bluuebunny/crossref_metadata_2025_split huggingface dataset:
syn‐Allylstannation of N‐Acyliminium Intermediates by Tributyl[γ‐(silyloxy)allyl]stannanes: A Key Reaction for the Diastereoselective Synthesis of Polyhydroxypiperidines and Polyhydroxyazepanes
Authors: Chevallier Floris , Lumbroso Alexandre , Beaudet Isabelle , Le Grognec Erwan , Toupet Loïc , Quintard Jean‐Paul 
Published: June 2011

AbstractThe allylstannation of N‐alkenyl N‐acyliminium intermediates by tributyl[γ‐(silyloxy)allyl]stannanes afforded the expected adducts with a high syn‐selectivity (up to 99:1). Ensuing ring‐closing metathesis afforded dehydropiperidines or dehydroazepanes which were engaged in a stereoselective dihydroxylation reaction leading to polyhydroxypiperidines or polyhydroxyazepanes in good yields. This sequence was applied to a diastereoselective synthesis of (±)‐1‐deoxy‐gulonojirimycine.
Characterization of a Silver Modified PVCAc Electrode and Its Application as a Ag(I)‐Selective Potentiometric Sensor
Authors: Sejmanović D. M. , Petković B. B. , Budimir M. V. , Sovilj S. P. , Jovanović V. M. 
Published: June 2011

AbstractAn all solid‐state Ag(I) ion‐selective electrode has been prepared by simply immersing a glassy carbon rod coated with PVCAc, which contained plasticizer and additive but no ionophore, into the AgNO3 solution. The response of the electrode was linear with a Nernstian slope of 60.25 mV/decade within the concentration range from 1×10−1 to 1×10−5 M and with a detection limit of 4.25×10−6 M. The stability as an effect of various cations was defined. The electrode is suitable for use in high acidic solutions (pH<1 to 7) and has successfully been applied for the determination of silver(I) concentrations in different samples.
Ionic Liquid‐Based, Liquid‐Junction‐Free Reference Electrode
Authors: Cicmil Dimitrije , Anastasova Salzitsa , Kavanagh Andrew , Diamond Dermot , Mattinen Ulriika , Bobacka Johan , Lewenstam Andrzej , Radu Aleksandar 
Published: June 2011

AbstractIn this paper, we describe a new type of polymer membrane‐based reference electrode (RE) based on ionic liquids (ILs), in both liquid‐contact (LCRE) and solid‐contact reference electrode (SCRE) forms. The ILs used were bis(trifluoromethane sulfonyl)amid with 1‐alkyl‐3‐methyl‐imidazolium as well as phosphonium and ammonium cations. In addition to their charge stabilisation role, it was found that the ILs also functioned as effective plasticizers in the PVC matrix. The LCREs and SCREs were prepared using the same design as their corresponding indicator electrodes. LCREs were prepared by casting in glass rings while SCREs were prepared on platforms made using screen‐printing technology, with poly(3‐octylthiophene‐2,5 diyl) (POT) as the intermediate polymer. After potentiometric characterization of the response mechanism, the practical performance of the REs was studied using potentiometric titrations (Pb2+ and pH), and characterised using cyclic voltammetry and impedance spectroscopy. All results were compared via parallel experiments in which the novel RE was substituted by a conventional double junction Ag/AgCl reference electrode. The mechanism of response is most likely based on a limited degree of partitioning of IL ions into the sample thereby defining aquo‐membrane interfacial potential. Despite their simple nature and construction, the REs showed excellent signal stability, and performed well in the analytical experiments. The identical mode of fabrication to that of the equivalent indicator (or Ion‐Selective Electrode, ISE) will facilitate mass‐production of both indicator and reference electrode using the same fabrication line, the only difference being the final capping membrane composition.
An Electrochemical Immunobiosensor for Direct Detection of Veterinary Drug Residues in Undiluted Complex Matrices
Authors: Khor Sook Mei , Liu Guozhen , Peterson Joshua R. , Iyengar Sridhar G. , Gooding J. Justin 
Published: June 2011

AbstractAn electrochemical immunobiosensor is developed that allows the detection of small molecules, such as drugs, in undiluted complex samples, with no washing or rinsing steps via a displacement assay. This is achieved using an interface comprised of a mixed layer of oligo(phenylethynylene) molecular wire (MW), to allow electrochemical communication, and oligo(ethylene glycol) (OEG) to control the interaction of proteins and electroactive interferences with the electrode surface. The mixed layer is formed from in situ‐generated aryl diazonium cations. To the distal end of the MW, a redox probe 1,1′‐di(aminomethyl)ferrocene (FDMA) is attached followed by an epitope (the structural feature the antibody selectively recognizes) to which an antibody would bind. Association or dissociation of the antibody with the sensing interface causes a modulation of the ferrocene electrochemistry. Antibody complexed electrodes are exposed to samples containing spiked enrofloxacin (unbound target analyte), in milk and environmental water and interrogated using square wave voltammetry (SWV). The lowest detected concentration of free enrofloxacin was 10 pg mL−1 in phosphate buffer, 50 mM, pH 7. For free enrofloxacin detection in undiluted complex matrices, by adding disodium EDTA (50 mM), the recovery obtained was 94.1 % in skim milk and 88.5 % in stream water, respectively as compared to clean phosphate buffer. The immunobiosensor response time was 10–15 minutes. The sensor performance in milk was shown to be superior to a standard method based on Liquid Chromatography Mass Spectroscopy (LC‐MS/MS).
Evidence of a changing size–frequency distribution of landslides in the Kyrgyz Tien Shan, Central Asia
Authors: Schlögel Romy , Torgoev Isakbek , De Marneffe Cédric , Havenith Hans‐Balder 
Published: June 2011

ABSTRACTThere is a strong possibility that environmental change (whether climate or land use) will be manifest as changes in the size–frequency distribution of landslides. Here, evidence is presented for this from western Kyrgyzstan, Central Asia. Remote sensing and spatial analysis have been applied to map mass movements in the central part of the Maily‐Say Valley and to detect recent landslide activations. The evolution of landslide activity over the past 50 years has been analysed on the basis of pre‐existing landslide maps and new analyses of aerial photographs as well as Quickbird images. Five inventories were produced for the years 1962 (based on the existing map of 1962 and aerial photographs of 1962), 1984 (based on the existing map of 1977 and aerial photographs of 1984), 1996 (based on aerial photographs of 1996), 2002 (based on the existing map of 2003 and Quickbird imagery of 2002) and 2007 (based on Quickbird imagery of 2007). The geomorphologic features contained in the catalogues represent the landslide bodies observed from remote imagery of the corresponding year. Mapped landslides are generally considered as the result of a series of slope failure events. Size–frequency analyses applied to the five landslide inventories show that both the number and size of unstable slopes increased from 1962 (162 objects) to 2007 (208 objects) and the power‐law exponent decreased over time. This changing power‐law exponent may indicate that landslide‐related hazards are increasing. This tendency is documented in more detail for two active landslide zones, one in the main valley and one located to the west of it. Landslide detection methods were used to assist the evolution of slope instabilities. Choosing appropriate thresholds, the image subtraction method based on normalized difference vegetation index (NDVI) allowed accurate detection of new sliding activation in these two zones. This confirmed the results of the more extensive survey that there is a systematic shift in power law exponents and size–frequency distributions for Central Asian landslides. Copyright © 2011 John Wiley & Sons, Ltd.
IMPROVING FOOD CHOICES AMONG SUPPLEMENTAL NUTRITION ASSISTANCE PROGRAM RECIPIENTS
Authors: You Wen , Mitchell Paul D. , Nayga Rodolfo M. 
Published: June 2011

SUMMARYWe used a principal–agent framework to examine the feasibility of two proposed modifications to the Supplemental Nutrition Assistance Program with the goal of encouraging healthier food choices among program participants. Specifically, we analyzed two types of contract: a restricted contract and an incentive contract. The restricted contract did not allow the purchase of unhealthy foods with program benefits, but compensated participants by increasing total benefits. The incentive contract provided increased benefits that varied according to the percentage of healthy foods purchased with program benefits. The theoretical results revealed the mechanisms for the two alternative contracts, the conditions under which each would be effective, and the key empirical questions to be examined for future policy analysis. Copyright © 2011 John Wiley & Sons, Ltd.
Identification of high‐risk stage II and stage III colorectal cancer by analysis of MMP‐21 expression
Authors: Wu Tao , Li Yi , Liu Xiaohong , Lu Jianguo , He Xianli , Wang Qing , Li Jipeng , Du Xilin 
Published: June 2011

AbstractBackgroundThe expression of matrix metalloproteinase‐21 (MMP‐21) has been shown to be elevated in some solid tumor and thought to enhance tumor invasion and metastasis ability. In the present study, we investigated the expression of MMP‐21 and its association with prognosis in stage II and III colorectal cancer.MethodsMMP‐21 expression was investigated in 286 cases of colorectal cancer by immunohistochemistry assay. Statistical analysis was utilized to evaluate the association of MMP‐21 expression with clinicopathological characters and overall survival of patients with stage II and III colorectal cancer.ResultsMMP‐21 expression was significantly higher in colorectal cancer, compared with that in normal epithelial tissue. And it also correlated with tumor invasion, lymph node metastasis, and distant metastasis of colorectal cancer. MMP‐21 was also proved to be an independent prognostic factor in patients with stage II as well as stage III colorectal cancer. However, no correlations between MMP‐21 expression and patients' age, sex, tumor location, or differentiation status were detected.ConclusionThese results suggested the potential role of MMP‐21 in the invasion and metastasis process of human colorectal cancer. It could also be a novel molecular marker to predict prognosis of patients with stage II and stage III colorectal cancer. J. Surg. Oncol. 2011; 104:787–791. © 2011 Wiley Periodicals, Inc.
Patterned Hydrogel Substrates for Cell Culture with Electrohydrodynamic Jet Printing
Authors: Poellmann Michael J. , Barton Kira L. , Mishra Sandipan , Johnson Amy J. Wagoner 
Published: June 2011

AbstractCells respond to and are directed by physiochemical cues in their microenvironment, including geometry and substrate stiffness. The development of substrates for cell culture with precisely controlled physiochemical characteristics has the potential to advance the understanding of cell biology considerably. In this communication, E‐jet printing is introduced as a method for creating high‐resolution protein patterns on substrates with controlled elasticity. It is the first application of E‐jet printing on a soft surface. Protein spots as small as 5 µm in diameter on polyacrylamide are demonstrated. The patterned hydrogels are shown to support cell attachment and spreading. Polyacrylamide substrates patterned by E‐jet printing may be applied to further the study of cellular mechanobiology.
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A single‐nucleotide polymorphism in tumor suppressor gene SEL1L as a predictive and prognostic marker for pancreatic ductal adenocarcinoma in Caucasians
Authors: Liu Qian , Chen Jinyun , Mai Billy , Amos Christopher , Killary Ann M. , Sen Subrata , Wei Chongjuan , Frazier Marsha L. 
Published: June 2011

AbstractSEL1L is a putative tumor suppressor gene that is frequently down‐regulated in pancreatic ductal adenocarcinoma (PDA). A single‐nucleotide polymorphism (SNP) rs12435998 in intron3 of SEL1L has previously been reported to be associated with susceptibility to Alzheimer's disease. We hypothesized that this SNP may influence clinical outcomes of patients with PDA. We analyzed DNA samples from 497 Caucasian patients with pathologically confirmed primary PDA. Of these, 98 had been enrolled in a clinical trial of neoadjuvant chemo‐radiotherapy and 77 of the 98 had subsequently undergone pancreaticoduodenectomy (PD). We performed Kaplan–Meier analysis to evaluate the correlation between different SNP genotypes and age at diagnosis, survival time after diagnosis, and survival time after PD. In nonsmokers, we found a significant difference in median age at diagnosis between variant genotypes (AG/GG) carriers and wild‐type genotype (AA) carriers (58 vs. 62 yr; log‐rank test, P = 0.017). Patients with variant genotypes also showed an increased hazard ratio (HR) of 1.45 [95% confidence interval (CI), 1.07–1.97] relative to wild‐type genotype. Among the patients in the clinical trial, the variant genotypes carriers had a median post‐PD survival time that was 34.7 months shorter than wild‐type genotype carriers (log‐rank test, P = 0.019; HR, 1.91; 95% CI, 1.09–3.34). Our results suggest that the rs12435998 SNP in SEL1L gene plays a role in modifying age at diagnosis of PDA in Caucasian nonsmokers. In addition, this SNP may serve as a prognostic marker in PDA patients who undergo the same or similar treatment as the clinical trials. © 2011 Wiley Periodicals, Inc.
Three‐dimensional phase contrast angiography of the mouse aortic arch using spiral MRI
Authors: Janiczek Robert L. , Blackman Brett R. , Roy R. Jack , Meyer Craig H. , Acton Scott T. , Epstein Frederick H. 
Published: June 2011

AbstractAtherosclerosis is a complex disease whose spatial distribution is hypothesized to be influenced by the local hemodynamic environment. The use of transgenic mice provides a mechanism to study the relationship between hemodynamic forces, most notably wall shear stress (WSS), and the molecular factors that influence the disease process. Phase contrast MRI using rectilinear trajectories has been used to measure boundary conditions for use in computational fluid dynamic models. However, the unique flow environment of the mouse precludes use of standard imaging techniques in complex, curved flow regions such as the aortic arch. In this article, two‐dimensional and three‐dimensional spiral cine phase contrast sequences are presented that enable measurement of velocity profiles in curved regions of the mouse vasculature. WSS is calculated directly from the spatial velocity gradient, enabling WSS calculation with a minimal set of assumptions. In contrast to the outer radius of the aortic arch, the inner radius has a lower time‐averaged longitudinal WSS (7.06 ± 0.76 dyne/cm2 vs. 18.86 ± 1.27 dyne/cm2; P < 0.01) and higher oscillatory shear index (0.14 ± 0.01 vs. 0.08 ± 0.01; P < 0.01). This finding is in agreement with humans, where WSS is lower and more oscillatory along the inner radius, an atheroprone region, than the outer radius, an atheroprotective region. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc.
Evaluation of MRI resolution affecting trabecular bone parameters: Determination of acceptable resolution
Authors: Kim Namkug , Lee June‐Goo , Song Youngkyu , Kim Hengjun J. , S. Yeom Jin , Cho Gyunggoo 
Published: June 2011

AbstractThe objective of this study is to evaluate the effect of MR image resolution on trabecular bone parameters and to determine the acceptable resolution that can be accurately analyzed to assess structural parameters. Ten distal femoral condyle specimens of 1 × 1 × 1 cm3 were scanned with a 4.7‐T Bruker BioSpec MRI scanner using a three‐dimensional fast large‐angle spin‐echo sequence with various iso‐cubic voxels sizes (65, 130, 160, 196, 230, and 260 μm). Otsu thresholding was applied to identify voxels containing bone. Conventional bone parameters, structural bone parameters, and skeleton‐based local trabecular thickness (slTB.Th) were evaluated. The Bland–Altman method and correlation indicated that the conventional and structural bone parameters were preserved with an iso‐cubic voxel size up to 230 μm (r > 0.932 and r > 0.843, respectively). In addition, slTB.Th derived from the highest resolution images (65 μm iso‐cubic voxel size), correlated well (r > 0.833) with the values computed from lower resolution images, up to 230 μm, which is twice typical human trabecular thickness range (100–150 μm). The outcome of this study suggests that the various bone parameters were well preserved up to 230 μm images. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Thalamus segmentation based on the local diffusion direction: A group study
Authors: Mang Sarah C. , Busza Ania , Reiterer Susanne , Grodd Wolfgang , Klose and Uwe 
Published: June 2011

AbstractFast and accurate segmentation of deep gray matter regions in the brain is important for clinical applications such as surgical planning for the placement of deep brain stimulation implants. Mapping anatomy from stereotactic atlases to patient data is problematic because of individual differences in subject anatomy that are not accounted for by commonly used atlases. We present a segmentation method for individual subject diffusion tensor MR data that is based on local diffusion information to identify subregions of the thalamus. We show the correspondence of our segmentation results to anatomy by comparison with stereotactic atlas data. Importantly, we verify the consistency of our segmentation by evaluating the method on 63 healthy volunteers. Our method is fast, reliable, and independent of any segmentation before the classification of regions within the thalamus. It should, therefore, be useful in clinical applications. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Evaluation of a vessel‐tracking‐based technique for dynamic targeting in human liver
Authors: Kokuryo Daisuke , Kumamoto Etsuko , Takao Yoshie , Fujii Susumu , Kaihara Toshiya , Kuroda Kagayaki 
Published: June 2011

AbstractThe purpose of this study was to evaluate a novel vessel‐tracking‐based technique for tracking of human liver. The novelty of the proposed technique is that it measures the translation and deformation of a local tissue region based on the displacements of a set of vessels of interest instead of the entire organ. The position of the target point was estimated from the relative positions of the center‐of‐masses of the vessels, assuming that the topological relationship between the target point and center‐of‐masses is unchanged during breathing. To reduce inaccuracy due to the delay between vessel image acquisition and sonication, the near‐future target position was predicted based on the vessel displacements in the images extracted from an image library acquired before the tracking stage. Experiments on healthy volunteers demonstrated that regardless of the respiratory condition, appropriate combinations of three center‐of‐masses from the vessels situated around the target‐tissue position yielded an estimation error of less than 2 mm, which was significantly smaller than that obtained when using a single center‐of‐mass trio. The effect of the tracking delay was successfully compensated, with a prediction error of less than 3 mm, by using over four images selected from the image library. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Bleomycin‐induced lung injury in mice investigated by MRI: Model assessment for target analysis
Authors: Babin Anna L. , Cannet Catherine , Gérard Christelle , Saint‐Mezard Pierre , Page Clive P. , Sparrer Helmut , Matsuguchi Tetsuya , Beckmann Nicolau 
Published: June 2011

AbstractMagnetic resonance imaging (MRI) has been used to follow the course of bleomycin‐induced lung injury in mice and to investigate two knockout mouse lines with the aim of providing potential therapeutic targets. Bleomycin (0.25 mg/kg) was administered intranasally six times, once a day. MRI was carried out on spontaneously breathing animals up to day 70 after bleomycin. Neither cardiac nor respiratory gating was applied during image acquisition. A long lasting response following bleomycin has been detected by MRI in the lungs of male C57BL/6 mice. Histology showed that, from day 14–70 after bleomycin, fibrosis was the predominant component of the injury. Female C57BL/6 mice displayed a smaller response than males. Bleomycin‐induced injury was significantly more pronounced in C57BL/6 than in Balb/C mice. MRI and histology demonstrated a protection against bleomycin insult in female heterozygous and male homozygous cancer Osaka thyroid kinase knockout animals. In contrast, no protection was seen in cadherin‐11 knockout animals. In summary, MRI can quantify, in spontaneously breathing mice, bleomycin‐induced lung injury. With the ability for repetitive measurements in the same animal, the technique is attractive for in vivo target analysis and compound profiling in this murine model. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Arterial spin labeling angiography using a triple inversion recovery prepulse
Authors: Andia Marcelo E. , Botnar Rene M. 
Published: June 2011

AbstractArterial spin labeling is a well‐known noninvasive angiography technique, which does not necessitate the use of a contrast agent. arterial spin labeling is still clinically underused because of several challenges: (1) long scan times because of the need for two acquisitions (labeled and nonlabeled datasets), (2) sensitivity to spatial misregistration because of the need for image subtraction, and (3) the need for precise planning and choice of an optimal inversion delay for best blood‐to‐background contrast. In this work, we propose a new arterial spin labeling method based on a triple‐inversion‐recovery sequence‐arterial spin labeling. This approach exploits the ability of two nonselective inversion recovery prepulses to null the background signal over a wide range of T1 values, while maintaining the signal of labeled blood using a third slab selective inversion pulse. This technique therefore allows the acquisition of angiograms with a flexible inversion delay, easier planning procedure and no need for subtraction. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Seeing the smoking gun: a sensitive and specific method to visualize loss of the tumour suppressor, fumarate hydratase, in human tissues
Authors: Maxwell Patrick H. 
Published: June 2011

AbstractIn this issue of the Journal of Pathology, Bardella et al report a method for identifying tumours that lack fumarate hydratase. The approach they use is immunodetection of proteins that have been modified by a non‐enzymatic reaction of thiol groups in proteins with fumarate, which is termed succination. Validation included the use of mice with targeted inactivation of fumarate hydratase in the kidney, extensive studies of normal human tissues and examination of over 1000 specimens from human cancers not associated with FH mutations. Detection of protein succination is likely to provide a sensitive and specific method for pathologists to identify the small proportion of papillary renal cell carcinomas that are associated with germline mutations in the FH gene. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.