bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cardiac troponin T and creatine kinase predict mid‐term infarct size and left ventricular function after acute myocardial infarction: A cardiac MR study
Authors: Mayr Agnes , Mair Johannes , Klug Gert , Schocke Michael , Pedarnig Kathrin , Trieb Thomas , Pachinger Otmar , Jaschke Werner , Metzler Bernhard 
Published: March 2011

AbstractPurpose:To assess the relation of cardiac troponin T (cTnT) and creatine kinase (CK) release with infarct size and left ventricular function evaluated during the subacute phase as well as four months after acute myocardial infarction (AMI) by contrast‐enhanced MRI (CE‐MRI).Materials and Methods:CMR of 80 patients (68 male, mean age 54.2 ± 11.7 years) was performed within 8 days and 4 months after first acute ST‐elevation AMI with successful primary angioplasty. CK and cTnT concentrations were determined serially from admission to day 4 after symptom onset.Results:All single time‐points, estimated average release and peak concentrations of CK and cTnT markers correlated significantly with acute and mid‐term infarct size (r = 0.43 to 0.79, all P < 0.001), ejection fraction (EF%) (r = −0.42 to −0.58, all P < 0.002) as well as with end‐systolic volume (ESV) (r = 0.32 to 0.57, all P < 0.002) at all times of assessment. Patients with cTnT concentrations below the cutoff value of 3.26 μg/L measured 48 h after AMI‐related symptom onset had a significant improvement in global (EF: P < 0.0001) myocardial function during the study period, whereas in those with cTnT ≥ 3.26 μg/L, functional recovery did not occur (P = 0.09).Conclusion:All single, mean and maximum concentrations of cTnT and CK measured within the first 4 days after AMI permit an accurate prediction of infarct size and left ventricular function as determined in the acute phase as well as four months after AMI by CE‐MRI. J. Magn. Reson. Imaging 2011;33:847–854. © 2011 Wiley‐Liss, Inc.
Gadobenate dimeglumine‐enhanced liver MR imaging in cirrhotic patients: Quantitative and qualitative comparison of 1‐hour and 3‐hour delayed images
Authors: Jeong Woo Kyoung , Byun Jae Ho , Lee Seung Soo , Won Hyung Jin , Kim Kyoung Won , Shin Yong Moon , Kim Pyo Nyun , Lee Moon‐Gyu 
Published: March 2011

AbstractPurpose:To compare the image quality and diagnostic performance of 1‐ and 3‐h delayed‐phase MR images (DPIs) after gadobenate dimeglumine injection in detecting small hepatocellular carcinomas (HCCs) in cirrhotic patients.Materials and Methods:Relative enhancement of the liver (REliver) and HCC (REHCC) and liver‐to‐lesion contrast‐to‐noise ratio (CNR) of HCC were measured quantitatively on 1‐ and 3‐h DPIs in 65 patients with 88 HCCs. For qualitative analysis, two radiologists independently evaluated three image sets in 19 patients with 25 HCCs ≤2 cm and in 16 controls without HCCs: conventional liver MR without DPI (set A), adding 1‐h DPI (set B), and adding 3‐h DPI (set C), using a 5‐point scale for diagnosing small HCCs. Diagnostic performance for small HCCs was analyzed using the alternative free‐response receiver operating characteristic method.Results:Mean REliver (P = 0.013) and REHCC (P < 0.001) were significantly higher on 1‐h than on 3‐h DPI, whereas CNR was significantly higher on 3‐h than on 1‐h DPI (P = 0.001). Observer‐averaged figure of merit (FOM) was significantly higher for set C than for set A (0.942 versus 0.883; P = 0.013).Conclusion:In cirrhotic patients, 3‐h DPI provides a higher liver‐to‐lesion contrast and a better diagnostic performance for small HCCs than 1‐h DPI. J. Magn. Reson. Imaging 2011;33:889–897. © 2011 Wiley‐Liss, Inc.
Imaging of the wrist at 1.5 tesla using isotropic three‐dimensional fast spin echo cube
Authors: Stevens Kathryn J. , Wallace Charles G. , Chen Weitian , Rosenberg Jarrett K. , Gold Garry E. 
Published: March 2011

AbstractPurpose:To compare three‐dimensional fast spin echo Cube (3D‐FSE‐Cube) with conventional 2D‐FSE in MR imaging of the wrist.Materials and Methods:The wrists of 10 volunteers were imaged in a 1.5 Tesla MRI scanner using an eight‐channel wrist coil. The 3D‐FSE‐Cube images were acquired in the coronal plane with 0.5‐mm isotropic resolution. The 2D‐FSE images were acquired in both coronal and axial planes for comparison. An ROI was placed in fluid, cartilage, and muscle for SNR analysis. Comparable coronal and axial images were selected for each sequence, and paired images were randomized and graded for blurring, artifact, anatomic details, and overall image quality by three blinded musculoskeletal radiologists.Results:SNR of fluid, cartilage and muscle at prescribed locations were higher using 3D‐FSE‐Cube, without reaching statistical significance. Fluid–cartilage CNR was also higher with 3D‐FSE‐Cube, but not statistically significant. Blurring, artifact, anatomic details, and overall image quality were significantly better on coronal 3D‐FSE‐Cube images (P < 0.001), but significantly better on axial 2D‐FSE images compared with axial 3D‐FSE‐Cube reformats (P < 0.01).Conclusion:Isotropic data from 3D‐FSE‐Cube allows reformations in arbitrary scan planes, which may make multiple 2D acquisitions unnecessary, and improve depiction of complex wrist anatomy. However, axial reformations suffer from blurring, likely due to T2 decay during the long echo train, limiting overall image quality in this plane. J. Magn. Reson. Imaging 2011;33:908–915. © 2011 Wiley‐Liss, Inc.
Dynamic nuclear polarization system output volume reduction using inert fluids
Authors: Peterson Eric T. , Gordon Jeremy W. , Erickson Matthew G. , Fain Sean B. , Rowland Ian J. 
Published: March 2011

AbstractPurpose:To present a method for significantly increasing the concentration of a hyperpolarized compound produced by a commercial dynamic nuclear polarization (DNP) polarizer, enabling the polarization process to be more suitable for preclinical applications.Materials and Methods:Using a HyperSense DNP polarizer, we investigated the combined use of perfluorocarbon and water to warm and dissolve the hyperpolarized material from the polarization temperature of 1.4K to produce material at temperatures suitable for injection.Results:By replacing 75% of the water in the dissolution volume with a chemically and biologically inert liquid that is immiscible with water, the injection volume can be reduced 4‐fold. Rapid separation of the water and perfluorocarbon mixture enables the aqueous layer containing polarized material to be easily and rapidly collected.Conclusion:The approach provides a significantly increased concentration of compound in a volume for injection that is more appropriate for small animal studies. This is demonstrated for 13C‐labeled pyruvic acid and 13C‐labeled succinate, but may be applied to the majority of nuclei and compounds hyperpolarized by the DNP method. J. Magn. Reson. Imaging 2011;33:1003–1008. © 2011 Wiley‐Liss, Inc.
Acute hemorrhagic leukoencephalitis with severe brainstem and spinal cord involvement: MRI features with neuropathological confirmation
Authors: Pinto Pedro S. , Taipa Ricardo , Moreira Bruno , Correia Carlos , Melo‐Pires Manuel 
Published: March 2011

AbstractAcute hemorrhagic leukoencephalitis (AHLE) is a rare and fulminant demyelinating disease considered to be the most severe form of acute disseminated encephalomyelitis (ADEM). A 70‐year‐old man was admitted to our emergency department (ED) after 1 week of unspecific abdominal symptoms and moderate fever in the first 3 days. Within the ED he developed a rapid onset coma and flaccid tetraparesis. Cerebrospinal fluid (CSF) analysis showed mild polymorphonuclear pleocytosis and magnetic resonance imaging (MRI) revealed supratentorial focal white matter lesions and diffuse involvement of the medulla and spinal cord. A presumptive diagnosis of ADEM was made and the patient was treated with corticosteroids followed by intravenous immunoglobulin. His neurological state did not improve and the MRI on day 8 after admission showed an increased number of lesions, mainly in the brainstem, with hemorrhagic foci. The patient died the following day and pathological features confirmed the diagnosis of AHLE. This is a unique presentation of a rare disease with detailed MRI characteristics and pathological confirmation. Although this condition is usually fatal, early recognition and aggressive therapeutic management can facilitate survival. J. Magn. Reson. Imaging 2011;33:957–961. © 2011 Wiley‐Liss, Inc.
Automated brain extraction from T2‐weighted magnetic resonance images
Authors: Datta Sushmita , Narayana Ponnada A. 
Published: March 2011

AbstractPurpose:To develop and implement an automated and robust technique to extract brain from T2‐weighted images.Materials and Methods:Magnetic resonance imaging (MRI) was performed on 75 adult volunteers to acquire dual fast spin echo (FSE) images with fat‐saturation technique on a 3T Philips scanner. Histogram‐derived thresholds were derived directly from the original images followed by the application of regional labeling, regional connectivity, and mathematical morphological operations to extract brain from axial late‐echo FSE (T2‐weighted) images. The proposed technique was evaluated subjectively by an expert and quantitatively using Bland–Altman plot and Jaccard and Dice similarity measures.Results:Excellent agreement between the extracted brain volumes with the proposed technique and manual stripping by an expert was observed based on Bland–Altman plot and also as assessed by high similarity indices (Jaccard: 0.9825 ± 0.0045; Dice: 0.9912 ± 0.0023).Conclusion:Brain extraction using the proposed automated methodology is robust and the results are reproducible. J. Magn. Reson. Imaging 2011;33:822–829. © 2011 Wiley‐Liss, Inc.
Assessment of flow instabilities in the healthy aorta using flow‐sensitive MRI
Authors: Stalder Aurélien F. , Frydrychowicz Alex , Russe Max F. , Korvink Jan G. , Hennig Jürgen , Li Kuncheng , Markl Michael 
Published: March 2011

AbstractPurpose:To assess blood flow velocities and spatial distribution of aortic Reynolds numbers in vivo using flow‐sensitive magnetic resonance imaging (MRI) and probe for flow instabilities along the aorta based on an empirical model for physiological pulsatile blood flow.Materials and Methods:Thirty young healthy volunteers were examined by flow‐sensitive MRI at eight imaging planes distributed along the thoracic aorta. Flow, Womersley, Strouhal, Reynolds, and critical Reynolds numbers were calculated and used to assess the presence of flow instabilities.Results:The average peak Reynolds number was higher in the ascending (≈4500) and descending aorta (≈4200) than in the aortic arch (≈3400). According to the calculated critical Reynolds numbers, flow instabilities were prominent in the ascending (14/30 volunteers) and descending aorta (22/30 volunteers) but not in the aortic arch (3/30 volunteers). A significant difference (P < 0.05) in supracritical peak Reynolds numbers was observed between genders. The supracritical Reynolds number, indicating flow instabilities, significantly correlated (P < 0.05) with body weight (r = 0.34), aortic diameter (r = 0.48), and cardiac output (r = 0.53).Conclusion:Flow‐sensitive MRI was used to indirectly assess the presence of flow instabilities in vivo. The results in volunteers indicate the presence of flow instabilities in the young healthy aorta with a higher prevalence for men than women. J. Magn. Reson. Imaging 2011;33:839–846. © 2011 Wiley‐Liss, Inc.
T1 independent, T2* corrected chemical shift based fat–water separation with multi‐peak fat spectral modeling is an accurate and precise measure of hepatic steatosis
Authors: Hines Catherine D.G. , Frydrychowicz Alex , Hamilton Gavin , Tudorascu Dana L. , Vigen Karl K. , Yu Huanzhou , McKenzie Charles A. , Sirlin Claude B. , Brittain Jean H. , Reeder Scott B. 
Published: March 2011

AbstractPurpose:To determine the precision and accuracy of hepatic fat‐fraction measured with a chemical shift‐based MRI fat‐water separation method, using single‐voxel MR spectroscopy (MRS) as a reference standard.Materials and Methods:In 42 patients, two repeated measurements were made using a T1‐independent, T‐corrected chemical shift‐based fat‐water separation method with multi‐peak spectral modeling of fat, and T2‐corrected single voxel MR spectroscopy. Precision was assessed through calculation of Bland‐Altman plots and concordance correlation intervals. Accuracy was assessed through linear regression between MRI and MRS. Sensitivity and specificity of MRI fat‐fractions for diagnosis of steatosis using MRS as a reference standard were also calculated.Results:Statistical analysis demonstrated excellent precision of MRI and MRS fat‐fractions, indicated by 95% confidence intervals (units of absolute percent) of [−2.66%,2.64%] for single MRI ROI measurements, [−0.81%,0.80%] for averaged MRI ROI, and [−2.70%,2.87%] for single‐voxel MRS. Linear regression between MRI and MRS indicated that the MRI method is highly accurate. Sensitivity and specificity for detection of steatosis using averaged MRI ROI were 100% and 94%, respectively. The relationship between hepatic fat‐fraction and body mass index was examined.Conclusion:Fat‐fraction measured with T1‐independent T‐corrected MRI and multi‐peak spectral modeling of fat is a highly precise and accurate method of quantifying hepatic steatosis. J. Magn. Reson. Imaging 2011;33:873–881. © 2011 Wiley‐Liss, Inc.
Reproducibility of flow and wall shear stress analysis using flow‐sensitive four‐dimensional MRI
Authors: Markl Michael , Wallis Wolf , Harloff Andreas 
Published: March 2011

AbstractPurpose:To systematically investigate the scan–rescan reproducibility and observer variability of flow‐sensitive four‐dimensional (4D) MRI in the aorta for the assessment of blood flow and global and segmental wall shear stress.Materials and Methods:ECG and respiration‐synchronized flow‐sensitive 4D MRI data (spatio‐temporal resolution = 1.7 × 2.0 × 2.2 mm3/40.8 ms) were acquired in 12 healthy volunteers. To analyze scan–rescan variability, flow‐sensitive 4D MRI was repeated in 10 volunteers during a second visit. Data analysis included calculation of time‐resolved and total flow, peak systolic velocity, and regional and global wall shear stress (WSS) in up to 24 analysis planes distributed along the aorta.Results:Scan–rescan, inter‐observer, and intra‐observer agreement was excellent for the calculation of total flow and peak systolic velocity (mean differences <5% of the average flow parameter). Global WSS demonstrated moderate agreement and increased variability regarding wall shear stress (scan‐rescan, inter‐observer, and intra‐observer agreement; mean differences <10% of the average WSS parameters). The segmental distribution of wall shear stress in the thoracic aorta could reliably be reproduced (r > 0.87; P < 0.001) for different observers and examinations.Conclusion:Flow‐sensitive 4D MRI‐based analysis of aortic blood flow can be performed with good reproducibility. Robustness of global and regional WSS quantification was limited, but spatio‐temporal WSS distributions could reliably be replicated. J. Magn. Reson. Imaging 2011;33:988–994. © 2011 Wiley‐Liss, Inc.
Decreased SH3BP2 inhibits osteoclast differentiation and function
Authors: Kawamoto Teruya , Fan Chun , Gaivin Robert J. , Levine Michael A. , Lietman Steven A. 
Published: March 2011

AbstractGermline mutations in SH3BP2 gene have been identified in patients with cherubism, a skeletal disorder characterized by excessive osteoclastic bone resorption that is limited to the mandible and maxilla. We previously demonstrated that SH3BP2 overexpression in Raw264.7 cells increased RANKL‐induced osteoclastogenesis. Here, we examine the effect of decreased SH3BP2 on osteoclastogenesis. shRNA knockdown of SH3BP2 decreased PLCγ2 phosphorylation and NFATc1 expression, and reduced the expression of osteoclast‐specific genes. In BMMs knockdown of SH3BP2 led to reductions in both the number and the surface area of TRAP positive and multinucleated osteoclasts. Bone resorptive activity was also dramatically blocked by shRNA knockdown of SH3BP2. Similarly Sh3bp2(−/−) deficient mice BMMs formed smaller osteoclasts that stained less with TRAP than wild‐type mice. Taken together, this study demonstrates that SH3BP2 knockdown significantly decreases osteoclast differentiation and function. These results suggest that SH3BP2 plays a critical role in osteoclastogenesis and is a potential target for suppression of pathologic bone resorption. © 2011 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29: 1521–1527, 2011
Combining the evidence using stable weights
Authors: Kulinskaya Elena , Morgenthaler Stephan , Staudte Robert G. 
Published: March 2011

AbstractIn a meta‐analysis one seeks to combine the results of several studies in order to improve the accuracy of decisions. Here we compare by simulation four methods for combining estimates of the risk difference, namely the Cochran and Mantel–Haenszel (MH) methods, the inverse‐variance weights approach and a recent variance‐stabilized weights approach. Both the level and power of corresponding test statistics, as well as the coverage of related confidence intervals are compared over a wide range of sample size and parameter configurations.We found that the inverse‐variance weights methodology is unreliable and is not recommended, while for equal risks, the Cochran test and the associated confidence intervals are the most reliable. Under alternatives of unequal risks, the coverage probabilities of the variance‐stabilized confidence intervals are almost uniformly more reliable than those based on other methods except when the average risk is small in which case the MH confidence intervals are preferable. Copyright © 2011 John Wiley & Sons, Ltd.
The impact of amount of bone resection on uncemented prosthesis failure in patients with a distal femoral tumor
Authors: Song Won Seok , Kong Chang‐Bae , Jeon Dae‐Geun , Cho Wan Hyeong , Kim Jung Ryul , Cho Yool , Lee Soo‐Yong 
Published: March 2011

AbstractBackground and ObjectivesPrevious reports on the correlation between the amount of bone resection and prosthetic failure might be confounded by variability in the amount of soft tissue resected and by the mode of prosthesis fixation.MethodsWe analyzed 117 patients who underwent intra‐articular resection and cementless modular tumor prosthetic reconstruction for a distal femoral tumor. Mean follow‐up duration was 95 months (range, 15–271 months). Associations between the prognostic variables and prosthesis survival were assessed. A receiver operating characteristic (ROC) curve was plotted for resection percentage to predict prosthetic failure.ResultsProstheses were removed in 35 (30%) patients for; infection (17), local recurrence (5), loosening (7), stem fracture (4), or periprosthetic fracture (2). The 10‐year prosthetic survivals of the 117 implants were 65.2 ± 5.4%. A percentage bone resection (>40%) was found to be associated with mechanical prosthesis failure by multivariate analysis (P = 0.003). ROC curve analysis demonstrated that an optimal cut‐off point of 43% for resection percentage had a sensitivity of 95.9% and a specificity of 45.5% for predicting mechanical prosthesis failure.ConclusionsInfection is the major cause of prosthetic failure, and amount of bone resection is negatively correlated with implant longevity. J. Surg. Oncol. 2011;104:192–197. © 2011 Wiley‐Liss, Inc.
Fire, grazing history, lichen abundance, and winter distribution of caribou in Alaska's taiga
Authors: Collins William B. , Dale Bruce W. , Adams Layne G. , Mcelwain Darien E. , Joly Kyle 
Published: March 2011

AbstractIn the early 1990s the Nelchina Caribou (Rangifer tarandus) Herd (NCH) began a dramatic shift to its current winter range, migrating at least an additional 100 km beyond its historic range. We evaluated the impacts of fire and grazing history on lichen abundance and subsequent use and distribution by the NCH. Historic (prior to 1990) and current (2002) winter ranges of the NCH had similar vascular vegetation, lichen cover (P = 0.491), and fire histories (P = 0.535), but the former range had significantly less forage lichen biomass as a result of grazing by caribou. Biomass of forage lichens was twice as great overall (P = 0.031) and 4 times greater in caribou selected sites on the current range than in the historic range, greatly increasing availability to caribou. Caribou on the current range selected for stands with >20% lichen cover (P < 0.001), greater than 1,250 kg/ha (P < 0.001) forage lichen biomass and stands older than 80 yr postfire (P < 0.001). After fires, forage lichen cover and biomass seldom recovered sufficiently to attract caribou grazing until after ≥60 yr, and, as a group, primary forage lichen species did not reach maximum abundance until 180 yr postfire. Recovery following overgrazing can occur much more quickly because lichen cover, albeit mostly fragments, and organic substrates remain present. Our results provide benchmarks for wildlife managers assessing condition of caribou winter range and predicting effects of fires on lichen abundance and caribou distribution. Of our measurements of cover and biomass by species, densities and heights of trees, elevation, slope and aspect, only percentage cover by Cladonia amaurocraea, Cladina rangiferina, Flavocetraria cuculata, and lowbush cranberry (Vaccinium vitis‐idaea) were necessary for predicting caribou use of winter range. © 2011 The Wildlife Society
Genetic assessment of paternity and relatedness in a managed population of cougars
Authors: Onorato Dave , Desimone Rich , White Craig , Waits Lisette P. 
Published: March 2011

AbstractUnderstanding the social dynamics of large carnivores is critical to effective conservation and management planning. We made the first attempt to delineate both paternity and relatedness for a population of cougar (Puma concolor) using microsatellite data. We analyzed a long‐term genetic dataset collected from a hunted population in the Garnet Mountains of western Montana. We assigned paternity for 62.5% of litters sampled using both exclusion and likelihood analyses. Attempts at reconstructing unsampled paternal genotypes resulted in delineating possible sires for 8 more litters. Sires were on average younger than reported for males involved in pairings assessed via field data in other cougar populations. Although most mating pairs were unrelated, 5 of 17 pairings involved cougars with levels of relatedness corresponding to half‐sibling and full‐sibling or parent offspring relationship (r = 0.215–0.575). Relatedness among adult and subadult males was higher than relatedness levels among adult and subadult females. Relatedness among males in the Garnet population differed from patterns hypothesized to occur under male‐biased dispersal theories for cougars. The long‐term impact of the turnover of resident cougars in hunted populations is still unclear and warrants additional research. Our results highlight the utility of monitoring cougar demographic parameters using a combination of genetic and field data that in turn may assist managers with determining cougar harvest quotas or strategies, harvest seasons, sustainable harvest, and the appropriate management level of cougar populations. © 2011 The Wildlife Society.