bluuebunny/crossref_metadata_2025_split huggingface dataset:
Serial, noninvasive, in vivo magnetic resonance microscopy detects the development of atherosclerosis in apolipoprotein E‐deficient mice and its progression by arterial wall remodeling
Authors: Choudhury Robin P. , Fayad Zahi A. , Aguinaldo J. Gilberto , Itskovich Vitalii V. , Rong James X. , Fallon John T. , Fisher Edward A. 
Published: January 2003

AbstractPurposeTo test the ability of serial, in vivo magnetic resonance microscopy (MRM) to detect the development of atherosclerosis and quantify its progression in apolipoprotein E‐deficient mice.Materials and MethodsThe abdominal aortae of six ApoE−/− and three wild‐type (WT) control mice were imaged by MRM at 9.4T. Proton density weighted images were obtained (TR = 2000, TE = 9 msec) using four signal averages. The image resolution was 109 × 109 × 500 μm3. The six ApoE−/− mice underwent serial MRM three to five times over a period ≤ 44 weeks. Multiple, anatomically aligned MRM slices (N = 6–11 per time point, total 202) were compared serially in each animal.ResultsThe abdominal aorta remained free of atherosclerosis until 20 weeks of age but thereafter, atherosclerosis was identified in all ApoE−/− mice (P < 0.05 to P < 0.001), but no WT controls. Lesion progression was accompanied by positive remodeling in which atherosclerosis within the aortic wall was accommodated by an increase in total cross sectional area (P < 0.01), while lumen area was unchanged.ConclusionSerial MRM demonstrated the development and progression of atherosclerosis in mouse aorta. Importantly, progression of atherosclerosis could be identified within individual animals. By following the same aortic lesions over time, MRM demonstrated that progression of atherosclerosis in mice is associated with positive arterial remodeling. J. Magn. Reson. Imaging 2003;17:184–189. © 2003 Wiley‐Liss, Inc.
MR imaging of the thyroid: Correlation between apparent diffusion coefficient and thyroid gland scintigraphy
Authors: Tezuka Mikio , Murata Yuji , Ishida Ryuji , Ohashi Isamu , Hirata Yukio , Shibuya Hitoshi 
Published: January 2003

AbstractPurposeTo evaluate the usefulness of echo‐planar MR imaging for assessing the thyroid function and confirm the clinical use of MR imaging for thyroid diseases.Materials and MethodsThirty‐four patients with a variety of thyroid disorders (24 Graves disease; five subacute thyroiditis; five Hashimoto thyroiditis) were examined using T1‐, T2‐, and diffusion‐weighted magnetic resonance (MR) imaging and thyroid scintigraphy with Tc‐99m pertechnetate.ResultsThe ADC values obtained from the diffusion‐weighted images of the patients with Graves disease were significantly higher than those of patients with subacute hyroiditis and Hashimoto thyroiditis, though no difference among those disorders was observed on T1‐ and T2‐weighted images. Based on the ADC value, anisotropy was not observed in the thyroid gland. An ADC value of 1.82 × 10−3 mm2/second or higher indicated the presence of Graves disease (sensitivity 75%, specificity 80%).ConclusionDiffusion‐weighted MR images may be of value for the diagnosis of thyroid diseases and could be clinically important in the evaluation of thyroid function. J. Magn. Reson. Imaging 2003;17:163–169. © 2003 Wiley‐Liss, Inc.
MRI of the liver: Can true FISP replace HASTE?
Authors: Herborn Christoph U. , Vogt Florian , Lauenstein Thomas C. , Goyen Mathias , Debatin Jörg F. , Ruehm Stephan G. 
Published: January 2003

AbstractPurposeTo determine the diagnostic accuracy of two fast breath‐hold magnetic resonance (MR) imaging sequences, half‐Fourier acquired single turbo spin‐echo (HASTE) and true fast imaging with steady state precession (TrueFISP), for the detection and characterization of focal liver lesionsMaterials and MethodsA total of 186 patients with suspected focal liver lesions were enrolled in this study. All patients underwent the same standardized study protocol including HASTE and TrueFISP. A consensus reading based on all available image data served as a standard of reference for classifying lesions into cysts, hemangiomas, focal nodular hyperplasia, or malignant/other lesions. All malignant lesions, as well as hepatic adenomas and abscesses, were histologically verified. Each separated by an eight‐week interval, HASTE and TrueFISP images were retrospectively reviewed in random order for the detection and characterization of focal hepatic lesions. Finally, a receiver operating characteristic (ROC) analysis was calculated.ResultsHASTE images had an overall sensitivity of 0.86 and a specificity of 0.91, whereas TrueFISP showed an overall sensitivity and specificity of 0.79 and 0.83, respectively (p>0.1).ConclusionNeither HASTE nor TrueFISP alone are sufficient for the detection and characterization of hepatic lesions. J. Magn. Reson. Imaging 2003;17:190–196. © 2003 Wiley‐Liss, Inc.
Percutaneous MR‐guided discography in a low‐field system using optical instrument tracking: A feasibility study
Authors: Sequeiros Roberto Blanco , Klemola Rauli , Ojala Risto , Jyrkinen Lasse , Vaara Teuvo , Tervonen Osmo 
Published: January 2003

AbstractPurposeTo evaluate the feasibility of MRI‐guided discography with optical tracking.Material and Methods12 consecutive patients who had a clinical suspicion of lumbar discogenic pain and/or suggestive finding of disc degeneration in imaging studies (MRI, CT, plain radiography) underwent MRI‐guided discography in order to determine possible pain provocation during puncture and contrast injection. An 0.23 T open configuration MRI device with interventional tools (Outlook Proview, Philips Medical Systems, MR Technologies, Finland) was used in procedural imaging and instrument guidance. An optical guidance tool was attached to the MRI compatible needle (Chiba‐type MReye, Cook, Bloomington, IN). After initial disc puncture, 1–2 mL of gadolinium contrast (Magnevist, 469 mg/mL, Schering AG, Germany) saline mixture (1:8) was injected into the disc. Immediately after injection, sagittal FE T1 weighted images were obtained to verify the final position of the needle and formation of the MRI discogram. On nine patients, additional noncontrast sagittal fast spin echo (FSE) T1, FSE T2, and axial 3D T1 gradient echo imaging was performed before and after contrast media injection to obtain MRI discograms.ResultsOverall, 35 disc punctures were initialized and 34 MRI discograms were obtained. In all punctures, a positive or negative pain response was obtained. The average time for performing a procedure for three discs was 1 hour 25 minutes (minimum 45 minutes, maximum 2 hours, 15 minutes), and the average number of imaging sequences used for a puncturing one disc was 12. On one disc, the puncture failed and a discogram was not acquired. There was one complication (disc collapse) reported during follow‐up.Conclusion: Our results show that MRI guidance in performing discography is accurate and relatively safe. It is a technically comparable method to CT‐guidance or fluoroscopy. J. Magn. Reson. Imaging 2003;17:214–219. © 2003 Wiley‐Liss, Inc.
Coronary MR angiography: Respiratory motion correction with BACSPIN
Authors: Hardy Christopher J. , Zhao Lei , Zong Xuli , Saranathan Manojkumar , Yucel E. Kent 
Published: January 2003

AbstractPurposeTo improve the signal‐to‐noise ratio (SNR) of breath‐held coronary magnetic resonance angiography (CMRA) without increasing the number or duration of breath holds.Materials and MethodsIn this BACSPIN (Breathing AutoCorrection with SPiral INterleaves) technique, a single breath‐held electrocardiogram (ECG)‐gated multi‐slice interleaved‐spiral data set is acquired, followed by repeated imaging of the same slices during free breathing. Each spiral interleaf from the breath‐held data set is used as a standard for comparison with corresponding acquisitions at the same interleaf angle during free breathing. The most closely matched acquisitions are incorporated into a multi‐slice, multi‐average data set with increasing SNR over time. In‐plane translations of the coronary artery can be measured and compensated for each accepted acquisition before combination with the other acquisitions.ResultsCMRA was performed on six volunteers, with improved SNR and minimal motional blurring. In some cases, breath holding could be dispensed with completely and the average respiratory position used as a reference.ConclusionBACSPIN provides a promising method for CMRA with improved SNR and limited breath‐holding requirements. J. Magn. Reson. Imaging 2003;17:170–176. © 2003 Wiley‐Liss, Inc.
Efficacy of passive acoustic screening: Implications for the design of imager and MR‐suite
Authors: Moelker Adriaan , Vogel Mika W. , Pattynama Peter M. T. 
Published: January 2003

AbstractPurposeTo investigate the efficacy of passive acoustic screening in the magnetic resonance (MR) environment by reducing direct and indirect MR‐related acoustic noise, both from the patient's and health worker's perspective.Materials and MethodsDirect acoustic noise refers to sound originating from the inner and outer shrouds of the MR imager, and indirect noise to acoustic reflections from the walls of the MR suite. Sound measurements were obtained inside the magnet bore (patient position) and at the entrance of the MR imager (health worker position). Inner and outer shrouds and walls were lined with thick layers of sound insulation to eliminate the direct and indirect acoustic pathways. Sound pressure levels (SPLs) and octave band frequencies were acquired during various MR imaging sequences at 1.5 T.ResultsInside the magnet bore, direct acoustic noise radiating from the inner shroud was most relevant, with substantial reductions of up to 18.8 dB when using passive screening of the magnetic bore. At the magnet bore entrance, blocking acoustic noise from the outer shroud and reflections showed significant reductions of 4.5 and 2.8 dB, respectively, and 9.4 dB when simultaneously applied. Inner shroud coverage contributed minimally to the overall SPL reduction.ConclusionMaximum noise reduction by passive acoustic screening can be achieved by reducing direct sound conduction through the inner and outer shrouds. Additional measures to optimize the acoustic properties of the MR suite have only little effect. J. Magn. Reson. Imaging 2003;17:270–275. © 2003 Wiley‐Liss, Inc.
In vivo and in vitro MR spectroscopic profile of central neurocytomas
Authors: Jayasundar Rama , Shah Tariq , Vaishya Sandeep , Singh Virender P. , Sarkar Chitra 
Published: January 2003

AbstractThis study reports in vivo and in vitro magnetic resonance spectroscopic findings in two cases of central neurocytomas (CNC) confirmed by immunohistochemistry. Volume localized in vivo proton magnetic resonance spectroscopy (MRS) was carried out before surgery using a point resolved spectroscopy (PRESS) sequence with a repetition time of six seconds and an echo time of 135 msec. Normal spectrum was obtained from gray matter from a volunteer for comparison. 1H and 31P in vitro MRS studies were carried out at 9.4 T on the extracts prepared from the surgically excised tumors. The in vivo spectra showed prominent glycine (Gly) and choline (Cho) and low N‐acetyl aspartate compared to the normal. The Gly peak was assigned using the in vitro studies. These studies showed that the major contribution to the Cho peak observed in vivo is from phosphocholine. A combination of the presence of NAA and an increased Gly in the proton MR spectrum could be a characteristic feature of CNCs, which are rare intraventricular tumors of neuronal origin. J. Magn. Reson. Imaging 2003;17:256–260. © 2003 Wiley‐Liss, Inc.
Precise 3D skeletal kinematics using fast phase contrast magnetic resonance imaging
Authors: Rebmann Andrea J. , Sheehan Frances T. 
Published: January 2003

AbstractPurposeTo examine the precision of cine‐phase contrast (PC) magnetic resonance imaging (MRI) techniques as applied to the quantification of three‐dimensional knee joint kinematics.Materials and MethodsThe knee joints of eight healthy volunteers were studied using three different dynamic, PC MRI protocols: cine‐PC (one average), cine‐PC (two averages), and cine‐PC with segmented phase encoding (fast‐PC).ResultsFast‐PC has comparable precision, shorter scan times, and improved subject interexam variability (SIEV) compared to cine‐PC (two averages). Further, cine‐PC (one average) has low precision and high SIEV, making fast‐PC the preferred method of data acquisition. Specifically, the precision of fast‐PC MRI in measuring knee joint kinematics ranged from 0.22°–1.16°.ConclusionA cine‐PC MRI technique utilizing segmented phase encoding (fast‐PC MRI) acquires dynamic data at a faster rate than other PC imaging protocols, without compromising data precision. Being able to acquire precise 3D kinematics with shorter imaging times is critical if we are to use this technique to advance ongoing research in musculoskeletal kinematics. J. Magn. Reson. Imaging 2003;17:206–213. © 2003 Wiley‐Liss, Inc.
Uptake of glutamate is impaired in the cortical penumbra of the rat following middle cerebral artery occlusion: An in vivo microdialysis extraction study
Authors: Bruhn Torben , Christensen Thomas , Diemer Nils Henrik 
Published: January 2003

AbstractBy using microdialysis extraction of 3H‐D‐aspartate and concomitant recordings of extracellular direct current (DC) potentials, the effect of middle cerebral artery occlusion (MCAO) was studied continuously over a period of 100 min in the cerebral cortex of rats. From analysis of the DC potentials, rats subjected to MCAO could be divided into three groups, one in which the dialysis probe was located in the ischemic core, one in which the probe was in the penumbra, and one in which the probe was in nonischemic tissue. In general, extraction of 3H‐D‐aspartate was positively correlated with the DC potential; i.e., changes in the extraction were concurrent with changes in the DC potential. Comparing the different animal groups by integration of all extraction values obtained during MCAO over time, 3H‐D‐aspartate extraction was reduced by 40% in the penumbra, and by 58% in the ischemic core, compared with the sham‐operated controls. No changes was found in the nonischemic group. In the penumbra group, extraction of 3H‐D‐aspartate was reduced initially upon institution of MCAO but recovered to control‐like levels over a period of 15–40 min, despite ongoing MCAO. In addition, extraction was reduced transiently during periinfarct depolarizations. A mean of all extraction values obtained during MCAO in the penumbra group was reduced by 47% compared with a mean of values obtained before institution of MCAO. Induction of death resulted in a reduction of 3H‐D‐aspartate extraction by 86%. The present results provide direct evidence that uptake of Glu is reduced both in the ischemic core and in the penumbra of the cerebral cortex following MCAO in rats, possibly contributing to the initiation and spread of infarction. The results further indicate that uptake of Glu in the penumbra recovers to control‐like levels, despite ongoing MCAO, providing evidence that Glu uptake by the Glu transporter proteins is reinstituted and/or up‐regulated. © 2002 Wiley‐Liss, Inc.
Inhibition of long‐term potentiation by interleukin‐8: Implications for human immunodeficiency virus‐1‐associated dementia
Authors: Xiong Huangui , Boyle Jeffery , Winkelbauer Matthew , Gorantla Santhi , Zheng Jialin , Ghorpade Anuja , Persidsky Yuri , Carlson Kimberly A. , Gendelman Howard E. 
Published: January 2003

AbstractHuman immunodeficiency virus type 1 (HIV‐1)‐infected mononuclear phagocytes (MP; brain macrophages and microglia) secrete a number of toxic factors that affect the pathogenesis of HIV‐1‐associated dementia (HAD). The identification and relative role of each MP toxin for neuronal dysfunction during HAD are not well understood. Interleukin‐8 (IL‐8), a CXC chemokine involved in leukocyte activation and chemotaxis, is constitutively produced by MP, and elevated levels of IL‐8 mRNA were detected in the brains of patients with HIV‐1 encephalitis (HIVE) by both ribonuclease protection assays and real‐time PCR. To determine the role that IL‐8 might play in the neuronal dysfunction in HAD, we studied its effect on synaptic transmission and plasticity in the CA1 region of hippocampus, the seat of learning and memory. Bath application of IL‐8 (50 ng/ml) to rat hippocampal slices had no effect on basal synaptic transmission. However, IL‐8 was shown to inhibit long‐term potentiation (LTP) in a concentration‐dependent manner. In control and IL‐8‐treated slices, the LTP magnitudes were 167.8% ± 11.9% (mean ± SE; n = 17) and 122.2% ± 16.2% of basal levels (n = 13), respectively. These differences were statistically significant (P < 0.05). Preincubation of hippocampal slices with a monoclonal CXCR2 antibody (2 μg/ml) but not control IgG (2 μg/ml) blocked IL‐8‐induced inhibition of LTP. The expression of CXCR2 receptors in the CA1 region was shown by Western blot assays. The induction of IL‐8 in HAD, its inhibition of LTP, and the expression of its receptor, CXCR2, in the hippocampus all suggest that it plays a role in the cognitive dysfunction associated with HAD. © 2002 Wiley‐Liss, Inc.
Opposite effects of α1‐ and β‐adrenoceptor stimulation on both glutamate‐ and γ‐aminobutyric acid‐mediated spontaneous transmission in cultured rat hippocampal neurons
Authors: Croce Ariane , Astier Hélène , Récasens Max , Vignes Michel 
Published: January 2003

AbstractThe effects of adrenergic receptor stimulation on spontaneous synaptic transmission were investigated in cultured rat hippocampal neurons by recording spontaneous excitatory and inhibitory postsynaptic currents (sEPSC and sIPSC). Noradrenaline (NA) inhibited sEPSC in a concentration‐dependent manner, with maximal effect at 10 μM. The α1‐ and α2‐adrenoceptor‐selective agonists cirazoline and clonidine induced an inhibition of sEPSC appearance, whereas the β‐adrenoceptor agonist isoproterenol elicited an increase. The inhibitory effect of NA was reversed by α1‐adrenoceptor blockade. The participation of γ‐aminobutyric acid (GABA)B‐receptor stimulation in the inhibitory effect of NA was further examined. GABAB‐receptor stimulation with baclofen induced a strong inhibition of bursting activity, which was fully reversed by the GABAB antagonist CGP 55845. By itself, CGP 55845 exerted a stimulatory effect on sEPSC frequency. In the presence of CGP 55845, the inhibitory effects of cirazoline and clonidine were maintained. NA (1, 10, and 100 μM) and α‐adrenoceptor agonists decreased miniature EPSC and IPSC occurrence, whereas β‐adrenergic stimulation increased it. In 50% of the cells examined, NA (1, 10 μM) had a stimulatory effect on sIPSC, whereas, in the remaining 50% of cells, NA (1, 10 μM) had an inhibitory effect. In all the cells, 100 μM NA induced an inhibition of sIPSC. The inhibitory effect of NA was due to α1‐receptor stimulation, whereas the excitatory effect was due to β‐receptor stimulation. In cultured hippocampal neurons, spontaneous excitatory and inhibitory synaptic transmissions are both similarly altered by adrenoceptor stimulation. However, in a subset of cells, low concentrations of NA mediate an increase of sIPSC via β‐adrenoceptor activation. © 2002 Wiley‐Liss, Inc.
Representing identities through tourism: encounters of ethnic minorities in Dali, Yunnan Province, People's Republic of China
Authors: Doorne S. , Ateljevic I. , Bai Z. 
Published: January 2003

AbstractIn the current era of globalisation ȧand regional economic integration, localised concerns with cultural identity, historical memory and collective belonging are assuming a new significance. Rather than signalling the end of localised identities, however, the current period has infused processes of identity formation with elements of political economy. One central component of political economy through which these processes are being expressed is tourism. In this context, as the social sciences have begun to take tourism seriously when addressing broader issues of culture and society, this paper elaborates on new arenas through which processes of identity formation are being articulated.
Drawing on a current research project focused on cultural tourism in Dali, Yunnan Province, China, the discussion emphasises the extent to which cultural identities are appropriated, constructed and traded through and around material objects of touristic exchange. Copyright © 2003 John Wiley & Sons, Ltd.
Services and functions provided by European city tourist offices: a longitudinal study
Authors: Wöber Karl W. , Hwang Yeong‐Hyeon , Fesenmaier Daniel R. 
Published: January 2003

AbstractTourism has become a major source of employment, revenue, international awareness and opportunity in European cities. As competition among European cities grows, the efficiency of management in city tourism organisations (CTOs) becomes increasingly important. This article reports on a longitudinal study of 50 European CTOs over the 4‐year period from 1995 to 1999. The aim of the study is to examine the changes in functions provided by European CTOs during the given period of time. Findings reveal that five identifiable function categories can characterise the changes that happened during the given period of time: hotel booking service, commerce, conventional information dissemination, advanced information product and relationship management. It is argued that information technology and role change are the main driving forces of these changes. Copyright © 2003 John Wiley & Sons, Ltd.
A comparison of training activities in the Austrian and German accommodation trade using the TrainingActivityDegree
Authors: Langer G. 
Published: January 2003

AbstractThis article introduces the TrainingActivityDegree (TAD), a new method for the quantitative measurement of training activities, by presenting the empirical results from a practical application in which the training activities in the Austrian and German accommodation trade were compared. In the accommodation trade survey, a clear need for a method for acquiring reliable data of training activities in a fragmented branch such as the accommodation trade arose. Consequently the TAD index was developed. The practical application within an exploratory survey demonstrates its suitability for acquiring and comparing training participation, not only in the Austrian and German accommodation trade. Copyright © 2003 John Wiley & Sons, Ltd.
Testing a cultural tourism typology
Authors: McKercher Bob , du Cros Hilary 
Published: January 2003

AbstractThis paper tests further a cultural tourism typology based on the interface between centrality of cultural tourism as a trip motive and the depth of experience. Five types of cultural tourist are identified that represent five benefit‐based segments. The segments are tested against a variety of trip, demographic, motivational, preferred activity, awareness, cultural distance and activity variables. Significant differences are noted between the groups, suggesting that the model presented may be effective in segmenting the cultural tourism market. Moreover, although the segmentation process is predicated on two variables, these variables are reflective of underlying trip motivation, activity preference and cultural distance factors noted between the different types of cultural tourist. Copyright © 2003 John Wiley & Sons, Ltd.