bluuebunny/crossref_metadata_2025 huggingface dataset:
Measurement and Modelling of Perceived Slant in Surfaces Represented by Freely Viewed Line Drawings
Authors: Cowie Roddy
Published: January 2007

Simple pictures under everyday viewing conditions evoke impressions of surfaces oriented in depth. These impressions have been studied by measuring the slants of perceived surfaces, with probes (rotating arrowheads) designed to respect the distinctive character of depicted scenes. Converging arguments indicated that the perceived orientation of the probes was near theoretical values. A series of experiments showed that subjects formed well-defined impressions of depicted surface orientation. The literature suggests that perceived objects might be ‘flattened’, but that was not the general rule. Instead, both mean slant and uncertainty fitted models in which slant estimates are derived in a relatively straightforward way from local relations in the picture. Simplifying pictures tended to make orientation estimates less certain, particularly away from the natural anchor points (vertical and horizontal). The shape of the object affected all aspects of the observed-object/percept relationship. Individual differences were large, and suggest that different individuals used different relationships as a basis for their estimates. Overall, data suggest that everyday picture perception is strongly selective and weakly integrative. In particular, depicted slant is estimated by finding a picture feature which will be strongly related to it if the object contains a particular regularity, not by additive integration of evidence from multiple directly and indirectly relevant sources.
Anisotropy in Haptic Curvature and Shape Perception
Authors: Pont Sylvia C , Kappers Astrid M L , Koenderink Jan J
Published: January 2007

An investigation was undertaken into whether haptic comparison of curvature and of shape is influenced by the length/width ratio of the hand. For this purpose three experiments were conducted to test the curvature matching of curved strips (experiment 1), the curvature matching of cylindrically curved hand-sized surfaces (experiment 2), and the shape discrimination of elliptically curved hand-sized surfaces (experiment 3). The orientation of the stimuli with respect to the fingers was varied. The results of the two matching experiments showed that a given curvature is judged to be more curved when touched along the fingers than when touched across the fingers. The phenomenal flatness along and across the fingers was found to be different and subject dependent. The results of the shape-discrimination experiment showed that the orientation of ellipsoidal surfaces influences the judgments of the shapes of these surfaces. This influence could be predicted on the basis of results of the second matching experiment. It is concluded that similar mechanisms underlie the (anisotropic) perception of curvature and shape. For the major part the trends in the results can be explained by the length/width ratio of the hand and the phenomenal flatnesses.
Attentional Modulation in Perception of Visual Motion Events
Authors: Watanabe Katsumi , Shimojo Shinsuke
Published: January 2007

Identical visual targets moving across each other with equal and constant speed can be perceived either to bounce off or to stream through each other. This bistable motion perception has been studied mostly in the context of motion integration. Since the perception of most ambiguous motion is affected by attention, there is the possibility of attentional modulation occurring in this case as well. We investigated whether distraction of attention from the moving targets would alter the relative frequency of each percept. During the observation of the streaming/bouncing motion event in the peripheral visual field, visual attention was disrupted by an abrupt presentation of a visual distractor at various timings and locations (experiment 1; exogenous distraction of attention) or by the demand of an additional discrimination task (experiments 2 and 3; endogenous distraction of attention). Both types of distractions of attention increased the frequency of the bouncing percept and decreased that of the streaming percept. These results suggest that attention may facilitate the perception of object motion as continuing in the same direction as in the past.
Mapping the Mental Space of Rectangles
Authors: Feldman Jacob , Richards Whitman
Published: January 2007

The cognitive structure of a shape space—the space of rectangles—is explored by a nonmetric scaling technique. Our experiment was designed to extract the major transformational paths or ‘modes’ that characterize the mental shape space. Earlier studies of rectangle similarities using multidimensional scaling have provided conflicting evidence about whether the coordinate system of the mental rectangle space is based on height and width or on area and shape (ie aspect ratio). Our study reveals shape to be the single dominant factor. We suspected that earlier evidence for a height – width parameterization might have been due to the presentation of rectangles upright in a pseudo-gravitational coordinate system (whereas our rectangles are randomly rotated). In a control experiment with upright (vertical or horizontal) rectangles, the heavy bias towards shape preservation was still the dominant mode. In addition, however, a secondary bias towards change of height or width emerged, exactly following the pattern expected from the biasing change in context. This finding established a concrete path by which context and frame can influence the way shape is represented. The relevance of these findings to the cognitive organization of more complex shape spaces is discussed.
Apparent Contraction of Edge Angles
Authors: Kitaoka Akiyoshi
Published: January 2007

The corner effect, the Münsterberg illusion, and the Cafe Wall illusion are explained by a model postulating that the corner effect is an orientation illusion specific to corner edges and that the perceived orientations of these edges are shifted toward angle contraction. It is also assumed that the effect is greatest when the corner edges show the same or similar edge contrast at the corner. This model yields three new types of illusions: the ‘checkered illusion’, the ‘illusion of shifted gradations’, and the ‘illusion of striped cords’. Each of them gives many variations making a three-dimensional impression.
The Moon Tilt Illusion
Authors: Schölkopf Bernhard
Published: January 2007

Besides the familiar moon illusion [eg Hershenson, 1989 The Moon Illusion (Hillsdale, NJ: Lawrence Erlbaum Associates)], wherein the moon appears bigger when it is close to the horizon, there is a less known illusion which causes the moon's illuminated side to appear turned away from the direction of the sun. An experiment documenting the effect is described, and a possible explanation is put forward.
Seeing the Disappearance of Unseen Objects
Authors: Mitroff Stephen R , Scholl Brian J
Published: January 2007

Because of the massive amount of incoming visual information, perception is fundamentally selective. We are aware of only a small subset of our visual input at any given moment, and a great deal of activity can occur right in front of our eyes without reaching awareness. While previous work has shown that even salient visual objects can go unseen, here we demonstrate the opposite pattern, wherein observers perceive stimuli which are not physically present. In particular, we show in two motion-induced blindness experiments that unseen objects can momentarily reenter awareness when they physically disappear: in some situations, you can see the disappearance of something you can't see. Moreover, when a stimulus changes outside of awareness in this situation and then physically disappears, observers momentarily see the altered version—thus perceiving properties of an object that they had never seen before, after that object is already gone. This phenomenon of ‘perceptual reentry’ yields new insights into the relationship between visual memory and conscious awareness.
Large-scale phosphorylation analysis of mouse liver
Authors: Villén Judit , Beausoleil Sean A. , Gerber Scott A. , Gygi Steven P.
Published: January 2007

Protein phosphorylation is a complex network of signaling and regulatory events that affects virtually every cellular process. Our understanding of the nature of this network as a whole remains limited, largely because of an array of technical challenges in the isolation and high-throughput sequencing of phosphorylated species. In the present work, we demonstrate that a combination of tandem phosphopeptide enrichment methods, high performance MS, and optimized database search/data filtering strategies is a powerful tool for surveying the phosphoproteome. Using our integrated analytical platform, we report the identification of 5,635 nonredundant phosphorylation sites from 2,328 proteins from mouse liver. From this list of sites, we extracted both novel and known motifs for specific Ser/Thr kinases including a “dipolar” motif. We also found that C-terminal phosphorylation was more frequent than at any other location and that the distribution of potential kinases for these sites was unique. Finally, we identified double phosphorylation motifs that may be involved in ordered phosphorylation.
Interaction of the Wiskott–Aldrich syndrome protein with sorting nexin 9 is required for CD28 endocytosis and cosignaling in T cells
Authors: Badour Karen , McGavin Mary K. H. , Zhang Jinyi , Freeman Spencer , Vieira Claudia , Filipp Dominik , Julius Michael , Mills Gordon B. , Siminovitch Katherine A.
Published: January 2007

The Wiskott–Aldrich syndrome protein (WASp) plays a major role in coupling T cell antigen receptor (TCR) stimulation to induction of actin cytoskeletal changes required for T cell activation. Here, we report that WASp inducibly binds the sorting nexin 9 (SNX9) in T cells and that WASp, SNX9, p85, and CD28 colocalize within clathrin-containing endocytic vesicles after TCR/CD28 costimulation. SNX9, implicated in clathrin-mediated endocytosis, binds WASp via its SH3 domain and uses its PX domain to interact with the phosphoinositol 3-kinase regulatory subunit p85 and product, phosphoinositol (3,4,5)P3. The data reveal ligation-induced CD28 endocytosis to be clathrin- and phosphoinositol 3-kinase-dependent and TCR/CD28-evoked CD28 internalization and NFAT activation to be markedly enhanced by SNX9 overexpression, but severely impaired by expression of an SNX9 mutant (SNX9ΔPX) lacking p85-binding capacity. CD28 endocytosis and CD28-evoked actin polymerization also are impaired in WASp-deficient T cells. These findings suggest that SNX9 couples WASp to p85 and CD28 so as to link CD28 engagement to its internalization and to WASp-mediated actin remodeling required for CD28 cosignaling. Thus, the WASp/SNX9/p85/CD28 complex enables a unique interface of endocytic, actin polymerizing, and signal transduction pathways required for CD28-mediated T cell costimulation.
Cdc37 has distinct roles in protein kinase quality control that protect nascent chains from degradation and promote posttranslational maturation
Authors: Mandal Atin K. , Lee Paul , Chen Jennifer A. , Nillegoda Nadinath , Heller Alana , DiStasio Susan , Oen Handy , Victor Jacob , Nair Devi M. , Brodsky Jeffrey L. , Caplan Avrom J.
Published: January 2007

Cdc37 is a molecular chaperone that functions with Hsp90 to promote protein kinase folding. Analysis of 65 Saccharomyces cerevisiae protein kinases (∼50% of the kinome) in a cdc37 mutant strain showed that 51 had decreased abundance compared with levels in the wild-type strain. Several lipid kinases also accumulated in reduced amounts in the cdc37 mutant strain. Results from our pulse-labeling studies showed that Cdc37 protects nascent kinase chains from rapid degradation shortly after synthesis. This degradation phenotype was suppressed when cdc37 mutant cells were grown at reduced temperatures, although this did not lead to a full restoration of kinase activity. We propose that Cdc37 functions at distinct steps in kinase biogenesis that involves protecting nascent chains from rapid degradation followed by its folding function in association with Hsp90. Our studies demonstrate that Cdc37 has a general role in kinome biogenesis.
FAK is required for axonal sorting by Schwann cells
Authors: Grove Matthew , Komiyama Noboru H. , Nave Klaus-Armin , Grant Seth G. , Sherman Diane L. , Brophy Peter J.
Published: January 2007

Signaling by laminins and axonal neuregulin has been implicated in regulating axon sorting by myelin-forming Schwann cells. However, the signal transduction mechanisms are unknown. Focal adhesion kinase (FAK) has been linked to α6β1 integrin and ErbB receptor signaling, and we show that myelination by Schwann cells lacking FAK is severely impaired. Mutant Schwann cells could interdigitate between axon bundles, indicating that FAK signaling was not required for process extension. However, Schwann cell FAK was required to stimulate cell proliferation, suggesting that amyelination was caused by insufficient Schwann cells. ErbB2 receptor and AKT were robustly phosphorylated in mutant Schwann cells, indicating that neuregulin signaling from axons was unimpaired. These findings demonstrate the vital relationship between axon defasciculation and Schwann cell number and show the importance of FAK in regulating cell proliferation in the developing nervous system.
Lipoxins and aspirin-triggered lipoxin inhibit inflammatory pain processing
Authors: Svensson Camilla I. , Zattoni Michela , Serhan Charles N.
Published: January 2007

Inflammatory conditions can lead to debilitating and persistent pain. This hyperalgesia reflects sensitization of peripheral terminals and facilitation of pain signaling at the spinal level. Studies of peripheral systems show that tissue injury triggers not only inflammation but also a well-orchestrated series of events that leads to reversal of the inflammatory state. In this regard, lipoxins represent a unique class of lipid mediators that promote resolution of inflammation. The antiinflammatory role of peripheral lipoxins raises the hypothesis that similar neuraxial systems may also down-regulate injury-induced spinal facilitation of pain processing. We report that the lipoxin A4 receptor is expressed on spinal astrocytes both in vivo and in vitro and that spinal delivery of lipoxin A4, as well as stable analogues, attenuates inflammation-induced pain. Furthermore, activation of extracellular signal-regulated kinase and c-Jun N-terminal kinase in astrocytes, which has been indicated to play an important role in spinal pain processing, was attenuated in the presence of lipoxins. This linkage opens the possibility that lipoxins regulate spinal nociceptive processing though their actions upon astrocytic activation. Targeting mechanisms that counterregulate the spinal consequences of persistent peripheral inflammation provide a novel endogenous mechanism by which chronic pain may be controlled.
Thymic stromal lymphopoietin is released by human epithelial cells in response to microbes, trauma, or inflammation and potently activates mast cells
Authors: Allakhverdi Zoulfia , Comeau Michael R. , Jessup Heidi K. , Yoon Bo-Rin Park , Brewer Avery , Chartier Suzanne , Paquette Nicole , Ziegler Steven F. , Sarfati Marika , Delespesse Guy
Published: January 2007

Compelling evidence suggests that the epithelial cell–derived cytokine thymic stromal lymphopoietin (TSLP) may initiate asthma or atopic dermatitis through a dendritic cell–mediated T helper (Th)2 response. Here, we describe how TSLP might initiate and aggravate allergic inflammation in the absence of T lymphocytes and immunoglobulin E antibodies via the innate immune system. We show that TSLP, synergistically with interleukin 1 and tumor necrosis factor, stimulates the production of high levels of Th2 cytokines by human mast cells (MCs). We next report that TSLP is released by primary epithelial cells in response to certain microbial products, physical injury, or inflammatory cytokines. Direct epithelial cell–mediated, TSLP-dependent activation of MCs may play a central role in “intrinsic” forms of atopic diseases and explain the aggravating role of infection and scratching in these diseases.
Appearance Potential Spectra of the Alkaline-earth Metals Ca, Sr and Ba
Authors: J Kanski  , P O Nilsson
Published: January 2007

An apparatus for measurements of appearance potential spectra in the 20-2 000 eV and 10-10torr range has been constructed and tested. The total resolution is found to be about 0.8 eV. Spectra for different core levels of Ca, Sr, and Ba as well as of their oxides have been measured. The data are discussed in terms of localized, unoccupied electronic states. Comparisons are made with other types of experimental data and with models involving the (local) density of states. For Ba complications arise due to the very localized 4fstates, but the results can be explained if the whole two-electron-one-hole system is taken into account.
Zeeman Effect of the 6 476 Å Mixed Multipole Line of Bismuth
Authors: L Augustyniak  , J Heldt  , J Bronowski
Published: January 2007

The Zeeman effect of the 6 476 Å mixed multipole (or so-called forbidden) line was studied with a Fabry-Perot interferometer and a tri-prism spectrograph in magnetic fields of 1.3, 1.5, 1.7 and 2.0 kG. The relative intensities of the ΔM = ± 1 and ΔM = 0, ± 2 transitions for longitudinal and transverse directions of observations are calculated as functions of the external magnetic field and electric-quadrupole admixture. The differences between the relative intensities of ΔM = ± 1 Zeeman patterns observed in two directions are due to the interference of the magnetic-dipole and the electric-quadrupole radiation. A comparison of the computed and experimental intensities shows that this line has predominantly a magnetic-dipole character with the percentage of the electric-quadrupole radiation in this line being about 18 ± 4.5%. This result is in good agreement with the value obtained by Garstang.
On the Spin-orbit Coupling in the Ground States of AsH and AsD
Authors: B Lindgren
Published: January 2007

The3Σ-ground states of AsH and AsD have been investigated in order to study theJ-dependence in the spin-orbit coupling. At least for AsD such aJ-dependence is observed.
Ethene and the Chloroethenes Studied by ESCA
Authors: A Berndtsson  , E Basilier  , U Gelius  , J Hedman  , M Klasson  , R Nilsson  , C Nordling  , S Svensson
Published: January 2007

ESCA studies have been made of core and valence electrons in ethene and all the chloroethenes, using an instrument incorporating X-ray monochromatization. The orbitals are assigned according to calculated intensities and Extended Hückel type (EHT) calculations, as well as previously available data. Intensities are calculated from a model based on net atomic EHT populations and are found to agree well with experimental results. Also, CNDO calculations were performed.
The Optical Spectra of β' Brass and the Heusler Alloys Cu2MnAl and Cu2MnIn
Authors: H P Myers  , L Linder
Published: January 2007

Specimens of β' brass, Cu2MnAl and Cu2MnIn were studied by ellipsometry. Measurements were made in air. The brass spectrum is in general agreement with theoretical band structure calculations. Spectra for the two Heusler alloys are similar but significantly different from that of β' brass which is attributed to the absence or suppression of conduction band transitions in the Heusler alloys due to the presence of emptydstates associated with the manganese atoms.
Predictions of a Regge Pole Model with Factorized Residues for the Reaction pp̄ → Δ
Authors: B O Enflo  , I Frick
Published: January 2007

Relations among the resonance decay parameters in the reaction pp̄ → Δ are given, which hold for a Regge pole model with factorized residues. Those combinations of the residues are given, which are measurable in an unpolarized experiment.
Search for Low-spin Negative Parity States in97Mo and99Mo
Authors: W Dietrich  , G Ch Madueme  , L Westerberg  , A Bäcklin
Published: January 2007

By means of in-beam gamma-ray and conversion electron spectroscopy spin and parity has been assigned to states of97,99Mo observed in the96Mo(d,pγ)97Mo and98Mo(d,pγ)99Mo reaction, respectively. The data indicate that no low-spin negative parity states are likely to exist below ∼ 1 Mev.
Hyperfine Interaction, Zeeman and Stark Effects for Excited States in Potassium
Authors: G Belin  , L Holmgren  , I Lindgren  , S Svanberg
Published: January 2007

Using the optical double resonance and level crossing methods, properties of several excitedS,P, andDstates in39K were studied. TheSandDstates were populated using stepwise excitation with the firstPstate as an intermediate level. An rf lamp and a CW dye laser were used in the first and second excitation steps, respectively. The studiedPstates were populated in the cascade decay of states, excited with the laser. The following results for the magnetic depole interaction constant a, the LandégJfactor, and the tensor polarizability α2were obtained for the studied states:

72S1/2: a = 10.78(5) MHz,gJ= 2.0020(10);

82S1/2: a = 5.99(8) MHz,gJ= 2.0028(12);

62P1/2: a = 4.05(7) MHz,gJ= 0.6663(4);

62P3/2: a = 0.89(5) MHz,gJ= 1.3337(8);

72P1/2: a = 2.18(5) MHz,gJ= 0.6659(6);

72P3/2: a = 0.49(4) MHz,gJ= 1.3336(8);

52D3/2: |a| = 0.44(10) MHz,gJ= 0.7997(7), |α2| = 9.64(45) MHz/(kV)/cm)2;

52D5/2: |a| = 0.24(7) MHz,gJ= 1.2004(10), |α2| = 13.4(7) MHz/(kV)/cm)2;

62D3/2: |a| = 0.2(2) MHz,gJ= 0.7997(14), |α2| = 33.8(1.7) MHz/(kV)/cm)2;

62D5/2: |a| = 0.1(1) MHz,gJ= 1.2013(20), |α2| = 47.6(2.4) MHz/(kV)/cm)2.

Theoretical values for the magnetic dipole interaction constant have been obtained using a limited many-body perturbation expansion. The Polarization effect, which is due to single excitations from the restricted Hartree-Fock model, is included to all orders, while the true correlation effect is omitted. The results are compared with the experimental values, and the agreement is found to be quite good. For theSandPstates the polarization effect is of the order of 10-20%, and it is responsible for roughly half of the deviation of the Hartree-Fock values from experiment. For theDstates, on the other hand, the effects are much more drastic. The sign of theafactors has not been measured. The perturbative calculation yields positive values for all2D3/2states and negative values for all2D5/2 states. The theoretical magnitudes are in agreement with the observed ones.
Large-scale influences in near-wall turbulence
Authors: Hutchins Nicholas , Marusic Ivan
Published: January 2007

Hot-wire data acquired in a high Reynolds number facility are used to illustrate the need for adequate scale separation when considering the coherent structure in wall-bounded turbulence. It is found that a large-scale motion in the log region becomes increasingly comparable in energy to the near-wall cycle as the Reynolds number increases. Through decomposition of fluctuating velocity signals, it is shown that this large-scale motion has a distinct modulating influence on the small-scale energy (akin to amplitude modulation). Reassessment of DNS data, in light of these results, shows similar trends, with the rate and intensity of production due to the near-wall cycle subject to a modulating influence from the largest-scale motions.
The need for stochastic replication of ecological neural networks
Authors: Tosh Colin R , Ruxton Graeme D
Published: January 2007

Artificial neural networks are becoming increasingly popular as predictive statistical tools in ecosystem ecology and as models of signal processing in behavioural and evolutionary ecology. We demonstrate here that a commonly used network in ecology, the three-layer feed-forward network, trained with the backpropagation algorithm, can be extremely sensitive to the stochastic variation in training data that results from random sampling of the same underlying statistical distribution, with networks converging to several distinct predictive states. Using a random walk procedure to sample error–weight space, and Sammon dimensional reduction of weight arrays, we demonstrate that these different predictive states are not artefactual, due to local minima, but lie at the base of major error troughs in the error–weight surface. We further demonstrate that various gross weight compositions can produce the same predictive state, suggesting the analogy of weight space as a ‘patchwork’ of multiple predictive states. Our results argue for increased inclusion of stochastic training replication and analysis into ecological and behavioural applications of artificial neural networks.
Haemoperfused liver as an ex vivo model for organ invasion of Candida albicans
Authors: Thewes Sascha , Reed Hilde-Kristin , Grosse-Siestrup Christian , Groneberg David A. , Meissler Michael , Schaller Martin , Hube Bernhard
Published: January 2007

To study invasion of the human fungal pathogen Candida albicans, several infection models have been established. This study describes the successful establishment of an ex vivo haemoperfused liver as a model to study invasion of C. albicans. Perfused organs from pigs could be kept functional for up to 12 h. By comparing a non-invasive and invasive strain of C. albicans and by following a time course of invasion, it was shown that the invasion process in the perfused liver infection model is very similar to the in vivo situation after intraperitoneal infection of mice. The advantage of this set-up compared with other models of invasion is discussed.
A PCR approach to determine the distribution of toxin genes in closely related Clostridium species: Clostridium botulinum type C and D neurotoxins and C2 toxin, and Clostridium novyi α toxin
Authors: Heffron Ann , Poxton Ian R.
Published: January 2007

The closely relatedClostridium novyiandClostridium botulinumtypes C and D are of current interest because of their association with serious infections in injecting drug users (C. novyitype A) and equine and feline dysautonomias (C. botulinumtypes C/D). The species are defined by the major toxins they produce: theαtoxin ofC. novyi, and the type C and D neurotoxins ofC. botulinum(BoNT/C and BoNT/D). The other major toxin produced by this group, and previously thought to be restricted to the botulinum types, is the chromosomally encoded C2 – a binary toxin consisting of two components, I and II. In the current study 44 of these clostridia from the authors' culture collection were investigated – most of which had been identified previously by conventional biochemical tests as ‘C. novyitype A’. The aim was to check the distribution of toxin genes by PCR to see if the identities were consistent with the genes carried, and to ascertain if the C2 gene was only found in authenticC. botulinumstrains. Several combinations of the species-defining genes and the two components of the C2 genes were detected. Only the authentic BoNT/C- and BoNT/D-positiveC. botulinumstrains and one of two non-neurotoxic variants of type C carried genes for both components of the C2 toxin. Of the remaining 40C. novyitype A-like strains, the gene for theαtoxin was found in 22, with 19 of these also possessing the gene for component I (16) or component II (3) but not both. In theαtoxin-negative strains (22), both of the C2 genes were detected in 5 strains (3C. botulinum), with component I in 11 strains and neither gene in 6 strains.
Species distribution and antifungal susceptibility of Candida bloodstream isolates in Kuwait: a 10-year study
Authors: Mokaddas Eiman M. , Al-Sweih Noura A. , Khan Zia U.
Published: January 2007

Bloodstream infections due to Candida species are important complications in severely ill hospitalized patients. This study presents data on species distribution and antifungal susceptibility profiles of Candida bloodstream isolates obtained from Kuwait during a 10-year period. All the bloodstream isolates were identified to species level by the germ tube test and carbohydrate assimilation profile using the VITEK 2 yeast identification system. Using E-test strips for amphotericin B, fluconazole, 5-flucytosine and voriconazole, MICs were determined on RPMI agar supplemented with 2 % glucose. The MIC breakpoints for resistance were based on Clinical and Laboratory Standards Institute criteria or those published by reference laboratories, and were as follows: amphotericin B, >1 μg ml−1; fluconazole, ⩾64 μg ml−1; 5-flucytosine, ⩾32 μg ml−1; and voriconazole, 4 μg ml−1. In all, 607 bloodstream yeast isolates were obtained over the past 10 years in Kuwait. Candida albicans was the predominant species (39.5 %), followed by Candida parapsilosis (30.6 %), Candida tropicalis (12.4 %), Candida glabrata (5.6 %) and Candida krusei (1.6 %). All C. albicans, C. tropicalis and C. glabrata isolates were susceptible to amphotericin B. Of 186 isolates of C. parapsilosis tested, only four (2 %) exhibited an MIC for amphotericin B of >1 μg ml−1. Resistance to fluconazole was observed in nine (3.8 %) C. albicans isolates, two (5.8 %) C. glabrata isolates and four (40 %) C. krusei isolates. Resistance to 5-flucytosine was observed in two (0.8 %) C. albicans isolates, seven (9.3 %) C. tropicalis isolates, three (1.6 %) C. parapsilosis isolates and all ten (100 %) C. krusei isolates. All the isolates of C. albicans, C. tropicalis, C. parapsilosis, C. glabrata and C. krusei were susceptible to voriconazole, including those resistant to fluconazole. Although amphotericin B and fluconazole are widely used in clinical practice in Kuwait, resistance to these drugs remained low.
Molecular mechanisms of antimony resistance in Leishmania
Authors: Ashutosh  , Sundar Shyam , Goyal Neena
Published: January 2007

Leishmaniasis causes significant morbidity and mortality worldwide. The disease is endemic in developing countries of tropical regions, and in recent years economic globalization and increased travel have extended its reach to people in developed countries. In the absence of effective vaccines and vector-control measures, the main line of defence against the disease is chemotherapy. Organic pentavalent antimonials [Sb(V)] have been the first-line drugs for the treatment of leishmaniasis for the last six decades, and clinical resistance to these drugs has emerged as a primary obstacle to successful treatment and control. A multiplicity of resistance mechanisms have been described in resistantLeishmaniamutants developedin vitroby stepwise increases of the concentration of either antimony [Sb(III)] or the related metal arsenic [As(III)], the most prevalent mechanism being upregulated Sb(III) detoxification and sequestration. With the availability of resistant field isolates, it has now become possible to elucidate mechanisms of clinical resistance. The present review describes the mechanisms of antimony resistance inLeishmaniaand highlights the links between previous hypotheses and current developments in field studies. Unravelling the molecular mechanisms of clinical resistance could allow the prevention and circumvention of resistance, as well as rational drug design for the treatment of drug-resistantLeishmania.
Design of a functionally equivalent nonglycosylated analog of the glycopeptide antibiotic formaecin I
Authors: Kaur Kanwal J. , Pandey Shashank , Salunke Dinakar M.
Published: January 2007

Various nonglycosylated analogs were designed in order to explore the role of glycosylation in formaecin I, an antibacterial glycopeptide of insect origin. The functional behavior of a designed nonglycosylated analog (P7,endo P8a,ΔT11)formaecin I was found to be similar to that of native glycosylated peptide. Both the peptides showed similar antibacterial activities against Escherichia coli and Salmonella strains. The designed nonglycosylated analog (P7,endo P8a,ΔT11)formaecin I has low binding affinity to LPS identical to that of native glycopeptide, formaecin I. Both the peptides have similar killing kinetics and are nontoxic to erythrocytes. Formaecin I and designed nonglycosylated (P7,endo P8a,ΔT11)formaecin I have no definite conformational features associated with them. The glycosylated residue of threonine in formaecin I and proline residues in designed peptide [(P7,endo P8a,ΔT11)formaecin I], possibly help in stabilizing the correct conformation that facilitates presentation of the peptide to its receptor. It is evident that a functionally equivalent nonglycosylated analog of native glycosylated antibacterial peptide can be designed by strategically modifying the sequence.
Diagnosis of Parietaria judaica pollen allergy using natural and recombinant Par j 1 and Par j 2 allergens
Authors: González‐Rioja R. , Ferrer A. , Arilla M.C. , Ibarrola I. , Viguera A.R. , Andreu C. , Martínez A. , Asturias J.A.
Published: January 2007

Background
Parietaria judaica pollen is one of the main causes of allergic diseases in the Mediterranean area and contains two major allergens, called Par j 1 and Par j 2.

Objective
To evaluate the diagnostic potential of natural and recombinant forms of Par j 1 and Par j 2 in comparison with standardized P. judaica pollen extract.

Methods
Thirty patients allergic to P. judaica pollen and 15 control patients were investigated. Skin prick tests and determination of specific IgE levels were performed with commercial P. judaica extract, natural Par j 1 and Par j 2, and recombinant forms of both allergens expressed in P. pastoris.

Results
The whole group of patients with allergy to P. judaica had a positive skin test reaction to purified nPar j 1–Par j 2 and rPar j 2 at 5 μg/mL, and no false‐positive reactions were detected. Natural and recombinant Par j 1 and Par j 2 showed no significantly different responses in skin tests compared with P. judaica extract. A high correlation was found between the serum‐specific IgE levels to P. judaica extract vs. natural (R=0.996; P<0.001) and recombinant allergens (R=0.887 and 0.982 for rPar j 1 and rPar j 2, respectively; P<0.001). rPar j 2 displayed a 100% sensitivity and specificity among P. judaica‐allergic patients.

Conclusions
In vivo and in vitro diagnosis of P. judaica pollen allergy could be simplified using rPar j 2. This protein showed comparable IgE response and skin prick reactivity with those produced by P. judaica pollen extract.
Skin prick‐test reactivity to aeroallergens and allergic symptoms in an urban population of central Italy: a longitudinal study
Authors: Dottorini M. L. , Bruni B. , Peccini F. , Bottini P. , Pini L. , Donato F. , Casucci G. , Tantucci C.
Published: January 2007

Background
Cross‐sectional studies report an increasing prevalence of allergic diseases, such as rhinitis and asthma. Not thoroughly known, instead, is the natural history of allergic sensitization and the progress of the allergic disease‐related symptoms.

Aim
The purpose of this study was to evaluate longitudinally the skin reactivity for the most common aeroallergens and the allergic symptoms in an urban population living in Perugia, a town of central Italy with a low‐level of air pollution exposure.

Methods
In the 1998–1999 period 788 subjects were tested for skin reactivity to a panel of aeroallergens and underwent the administration of a questionnaire. These same subjects were part of a cohort of 1200 subjects who participated in a previous epidemiological study performed in 1984–1985 using the same tools. Subjects were aged between 14 and 64 years at the time of the first survey.

Results
In the present survey 196 subjects (24.9%) had skin reactivity to at least one aeroallergen, while in the previous survey 143 subjects (18.1%) had skin prick‐test reactivity. The increase of the skin reactivity between the two observations was highly significant (P<0.001) and was mainly observed in subjects <40‐years old. The greatest increment in skin reactivity was seen to Dermatophagoides pteronyssinus (house dust mite) allergen. Data obtained from questionnaires showed that subjects who declared allergic symptoms increased from 341 (43.3%) to 380 (48.2%). However, the increase was significant (P<0.01) only in subjects who had a positive association between allergic symptoms and prick‐test reactivity and was greater for rhino‐conjunctivitis than for asthma‐related symptoms.

Conclusions
In a cohort of urban population of the centre of Italy, exposed to a low and stable level of air pollution, the sensitization to common aeroallergens increased with time, mostly in people <40‐years of age. The greatest increment was found for indoor allergens such as Dermatophagoides pteronysimus. A significant increase in allergic symptoms, mainly related to rhino‐conjunctivitis, was observed only in the presence of positive prick test.
Smear cytology in the intra‐operative assessment of periodontoid pseudotumour of the craniocervical junction
Authors: Galloway M. , Amin A. , Casey A. , Crockard A. , Revesz T.
Published: January 2007

Objective:  Periodontoid pseudotumours are lesions of presumed degenerative aetiology which typically occur in elderly patients with cervical myelopathy. The clinical and radiological differential diagnosis includes neoplastic and inflammatory lesions, and the exclusion of such lesions may be of value in the intra‐operative management of the patient. This audit aimed to examine the value of intra‐operative smear cytology in the management of this condition.

Methods:  The intra‐operative smear cytological features of four cases of periodontoid pseudotumour were reviewed.

Results:  In each case the intra‐operative cytological interpretation was in keeping with a non‐neoplastic and non‐inflammatory process.

Conclusion:  These results suggest that intra‐operative smear cytology can provide information on the value in the intra‐operative management of patients with this lesion.
Opportunism at work: habitat predictability affects reproductive readiness in free‐living zebra finches
Authors: PERFITO NICOLE , ZANN RICHARD A. , BENTLEY GEORGE E. , HAU MICHAELA
Published: January 2007

Opportunistic breeding (i.e. breeding whenever favourable conditions occur, regardless of interval or periodicity) is a strategy often adopted by animals breeding in habitats where food resources important for offspring survival are unpredictable.

One putative adaptation for this breeding strategy is the maintenance of a partially activated reproductive system year‐round. Breeding readiness is assumed to be the default state and reproduction is therefore suppressed only when environmental conditions become inhibitory.

We tested this assumption in an opportunistic archetype, the Australian zebra finchTaeniopygia guttata, by comparing reproductive activation and suppression in free‐living zebra finches in two climatically different habitats: (1) an unpredictable habitat of arid central Australia, where breeding is closely tied to aperiodic rainfall and can occur during any month of the year, and (2) a more predictably seasonal habitat in southern Australia, where breeding occurs during approximately the same months each year. We quantified reproductive activation by measuring gonad size and circulating gonadotrophin concentration during the breeding and nonbreeding seasons in the predictable habitat and within a nonbreeding period during drought in the unpredictable habitat.

We found reproductive readiness changed consistently between the breeding and nonbreeding state in the predictable habitat, but more nonbreeding birds in the unpredictable habitat maintained an activated reproductive system even though they had poorer body condition. We found no evidence for suppression of reproductive activity by stress hormones (i.e. elevated glucocorticoids). Furthermore, birds were able to activate the reproductive axis quickly when removed from inhibitory field conditions and responded equally well to various stimulatory cues.
Robustness of factor assays following cordocentesis in the prenatal diagnosis of haemophilia and other bleeding disorders
Authors: SHETTY S. , GHOSH K.
Published: January 2007

Summary.  Prenatal diagnosis is the generally accepted option for genetic disorders including haemophilias and other bleeding disorders. Cord blood analysis between 17.4 and 20.6 weeks of gestation was performed in 172 confirmed carriers belonging to families of haemophilia A, haemophilia B, von Willebrand disease (VWD), factor VII and X deficiency; 133 were carriers for haemophilia A, 30 for haemophilia B, six for type 3 VWD, two for FX deficiency and one for FVII deficiency. The approach to the cord was either transabdominal or transamniotic. The volume of blood collected varied between 1 and 2 mL. In case of haemophilias, the diagnosis was offered by factor VIII/IX:C activity and antigen assays wherever required. In case of VWD, the diagnosis was based on von Willebrand factor antigen assays as detected by ELISA along with FVIII:C assay while in cases of FVII and FX deficiency, the diagnosis was based on FVII:C and FX:C respectively. The factor levels were compared with the normal range established in the laboratory for different coagulation factors between 18 and 21 weeks of gestation in women tested for other haematological disorders. Only in two cases, the procedure had to be repeated for reasons of extensive maternal contamination. All the deliveries have been followed up and the diagnoses reconfirmed by repeat clotting factor assays and DNA analysis whenever informative. Simple precautions like collection of fetal blood samples in smaller volumes in separate tubes, assaying multiple coagulation factors in the fetal blood samples helped us to offer diagnoses in all the women analysed. No fetal death or abortion was reported following the procedure. We suggest that accurate fetal blood sampling is a safe technique for the diagnosis of many of the bleeding disorders in places where genetic diagnostic services are not available.
Changes in the Expression of Corticotrophin‐Releasing Hormone, Mineralocorticoid Receptor and Glucocorticoid Receptor mRNAs in the Hypothalamic Paraventricular Nucleus Induced by Fornix Transection and Adrenalectomy
Authors: Han F. , Ozawa H. , Matsuda K.‐I. , Lu H. , De Kloet E. R. , Kawata M.
Published: January 2007

The paraventricular nucleus (PVN) in the hypothalamus receives inputs from the hippocampus. The present study explored the influence of the hippocampus on genes mediating glucocorticoid feedback in the PVN. Accordingly, the expression of mRNAs for corticotrophin‐releasing hormone (CRH), the mineralocorticoid receptor (MR) and the glucocorticoid receptor (GR) in the PVN was examined by in situ hybridisation in rats subjected to transection of the fornix. Significant increases in CRH, MR and GR mRNAs were observed in the parvocellular PVN after fornix transection (FT). FT‐animals subjected to adrenalectomy also showed an increase in the number of cells positive for CRH and GR mRNAs. CRH, MR and GR mRNA expression was also increased by bilateral adrenalectomy, and GR mRNA expression was further enhanced in the parvocellular PVN of the FT transected animals. However, no such changes were evident in the magnocellular PVN. These results suggest that the input from the hippocampus to the PVN, particularly to its parvocellular region, has distinct and differential inhibitory effects on the expression of MR, GR and CRH mRNAs that may operate independently from the feedback actions of corticosterone.
Spatial analysis of nuclear and cytoplasmic DNA diversity in wild sea beet (Beta vulgarisssp.maritima) populations: do marine currents shape the genetic structure?
Authors: FIEVET VIRGIL , TOUZET PASCAL , ARNAUD JEAN‐FRANÇOIS , CUGUEN JOËL
Published: January 2007

Patterns of seed dispersal in the wild sea beet (Beta vulgarisssp.maritima) are predicted to be influenced by marine currents because populations are widely distributed along the European Atlantic coast. We investigated the potential influence of marine currents on the pattern of spatial genetic structuring in natural populations of sea beet. Populations were located along the French coasts of the Anglo‐Norman gulf that features peculiar marine currents in the Channel.Thirty‐three populations were sampled, among which 23 were continental and 10 were insular populations located in Jersey, Guernsey and Chausey, for a total of 1224 plants genotyped. To validate the coastal topography influence and the possibility of marine current orientated gene flow on the genetic features of sea beet populations, we assessed patterns of genetic structuring of cytoplasmic and nuclear diversity by: (i) searching for an isolation‐by‐distance (IBD) pattern using spatial autocorrelation tools; (ii) using the Monmonier algorithm to identify genetic boundaries in the area studied; and (iii) performing assignment tests that are based on multilocus genotype information to ascertain population membership of individuals. Our results showed a highly contrasted cytoplasmic and nuclear genetic differentiation and highlighted the peculiar situation of island populations. Beyond a classical isolation‐by‐distance due to short‐range dispersal, genetic barriers fitting the orientation of marine currents were clearly identified. This suggests the occurrence of long‐distance seed dispersal events and an asymmetrical gene flow separating the eastern and western part of the Anglo‐Norman gulf.
Natural variation in the genetic architecture of a host–parasite interaction in the bumblebee Bombus terrestris
Authors: WILFERT L. , GADAU J. , BAER B. , SCHMID‐HEMPEL P.
Published: January 2007

The genetic architecture of fitness‐relevant traits in natural populations is a topic that has remained almost untouched by quantitative genetics. Given the importance of parasitism for the host's fitness, we used QTL mapping to study the genetic architecture of traits relevant for host–parasite interactions in the trypanosome parasite, Crithidia bombi and its host, Bombus terrestris. The three traits analysed were the parasite's infection intensity, the strength of the general immune response (measured as the encapsulation of a novel antigen) and body size. The genetic architecture of these traits was examined in three natural, unmanipulated mapping populations of B. terrestris. Our results indicate that the intracolonial phenotypic variation of all three traits is based on a network of QTLs and epistatic interactions. While these networks are similar between mapping populations in complexity and number of QTLs, as well as in their epistatic interactions, the variability in the position of QTL and the interacting loci was high. Only one QTL for body size was plausibly found in at least two populations. QTLs for encapsulation and Crithidia infection intensity were located on the same linkage groups.