bluuebunny/crossref_metadata_2025 huggingface dataset:
Self-affine fluctuations of pions and protons and nonthermal phase transition in hadron–nucleus interactions
Authors: Ghosh D , Deb A , Pal S , Ghosh J
Published: January 2009

The paper reports a study revealing self-affine fluctuations in pion, proton, and compound multiplicity (of pions combined with protons) spectra obtained from the interactions of 350 GeV pions with AgBr nuclei. The study is performed in the transformed two-dimensional phase space of the emission and azimuthal angles using the factorial moment methodology and the concept of the Hurst exponent. Evidence of a nonthermal phase transition is obtained for self-affine fluctuations of pions along with an indication for such a regime to be seen in similar fluctuations of proton and compound multiplicity distributions. The study bridges the anisotropic nature of the multiparticle production process and an evidence of the nonthermal phase transition with similar earlier findings from hadron–hadron and nucleus–nucleus interactions and shows the same effects to be peculiar features of the multiplicity distributions of the different species of particles produced. All this brings important information about the underlying dynamics of the hadroproduction process.PACS Nos.: 25.80.Hp, 24.60.Ky, 13.85.–t
The appearance of the objects rolling at relativistic speeds
Authors: Sfarti A
Published: January 2009

In the late 1950s Terrell and Penrose produced a series of papers dealing with the appearance of the rapidly moving bodies while in rectilinear motion as photographed by a simple, pinhole camera. A few more articles on the same subject followed, for example, Penrose showed that a sphere is always seen having an exactly circular outline, at any velocity, at any distance and for any line of sight. In the present paper, we will deal with a more complex type of motion, the combination of translation and rotation that can be seen when observing the wheels of a vehicle passing by. Since Terrell and Penrose wrote their papers, great advances in the camera simulation via computer representation have been made. The field that deals with the simulation of realistic cameras via computers is called ray tracing. In the current paper, we will combine two different disciplines, relativistic physics and three-dimensional graphics to derive new results. Our paper is divided in two main parts, in the first half, we will derive the relativistic equations for rolling motion without slip and we will make some connections with the physical requirements of a relativistic ray-tracing algorithm. In the second half, we will review the foundations of classical ray-tracing algorithms and we will introduce the additional features for operation at relativistic speeds. We will demonstrate an interesting self-canceling effect of the relativistic Doppler shift on the colors wavelengths of the moving object.PACS No.: 03.30.+p
Control of cavity tones using a spanwise cylinder
Authors: Keirsbulck L , Hassan M El , Lippert M , Labraga L
Published: January 2009

A detailed experimental study of flow over a deep cavity was conducted towards understanding the attenuation of tones using a spanwise cylinder. Two “no-control” cavities were compared with a similar configuration using a cylinder on the leading edge of the cavities. Parametric changes of the spanwise cylinder such as the distance from the wall are studied. Maximum control across the range of studied velocities occurs for a particular position of the spanwise cylinder for the two configurations. Reductions in sound pressure levels (SPL) of up to 36 dB were obtained. Moreover, a shaped cylinder was also studied and shows that the attenuation of tones is not due to high-frequency pulsing as suggested in the literature, but to an increase of the cavity-shear-layer thickness due to the change in the mean axial velocity profiles.PACS Nos.: 47.27.Rc, 47.27.Sd
Modified photon-added coherent states: Generation and relatedentangled states
Authors: Liang M -L , Zhang J -N , Yuan B
Published: January 2009

We construct one new type of quantum state that we call the modified photon-added coherent state (MPACS) of the radiation field. These states are created by repeatedly applying the Hermitian operator (a + a+) to the coherent state m times. It turns out that these states are the superpositions of the coherent and the photon-added coherent states, and have highly nonclassical behavior depending on the excitation m and other parameters. The one-mode and two-mode modified entangled coherent states are also studied. MPACS can be generated through the atom-field interaction under the nonrotating wave approximation. PACS Nos.: 42.50.Dv, 03.65.Ca, 03.65.Ud
Theoretical spin-orbit structure of the alkali dimer cation K2+
Authors: Jraij A , Allouche A R , Magnier S , Aubert-Frecon M
Published: January 2009

A theoretical study of the electronic structure of [Formula: see text] including spin-orbit effects has been performed. Potential energy curves for the 58 molecular states in the representation Ωg,u are presented. Equilibrium distances, transition energies, depths for wells, and heights for humps predicted at short and large range of internuclear distances R are reported for all the bound states [Formula: see text] and Ωg,u dissociating to limits up to K++K(6p 2P3/2). Transition dipole moments have been calculated for all the allowed transitions among states [Formula: see text] dissociating to limits up to K+ +K(3d 2D). To the best of our knowledge, these are the first data reported for the Ωg,u states of [Formula: see text]. Extensive tables of energy values and transition dipole moments versus internuclear distances are available at the web address: http://www-lasim.univ-lyon1.fr/spip.php?rubrique99.PACS Nos.: 31.10.+z, 31.15.A–, 31.15.aj
(1+1)-dimensional m-cKdV, g-cKdV integrable systems, and (2+1)-dimensional m-cKdV hierarchy
Authors: Zhang Y , Tam H
Published: January 2009

A few isospectral problems are introduced by referring to that of the cKdV equation hierarchy, for which two types of integrable systems called the (1 + 1)-dimensional m-cKdV hierarchy and the g-cKdV hierarchy are generated, respectively, whose Hamiltonian structures are also discussed by employing a linear functional and the quadratic-form identity. The corresponding expanding integrable models of the (1 + 1)-dimensional m-cKdV hierarchy and g-cKdV hierarchy are obtained. The Hamiltonian structure of the latter one is given by the variational identity, proposed by Ma Wen-Xiu as well. Finally, we use a Lax pair from the self-dual Yang–Mills equations to deduce a higher dimensional m-cKdV hierarchy of evolution equations and its Hamiltonian structure. Furthermore, its expanding integrable model is produced by the use of a enlarged Lie algebra.PACS Nos.: 02.30, 03.40.K
Numerical solutions of magneto-hydrodynamic flow past a sphere at high Reynolds numbers
Authors: Ambethkar V
Published: January 2009

Numerical solutions of a steady, incompressible magneto-hydrodynamic flow past a sphere at high Reynolds numbers are presented by using finite differences in spherical polar coordinates with an applied magnetic field parallel to the main flow. Nonlinear coupled governing equations are solved numerically using finite-difference techniques. The results are presented up to Reynolds’ number R ≤ 10 000 and interaction parameter N = 25. Stability and convergence of the finite-difference technique has been discussed. Contours of stream lines and the vorticity are represented graphically up to high Reynolds number R ≤ 10 000 and N = 25. The values of the minimum stream function and vorticity at the primary vortex for different Reynolds numbers are tabulated and discussed.PACS Nos.: 47.11.Bc, 47.27.Jv, 47.63.mc, 52.65.Kj
Magnetic and magneto-optical properties of ultrathin films of iron epitaxied on iridium (001)
Authors: Boukelkoul M , Kharoubi M , Haroun A
Published: January 2009

We have theoretically studied the structural, magnetic, and magneto-optical behaviours of Fe ultra-thin films pseudomorphically epitaxied on semi-infinite Ir(001). The magnetic film crystallizes in the body-centered tetragonal (bct) structure with a tetragonality ratio 1.21. The new crystalline structure of iron in the magnetic film enhances the magnetic properties and a correlation between the interlayer spacing and the magnetic moment is found. The calculation of the magnetic properties shows a ferromagnetic interlayer coupling. The polar magneto-optical Kerr effect (P-MOKE) spectra are calculated over a photon energy range extended to 10~eV. The microscopic origin of the most interesting features is explained from interband transitions in various regions of the Brillouin zone.PACS Nos.: 78.20.Bh, 78.20.Ls
Seasonal variation of red blood cell survival in desert bighorn sheep (Ovis canadensis cremnobates)
Authors: Turner Jack C.
Published: January 2009

The life-span of red blood cells (RBCs) in captive and free-ranging desert bighorn sheep was measured with [32P]diisopropylfluorophosphate. The mean winter RBC life-span (156.6 days) was not significantly affected by season for captive animals maintained on a high nutritional plane and water, ad libitum. Free-ranging bighorn demonstrated a significant (P < 0.001) difference between mean winter (155.9 days) and summer (203.9 days) RBC survival. Dehydration of captive bighorn significantly increased RBC survival, closely approximating that found in summer free-ranging animals. Desert bighorn RBCs exhibited an aseasonal facultative response to the availability of water. RBC life-span was significantly (P < 0.05) increased from 153.5 to 197.7 days in animals experiencing extreme dehydration. The large spleen, relative to body weight, may accommodate extensive fluctuations in total RBC volume measured during dehydration and rehydration, preventing premature RBC degradation and an increased water requirement.
Ultrastructural features of the gut of Sitophilus granarius (L.) (Coleoptera: Curculionidae) with notes on distribution of proteinases and amylases in crop and midgut
Authors: Baker J. E. , Woo S. M. , Byrd R. V.
Published: January 2009

In addition to typical columnar cells, dark-staining cells characterized by deep invaginations of basal plasma membranes were found throughout the midgut of adult Sitophilus granarius (L.). These invaginations formed intracellular channels that extended to the perinuclear region and indicated an involvement of these cells in secretion and (or) absorption. Cells with large vacuolelike structures that occasionally filled the entire supranuclear region were found in the anterior midgut, while multicellular crypts and cells that formed apical extrusions into the lumen were common in the posterior midgut. Fine structure of gastric caeca indicated functional differences between those located in anterior and posterior midgut regions. Numerous dark-staining granules were found in apical regions of cells of the anterior caeca, whereas elongated mitochondria were found in microvilli that made up the brush border of posterior caecal cells. Thus, although the midgut is not obviously differentiated into zones, there are different cell types in different regions of the gut involved in digestive and nutrient absorption processes. Evidence indicated that amylase in S. granarius is secreted by salivary glands whereas trypsin and aminopeptidase are secreted by midgut. A slow, continuous secretion of amylase occurs whereas proteinases are secreted in response to ingested food.
Sites de nidification et dynamique des populations du Cormoran à aigrettes au Québec
Authors: DesGranges J.-L. , Chapdelaine G. , Dupuis P.
Published: January 2009

Some 12 000 pairs of Double-crested Cormorants (Phalacrocorax auritus) nested in Québec in 1979. They were divided among 43 colonies and were all located in a marine environment. Three-quarters of the colonies and four-fifths of the nests are currently found on islands but they are also seen on the face of cliffs on the mainland. The nests are built both in trees and on the ground. Generally, the ecological location of the Cormorant colonies and nests are closely related to the regional availability of different kinds of sites. There has been an increase in the total number of nests in three-quarters of the colonies in the province over the last decade. Increased protection of colonial waterbirds, particularly in breeding colonies, and changes in social attitudes have almost completely eliminated the harassment to which the Double-crested Cormorant has long been subjected in Québec. The suppression of this major obstacle to their growth rate probably explains why the Québec populations of the Double-crested Cormorant are currently on the increase.
Nest site selection and survivorship of Dolichovespula arenaria and Dolichovespula maculata (Hymenoptera: Vespidae)
Authors: Pallett Megan J.
Published: January 2009

Recurrence of Dolichovespula nests in previous nest site areas was high. Searches for nests in successive years will be more efficient if confined to these areas. Dolichovespula arenaria queens were as likely to build on or near old D. maculata sites as on old D. arenaria sites. Dolichovespula maculata queens favoured sites not used previously by D. arenaria. Dolichovespula arenaria may be less selective than D. maculata in choosing nest sites. Dolichovespula arenaria can successfully usurp colonies of D. maculata. Weather-related bird predation is a major contributor to the mortality of young Dolichovespula colonies. Cool, damp June weather increases the incidence of successful bird predation. Dolichovespula arenaria will kill and remove D. arctica from its nest, and at least two D. arctica queens will cohabit a colony of D. arenaria, suggesting there is less intraspecific aggression in D. arctica than previously reported.
Ecological characterization of two sibling species, IIIL-1 and IS-7, in the Simulium vittatum complex (Diptera: Simuliidae)
Authors: Adler Peter H. , Kim Ke Chung
Published: January 2009

Larval polytene chromosomes provided the identification tool that enabled ecological characterization of two black fly sibling species, IIIL-1 and IS-7, in the Simulium vittatum complex. A 4-year study in the eastern United States demonstrated important differences between the two siblings, based primarily on differential occupancy of the stream continuum. Immatures of the IIIL-1 sibling predominated below nonspring-fed reservoirs, downstream of sewage effluent outflows, and in warm downstream areas. Immatures of the IS-7 sibling occurred, with IIIL-1, in cool well-oxygenated flows generally associated with groundwater discharge. These sibling–habitat relations produced sibling gradients along the stream continuum. Over their geographic ranges, the IIIL-1 sibling became increasingly abundant from north to south, relative to IS-7. At mixed-sibling sites, populations were asynchronous; IS-7 generally predominated in early spring and late fall. The major determinants of sibling distributions were those factors affecting respiration: temperature, oxygen, and current. Species such as the black fly Simulium decorum and the midge Chironomus riparius signalled essentially pure populations of IIIL-1. Preimaginal densities of Glossosoma spp. (Trichoptera) also indicated sibling proportions. IIIL-1 and IS-7 shared all pathogens. At mixed-sibling sites, proportionally more larvae of IIIL-1 occurred on rocks than on grasses. Regardless of sibling, larvae on rocks were darker than those on grasses, which suggested differences in the proportion of ingested materials.
Development of Raphidascaris acus (Nematoda, Anisakidae) in paratenic, intermediate, and definitive hosts
Authors: Smith John D.
Published: January 2009

Larval development and morphology of Raphidascaris acus were studied in experimentally infected invertebrates and fish. Previous studies disagreed on the roles of these hosts. Raphidascaris acus develops to the second stage in the egg. Eggs are then infective to both invertebrates and fish. Larvae did not develop in experimentally infected amphipods or chironomid larvae. In experimentally infected darters (Etheostoma spp.) and yellow perch (Perca flavescens), larvae migrated to the liver and developed to the fourth stage, not the third as reported by others. The larvae moulted at 1.3 and 2.2–2.5 mm in these fish and grew to 5–6 mm. Therefore, invertebrates act as paratenic hosts and make the larvae available to fish which act as intermediate hosts. Definitive hosts (northern pike, Esox lucius; rainbow trout, Salmo gairdneri; brook trout, Salvelinus fontinalis) were infected experimentally using fourth-stage larvae. The parasite attained the adult stage in the gut of these fish, moulting at about 6 mm and maturing in about 1 month at 12–14 °C. The stages of R. acus are readily distinguished by reproductive organs and cephalic structures. A boring tooth is present in the second and third stages, nonpedunculate lips are present in the fourth stage, and pedunculate lips are present in the adult. Fourth-stage larvae have a ventral interlabium.
The sounds of the bowhead whale, Balaena mysticetus, during the spring migrations of 1979 and 1980
Authors: Clark Christopher W. , Johnson James H.
Published: January 2009

Bowhead whales, Balaena mysticetus, were recorded during their spring migration past Point Barrow, Alaska, in 1979 and 1980 using a pair of hydrophones linked to an underwater sound direction finding device. A great variety of sounds were recorded, including types that have been reported previously for bowheads during their spring migration, fall migration, and summer feeding. Most of the sounds were below 300 Hz with simple frequency-modulated structures. A variety of pulsive sounds were also recorded; these contained complex energy up to 3500 Hz. Sound levels of approximately 156 dB (re 1 μPa) were recorded for one whale 100–150 m from the hydrophones. We did not observe any particular behaviors which correlated with any of these sounds.
RECOVERING THE BASIC STRUCTURE OF HUMAN ACTIVITIES FROM NOISY VIDEO-BASED SYMBOL STRINGS
Authors: KITANI KRIS M. , SATO YOICHI , SUGIMOTO AKIHIRO
Published: January 2009

In recent years stochastic context-free grammars have been shown to be effective in modeling human activities because of the hierarchical structures they represent. However, most of the research in this area has yet to address the issue of learning the activity grammars from a noisy input source, namely, video. In this paper, we present a framework for identifying noise and recovering the basic activity grammar from a noisy symbol string produced by video. We identify the noise symbols by finding the set of non-noise symbols that optimally compresses the training data, where the optimality of compression is measured using an MDL criterion. We show the robustness of our system to noise and its effectiveness in learning the basic structure of human activity, through experiments with artificial data and a real video sequence from a local convenience store.
A FAST APPROXIMATION OF THE EARTH-MOVERS DISTANCE BETWEEN MULTIDIMENSIONAL HISTOGRAMS
Authors: SERRATOSA FRANCESC , SANROMÀ GERARD
Published: January 2009

We present an efficient algorithm for computing a sub-optimal Earth Movers' Distance (EMD) between multidimensional histograms called EMD- g f, which is not limited to any type of measurement. Some algorithms that find a cross-bin distance between histograms have been proposed in the literature. Nevertheless, most of this research has been applied on 1D-histograms or on nD-histograms but with limited types of measurements. The EMD is a cross-bin distance between nD-histograms with any ground distance. Experimental validation shows that it obtains good retrieval results although the main drawback of this method is its cubic computational cost, O(z3), z being the total number of bins. The worst-case complexity of EMD- g f is O(z2), although the obtained average computational cost in the experiments is near O(m2), where m represents the number of bins per dimension, which is clearly lower than the computational cost of the EMD algorithm. Moreover, the experiments using real data show similar retrieval results.
HIGH-STIFFNESS AND HIGH-SENSITIVITY 3-AXIS FORCE SENSOR USING STRAIN-DEFORMATION EXPANSION MECHANISM
Authors: YU YONG , CHAEN TAKASHI , TSUJIO SHOWZOW
Published: January 2009

For dexterously performing object grasping and manipulation with multifingered hand of robot, sensing the fingertip forces with high-sensitivity and high-stiffness is desired. In general, based on previous sensing structures, we have to reduce a sensor's stiffness for obtaining a higher sensitivity of the sensor. It is hard to realize the force sensing with both of high-sensitivity and high-stiffness by previous sensing structures. This paper proposes a novel mechanism called Strain-Deformation Expansion Mechanism for 3-axis force sensing. By the force sensing mechanism, the small strain-deformation used for force sensing can be expanded while the sensor stiffness will not be reduced but will be heightened. In this paper, the force sensing principle is addressed by analyzing the deformation of the sensing mechanism and the forces acting on the sensor theoretically. Then, the sensitivity of the sensing mechanism and its expansion rate of sensitivity are defined, and a design method for realizing the sensing mechanism with high sensitivity is discussed. Lastly, some experiments are performed to show the basic characteristics and the effectiveness of the sensing mechanism.
Dual suppression of adipogenesis by cigarette smoke through activation of the aryl hydrocarbon receptor and induction of endoplasmic reticulum stress
Authors: Shimada Tsuyoshi , Hiramatsu Nobuhiko , Hayakawa Kunihiro , Takahashi Shuhei , Kasai Ayumi , Tagawa Yasuhiro , Mukai Mai , Yao Jian , Fujii-Kuriyama Yoshiaki , Kitamura Masanori
Published: January 2009

Cigarette smoking decreases body weight, whereas molecular mechanisms underlying this phenomenon have not been elucidated. In this report, we investigated regulation of adipogenesis by cigarette smoke and involvement of aryl hydrocarbon receptor (AhR) and endoplasmic reticulum (ER) stress. We found that cigarette smoke extract (CSE) inhibited differentiation of preadipocytes into adipocytes dose dependently. It was associated with a decrease in lipid accumulation, blunted expression of adipocyte markers (adiponectin, PPAR-γ, and C/EBPα), and sustained expression of a preadipocyte marker MCP-1. CSE markedly induced activation of AhR, and AhR agonists (2,3,7,8-tetrachlorodibenzo- p-dioxin, benzo[ a]pyrene and 3-methylcholanthrene) reproduced the inhibitory effect of CSE on adipocyte differentiation. Furthermore, knockout of the AhR gene or blockade of AhR by a dominant-negative mutant attenuated the suppressive effects of CSE on adipocyte differentiation. We also found that CSE induced ER stress in preadipocytes, and ER stress inducers (thapsigargin, tunicamycin, and A23187) reproduced the suppressive effect of CSE on the differentiation of preadipocytes. Interestingly, AhR agonists did not cause ER stress, and ER stress inducers did not activate AhR. These results suggested that cigarette smoke has the potential to inhibit adipocyte differentiation via dual, independent mechanisms, i.e., through activation of the AhR pathway and induction of the unfolded protein response.
In obese rat muscle transport of palmitate is increased and is channeled to triacylglycerol storage despite an increase in mitochondrial palmitate oxidation
Authors: Holloway Graham P. , Benton Carley R. , Mullen Kerry L. , Yoshida Yuko , Snook Laelie A. , Han Xiao-Xia , Glatz Jan F. C. , Luiken Joost J. F. P. , Lally James , Dyck David J. , Bonen Arend
Published: January 2009

Intramuscular triacylglycerol (IMTG) accumulation in obesity has been attributed to increased fatty acid transport and/or to alterations in mitochondrial fatty acid oxidation. Alternatively, an imbalance in these two processes may channel fatty acids into storage. Therefore, in red and white muscles of lean and obese Zucker rats, we examined whether the increase in IMTG accumulation was attributable to an increased rate of fatty acid transport rather than alterations in subsarcolemmal (SS) or intermyofibrillar (IMF) mitochondrial fatty acid oxidation. In obese animals selected parameters were upregulated, including palmitate transport (red: +100%; white: +51%), plasmalemmal FAT/CD36 (red: +116%; white: +115%; not plasmalemmal FABPpm, FATP1, or FATP4), IMTG concentrations (red: ∼2-fold; white: ∼4-fold), and mitochondrial content (red +30%). Selected mitochondrial parameters were also greater in obese animals, namely, palmitate oxidation (SS red: +91%; SS white: +26%; not IMF mitochondria), FAT/CD36 (SS: +65%; IMF: +65%), citrate synthase (SS: +19%), and β-hydroxyacyl-CoA dehydrogenase activities (SS: +20%); carnitine palmitoyltransferase-I activity did not differ. A comparison of lean and obese rat muscles revealed that the rate of change in IMTG concentration was eightfold greater than that of fatty acid oxidation (SS mitochondria), when both parameters were expressed relative to fatty transport. Thus fatty acid transport, esterification, and oxidation (SS mitochondria) are upregulated in muscles of obese Zucker rats, with these effects being most pronounced in red muscle. The additional fatty acid taken up is channeled primarily to esterification, suggesting that upregulation in fatty acid transport as opposed to altered fatty acid oxidation is the major determinant of intramuscular lipid accumulation.
Cytokine-induced F-actin reorganization in endothelial cells involves RhoA activation
Authors: Campos Silvia B. , Ashworth Sharon L. , Wean Sarah , Hosford Melanie , Sandoval Ruben M. , Hallett Mark A. , Atkinson Simon J. , Molitoris Bruce A.
Published: January 2009

Acute ischemic kidney injury results in marked increases in local and systemic cytokine levels. IL-1α, IL-6, and TNF-α orchestrate various inflammatory reactions influencing endothelial permeability by altering cell-to-cell and cell-to-extracellular matrix attachments. To explore the role of actin and the regulatory proteins RhoA and cofilin in this process, microvascular endothelial cells (MS1) were exposed to individual cytokines or a cytokine cocktail. Within minutes, a marked, time-dependent redistribution of the actin cytoskeleton occurred with the formation of long, dense F-actin basal stress fibers. The concentration of F-actin, normalized to nuclear staining, significantly increased compared with untreated cells (up 20%, P ≤ 0.05). Western blot analysis of MS1 lysates incubated with the cytokine cocktail for 4 h showed an increase in phosphorylated/inactive cofilin (up 25 ± 15%, P ≤ 0.05) and RhoA activation (up to 227 ± 26% increase, P ≤ 0.05) compared with untreated cells. Decreasing RhoA levels using small interfering RNA blocked the effect of cytokines on stress fiber organization. Treatment with Y-27632, an inhibitor of the RhoA effector p160-ROCK, decreased levels of phosphorylated cofilin and reduced stress fiber fluorescence by 22%. In cells treated with Y-27632 followed by treatment with the cytokine cocktail, stress fiber levels were similar to control cells and cofilin phosphorylation was 55% of control levels. Taken together, these studies demonstrate cytokine stimulation of RhoA, which in turn leads to cofilin phosphorylation and formation of numerous basal actin stress fibers. These results suggest cytokines signal through the Rho-ROCK pathway, but also through another pathway to affect actin dynamics.
Existence Results for Generalized Vector Equilibrium Problems with Multivalued Mappings via KKM Theory
Authors: Farajzadeh A. P. , Amini-Harandi A. , O′Regan D.
Published: January 2009

We first define upper sign continuity for a set‐valued mapping
and then we consider two types of generalized vector equilibrium problems in topological
vector spaces and provide sufficient conditions under which the solution sets are nonempty
and compact. Finally, we give an application of our main results. The paper generalizes
and improves results obtained by Fang and Huang in (2005).
Faciogenital Dysplasia Protein Fgd1 Regulates Invadopodia Biogenesis and Extracellular Matrix Degradation and Is Up-regulated in Prostate and Breast Cancer
Authors: Ayala Inmaculada , Giacchetti Giada , Caldieri Giusi , Attanasio Francesca , Mariggiò Stefania , Tetè Stefano , Polishchuk Roman , Castronovo Vincent , Buccione Roberto
Published: January 2009

Invadopodia are proteolytically active membrane protrusions that extend from the ventral surface of invasive tumoral cells grown on an extracellular matrix (ECM). The core machinery controlling invadopodia biogenesis is regulated by the Rho GTPase Cdc42. To understand the upstream events regulating invadopodia biogenesis, we investigated the role of Fgd1, a Cdc42-specific guanine nucleotide exchange factor. Loss of Fgd1 causes the rare inherited human developmental disease faciogenital dysplasia. Here, we show that Fgd1 is required for invadopodia biogenesis and ECM degradation in an invasive cell model and functions by modulation of Cdc42 activation. We also find that Fgd1 is expressed in human prostate and breast cancer as opposed to normal tissue and that expression levels matched tumor aggressiveness. Our findings suggest a central role for Fgd1 in the focal degradation of the ECM in vitro and, for the first time, show a connection between Fgd1 and cancer progression, proposing that it might function during tumorigenesis. [Cancer Res 2009;69(3):747–52]
Transcriptional Repression of Epithelial Cell Adhesion Molecule Contributes to p53 Control of Breast Cancer Invasion
Authors: Sankpal Narendra V. , Willman Michael W. , Fleming Timothy P. , Mayfield John D. , Gillanders William E.
Published: January 2009

p53 is a tumor suppressor gene with well-characterized roles in cell cycle regulation, apoptosis, and maintenance of genome stability. Recent evidence suggests that p53 may also contribute to the regulation of migration and invasion. Epithelial cell adhesion molecule (EpCAM) is a transmembrane glycoprotein that is overexpressed in the majority of human epithelial carcinomas, including breast and colorectal carcinomas. We show by chromatin immunoprecipitation assays that p53 interacts with a candidate p53 binding site within the EpCAM gene. p53-mediated transcriptional repression of EpCAM was confirmed in gain-of-function and loss-of-function experimental systems. Induction of wild-type p53 was associated with a significant dose-dependent decrease in EpCAM expression; conversely, specific ablation of p53 was associated with a significant increase in EpCAM expression. At the functional level, specific ablation of p53 expression is associated with increased breast cancer invasion, and this effect is abrogated by concomitant specific ablation of EpCAM expression. Taken together, these biochemical and functional data are the first demonstration that (a) wild-type p53 protein binds to a response element within the EpCAM gene and negatively regulates EpCAM expression, and (b) transcriptional repression of EpCAM contributes to p53 control of breast cancer invasion. [Cancer Res 2009;69(3):753–7]
Intakes of Red Meat, Processed Meat, and Meat Mutagens Increase Lung Cancer Risk
Authors: Lam Tram Kim , Cross Amanda J. , Consonni Dario , Randi Giorgia , Bagnardi Vincenzo , Bertazzi Pier Alberto , Caporaso Neil E. , Sinha Rashmi , Subar Amy F. , Landi Maria Teresa
Published: January 2009

Red and processed meat intake may increase lung cancer risk. However, the epidemiologic evidence is inconsistent and few studies have evaluated the role of meat mutagens formed during high cooking temperatures. We investigated the association of red meat, processed meat, and meat mutagen intake with lung cancer risk in Environment And Genetics in Lung cancer Etiology, a population-based case-control study. Primary lung cancer cases (n = 2,101) were recruited from 13 hospitals within the Lombardy region of Italy examining ∼80% of the cases from the area. Noncancer population controls (n = 2,120), matched to cases on gender, residence, and age, were randomly selected from the same catchment area. Diet was assessed in 1,903 cases and 2,073 controls and used in conjunction with a meat mutagen database to estimate intake of heterocyclic amines (HCA) and benzo(a)pyrene (BaP). Multivariable odds ratios (OR) and 95% confidence intervals (95% CI) for sex-specific tertiles of intake were calculated using unconditional logistic regression. Red and processed meat were positively associated with lung cancer risk (highest-versus-lowest tertile: OR, 1.8; 95% CI, 1.5–2.2; P trend < 0.001 and OR, 1.7; 95% CI, 1.4–2.1; P trend < 0.001, respectively); the risks were strongest among never smokers (OR, 2.4; 95% CI, 1.4–4.0; P trend = 0.001 and OR, 2.5; 95% CI, 1.5–4.2; P trend = 0.001, respectively). HCAs and BaP were significantly associated with increased risk of lung cancer. When separated by histology, significant positive associations for both meat groups were restricted to adenocarcinoma and squamous cell carcinoma but not small cell carcinoma of the lung. In summary, red meat, processed meat, and meat mutagens were independently associated with increased risk of lung cancer. [Cancer Res 2009;69(3):932–9]
Ubiquitous yet Distinct Expression of Podocalyxin on Vascular Surfaces in Normal and Tumor Tissues in the Rat
Authors: Testa Jacqueline E. , Chrastina Adrian , Li Yan , Oh Phil , Schnitzer Jan E.
Published: January 2009

Background/Aims: The vasculature has become an important target in the development of therapies for increasing numbers of human diseases, yet there are few reliable markers available to identify the endothelium in rodent models. We have characterized the expression, subcellular localization and accessibility of the rat pan-endothelial marker podocalyxin (podxl) using a newly developed monoclonal antibody (mAb), G278. Methods: podxl expression and accessibility to binding by G278 were determined in the rat by a variety of experimental approaches. Results: mAb G278 reliably immunostained blood vessels of all types and of every size in fresh-frozen, fixed-frozen and paraffin-embedded sections of all tissues, but did not stain lymphatic vessels. Western blotting, in vivo imaging and biodistribution analyses demonstrated that the highest levels of endothelial podxl were found in the lung and heart. We also determined that podxl is not enriched in caveolae and that its expression can be modulated in the tumor microenvironment. Conclusion: Our study shows that podxl is a better identifier of rat endothelia than are some of the more commonly used markers and that mAb G278 is a robust antibody for use not only in identifying rat blood vessels but also as a tool to elucidate podxl function.
Prostaglandin E Positively Modulates Endothelial Progenitor Cell Homeostasis: An Advanced Treatment Modality for Autologous Cell Therapy
Authors: Herrler Tanja , Leicht Simon F. , Huber Stephan , Hermann Patrick C. , Schwarz Theresa M. , Kopp Reinhard , Heeschen Christopher
Published: January 2009

Aims: The mobilization of endothelial progenitor cells (EPC) and their functioning in postnatal neovascularization are tightly regulated. To identify new modulators of EPC homeostasis, we screened biologically active prostaglandin E compounds for their effects on EPC production, trafficking and function. Methods and Results: We found that EPC are a rich source for prostaglandin E2 (PGE2), stimulating their number and function in an auto- and paracrine manner. In vivo blockade of PGE2 production by selective cyclooxygenase-2 inhibition virtually abrogated ischemia-induced EPC mobilization demonstrating its crucial role in EPC homeostasis following tissue ischemia. Conversely, ex vivo treatment of isolated EPC with the clinically approved PGE1 analogue alprostadil enhanced EPC number and function. These effects were mediated by increased expression of the chemokine receptor CXCR4 and were dependent on nitric oxide synthase activity. Most importantly, ex vivo PGE1 pretreatment of isolated EPC significantly enhanced their neovascularization capacity in a murine model of hind limb ischemia as assessed by laser Doppler analysis, exercise stress test and immunohistochemistry. Conclusions: The conserved role for PGE in the regulation of EPC homeostasis suggests that ex vivo modulation of the prostaglandin pathway in isolated progenitor cells may represent a novel and safe strategy to facilitate cell-based therapies.
Effect of Organ Culture on Noradrenaline- Evoked Contraction, Calcium Signalling and TRPC Expression in Rat Mesenteric Artery
Authors: Tai Khalid , Vandenberg Greet , Hamaide Marie-Christine , Wibo Maurice , Morel Nicole
Published: January 2009

The aim of this study was to explore the changes evoked by organ culture in the signalling pathways activated by noradrenaline in rat resistance mesenteric artery. Contractile responses and calcium signalling were significantly more sensitive to noradrenaline in arteries cultured for 48–72 h in the absence of growth factors compared to fresh arteries. Both calcium release activated by noradrenaline in calcium-free solution and calcium entry measured after the addition of external calcium were higher in cultured arteries than in fresh tissue. Blockers of non-selective cation channels (SKF-96365, flufenamic acid, Gd3+) more potently inhibited noradrenaline contraction in cultured arteries than in fresh ones. The src kinase inhibitors genistein or PP2 normalised the increased contraction and the increased calcium release evoked by noradrenaline in cultured arteries. In cultured arteries, trpc1 (transient receptor potential canonical 1) mRNA expression was decreased by 47 ± 8% (n = 5, p < 0.05), while trpc6 mRNA expression was increased by 92 ± 24% (n = 5, p < 0.05) in comparison with non-cultured arteries. Immunofluorescence analysis of protein expression confirmed the up-regulation of TRPC6 protein after culture. These results indicate that mesenteric artery culture results in src kinase-dependent increase in the responses to noradrenaline and in a change in cation channel activity, which could contribute to the increased contraction.
Rhein Inhibits TNF-α-Induced Human Aortic Smooth Muscle Cell Proliferation via Mitochondrial-Dependent Apoptosis
Authors: Heo Sook-Kyoung , Yun Hyun-Jeong , Park Won-Hwan , Park Sun-Dong
Published: January 2009

Background: Vascular smooth-muscle cell proliferation plays an important role in atherosclerosis and restenosis. Rhein is an active component extracted from rhubarb. In this study, rhein was found to exert potent inhibitory effects against tumor necrosis factor (TNF)-α-induced human aortic smooth-muscle cells (HASMCs) proliferation. Method: These effects were associated with induced apoptosis, including the induction of Annexin V-positive cells, the cleavage of poly(ADP-ribose)polymerase (PARP), and caspases 3, 8 and 9. Results: Inhibitors of caspases 3, 8 and 9 were efficiently blocked by rhein-induced apoptosis in TNF-α-treated HASMCs. In addition, treatment with rhein resulted in the release of cytochrome c into the cytosol, a loss of mitochondrial membrane potential (ΔΨm), a decrease in Bcl-2 and Bcl-xL and an increase in Bax and Bak expression. However, rhein-mediated apoptosis was blocked by a mitochondrial membrane depolarization inhibitor. These findings indicate that rhein-induced apoptosis occurred via a mitochondrial pathway. Furthermore, the inhibition of mitochondrial membrane depolarization was efficiently blocked by rhein-induced caspase-9 activity, which indicates that the rhein-induced caspase activation signal was downstream of the mitochondrial pathway. Taken together, the results of this study show that rhein inhibits TNF-α-induced HASMC proliferation via mitochondria-dependent apoptosis and that rhein has the potential to act as an anti-atherosclerosis agent.
Evaluation of Small Bowel Injury in Patients with Rheumatoid Arthritis by Capsule Endoscopy: Effects of Anti-Rheumatoid Arthritis Drugs
Authors: Sugimori Satoshi , Watanabe Toshio , Tabuchi Masahiko , Kameda Natsuhiko , Machida Hirohisa , Okazaki Hirotoshi , Tanigawa Tetsuya , Yamagami Hirokazu , Shiba Masatsugu , Watanabe Kenji , Tominaga Kazunari , Fujiwara Yasuhiro , Oshitani Nobuhide , Koike Tatsuya , Higuchi Kazuhide , Arakawa Tetsuo
Published: January 2009

Background and Aim: The medical treatment of rheumatoid arthritis (RA) includes nonsteroidal anti-inflammatory drugs (NSAIDs), low-dose corticosteroids, and disease-modifying antirheumatic drugs (DMARDs). We evaluated the incidence of small bowel injury in RA patients who were taking anti-RA drugs with or without concomitant NSAIDs by capsule endoscopy. Methods: A total of 28 RA patients who took low-dose corticosteroids and/or DMARDs for more than 1 year were enrolled. Results: The incidence of red spots did not differ between the 2 groups: 14 of 16 patients (87.5%) in the NSAID group and 11 of 12 patients (91.7%) in the non-NSAID group. In contrast, the incidence of mucosal breaks was significantly higher in the NSAID group than in the non-NSAID group: mucosal breaks were detected in 13 of 16 patients (81.3%) and 4 of 12 patients (33.3%) in the NSAID and non-NSAID groups, respectively. In the NSAID group, mucosal breaks developed in users of preferential cyclooxygenase-2 inhibitors at a frequency similar to that in users of traditional NSAIDs. Conclusion: Patients taking anti-RA drugs may have an increased frequency of small bowel injury regardless of NSAID use, and NSAID use may be associated with an increased incidence of severe small bowel injury.
Nursing for Renal Replacement Therapies in the Intensive Care Unit: Historical, Educational, and Protocol Review
Authors: Baldwin Ian , Fealy Nigel
Published: January 2009

Nurses have made a significant contribution to the development and application of dialysis in the 1950s and continuous renal replacement therapies (CRRT) in the Intensive Care Unit (ICU) setting from the 1980s. Any treatment requires patient and machine-circuit preparation, connection of the extracorporeal circuit (EC) to the patient vascular access catheter and regular tasks to maintain a treatment in progress. During treatment, nurses prepare fluids, adjust fluid settings to provide fluid balance, prepare electrolyte additives, monitor acid base and electrolyte levels, monitor patient and machine ‘vital signs’, and then when necessary diagnose circuit clotting and perform a disconnection of the EC from the patient. All of these aspects of CRRT nursing are essential to a suitable nursing policy or protocol. This paper provides a clinical review for this every day sequence when using CRRT in the ICU setting.
Grape Seed Proanthocyanidins Ameliorate Diabetic Nephropathy via Modulation of Levels of AGE, RAGE and CTGF
Authors: Li Xianhua , Xiao Yunling , Gao Haiqing , Li Baoying , Xu Ling , Cheng Mei , Jiang Bei , Ma Yabing
Published: January 2009

Background: Diabetic nephropathy (DN) is the most common cause of end-stage renal failure. Grape seed proanthocyanidin extracts (GSPE) are powerful antioxidants. However, the role of GSPE on advanced glycation end products (AGEs), receptor for advanced glycation end products (RAGE) and expression of connective tissue growth factor (CTGF) in DN has not been elucidated. Using streptozotocin-induced diabetic rats, we evaluated the effects of GSPE in DN. Methods: Wistar rats were induced into diabetes using streptozotocin injections and diabetic rats were treated with GSPE (dosage: 500 mg·kg–1·day–1) for 24 weeks. The renal pathological changes were examined with PAS staining and electron microscope. The mRNA and protein expression of RAGE and CTGF in kidney were detected by RT-PCR, Western blot and immunohistochemical staining. Results: Treated animals showed reduction in serum AGEs (p < 0.01), proteinuria (p < 0.01) and systolic blood pressure (p < 0.01). GSPE reduced the expression of RAGE (p < 0.01) and CTGF (p < 0.01) in the kidney, which were contributing to reversal of extracellular matrix accumulation in DN. Conclusion: Our results suggest that GSPE hold substantial promise for the treatment of DN. GSPE can decrease proteinuria, attenuating the progression of nephropathy in diabetic rats. Renoprotective effects of GSPE are correlated with suppression on AGEs/RAGE axis, downregulating expression of CTGF.
Pharmacological Modulation of Dopaminergic Brain Activity and Its Reflection in Spectral Frequencies of the Rat Electropharmacogram
Authors: Dimpfel Wilfried
Published: January 2009

Background: Particular frequencies of electropharmacograms have been attributed to cholinergic, noradrenergic or dopaminergic mediated neurotransmission. This investigation deals with changes induced by L-DOPA or dopamine D2 receptor agonists. Method: Adult rats (day-night converted) were instrumented with four bipolar concentric semi-micro-electrodes into the frontal cortex, hippocampus, striatum and reticular formation. Field potentials were recorded during a pre-drug reference period followed by 4 h of recording thereafter. Data were transmitted wirelessly for spectral frequency analysis. Results: At low doses of L-DOPA (1–5 mg kg–1) and of the D2 agonists talipexole and quinpirole (0.1 mg kg–1), a delayed increase of delta and theta power was observed. Higher doses led to immediate stable decreases of alpha1, alpha2 and beta1 power as reported for dopamine D1 receptor agonists. Administration of the D2 blocker sulpiride (10–20 mg kg–1) resulted in increases of alpha2 power. Conclusion: A common denominator for changes of dopaminergic transmission could be seen in immediate changes of spectral alpha2 power. Delayed increases of delta and theta activity after low dosages of the medication are considered to originate from heterosynaptic, presynaptic D2 receptors sitting on cholinergic neurons. This pattern could explain daytime tiredness or sudden sleep attacks in Parkinson patients.
Genetic Analysis of Alzheimer’s Disease in the Uppsala Longitudinal Study of Adult Men
Authors: Giedraitis Vilmantas , Kilander Lena , Degerman-Gunnarsson Malin , Sundelöf Johan , Axelsson Tomas , Syvänen Ann-Christine , Lannfelt Lars , Glaser Anna
Published: January 2009

Background/Aims: Genetic factors influencing common complex conditions have proven difficult to identify, and data from numerous investigations have provided incomplete conclusions as to the identity of these genes. Here we aimed to identify susceptibility genes for late-onset Alzheimer’s disease (AD). Methods: The case-control analysis included samples from 86 AD patients and 404 cognitively healthy controls selected from the Uppsala Longitudinal Study of Adult Men (ULSAM). In the incidence analysis, all 1,088 genotyped ULSAM participants were included. DNA samples from ULSAM participants were analyzed for 2,578 single nucleotide polymorphisms (SNP) within 368 genes. The selection of genes tested for association to AD within this cohort was based on genes previously implicated in conditions with relevance to ULSAM, such as dementia, cardiovascular disease, diabetes and metabolic syndrome, osteoporosis, and cancer. Results/Conclusion: Association analysis revealed 82 genes containing at least 1 significant SNP at p < 0.05 with association to AD. Only 20 genes remained significant after a permutation test to correct for multiple comparisons within individual genes. Using publicly available data from 2 genome-wide association (GWA) studies and linkage disequilibrium data from HapMap, we attempted to replicate the AD association identified in ULSAM. In addition to apolipoprotein E, we were able to replicate 5 other genes in both GWA studies at p < 0.05.