bluuebunny/crossref_metadata_2025 huggingface dataset:
Single-host pathogen effects on mortality and behavioral responses to predators in salamanders (Urodela: Ambystomatidae)
Authors: Parris Matthew J , Davis Alison , Collins James P
Published: January 2005

Pathogens can alter host behavior and affect the outcome of predator-prey interactions. Acute phase responses of hosts (e.g., a change in activity level or behavioral fever) often signal an infection, but the ecological consequences of host behavioral changes largely are unexplored, particularly for directly transmitted (i.e., single-host) pathogens. We performed three experiments to test the hypothesis that a pathogen, Ambystoma tigrinum virus (ATV), alters host behavior of Sonoran tiger salamanders (Ambystoma tigrinum stebbinsi Lowe, 1954) and enhances predation. In the first experiment, salamander larvae exposed to ATV experienced 48% lower mortality from dragonfly Anax junius (Drury, 1773) larvae than those in controls. Second, uninfected and infected larvae exposed to the nonlethal (caged) presence of predators did not significantly differ in their distance from the predator. Infected salamanders significantly increased their activity level relative to those in controls in predator-free conditions. Finally, ATV-infected larvae preferred significantly warmer temperatures than uninfected larvae, but larvae reared at the thermal maximum for the virus all died. High host activity level yet retention of effective antipredator responses likely benefits ATV because this single-host pathogen relies on host survival for transmission. Preference for warmer temperatures may be associated with the host response to pathogens and may help fight infection.
NONLINEAR DYNAMICS ANALYSIS OF TRAFFIC TIME SERIES
Authors: LI KEPING , GAO ZIYOU
Published: January 2005

Traffic flow shows various complex behaviors. Numerous empirical data and numerical simulation results demonstrate the existence of distinct dynamics states. In order to obtain insight into the nature of the dynamics, we apply the nonlinear time series analysis approach to study the characteristic behavior of traffic flow at low and intermediate density values. A procedure called "embedding scheme" has been used to reconstruct the representation of the time series which is obtained from the deterministic NaSch traffic model. In the reconstructed phase space, we investigate the regular attractor and the chaotic attractor of traffic time series. Our results indicate that nonlinear technique can be successfully used for understanding of dynamics feature of traffic flow.
IMAGE WATERMARKING RESISTANT TO COMBINED GEOMETRIC AND REMOVAL ATTACKS
Authors: LEE CHOONG-HOON , LEE HEUNG-KYU , SUH YOUNGHO
Published: January 2005

In this paper, we propose an improved autocorrelation function (ACF)-based watermarking that is robust against combined geometric and removal attacks. ACF-based watermarking is known to be effective against geometric attacks. In this watermarking scheme, both the embedded watermark and autocorrelation peaks of the watermark should survive a variety of attacks. However, the autocorrelation peaks are not strong enough. The proposed method improves the robustness of ACF-based watermarking by enhancing the strength of the autocorrelation peaks. Instead of the simple addition of a watermark to an image, the proposed watermark embedder uses the information of an original image more actively during the embedding process, so that the marked image has strong autocorrelation peaks. Experimental results show that the proposed scheme provides better robustness than conventional ACF-based watermarking against a variety of combined geometric-removal attacks.
BINARY IMAGE WATERMARKING THROUGH BLURRING AND BIASED BINARIZATION
Authors: LU HAIPING , SHI YUN Q. , KOT ALEX C. , CHEN LIHUI
Published: January 2005

Digital watermarking has been proposed for the protection of digital medias. This paper presents two watermarking algorithms for binary images. Both algorithms involve a blurring preprocessing and a biased binarization. After the blurring, the first algorithm embeds a watermark by modifying the DC components of the Discrete Cosine Transform (DCT), followed by a biased binarization, and the second one embeds a watermark by directly biasing the binarization threshold of the blurred image, controlled by a loop. Experimental results show the imperceptibility and robustness aspects of both algorithms.
SELF RECOVERY AUTHENTICATION OF IMAGES IN THE DWT DOMAIN
Authors: PIVA ALESSANDRO , BARTOLINI FRANCO , CALDELLI ROBERTO
Published: January 2005

The interest for multimedia contents authentication has recently increased. In particular watermarking-based authentication schemes seem to be offering some advantages with respect to classical cryptography tools (e.g. real content authentication, localization of manipulations, storage format independence, transparency to common signal processing, etc.). In this paper a simple and secure self recovery authentication algorithm which hides an image digest into some DWT subbands of the to be authenticated image is presented. This technique has been designed for video surveillance and/or remote sensing applications. The main goal of this approach is to detect possible malevolent object manipulations undergone by the image (object replacing and/or deletion) by means of a self recovery processing. This valuable characteristic has to be maintained also when an image is processed through an usual and friendly transformation like JPEG compression. Particular care is given to make the scheme robust against innocuous manipulations, and secure against forgery attempts. Experimental results are presented that demonstrate the good performance of the proposed system.
VALUED DEFORMATIONS OF ALGEBRAS
Authors: GOZE MICHEL , REMM ELISABETH
Published: January 2005

We develop a notion of deformations using a valuation ring as a ring of coefficients. This allows us in particular to consider the classical Gerstenhaber deformations of associative or Lie algebras as valued deformations and to solve the equation of deformations in a polynomial framework. We consider also deformations of the enveloping algebra of a rigid Lie algebra and we define valued deformations for some classes of non associative algebras.
MODULAR QFD LATTICES WITH APPLICATIONS TO GROTHENDIECK CATEGORIES AND TORSION THEORIES
Authors: ALBU TOMA , IOSIF MIHAI , TEPLY MARK L.
Published: January 2005

A modular lattice L with 0 and 1 is called quotient finite dimensional (QFD) if [x,1] has no infinite independent set for any x∈L. We extend some results about QFD modules to upper continuous modular lattices by using Lemonnier's Lemma. One result says that QFD for a compactly generated lattice L is equivalent to Condition (C): for every m∈L, there exists a compact element t of L such that t∈[0,m] and [t,m[ has no maximal element. If L is not compactly generated, then QFD and (C) separate into two distinct conditions, which are analyzed and characterized for upper continuous modular lattices. We also extend to upper continuous modular lattices some characterizations of QFD modules with Gabriel dimension. Applications of these results are given to Grothendieck categories and module categories equipped with a torsion theory.
NONCOMMUTATIVE HILBERT RINGS
Authors: KAUCIKAS ALGIRDAS , WISBAUER ROBERT
Published: January 2005

Commutative rings in which every prime ideal is the intersection of maximal ideals are called Hilbert (or Jacobson) rings. This notion was extended to noncommutative rings in two different ways by the requirement that prime ideals are the intersection of maximal or of maximal left ideals, respectively. Here we propose to define noncommutative Hilbert rings by the property that strongly prime ideals are the intersection of maximal ideals. Unlike for the other definitions, these rings can be characterized by a contraction property: R is a Hilbert ring if and only if for all n∈ℕ every maximal ideal [Formula: see text] contracts to a maximal ideal of R. This definition is also equivalent to [Formula: see text] being finitely generated as an [Formula: see text]-module, i.e., a liberal extension. This gives a natural form of a noncommutative Hilbert's Nullstellensatz. The class of Hilbert rings is closed under finite polynomial extensions and under integral extensions.
PHYTOREMEDIATION
Authors: Pilon-Smits Elizabeth
Published: January 2005

Phytoremediation the use of plants and their associated microbes for environmental cleanup , the use of plants and their associated microbes for environmental cleanup, has gained acceptance in the past 10 years as a cost-effective, noninvasive alternative or complementary technology for engineering-based remediation methods. Plants can be used for pollutant stabilization, extraction, degradation, or volatilization. These different phytoremediation technologies are reviewed here, including their applicability for various organic and inorganic pollutants, and most suitable plant species. To further enhance the efficiency of phytoremediation, there is a need for better knowledge of the processes that affect pollutant availability, rhizosphere processes, pollutant uptake, translocation, chelation, degradation, and volatilization. For each of these processes I review what is known so far for inorganic and organic pollutants, the remaining gaps in our knowledge, and the practical implications for designing phytoremediation strategies. Transgenic approaches to enhance these processes are also reviewed and discussed.
PSYCHOSOCIAL FACTORS AND CARDIOVASCULAR DISEASES
Authors: Everson-Rose Susan A. , Lewis Tené T.
Published: January 2005

▪ Abstract  Rapidly accruing evidence from a diversity of disciplines supports the hypothesis that psychosocial factors are related to morbidity and mortality due to cardiovascular diseases. We review relevant literature on (a) negative emotional states, including depression, anger and hostility, and anxiety; (b) chronic and acute psychosocial stressors; and (c) social ties, social support, and social conflict. All three of these psychosocial domains have been significantly associated with increased risk of cardiovascular morbidity and mortality. We also discuss critical pathophysiological mechanisms and pathways that likely operate in a synergistic and integrative way to promote atherogenesis and related clinical manifestations. We conclude by discussing some of the important challenges and opportunities for future investigations.
Stimulation of erythrocyte phosphatidylserine exposure by lead ions
Authors: Kempe Daniela S. , Lang Philipp A. , Eisele Kerstin , Klarl Barbara A. , Wieder Thomas , Huber Stephan M. , Duranton Christophe , Lang Florian
Published: January 2005

Pb+ intoxication causes anemia that is partially due to a decreased life span of circulating erythrocytes. As shown recently, a Ca2+-sensitive erythrocyte scramblase is activated by osmotic shock, oxidative stress, and/or energy depletion, leading to exposure of phosphatidylserine at the erythrocyte surface. Because macrophages are equipped with phosphatidylserine receptors, they bind, engulf, and degrade phosphatidylserine-exposing cells. The present experiments were performed to explore whether Pb+ ions trigger phosphatidylserine exposure of erythrocytes. The phosphatidylserine exposure was estimated on the basis of annexin binding as determined using fluorescence-activated cell sorting (FACS) analysis. Exposure to Pb+ ions [≥0.1 μM Pb(NO3)2] significantly increased annexin binding. This effect was paralleled by erythrocyte shrinkage, which was apparent on the basis of the decrease in forward scatter in FACS analysis. The effect of Pb+ ions on cell volume was virtually abolished, and the effect of Pb+ ions on annexin binding was blunted after increase of extracellular K+ concentration. Moreover, both effects of Pb+ ions were partially prevented in the presence of clotrimazole (10 μM), an inhibitor of the Ca2+-sensitive K+ channels in the erythrocyte cell membrane. Whole cell patch-clamp experiments disclosed a significant activation of a K+-selective conductance after Pb+ ion exposure, an effect requiring higher (10 μM) concentrations, however. In conclusion, Pb+ ions activate erythrocyte K+ channels, leading to erythrocyte shrinkage, and also activate the erythrocyte scramblase, leading to phosphatidylserine exposure. The effect could well contribute to the reported decreased life span of circulating erythrocytes during Pb+ intoxication.
Intestinal and renal adaptation to a low-Pi diet of type II NaPi cotransporters in vitamin D receptor- and 1αOHase-deficient mice
Authors: Capuano Paola , Radanovic Tamara , Wagner Carsten A. , Bacic Desa , Kato Shigeaki , Uchiyama Yasushi , St.-Arnoud René , Murer Heini , Biber Jürg
Published: January 2005

Intake of a low-phosphate diet stimulates transepithelial transport of Pi in small intestine as well as in renal proximal tubules. In both organs, this is paralleled by a change in the abundance of the apically localized NaPi cotransporters NaPi type IIa (NaPi-IIa) and NaPi type IIb (NaPi-IIb), respectively. Low-Pi diet, via stimulation of the activity of the renal 25-hydroxyvitamin-D3-1α-hydroxylase (1αOHase), leads to an increase in the level of 1,25-dihydroxy-vitamin D3 [1,25(OH)2D]. Regulation of the intestinal absorption of Pi and the abundance of NaPi-IIb by 1,25(OH)2D has been supposed to involve the vitamin D receptor (VDR). In this study, we investigated the adaptation to a low-Pi diet of NaPi-IIb in small intestine as well as NaPi-IIa in kidneys of either VDR- or 1αOHase-deficient mice. In both mouse models, upregulation by a low-Pi diet of the NaPi cotransporters NaPi-IIa and NaPi-IIb was normal, i.e., similar to that observed in the wild types. Also, in small intestines of VDR- and 1αOHase-deficient mice, the same changes in NaPi-IIb mRNA found in wild-type mice were observed. On the basis of the results, we conclude that the regulation of NaPi cotransport in small intestine (via NaPi-IIb) and kidney (via NaPi-IIa) by low dietary intake of Pi cannot be explained by the 1,25(OH)2D-VDR axis.
Evolutionary origins of eukaryotic sodium/proton exchangers
Authors: Brett Christopher L. , Donowitz Mark , Rao Rajini
Published: January 2005

More than 200 genes annotated as Na+/H+ hydrogen exchangers (NHEs) currently reside in bioinformation databases such as GenBank and Pfam. We performed detailed phylogenetic analyses of these NHEs in an effort to better understand their specific functions and physiological roles. This analysis initially required examining the entire monovalent cation proton antiporter (CPA) superfamily that includes the CPA1, CPA2, and NaT-DC families of transporters, each of which has a unique set of bacterial ancestors. We have concluded that there are nine human NHE (or SLC9A) paralogs as well as two previously unknown human CPA2 genes, which we have named HsNHA1 and HsNHA2. The eukaryotic NHE family is composed of five phylogenetically distinct clades that differ in subcellular location, drug sensitivity, cation selectivity, and sequence length. The major subgroups are plasma membrane (recycling and resident) and intracellular (endosomal/TGN, NHE8-like, and plant vacuolar). HsNHE1, the first cloned eukaryotic NHE gene, belongs to the resident plasma membrane clade. The latter is the most recent to emerge, being found exclusively in vertebrates. In contrast, the intracellular clades are ubiquitously distributed and are likely precursors to the plasma membrane NHE. Yeast endosomal ScNHX1 was the first intracellular NHE to be described and is closely related to HsNHE6, HsNHE7, and HsNHE9 in humans. Our results link the appearance of NHE on the plasma membrane of animal cells to the use of the Na+/K+-ATPase to generate the membrane potential. These novel observations have allowed us to use comparative biology to predict physiological roles for the nine human NHE paralogs and to propose appropriate model organisms in which to study the unique properties of each NHE subclass.
A compartmental capillary, convolution integration model to investigate nutrient transport and metabolism in vivo from paired indicator/nutrient dilution curves
Authors: Qiao Fulong , Trout Donald R. , Quinton V. Margaret , Cant John P.
Published: January 2005

Thirty-three paired indicator/nutrient dilution curves across the mammary glands of four cows were obtained after rapid injection of para-aminohippuric acid (PAH) plus glucose into the external iliac artery. For the measurement of extracellular volume and kinetics of nutrient uptake from indicator dilution curves, several models of solute dispersion and disappearance have been proposed. The Crone-Renkin models of exchange in a single capillary assume negligible washout of solutes from the extracellular space and do not describe entire dilution curves. The Goresky models include a distribution of capillary transit times to generate whole system outflow profiles but require two indicators to parametize extracellular behavior. A compartmental capillary, convolution integration model is proposed that uses one indicator to account for the extracellular behavior of the nutrient after a paired indicator/nutrient injection. With the use of an iterative approach to least squares, unique solutions for nonexchanging vessel transit time μ and its variance σ were obtained from all 33 PAH curves. The average of heterogeneous vascular transit times was approximated as 2σ = 8.5 s. The remainder of indicator dispersion was considered to be due to washout from a well-mixed compartment representing extracellular space that had an estimated volume of 5.5 liters or 24% of mammary gland weight. More than 99% of the variation in the time course of venous PAH concentration after rapid injection into the arterial supply of the mammary glands was explained in an unbiased manner by partitioning the organ into a heterogeneous nonexchanging vessel subsystem and a well-mixed compartmental capillary subsystem.
Postconditioning Inhibits Mitochondrial Permeability Transition
Authors: Argaud Laurent , Gateau-Roesch Odile , Raisky Olivier , Loufouat Joseph , Robert Dominique , Ovize Michel
Published: January 2005

Background—

Brief periods of ischemia performed just at the time of reperfusion can reduce infarct size, a phenomenon called “postconditioning.” After reflow, opening of the mitochondrial permeability transition pore (mPTP) has been involved in lethal reperfusion injury. We hypothesized that postconditioning may modulate mPTP opening.

Methods and Results—

Anesthetized open-chest rabbits underwent 30 minutes of ischemia and 4 hours of reperfusion. Control hearts underwent no additional intervention. Postconditioning consisted of 4 episodes of 1 minute of coronary occlusion and 1 minute of reperfusion performed after 1 minute of reflow after the prolonged ischemia. Preconditioning consisted of 5 minutes of ischemia and 5 minutes of reperfusion before the 30-minute ischemia. An additional group of rabbits received 5 mg/kg IV of NIM811, a specific inhibitor of the mPTP, 1 minute before reperfusion. Infarct size was assessed by triphenyltetrazolium staining. Mitochondria were isolated from the risk region myocardium, and Ca
2+
-induced mPTP opening was assessed by use of a potentiometric method. Postconditioning, preconditioning, and NIM811 significantly limited infarct size, which averaged 29±4%, 18±4%, and 20±4% of the risk region, respectively, versus 61±6% in controls (
P
≤0.001 versus control). The Ca
2+
load required to open the mPTP averaged 41±4, 47±5, and 67±9 μmol/L CaCl
2
per mg of mitochondrial proteins in postconditioning, preconditioning, and NIM811, respectively, significantly higher than the value of 16±4 μmol/L per mg in controls (
P
≤0.05).

Conclusions—

Postconditioning inhibits opening of the mPTP and provides a powerful antiischemic protection.
Discharge Education Improves Clinical Outcomes in Patients With Chronic Heart Failure
Authors: Koelling Todd M. , Johnson Monica L. , Cody Robert J. , Aaronson Keith D.
Published: January 2005

Background—

Although interventions combining patient education and postdischarge management have demonstrated benefits in patients with chronic heart failure, the benefit attributable to patient education alone is not known. We hypothesized that a patient discharge education program would improve clinical outcomes in patients with chronic heart failure.

Methods and Results—

We conducted a randomized, controlled trial of 223 systolic heart failure patients and compared the effects of a 1-hour, one-on-one teaching session with a nurse educator to the standard discharge process. Subjects were contacted by telephone at 30, 90, and 180 days to collect information about clinical events, symptoms, and self-care practices. The primary end point of the study was the total number of days hospitalized or dead in the 180-day follow-up period. Subjects randomized to receive the teaching session (n=107) had fewer days hospitalized or dead in the follow-up period (0 and 10 days, median and 75th percentiles) than did controls (n=116, 4 and 19 days;
P
=0.009). Patients receiving the education intervention had a lower risk of rehospitalization or death (relative risk, 0.65; 95% confidence interval, 0.45 to 0.93;
P
=0.018). Costs of care, including the cost of the intervention, were lower in patients receiving the education intervention than in control subjects by $2823 per patient (
P
=0.035).

Conclusions—

The addition of a 1-hour, nurse educator–delivered teaching session at the time of hospital discharge resulted in improved clinical outcomes, increased self-care measure adherence, and reduced cost of care in patients with systolic heart failure.
Mesenchymal Stem Cells Differentiate into an Endothelial Phenotype, Enhance Vascular Density, and Improve Heart Function in a Canine Chronic Ischemia Model
Authors: Silva Guilherme V. , Litovsky Silvio , Assad Joao A.R. , Sousa Andre L.S. , Martin Bradley J. , Vela Deborah , Coulter Stephanie C. , Lin Jing , Ober Judy , Vaughn William K. , Branco Rodrigo V.C. , Oliveira Edie M. , He Rumin , Geng Yong-Jian , Willerson James T. , Perin Emerson C.
Published: January 2005

Background—

Bone marrow–derived stem cells are under investigation as a treatment for ischemic heart disease. Mesenchymal stem cells (MSCs) have been used preferentially in the acute ischemia model; data in the chronic ischemia model are lacking.

Methods and Results—

Twelve dogs underwent ameroid constrictor placement. Thirty days later, they received intramyocardial injections of either MSCs (100×10
6
MSCs/10 mL saline) (n=6) or saline only (10 mL) (controls) (n=6). All were euthanized at 60 days. Resting and stress 2D echocardiography was performed at 30 and 60 days after ameroid placement. White blood cell count (WBC), C-reactive protein (CRP), creatine kinase MB (CK-MB), and troponin I levels were measured. Histopathological and immunohistochemical analyses were performed. Mean left ventricular ejection fraction was similar in both groups at baseline but significantly higher in treated dogs at 60 days. WBC and CRP levels were similar over time in both groups. CK-MB and troponin I increased from baseline to 48 hours, eventually returning to baseline. There was a trend toward reduced fibrosis and greater vascular density in the treated group. MSCs colocalized with endothelial and smooth muscle cells but not with myocytes.

Conclusions—

In a canine chronic ischemia model, MSCs differentiated into smooth muscle cells and endothelial cells, resulting in increased vascularity and improved cardiac function.
KRP-203, a Novel Synthetic Immunosuppressant, Prolongs Graft Survival and Attenuates Chronic Rejection in Rat Skin and Heart Allografts
Authors: Shimizu Hisashi , Takahashi Masafumi , Kaneko Takashi , Murakami Takashi , Hakamata Yoji , Kudou Shinji , Kishi Tetsuya , Fukuchi Kazunori , Iwanami Satoru , Kuriyama Kazuhiko , Yasue Tokutaro , Enosawa Shin , Matsumoto Koshi , Takeyoshi Izumi , Morishita Yasuo , Kobayashi Eiji
Published: January 2005

Background—

A novel immunomodulator, KRP-203, the molecular structure of which has some similarity to FTY720, has been developed for use in organ transplantation. The present study was designed to investigate the potency and safety of KRP-203 on allograft survival against both acute and chronic rejection in rat skin and heart transplantation.

Methods and Results—

KRP-203 significantly prolonged skin or heart allograft survival of a minor histocompatibility complex (mHC)–disparate (LEW to F344) rat combination. Histopathological and immunohistochemical analysis at 100 days after mHC-disparate rat heart transplantation revealed that KRP-203 treatment significantly inhibited infiltration of inflammatory cells, including macrophages and T cells; expression of endothelin-1 and transforming growth factor-β
1
; and IgG deposition and eventually attenuated neointimal formation and myocardial fibrosis. KRP-203 also prolonged heart allograft survival in a major histocompatibility complex (MHC)-incompatible (DA to LEW) rat combination, but the efficacy was not as significant. However, KRP-203 combined with a subtherapeutic dose of cyclosporin A synergistically prolonged the heart allograft survival. Flow cytometric analysis demonstrated that KRP-203 reduced the number of peripheral blood mononuclear cells (lymphocytes and monocytes) but not granulocytes and enhanced lymphocyte homing into peripheral lymph nodes. The influence of KRP-203 on heart rate changes in Hartley guinea pigs was examined. KRP-203 had less of a tendency to cause bradycardia than FTY720.

Conclusions—

These findings demonstrated that KRP-203 prolonged skin and heart allograft survival and significantly attenuated chronic rejection and bradycardia as an adverse effect. Therefore, KRP-203 offers considerable potential as a novel therapeutic immunosuppressant in patients with organ transplantation.
Role of β
2
Adrenergic Receptors in Human Atherosclerotic Coronary Arteries
Authors: Barbato Emanuele , Piscione Federico , Bartunek Jozef , Galasso Gennaro , Cirillo Plinio , De Luca Giuseppe , Iaccarino Guido , De Bruyne Bernard , Chiariello Massimo , Wijns William
Published: January 2005

Background—

Adrenergic regulation of coronary vasomotion is balanced between α
1
-adrenergic–mediated (α
1
-AR) constriction and β
2
-adrenergic–mediated (β
2
-AR) relaxation. This study aimed at assessing the role of β
2
-ARs in normal, mildly atherosclerotic, and stenotic human coronary arteries.

Methods and Results—

During intracoronary (IC) infusion of increasing doses of the β
2
-AR agonist salbutamol (0.15, 0.3, and 0.6 μg/min) and the endothelial vasodilator acetylcholine (1, 3, and 10 μg/min), we measured (1) changes in lumen diameter (LD) by quantitative coronary angiography in 34 normal, 55 mildly atherosclerotic, and 42 stenotic coronary artery segments and (2) changes in average peak velocity (APV) and coronary blood flow (CBF) with the use of Doppler flow wire in 11 normal, 10 mildly atherosclerotic, and 11 stenotic coronary arteries. In 6 of 11 stenotic coronary arteries, the protocol was repeated after an IC bolus (12 μg/kg) of the α-adrenergic blocker phentolamine. In 6 of 11 normal coronary arteries, the protocol was repeated after an IC infusion (60 μmol/min) of
N
G
-monomethyl-
l
-arginine (L-NMMA), a nitric oxide inhibitor. Neither salbutamol IC infusion nor acetylcholine significantly changed heart rate or blood pressure, whereas L-NMMA slightly increased blood pressure. In normal coronary arteries, salbutamol increased LD (LD max %: 11±2,
P
<0.05), APV (APV max %: 53±17,
P
<0.05), and CBF (CBF max %: 57±17,
P
<0.05), whereas L-NMMA caused a blunted APV (APV max %: 27±6,
P
<0.05) and CBF (CBF max %: 29±6,
P
<0.05) response to salbutamol. In mildly atherosclerotic coronary arteries, the salbutamol increase in LD (LD max %: 10±2,
P
<0.05), APV (APV max %: 33±12,
P
<0.05), and CBF (CBF max %: 37±12,
P
<0.05) was preserved. In stenotic coronary arteries, salbutamol induced a paradoxical reduction in LD (LD max %: −6±2,
P
<0.05), APV (APV max %: −15±9,
P
<0.05), and CBF (CBF max %: −15±6,
P
<0.05), which was no longer observed after phentolamine. Acetylcholine increased LD (LD max %: 14±3,
P
<0.05), APV (APV max %: 61±20,
P
<0.05), and CBF (CBF max %: 67±19,
P
<0.05) in normal coronary arteries. In mildly atherosclerotic coronary arteries, acetylcholine induced a significant reduction in LD (LD max %: −15±2,
P
<0.05) and no changes in APV (APV max %: −6±13,
P
=NS) and CBF (CBF max %: −10±13,
P
=NS). In stenotic coronary arteries, acetylcholine significantly reduced LD (LD max %: −15±3,
P
<0.05), APV (APV max %: −15±9,
P
<0.05), and CBF (CBF max %: −15±6,
P
<0.05).

Conclusions—

In severely atherosclerotic coronary arteries, β
2
-adrenergic vasodilatation is impaired, and this might contribute to alter the vasomotor balance, further precipitating myocardial ischemia during sympathetic activation.
Tissue Factor Cytoplasmic Domain Stimulates Migration by Activation of the GTPase Rac1 and the Mitogen-Activated Protein Kinase p38
Authors: Ott Ilka , Weigand Berthold , Michl Ruth , Seitz Isabell , Sabbari-Erfani Nooshin , Neumann Franz-Josef , Schömig Albert
Published: January 2005

Background—

Tissue factor (TF), the surface receptor for the serine protease factor VIIa (FVIIa) and the initiator of the extrinsic coagulation cascade, supports vessel development and tumor metastasis by activation of extracellular, protease-dependent signaling pathways. The molecular mechanisms that do not require proteolytic activity of FVIIa are not yet known. The aim of the study, therefore, was to investigate the effects of active-site–inhibited FVIIa (FFR-FVIIa) on TF-mediated signaling.

Methods and Results—

After stimulation with FVIIa and FFR-FVIIa, migration and activation of the GTPase Rac (Rac1) or the mitogen-activated protein kinase p38 (p38) were analyzed in J82 cells. FVIIa and FFR-FVIIa stimulated migration and activation of Rac1 and p38 in a TF-specific, dose- and time-dependent manner. Enhancement of migration required activation of Rac1 and p38, because it was abolished after inhibition with SB203580 or overexpression of dominant negative p38 and Rac1. The cytoplasmic domain of TF was necessary because no effects of FFR-FVIIa could be detected after transfection of a TF deletion mutant lacking the cytoplasmic domain.

Conclusions—

We identified a novel signaling pathway through which TF stimulates migration by activation of p38 and Rac1 independent of the proteolytic activity of FVIIa but dependent on the cytoplasmic domain of TF. Binding of FFR-VIIa to TF may stimulate vessel wall remodeling by enhancement of migration through activation of Rac1 and p38. This novel link may provide an insight into the understanding of the nonhemostatic functions of TF.
Different Contributions of Endothelin-A and Endothelin-B Receptors in Postischemic Cardiac Dysfunction and Norepinephrine Overflow in Rat Hearts
Authors: Yamamoto Satoshi , Matsumoto Noriko , Kanazawa Mitsuo , Fujita Marie , Takaoka Masanori , Gariepy Cheryl E. , Yanagisawa Masashi , Matsumura Yasuo
Published: January 2005

Background—

Endothelin (ET)-1 and norepinephrine (NE) are involved in myocardial ischemia/reperfusion injury. We investigated the role of ET-1 in ischemia/reperfusion–induced NE overflow and cardiac dysfunction using a selective ET
A
receptor antagonist (ABT-627), a selective ET
B
receptor antagonist (A-192621), and the spotting lethal (
sl
) rat, which carries a naturally occurring deletion in the ET
B
receptor gene.

Methods and Results—

According to the Langendorff technique, isolated hearts were subjected to 40-minute global ischemia followed by 30-minute reperfusion. In Sprague-Dawley rat hearts, ischemia/reperfusion–induced cardiac dysfunctions such as decreased left ventricular developed pressure and coronary flow and increased left ventricular end-diastolic pressure were worsened by treatment with A-192621. This agent enhanced excessive NE overflow in the coronary effluent from the postischemic heart. In contrast, treatment with ABT-627, in the absence or presence of A-192621, significantly improved postischemic cardiac dysfunction and markedly suppressed NE overflow to the same extent. Postischemic cardiac dysfunction and NE overflow in the heart of ET
B
receptor–deficient homozygous (
sl
/
sl
) rats were highly observed compared with cases in wild-type rats, and exaggerated responses to ischemia/reperfusion in
sl
/
sl
rats were abolished by ABT-627 treatment. Exogenously applied ET-1 produced severe cardiac dysfunction and a significant increase in NE overflow in a dose-dependent manner, but these responses were markedly suppressed in the presence of 5-
N
-ethyl-
N
-isopropyl-amiloride, an inhibitor of the Na
+
/H
+
exchanger (NHE).

Conclusions—

Pharmacological blockade or genetic deficiency of ET
B
receptors is detrimental to the postischemic heart, and exaggerated cardiac pathology under the above conditions is mediated by ET
A
receptor activation. ET
A
/NHE-mediated excessive NE overflow is contributive, at least in part, to postischemic cardiac dysfunction in rats.
Mechanisms of Angiotensin II–Mediated Decreases in Intraneuronal Ca
2+
in Calcium-Loaded Stellate Ganglion Neurons
Authors: Fernandez Stanley F. , Huang Ming-He , Davidson Bruce A. , Knight Paul R , Izzo Joseph L.
Published: January 2005

Our laboratory has reported previously that angiotensin II, type-1 (AT
1
) receptor stimulation in isolated stellate ganglion neurons decreases intraneuronal calcium concentration ([Ca
2+
]i) acutely if baseline [Ca
2+
]i is high and increases [Ca
2+
]i if baseline [Ca
2+
]i is low. Part of the angiotensin II (Ang II) effect in high Ca
2+
neurons is mediated through stimulation of Na
+
–Ca
2+
exchange. Current experiments were conducted to identify additional steps in the signaling pathways. In Ca
2+
-loaded neurons, Ang II–induced decreases in [Ca
2+
]i were attenuated by phospholipase C inhibition (U73122) or nitric oxide (NO) synthase inhibition (
l
-NMMA) and were mimicked by the cGMP analogue 8-Br-cGMP. Protein kinase C (PKC) inhibition (bisindolylmaleimide I or Go6976) and protein kinase G (PKG) inhibition (KT5823) partially blocked Ang II–mediated decreases in [Ca
2+
]i, but complete blockade of Ang II effects was obtained with combined PKC and PKG inhibition. Modulation of inositol triphosphate (IP
3
)-inducible ER Ca
2+
release by [Ca
2+
]i was investigated using furaptra, an ER-retaining dye. IP
3
-mediated ER Ca
2+
release in β-escin–permeabilized neurons was measured after clamping of [Ca
2+
]i from 50 nM to 800 nM. Maximal ER Ca
2+
release was observed at ≈200 nM [Ca
2+
]i, with noted blunting of release at higher [Ca
2+
]i. Steady-state mRNA transcript and protein levels revealed that the principal IP
3
R isoform expressed was IP
3
R-II. These results suggest that Ca
2+
loading in stellate ganglion neurons promotes Ang II-mediated decreases in [Ca
2+
]i via PKC and NO/cGMP/PKG pathways and inhibits IP
3
R-II–mediated ER Ca
2+
release.
Sleep Deprivation Potentiates Activation of Cardiovascular and Catecholamine Responses in Abstinent Alcoholics
Authors: Irwin Michael R. , Ziegler Michael
Published: January 2005

Alcohol dependence is associated with an increased incidence of hypertension and cardiac arrhythmias, but the triggering mechanisms are not known. Sleep loss, common in alcohol-dependent patients, causes an activation of the sympathetic nervous system. To determine whether sleep deprivation induces differential cardiovascular and sympathetic responses in alcohol dependence, we measured heart rate, blood pressure, and circulating sympathetic catecholamines in 36 abstinent alcohol-dependent men and 36 age-, gender-, and ethnicity-matched controls after a baseline night of sleep, in the morning after early night partial sleep deprivation, and again after a full night of recovery sleep. Subjects were on average normotensive and none was being treated for hypertension. Baseline heart rate, blood pressure, and sympathetic catecholamines were similar in the 2 groups. Administration of partial night sleep deprivation induced greater increases of heart rate (
P
<0.01) and circulating levels of norepinephrine (
P
<0.05) and epinephrine (
P
<0.05) in the alcohol-dependent men as compared with responses in controls. Even after a full night of recovery sleep, elevations in heart rate (
P
<0.05) and circulating catecholamines (
P
<0.05) persisted in the alcoholic subjects. Partial night sleep deprivation induces elevated heart rate and sympathetic catecholamine responses in alcoholic subjects as compared with controls, and this sympathetic activation is sustained after nights of partial and recovery sleep. It is possible that modest habitual sleep loss could contribute to triggering cardiac arrhythmias or other cardiovascular events in alcohol dependence.
Evaluation of Carotid-Femoral Pulse Wave Velocity
Authors: Millasseau Sandrine C. , Stewart Andrew D. , Patel Sundip J. , Redwood Simon R. , Chowienczyk Philip J.
Published: January 2005

Carotid-femoral pulse wave velocity (PWV), a measure of arterial stiffness, is determined from the time taken for the arterial pulse to propagate from the carotid to the femoral artery. Propagation time is measured variously from the foot of the waveform or point of maximum upslope. We investigated whether these methods give comparable values of PWV at rest, during β-adrenergic stimulation, and pacing-induced tachycardia. In subjects at rest (n=43), values obtained using the foot-to-foot method (SphygmoCor system) were 1.7±0.75 m/s (mean±SD) greater than those obtained using the maximum slope (Complior system) at a mean value of 12 m/s. Isoprotenerol (0.5 to 1.5 μg/min; n=10), and pacing (in subjects with permanent pacemakers; n=11) increased heart rate but had differential effects on systolic blood pressure and pulse pressure. The increase in heart rate produced by isoprotenerol (18±3 bpm) and pacing (40 bpm) was associated with an increase in PWV measured using both systems (increases of 0.7±0.2 m/s and 0.9±0.2 m/s for SphygmoCor and Complior, respectively, during isoprotenerol and increases of 2.1±0.5 m/s and 1.1±0.2 m/s for SphygmoCor and Complior, respectively, during pacing, each
P
<0.001). Reanalysis of waveforms recorded from the Complior system using the foot-to-foot method produced similar values of PWV to those obtained with the SphygmoCor, confirming that the difference between these systems was attributable to the timing algorithm rather than other aspects of signal acquisition. Carotid-femoral PWV is critically dependent on the method used to determine propagation time, but this does not account for variation of PWV with heart rate.
‘La société était au fond légitimiste’: Émigrés, Aristocracy, and the Court at Vienna, 1789-1848
Authors: Godsey William D.
Published: January 2005

The House of Austria had a long tradition dating back at least to the Thirty Years War of accepting foreign nobles, regardless of origin, into its service. During the wars of the French Revolution and Napoleon, this tradition received renewed impetus. A relatively small, but highly visible, group of émigrés from France, the southern Netherlands, and the left bank of the Rhine gained admission on the basis of birth to Court at Vienna and eventually integrated permanently with the great Hapsburg aristocracy. By the late nineteenth century, the paternal ancestors of no less than ten per cent of Austrian aristocratic families had first settled in the Monarchy after 1789. These émigrés -aristocrats and their immediate descendants came to occupy many prominent positions in the highest echelons at Court, in the diplomatic service, and in the military. Almost alone among western and central European nobilities, the Hapsburg aristocracy had not been directly hit by revolutionary change. Yet its easy absorption of émigrés represented a remarkable social and cultural transformation that was not without political ramifications as well.
Informalization in UK party election broadcasts 1966-97
Authors: Pearce Michael
Published: January 2005

This article uses a novel, quantitatively based method to assess the extent to which UK party election broadcasts in the 31 years between 1966 and 1997 became more ‘informal’. Using the Longman Grammar of Spoken and Written English, I identify 28 linguistic ‘markers’ which are salient in the assessment of formality, and count their frequencies in the 37,000-word corpus. My quantitative findings reveal a general increase in informalization over time, which corresponds with judgements made in critical discourse analysis (CDA). But I also discover an anomaly in the broadcasts from 1987, which I explain with reference to the influence of the Conservative party leader, Margaret Thatcher.
The influence of social environment on internet connectedness of adolescents in Seoul, Singapore and Taipei
Authors: Jung Joo-Young , Kim Yong-Chan , Lin Wan-Ying , Cheong Pauline Hope
Published: January 2005

This article examines the influence of the social environment on adolescents’ connectedness to the internet in East Asia, one of the most wired regions in the world. Connectedness is a qualitative conceptualization of an individual’s relationship with the internet, taking into consideration the breadth, depth, and the importance of individuals’ internet experience. This study seeks to situate adolescents’ internet connectedness in three spheres of social environment: (1) the general social support measured by how easy it is to get help when adolescents encounter problems in using the internet; (2) the parents, where we examine parents’ socioeconomic status and their internet use; and (3) the peer group, where we look into the proportion of friends who connect to the internet. The results from a survey of 1303 adolescents in Seoul, Singapore and Taipei support our major hypothesis that among the internet-using adolescents, their internet connectedness patterns differ by the nature of their social environments.
Considering spiritual dimensions within computer-mediated communication studies
Authors: Campbell Heidi
Published: January 2005

This article explores how the internet is being studied and conceived of as a sacramental space. The internet as sacramental space demonstrates how religious users see the internet as a viable place for presenting their beliefs and practices. In order to understand this model, several other dominant conceptions of the internet are offered: information space, a common mental geography, an identity workshop and a social space. Each of these accents a specific use of the internet. The internet as sacramental space is further investigated by considering several typologies of online spiritual communities emerging from a recent online community study. Each typology highlights how the internet as sacramental space encompasses traits of the previously stated models and illustrates how the internet is used as a spiritual tool, religious identity, a space for personal spiritual pursuits and a social spiritual support sphere. A survey of current CMC research on religion is also presented.
Qualitative research as partial connection: bypassing the power-knowledge nexus
Authors: Jensen Casper , Lauritsen Peter
Published: January 2005

Qualitative research and methods are often imagined as relating to a problematic, which we here term the power-knowledge nexus. We argue that the dichotomy between power and knowledge, instantiated, for example, by recent postmodern contributions to the field, is theoretically and empirically problematic and suggest that they are organized around a ‘bad problem’ (Deleuze, 1991). This characterization points us towards an exploration of theoretical and practical consequences entailed by the suspension of the powerknowledge nexus. We suggest that there is a need for a renewed consideration of the capacities of qualitative research. We initiate such discussion by drawing on insights and illustrations from contemporary feminist theory and science and technology studies (STS).
Gazing with intent: ethnographic practice in classrooms
Authors: Gordon Tuula , Holland Janet , Lahelma Elina , Tolonen Tarja
Published: January 2005

In this methodological article we discuss ways in which researchers observe girls and boys in the classroom. The article is based on a comparative cross-cultural, collective ethnographic study, ‘Citizenship, Difference and Marginality in Schools: With Special Reference to Gender’, which was conducted in secondary schools in Helsinki and London. When we analysed our own actions, we realized that educational researchers – like teachers – tend to concentrate on events taking place in the classroom, particularly visible and audible action. They are less likely to direct their gaze on stillness and silence. In most of the classes that we followed, boys used more voice, time, space and movement than girls, although there were also differences among girls and among boys. In the early stages of our study, noisy and physically active boys drew our attention. But in our practice as the research continued, and in this article, we turn our gaze onto non-events, and ask reflexive researchers to problematize their categories of active and passive. Drawing from our own observations, we discuss how activity, passivity and agency are conceptualized and gendered in educational research.
Bone wax cast to repair a cannula leakage during prolonged extracorporeal membrane oxygenation
Authors: Zwischenberger Joseph B , Girouard Mark , Lynch James E
Published: January 2005

During prolonged extracorporeal perfusion, thin-walled wire-wound cannulas have become the standard for low resistance cannula access for extrathoracic cannulation. We present an unusual technique of bone wax casting to repair a leak in a cannula to continue long-term extracorporeal membrane oxygenation.
Carotid Doppler microembolic signals in patients one year after heart valve surgery
Authors: Dalinin Vadim , Lingaas Per Snorre , Hatteland Kjell , Svennevig Jan L
Published: January 2005

Doppler ultrasound has been used to detect microemboli during and after cardiopulmonary bypass (CPB). The aim of the present study was to examine the frequency of microembolic signals (MES) in patients one year after heart valve replacement, to look for possible risk factors associated with MES and for any correlation with cerebral events. One hundred patients, 69 male and 31 female, mean age 66.3±12.4 years, were examined one year after heart valve replacement. Thirty patients, 61% male and 39% female, mean age 62.5±8.7 years, who had undergone cardiovascular operations without heart valve pathology served as controls. A newly developed micro-emboli detector, EMEX-25 (Hatteland Instrumentering, Norway) was used to detect MES from both carotid arteries. MES were detected in 61% of the valve patients. A correlation was found between the number of MES, previous cardiovascular operations, emergency surgery and EuroSCORE ( p<0.05). There was no correlation between the number of MES and the level of anticoagulation expressed as international normalization ratio (INR), atrial fibrillation, serum-cholesterol, New York heart association (NYHA) class, gender, age, valve type or valve position. The average number of MES was not increased in seven patients who had experienced major (three) or minor (transient, four) cerebral events during follow-up. In the 30 nonvalve controls, MES were detected in 46% of the patients. MES were detected in valve patients as well as in nonvalve patients one year after surgery. In valve patients, a significant correlation was found between MES and previous surgery, emergency surgery and EuroSCORE. There was no correlation between the number of MES and INR level or postoperative cerebral events.