bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of measurements of the transverse diameter and perimeter of the fetal thymus obtained by magnetic resonance and ultrasound imaging
Authors: De Leon‐Luis Juan , Ruiz Yolanda , Gamez Francisco , Pintado Pilar , Oyelese Yinka , Pereda Ana , Ortiz‐Quintana Luis , Santolaya‐Forgas Joaquin 
Published: April 2011

AbstractPurpose:To compare measurements of the fetal thymus obtained by magnetic resonance imaging (MRI) and ultrasound (US).Materials and Methods:Written informed consent was obtained from the patients that participated in this Institutional Review Board‐approved observational study. The study population consisted of 17 pregnant women carrying fetuses between 21 and 34 weeks of gestation with suspected abnormalities. The transverse diameter and perimeter of the thymus were measured in these fetuses at the level of an axial view of the thorax that includes the pulmonary, aorta, and superior vena cava. The degree of agreement between MRI and US measurements was determined using Lin's concordance correlation coefficient and Bland–Altman analysis.Results:The mean (standard deviation, SD) gestational age at the time of the prenatal evaluation was 28.4 weeks (3.6). The thymus was measured by MRI and US in all cases. Comparison of the measurements from these two imaging modalities demonstrated a relatively good reproducibility with no evidence of systematic error.Conclusion:MRI and US measurements of the fetal thymus during the second half of pregnancy are comparable. This finding suggests that MRI can become a useful adjuvant to US for assessment of the fetal thymus. J. Magn. Reson. Imaging 2011;33:1100–1105. © 2011 Wiley‐Liss, Inc.
Comparison of the incidence of pancreatic abnormalities between high risk and control patients: Prospective pilot study with 3 tesla MR imaging
Authors: Shin Sang Soo , Armao Diane M. , Burke Lauren M.B. , Kim Hong Jin , Skrzynia Cecile , Otey Carol A. , Semelka Richard C. 
Published: April 2011

AbstractPurpose:To compare the incidence of pancreatic abnormalities detected by MR imaging between high‐risk patients and control patients.Materials and Methods:Forty‐one consecutive patients who had two or more first‐degree relatives with pancreatic cancer and who were asymptomatic with no clinical evidence of pancreatic cancer were prospectively included in this study. A control group was obtained by reviewing consecutive patients undergoing 3Tesla (T) MRI examinations for nonpancreatic indications. On MR imaging, the presence of pancreatic abnormalities were evaluated in consensus by two radiologists who were blinded to clinical history. Pancreatic abnormalities were categorized as developmental abnormalities, mass‐type lesions, inflammatory disease, and others.Results:Overall, the incidence of pancreatic abnormalities was greater in the high‐risk group than in the control group, but not statistically significant (P = 0.244). In the high‐risk group, a total of 16 patients (39%) were diagnosed with pancreatic abnormalities, whereas in the control group, 11 patients (25%) were diagnosed with pancreatic abnormalities. Regarding mass‐type lesions, there was a significant difference in incidence between the high‐risk group, with a total of seven patients (17%), and the control group, with one patient (2%) (P = 0.028). There were no cases of imaging diagnosis of pancreatic cancer or tissue evaluation by surgical pathology in either group.Conclusion:Our prospective pilot study demonstrated a higher incidence of mass‐type lesions in patients at increased risk for pancreatic cancer. J. Magn. Reson. Imaging 2011;33:1080–1085. © 2011 Wiley‐Liss, Inc.
Comparison of intravascular and extracellular contrast media for absolute quantification of myocardial rest‐perfusion using high‐resolution MRI
Authors: Ritter Christian O. , Wilke Aline , Wichmann Tobias , Beer Meinrad , Hahn Dietbert , Köstler Herbert 
Published: April 2011

AbstractPurpose:To use the contrast agent gadofosveset for absolute quantification of myocardial perfusion and compare it with gadobenate dimeglumine (Gd‐BOPTA) using a high‐resolution generalized autocalibrating partially parallel acquisition (GRAPPA) sequence.Materials and Methods:Ten healthy volunteers were examined twice at two different dates with a first‐pass perfusion examination at rest using prebolus technique. We used a 1.5 T scanner and a 32 channel heart‐array coil with a steady‐state free precession (SSFP) true fast imaging with steady state precession (trueFISP) GRAPPA sequence (acceleration‐factor 3). Manual delineation of the myocardial contours was performed and absolute quantification was performed after baseline and contamination correction. At the first appointment, 1cc/4cc of the extracellular contrast agent Gd‐BOPTA were administered, on the second date, 1cc/4cc of the blood pool contrast agent (CA) gadofosveset. At each date the examination was repeated after a 15‐minute time interval.Results:Using gadofosveset perfusion the value (in cc/g/min) at rest was 0.66 ± 0.25 (mean ± standard deviation) for the first, and 0.55 ± 0.24 for the second CA application; for Gd‐BOPTA it was 0.62 ± 0.25 and 0.45 ± 0.23. No significant difference was found between the acquired perfusion values. The apparent mean residence time in the myocardium was 23 seconds for gadofosveset and 19.5 seconds for Gd‐BOPTA. Neither signal‐to‐noise ratio (SNR) nor subjectively rated image contrast showed a significant difference.Conclusion:The application of gadofosveset for an absolute quantification of myocardial perfusion is possible. Yet the acquired perfusion values show no significant differences to those determined with Gd‐BOPTA, maintained the same SNR and comparable perfusion values, and did not picture the expected concentration time‐course for an intravasal CA in the first pass. J. Magn. Reson. Imaging 2011;33:1047–1051. © 2011 Wiley‐Liss, Inc.
Accelerated noncontrast‐enhanced pulmonary vein MRA with distributed compressed sensing
Authors: Akçakaya Mehmet , Hu Peng , Chuang Michael L. , Hauser Thomas H. , Ngo Long H. , Manning Warren J. , Tarokh Vahid , Nezafat Reza 
Published: April 2011

AbstractPurpose:To investigate the efficacy of distributed compressed sensing (CS) to accelerate free‐breathing, electrocardiogram (ECG)‐triggered noncontrast pulmonary vein (PV) magnetic resonance angiography (MRA).Materials and Methods:Fully sampled ECG‐triggered noncontrast PV MRA, using a spatially selective slab inversion preparation sequence, was acquired on seven healthy adult subjects (27 ± 17 years, range: 19–65 years, 4 women). The k‐space data were retrospectively randomly undersampled by factors of 2, 4, 6, 8, and 10 and then reconstructed using distributed CS and coil‐by‐coil CS methods. The reconstructed images were evaluated by two blinded readers in consensus for assessment of major PV branches as well as the presence of artifacts in left atrium (LA) and elsewhere. Diameters of right inferior and right superior PV branches were measured. Additionally, mean square errors (MSE) of the reconstructions were calculated.Results:Both CS methods resulted in image quality scores similar to the fully sampled reference images at undersampling factors up to 6‐fold for distributed CS and 4‐fold for coil‐by‐coil CS reconstructions. There was no difference in the presence of artifacts in LA and freedom from important artifacts elsewhere between the two techniques up to undersampling factors of 10 compared to the fully sampled reconstruction. For the PV diameters, no systematic variation between the reference and the reconstructions were observed for either technique. There were no significant differences in MSE between the two methods when compared at a given rate, but the difference was significant when compared across all rates.Conclusion:The sparsity of noncontrast PV MRA and the joint sparsity of different coil images allow imaging at high undersampling factors (up to 6‐fold) when distributed CS is used. J. Magn. Reson. Imaging 2011;33:1248–1255. © 2011 Wiley‐Liss, Inc.
Endorectal MRI after radiation therapy: Questioning the sextant analysis
Authors: Kumbhani Shilpa R. , Coakley Fergus V. , McCulloch Charles E. , Wang Z. Jane , Kurhanewicz John , Roach Mack , Westphalen Antonio C. 
Published: April 2011

AbstractPurpose:To evaluate whether the information gained by three coregistration systems (sextant, hemi‐prostate, and whole gland) differs significantly, suggesting that one approach should be routinely favored over the others. Despite its known limitations, sextant is the generally accepted standard for magnetic resonance imaging (MRI) and biopsy coregistration; nevertheless, depending on the magnitude of localization errors, other options may be adequate.Materials and Methods:Institutional Review Board approval was obtained and the study was Health Insurance Portability and Accountability Act (HIPAA)‐compliant. We identified 70 patients who underwent 1.5 T endorectal MRI of the prostate between 1999 and 2008 after external beam radiotherapy for prostate cancer. A single reader reviewed all T2‐weighted images for the presence or absence of tumor. The performance of each approach was quantified using receiver operating characteristic (ROC) curve analysis. Transrectal ultrasound‐guided sextant biopsies were used as a standard of reference.Results:The areas under the ROC curve indicating accuracy for each MRI approach were 0.63 (sextant), 0.68 (hemi‐prostate), and 0.71 (whole gland). There was no statistically significant difference among these approaches.Conclusion:As expected, the point estimate was higher for the whole‐gland approach, but not significantly. Reliable assessment of locally recurrent prostate cancer after external beam radiotherapy by endorectal MRI may be made using a sextant, hemi‐prostate, or whole gland approach. The option for one or another approach should not be solely based on estimations of imaging accuracy, but on the purpose of the procedure. J. Magn. Reson. Imaging 2011;33:1086–1090. © 2011 Wiley‐Liss, Inc.
Motion correction in diffusion‐weighted MRI of the breast at 3T
Authors: Arlinghaus Lori R. , Welch E. Brian , Chakravarthy A. Bapsi , Xu Lei , Farley Jaime S. , Abramson Vandana G. , Grau Ana M. , Kelley Mark C. , Mayer Ingrid A. , Means‐Powell Julie A. , Meszoely Ingrid M. , Gore John C. , Yankeelov Thomas E. 
Published: April 2011

AbstractPurpose:To provide a quantitative assessment of motion and distortion correction of diffusion‐weighted images (DWIs) of the breast and to evaluate the effects of registration on the mean apparent diffusion coefficient (mADC).Materials and Methods:Eight datasets from four patients with breast cancer and eight datasets from six healthy controls were acquired on a 3T scanner. A 3D affine registration was used to align each set of images and principal component analysis was used to assess the results. Variance in tumor ADC measurements, tumor mADC values, and voxel‐wise tumor mADC values were compared before and after registration for each patient.Results:Image registration significantly (P = 0.008) improved image alignment for both groups and significantly (P < 0.001) reduced the variance across individual tumor ADC measurements. While misalignment led to potential under‐ and overestimation of mADC values for individual voxels, average tumor mADC values did not significantly change (P > 0.09) after registration.Conclusion:3D affine registration improved the alignment of DWIs of the breast and reduced the variance between ADC measurements. Although the reduced variance did not significantly change tumor region‐of‐interest measures of mADC, it may have a significant impact on voxel‐based analyses. J. Magn. Reson. Imaging 2011;33:1063–1070. © 2011 Wiley‐Liss, Inc.
Phosphorylation status of heat shock protein 27 influences neurite growth in adult dorsal root ganglion sensory neurons in vitro
Authors: Williams Kristy L. , Mearow Karen M. 
Published: April 2011

AbstractThe small heat shock protein Hsp27 influences neurite growth, potentially via phosphorylation‐dependent interactions of Hsp27 with actin. To investigate the contribution of Hsp27 phosphorylation to neurite growth in adult DRG neurons, we employed hamster Hsp27 cDNA constructs (in pIRES‐EGFP) with mutations in the phosphorylation sites, either mimicking constitutively phosphorylated Hsp27 (with substitution of serines 15 and/or 90 by glutamate) or preventing phosphorylation at the site (serines 15/90 replaced by alanine). Five mutant constructs were employed in this study in addition to wild‐type hamster Hsp27; siRNA directed against the rat Hsp27 was used to depress endogenous Hsp27. Neurite growth was assessed in EGFP‐expressing cells following immunocytochemistry and tracing of neurite growth. Hsp27 staining and phalloidin labelling were used to examine Hsp27 and actin colocalization in neurons and growth cones. Overall, our results demonstrate that the role that Hsp27 plays in neurite growth can be affected by phosphorylation, oligomerization, or a combination of both. Hsp27 constructs that are able to dimerize and/or form large oligomers [WT, Hsp27‐AA, Hsp27‐AE, Hsp27−Δ(5–23)] rescued siRNA‐depressed neurite growth, whereas Hsp27 mutants that do not form dimers or oligomers (Hsp27‐EE and Hsp27‐EA) were unable to rescue the effect of the siRNA. The phalloidin labelling qualitatively showed a higher level of localization of actin with the Hsp27‐AA compared with the other constructs. Although phosphorylation appears to be important in growth, the ability of Hsp27 to exist in both phospho‐ and nonphospho‐ states is likely key to its role in regulating cytoskeletal elements involved in neurite growth. © 2011 Wiley‐Liss, Inc.
Optimizing the location of weather monitoring stations using estimation uncertainty
Authors: Amorim Ana M. T. , Gonçalves Alexandre B. , Nunes Luís Miguel , Sousa António Jorge 
Published: April 2011

AbstractIn this article, we address the problem of planning a network of weather monitoring stations observing average air temperature (AAT). Assuming the network planning scenario as a location problem, an optimization model and an operative methodology are proposed. The model uses the geostatistical uncertainty of estimation and the indicator formalism to consider in the location process a variable demand surface, depending on the spatial arrangement of the stations. This surface is also used to express a spatial representativeness value for each element in the network. It is then possible to locate such a network using optimization techniques, such as the used methods of simulated annealing (SA) and construction heuristics. This new approach was applied in the optimization of the Portuguese network of weather stations monitoring the AAT variable. In this case study, scenarios of reduction in the number of stations were generated and analysed: the uncertainty of estimation was computed, interpreted and applied to model the varying demand surface that is used in the optimization process. Along with the determination of spatial representativeness value of individual stations, SA was used to detect redundancies on the existing network and establish the base for its expansion. Using a greedy algorithm, a new network for monitoring average temperature in the selected study area is proposed and its effectiveness is compared with the current distribution of stations. For this proposed network distribution maps of the uncertainty of estimation and the temperature distribution were created. Copyright © 2011 Royal Meteorological Society
Effects of cuvette surface material on ammonia‐, nitrous oxide‐, carbon dioxide‐, and methane‐concentration measurements
Authors: Predotova Martina , Kretschmann Roland , Gebauer Jens , Buerkert Andreas 
Published: April 2011

AbstractClosed‐chamber systems are commonly used to determine gaseous C and N emissions from agricultural soils. We investigated the effects of eight cuvette surfaces on two standard gas concentrations of NH3, N2O, CO2, and CH4 under laboratory conditions. Cuvette surface materials differentially affected gas adhesion or recovery as a function of the type and the concentration of the gases. Given the strong effects on results of gas measurements in closed‐chamber systems, both the type and the concentration of the measured gases need to be considered in selecting cuvette surface materials.
Morbidity, mortality, and pathological response in patients with gastric cancer preoperatively treated with chemotherapy or chemoradiotherapy
Authors: Valenti V. , Hernandez‐Lizoaín J.L. , Beorlegui M.C. , Diaz‐Gozalez J.A. , Regueira F.M. , Rodriguez J.J. , Viudez A. , Sola I. , Cienfuegos J.A. 
Published: April 2011

AbstractBackgroundSignificant tumor downstaging has been achieved in patients with localized gastric adenocarcinoma by preoperative chemoradiotherapy (ChRT) or induction chemotherapy (Ch). However the influence of ChRT and Ch on postoperative outcomes has not yet been clarified, with very few studies examining this issue. We retrospectively analyzed the efficacy in terms of pathological response and early postoperative complications of two protocols of preoperative ChRT and Ch for locally advanced gastric cancer.MethodsBetween 2000 and 2008, 72 patients with operable locally advanced gastric cancer (cT3‐4/N+) were treated with preoperative treatment: 1—patients receiving induction Ch or 2—neoadjuvant Ch followed by concurrent ChRT. Postoperative histopathological regression and surgical complications were investigated including variables related to patients, surgical variables, preoperative treatment, and tumor.ResultsThere were no differences in the incidence of complications between the ChRT and Ch groups (30.9% vs. 33.3%). The most frequent complications were nonspecific surgical complications (pneumonia [12.5%] and infection from intravenous catheters [9.7%]). Risk factors for complications were high‐body mass index (BMI > 25 kg/m2) and extension of surgery to the pancreas and spleen. A major pathological response was observed in 33.3% of patients, being more frequent in the ChRT group (47.6% vs. 13.3%; χ2, P = 0.0024).ConclusionsPreoperative treatment with Ch or ChRT for locally advanced gastric cancer can be performed safely with an acceptable operative morbidity and low operative mortality rate with careful consideration of the added risk associated with BMI and surgical resection of the pancreas and spleen. Ch and ChRT is feasible and effective in terms of pathological response and R0 resection. J. Surg. Oncol. 2011;104:124–129. © 2011 Wiley‐Liss, Inc.
Covalent Growth Factor Immobilization Strategies for Tissue Repair and Regeneration
Authors: Masters Kristyn S. 
Published: April 2011

AbstractGrowth factors play a critical role in regulating processes involved in cellular differentiation and tissue regeneration, and are therefore considered essential elements in many tissue engineering strategies. The covalent immobilization of growth factors to biomaterial matrices addresses many of the challenges associated with delivering freely‐diffusible growth factors and has thus emerged as a promising method of achieving localized and sustained growth factor delivery. This Feature Article discusses methods that have been used to immobilize growth factors to substrates, followed by an overview of several tissue repair and regeneration applications in which immobilized growth factors have been used. magnified image
Towards the Sustainable Production of Higher‐Molecular‐Weight Polyglycerol
Authors: Salehpour Somaieh , Dubé Marc A. 
Published: April 2011

AbstractThe step‐growth polymerization of glycerol to relatively high molecular weight polyglycerol is investigated. Glycerol is a renewable material that can be derived from the transesterification of vegetable oils to biodiesel. Several soluble catalysts and their reaction mechanisms are compared and their effect on polymer molecular weight and microstructure is measured. High‐molecular‐weight PG with multimodal molecular weight distributions is observed using GPC, and partial branching is identified using 13C NMR spectroscopy. Theoretical models are used to predict the gel point and to calculate monomer functionality. magnified image
Dose escalation of intravenous irinotecan using oral cefpodoxime: A phase I study in pediatric patients with refractory solid tumors
Authors: McGregor Lisa M. , Stewart Clinton F. , Crews Kristine R. , Tagen Michael , Wozniak Amy , Wu Jianrong , McCarville M. Beth , Navid Fariba , Santana Victor M. , Houghton Peter J. , Furman Wayne L. , Rodriguez‐Galindo Carlos 
Published: April 2011

AbstractBackgroundAdministration of an oral cephalosporin allowed advancement of the dosage of oral irinotecan. This study investigates whether administration of an oral cephalosporin increases the maximum tolerated dose (MTD) of intravenous irinotecan.ProcedureIrinotecan was administered intravenously on Days 1–5 and Days 8–12 of a 21‐day cycle with continuous oral cefpodoxime starting 2 days prior to irinotecan. Cohorts of 3–6 pediatric patients with refractory solid tumors were enrolled at 4 dosage levels, starting at the single‐agent irinotecan MTD of 20 mg/m2/dose.ResultsThe 17 evaluable patients received 39 courses of therapy. None of the patients treated with 20 mg/m2/dose experienced dose‐limiting toxicity (DLT). One of six patients treated at 30 mg/m2/dose experienced dose‐limiting neutropenia. Two of three patients treated with 45 mg/m2/dose and two of five treated with 40 mg/m2/dose experienced dose‐limiting diarrhea, with associated dehydration and anorexia. Two unconfirmed partial responses were observed after one course in a patient with Ewing sarcoma and one with paraganglioma. A child with refractory neuroblastoma had disease stabilization through 12 courses of therapy. Median (range) systemic exposure to SN‐38 at the MTD (30 mg/m2/dose) was 67 ng‐h/mL (36 to 111 ng‐h/mL).ConclusionsThe MTD of intravenous irinotecan administered on a protracted schedule was increased by 50% from 20 to 30 mg/m2/dose with the addition of oral cefpodoxime. The most prominent DLT remained diarrhea. High interpatient variability in irinotecan pharmacokinetics was observed; however, SN‐38 exposure at the MTD was greater than most reported exposures with the 20 mg/m2 dosage. Pediatr Blood Cancer 2012; 58: 372–379. © 2011 Wiley Periodicals, Inc.
Time‐to‐antibiotic administration as a quality of care measure in children with febrile neutropenia: A survey of pediatric oncology centers
Authors: McCavit Timothy L. , Winick Naomi 
Published: April 2011

AbstractTime‐to‐antibiotic administration (TTA) has been suggested as a quality‐of‐care (QOC) measure for pediatric oncology patients with febrile neutropenia (FN). Unknown, however, is to what extent pediatric oncology centers utilize TTA. Therefore, we designed and administered an electronic survey (68% response rate) of programs in the Children's Oncology Group to assess TTA utilization. Nearly half of respondents track TTA. Most reported using a benchmark of less than 60 min from arrival. TTA is a commonly used QOC measure for pediatric FN despite an absence of studies establishing its validity and a lack of data supporting its impact on outcomes of FN. Pediatr Blood Cancer 2012; 58: 303–305. © 2011 Wiley Periodicals, Inc.