bluuebunny/crossref_metadata_2025_split huggingface dataset:
Whole‐heart coronary magnetic resonance angiography at 3.0T using short‐TR steady‐state free precession, vastly undersampled isotropic projection reconstruction
Authors: Xie Jingsi , Lai Peng , Bhat Himanshu , Li Debiao 
Published: April 2010

AbstractPurposeTo evaluate the feasibility of improving 3.0T steady‐state free precession (SSFP) whole‐heart coronary magnetic resonance angiography (MRA) using short‐TR (repetition time) VIPR (vastly undersampled isotropic projection reconstruction).Materials and MethodsSSFP is highly sensitive to field inhomogeneity. VIPR imaging uses nonselective radiofrequency pulses, allowing short TR and reduced banding artifacts, while achieving isotropic 3D resolution. Coronary artery imaging was performed in nine healthy volunteers using SSFP VIPR. TR was reduced to 3.0 msec with an isotropic spatial resolution of 1.3 × 1.3 × 1.3 mm3. Image quality, vessel sharpness, and lengths of major coronary arteries were measured. Comparison between SSFP using Cartesian trajectory and SSFP using VIPR trajectory was performed in all volunteers.ResultsShort‐TR SSFP VIPR resulted in whole‐heart images without any banding artifacts, leading to excellent coronary artery visualization. The average image quality score for VIPR‐SSFP was 3.12 ± 0.42 out of four while that for Cartesian SSFP was 0.92 ± 0.61. A significant improvement (P < 0.05) in image quality was shown by Wilcoxon comparison. The visualized coronary artery lengths for VIPR‐SSFP were: 10.13 ± 0.79 cm for the left anterior descending artery (LAD), 7.90 ± 0.91 cm for the left circumflex artery (LCX), 7.50 ± 1.65 cm for the right coronary artery (RCA), and 1.84 ± 0.23 cm for the left main artery (LM). The lengths statistics for Cartesian SSFP were 1.57 ± 2.02 cm, 1.54 ± 1.93 cm, 0.94 ± 1.17 cm, 0.46 ± 0.53 cm, respectively. The image sharpness was also increased from 0.61 ± 0.13 (mm−1) in Cartesian‐SSFP to 0.81 ± 0.11 (mm−1) in VIPR‐SSFP.ConclusionWith VIPR trajectory the TR is substantially decreased, reducing the sensitivity of SSFP to field inhomogeneity and resulting in whole‐heart images without banding artifacts at 3.0T. Image quality improved significantly over Cartesian sampling. J. Magn. Reson. Imaging 2010; 31:1230–1235. © 2010 Wiley‐Liss, Inc.
Accuracy and repeatability of fourier velocity encoded M‐mode and two‐dimensional cine phase contrast for pulse wave velocity measurement in the descending aorta
Authors: Taviani Valentina , Patterson Andrew J. , Graves Martin J. , Hardy Christopher J. , Worters Pauline , Sutcliffe Michael P.F. , Gillard Jonathan H. 
Published: April 2010

AbstractPurpose:To assess the accuracy and repeatability of Fourier velocity encoded (FVE) M‐mode and two‐dimensional (2D) phase contrast with through‐plane velocity encoding (2D‐PC) for pulse wave velocity (PWV) evaluation in the descending aorta using five different analysis techniques.Materials and Methods:Accuracy experiments were conducted on a tubular human‐tissue‐mimicking phantom integrated into a flow simulator. The theoretical PWV value was derived from the Moens‐Korteweg equation after measurement of the tube elastic modulus by uniaxial tensile testing (PWV = 6.6 ± 0.7 m/s). Repeatability was assessed on 20 healthy volunteers undergoing three consecutive MR examinations.Results:FVE M‐mode PWV was more repeatable than 2D‐PC PWV independently of the analysis technique used. The early systolic fit (ESF) method, followed by the maximum of the first derivative (1st der.) method, was the most accurate (PWV = 6.8 ± 0.4 m/s and PWV = 7.0 ± 0.6 m/s, respectively) and repeatable (inter‐scan within‐subject variation δ = 0.096 and δ = 0.107, respectively) for FVE M‐mode. For 2D‐PC, the 1st der. method performed best in terms of accuracy (PWV = 6.8 ± 1.1 m/s), whereas the ESF algorithm was the most repeatable (δ = 0.386).Conclusion:FVE M‐mode allows rapid, accurate and repeatable central PWV evaluation when the ESF algorithm is used. 2D‐PC requires long scan times and can provide accurate although much less repeatable PWV measurements when the 1st der. method is used. J. Magn. Reson. Imaging 2010;31:1185–1194. © 2010 Wiley‐Liss, Inc.
Quantitative 4D transcatheter intraarterial perfusion MRI for monitoring chemoembolization of hepatocellular carcinoma
Authors: Wang Dingxin , Jin Brian , Lewandowski Robert J. , Ryu Robert K. , Sato Kent T. , Mulcahy Mary F. , Kulik Laura M. , Miller Frank H. , Salem Riad , Li Debiao , Omary Reed A. , Larson Andrew C. 
Published: April 2010

AbstractPurpose:To develop a fully quantitative 4D transcatheter intraarterial perfusion (TRIP) magnetic resonance imaging (MRI) technique and prospectively test the hypothesis that quantitative 4D TRIP‐MRI can be used clinically to monitor intraprocedural liver tumor perfusion reductions during transcatheter arterial chemoembolization (TACE).Materials and Methods:TACE was performed within an x‐ray digital subtraction angiography (DSA)‐MRI procedure suite in 16 patients with hepatocellular carcinoma. Quantitative 4D TRIP‐MRI with targeted radiofrequency field mapping and dynamic longitudinal relaxation rate mapping was used to monitor changes in tumor perfusion during TACE. First‐pass perfusion analysis was performed to produce intraprocedural blood flow (Fρ) maps. Mean liver tumor perfusions before and after TACE were compared with a paired t‐test (α = 0.05).Results:Perfusion reductions were successfully measured with quantitative 4D TRIP‐MRI in 22 separate tumors during 18 treatment sessions. Mean tumor perfusion Fρ decreased from 16.3 (95% confidence interval [CI]: 10.7–21.9) before TACE to 5.0 (95% CI: 3.5–6.5) (mL/min/100 mL) after TACE. Tumor perfusion reductions were statistically significant (P < 0.0005), with a mean absolute perfusion change of 11.4 (95% CI: 5.6–17.1) (mL/min/100 mL) and a mean percentage reduction of 61.0% (95% CI: 48.3%–73.6%).Conclusion:Quantitative 4D TRIP‐MRI can be successfully performed within clinical interventional settings to monitor intraprocedural changes in liver tumor perfusion during TACE. J. Magn. Reson. Imaging 2010;31:1106–1116. © 2010 Wiley‐Liss, Inc.
Preoperative detection of prostate cancer: A comparison with 11C‐choline PET, 18F‐fluorodeoxyglucose PET and MR imaging
Authors: Watanabe Haruo , Kanematsu Masayuki , Kondo Hiroshi , Kako Nobuo , Yamamoto Naoki , Yamada Toru , Goshima Satoshi , Hoshi Hiroaki , Bae Kyongtae T. 
Published: April 2010

AbstractPurpose:To compare 11C‐choline positron emission tomography (C‐PET), 18F‐fluorodeoxyglucose PET (FDG‐PET), and MR imaging in the preoperative detection of prostate cancer.Materials and Methods:C‐PET, FDG‐PET, and MR images were obtained in 43 consecutive patients with suspected prostate cancer, and prostate cancers were histopathologically confirmed in 26 patients. Unenhanced T1‐weighted, T2‐weighted, and gadolinium‐enhanced MR images were obtained. C‐PET and FDG‐PET were conducted 1.5 and 60 minutes after injection of 5.5 and 5.0 MBq/kg tracers, respectively. A nuclear and a genitourinary radiologist retrospectively reviewed PET and MR images at random, respectively, and assigned a confidence level for the presence of prostate cancer using a four‐point scale. Diagnostic performance was tested using the McNemar test and receiver operating characteristic curve analysis.Results:The sensitivity was greater (P < 0.05) with MR (88%) and C‐PET (73%) images than with FDG‐PET images (31%). The accuracy was greater (P < 0.05) with MR images (88%) than with C‐PET (67%) and FDG‐PET (53%) images. The area‐under‐curve value with MR (0.90) was greater than those with C‐PET (0.53) and FDG‐PET (0.54) images (P < 0.01).Conclusion:MR imaging should be primarily performed in the preoperative detection of prostate cancer. C‐PET and FDG‐PET did not improve the detection. J. Magn. Reson. Imaging 2010;31:1151–1156. © 2010 Wiley‐Liss, Inc.
Repeatability of T1‐quantification in dGEMRIC for three different acquisition techniques: Two‐dimensional inversion recovery, three‐dimensional look locker, and three‐dimensional variable flip angle
Authors: Siversson Carl , Tiderius Carl‐Johan , Neuman Paul , Dahlberg Leif , Svensson Jonas 
Published: April 2010

AbstractPurpose:To evaluate the repeatability of the dGEMRIC (delayed gadolinium enhanced MRI of cartilage) method in osteoarthritis‐prone knee joints for three different T1 quantification techniques: two‐dimensional inversion recovery (2D‐IR), three‐dimensional Look‐Locker (3D‐LL), and three‐dimensional variable flip angle (3D‐VFA).Materials and Methods:Nine subjects were examined twice, with a 2‐week interval, using all three measurement techniques. Four regions of interest were defined in the central medial and lateral femoral cartilage. The repeatability was evaluated for each measurement technique. For the 3D techniques, the variation between different slices was also evaluated.Results:Repeatability expressed by root‐mean‐square coefficient of variation (CVRMS) showed similar results for 2D‐IR and 3D‐LL (5.4–8.4%). For 3D‐VFA CVRMS was higher (9.3–15.2%). Intraclass correlation coefficient showed both 2D‐IR and 3D‐LL reliability to be moderate, while 3D‐VFA reliability was low. Inter‐slice CVRMS and ICC was of the same magnitude as the repeatability. No clear differences could be interpreted between the condyles.Conclusion:Both 2D‐IR and 3D‐LL perform well in generating repeatable dGEMRIC results, while 3D‐VFA results are somewhat inferior. Furthermore, repeatability results in this study are similar to previously published results for healthy subjects. Finally, the positioning of the analyzed images is crucial to generate reliable repeatability results. J. Magn. Reson. Imaging 2010;31:1203–1209. © 2010 Wiley‐Liss, Inc.
Optimal fast T2‐weighted magnetic resonance microscopy imaging of the eye and its clinical application
Authors: Tanitame Keizo , Sasaki Ko , Sone Takashi , Otani Keiko 
Published: April 2010

AbstractPurpose:To compare a half‐Fourier single‐shot rapid acquisition with relaxation enhancement (RARE) sequence with a balanced steady‐state free precession (b‐SSFP) sequence in the evaluation of the eye using magnetic resonance (MR) microscopy imaging and to clarify the usefulness of RARE microscopy imaging in evaluating nonoperative glaucoma patients and patients who have undergone surgery for glaucoma or cataract.Materials and Methods:One‐mm and 2‐mm slice thickness images of RARE sequence and b‐SSFP sequence using a 1.5 T MR unit and a 23‐mm microscopy coil were obtained in eight healthy volunteers. The signal‐to‐noise (S/N) ratio of aqueous humor in the anterior chamber was measured quantitatively and visualization of the anterior chamber anatomy was assessed qualitatively. Furthermore, we evaluated 21 glaucoma patients (including six postoperative patients) and four patients after cataract surgery with 2‐mm slice thickness RARE MRI.Results:The 2‐mm slice thickness RARE imaging had a significantly greater S/N ratio than the 1‐mm slice thickness RARE imaging (P < 0.05) and acquired the best image quality among the four types of images (P < 0.01). Additionally, 2‐mm slice thickness RARE microscopy imaging could depict anterior chamber anatomy of glaucoma eyes and eyes after cataract surgery.Conclusion:We believe that optimal fast T2‐weighted MR microimaging might become a useful ophthalmologic examination technique. J. Magn. Reson. Imaging 2010;31:1210–1214. ©2010 Wiley‐Liss, Inc.
The Quaternary of the British Isles: factors forcing environmental change
Authors: Rose James 
Published: April 2010

AbstractThis paper considers the processes that have controlled cool temperate latitude terrestrial environments over the last ca 3 Ma, with particular reference to the British Isles. A scheme is proposed that is based on the processes that act on the land over any given period of time and are the product of climate modulated by rock type (the resisting agent) and relief (determined by tectonics and antecedent relief‐forming factors). Climate is generalised in terms of the range and rates of climate change determined by orbital forcing. During precession cycles climate change was small and insolation levels were forced by chemically and biologically driven processes. The period of obliquity cycles is characterised by patterns of climate change in which physical processes became effective and high‐magnitude fluvial and slope processes were reinforced by periglaciation and glaciation in susceptible regions. Eccentricity cycles include climate extremes of longer duration, and glaciation and periglaciation were the major contributors to landscape change, sediment transfer and sediment mixing. These climate‐forced processes produce distinctive landform, sediment and soil assemblages characteristic of particular episodes of Quaternary time. The lags between the successive systems are identified. Copyright © 2010 John Wiley & Sons, Ltd.
Extent and timing of the Last Glacial Maximum (LGM) in Britain and Ireland: a review
Authors: Chiverrell Richard C. , Thomas Geoffrey S. P. 
Published: April 2010

AbstractThe Last Glacial Maximum (LGM) of Marine Isotope Stage (MIS) 2 is defined here as the period either of maximum global ice volume or in which major ice sheets reached their maximum extent. Both definitions lack clarity as there is no reason to suppose that maximum volumes or limits were reached simultaneously at either all ice sheets or around the margins of individual ice sheets. Here we review the traditional terrestrial limits of the BIIS (British‐Irish Ice Sheet), examine developments in understanding the offshore record, and attempt a redefinition of the extent and timing of the MIS 2 maximum. As a working chronological model the build‐up of the BIIS is assigned to after 35–32 ka, the maximum to the period 27–21 ka and a more limited readvance after 19 ka. As marginal oscillations, driven by ice sheet dynamics, appear to have characterised much of the advance, and especially the retreat of the BIIS, caution should be exercised in assigning climatic significance to the many identified ice limits or still‐stands. While much of the terrestrial limit in Britain remains relatively unaltered, significant revision is required offshore around Britain and Ireland, to portray an extensive ice advance to the shelf edge and a period when the BIIS was conjoined with the adjacent Fenno‐Scandinavian Ice Sheet. Although there appears to be a broad synchrony between the BIIS and other major ice sheets, local controls have produced some variation in the timing of advance to and retreat from maximum limits for particular ice streams or lobes, but much of the offshore limit remains very poorly age constrained. Consequently, a key objective in future research should be to improve and refine the chronological control for all portions of the maximum margin of the BIIS and its subsequent retreat stages. Copyright © 2010 John Wiley & Sons, Ltd.
The Quaternary of the British Isles and adjoining seas
Authors: Rose James , Coxon Peter 
Published: April 2010

AbstractThis Special Issue of the Journal of Quaternary Science contains a set of 13 papers based on presentations at the Annual Discussion Meeting of the Quaternary Research Association held in London in January 2008. This Special Issue is concerned with four main themes: long‐term landscape signatures, river landscapes and responses to climate change, glacial landscapes and Lateglacial landscapes. The papers include substantial new data on the terrestrial and offshore Quaternary of the British Isles and provide a benchmark for aspects of current thinking on this topic. This volume is published in parallel with other special issues based on the 2008 QRA Discussion Meeting. These consist of The Quaternary Geology of the British Isles edited by David Bridgland and Nick Golledge in the Proceedings of the Geologists' Association and Climate variability of the British Isles and surrounding seas edited by Dan Charman and Danny McCarroll in Quaternary Science Reviews. Copyright © 2010 John Wiley & Sons, Ltd.
Rapid and delayed death of cultured trabecular meshwork cells after selective laser trabeculoplasty
Authors: Wood John P.M. , Plunkett Malcolm , Previn Victor , Chidlow Glyn , Casson Robert J. 
Published: April 2010

AbstractBackground and ObjectiveSelective laser trabeculoplasty (SLT) is becoming increasingly employed to reduce elevated intraocular pressure in glaucoma patients. SLT is known to target the ocular trabecular meshwork (TM), but the exact response mechanisms to this treatment have not been clearly delineated. The aim of the present study, therefore, was to investigate the modes of death of cultured bovine TM cells subjected to SLT in vitro.Materials and MethodsBovine TM cell cultures were established, pigmented with exogenous melanin and irradiated with a Q‐switched, frequency doubled, Nd:YAG laser, at different energy settings (0.05–1.0 mJ). Influences on cells were determined for up to 10 days post‐treatment by trypan blue exclusion, terminal deoxynucleotidyl transferase dUTP nick‐end labeling (TUNEL) and by morphological assessment. Furthermore, homogeneous mixtures of pigmented and non‐pigmented TM cells were irradiated to ascertain selectivity of laser effects.ResultsAt higher energy levels (1.0, 0.75 mJ), immediate loss of cells was detected at the irradiated site. Trypan blue exclusion analysis showed that necrotic cell death subsequently occurred up to 8 hours following irradiation, peaking at 60 minutes. This was followed by delayed cell death peripheral to the irradiated area which was characteristic of apoptosis and which peaked at 2–3 days post‐treatment. When mixed cultures were tested, laser treatment selectively killed pigmented cells at an energy level equivalent to the lower cell killing threshold in the initial studies (0.2 mJ) but at the higher laser energy of 0.35 mJ, all cells were non‐selectively killed.ConclusionsSLT treatment killed pigmented TM cells in culture by a variety of processes (instant vaporization, rapid necrosis, delayed apoptosis), depending on the magnitude of the energy used and the distance from the center of the irradiated zone. These data may assist in the elucidation of the mechanism of action of the SLT procedure on TM cells in situ. Lasers Surg. Med. 42:326–337, 2010. © 2010 Wiley‐Liss, Inc.
Diffuse reflectance spectroscopy for optical soft tissue differentiation as remote feedback control for tissue‐specific laser surgery
Authors: Stelzle Florian , Tangermann‐Gerk Katja , Adler Werner , Zam Azhar , Schmidt Michael , Douplik Alexandre , Nkenke Emeka 
Published: April 2010

AbstractBackground and ObjectiveLaser surgery does not provide haptic feedback for operating layer‐by‐layer and thereby preserving vulnerable anatomical structures like nerve tissue or blood vessels. Diffuse reflectance spectra can facilitate remote optical tissue differentiation. It is the aim of the study to use this technique on soft tissue samples, to set a technological basis for a remote optical feedback system for tissue‐specific laser surgery.Materials and MethodsDiffuse reflectance spectra (wavelength range: 350–650 nm) of ex vivo types of soft tissue (a total of 10,800 spectra) of the midfacial region of domestic pigs were remotely measured under reduced environmental light conditions and analyzed in order to differentiate between skin, mucosa, muscle, subcutaneous fat, and nerve tissue. We performed a principal components (PC) analysis (PCA) to reduce the number of variables. Linear discriminant analysis (LDA) was utilized for classification. For the tissue differentiation, we calculated the specificity and sensitivity by receiver operating characteristic (ROC) analysis and the area under curve (AUC).ResultsSix PCs were found to be adequate for tissue differentiation with diffuse reflectance spectra using LDA. All of the types of soft tissue could be differentiated with high specificity and sensitivity. Only the tissue pairs nervous tissue/fatty tissue and nervous tissue/mucosa showed a decline of differentiation due to bio‐structural similarity. However, both of these tissue pairs could still be differentiated with a specificity and sensitivity of more than 90%.ConclusionsAnalyzing diffuse reflectance spectroscopy with PCA and LDA allows for remote differentiation of biological tissue. Considering the limitations of the ex vivo conditions, the obtained results are promising and set a basis for the further development of a feedback system for tissue‐specific laser surgery. Lasers Surg. Med. 42:319–325, 2010. © 2010 Wiley‐Liss, Inc.
Protective effect of autophagy in laser‐induced glioma cell death in vitro
Authors: Krmpot Aleksandar J. , Janjetovic Kristina D. , Misirkic Maja S. , Vucicevic Ljubica M. , Pantelic Dejan V. , Vasiljevic Darko M. , Popadic Dusan M. , Jelenkovic Branislav M. , Trajkovic Vladimir S. 
Published: April 2010

AbstractBackground and ObjectiveLaser phototherapy could be potentially used for cancer treatment, but the mechanisms of laser‐induced cell death are not completely understood. Autophagy is the process in which the damaged cellular proteins and organelles are engulfed by and destroyed in acidified multiple‐membrane vesicles. The aim of the present study was to investigate the role of autophagy in laser‐induced tumor cell death in vitro.Study Design/Materials and MethodsThe monolayers of U251 human glioma tumor cells were exposed to 532 nm laser light from a single mode frequency‐doubled Nd‐YVO4 laser. A flattened Gaussian radial profile of laser beam (0.5–4 W) was used to uniformly illuminate entire colony of cells for various amounts of time (15–120 seconds) in the absence of cell culture medium. The cells were grown for 24 hours and the cell viability was determined by crystal violet or MTT assay. The presence of autophagy was assessed after 16 hours by fluorescence microscopy/flow cytometric analysis of acridine orange‐stained autophagolysosomes and Western blot analysis of the autophagosome‐associated LC3‐II protein. The concentration of the principal pro‐autophagic protein beclin‐1 was determined after 6 hours by cell‐based ELISA.ResultsThe intracytoplasmic accumulation of autophagic vesicles, increase in LC3‐II and up‐regulation of beclin‐1 expression were clearly observed under irradiation conditions that caused approximately 50% cytotoxicity. Post‐irradiation addition of three different autophagy inhibitors (bafilomycin A1, chloroquine, or wortmannin) further increased the laser‐induced cytotoxicity, without affecting non‐irradiated cells.ConclusionsThese data indicate that beclin‐1‐dependent induction of autophagy can protect glioma cells from laser‐mediated cytotoxicity. Lasers Surg. Med. 42:338–347, 2010. © 2010 Wiley‐Liss, Inc.
Assessment of the return period of near‐PMP point and catchment rainfall for England and Wales
Authors: Collier Chris G. , Morris David G. , Jones David A. 
Published: April 2010

AbstractThe return periods of sub‐daily rainfall events approaching Probable Maximum Precipitation (PMP) have been estimated for point locations and catchment areas using the assumptions made in a previously published storm model. It has been assumed that PMP of around 12 h duration is the result of severe thunderstorms for catchments up to about 200 km2and of mesoscale convective systems (MCSs) for larger catchments. The analysis suggests return periods ranging from around 1 in 10 000 years for point locations to 1 in 500 000 years for large catchments, though these are very dependent on the assumptions. The results are compared with estimates from a number of other sources. Copyright © 2010 Royal Meteorological Society