bluuebunny/crossref_metadata_2025 huggingface dataset:
BIPHASIC OPTICAL SIGNAL OF AN OSCILLATING NONSTATIONARY BELOUSOV–ZHABOTINSKY BULK REACTION AND ITS SIMILARITY TO SOME NEUROPHYSIOLOGICAL EVENTS
Authors: DOLZMANN K. , KALTENBACH S. , HANKE W. , FERNANDES DE LIMA V. M.
Published: June 2007

Oscillating chemical bulk reactions of the Belousov–Zhabotinsky (BZ) type usually show a well-defined periodical color change representing the underlying chemical reactions. Models including up to more than 50 coupled reactions have been developed to describe the BZ-reaction in detail, however, typically a much simpler set of equations is used (i.e. the Brüsselator, the FKN, or the FitzHugh–Nagumo model). There are various types of oscillating reactions with color changes, for example, from transparent to yellow ( Ce catalyzed), or from blue to red (Ferroin catalyzed). In equilibrium systems and in models each color-change is usually a simple curve with one maximum, and the oscillation is stable in time.

We have investigated the detailed structure of the intrinsic optical signal (IOS) of a BZ-reaction in-depth andfound, in a nonstationary ferroin catalyzed BZ-reaction, a much more complex optical behavior.

Amazingly, this IOS with its detailed time dependence very much resembles electrical and optical signals from important neuronal processes. These are especially the sodium current during action potentials (AP) and the retinal spreading depression (SD). The time-scale of all these processes can be different by decades. This principal similarity, however, points to a deeper common theoretical basis of all these processes as assumed up to now, and makes the presented type of BZ-reaction an ideal model for a variety of neurophysiological signals, although the mechanisms are strictly different.
PROJECTIVE SYNCHRONIZATION VIA A LINEAR OBSERVER: APPLICATION TO TIME-DELAY, CONTINUOUS-TIME AND DISCRETE-TIME SYSTEMS
Authors: GRASSI GIUSEPPE , MILLER DAMON A.
Published: June 2007

This Letter presents a general approach to projective synchronization that features a linear observer with an ability to arbitrarily scale a drive system attractor. The technique can be applied to wide classes of chaotic and hyperchaotic systems, namely time-delay systems described by functional differential equations (FDEs), continuous-time systems described by ordinary differential equations (ODEs) and discrete-time systems described by difference equations (DEs). Theoretical and simulation results demonstrate that a linear observer can duplicate chaotic system states in any desired scale using only a scalar synchronizing signal. The proposed approach is readily implemented in hardware.
STABILITY AND HOPF BIFURCATION ON A TWO-NEURON SYSTEM WITH TIME DELAY IN THE FREQUENCY DOMAIN
Authors: YU WENWU , CAO JINDE
Published: June 2007

In this paper, a general two-neuron model with time delay is considered, where the time delay is regarded as a parameter. It is found that Hopf bifurcation occurs when this delay passes through a sequence of critical value. By analyzing the characteristic equation and using the frequency domain approach, the existence of Hopf bifurcation is determined. The stability of bifurcating periodic solutions are determined by the harmonic balance approach, Nyquist criterion and the graphic Hopf bifurcation theorem. Numerical results are given to justify the theoretical analysis.
THE TROUBLE WITH SPURIOUS EIGENVALUES
Authors: ADOMAITIS RAYMOND A.
Published: June 2007

Stability analysis of spatially discretized approximations to invariant circle solutions to a noninvertible map is shown to produce seemingly spurious eigenvalues, found to exist for all truncation numbers. Numerical analysis of the spectral Galerkin projection procedure used to compute the solutions and the eigenvalues of the linearization shows that the set of discrete eigenvalues converges in terms of its mean value. Further analysis shows that the spurious eigenvalues — those that are farthest from the mean value — correspond to eigenfunctions which produce the largest residual in the eigenvalue problem used to compute the eigenvalues and eigenfunctions.
STUDIES OF SUPERHEAVY ELEMENTS AT SHIP
Authors: HOFMANN S. , ACKERMANN D. , ANTALIC S. , BURKHARD H. G. , COMAS V. F. , DRESSLER R. , GAN Z. , HEINZ S. , HEREDIA J. A. , HEßBERGER F. P. , KHUYAGBAATAR J. , KINDLER B. , KOJOUHAROV I. , KUUSINIEMI P. , LEINO M. , LOMMEL B. , MANN R. , MÜNZENBERG G. , NISHIO K. , POPEKO A. G. , SARO S. , SCHÖTT H. J. , STREICHER B. , SULIGNANO B. , UUSITALO J. , YEREMIN A. V.
Published: June 2007

An overview of present experimental investigation of superheavy elements is given. The data are compared with theoretical descriptions. Results are reported from an experiment to confirm production of element 112 isotopes in irradiation of 238 UF 4 with 48 Ca . One spontaneous fission event was measured, which agrees with three events of previously measured data which had been assigned to the decay of 283112. However, more experimental work is needed in order to obtain an independent and unambiguous confirmation of previous results.
FIFTY YEARS OF DISCOVERIES IN NUCLEAR STRUCTURE
Authors: HAMILTON J. H. , RAMAYYA A. V.
Published: June 2007

The complementary nature of the Vanderbilt experimental work and the theoretical work of the Frankfurt group on the rotation-vibration model, the generalized collective model, shape coexistence and cluster radioactivity is described. Recent discoveries in neutron-rich nuclei γ-vibrational bands compared with RVM and GCM are presented. Ultimate examples of cluster radioactivity in cold binary and ternary fission are discussed. Finally, we present evidence for the evolution from axial symmetry in 101 Y to maximum triaxialilty in 113 Rh and for chiral doublet bands in neutron-rich triaxial even-even nuclei between A =106 - 112.
SELF-CONSISTENT MEAN-FIELD MODELS FOR NUCLEAR STRUCTURE AND DYNAMICS
Authors: KLÜPFEL P. , REINHARD P.-G.
Published: June 2007

We discuss the performance and applicability of self-consistent mean-field models for nuclear structure and dynamics taking reference to the relativistic mean-field model (RMF) and mainly to the Skyrme-Hartree-Fock method (SHF). After a very brief summary of the basics, we exemplify the status and future perspective in terms of a few selected key applications, neutron radii, level schemes, fission, resonance excitations, and soft modes.
NUCLEAR MOLECULES
Authors: ADAMIAN G. G. , ANTONENKO N. V. , JOLOS R. V. , IVANOVA S. P. , PALCHIKOV YU. V. , SHNEIDMAN T. M. , ANDREEV A. , SCHEID W.
Published: June 2007

The concept of a nuclear molecule or a dinuclear system assumes two touching nuclei which carry out motion in the internuclear distance and exchange nucleons by transfer. The corresponding model can be applied to nuclear structure, to fusion reactions leading to superheavy nuclei and to multi-nucleon transfer.
CONTINUUM SPECTROSCOPY OF HALO NUCLEI
Authors: VAAGEN J. S. , DANILIN B. V. , ERSHOV S. N.
Published: June 2007

Halo nuclei represent a new type of structure found in extremely neutron rich light nuclei, at the limits of nuclear existence. Of particular interest are Borromean nuclei, where none of the binary substructures can bind. Similar structures, Efimov states, have now also been produced in traps in molecular physics. Nuclear physics has in recent years taken further steps to also explore the nature of the halo continuum, in fact the major part of the spectrum since halo nuclei support only one or a few bound states. Since 3 → 3 scattering is prohibitively difficult to perform, the halo continuum has so far been excited in binary collisions, proceeding via the exotic ground state which to various degrees puts its imprint on the result. Below we discuss via examples how to disentangle continuum structures, comparing with recent correlation data. The work involves a consistent treatment of halo structure and reaction theory, and emphasizes the important future role of exclusive observables and complete experiments.
MODEL OF BINDING ALPHA-PARTICLES AND STRUCTURE OF THE LIGHT NUCLEI
Authors: GRIDNEV K. A. , YU. TORILOV S. , KARTAVENKO V. G. , GREINER W.
Published: June 2007

The model of light nuclei built from alpha particles is considered from the point of view of quasimolecular structure. Some properties of nuclei like binding energy, rotational bands and even Bose-Einstein condensation have simple semiclassical explanation in the framework of this model.
JURASSIC (TRI) QUARK: AN ANGULAR DISTRIBUTION MODEL FOR HEAVY ION REACTIONS
Authors: BLANN MARSHALL
Published: June 2007

Double differential neutron emission spectra are calculated assuming initial directions and energies result from random angle coupling of beam energy and projectile Fermi momenta. Results are compared with data of Holub et al. for 300 MeV 12C+165Ho.The energy distributions resulting from the random angle assumption are compared with results of the exciton formula for A - 1 degrees of freedom, where A is the projectile mass number.
A FAIR CHANCE FOR SUPERNOVAE
Authors: LANGANGKE KARLHEINZ , MARTÍNEZ-PINEDO G.
Published: June 2007

Nuclear physics plays an essential role in the dynamics of a type II supernova (a collapsing star). Recent advances in nuclear many-body theory allow now to calculate the stellar weak-interaction processes involving nuclei. The most important process is the electron capture on finite nuclei with mass numbers A > 55. This process is the source of neutrinos during the collapse phase. Neutrino-nucleus reactions play an interesting role during the collapse and the supernova nucleosynthesis.
EXOTIC NUCLEI IN SUPERNOVAE
Authors: MISHUSTIN IGOR N.
Published: June 2007

In this talk I discuss properties of hot stellar matter at sub-nuclear densities which is formed in supernova explosions. I emphasize that thermodynamic conditions in this case are rather similar to those created in the laboratory by intermediate-energy heavy-ion collisions. Theoretical methods developed for the interpretation of multi-fragment final stats in such reactions can be used also for description of the stellar matter. I present main steps of the statistical approach to the equation of state and nuclear composition, dealing with an ensemble of nuclear species instead of one "average" nucleus. Finally some results of this approach are presented. The emphasis is put on possible formation of heavy and superheavy nuclei.
ULTRA-DENSE NEUTRON STAR MATTER, STRANGE QUARK STARS, AND THE NUCLEAR EQUATION OF STATE
Authors: WEBER FRIDOLIN , MEIXNER MATTHEW , NEGREIROS RODRIGO P. , MALHEIRO MANUEL
Published: June 2007

With central densities way above the density of atomic nuclei, neutron stars contain matter in one of the densest forms found in the universe. Depending of the density reached in the cores of neutron stars, they may contain stable phases of exotic matter found nowhere else in space. This article gives a brief overview of the phases of ultra-dense matter predicted to exist deep inside neutron stars and discusses the equation of state (EoS) associated with such matter.
FOUNDATION AND RESULTS OF A COSMOLOGY WITHOUT BIG BANG ON THE BASIS OF THE PROJECTIVE UNIFIED FIELD THEORY
Authors: SCHMUTZER ERNST
Published: June 2007

After a short introduction into the Projective Unified Field Theory developed by the author during the last decades this theory is applied to a closed homogenous isotropic 2-component cosmos model, based on a mixture of a mechanical particle (urparticle) gas and a photon gas. The field equations lead to three nonlinear differential equations for the temporal course of the world radius, the scalaric world function and the mechanical energy density of the cosmos. These equations were solved numerically and evaluated in detail. The results are presented for a series of important cosmological quantities: world radius, world age, cosmological frequency shift and Hubble parameter, deceleration parameter, mechanical mass density, photon mass density, mechanical pressure, electromagnetic radiation pressure, kinetic particle temperature, electromagnetic radiation (microwave background) temperature, mechanical particle number density, photon number density, etc. Specific results of the theory are: explanation of the time dependence of the Newton gravitational constant, scalaric cosmological heat production in moving celestial bodies and the numerical value of the mass of an urparticle.
CHARGED PARTICLE THERAPY STEPS INTO THE CLINICAL ENVIRONMENT
Authors: HABERER TH.
Published: June 2007

Beams of heavy charged particles like protons or carbon ions represent the ideal tool for the treatment of deep-seated, inoperable and radioresistant tumors. For more than 4 decades research with beams of charged particles has been performed. In total more than 40000 patients have been treated, mostly using protons being delivered by accelerators that were designed for basic research centers. In Berkeley, USA heavier particles like helium or neon ions were used to conduct clinical trials until 1992. Based on that somewhat limited technological standard and triggered by the promising results from Berkeley the first dedicated charged particle facilities were constructed. In order to maximally exploit the advantageous physical and radiobiological characteristics of these beams enormous effort was put into developing dynamic beam delivery techniques and tailoring the capabilities of the accelerators, the planning systems and the quality assurance procedures and equipment to the requirements resulting from these new treatment modalities. Active beam delivery systems integrated in rotating gantries, if necessary, will allow the production of superior dose distributions that precisely follow the medical prescription. The technological progress being made during the last 10 years defines the state of the art of the upcoming next-generation facilities for the clinical environment in Europe and Japan.
ENERGY-DEPENDENT MANY-BODY PERTURBATION THEORY: A ROAD TOWARDS A MANY-BODY-QED PROCEDURE
Authors: LINDGREN INGVAR , SALOMONSON STEN , HEDENDAHL DANIEL
Published: June 2007

A rigorous procedure for energy-dependent many-body perturbation theory (MBPT) is presented. This can be applied for numerical evaluation of many-body-QED effects by combining QED with electron correlation to arbitrary order. So far, it has been used only for the exchange of a single retarded photon together with an arbitrary number of instantaneous Coulomb interactions. For heliumlike neon this represents more than 99% of the nonradiative effect on the energy beyond standard MBPT.
l-PARTS OF DIVISOR CLASS GROUPS OF CYCLIC FUNCTION FIELDS OF DEGREE l
Authors: WITTMANN CHRISTIAN
Published: June 2007

Let l be a prime number and K be a cyclic extension of degree l of the rational function field 𝔽q(T) over a finite field of characteristic ≠ = l. Using class field theory we investigate the l-part of Pic 0(K), the group of divisor classes of degree 0 of K, considered as a Galois module. In particular we give deterministic algorithms that allow the computation of the so-called (σ - 1)-rank and the (σ - 1)2-rank of Pic 0(K), where σ denotes a generator of the Galois group of K/𝔽q(T). In the case l = 2 this yields the exact structure of the 2-torsion and the 4-torsion of Pic 0(K) for a hyperelliptic function field K (and hence of the 𝔽q-rational points on the Jacobian of the corresponding hyperelliptic curve over 𝔽q). In addition we develop similar results for l-parts of S-class groups, where S is a finite set of places of K. In many cases we are able to prove that our algorithms run in polynomial time.
AVERAGE SIZE OF GAPS IN THE FOURIER EXPANSION OF MODULAR FORMS
Authors: ALKAN EMRE
Published: June 2007

We prove that certain powers of the gap function for the newform associated to an elliptic curve without complex multiplication are "finite" on average. In particular we obtain quantitative results on the number of large values of the gap function.
UNE MINORATION POUR L'EXPOSANT DU GROUPE DES CLASSES D'UN CORPS ENGENDRÉ PAR UN NOMBRE DE SALEM
Authors: AMOROSO FRANCESCO
Published: June 2007

In this article we extend the main result of [2] concerning lower bounds for the exponent of the class group of CM-fields. We consider a number field K generated by a Salem number α. If k denotes the field fixed by α ↦ α-1 we prove, under the generalized Riemann hypothesis for the Dedekind zeta function of K, lower bounds for the relative exponent eK/k and the relative size hK/k of the class group of K with respect to the class group of k.
A ZERO DENSITY ESTIMATE FOR THE SELBERG CLASS
Authors: MUKHOPADHYAY ANIRBAN , SRINIVAS KOTYADA
Published: June 2007

It is well known that bounds on moments of a specific L-function can lead to zero-density result for that L-function. In this paper, we generalize this argument to all L-functions in the Selberg class by assuming a certain second power moment. As an application, it is shown that in the case of symmetric-square L-function, this result improves the existing one.
EVALUATING CONVOLUTION SUMS OF THE DIVISOR FUNCTION BY QUASIMODULAR FORMS
Authors: ROYER EMMANUEL
Published: June 2007

We provide a systematic method to compute arithmetic sums including some previously computed by Alaca, Besge, Cheng, Glaisher, Huard, Lahiri, Lemire, Melfi, Ou, Ramanujan, Spearman and Williams. Our method is based on quasimodular forms. This extension of modular forms has been constructed by Kaneko and Zagier.
Incident Occurrence of Depressive Symptoms among Patients with Mild Cognitive Impairment – The Italian Longitudinal Study on Aging
Authors: Solfrizzi Vincenzo , D’Introno Alessia , Colacicco Anna M. , Capurso Cristiano , Del Parigi Angelo , Caselli Richard J. , Scapicchio Pier L. , Scafato Emanuele , Gandin Claudia , Capurso Antonio , Panza Francesco
Published: June 2007

Aims: We estimated the prevalence and incidence rates of depressive symptoms and the role of vascular risk factors and sociodemographic variables on the occurrence of depressive symptoms in mild cognitive impairment (MCI). Methods: In the Italian Longitudinal Study on Aging, 2,963 individuals from 5,632 65- to 84-year-old subjects were evaluated at the 1st and 2nd survey, with a 3.5-year follow-up. Dementia and MCI were classified using current criteria. Depressive symptoms were measured with the Geriatric Depression Scale. Results: Among the 2,963 participants, 139 prevalent MCI cases were diagnosed with a depressive symptoms prevalence rate of 63.3%. During the 3.5-year follow-up, we estimated an incidence rate of depressive symptoms of 29.6 per 100 person-years. No sociodemographic variables or vascular risk factors modified the incidence of depressive symptoms in cognitively stable MCI patients or in MCI patients who reverted to normal cognition. Conclusion: In our population, there was a high prevalence and incidence of depressive symptoms in MCI. Our findings do not provide support for a possible role of vascular risk factors in the development of depressive symptoms in MCI, although these findings were based on relatively few cases of MCI, limiting the capacity to draw definitive conclusions.
A SPECT Study of Apathy in Alzheimer’s Disease
Authors: Lanctôt Krista L. , Moosa Shehnaz , Herrmann Nathan , Leibovitch Farrell S. , Rothenburg Lana , Cotter Adolfo , Black Sandra E.
Published: June 2007

Background/Aims: To assess the association between regional cerebral blood flow (rCBF) and apathy in Alzheimer’s Disease (AD). Methods: SPECT and MRI scans were obtained from 51 nondepressed outpatients meeting criteria for probable AD (age 77.6 ± 6.6 years; MMSE 22.3 ± 5.1; 23 apathetic, 28 nonapathetic) and 23 healthy elderly (75.6 ± 3.8 years) controls. The following regions of interest (ROIs) were compared between apathetic and nonapathetic AD patients and then referenced against aged controls: anterior cingulate, orbitofrontal cortex, middle medial temporal cortex, hippocampus, medial superior temporal cortex, thalamus/hypothalamus and pons. Results: Apathetic and nonapathetic patients had significant differences in rCBF. Relative to nonapathetic AD patients, apathetic AD patients had lower perfusion in 2 ROIs (right orbitofrontal cortex and left anterior cingulate) and higher perfusion in 5 ROIs (right and left hippocampi, left medial superior temporal gyrus, and right and left middle medial temporal cortex). Comparison of rCBF in these 7 ROIs to healthy elderly controls confirmed hypoperfusion in the left anterior cingulate and right orbitofrontal cortex and suggested a relative sparing of perfusion among apathetic AD patients in the remaining 5 ROIs. Conclusions: In this group of nondepressed patients with AD, apathetic subjects displayed significant perfusion differences compared to nonapathetic subjects.
The Influence of Levodopa and the COMT Inhibitor on Serum Vitamin B12 and Folate Levels in Parkinson’s Disease Patients
Authors: Triantafyllou N.I. , Kararizou E. , Angelopoulos E. , Tsounis S. , Boufidou F. , Evangelopoulos M.E. , Nikolaou C. , Vassilopoulos D.
Published: June 2007

Serum folate and vitamin B12 levels were measured in 67 consecutive Parkinson’s disease patients treated either with levodopa + dopa decarboxylase inhibitor (DDC-i) plus catechol-O-methyltransferase inhibitors (COMT-i) or only with levodopa + DDC-i. The data were compared to 67 age-matched controls. Our findings show that levodopa-treated Parkinson’s disease patients have low folate (p < 0.0007) and vitamin B12 levels (p < 0.0003). They also demonstrate that the addition of a COMT-i to levodopa + DDC-i treatment causes lower serum vitamin B12 (p < 0.03) and folate levels (p < 0.005) than levodopa + DDC-i treatment alone. We suggest supplementary treatment with vitamin B12 and folic acid in these situations.
Electrophysiological Properties of Pituitary Cells in Primary Culture from Atlantic Cod (Gadus morhua)
Authors: Haug Trude M. , Hodne Kjetil , Weltzien Finn-Arne , Sand Olav
Published: June 2007

The aim of the present study was to explore the electrophysiological properties of pituitary cells from Atlantic cod (Gadus morhua), as a basis for future studies of the signaling pathways involved in the control of pituitary secretion in this species. Primary cultures of pituitary cells from maturing Atlantic cod were prepared by trypsin treatment and mechanical dispersion. Electrophysiological recordings were performed using the perforated patch clamp method. A subpopulation of large cells were selected for recordings. Spontaneous action potentials were observed in about 30% of the cells. The action potentials displayed a fast initial spike followed by a prolonged plateau. Correspondingly, the inward current elicited by depolarizing steps consisted of both a transient, tetrodotoxin-sensitive Na+ component and a nifedipine-sensitive Ca2+ component that was sustained when Ba2+ replaced Ca2+ as current carrier. The outward current was partially blocked both by 5 mM tetraethylammonium and 10 mM 4-aminopyridine. The voltage-activated ion channels present in these cells largely correspond to the ion channels of pituitary cells in other teleosts (goldfish, Carassius auratus, and tilapia, Oreochromis mossambicus) and mammals, although differences exist regarding the shape and duration of action potentials.
Inhibition of Apoptosis-Regulated Signaling Kinase-1 and Prevention of Congestive Heart Failure by Estrogen
Authors: Satoh Minoru , Matter Christian M. , Ogita Hisakazu , Takeshita Kyosuke , Wang Chao-Yung , Dorn Gerald W. , Liao James K.
Published: June 2007

Background—

Epidemiological studies have shown gender differences in the incidence of congestive heart failure (CHF); however, the role of estrogen in CHF is not known. We hypothesize that estrogen prevents cardiomyocyte apoptosis and the development of CHF.

Methods and Results—

17β-Estradiol (E2, 0.5 mg/60-day release) or placebo pellet was implanted subcutaneously into male Gαq transgenic (Gq) mice. After 8 weeks, E2 treatment decreased the extent of cardiac hypertrophy and dilation and improved contractility in Gq mice. E2 treatment also attenuated nicotinamide adenine dinucleotide phosphate oxidase activity and superoxide anion production via downregulation of Rac1. This correlated with reduced apoptosis in cardiomyocytes of Gq mice. The antioxidative properties of E2 were also associated with increased expression of thioredoxin (Trx), Trx reductases, and Trx reductase activity in the hearts of Gq mice. Furthermore, the activation of apoptosis signal-regulating kinase 1 and its downstream effectors, c-Jun N-terminal kinase and p38 mitogen-activated protein kinase, in the hearts of Gq mice was reduced by long-term E2 treatment. Indeed, E2 (10 nmol/L)-treated cardiomyocytes were much more resistant to angiotensin II–induced apoptosis. These antiapoptotic and cardioprotective effects of E2 were blocked by an estrogen receptor antagonist (ICI 182,780) and by a Trx reductase inhibitor (azelaic acid).

Conclusions—

These findings indicate that long-term E2 treatment improves CHF by antioxidative mechanisms that involve the upregulation of Trx and inhibition of Rac1-mediated attenuated nicotinamide adenine dinucleotide phosphate oxidase activity and apoptosis signal-regulating kinase 1 /c-Jun N-terminal kinase/p38 mitogen-activated protein kinase–mediated apoptosis. These results suggest that estrogen may be a useful adjunctive therapy for patients with CHF.
Coronary Artery Calcification Progression Is Heritable
Authors: Cassidy-Bushrow Andrea E. , Bielak Lawrence F. , Sheedy Patrick F. , Turner Stephen T. , Kullo Iftikhar J. , Lin Xihong , Peyser Patricia A.
Published: June 2007

Background—

Coronary artery calcification (CAC), a marker of coronary artery atherosclerosis, can be measured accurately and noninvasively with the use of electron beam computed tomography. Serial measures of CAC quantify progression of calcified coronary artery plaque. Little is known about the role of genetic factors in progression of CAC quantity.

Methods and Results—

We quantified the relative contributions of measured risk factors and unmeasured genes to CAC progression measured by 2 electron beam computed tomography examinations an average of 7.3 years apart in 877 asymptomatic white adults (46% men) from 625 families in a community-based sample. After adjustment for baseline risk factors and CAC quantity, the estimated heritability of CAC progression was 0.40 (
P
<0.001). Baseline risk factors and CAC quantity explained 64% of the variation in CAC progression. Thus, genetic factors explained 14% of the variation [(100−64)×(0.40)] in CAC progression. After adjustment for risk factors, the estimated genetic correlation (pleiotropy) between baseline CAC quantity and CAC progression was 0.80 and was significantly different than 0 (
P
<0.001) and 1 (
P
=0.037). The environmental correlation between baseline CAC quantity and CAC progression was 0.42 and was significantly different than 0 (
P
=0.006).

Conclusions—

Evidence was found that many but not all genetic factors influencing baseline CAC quantity also influence CAC progression. The identification of common and unique genetic influences on these traits will provide important insights into the genetic architecture of coronary artery atherosclerosis.
Long-Term Safety and Efficacy of Drug-Eluting Stents
Authors: Marzocchi Antonio , Saia Francesco , Piovaccari Giancarlo , Manari Antonio , Aurier Enrico , Benassi Alberto , Cremonesi Alberto , Percoco Gianfranco , Varani Elisabetta , Magnavacchi Paolo , Guastaroba Paolo , Grilli Roberto , Maresta Aleardo
Published: June 2007

Background—

The long-term safety and efficacy of drug-eluting stents (DES) have been questioned recently.

Methods and Results—

Between July 2002 and June 2005, 10 629 patients undergoing elective percutaneous coronary intervention with either DES (n=3064) or bare-metal stents (BMS, n=7565) were enrolled in a prospective registry comprising 13 hospitals. We assessed the cumulative incidence of major adverse cardiac events (death, acute myocardial infarction, and target-vessel revascularization) and angiographic stent thrombosis during 2-year follow-up. A propensity score analysis to adjust for different baseline clinical, angiographic, and procedural characteristics was performed. The 2-year unadjusted cumulative incidence of major adverse cardiac events was 17.8% in the DES group and 21.0% in the BMS group (
P
=0.003 by log-rank test). Angiographic stent thrombosis was 1.0% in the DES group and 0.6% in the BMS group (
P
=0.09). After adjustment, the 2-year cumulative incidence of death was 6.8% in the DES group and 7.4% in the BMS group (
P
=0.35), whereas the rates were 5.3% in DES and 5.8% in BMS for acute myocardial infarction (
P
=0.46), 9.1% in DES and 12.9% in BMS for target-vessel revascularization (
P
<0.00001), and 16.9% in DES and 21.8% in BMS for major adverse cardiac events (
P
<0.0001). Independent predictors of target-vessel revascularization in the DES group were diabetes mellitus (hazard ratio 1.36, 95% confidence interval 1.06 to 1.76), renal failure (hazard ratio 1.69, 95% confidence interval 1.06 to 2.69), and reference vessel diameter (hazard ratio 0.64, 95% confidence interval 0.45 to 0.93).

Conclusions—

In this large real-world population, the beneficial effect of DES in reducing the need for new revascularization compared with BMS extends to 2 years without evidence of a worse safety profile.
Cardiac Angiography in Renally Impaired Patients (CARE) Study
Authors: Solomon Richard J. , Natarajan Madhu K. , Doucet Serge , Sharma Samin K. , Staniloae Cezar S. , Katholi Richard E. , Gelormini Joseph L. , Labinaz Marino , Moreyra Abel E. ,   the Investigators of the CARE Study
Published: June 2007

Background—

No direct comparisons exist of the renal tolerability of the low-osmolality contrast medium iopamidol with that of the iso-osmolality contrast medium iodixanol in high-risk patients.

Methods and Results—

The present study is a multicenter, randomized, double-blind comparison of iopamidol and iodixanol in patients with chronic kidney disease (estimated glomerular filtration rate, 20 to 59 mL/min) who underwent cardiac angiography or percutaneous coronary interventions. Serum creatinine (SCr) levels and estimated glomerular filtration rate were assessed at baseline and 2 to 5 days after receiving medications. The primary outcome was a postdose SCr increase ≥0.5 mg/dL (44.2 μmol/L) over baseline. Secondary outcomes were a postdose SCr increase ≥25%, a postdose estimated glomerular filtration rate decrease of ≥25%, and the mean peak change in SCr. In 414 patients, contrast volume, presence of diabetes mellitus, use of N-acetylcysteine, mean baseline SCr, and estimated glomerular filtration rate were comparable in the 2 groups. SCr increases ≥0.5 mg/dL occurred in 4.4% (9 of 204 patients) after iopamidol and 6.7% (14 of 210 patients) after iodixanol (
P
=0.39), whereas rates of SCr increases ≥25% were 9.8% and 12.4%, respectively (
P
=0.44). In patients with diabetes, SCr increases ≥0.5 mg/dL were 5.1% (4 of 78 patients) with iopamidol and 13.0% (12 of 92 patients) with iodixanol (
P
=0.11), whereas SCr increases ≥25% were 10.3% and 15.2%, respectively (
P
=0.37). Mean post-SCr increases were significantly less with iopamidol (all patients: 0.07 versus 0.12 mg/dL, 6.2 versus 10.6 μmol/L,
P
=0.03; patients with diabetes: 0.07 versus 0.16 mg/dL, 6.2 versus 14.1 μmol/L,
P
=0.01).

Conclusions—

The rate of contrast-induced nephropathy, defined by multiple end points, is not statistically different after the intraarterial administration of iopamidol or iodixanol to high-risk patients, with or without diabetes mellitus. Any true difference between the agents is small and not likely to be clinically significant.
Sex Differences in Clinical Characteristics and Prognosis in a Broad Spectrum of Patients With Heart Failure
Authors: O’Meara Eileen , Clayton Tim , McEntegart Margaret B. , McMurray John J.V. , Piña Ileana L. , Granger Christopher B. , Östergren Jan , Michelson Eric L. , Solomon Scott D. , Pocock Stuart , Yusuf Salim , Swedberg Karl , Pfeffer Marc A.
Published: June 2007

Background—

We wished to test previous hypotheses that sex-related differences in mortality and morbidity may be due to differences in the cause of heart failure or in left ventricular ejection fraction (LVEF) by comparing fatal and nonfatal outcomes in women and men with heart failure and a broad spectrum of left ventricular ejection fraction.

Methods and Results—

We compared outcomes in 2400 women and 5199 men randomized in the Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity (CHARM) program using multivariable regression analyses. A total of 1188 women (50%) had a low LVEF (≤0.40), and 1212 had a preserved LVEF (>0.40). Among the men, 3388 (65%) had a low LVEF, and 1811 had a preserved LVEF. A total of 1216 women (51%) and 3465 men (67%) had an ischemic cause of their heart failure. All-cause mortality was 21.5% in women and 25.3% in men (adjusted hazard ratio [HR], 0.77; 95% CI, 0.69 to 0.86;
P
<0.001). Fewer women (30.4%) than men (33.3%) experienced cardiovascular death or heart failure hospitalization (adjusted HR, 0.83; 95% CI, 0.76 to 0.91;
P
<0.001). The risks of sudden death (HR, 0.70; 95% CI, 0.58 to 0.85) and death due to worsening heart failure (HR, 0.72; 95% CI, 0.58 to 0.89) were reduced to a comparable extent. The adjusted risk of cardiovascular hospitalization was also lower in women (HR, 0.88; 95% CI, 0.82 to 0.95), mainly because of a reduced risk of heart failure hospitalization (HR, 0.87; 95% CI, 0.78 to 0.97). Women had a lower risk of death irrespective of cause of heart failure or LVEF.

Conclusions—

Among patients with heart failure, women have lower risks of most fatal and nonfatal outcomes that are not explained, as previously suggested, by LVEF or origin of the heart failure.
Evaluation of Dose-Related Effects of Aspirin on Platelet Function
Authors: Gurbel Paul A. , Bliden Kevin P. , DiChiara Joseph , Newcomer Justin , Weng Willy , Neerchal Nagaraj K. , Gesheff Tania , Chaganti Srivasavi K. , Etherington Amena , Tantry Udaya S.
Published: June 2007

Background—

The antiplatelet effect of aspirin is attributed to platelet cyclooxygenase-1 inhibition. Controversy exists on the prevalence of platelet resistance to aspirin in patients with coronary artery disease and effects of aspirin dose on inhibition. Our primary aim was to determine the degree of platelet aspirin responsiveness in patients, as measured by commonly used methods, and to study the relation of aspirin dose to platelet inhibition.

Methods and Results—

We prospectively studied the effect of aspirin dosing on platelet function in 125 stable outpatients with coronary artery disease randomized in a double-blind, double-crossover investigation (81, 162, and 325 mg/d for 4 weeks each over a 12-week period). At all doses of aspirin, platelet function was low as indicated by arachidonic acid (AA)-induced light transmittance aggregation, thrombelastography, and VerifyNow. At any 1 dose, resistance to aspirin was 0% to 6% in the overall group when AA was used as the agonist, whereas it was 1% to 27% by other methods [collagen and ADP-induced light transmittance aggregation, platelet function analyzer (PFA-100)]. Platelet response to aspirin as measured by collagen-induced light transmittance aggregation, ADP-induced light transmittance aggregation, PFA-100 (81 mg versus 162 mg,
P
≤0.05), and urinary 11-dehydrothromboxane B
2
was dose-related (81 mg versus 325 mg,
P
=0.003). No carryover effects were observed.

Conclusions—

The assessment of aspirin resistance is highly assay-dependent; aspirin is an effective blocker of AA-induced platelet function at all doses, whereas higher estimates of resistance were observed with methods that do not use AA as the stimulus. The observation of dose-dependent effects despite nearly complete inhibition of AA-induced aggregation suggests that aspirin may exert antiplatelet properties through non–cyclooxygenase-1 pathways and deserves further investigation.
Emergency Department Physician Activation of the Catheterization Laboratory and Immediate Transfer to an Immediately Available Catheterization Laboratory Reduce Door-to-Balloon Time in ST-Elevation Myocardial Infarction
Authors: Khot Umesh N. , Johnson Michele L. , Ramsey Curtis , Khot Monica B. , Todd Randall , Shaikh Saeed R. , Berg William J.
Published: June 2007

Background—

Consensus guidelines and hospital quality-of-care programs recommend that ST-elevation myocardial infarction patients achieve a door-to-balloon time of ≤90 minutes. However, there are limited prospective data on specific measures to significantly reduce door-to-balloon time.

Methods and Results—

We prospectively determined the impact on median door-to-balloon time of a protocol mandating (1) emergency department physician activation of the catheterization laboratory and (2) immediate transfer of the patient to an immediately available catheterization laboratory by an in-house transfer team consisting of an emergency department nurse, a critical care unit nurse, and a chest pain unit nurse. We collected door-to-balloon time for 60 consecutive ST-elevation myocardial infarction patients undergoing emergency percutaneous intervention within 24 hours of presentation from October 1, 2004, through August 31, 2005, and compared this group with 86 consecutive ST-elevation myocardial infarction patients from September 1, 2005, through June 26, 2006, after protocol implementation. Median door-to-balloon time decreased overall (113.5 versus 75.5 minutes;
P
<0.0001), during regular hours (83.5 versus 64.5 minutes;
P
=0.005), during off-hours (123.5 versus 77.5 minutes;
P
<0.0001), and with transfer from an outside affiliated emergency department (147 versus 85 minutes;
P
=0.0006). Treatment within 90 minutes increased from 28% to 71% (
P
<0.0001). Mean infarct size decreased (peak creatinine kinase, 2623±3329 versus 1517±1556 IU/L;
P
=0.0089), as did hospital length of stay (5±7 versus 3±2 days;
P
=0.0097) and total hospital costs per admission ($26 826±29 497 versus $18 280±8943;
P
=0.0125).

Conclusions—

Emergency department physician activation of the catheterization laboratory and immediate transfer of the patient to an immediately available catheterization laboratory reduce door-to-balloon time, leading to a reduction in myocardial infarct size, hospital length of stay, and total hospital costs.
Intramyocardial Transplantation of Autologous CD34
+
Stem Cells for Intractable Angina
Authors: Losordo Douglas W. , Schatz Richard A. , White Christopher J. , Udelson James E. , Veereshwarayya Vimal , Durgin Michelle , Poh Kian Keong , Weinstein Robert , Kearney Marianne , Chaudhry Muqtada , Burg Aaron , Eaton Liz , Heyd Lindsay , Thorne Tina , Shturman Leon , Hoffmeister Peter , Story Ken , Zak Victor , Dowling Douglas , Traverse Jay H. , Olson Rachel E. , Flanagan Janice , Sodano Donata , Murayama Toshinori , Kawamoto Atsuhiko , Kusano Kengo Fukushima , Wollins Jill , Welt Frederick , Shah Pinak , Soukas Peter , Asahara Takayuki , Henry Timothy D.
Published: June 2007

Background—

A growing population of patients with coronary artery disease experiences angina that is not amenable to revascularization and is refractory to medical therapy. Preclinical studies have indicated that human CD34
+
stem cells induce neovascularization in ischemic myocardium, which enhances perfusion and function.

Methods and Results—

Twenty-four patients (19 men and 5 women aged 48 to 84 years) with Canadian Cardiovascular Society class 3 or 4 angina who were undergoing optimal medical treatment and who were not candidates for mechanical revascularization were enrolled in a double-blind, randomized (3:1), placebo-controlled dose-escalating study. Patients received granulocyte colony-stimulating factor 5 μg · kg
−1
· d
−1
for 5 days with leukapheresis on the fifth day. Selection of CD34
+
cells was performed with a Food and Drug Administration–approved device. Electromechanical mapping was performed to identify ischemic but viable regions of myocardium for injection of cells (versus saline). The total dose of cells was distributed in 10 intramyocardial, transendocardial injections. Patients were required to have an implantable cardioverter-defibrillator or to temporarily wear a LifeVest wearable defibrillator. No incidence was observed of myocardial infarction induced by mobilization or intramyocardial injection. The intramyocardial injection of cells or saline did not result in cardiac enzyme elevation, perforation, or pericardial effusion. No incidence of ventricular tachycardia or ventricular fibrillation occurred during the administration of granulocyte colony-stimulating factor or intramyocardial injections. One patient with a history of sudden cardiac death/ventricular tachycardia/ventricular fibrillation had catheter-induced ventricular tachycardia during mapping that required cardioversion. Serious adverse events were evenly distributed. Efficacy parameters including angina frequency, nitroglycerine usage, exercise time, and Canadian Cardiovascular Society class showed trends that favored CD34
+
cell–treated patients versus control subjects given placebo.

Conclusions—

A randomized trial of intramyocardial injection of autologous CD34
+
cells in patients with intractable angina was completed that provides evidence for feasibility, safety, and bioactivity. A larger phase IIb study is currently under way to further evaluate this therapy.
Small or Large Isolation Areas Around the Pulmonary Veins for the Treatment of Atrial Fibrillation?
Authors: Arentz Thomas , Weber Reinhold , Bürkle Gerd , Herrera Claudia , Blum Thomas , Stockinger Jochem , Minners Jan , Neumann Franz Josef , Kalusche Dietrich
Published: June 2007

Background—

Pulmonary vein (PV) isolation is a promising new treatment for atrial fibrillation (AF). We hypothesized that isolation of large areas around both ipsilateral PVs with verification of conduction block is more effective than the isolation of each individual PV.

Methods and Results—

A total of 110 patients, 67 with paroxysmal AF and 43 with persistent AF, were randomly assigned to undergo either isolation of each individual PV or isolation of large areas around both ipsilateral PVs. The isolation of each individual PV was an electrophysiologically guided, ostial segmental ablation with a 64-pole basket catheter or a 20-pole circular mapping catheter (group I). Isolation of large areas was performed around the 2 ipsilateral veins with a nonfluoroscopic navigation system and a circular 20-pole mapping catheter for verification of conduction block (group II). In both groups, an irrigated-tip ablation catheter (25 to 35 W) was used to achieve complete isolation. Procedure and ablation times were longer in group II, whereas fluoroscopic time was significantly shorter (
P
≤0.001). After a follow-up period of 15±4 months, 27 patients in group I (49%) and 37 patients in group II (67%) remained free of symptoms of AF and had no AF or atrial flutter during repetitive Holter monitoring without antiarrhythmic drug treatment after a single procedure (
P
≤0.05).

Conclusions—

The rate of success was significantly higher and fluoroscopy times were significantly lower in the group with large isolation areas around both ipsilateral PVs than in those who underwent individual PV isolation.
Both Estrogen Receptor Subtypes, α and β, Attenuate Cardiovascular Remodeling in Aldosterone Salt–Treated Rats
Authors: Arias-Loza Paula-Anahi , Hu Kai , Dienesch Charlotte , Mehlich Anna Maria , König Simone , Jazbutyte Virginia , Neyses Ludwig , Hegele-Hartung Christa , Heinrich Fritzemeier Karl , Pelzer Theo
Published: June 2007

Experimental and population-based studies indicate that female gender and estrogens protect the cardiovascular system against aldosterone-induced injury. Understanding the function of estrogens in heart disease requires more precise information on the role of both estrogen receptor (ER) subtypes, ERα and ERβ. Therefore, we determined whether selective activation of ERα or of ERβ would confer redundant, specific, or opposing effects on cardiovascular remodeling in aldosterone salt–treated rats. The ERα agonist 16α-LE2, the ERβ agonist 8β-VE2, and the nonselective estrogen receptor agonist 17β-estradiol lowered elevated blood pressure, cardiac mass, and cardiac myocyte cross-sectional areas, as well as increased perivascular collagen accumulation and vascular osteopontin expression in ovariectomized rats receiving chronic aldosterone infusion plus a high-salt diet for 8 weeks. Uterus atrophy was prevented by 16α-LE2 and 17β-estradiol but not by 8β-VE2. Cardiac proteome analyses by 2D gel electrophoresis, mass spectrometry, and peptide sequencing identified specific subsets of proteins involved in cardiac contractility, energy metabolism, cellular stress response and extracellular matrix formation that were regulated in opposite directions by aldosterone salt treatment and by different estrogen receptor agonists. We conclude that activation of either ERα or ERβ protects the cardiovascular system against the detrimental effects of aldosterone salt treatment and confers redundant, as well as specific, effects on cardiac protein expression. Nonfeminizing ERβ agonists such as 8β-VE2 have a therapeutic potential in the treatment of hypertensive heart disease.
Awake Systolic Blood Pressure Variability Correlates With Target-Organ Damage in Hypertensive Subjects
Authors: Tatasciore Alfonso , Renda Giulia , Zimarino Marco , Soccio Manola , Bilo Grzegorz , Parati Gianfranco , Schillaci Giuseppe , De Caterina Raffaele
Published: June 2007

Growing evidence associates blood pressure (BP) variability with cardiovascular events in hypertensive patients. Here we tested the existence of a relationship between awake BP variability and target-organ damage in subjects referred for suspected hypertension. Systolic and diastolic BP variability were assessed as the standard deviation of the mean out of 24-hour, awake and asleep BP recordings in 180 untreated subjects, referred for suspected hypertension. Measurements were done at 15-minute intervals during daytime and 30-minute intervals during nighttime. Left ventricular mass index (by echo), intima-media thickness (by carotid ultrasonography), and microalbuminuria were assessed as indices of cardiac, vascular and renal damage, respectively. Intima-media thickness and left ventricular mass index progressively increased across tertiles of awake systolic BP variability (
P
for trend=0.001 and 0.003, respectively). Conversely, microalbuminuria was similar in the 3 tertiles (
P
=NS). Multivariable analysis identified age (
P
=0.0001), awake systolic BP (
P
=0.001), awake systolic BP variability (
P
=0.015) and diastolic BP load (
P
=0.01) as independent predictors of intima-media thickness; age (
P
=0.0001), male sex (
P
=0.012), awake systolic (
P
=0.0001) and diastolic BP (
P
=0.035), and awake systolic BP variability (
P
=0.028) as independent predictors of left ventricular mass index; awake systolic BP variability (
P
=0.01) and diastolic BP load (
P
=0.01) as independent predictors of microalbuminuria. Therefore, awake systolic BP variability by non-invasive ambulatory BP monitoring correlates with sub-clinical target-organ damage, independent of mean BP levels. Such relationship, found in subjects referred for recently suspected hypertension, likely appears early in the natural history of hypertension.