bluuebunny/crossref_metadata_2025_split huggingface dataset:
Feasibility of using real‐time MRI to measure joint kinematics in 1.5T and open‐bore 0.5T systems
Authors: Draper Christine E. , Santos Juan M. , Kourtis Lampros C. , Besier Thor F. , Fredericson Michael , Beaupre Gary S. , Gold Garry E. , Delp Scott L. 
Published: June 2008

AbstractPurposeTo test the feasibility and accuracy of measuring joint motion with real‐time MRI in a 1.5T scanner and in a 0.5T open‐bore scanner and to assess the dependence of measurement accuracy on movement speed.Materials and MethodsWe developed an MRI‐compatible motion phantom to evaluate the accuracy of tracking bone positions with real‐time MRI for varying movement speeds. The measurement error was determined by comparing phantom positions estimated from real‐time MRI to those measured using optical motion capture techniques. To assess the feasibility of measuring in vivo joint motion, we calculated 2D knee joint kinematics during knee extension in six subjects and compared them to previously reported measurements.ResultsMeasurement accuracy decreased as the phantom's movement speed increased. The measurement accuracy was within 2 mm for velocities up to 217 mm/s in the 1.5T scanner and 38 mm/s in the 0.5T scanner. We measured knee joint kinematics with small intraobserver variation (variance of 0.8° for rotation and 3.6% of patellar width for translation).ConclusionOur results suggest that real‐time MRI can be used to measure joint kinematics when 2 mm accuracy is sufficient. They can also be used to prescribe the speed of joint motion necessary to achieve certain measurement accuracy. J. Magn. Reson. Imaging 2008;28:158–166. © 2008 Wiley‐Liss, Inc.
Cartilage imaging at 3.0T with gradient refocused acquisition in the steady‐state (GRASS) and IDEAL fat‐water separation
Authors: Kijowski Richard , Tuite Michael , Passov Leo , Shimakawa Ann , Hu Huanzhou , Reeder Scott B. 
Published: June 2008

AbstractPurposeTo demonstrate the feasibility of evaluating the articular cartilage of the knee joint at 3.0T using gradient refocused acquisition in the steady‐state (GRASS) and iterative decomposition of water and fat with echo asymmetry and least‐squares estimation (IDEAL) fat‐water separation.Materials and MethodsBloch equation simulations and a clinical pilot study (n = 10 knees) were performed to determine the influence of flip angle of the IDEAL‐GRASS sequence on the signal‐to‐noise ratio (SNR) of cartilage and synovial fluid and the contrast‐to‐noise ratio (CNR) between cartilage and synovial fluid at 3.0T. The optimized IDEAL‐GRASS sequence was then performed on 30 symptomatic patients as part of the routine 3.0T knee MRI examination at our institution.ResultsThe optimal flip angle was 50° for IDEAL‐GRASS cartilage imaging, which maximized contrast between cartilage and synovial fluid. The IDEAL‐GRASS sequence consistently produced high‐quality fat‐ and water‐separated images of the knee with bright synovial fluid and 0.39 × 0.67 × 1.0 mm resolution in 5 minutes. IDEAL‐GRASS images had high cartilage SNR and high contrast between cartilage and adjacent joint structures. The IDEAL‐GRASS sequence provided excellent visualization of cartilage lesions in all patients.ConclusionThe IDEAL‐GRASS sequence shows promise for use as a morphologic cartilage imaging sequence at 3.0T. J. Magn. Reson. Imaging 2008;28:167–174. © 2008 Wiley‐Liss, Inc.
3D nongadolinium‐enhanced ECG‐gated MRA of the distal lower extremities: Preliminary clinical experience
Authors: Lim Ruth P. , Hecht Elizabeth M. , Xu Jian , Babb James S. , Oesingmann Niels , Wong Samson , Muhs Bart E. , Gagne Paul , Lee Vivian S. 
Published: June 2008

AbstractPurposeTo report our initial experience implementing a noncontrast‐enhanced electrocardiograph (ECG) gated fast spin echo magnetic resonance angiography (MRA) technique for assessment of the calf arteries.Materials and MethodsNoncontrast MRA images of 36 clinical patients examined over a 6‐month period were evaluated by two radiologists for length and degree of stenosis of arterial segments. Diagnostic confidence in the technique was also recorded. The reference standard was a consensus reading by both radiologists using the noncontrast technique combined with two gadolinium‐enhanced techniques: bolus‐chase and time‐resolved imaging.ResultsFor stenosis evaluation the noncontrast technique demonstrated accuracy 79.4% (1083/1364), sensitivity 85.4% (437/512), and specificity 75.8% (646/852). The sequence demonstrated high negative predictive value (92.3%, 646/700). The technique had serious artifacts leading to poor diagnostic confidence in 17 patients (47.2%). These included motion (n = 7) and artifacts specific to the sequence, including inaccurate trigger delays (n = 5), linear artifact (n = 7), and vessel blurring (n = 5). When only patients in whom there was satisfactory diagnostic confidence were considered, accuracy, sensitivity, and negative predictive value were 92.2% (661/717), 92.4% (158/171), and 97.5% (503/516), respectively.ConclusionOur results indicate that when technically successful, noncontrast‐enhanced MRA using ECG‐gated fast spin echo can provide accurate imaging of the calf and pedal arteries. However, further development and optimization are needed to improve the robustness of the technique. J. Magn. Reson. Imaging 2008;28:181–189. © 2008 Wiley‐Liss, Inc.
Change in knee cartilage T2 in response to mechanical loading
Authors: Nishii Takashi , Kuroda Kagayaki , Matsuoka Yuichiro , Sahara Tomohiro , Yoshikawa Hideki 
Published: June 2008

AbstractPurposeTo assess the clinical feasibility of magnetic resonance (MR) imaging with a mechanical loading system for evaluation of load‐bearing function in knee joints using cartilage T2 as a surrogate of cartilage matrix changes.Materials and MethodsSagittal T2 maps of the medial and lateral femorotibial joints of 22 healthy volunteers were obtained using 3.0T MR imaging. After preloading for 6–9 minutes, MR images under static loading conditions were obtained by applying axial compression force of 50% of body weight during imaging. T2 values of the femoral and tibial cartilage at the weight‐bearing area were compared between unloading and loading conditions.ResultsUnder loading conditions, mean cartilage T2 decreased, depending on location of the knee cartilage. For the femoral side a significant decrease in T2 with loading was observed only at the region in direct contact with the opposing tibial cartilage, in the medial femoral cartilage (5.4%, P < 0.0005). For the tibial side a significant decrease in T2 with loading was widely observed in the medial and lateral joint, at regions both covered and not covered by the meniscus (4.3%–7.6%, P < 0.005).ConclusionMR imaging with mechanical loading is feasible to detect site‐specific changes in cartilage T2 during static loading. J. Magn. Reson. Imaging 2008;28:175–180. © 2008 Wiley‐Liss, Inc.
Investigation and validation of intersite fMRI studies using the same imaging hardware
Authors: Sutton Bradley P. , Goh Joshua , Hebrank Andrew , Welsh Robert C. , Chee Michael W.L. , Park Denise C. 
Published: June 2008

AbstractPurposeTo provide a between‐site comparison of functional MRI (fMRI) signal reproducibility in two laboratories equipped with identical imaging hardware and software. Many studies have looked at within‐subject reliability and more recent efforts have begun to calibrate responses across sites, magnetic field strengths, and software. By comparing identical imaging hardware and software, we provide a benchmark for future multisite comparisons.Materials and MethodsWe evaluated system compatibility based on noise and stability properties of phantom scans and contrast estimates from repeated runs of a blocked motor and visual task on the same four subjects at both sites.ResultsAnalysis of variance (ANOVA) and region of interest (ROI) analysis confirmed that site did not play a significant role in explaining variance in our large fMRI dataset. Effect size analysis shows that between‐subject differences account for nearly 10 times more variance than site effects.ConclusionWe show that quantitative comparisons of contrast estimates derived from cognitive experiments can reliably be compared across two sites. This allows us to establish an effective platform for comparing group differences between two sites using fMRI when group effects are potentially confounded with site, as in the study of neurocultural differences between countries or multicenter clinical trials. J. Magn. Reson. Imaging 2008;28:21–28. © 2008 Wiley‐Liss, Inc.
3T MR with diffusion tensor imaging and single‐voxel spectroscopy in giant axonal neuropathy
Authors: Brenner Christiana , Speck‐Martins Carlos Eduardo , Farage Luciano , Barker Peter B. 
Published: June 2008

AbstractMagnetic resonance imaging (MRI), diffusion tensor imaging (DTI), and MR spectroscopy (MRS) data were obtained in a patient with giant axonal neuropathy (GAN) and compared to a control group. Fractional anisotropy (FA) and apparent coefficient diffusion (ADC) data were obtained from specific white matter tracts including the corticospinal tracts (CST), corpus callosum (CC), optic radiations (OR), and middle cerebellar peduncle (MCP). Analysis of the MRS was performed. DTI parameters and MRS results were correlated with the neuropathological findings described for GAN. No significant difference between the FA of the CC of the patient and the control group was found. However, there was a significant difference between the FA of the CST, OR, and MCP of the patient and the control group. The ADC values for all tracts of the patient were significantly increased. N‐acetylaspartate to creatine (NAA/Cr) and N‐acetylaspartate to choline (NAA‐Cho) (choline) metabolite ratios were slightly decreased and choline to creatine (Cho/Cr) and myo‐inositol to creatine (Ins/Cr) metabolite ratios were increased in the parietal gray and white matter of the patient as compared to the control group. Cerebellar involvement was less evident. The DTI and MRS findings suggest myelin and axonal damage. J. Magn. Reson. Imaging 2008;28:236–241. © 2008 Wiley‐Liss, Inc.
Impact of heart rate variability in patients with normal sinus rhythm on image quality in coronary magnetic angiography
Authors: Tangcharoen Tarinee , Jahnke Cosima , Koehler Uwe , Schnackenburg Bernhard , Klein Christoph , Fleck Eckart , Nagel Eike 
Published: June 2008

AbstractPurposeTo evaluate the influence of heart rate variability on image quality in patients with suspected coronary artery disease during magnetic resonance coronary angiography (MRCA).Materials and MethodsThe coronary images from 70 patients who underwent target‐volume MRA were retrospectively analyzed. Two independent observers evaluated image quality using a score from 0 (nonvisible) to 4 (excellent quality). Images were grouped into good (score > 2) and poor image quality (score 0–2). Five parameters (effective scan duration, navigator efficiency, mean heart rate, acquisition window, and heart rate variability) were evaluated.ResultsIn all, 56 of the 70 patients (80%) were scored as good and 14 as poor image quality. Only the navigator efficiency, heart rate variability, and acquisition window showed statistically significant for the prediction of image quality, with navigator efficiency being the strongest predictor. Subgroup analysis showed that patients with navigator efficiency >60% had good image quality independent of the heart rate variability. In patients with navigator efficiency ≤60%, heart rate variability is the only remaining significant parameter (P = 0.03).ConclusionNavigator efficiency was the most important predictor of MRCA image quality. Heart rate variability is the most important predictor of image quality in patients with a navigator efficiency ≤60%. J. Magn. Reson. Imaging 2008;28:74–79. © 2008 Wiley‐Liss, Inc.
A simplified method for extracting water‐extractable arabinoxylans from wheat flour
Authors: Ganguli Nishath K , Turner Matthew A 
Published: June 2008

AbstractBACKGROUND: Water‐extractable arabinoxylan (WEAX) is a minor constituent of wheat grain which influences the properties of wheat dough and its end products while conferring numerous health benefits. Consequently, various applications have been proposed for it in foodstuffs. Fortification of food products with pure WEAX extracts represents a simple means to evaluate its effect in these systems. However, rapid methods to isolate relatively pure WEAX are not available. This study aimed to develop a rapid, technically simple means to extract relatively pure WEAX on a small scale.RESULTS: A simplified process was developed to extract WEAX from wheat flour. After heating, flour WEAX was extracted with water and starch was eliminated by digestion with amyloglucosidase. Most of the protein was removed by adsorption to bentonite and precipitation with 65% ethanol. The final product generated by the developed method consisted of 93 ± 4% arabinoxylan. The WEAX yield was 0.43 ± 0.02% (0.43 ± 0.02 g WEAX/100 g of starting flour) which is higher than that of other methods that generate WEAX of similar purity.CONCLUSION: This method provides a technically simple means to perform small‐scale isolation of WEAX that contains no detectable contaminating protein. This attribute renders it a preferred input for studies assessing the impact of WEAX fortification on food product quality. Copyright © 2008 Society of Chemical Industry
Assessment of compositional changes during ripening of transgenic papaya modified for protection against papaya ringspot virus
Authors: Roberts Madeen , Minott Donna A , Tennant Paula F , Jackson Jose C 
Published: June 2008

AbstractBACKGROUND: Papaya (Carica papaya L.) production is limited by over 20 viruses, the most damaging of which is papaya ringspot virus (PRSV). Owing to a lack of suitable PRSV‐resistant sources in Carica germplasm, transgenic resistance using the coat protein (cp) gene of a local PRSV strain is being developed to manage the disease in Jamaica. For assurance of food safety, the nutritional and antinutritional composition of transgenic papayas during ripening was compared with that of unmodified control samples.RESULTS: Mature unripe fruits of transgenic and non‐transgenic papayas were repeatedly harvested and stored at room temperature for 1 week periods, during which random samples were assessed. With the exception of one transgenic line, no significant differences (P > 0.05) were observed in selected nutrients and antinutrients between the control and test samples at three stages of maturity, although a few random variations were noted.CONCLUSION: Transformation with viral cp gene and two marker genes did not produce any major unintended alterations in either the nutritional or the antinutritional composition of transgenic papayas. These findings must be compared with other physicochemical and safety assessments to provide a scientific basis for concluding substantial equivalence with conventional papayas available on the market in Jamaica. Copyright © 2008 Society of Chemical Industry
The prevalence of Parkinson's disease in rural Tanzania
Authors: Dotchin Catherine , Msuya Olivia , Kissima John , Massawe John , Mhina Ali , Moshy Addess , Aris Eric , Jusabani Ahmed , Whiting David , Masuki Gabriel , Walker Richard 
Published: June 2008

AbstractThe prevalence of Parkinson's disease (PD) varies worldwide from 7 to 450 per 100,000, and appears low in sub‐Saharan Africa (SSA) but few data exist. We conducted a prevalence study of PD in rural Tanzania. A door‐to‐door study was conducted in the Hai district project area (population 161,071), using a screening questionnaire followed by structured history and examination of positive responders. Diagnosis was based on the UK PD Society Brain Bank Criteria. 33 (23 men) cases of PD were detected, with mean age 74 years (range 38–94). One patient died before the prevalence date. 78% were previously undiagnosed and untreated. Mean duration of symptoms was 5 years, and median Hoehn and Yahr stage 3. Crude prevalence rates were 30/100,000 (men), 11/100,000 (women) and 20/100,000 (combined). The direct age‐standardized prevalence rates compared with the UK population were 64/100,000 (men), 20/100,000 (women) and 40/100,000 (combined). These rates are higher than previously reported from SSA, but still lower than the developed world. Many PD patients in SSA may never be diagnosed or treated, with consequent reduction in their life expectancy and quality of life. With the world population ageing PD is predicted to become an increasing problem. © 2007 Movement Disorder Society
The current clinical management of Huntington's disease
Authors: Phillips Wendy , Shannon Kathleen M. , Barker Roger A. 
Published: June 2008

AbstractHuntington's disease is a neurodegenerative condition, characterized by movement disorders, cognitive decline, and psychiatric disturbance. We review the pharmacological management of the various movement disorders associated with the disease, the cognitive decline and the commonly encountered behavioral disturbances. We discuss the nonclassical features of the disease, important in the management of these patients. Nonpharmacological support including genetic counseling and therapy and the importance of palliative care are also addressed. Finally, experimental approaches that may soon impact upon clinical practice are discussed. © 2008 Movement Disorder Society
A novel mutation of the ε‐sarcoglycan gene in a Chinese family with myoclonus‐dystonia syndrome
Authors: Chen Xue‐Ping , Zhang Yang‐Wei , Zhang Shu‐Shan , Chen Qin , Burgunder Jean‐Marc , Wu Shu‐Hui , Yang Yuan , Luo Zu‐Ming , Shang Hui‐Fang 
Published: June 2008

AbstractIn a Chinese myoclonus‐dystonia syndrome (MDS) family presented with a phenotype including a typical MDS, cervical dystonia, and writer's cramp, genetic analyses revealed a novel 662 + 1insG heterozygous mutation in exon 5 in the ε‐sarcoglycan (SGCE) gene, leading to a frameshift with a down stream stop codon. Low SGCE mRNA levels were detected in the mutation carriers by real‐time PCR, suggesting that the nonsense mutation might interference with the stability of SGCE mRNA. This is the first report on Chinese with a SGCE mutation leading to MDS. Our data support the fact that same mutation of SGCE gene can lead to a varied phenotype, even in the same family. © 2008 Movement Disorder Society
Measurement of T1 and T2 in the cervical spinal cord at 3 tesla
Authors: Smith Seth A. , Edden Richard A.E. , Farrell Jonathan A.D. , Barker Peter B. , Van Zijl Peter C.M. 
Published: June 2008

AbstractT1 and T2 were measured for white matter (WM) and gray matter (GM) in the human cervical spinal cord at 3T. T1 values were calculated using an inversion‐recovery (IR) and B1‐corrected double flip angle gradient echo (GRE) and show significant differences (p = 0.002) between WM (IR = 876 ± 27 ms, GRE = 838 ± 54 ms) and GM (IR = 973 ± 33 ms, GRE = 994 ± 54 ms). IR showed significant difference between lateral and dorsal column WM (863 ± 23 ms and 899 ± 18 ms, respectively, p = 0.01) but GRE did not (p = 0.40). There was no significant difference (p = 0.31) in T2 between WM (73 ± 6 ms) and GM (76 ± 3 ms) or between lateral and dorsal columns (lateral: 73 ± 6 ms, dorsal: 72 ± 7 ms, p = 0.59). WM relaxation times were similar to brain structures with very dense fiber packing (e.g., corpus callosum), while GM values resembled deep GM in brain. Optimized sequence parameters for maximal contrast between WM and GM, and between WM and cerebrospinal fluid (CSF) were derived. Since the spinal cord has rostral‐caudal symmetry, we expect these findings to be applicable to the whole cord. Magn Reson Med 60:213–219, 2008. © 2008 Wiley‐Liss, Inc.
Spatiotemporal magnetic field monitoring for MR
Authors: Barmet Christoph , Zanche Nicola De , Pruessmann Klaas P. 
Published: June 2008

AbstractMR experiments frequently rely on signal encoding by the application of magnetic fields that vary in both space and time. The accurate interpretation of the resulting signals often requires knowledge of the exact spatiotemporal field evolution during the experiment. To better fulfill this need, a new approach is presented that enables measuring the field evolution concurrently with any MR sequence. Miniature NMR probes are used to monitor the MR phase evolution around the object under investigation. Based on these data, a global phase model is calculated that can then be used as a basis for processing the actual image or spectroscopic data. The new method is demonstrated by MRI of a phantom, using spin‐warp, spiral, and EPI trajectories. Throughout, the monitoring results enabled highly accurate image reconstruction, even in the presence of massive gradient imperfections. Magn Reson Med 60:187–197, 2008. © 2008 Wiley‐Liss, Inc.
Evaluation of an AIF correction algorithm for dynamic susceptibility contrast‐enhanced perfusion MRI
Authors: Brunecker Peter , Endres Matthias , Nolte Christian H. , Schultze Jörg , Wegener Susanne , Jungehülsing Gerhard Jan , Müller Bianca , Kerskens Christian M. , Fiebach Jochen B. , Villringer Arno , Steinbrink Jens 
Published: June 2008

AbstractFor longitudinal studies in patients suffering from cerebrovascular diseases the poor reproducibility of perfusion measurements via dynamic susceptibility‐weighted contrast‐enhanced MRI (DSC‐MRI) is a relevant concern. We evaluate a novel algorithm capable of overcoming limitations in DSC‐MRI caused by partial volume and saturation issues in the arterial input function (AIF) by a blood flow stimulation‐study. In 21 subjects, perfusion parameters before and after administration of blood flow stimulating L‐arginine were calculated utilizing a block‐circulant singular value decomposition (cSVD). A total of two different raters and three different rater conditions were employed to select AIFs: Besides 1) an AIF selection by an experienced rater, a beginner rater applied a steady state‐oriented strategy, returning; 2) raw; and 3) corrected AIFs. Highly significant changes in regional cerebral blood flow (rCBF) by 9.0% (P < 0.01) could only be found when the AIF correction was performed. To further test for improved reproducibility, in a subgroup of seven subjects the baseline measurement was repeated 6 weeks after the first examination. In this group as well, using the correction algorithm decreased the SD of the difference between the two baseline measurements by 42%. Magn Reson Med 60:102–110, 2008. © 2008 Wiley‐Liss, Inc.
Estimating intracellular lithium in brain in vivo by localized 7Li magnetic resonance spectroscopy
Authors: Komoroski Richard A. , Pearce John M. 
Published: June 2008

AbstractThe therapeutic mechanism of action of lithium (Li) in bipolar disorder is unknown. While Li is presumed to work intracellularly in the brain, the fraction of intracellular Li in the brain in vivo is not known. It has not yet been possible to determine, directly and noninvasively, the intra‐ to extracellular distribution of Li in human brain in vivo. Lithium‐7 (7Li) MR is the only technique available for measuring noninvasively the concentration of Li in the brain in vivo. Here the individual components of biexponential 7Li transverse (T2) relaxation in rat brain in vivo are identified with intra‐ and extracellular Li, and used to estimate its compartmental distribution. Intracellular T2 was 14.6 ± 6.9 ms, while extracellular T2 was 160 ± 52 ms in nine rats. The fraction of intracellular brain Li ranged from 37% to 75% (mean: 63 ± 11%). Further, the biexponential T2 results provided the basis for estimating Li compartmental distribution from monoexponential T2 decays using a simple linear approximation. The fraction of intracellular Li estimated from monoexponential T2 decays agreed with the corresponding biexponential estimates in most cases. Magn Reson Med 60:21–26, 2008. © 2008 Wiley‐Liss, Inc.