilaterians. BioEssays 28: 445–448, 2006. © 2006 Wiley Periodicals, Inc.
Functional diversity of FGF‐2 isoforms by intracellular sorting
Authors: Sørensen Vigdis , Nilsen Trine , Wiȩdłocha Antoni 
Published: April 2006

AbstractRegulation of the subcellular localization of certain proteins is a mechanism for the regulation of their biological activities. FGF‐2 can be produced as distinct isoforms by alternative initiation of translation on a single mRNA and the isoforms are differently sorted in cells. High molecular weight FGF‐2 isoforms are not secreted from the cell, but are transported to the nucleus where they regulate cell growth or behavior in an intracrine fashion. 18 kDa FGF‐2 can be secreted to the extracellular medium where it acts as a conventional growth factor by binding to and activation of cell‐surface receptors. Furthermore, following receptor‐mediated endocytosis, the exogenous FGF‐2 can be transported to the nuclei of target cells, and this is of importance for the transmittance of a mitogenic signal. The growth factor is able to interact with several intracellular proteins. Here, the mode of action and biological role of intracellular FGF‐2 are discussed. BioEssays 28: 504–514, 2006. © 2006 Wiley Periodicals, Inc.
Structural and functional diversity of adaptor proteins involved in tyrosine kinase signalling
Authors: Csiszár Ágnes 
Published: April 2006

AbstractAdaptors are proteins of multi‐modular structure without enzymatic activity. Their capacity to organise large, temporary protein complexes by linking proteins together in a regulated and selective fashion makes them of outstanding importance in the establishment and maintenance of specificity and efficiency in all known signal transduction pathways. This review focuses on the structural and functional characterisation of adaptors involved in tyrosine kinase (TK) signalling. TK‐linked adaptors can be distinguished by their domain composition and binding specificities. However, such structural classifications have proven inadequate as indicators of functional roles. A better way to understand the logic of signalling networks might be to look at functional aspects of adaptor proteins such as signalling specificity, negative versus positive contribution to signal propagation, or their position in the signalling hierarchy. All of these functions are dynamic, suggesting that adaptors have important regulatory roles rather than acting only as stable linkers in signal transduction. BioEssays 28: 465–479, 2006. © 2006 Wiley Periodicals, Inc.
Lean consumption and its influence on brand
Authors: Truch Edward 
Published: April 2006

Abstract

The continuing growth of the knowledge‐based economy is driving the quest for better understanding of the intangible drivers of wealth creation. American and European models for linking customer satisfaction to corporate and national performance have been established and will continue to be tested and developed. One of the challenges of modelling consumer behaviour is the effect of changing lifestyles. This paper describes a study of UK shoppers which explores the influence of lean consumption, the degree to which the shopping and post‐purchase experience is hassle free and timely, on the warmth of consumers' feelings towards the brand. The study operationalises the construct of lean consumption and finds that it is indeed a significant driver of brand warmth. This leads to clear implications for manufacturers and retailers and the ways in which they innovate and develop their products and services.

Copyright © 2006 John Wiley & Sons, Ltd.
Effect of serotonin‐acting agents on the serotonin content of immune cells. A peculiar observation
Authors: Pállinger Éva , Csaba G. 
Published: April 2006

AbstractThe effect of the tryptophan hydroxylase inhibitor, PCPA methylester, the serotonin reuptake inhibitor fluoxetine and MAO‐A inhibitor clorgyline on the serotonin content of rat immune cells was studied, using labelled antibodies and flow cytometry. Each molecule significantly increased in males the serotonin concentration of peritoneal lymphocytes and the monocyte‐macrophage‐granulocyte group (mo‐gran), however the agents were ineffective towards mast cells. In females fluoxetine and clorgyline increased the serotonin concentration in peritoneal lymphocytes and mo‐gran. Fluoxetine also increased the serotonin level in mast cells. Thymus was absolutely resistant to the drugs in both genders. The results call attention (1) to the reverse effect of serotonin‐acting agents on immune cells, (2) to the influence of the milieu where the cell is located and (3) the effect of gender. Copyright © 2006 John Wiley & Sons, Ltd.
Differences between first and subsequent rounds of the MRISC breast cancer screening program for women with a familial or genetic predisposition
Authors: Kriege Mieke , Brekelmans Cecile T. M. , Boetes Carla , Muller Sara H. , Zonderland Harmine M. , Obdeijn Inge Marie , Manoliu Radu A. , Kok Theo , Rutgers Emiel J. T. , de Koning Harry J. , Klijn Jan G. M. ,   Dutch MRI Screening (MRISC) Study Group
Published: April 2006

AbstractBACKGROUNDWithin the Dutch MRI Screening (MRISC) study, a Dutch multicenter screening study for hereditary breast cancer, the authors investigated whether previously reported increased diagnostic accuracy of magnetic resonance imaging (MRI) compared with mammography would be maintained during subsequent screening rounds.METHODSFrom November 1999 to October 2003, 1909 eligible women were included in the study. Screening parameters and tumor characteristics of different rounds were calculated and compared. The authors defined 3 different types of imaging screening rounds: first round in women never screened by imaging before, first round in women screened by imaging (mainly mammography) before, and subsequent rounds.RESULTSThe difference in sensitivity for invasive cancers between mammography and MRI was largest in the first round of women previously screened with mammography (20.0 vs. 93.3%; P = .003), but also in subsequent rounds, there was a significant difference in favor of MRI (29.4 vs. 76.5%; P = .02). The difference in false‐positive rate between mammography and MRI was also largest in the first round of women previously screened with mammography (5.5 vs. 14.0%; P<.001), and it remained significant in subsequent rounds (4.6 vs. 8.2%; P<.001). Screen‐detected tumors were smaller and more often lymph node negative than symptomatic tumors in age‐matched control patients, but no major differences in tumor stage were found between tumors detected at subsequent rounds compared with those in the first round.CONCLUSIONSIn subsequent rounds, a significantly higher sensitivity and better discriminating capacity of MRI compared with mammography was maintained, and a favorable tumor stage compared with age‐matched symptomatic controls. As results of these subsequent screening rounds were most predictive for long‐term effects, the authors expect that this screening program will contribute to a decrease of breast cancer mortality in these high‐risk women. Cancer 2006. © 2006 American Cancer Society.
P2X2receptors on ganglion and amacrine cells in cone pathways of the rat retina
Authors: Puthussery Theresa , Fletcher Erica L. 
Published: April 2006

AbstractExtracellular ATP is known to mediate fast, excitatory neurotransmission through activation of ionotropic P2X receptors. In this study, the localization of the P2X2receptor (P2X2R) subunit was studied in rat retina by using immunofluorescence immunohistochemistry and preembedding immunoelectron microscopy. The P2X2R was observed in large ganglion cells as well as in a subset of amacrine cells. Double labeling revealed that 96% of all P2X2R‐immunoreactive amacrine cells showed γ‐aminobutyric acid (GABA) immunoreactivity. Subsets of P2X2R‐immunoreactive amacrine cells expressed nitric oxide synthase and substance P; however, no colocalization was observed with choline acetyltransferase, vasoactive intestinal peptide, or tyrosine hydroxylase. Nearest‐neighbor analysis confirmed that P2X2Rs were expressed by a heterogeneous population of amacrine cells. The synaptic connectivity of P2X2R amacrine cells was also investigated. It was interesting that P2X2R‐immunoreactive amacrine cell dendrites stratified in the sublaminae of the inner plexiform layer occupied by cone, but not rod bipolar cell axon terminals. Immunoelectron microscopy revealed that P2X2‐immunoreactive amacrine cell processes were associated with cone bipolar cell axon terminals as well as other conventional synapses in the inner plexiform layer. Taken together, these data provide further evidence for the involvement of extracellular ATP in neuronal signaling in the retina, particularly within cone pathways. J. Comp. Neurol. 496:595–609, 2006. © 2006 Wiley‐Liss, Inc.
EphA7‐ephrin‐A5 signaling in mouse somatosensory cortex: Developmental restriction of molecular domains and postnatal maintenance of functional compartments
Authors: Miller Katherine , Kolk Sharon M. , Donoghue Maria J. 
Published: April 2006

AbstractMembers of the Eph family of receptor tyrosine kinases and their ligands, the ephrins, are expressed in distinct patterns in the forming cortex. EphA7 is expressed early in cortical development, becoming concentrated in anterior and posterior domains, whereas ephrin‐A5 is expressed later in corticogenesis, highest in the middle region that has low levels of EphA7. The EphA7 gene produces full‐length and truncated isoforms, which are repulsive and adhesive, respectively. Analysis of cortical RNA expression demonstrates that proportions of these isoforms change with time, from a more repulsive mix during embryogenesis to a more permissive mix postnatally. To examine how EphA7 and ephrin‐A5 influence the formation of cortical regions, EphA7−/− mice were analyzed. Within the cortex of EphA7−/− mice, the distribution of ephrin‐A5 was more extensive, encompassing its usual medial domain but also extending more posteriorly toward the occipital pole. Moreover, relative levels of ephrin‐A5 along the cortex's anatomical axes changed in EphA7−/− animals, creating less striking shifts in ligand abundance. Furthermore, in vivo functional studies revealed that EphA7 exerts a repulsive influence on ephrin‐A5‐expressing cells during corticogenesis. In contrast, EphA7 appears to mediate permissive interactions in the postnatal cortex: the area of somatosensory cortex was significantly reduced in EphA7−/− mice. A similar reduction was present in ephrin‐A5−/− animals and a more pronounced decrease was observed in EphA7/ephrin‐A5−/− cortex. Taken together, this study supports a role for EphA7 and ephrin‐A5 in the establishment and maintenance of certain cortical domains and suggests that the nature of their interactions changes with cortical maturity. J. Comp. Neurol. 496:627–642, 2006. © 2006 Wiley‐Liss, Inc.
Subpopulations of neurons expressing parvalbumin in the human amygdala
Authors: Pantazopoulos Harry , Lange Nicholas , Hassinger Linda , Berretta Sabina 
Published: April 2006

AbstractAmygdalar intrinsic inhibitory networks comprise several subpopulations of γ‐aminobutyric acidergic neurons, each characterized by distinct morphological features and clusters of functionally relevant neurochemical markers. In rodents, the calcium‐binding proteins parvalbumin (PVB) and calbindin D28k (CB) are coexpressed in large subpopulations of amygdalar interneurons. PVB‐immunoreactive (‐IR) neurons have also been shown to be ensheathed by perineuronal nets (PNN), extracellular matrix envelopes believed to affect ionic homeostasis and synaptic plasticity. We tested the hypothesis that differential expression of these three markers may define distinct neuronal subpopulations within the human amygdala. Toward this end, triple‐fluorescent labeling using antisera raised against PVB and CB as well as biotinylated Wisteria floribunda lectin for detection of PNN was combined with confocal microscopy. Among the 1,779 PVB‐IR neurons counted, 18% also expressed CB, 31% were ensheathed in PNN, and 7% expressed both CB and PNN. Forty‐four percent of PVB‐IR neurons did not colocalize with either CB or PNN. The distribution of each of these neuronal subgroups showed substantial rostrocaudal gradients. Furthermore, distinct morphological features were found to characterize each neuronal subgroup. In particular, significant differences relative to the distribution and morphology were detected between PVB‐IR neurons expressing CB and PVB‐IR neurons wrapped in PNNs. These results indicate that amygdalar PVB‐IR neurons can be subdivided into at least four different subgroups, each characterized by a specific neurochemical profile, morphological characteristics, and three‐dimensional distribution. Such properties suggest that each of these neuronal subpopulations may play a specific role within the intrinsic circuitry of the amygdala. J. Comp. Neurol. 496:706–722, 2006. © 2006 Wiley‐Liss, Inc.
Sex differences in the anatomical and functional organization of the periaqueductal gray‐rostral ventromedial medullary pathway in the rat: A potential circuit mediating the sexually dimorphic actions of morphine
Authors: Loyd Dayna R. , Murphy Anne Z. 
Published: April 2006

AbstractPrevious studies have demonstrated that morphine, administered systemically or directly into the periaqueductal gray (PAG), produces a significantly greater degree of antinociception in males in comparison with females. Because the midbrain PAG and its descending projections to the rostral ventromedial medulla (RVM) constitute an essential neural circuit for opioid‐based analgesia, the present studies were conducted to determine whether sex differences in the anatomical organization of the PAG‐RVM pathway, and its activation during persistent inflammatory pain, could account for sex‐based differences in opioid analgesia. In the rat, retrograde tracing was combined with Fos immunocytochemistry to investigate sexual dimorphism in the organization of the PAG‐RVM circuit and its activation by persistent inflammatory pain induced by intraplantar injection of complete Freund's adjuvant (CFA). The ability of morphine to suppress the activation of the PAG‐RVM circuit was also examined. Sexually dimorphic retrograde labeling was observed within the dorsomedial and lateral/ventrolateral PAG at all rostrocaudal levels, with females having significantly more PAG‐RVM output neurons in comparison with males. While no sex differences were noted in the activation of the PAG by persistent inflammatory pain, significantly more PAG‐RVM cells were activated in males in comparison with females. Systemic administration of morphine significantly suppressed CFA‐induced Fos in the PAG in males only. The results of these studies demonstrate that both the anatomical organization and the functional activation of the PAG‐RVM circuit are sexually dimorphic and may provide the anatomical substrate for sex‐based differences in morphine analgesia. J. Comp. Neurol. 496:723–738, 2006. © 2006 Wiley‐Liss, Inc.
Analysis of individual data from bead‐based assays (“bead arrays”)
Authors: Jacobson James W. , Oliver Kerry G. , Weiss Christy , Kettman John 
Published: April 2006

AbstractIntroduction:Typically, bead‐based assays (“bead arrays”) use the mean or median value of a population of measurements to judge ligand binding or other activity, which results in a change in fluorescence intensity. Individual bead measurements are used here to calculate population parameters integral to the measurement of a bead array.Methods:Using a commercially‐available instrument designed for bead array measurements, a set of beads were labeled with biotin and then titrated with PE‐Streptavidin. Data were collected under normal machine conditions as well as variations.Results:The “sensitivity” of the measurements was determined using parametric and nonparametric statistical methods as well as regression analysis over a limited range of the titration (concentration vs. response profile).Conclusions:Results at low ligand concentrations suggest that precise measurements with bead array systems require a large number of individual bead measurements to be acquired. Individual bead measurements should be used to determine the mean and confidence intervals for the calculated measurements. These results also apply to regression analysis of concentration‐response profiles. Furthermore, features of the instrument can be manipulated to achieve increased sensitivity and detection of lower amounts of ligand bound to the bead populations. © 2006 International Society for Analytical Cytology
SPLAT: a unified SIP services platform for VoIP applications
Authors: Singh Aameek , Acharya Arup , Mahadevan Priya , Shae Zon‐Yin 
Published: April 2006

AbstractThe steady improvements in the networking infrastructure and ever increasing broadband penetration has fueled the resurgence of voice‐over‐IP (VoIP). One of the important contributors to this growth has also been the development and wide acceptance of the session initiation protocol (SIP). However, the current usage of SIP requires a per‐application deployment (each application using its own SIP stack). In addition to shared port number problems, this leads to a narrow development of SIP based services, even though SIP, as a protocol, offers incredible opportunities for enabling various applications simultaneously.In this paper, we propose SPLAT—a unified SIP platform, consisting of a client‐side SIP service and supporting network infrastructure blocks, that provide unified mechanisms to execute generic SIP functions through an exported higher level API. Applications can leverage the API and ready‐made building blocks for creating richer interfaces without significant and often repeated development effort, e.g. a conferencing server coupled with a gaming server can provide context‐aware audio conferencing between occupants of a particular game room. Importantly, the SPLAT framework is available to all applications including the ones not inherently based on SIP and thus presents a great opportunity for enhancing such applications. The SIP service API is designed to be extensible and provides novel higher level functional primitives like ad hoc conferencing and seamless transition of sessions. In addition, it also exports a low level interface for specialized applications that need direct access to SIP call flows. Another feature of the service is that it allows a user to plug‐in an end device (softphone, IP phone, PSTN phone) of his/her choice on a per‐session basis. We demonstrate the richness of the API by describing prototypes for enhancing various applications as well as new converged applications. Copyright © 2006 John Wiley & Sons, Ltd.
Scalable and efficient QoS support for SIP‐signalled voice calls
Authors: Molina Maurizio , Quittek Jürgen , Brunner Marcus , Melia Telemaco 
Published: April 2006

AbstractThis paper proposes an extension of the functionality of a SIP proxy server for providing QoS to SIP‐signalled voice over IP calls in a scalable and efficient way. The basic concept lies in aggregating SIP calls into bandwidth‐provisioned trunks and on admitting calls on trunks only within the limit of their bandwidth. The SIP proxy server derives bandwidth requirements of SIP calls directly from parsed SIP messages. The bandwidth of the logical trunks can be dynamically changed. With a moderate trunk over‐sizing, the trunk resizing rate can be kept much lower than the call arrival process. The approach scales well in a scenario where a centralized entity (bandwidth broker) is in charge of managing all the trunks of a given domain. We present simulation results that confirm this good scalability. The functionality and scalability of the proposed approach is compared with other ones currently discussed in the IETF or in the literature. Copyright © 2006 John Wiley & Sons, Ltd.