bluuebunny/crossref_metadata_2025_split huggingface dataset:
1H magnetic cross‐relaxation between multiple solvent components and rotationally immobilized protein
Authors: Hinton Denise P. , Bryant Robert G. 
Published: February 2011

AbstractMagnetic cross‐relaxation spectra or Z‐spectra are presented for water, acetone, methanol, dimethylsulfoxide, and acetonitrile in cross‐linked bovine serum albumin gels. Each solvent studied, reports the same Z‐spectrum linewidth and shape for the solid component that follows from solutions of the coupled relaxation equations. The Z‐spectra demonstrate competition among solvents for specific protein binding sites. The rate of magnetization transfer in the rotationally immobilized protein environment is approximated by 1/T2 for the solid component, which is shown to account for the observed magnetization transfer rates in the systems studied. The temperature dependence of the Z‐spectra are different for water compared with the organic solvents. The cross‐relaxation efficiency in the organic solvents decreases with increasing temperature because molecules bind less well at high temperature. For water, the hydrogen exchange path becomes increasingly important relative to the whole molecule path with increasing temperature, which improves the net cross‐relaxation efficiency.
Coherence transfer by isotropic mixing in carr‐purcell‐meiboom‐gill imaging: Implications for the bright fat phenomenon in fast spin‐echo imaging
Authors: Williamson Daniel S. , Mulkern Robert V. , Jakab Peter D. , Jolesz Ferenc A. 
Published: February 2011

AbstractIt is well known that when compared to conventional spin‐echo (CSE) imaging for equivalent effective echo times, fast spin‐echo (FSE) imaging experiments yield higher signal intensities for coupled spin systems, such as that for lipid. One hypothesis put forth for this phenomenon is the removal of scalar coupling‐based echo amplitude modulation by the FSE ψ pulse train. This would result in the maintenance of signal intensity in the late echoes, with an overall increase in image signal when the multiecho train data is combined to form the image data. It will be shown that in images and spectra obtained from the final echo of a Carr‐Purcell‐Meiboom‐Gill (CPMG) ψ pulse train, an increase in signal in coupled spin systems occurs, when compared to conventional single‐echo images and spectra at identical echo times. One‐ and two‐dimensional spectroscopy experiments confirm that it is the generation of an isotropic mixing Hamiltonian by the ψ pulse train in FSE that is responsible for the increased signal in images of a simple AX system and of corn oil, a model for human fat. This relative increase in signal is due to the maintenance of in‐phase magnetization in the coupled spin systems by this Hamiltonian. In CSE, the weak coupling Hamiltonian allows development of antiphase coherences which, in the presence of the line broadening due to the imaging gradients, result in signal loss.
Quantitative magnetic resonance imaging of perfusion using magnetic labeling of water proton spins within the detection slice
Authors: Schwarzbauer Christian , Morrissey Sean P. , Haase Axel 
Published: February 2011

AbstractA technique for noninvasive quantitative magnetic resonance imaging of perfusion is presented. It relies on using endogenous water as a freely diffusible tracer. Tissue water proton spins are magnetically labeled by slice‐selective inversion, and longitudinal relaxation within the slice is detected using a fast gradient echo magnetic resonance imaging technique. Due to blood flow, nonexcited spins are washed into the slice resulting in an acceleration of the longitudinal relaxation process. Incorporating this phenomenon into the Bloch equation yields an expression that allows quantification of perfusion on the basis of a slice‐selective and a nonselective inversion recovery experiment. Based on this technique, quantitative parameter maps of the regional cerebral blood flow (rCBF) were obtained from eight rats. Evaluation of regions of interest within the cerebral hemispheres yielded an average rCBF value of 104 ± 21 ml/min/100 g, which increased to 219 ± 30 ml/min/100 g during hypercapnia. The measured rCBF values are in good agreement with previously reported literature values.
Rapid repetition of the “burst” sequence: The role of diffusion and consequences for imaging
Authors: Doran Simon J. , Jakob Peter , Décorps Michel 
Published: February 2011

AbstractWhen the Burst pulse sequence (Hennig ef al. MAGMA 1, 39–48 (1993)) is applied with elementary pulses of finite flip angle, a non‐uniform longitudinal magnetization is created, in the form of a series of fine bands of saturated spins. Both during and after the pulse train, the molecules contained within these bands diffuse. In this paper a full description is given of the evolution of the non‐uniform longitudinal magnetization subsequent to the pulse train and the theory is verified experimentally. The value of the diffusion coefficient influences strongly the signal obtained when the Burst sequence is repeated rapidly. The consequences of this for imaging are discussed and, in particular, for the so‐called “frequency‐shifted” Burst technique.
Implementation of a fast gradient‐echo SVD encoding technique for dynamic imaging
Authors: Panych Lawrence P. , Oesterle Claudia , Zientara Gary P. , Hennig Jürgen 
Published: February 2011

AbstractIn the paper, the results of a fast gradient‐echo implementation of the singular value decomposition (SVD) encoding technique for dynamic imaging are presented. The method used is an adaptation with several critical modifications of a keyhole‐type approach previously proposed but not implemented. The method was tested by imaging the events following injection of a contrast agent into a phantom, producing a series of dynamic image updates. It is demonstrated that, for this type of application, the SVD encoding technique adequately follows dynamic changes with even a small number of encodes. The result is comared qualitatively to that obtained by standard Fourier‐based keyhole imaging and is shown to provide improved spatial resolution of dynamic events when updating with the same number of encodes.
Phase‐Modulated binomial RF pulses for fast spectrally‐selective musculoskeletal imaging
Authors: Thomasson David , Purdy David , Finn J. Paul 
Published: February 2011

AbstractTwo fat‐suppressed three‐dimensional gradient echo pulse sequences, FLASH and DESS (Double Echo in Steady‐State), that have significantly reduced scan time compared with conventional chemical shift fat‐suppression sequences are presented. This fat‐suppression technique is based on selectively exciting water spins using a time‐optimized binomial RF pulse pair at the water resonance frequency with a null in the excitation profile at the fat frequency. To minimize the total pulse length, the delay between the binomial components of the RF pulse is decreased from a standard jump‐return implementation. To maintain the proper null frequency, the phase of the second RF pulse is shifted such that it returns the fat resonance back to its initial z position while further tipping the water spins. Nonselective phase‐modulated RF pulse pairs can be implemented in 1.20 ms at 1.0 T, significantly reducing the minimum TR.
Calculation of the magnetization distribution for fluid flow in curved vessels
Authors: Jou Liang‐Der , van Tyen Rem , Berger Stanley A. , Saloner David 
Published: February 2011

AbstractThe signal Intensity in magnetic resonance angiography (MRA) images reflects both morphological and flow‐related features of vascular anatomy. A thorough understanding of MRA, therefore, demands a careful analysis of flow‐related effects. Computational fluid dynamics (CFD) methods are very powerful in determining flow patterns in 3D tortuous vessels for both steady and unsteady flow. Previous simulations of MRA images calculated the magnetization of flowing blood by tracking particles as they moved along flow streamlines that had been determined by a CFD calculation. This manuscript describes MRA simulations that use CFD calculations to determine magnetization variation at a fixed point and, therefore, do not require streamline tracking to calculate the distribution of magnetization in flowing fluids. This method inherently accounts for uniform particle density, avoids problems associated with tracking particles close to the wall, and is well‐suited to modeling pulsatile flow.
The effect of magnetization transfer in meniscal fibrocartilage
Authors: Adler Ronald S. , Swanson Scott D. , Doi Kei , Craig Joseph G. , Aisen Alex M. 
Published: February 2011

AbstractMagnetic resonance imaging of the knee was performed in 28 patients (ages 15–72 years), using a 1.5‐T unit. Volume gradient echo (3D GRASS) acquisition with and without presaturation off‐resonance RF pulse was used to evaluate magnetization transfer (MT) effects, determined by placing regions of Interest on muscle, fat, hyaline, and fibrocartilage; the percent change in signal intensity was calculated and compared using a paired two‐sample t test. An in vitro study of the normal meniscus from a cadaver containing a scalpel cut extending to an articular surface was performed to observe the relative improvement in contrast in the presence of a small meniscal defect. MR imaging of the specimen was performed using an Omega CSI 2.0–T system (General Electric Medical Systems, Fremont, CA). Analysis of clinical images resulted in signal loss, compared to that of the identically timed and tuned non‐MT images of 47 ± 5, 8 ± 5, 49 ± 5, and 57 ± 7% for muscle, fat, articular cartilage and fibrocartilage, respectively. Application of MT improved the depiction of the artificially introduced meniscal defect. Meniscal fibrocartilage demonstrates significant MT effect after application of off‐resonance RF presaturation, which may improve visualization of meniscal defects.
Temporal resolution improvement in dynamic imaging
Authors: Fredrickson Jill O. , Pelc Norbert J. 
Published: February 2011

AbstractIn some dynamic imaging applications, only a fraction, 1/n, of the field of view (FOV) may show considerable change during the motion cycle. A method is presented that improves the temporal resolution for a dynamic region by a factor, n, while maintaining spatial resolution at a cost of √n in signal‐to‐noise ratio (SNR). Temporal resolution is improved, or alternatively, total imaging time is reduced by reducing the number of phase encodes acquired for each temporal frame by 1/n. To eliminate aliasing, a representation of the signal from the static outer portion of the FOV is constructed using all the raw data. The k‐space data derived from this representation is subtracted from the original data sets, and the differences correspond to the dynamic portion of the FOV. Improved resolution results are presented in phantom studies, and in vivo phase contrast quantitative flow imaging.
1H‐MRS can detect aberrant glycosylation in tumour cells: a study of the HeLa cell line
Authors: Palma Alessandra , Grande Sveva , Rosi Antonella , Luciani Anna Maria , Guidoni Laura , Viti Vincenza 
Published: February 2011

AbstractGlycosylation is the most abundant and diverse form of post‐translational modification of proteins. Two types of glycans exist in glycoproteins: N‐glycans and O‐glycans often coexisting in the same protein. O‐glycosylation is frequently found on secreted or membrane‐bound mucins whose overexpression and structure alterations are associated with many types of cancer. Mucins have several cancer‐associated structures, including high levels of Lewis antigens characterized by the presence of terminal fucose. The present study deals with the identification of MR signals from N‐acetylgalactosamine and from fucose in HeLa cells by detecting a low‐field signal in one‐dimensional (1D) spectra assigned to the NH of N‐acetylgalactosamine and some cross peaks assigned to fucose in two‐dimensional (2D) spectra. The increase of Golgi pH by treatment with ammonium chloride allowed the N‐acetylgalactosamine signal assignment to be confirmed. Behaviour of MR peak during cell growth and comparison with studies from literature taken together made it possible to have more insight into the relationship between aberrantly processed mucin and the presence of non‐processed N‐acetylgalactosamine residues in HeLa cells. Fucose signals, tentatively ascribed to residues bound to galactose and to N‐acetylglucosamine, are visible in both intact cell and perchloric acid spectra. Signals assigned to fucose bound to galactose are more evident in ammonium chloride‐treated cells where structural changes of mucin‐related Lewis antigens are expected as a result of the higher Golgi pH. A common origin for the N‐acetylgalactosamine and fucose resonances attributing them to aberrantly processed mucin can be inferred from the present results. Copyright © 2011 John Wiley & Sons, Ltd.
The Journal of Pathology's approach to publication ethics and misconduct
Authors: Hall Peter A , Wixon Jo , Poulsom Richard 
Published: February 2011

AbstractThis Editorial highlights recent changes at The Journal of Pathology intended to improve our ability to detect, and we hope deter, instances of ethical misconduct among submissions made to the Journal, such as cases of guest authorship and plagiarism. We also discuss our experience to date and describe our policies for dealing with such cases. These changes are all encapsulated in our full online Author Guidelines. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Hypoxia‐inducible factor‐1 signalling promotes goblet cell hyperplasia in airway epithelium
Authors: Polosukhin Vasiliy V , Cates Justin M , Lawson William E , Milstone Aaron P , Matafonov Anton G , Massion Pierre P , Lee Jae Woo , Randell Scott H , Blackwell Timothy S 
Published: February 2011

AbstractGoblet cell hyperplasia is a common feature of chronic obstructive pulmonary disease (COPD) airways, but the mechanisms that underlie this epithelial remodelling in COPD are not understood. Based on our previous finding of hypoxia‐inducible factor‐1α (HIF‐1α) nuclear localization in large airways from patients with COPD, we investigated whether hypoxia‐inducible signalling could influence the development of goblet cell hyperplasia. We evaluated large airway samples obtained from 18 lifelong non‐smokers and 13 former smokers without COPD, and 45 former smokers with COPD. In these specimens, HIF‐1α nuclear staining occurred almost exclusively in COPD patients in areas of airway remodelling. In COPD patients, 93.2 ± 3.9% (range 65–100%) of goblet cells were HIF‐1α positive in areas of goblet cell hyperplasia, whereas nuclear HIF‐1α was not detected in individuals without COPD or in normal‐appearing pseudostratified epithelium from COPD patients. To determine the direct effects of hypoxia‐inducible signalling on epithelial cell differentiation in vitro, human bronchial epithelial cells (HBECs) were grown in air–liquid interface cultures under hypoxia (1% O2) or following treatment with a selective HIF‐1α stabilizer, (2R)‐[(4‐biphenylylsulphonyl)amino]‐N‐hydroxy‐3‐phenyl‐propionamide (BiPS). HBECs grown in hypoxia or with BiPS treatment were characterized by HIF‐1α activation, carbonic anhydrase IX expression, mucus‐producing cell hyperplasia and increased expression of MUC5AC. Analysis of signal transduction pathways in cells with HIF‐1α activation showed increased ERK1/2 phosphorylation without activation of epidermal growth factor receptor, Ras, PI3K‐Akt or STAT6. These data indicate an important effect of hypoxia‐inducible signalling on airway epithelial cell differentiation and identify a new potential target to limit mucus production in COPD. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Revisiting cancer immunoediting by understanding cancer immune complexity
Authors: Manjili Masoud H 
Published: February 2011

AbstractSince 1909, the cancer immunosurveillance concept has undergone four distinct eras. These include a general acceptance during 1957–1974, an abandonment during 1974–1996, resurrection during 1996–2001 in the form of an elegant theory of tumour immunoediting proposed by Robert Schreiber, and a retreat since 2006. Recently, in the Journal of Pathology, Ciampricotti et al reported an elegant experimental model designed by establishing RAG2−/−/MMTV‐NeuT mice. Using this, they demonstrated that the development and metastasis of HER‐2/neu‐positive spontaneous mammary carcinoma were not altered by the presence or absence of the adaptive immune system. Their fascinating results are a call to revisit controversial reports as to an effective role of the adaptive immune system in tumour inhibition versus tumour promotion or tolerance in the development of spontaneous carcinomas. Ciampricotti and colleagues present a strong case for revising our ideas of cancer immunoediting and appreciating the complexity of the interaction between cancer and the immune system. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.Invited commentary for Ciampricotti M et al. Development of metastatic HER2+ breast cancer is independent of the adaptive immune system. Journal of Pathology. 2011; 224: 56–66. http://dx.doi.org/10.1002/path.2837
Talin‐1 overexpression defines high risk for aggressive oral squamous cell carcinoma and promotes cancer metastasis
Authors: Lai Ming‐Tsung , Hua Chun‐Hung , Tsai Ming‐Hsui , Wan Lei , Lin Ying‐Ju , Chen Chih‐Mei , Chiu I‐Wen , Chan Carmen , Tsai Fuu‐Jen , Jinn‐Chyuan Sheu Jim 
Published: February 2011

AbstractOral squamous cell carcinoma (OSCC) is highly invasive and is associated with frequent tumour recurrences and lymph node metastases. Identification of genes involved in the aggressiveness of OSCC may provide new targets for clinical intervention. A genome‐wide study based on the Sty1 250K SNP array indicated the involvement of the Talin‐1 (TLN1) gene in the 9p13.3 amplicon, which was further validated by dual colour fluorescence in situ hybridization (FISH). Comparative analyses revealed that TLN1 was the most highly expressed integrin‐cytoskeleton cross‐linker that can trigger integrin activation. IHC analyses and mouse study also revealed an association between TLN1 overexpression and advanced OSCC with invasion to adjacent tissues. Survival analyses indicated a significant association between TLN1 genetic gain/overexpression and a reduced overall survival in patients. Functional knockdown by a dominant negative TLN1 fragment reduced cell growth and invasiveness in TLN1‐overexpressing cells via inactivation of downstream oncogenic signalling. The present study suggests an important role for TLN1 in oral cancer development. TLN1 overexpression could serve as a diagnostic marker for aggressive phenotypes and a potential target for treating OSCC. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Vitamin D status in paediatric patients with cancer
Authors: Sinha Akash , Avery Peter , Turner Steve , Bailey Simon , Cheetham Tim 
Published: February 2011

AbstractBackgroundChildren with malignant disease are at increased risk of bone disorders and cardiovascular disease. Vitamin D status may influence this risk and so we assessed vitamin D levels in children with malignant disease undergoing active treatment or surveillance post‐therapy.ProcedureThis was an outpatient‐based cross‐sectional study of 61 children with a history of malignancy (median age 11.1 years; range 1.5–24.4 years) and 60 control subjects (median age 8.4 years; range 0.2–18.0 years) attending hospital for the management of non‐malignant disorders. Serum vitamin D (25‐OH‐D), parathormone levels and bone biochemistry were determined. Vitamin D status and its relationship to age, sex, ethnicity, time of sampling and presence of malignant disease was determined.ResultsVitamin D status was suboptimal in 62% of cases (25‐OH‐D < 50 nmol/L [20 ng/ml]). Vitamin D deficiency (25‐OH‐D < 25 nmol/L [10 ng/ml]) was more common in children with malignant disease than controls (21.3% vs. 3.3%; P = 0.013). Month of sampling (P < 0.001), ethnicity (P < 0.001), older age (P = 0.011), and history of malignancy (P = 0.012) were associated with a poorer vitamin D status.ConclusionsVitamin D levels [25‐OH‐D] are lower in survivors of childhood cancer in comparison to control children with the majority either insufficient or deficient. Assessment and adequate replacement of vitamin D status may be of particular value in this group of children. Pediatr Blood Cancer 2011; 57: 594–598. © 2011 Wiley‐Liss, Inc.
AML1/RUNX1 gene point mutations in childhood myeloid malignancies
Authors: Migas Alexandr , Savva Natallia , Mishkova Olga , Aleinikova Olga V. 
Published: February 2011

AbstractBackgroundCurrently, it is widely accepted that one of the crucial players in adult leukemic transformation is the RUNX1 gene. However, there is little data available regarding whether mutations in this gene also contribute to pediatric leukemia, especially in childhood myeloid malignancies. Therefore we made a decision to screen patients with pediatric myeloid neoplasias for the presence of RUNX1 mutations in their samples.ProceduresPatients (n = 238) with diagnoses of de novo acute myeloid leukemia (AML) (n = 198), de novo myelodisplastic syndrome (MDS) (n = 16), therapy‐related AML (n = 9), juvenile myelomonocytic leukemia (JMML) (n = 15) were included in this study. All patients were Belarusians between the ages of 0 and 18 years.ResultsThe frequency of RUNX1 point mutations in the total group of patients with de novo AML was 3% and de novo MDS was 15%. Cooperation of point mutations in the RUNX1 and NRAS genes, and the cytogenetic abnormality, ‐7/7q‐, was demonstrated in children with therapy‐related AML. RUNX1 point mutations predominate in those de novo AML and MDS patients with a normal karyotype in leukemic cells. Frequency of RUNX1 point mutations was about 4% in a group of children with de novo AML aged 0–14 years diagnosed during the period of 1998–2009.ConclusionDuring the course of this investigation, valuable data were obtained concerning RUNX1 gene mutation frequencies in different clinical, morphological, and cytogenetic groups of patients with myeloid malignancies, and its cooperation with other molecular aberrations. Pediatr Blood Cancer 2011; 57: 583–587. © 2011 Wiley‐Liss, Inc.
Green composites from wheat protein isolate and Hildegardia Populifolia natural fabric
Authors: Jagadeesh Dani , Jeevan Pradsad Reddy D. , Varada Rajulu A. , Li R. 
Published: February 2011

AbstractCompletely biodegradable composites were prepared using modified wheat protein isolate (WPI) as matrix and the uniaxial natural fabric Hildegardia Populifolia as reinforcement. The WPI was cross‐linked with glutaraldehyde in the presence of glycerol plasticizer. These polymer composites were subsequently subjected to evaluation for their mechanical, morphological (SEM), thermal (TGA/DMA) properties, and biodegradation behavior. The mechanical properties such as tensile strength and flexural strength of the composite increased with increase in fabric loading up to 10% and decreased therefore. Further, the alkali treatment of the fabric and use of a coupling agent enhanced the mechanical properties. The scanning electron micrographs of the fractured surface of the composites indicated facilitation of better bonding between the matrix and reinforcement by the coupling agent. In case of thermal behavior, results indicated that the presence of fabric affected the thermal stability of polymer matrix. Biodegradability of the composites was also been studied by soil burial method, and the composites were found to degrade up to 95% in 35 days. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers