bluuebunny/crossref_metadata_2025 huggingface dataset:
Volatile oils from leaves and stem barks of Cedrela ﬁssilis (Meliaceae): chemical composition and antibacterial activities
Authors: Lago João Henrique G. , de Ávila Paulo , de Aquino Elvis M. , Moreno Paulo Roberto H. , Ohara Mitsuko T. , Limberger Renata P. , Apel Mirian A. , Henriques Amélia T.
Published: May 2004

The volatile oils from the leaves and stem barks of Cedrela ﬁssilis were submitted to GC–MS analysis and separation by adsorption chromatography. The fractions were analysed by GC, 1H‐ and 13C‐NMR as well as GC–MS. The major components found in the leaf oil were β‐caryophyllene (26.3%) and bicyclogermacrene (34.6%), while in the stem bark oil the major compounds were β‐bisabolene (10.9%) and globulol (10.9%). In an antibacterial assay, only the leaf oil was able to inhibit growth of Staphylococcus aureus and Eschorichia coli. Copyright © 2004 John Wiley & Sons, Ltd.
Chemical composition of the oil and supercritical CO2 extract of Schinus molle L.
Authors: Marongiu Bruno , Porcedda Alessandra Piras Silvia , Casu Rita , Pierucci Paola
Published: May 2004

Supercritical carbon dioxide extraction allowed Schinus molle L. volatile oil to be obtained. Extraction conditions were as follows: pressure, 90 bar; temperature, 50 °C, carbon dioxide ﬂow, Φ = 1.0 kg/h. Waxes were entrapped in the ﬁrst separator set at 90 bar and ‐10 °C. The oil was recovered in the second separator, working at 15 bar and 10 °C. The main components were α‐phellandrene (26.5%), limonene + β‐phellandrene (21.0%), elemol (10.8%) and α‐eudesmol (6.1%). Comparison with the hydrodistilled oil (HD) did not reveal any large difference, whereas the signiﬁcant difference between the SFE and SD oils was the content of sesquiterpenes, which is higher in the SFE products. Collection of samples at different extraction times during supercritical extraction allowed changes of the oil composition to be monitored. Lighter compounds, as hydrocarbon monoterpenes, were extracted in shorter times than the heavier hydrocarbon and oxygenated sesquiterpenes. Copyright © 2004 John Wiley & Sons, Ltd.
Automatic unstructured surface mesh generation for complex configurations
Authors: Tremel Udo , Deister Frank , Hassan Oubay , Weatherill Nigel P.
Published: May 2004

In this paper a new object‐oriented (OO) approach is presented for automatic parallel advancing front based surface mesh generation and adaptive remeshing for complex configurations. Based on the ST++‐system the advantages of the OO design and implementation compared to the traditional structural approach are described. Algorithmic enhancements to the advancing front method are explained, enabling a robust NURBS based triangulation process directly on B‐rep CAD data. The message passing (MPI) parallelization strategy together with the achievable performance improvements are demonstrated. With the outlined parallel geometry analysis/rasterization a powerful method is described to derive automatically a well suited mesh size specification without any user‐interaction from scratch. The application of this method to a complex ‘real world’ example finishes this paper. Copyright © 2004 John Wiley & Sons, Ltd.
The haplotype runs test: The parent‐parent‐affected offspring trio design
Authors: Lange Ethan M. , Boehnke Michael
Published: May 2004

The increasing availability of maps of dense polymorphic markers makes use of haplotype data in family‐based association analyses an attractive alternative to single marker association tests. We describe a novel class of statistics designed to test for an association between marker haplotypes and a qualitative trait using the parent‐parent‐affected‐offspring trio design. Our haplotype runs test (HRT) is based on consecutive allele‐sharing between pairs of haplotypes. We assign weights according to the relative frequencies of the alleles for which the two haplotypes match. Herein, we compare the HRT to the maximum‐identity‐length‐contrast (MILC) statistic, the single‐locus transmission/disequilibrium test (TDT), and the generalized test of transmission disequilibrium for haplotype data, as implemented in the software TRANSMIT, using both simulated data and published haplotype data from the recessive disorder ataxia‐telangiectasia. Our simulation results suggest that the HRT outperforms the MILC and that the HRT provides comparable power to the TDT and TRANSMIT when the number of distinct founder haplotypes with a disease susceptibility allele is small but substantially outperforms the TDT and TRANSMIT when the number of distinct founder haplotypes with a disease susceptibility allele is even of modest size. © 2004 Wiley‐Liss, Inc.
The effect of MR scanner noise on auditory cortex activity using fMRI
Authors: Scarff Carrie J. , Dort Joseph C. , Eggermont Jos J. , Goodyear Bradley G.
Published: May 2004

Auditory functional magnetic resonance imaging (fMRI) studies are limited by the presence of noise produced by echo planar imaging (EPI). The current study quantifies the effect of MR scanner noise on psychophysical measures of the perception of loudness and on measures of tonotopy, the representation of auditory frequencies within the auditory cortex. Seven normal hearing adults were examined using tones of 5 different auditory frequencies (250, 500, 1,000, 2,000, 4,000 Hz) of equal loudness. Using an imaging protocol with peak MR scanner noise at 1,460 Hz, the perception of loudness and detectable fMRI activity in response to a 1‐kHz tone was less compared to other frequencies. When the imaging protocol was changed such that peak MR scanner noise occurred at 2,080 Hz, the perception of loudness and detectable fMRI activity in response to a 2‐kHz tone was less compared to other frequencies. The reduction in the measured fMRI activity for tones near scanner frequencies may be due to an inflated scanner‐induced baseline at those frequencies. In addition, fMRI activity decreased with increasing frequency, possibly due to the upward spread of masking of low‐frequency, high‐intensity tonal stimuli or the proximity of low‐frequency core and belt areas of the auditory cortex. These results demonstrate the direct effect of scanner noise and high‐intensity tonal stimuli on measurements of auditory cortex tonotopy. Hum. Brain Mapping 22:341–349, 2004. © 2004 Wiley‐Liss, Inc.
Medicines and the drug control treaties: is buprenorphine for opioid addiction at risk of being lost?
Authors: Costa e Silva J. A.
Published: May 2004

Over the past century, a worldwide system for the control of drugs with abuse potential has developed through the adoption of a series of international treaties. The important multilateral conventions currently in force are the United Nations Single Convention on Narcotic Drugs, 1961 (Single Convention), the United Nations Convention on Psychotropic Substances, 1971 (Psychotropic Convention) and the United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances, 1988. From the beginning, the aim of these drug control treaties has been to control the abuse and trafficking of substances with abuse potential while assuring that the availability of these drugs for medical and scientific purposes is not unduly restricted.

There is activity in the World Health Organization and the International Narcotics Control Board to determine whether the international control of buprenorphine, a partial mu‐opioid agonist used as an analgesic and for the treatment of opioid addiction, should be changed from the Psychotropic Convention to the Single Convention. This change would result in the classification and regulation of buprenorphine as a narcotic drug rather than a psychotropic substance. Such a move is unwarranted medically and scientifically and would provoke increased controls on buprenorphine that would fundamentally disrupt the medical practice of pain management and opioid replacement therapy around the world. The negative impact of inappropriate regulatory controls when licensed medicines come under such scrutiny are described. Copyright © 2004 John Wiley & Sons, Ltd.
Irrigation and fisheries: irreconcilable conflicts or potential synergies?
Authors: Nguyen‐Khoa S. , Smith L. E. D.
Published: May 2004

In situations of water scarcity, significant conflicts can arise between management of water for irrigation and inland fisheries. This paper considers the principles and lessons that can be drawn from the application of a conflict resolution mechanism—a protocol for participatory impact assessment and management—to a situation of conflict in the dry zone of Sri Lanka. Key features of this protocol are: (i) genuine participation of stakeholders; (ii) integrated assessment and management of impacts of irrigation on fisheries; (iii) management of information and an informed decision‐making process; and (iv) adoption of an iterative and learning approach. The two main sources of conflict between fishermen and irrigators in the case investigated arise in the management of reservoir water levels and in the disposal of drainage flows into coastal lagoons. Application of the protocol demonstrated ways to improve information and communication between parties, to reduce conflict and to improve resource management. Consensus for resource management options was found in emphasising the priority needs of the poorest sections of local communities, and in seeking means to improve management of irrigation to the benefit of both farmers and fishermen. Application of the protocol thus identified possible synergies between irrigation and fisheries where previously these activities had been viewed as purely antagonistic. Copyright © 2004 John Wiley & Sons, Ltd.
Impact of biological clogging agents on filter and emitter discharge characteristics of microirrigation systems
Authors: DehghaniSanij Hossein , Yamamoto Tahei , Rasiah Velu , Utsunomiya Jun , Inoue Mitsuhiro
Published: May 2004

Water application efficiency of microirrigation systems (MIS) may depend, at least partially, on algae and protozoa (biological clogging agents, BCAs) induced filter and emitter clogging. In this study we assessed the impact of BCA‐induced changes on water discharge rate and distribution uniformity from (i) emitters with different water flow cross‐section (CS) area, pressure compensation (PC) systems, and inbuilt filtration areas (FAs), and (ii) filters either made of urethane, sand, or disk in the Tohaku irrigation project in Japan. In a field experiment, four types of on‐line emitters on each of four laterals and four types of in‐line emitters on each of another four laterals were assessed for BCA‐induced emitter discharge performance without using filters in the field irrigation line. The emitters' discharge rate increased with increasing CS, FA, and working pressure (WP) and decreased when the emitters were on‐line in the laterals and with increasing BCA counts. Because BCAs are the only dynamic variable in the above relationship, we conclude that BCA‐induced clogging is a major issue when filters were not installed in field irrigation lines. The filter performance assessment based on the number of backwashings required to restore the working pressure to the recommended level indicated that BCA filtering by the sand filter was highest, followed by disk and urethane, respectively. Copyright © 2004 John Wiley & Sons, Ltd.
Basis set effects on calculated geometries: 6‐311++G** vs. aug‐cc‐pVDZ
Authors: Wiberg Kenneth B.
Published: May 2004

The effect of basis sets on MP2 and CCSD calculated geometries has been investigated for a series of small organic molecules with two to four nonhydrogen atoms. Whereas 6‐311++G** usually leads to satisfactory structures, this was not true with aug‐cc‐pVDZ, although it uses more basis functions than the former set. In addition, the smaller 6‐311++G** invariably leads to lower calculated energies than aug‐cc‐pVDZ. With a given basis set, CCSD gives more satisfactory calculated geometries than MP2, but with a much greater computation time. For the compounds in this report, B3LYP/6‐311++G** is quite effective in giving satisfactory calculated geometries at a relatively small computational cost. © 2004 Wiley Periodicals, Inc. J Comput Chem 25: 1342–1346, 2004
Electrostatic potentials and fields from density expansions of deformed atoms in molecules
Authors: Rico J. Fernández , López R. , Ema I. , Ramírez G.
Published: May 2004

The exact representation of the molecular density by means of atomic expansions, consisting in spherical harmonics times analytical radial factors, is employed for the calculation of electrostatic potentials, fields, and forces. The resulting procedure is equivalent to an atomic multipolar expansion in the long‐range regions, but works with similar efficiency and accuracy in the short‐range region, where multipolar expansions are not valid. The performances of this procedure are tested on the calculation of the electrostatic potential contour maps and electrostatic field flux lines of water and nitrobenzene, computed from high‐quality molecular electron densities obtained with Slater basis sets. © 2004 Wiley Periodicals, Inc. J Comput Chem 25: 1347–1354, 2004
Analytical method for the representation of atoms‐in‐molecules densities
Authors: Rico J. Fernández , López R. , Ramírez G. , Ema I. , Ludeña E. V.
Published: May 2004

We present analytic refinements and applications of the deformed atomic densities method [Fernández Rico, J.; López, R.; Ramírez, G. J Chem Phys 1999, 110, 4213–4220]. In this method the molecular electron density is partitioned into atomic contributions, using a minimal deformation criterion for every two‐center distributions, and the atomic contributions are expanded in spherical harmonics times radial factors. Recurrence relations are introduced for the partition of the two‐center distributions, and the final radial factors are expressed in terms of exponential functions multiplied by polynomials. Algorithms for the practical implementation are developed and tested, showing excellent performances. The usefulness of the present approach is illustrated by examining its ability to describe the deformation of atoms in different molecular environments and the relationship between these atomic densities and some chemical properties of molecules. © 2004 Wiley Periodicals, Inc. J Comput Chem 25: 1355–1363, 2004
Microtubule disassembly induces cytoskeletal remodeling and lung vascular barrier dysfunction: Role of Rho‐dependent mechanisms
Authors: Birukova Anna A. , Smurova Ksenya , Birukov Konstantin G. , Usatyuk Peter , Liu Feng , Kaibuchi Kozo , Ricks‐Cord Anila , Natarajan Viswanathan , Alieva Irina , Garcia Joe G.N. , Verin Alexander D.
Published: May 2004

Barrier dysfunction of pulmonary endothelial monolayer is associated with dramatic cytoskeletal reorganization, activation of actomyosin contractility, and gap formation. The linkage between the microtubule (MT) network and the contractile cytoskeleton has not been fully explored, however, clinical observations suggest that intravenous administration of anti‐cancer drugs and MT inhibitors (such as the vinca alkaloids) can lead to the sudden development of pulmonary edema in breast cancer patients. In this study, we investigated the crosstalk between MT and actomyosin cytoskeleton and characterized specific molecular mechanisms of endothelial cells (EC) barrier dysfunction induced by MT inhibitor nocodazole (ND). Our results demonstrate that MT disassembly by ND induced rapid decreases in transendothelial electrical resistance (TER) and actin cytoskeletal remodeling, indicating EC barrier dysfunction. These effects involved ND‐induced activation of Rho GTPase. Rho‐mediated activation of its downstream target, Rho‐kinase, induced phosphorylation of Rho‐kinase effector EC MLC phosphatase (MYPT1) at Thr696 and Thr850 resulting in MYPT1 inactivation. Phosphatase inhibition leaded to accumulation of diphospho‐MLC, which induced acto‐myosin polymerization, stress fiber formation and gap formation. Inhibition of Rho‐kinase by Y27632 abolished ND‐induced MYPT1 phosphorylation, MLC phosphorylation, and stress fiber formation. In addition, MT preservation via the MT stabilizer paclitaxel, Rho inhibition (via C3 exotoxin, or dominant negative (DN)‐Rho, or DN‐Rho‐kinase) attenuated ND‐induced TER decreases, stress fiber formation and MLC phosphorylation. Collectively, our results demonstrate a leading role for Rho‐dependent mechanisms in crosstalk between the MT and actomyosin cytoskeleton, and suggest Rho‐kinase and MYPT1 as major Rho effectors mediating pulmonary EC barrier disruption in response to ND‐induced MT disassembly. J. Cell. Physiol. 201: 55–70, 2004. © 2004 Wiley‐Liss, Inc.
Chromatin remodeling and stem cell theory of relativity
Authors: Cerny Jan , Quesenberry Peter J.
Published: May 2004

The field of stem cell biology is currently being redefined. Stem cell (hematopoietic and non‐hematopoietic) differentiation has been considered hierarchical in nature, but recent data suggest that there is no progenitor/stem cell hierarchy, but rather a reversible continuum. The stem cell (hematopoietic and non‐hematopoietic) phenotype, the total differentiation capacity (hematopoietic and non‐hematopoietic), gene expression as well as other stem cell functional characteristics (homing, receptor and adhesion molecule expression) vary throughout a cell‐cycle transit widely. This seems to be dependent on shifting chromatin and gene expression with cell‐cycle transit. The published data on DNA methylation, histone acetylation, and also RNAi, the major regulators of gene expression, conjoins very well and provides an explanation for the major issues of stem cell biology. Those features of stem cells mentioned above can be rather difficult to apprehend when a classical hierarchy biology view is applied, but they become clear and easier to understand once they are correlated with the underlining epigenetic changes. We are entering a new era of stem cell biology the era of “chromatinomics.” We are one step closer to the practical use of cellular therapy for degenerative diseases. J. Cell. Physiol. 201: 1–16, 2004. © 2004 Wiley‐Liss, Inc.
Chloride channels in the small intestinal cell line IEC‐18
Authors: Basavappa Srisaila , Vulapalli Sreesatya Raju , Zhang Hui , Yule David , Coon Steven , Sundaram Uma
Published: May 2004

Small intestinal crypt cells play a critical role in modulating Cl− secretion during digestion. The types of Cl− channels mediating Cl− secretion in the small intestine was investigated using the intestinal epithelial cell line, IEC‐18, which was derived from rat small intestine crypt cells. In initial radioisotope efflux studies, exposure to forskolin, ionomycin or a decrease in extracellular osmolarity significantly increased 36Cl efflux as compared to control cells. Whole cell patch clamp techniques were subsequently used to examine in more detail the swelling‐, Ca2+‐, and cAMP‐activated Cl− conductance. Decreasing the extracellular osmolarity from 290 to 200 mOsm activated a large outwardly rectifying Cl− current that was voltage‐independent and had an anion selectivity of I− > Cl−. Increasing cytosolic Ca2+ by ionomycin activated whole cell Cl− currents, which were also outwardly rectifying but were voltage‐dependent. The increase in intracellular Ca2+ levels with ionomycin was confirmed with fura‐2 loaded IEC‐18 cells. A third type of whole cell Cl− current was observed after increases in intracellular cAMP induced by forskolin. These cAMP‐activated Cl− currents have properties consistent with cystic fibrosis transmembrane regulator (CFTR) Cl− channels, as the currents were blocked by glibenclamide or NPPB but insensitive to DIDS. In addition, the current–voltage relationship was linear and had an anion selectivity of Cl− > I−. Confocal immunofluorescence studies and Western blots with two different anti‐CFTR antibodies confirmed the expression of CFTR. These results suggest that small intestinal crypt cells express multiple types of Cl− channels, which may all contribute to net Cl− secretion. © 2005 Wiley‐Liss, Inc.
Mouse HFE inhibits Tf‐uptake and iron accumulation but induces non‐transferrin bound iron (NTBI)‐uptake in transformed mouse fibroblasts
Authors: Kielmanowicz Merav Gleit , Laham Nihay , Coligan John E. , Lemonnier François , Ehrlich Rachel
Published: May 2004

Iron‐uptake and storage are tightly regulated to guarantee sufficient iron for essential cellular processes and to prevent the production of damaging free radicals. A non‐classical class I MHC molecule, the hemochromatosis factor (HFE), has been shown to regulate iron metabolism, potentially via its interaction with the transferrin receptor. Whereas, the effect of human HFE (hHFE) on transferrin/transferrin receptor association, as well as on transferrin receptor recycling and the level of cellular iron pools in various cell lines was analyzed, very little is known about the mouse HFE (mHFE) protein. In the following study, our aim was to analyze in more detail the function of mHFE. Surprisingly, we observed that over‐expression of mHFE, but not of hHFE, in a mouse transformed cell line, results in a most significant inhibition of transferrin‐uptake which correlated with apoptotic cell death. mHFE inhibited transferrin‐uptake immediately following transfection and this inhibition persisted in the surviving stable transfectants. Concomitantly, cellular iron derived from transferrin‐iron uptake was dramatically limited. The activation of a non‐transferrin bound iron‐uptake pathway that functions in the stable mHFE‐transfected clones could explain their normal growth curves and survival. The hypothesis that iron starvation can induce iron‐uptake by a novel transferrin‐independent pathway is discussed. © 2005 Wiley‐Liss, Inc.
Analysis of myocardial perfusion MRI
Authors: Jerosch‐Herold Michael , Seethamraju Ravi Teja , Swingen Cory M. , Wilke Norbert M. , Stillman Arthur E.
Published: May 2004

Rapid MR imaging (MRI) during the first pass of an injected tracer is used to assess myocardial perfusion with a spatial resolution of 2–3 mm, and to detect any regional impairments of myocardial blood flow (MBF) that may lead to ischemia. The spatial resolution is sufficient to detect flow reductions that are limited to the subendocardial layer. The capacity of the coronary system to increase MBF severalfold in response to vasodilation can be quantified by analysis of the myocardial contrast enhancement. The myocardial perfusion reserve (MPR) is a useful concept for quantifying the vasodilator response. The perfusion reserve can be estimated from the ratio of MBFs during vasodilation and at baseline, in units identical to those used for invasive measurements with labeled microspheres, or from dimensionless flow indices normalized by their value for autoregulated flow at rest. The perfusion reserve can be reduced as a result of a blunted hyperemic response and/or an abnormal resting blood flow. The absolute quantification of MBF removes uncertainties in the evaluation of the vasodilator response, and can be achieved without the use of complex tracer kinetic models; therefore, its application to clinical studies is feasible. J. Magn. Reson. Imaging 2004;19:758–770. © 2004 Wiley‐Liss, Inc.
Imaging of coronary calcification by computed tomography
Authors: Thompson Brad H. , Stanford William
Published: May 2004

As an unequivocal biomarker for arteriosclerosis, the presence of coronary calcium serves as a qualitative reflection of the severity of coronary artery disease (CAD). Greater calcium burdens correlate with more advanced disease, a higher likelihood of coronary stenoses, and a higher risk for coronary heart disease (CHD). Empirically, the quantification of coronary calcium not only provides an accurate reflection of disease severity, but also has great potential as a screening tool for CHD. Computed tomography (CT) has been shown to be capable of providing accurate, noninvasive measurements of coronary calcification. Evidence shows that calcium measurements by CT correlate well with histological plaque analyses, and that calcium burdens accurately reflect disease severity and can be used to assess individual risk for CHD. The purpose of this review article is to examine the accumulated evidence that has attempted to validate CT as a diagnostic tool for CAD and as a screening exam for CHD. J. Magn. Reson. Imaging 2004;19:720–733. © 2004 Wiley‐Liss, Inc.
MR and CT assessment for ischemic cardiac disease
Authors: White Richard D.
Published: May 2004

Magnetic resonance imaging and/or contrast‐enhanced multidetector computed tomography may be used separately or, often more effectively, in an integrated fashion, to address important issues in patients with coronary artery disease causing ischemic cardiac disease (ICD). These issues include complications of myocardial infarction, such as ventricular dysfunction, myocardial wall rupture, aneurysm formation, intracavitary thrombus, mitral insufficiency, and pericarditis, as well as aspects of planning and monitoring therapy for ICD, such as revascularization and ventricular aneurysm repair. J. Magn. Reson. Imaging 2004;19:659–675. © 2004 Wiley‐Liss, Inc.
MRI of atherosclerosis
Authors: Yuan Chun , Kerwin William S.
Published: May 2004

The emergence of high‐resolution, rapid imaging methods has enabled MRI to noninvasively image the fine internal structure of atherosclerotic artery walls. This capability has, in turn, captured the interest of clinicians, who see it as an opportunity to assess disease severity based on the characteristics of atherosclerotic lesions themselves, rather than only their effects on the vessel lumen. MRI of atherosclerosis thus has the potential to be used in medical treatment decisions or to assess the effects of experimental treatment options. Given this potential, a number of research groups have been investigating MRI of atherosclerosis in an effort to establish the ability of MRI to determine atherosclerotic plaque burden, detect plaque composition, and ultimately identify vulnerable plaque before it leads to a clinical event. In this review, the current state of the art is summarized for the three primary vessel targets: the carotid artery, the aorta, and the coronary arteries. J. Magn. Reson. Imaging 2004;19:710–719. © 2004 Wiley‐Liss, Inc.
Magnetic resonance imaging–guided coronary interventions
Authors: Tsekos Nikolaos V. , Atalar Ergin , Li Debiao , Omary Reed A. , Serfaty Jean‐Michel , Woodard Pamela K.
Published: May 2004

Magnetic resonance imaging (MRI) guidance for coronary interventions offers potential advantages over conventional x‐ray angiography. Advantages include the use of nonionizing radiation, combined assessment of anatomy and function, and three‐dimensional assessment of the coronary arteries leading to the myocardium. These advantages have prompted a series of recent studies in this field. Real‐time coronary MR angiography, with low‐dose catheter‐directed intraarterial (IA) infusion of contrast media, has achieved in‐plane spatial resolution as low as 0.8 × 0.8 mm2 and temporal resolution as short as 130 msec per image. Catheter‐based IA injection of contrast agent has proven useful in the collection of multislice and three‐dimensional images, not only for coronary intervention guidance, but also in the assessment of regional myocardial perfusion fed by the affected vessel. Actively visible guidewires and guiding catheters, based on the loopless antenna concept, have been effectively used to negotiate tortuous coronary vessels during catheterization, permitting placement of coronary angioplasty balloon catheters. Passive tracking approaches have been used to image contrast agent–filled coronary catheters and to place susceptibility‐based endovascular stents. Although the field is in its infancy, these early results demonstrate the feasibility for performing MRI‐guided coronary interventions. Although further methodological and technical developments are required before these methods become clinically applicable, we anticipate that MRI someday will be included in the armamentarium of techniques used to diagnose and treat coronary artery disease. J. Magn. Reson. Imaging 2004;19:734–749. © 2004 Wiley‐Liss, Inc.
Imaging of myocardial perfusion with magnetic resonance
Authors: Barkhausen Jörg , Hunold Peter , Jochims Markus , Debatin Jörg F.
Published: May 2004

Coronary artery disease (CAD) is currently the leading cause of death in developed nations. Reflecting the complexity of cardiac function and morphology, noninvasive diagnosis of CAD represents a major challenge for medical imaging. Although coronary artery stenoses can be depicted with magnetic resonance (MR) and computed tomography (CT) techniques, its functional or hemodynamic impact frequently remains elusive. Therefore, there is growing interest in other, target organ‐specific parameters such as myocardial function at stress and first‐pass myocardial perfusion imaging to assess myocardial blood flow. This review explores the pathophysiologic background, recent technical developments, and current clinical status of first‐pass MR imaging (MRI) of myocardial perfusion. J. Magn. Reson. Imaging 2004;19:750–757. © 2004 Wiley‐Liss, Inc.
Coronary artery magnetic resonance angiography
Authors: Flamm Scott D. , Muthupillai Raja
Published: May 2004

Coronary magnetic resonance angiography (coronary MRA) continues to advance rapidly from both a technical and clinical perspective. Coronary MRA has benefited directly from improvements in spatial resolution, contrast definition, and advances in motion correction, which have furthered its routine use in evaluating coronary artery bypass grafts and anomalous coronary arteries. Work in refining the techniques for more accurate identification of coronary artery disease (CAD) continues, with advances in navigator‐gated and breath‐hold motion correction techniques, novel k‐space strategies (e.g., spiral and radial k‐space filling), development and application of intravascular contrast agents, and imaging at higher field strengths. Ultimately, these developments may lead to the routine application of coronary MRA as a screening tool for CAD. This article reviews the development of coronary MRA, discusses the requirements and tools necessary for optimal visualization of the coronary arteries, and describes the application of coronary MRA to acquired and congenital CAD. J. Magn. Reson. Imaging 2004;19:686–709. © 2004 Wiley‐Liss, Inc.
Magnetic resonance imaging for the assessment of myocardial viability
Authors: Thomson Louise E.J. , Kim Raymond J. , Judd Robert M.
Published: May 2004

The identification of myocardial viability in the setting of left ventricular (LV) dysfunction is crucial for the prediction of functional recovery following revascularization. Although echocardiography, positron emission tomography (PET), and nuclear imaging have validated roles, recent advances in cardiac magnetic resonance (CMR) technology and availability have led to increased experience in CMR for identification of myocardial viability. CMR has unique advantages in the ability of magnetic resonance spectroscopy (MRS) to measure subcellular components of myocardium, and in the image resolution of magnetic resonance proton imaging. As a result of excellent image resolution and advances in pulse sequences and coil technology, magnetic resonance imaging (MRI) can be used to identify the transmural extent of myocardial infarction (MI) in vivo for the first time. This review of the role of CMR in myocardial viability imaging describes the acute and chronic settings of ventricular dysfunction and concepts regarding the underlying pathophysiology. Recent advances in MRS and MRI are discussed, including the potential for dobutamine MRI to identify viable myocardium and a detailed review of the technique of delayed gadolinium (Gd) contrast hyperenhancement for visualization of viable and nonviable myocardium. J. Magn. Reson. Imaging 2004;18:771–788. © 2004 Wiley‐Liss, Inc.
Assessment of pericardial disease by magnetic resonance and computed tomography
Authors: Axel Leon
Published: May 2004

Pericardial disease and its consequences can be well shown with magnetic resonance imaging (MRI) and computed tomography (CT). Here I review the normal and pathologic anatomy and physiology of the pericardium, approaches to MRI and CT imaging of the pericardium, and some specific considerations in common conditions affecting the pericardium. J. Magn. Reson. Imaging 2004;19:816–826. © 2004 Wiley‐Liss, Inc.
Magnetic resonance and computed tomographic evaluation of congenital heart disease
Authors: Boxt Lawrence M.
Published: May 2004

Magnetic resonance imaging (MRI) and contrast‐enhanced computed tomography (CT) provide noninvasive visualization of morphologic changes in pediatric and adult patients with congenital heart disease, as well as the functional changes caused by the underlying morphologic abnormalities. Clinical experience with MRI is richer than that with fast CT, but CT appears to provide accurate and high‐quality imagery for diagnosis. The two modalities may be complementary. That is, intracardiac anatomy is so well depicted by MRI, and CT provides exquisite images of the great vessels. Furthermore, in adult patients, MR and CT are helpful in demonstrating and quantitating physiologic changes superimposed by acquired cardiovascular disease on the underlying congenital malformations. Using MRI, spin echo acquisitions provide the image data for evaluation of morphologic changes, and gradient reversal techniques add functional and flow data to complement morphologic changes. Contrast‐enhanced electrocardiographic (ECG)‐gated multidetector and electron beam CT examination provide morphologic information and may be used as a data set for off‐line functional quantitation. J. Magn. Reson. Imaging 2004;19:827–847. © 2004 Wiley‐Liss, Inc.
Magnetic resonance and computed tomography imaging of arrhythmogenic right ventricular dysplasia
Authors: Tandri Harikrishna , Bomma Chandra , Calkins Hugh , Bluemke David A.
Published: May 2004

Arrhythmogenic right ventricular dysplasia (ARVD) is a familial cardiomyopathy that causes fibro‐fatty replacement of the right ventricle (RV), leading to sudden death due to ventricular arrhythmias. The disease is an important cause of sudden death in individuals younger than 35 years of age. Structural and functional abnormalities of the RV constitute an important diagnostic criterion for the disease. Diagnosis of ARVD is often a challenge as conventional imaging modalities have significant limitations to visualize the RV. Recently, magnetic resonance imaging (MRI) and computed tomographic (CT) imaging have emerged as robust clinical tools for evaluation of myocardial pathology. In addition to providing morphologic and functional information, both imaging modalities have the ability to demonstrate intramyocardial fat, which is the pathological hallmark in ARVD. This article discusses the current status and role of MRI and CT imaging in the diagnosis of ARVD. J. Magn. Reson. Imaging 2004;19:848–858. © 2004 Wiley‐Liss, Inc.
MR imaging assessment of cardiac function
Authors: Pujadas Sandra , Reddy Gautham P. , Weber Oliver , Lee Jennifer J. , Higgins Charles B.
Published: May 2004

Magnetic resonance (MR) imaging is an accurate and reproducible technique for assessment of ventricular function. Although echocardiography is the mainstay for evaluation of cardiac function, dobutamine stress MR imaging has been shown to be as safe as echocardiography for patients with coronary artery disease and more accurate in patients with suboptimal echocardiographic image quality. This article reviews MR imaging techniques, methods of pharmacologic stress, and clinical applications for assessment of cardiac function, primarily left ventricular function. J. Magn. Reson. Imaging 2004;19:789–799. © 2004 Wiley‐Liss, Inc.
Isolation and molecular identification of echovirus 13 isolated from patients of aseptic meningitis in Korea, 2002
Authors: Cheon Doo‐Sung , Lee Jiwon , Lee Kangbum , Lee Sunhwa , Park Kwisung , Ahn Jungbae , Jee Youngmee , Yoon Jaedeuk , Cho Haewol
Published: May 2004

During 2002, several epidemics of aseptic meningitis were attributed to echovirus 13 in Korea. The causative agents of these outbreaks were isolated and identified using rhabdosarcoma cells, HEp‐2 and Buffalo green monkey kidney cells, and a neutralization test using monospecific antiserum. Fifty‐four echovirus 13 isolates were isolated from patients with aseptic meningitis in the provinces, Seoul, Kyonggi, Gwangju, Jeonju, Busan, and Ulsan. Symptoms associated with aseptic meningitis infection in patients included the occurrence of headaches and mild fever. Molecular characterization of echovirus 13 samples was achieved by sequence and phylogenetic analyses on partial VP1 sequences from 20 Korean isolates and 10 foreign isolates listed in Genbank. Minor variation was observed among the Korean isolates, which formed a unique cluster with isolates of German and Japanese origin. The marked similarities between isolates could be attributed to a relatively recent arrival of the virus in Korea. This is the first such investigation of aseptic meningitis caused by echovirus 13 on the Korean peninsula. J. Med. Virol. 73:439–442, 2004. © 2004 Wiley‐Liss, Inc.
SARS coronavirus induces apoptosis in Vero E6 Cells
Authors: Yan Huimin , Xiao Gengfu , Zhang Jiamin , Hu Yuanyang , Yuan Fang , Cole David K. , Zheng Congyi , Gao George F.
Published: May 2004

Severe acute respiratory syndrome (SARS) is an emerging infectious disease. Its etiological agent has been convincingly identified as a new member of family Coronaviridae (SARS‐CoV). It causes serious damage to the respiratory system yet the mechanism is not clear. Infection‐induced apoptosis or necrosis is suspected but no direct evidence for this yet exists. To date, Vero E6 cells are the only cell line that could be used to replicate the virus with obvious CPE (cytopathic effect) in vitro. It is known for some viruses (including members of family Coronaviridae) that CPE can be caused either by virus‐induced apoptosis (active death) or cell necrosis (passive death). In this study, we examined the apoptosis in the SARS‐CoV infected Vero E6 cells. Indeed, the results do show that the CPE was induced by apoptosis rather than necrosis, shown by typical DNA fragmentation, through the existence of apoptotic bodies and swollen mitochondria. This observation has some implications for the SARS‐CoV pathogenicity: SARS‐CoV does induce apoptosis in cell cultures and might have the same effect in vivo, responsible for the severe damage of the respiratory system. J. Med. Virol. 73:323–331, 2004. © 2004 Wiley‐Liss, Inc.
The life cycle of SARS coronavirus in Vero E6 cells
Authors: Qinfen Zhang , Jinming Cui , Xiaojun Huang , Huanying Zheng , Jicheng Huang , Ling Fang , Kunpeng Li , Jingqiang Zhang
Published: May 2004

The aim of the study was to establish the life cycle of severe acute respiratory syndrome‐associated coronavirus (SARS CoV) in host cells and determine the pathogenesis of SARS. Vero E6 cells (African green monkey kidney cells) were inoculated with SARS coronavirus for 3, 7, 24, 48, and 72 hr, respectively, and were observed under electron microscope. It was found that the SARS coronavirus entered the cells through membrane fusion instead of endocytosis, and then the nucleocapsids assembled in the RER and matured by budding into the smooth vesicles, which were derived from the Golgi apparatus. The smooth vesicles fused with the cell membrane, and the mature particles were released. A special phenomenon was that some virus‐like particles appeared in the nucleus. We propose a scheme of the life cycle of SARS coronavirus and discuss the mechanism of its replication in Vero E6 cells. J. Med. Virol. 73:332–337, 2004. © 2004 Wiley‐Liss, Inc.
Evaluation of antibody responses against SARS coronaviral nucleocapsid or spike proteins by immunoblotting or ELISA
Authors: Huang Li‐Rung , Chiu Chi‐Ming , Yeh Shiou‐Hwei , Huang Wen‐Hung , Hsueh Po‐Ren , Yang Wen‐Zieh , Yang Jyh‐Yuan , Su Ih‐Jen , Chang Shan‐Chwen , Chen Pei‐Jer
Published: May 2004

Severe acute respiratory syndrome (SARS)‐CoV is a newly emerging virus that causes SARS with high mortality rate in infected people. To study the humoral responses against SARS‐CoV, we evaluated nucleocapsid (N) and spike (S) proteins‐specific antibodies in patients' sera by Western blotting and enzyme‐linked immunosorbent assay (ELISA). Recombinant N and S proteins of SARS‐CoV were purified from transformed E. coli. Serum specimens from 40 SARS‐CoV‐infected patients in the convalescent phase were analyzed by Western blotting using the purified antigens. Serial serum specimens from 12 RT‐PCR‐confirmed SARS patients were assayed by ELISA using the recombinant N protein as coated antigen. By Western blotting, 97.5% of the SARS patients were positive for N protein‐specific antibodies whereas only 47.5% of the samples were positive for S protein‐specific antibodies. Using N protein‐based ELISA, 10 out of the 12 patients were positive for N protein‐specific antibodies and 6 of them showed seroconversion at mean of 16 days after onset of fever. Immunoblotting was useful for detecting the humoral immune response after SARS‐CoV infection. Antibodies against SARS‐CoV N protein appear at the early stage of infection, therefore, N protein‐based ELISA could serve as a simple, sensitive, and specific test for diagnosing SARS‐CoV infection. J. Med. Virol. 73:338–346, 2004. © 2004 Wiley‐Liss, Inc.
Failure and success of HIV tests for the prevention of HIV‐1 transmission by blood and tissue donations
Authors: Najioullah Fatiha , Barlet Valérie , Renaudier Philippe , Guitton Cathy , Crova Philippe , Guérin Jean‐Claude , Peyramond Dominique , Trabaud Marie‐Anne , Coudurier Nicole , Tardy Jean‐Claude , André Patrice
Published: May 2004

French blood banks recently implemented nucleic acid testing (NAT) of all blood donations to reduce the risk of HIV transmission during the pre‐seroconversion period. For tissue donation, HIV infection screening relies on HIV p24 antigen and anti‐HIV1 and 2 antibody detection. In this report, two related cases of infectious donations are described from a cornea donor during the preseroconversion window who was infected by an HIV antibody and NAT negative blood donor. After investigation, the blood donor was found to be herself in the preseroconversion window. Two months after donation, she was found to be HIV positive. The residual risk of HIV infectious blood donations since NAT has been introduced is estimated to be lower than one out of 2.5 millions. Individual NAT instead of minipool testing would not increase significantly the blood transfusion safety. In contrast, introduction of NAT should be considered to increase tissue donation safety as soon as such screening will be possible technically. J. Med. Virol. 73:347–349, 2004. © 2004 Wiley‐Liss, Inc.
Long‐term suppression of plasma viremia with highly active antiretroviral therapy despite virus evolution and very limited selection of drug‐resistant genotypes
Authors: Pariente Nonia , Pernas María , Rosa Rafael de la , Gómez‐Mariano Gema , Fernández Guerau , Rubio Amalia , López Mariola , Benito José Miguel , López‐Galíndez Cecilio , Leal Manuel , Domingo Esteban , Martinez Miguel Angel , Mas Antonio
Published: May 2004

HIV‐1 evolution and the possible emergence of mutations associated with resistance to antiretroviral inhibitors have been evaluated in a cohort of sixty‐three patients successfully treated with highly active antiretroviral therapy (HAART). The patients under effective HAART were recruited in three different hospitals in Spain, and none of them had been treated (naïve) before entering this study. HIV‐1 RNA levels, CD4+, and CD8+ T‐cell counts were determined, and nucleotide sequences of proviral regions encoding protease and reverse transcriptase (RT) were obtained for longitudinal blood samples spanning a mean follow‐up period of 88 weeks. Phylogenetic reconstructions and calculations of genetic distances among the different sequences of each patient were performed. All except one of the patients under study showed an early and sustained decrease in plasma HIV‐1 RNA to levels that were below 200 copies/ml. The plasma viral decline paralleled a significant increase in the CD4+ T‐lymphocyte counts. Amino acid sequence analyses revealed the occurrence of mutations associated with antiretroviral resistance in nine patients (14.3%) during HAART treatment, that in some cases could be attributed to excess G to A transitions. In six of the nine patients, the mutations conferred resistance to inhibitors administered in the treatment regime, although the mutations did not result in treatment failure. Sequence comparisons revealed viral evolution during the period of treatment in 47.5% of the patients. The results indicate successful suppression of HIV‐1 under HAART for extended time periods, indistinguishable for patients in which evidence of virus evolution could or could not be documented. J. Med. Virol. 73:350–361, 2004. © 2004 Wiley‐Liss, Inc.
Downregulation of CXCR5 in CD27− B cells of HIV‐1 infected patients
Authors: Chong Yong , Nabeshima Shigeki , Furusyo Norihiro , Murata Masayuki , Yamaji Kouzaburo , Hayashi Jun
Published: May 2004

The CD27− (naive) B cells of HIV‐1 infected patients have been shown to be increased in frequency and to be activated, as indicated by high CD38 expression on the cell surface. CXCR5, a B cell chemokine receptor, is expressed on circulating CD27− (naive) B cells and plays a pivotal role in peripheral B cell development. To investigate the effect of HIV‐1 infection on the expression of this chemokine receptor on naive B cells, the expression level of CXCR5 on CD27− B cells was examined in 19 drug‐naive HIV‐1 infected patients, 27 HAART‐treated patients, and 20 controls. CXCR5 expression on CD27− B cells was significantly lower in drug‐naive patients than in HAART‐treated patients and controls (P < 0.01). CD27− B cells with high CD38 expression exhibited low CXCR5 expression. The CXCR5 expression level on CD27− B cells recovered to within the normal range after effective antiretroviral therapy. These findings suggested that HIV‐1 infection induces a remarkable phenotypic alteration of naive B cells and that the activated naive B cells found in HIV‐1 infection downregulate CXCR5 on their surface. Impaired homing of naive B cells may contribute to HIV‐1 induced immunological deficiencies. J. Med. Virol. 73:362–367, 2004. © 2004 Wiley‐Liss, Inc.
Genetic analysis of hepatitis A virus isolates from Brazil
Authors: de Paula Vanessa S. , Lu Ling , Niel Christian , Gaspar Ana M.C. , Robertson Betty H.
Published: May 2004

A limited number of hepatitis A virus (HAV) isolates from South America have been characterised at the genomic level. IgM anti‐HAV positive serum samples collected from patients with hepatitis A living in the five geographical regions of Brazil (North, Northeast, Central, South, and Southeast) were used to obtain HAV isolates and determine their genetic relatedness. Of the 232 case isolates, sequence data were obtained from the VP1/2A junction region of the HAV genome. All isolates were classified in genotype I; 231 belonged to subgenotype IA, and one to subgenotype IB. HAV isolates from four States formed distinct clusters of highly related sequences. However, isolates from other states did not cluster and the sequences from those states were intermingled with sequences found in the other states. The amino acid sequences of all but two isolates showed a Leu → Ile substitution at position 42 in the 2A protein. This substitution appeared to be a characteristic geographic fingerprint of HAV sequences within Brazil. J. Med. Virol. 73:378–383, 2004. © 2004 Wiley‐Liss, Inc.