bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemical transfection of dye‐conjugated microRNA precursors for microRNA functional analysis of M2 macrophages
Authors: Ng Yee Seng , Roca Hernan , Fuller David , Sud Sudha , Pienta Kenneth J. 
Published: December 2011

AbstractMicroRNAs (miRNAs) are short noncoding ribonucleic acids known to affect gene expression at the translational level and there is mounting evidence that miRNAs play a role in the function of tumor‐associated macrophages (TAMs). To aid the functional analyses of miRNAs in an in‐vitro model of TAMs known as M2 macrophages, a transfection method to introduce artificial miRNA constructs or miRNA molecules into primary human monocytes is needed. Unlike differentiated macrophages or dendritic cells, undifferentiated primary human monocytes have been known to show resistance to lentiviral transduction. To circumvent this challenge, other techniques such as electroporation and chemical transfection have been used in other applications to deliver small gene constructs into human monocytes. To date, no studies have compared these two methods objectively to evaluate their suitability in the miRNA functional analysis of M2 macrophages. Of the methods tested, the electroporation of miRNA‐construct containing plasmids and the chemical transfection of miRNA precursor molecules are the most efficient approaches. The use of a silencer siRNA labeling kit (Ambion) to conjugate Cy 3 fluorescence dyes to the precursor molecules allowed the isolation of successfully transfected cells with fluorescence‐activated cell sorting. The chemical transfection of these dye‐conjugated miRNA precursors yield an efficiency of 37.5 ± 0.6% and a cell viability of 74 ± 1%. RNA purified from the isolated cells demonstrated good quality, and was fit for subsequent mRNA expression qPCR analysis. While electroporation of plasmids containing miRNA constructs yield transfection efficiencies comparable to chemical transfection of miRNA precursors, these electroporated primary monocytes seemed to have lost their potential for differentiation. Among the most common methods of transfection, the chemical transfection of dye‐conjugated miRNA precursors was determined to be the best‐suited approach for the functional analysis of M2 macrophages. J. Cell. Biochem. 113: 1714–1723, 2012. © 2012 Wiley Periodicals, Inc.
Lanthanum chloride bidirectionally influences calcification in bovine vascular smooth muscle cells
Authors: Zhao Wen‐Hua , Gou Bao‐Di , Zhang Tian‐Lan , Wang Kui 
Published: December 2011

AbstractVascular calcification (VC) is frequent prevalence in patients with chronic kidney disease (CKD) and atherosclerosis. Lanthanum carbonate is used as an orally administered phosphate‐binding agent to reduce the gastrointestinal absorption of phosphate and ameliorate VC in advanced CKD. In this study, we used bovine vascular smooth muscle cells as a model VC in vitro and studied the effects of lanthanum chloride on calcium deposition. Exposure of cells to LaCl3 at the concentration of 0.1 µM suppressed the β‐glycerophosphate‐induced alkaline phosphatase activity and calcium deposition. Furthermore, LaCl3 upregulated the β‐glycerophosphate‐suppressed expression of calcium‐sensing receptor. In contrast to the inhibitory effect of LaCl3 on calcium deposition, higher level lanthanum (50 µM) was found to promote immediately precipitation of calcium phosphate in cell culture medium. At this concentration, LaCl3 was found to induce cell apoptosis which involves caspases‐9 and ‐3. These data indicate that the promotory effect of LaCl3 on calcium deposition is likely mediated by induction of apoptosis. Our in vitro findings do suggest that, in the context of raised lanthanum, greater attention should be paid to potential toxic effects associated to the use of lanthanide‐based drugs. J. Cell. Biochem. 113: 1776–1786, 2012. © 2011 Wiley Periodicals, Inc.
Evaluation of BMP‐2 gene‐activated muscle grafts for cranial defect repair
Authors: Liu Fangjun , Porter Ryan M. , Wells James , Glatt Vaida , Pilapil Carmencita , Evans Christopher H. 
Published: December 2011

AbstractLarge, osseous, segmental defects heal poorly. Muscle has a propensity to form bone when exposed to an osteogenic stimulus such as that provided by transfer and expression of cDNA encoding bone morphogenetic protein‐2 (BMP‐2). The present study evaluated the ability of genetically modified, autologous muscle to heal large cranial defects in rats. Autologous grafts (8 mm × 2 mm) were punched from the biceps femoris muscle and transduced intraoperatively with recombinant adenovirus vector containing human BMP‐2 or green fluorescent protein cDNA. While the muscle biopsies were incubating with the vector, a central parietal 8 mm defect was surgically created in the calvarium of the same animal. The gene‐activated muscle graft was then implanted into the cranial defect. After 8 weeks, crania were examined radiographically, histologically, and by micro‐computed tomography and dual energy X‐ray absorptiometry. Although none of the defects were completely healed in this time, muscle grafts expressing BMP‐2 deposited more than twice as much new bone as controls. Histology confirmed the anatomical integrity of the newly formed bone, which was comparable in thickness and mineral density to the original cranial bone. This study confirms the in vivo osteogenic properties of genetically modified muscle and suggests novel strategies for healing bone. © 2011 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1095–1102, 2012
Application of stable carbon isotopes for reconstructing salt‐marsh floral zones and relative sea level, New Jersey, USA
Authors: Kemp Andrew C. , Vane Christopher H. , Horton Benjamin P. , Engelhart Simon E. , Nikitina Daria 
Published: December 2011

AbstractWe investigated use of δ13C in bulk organic sediment to define the botanical origin of samples preserved in coastal sediment as a means to reconstruct relative sea level in New Jersey, USA. Modern transects at three sites demonstrated that low and high salt‐marsh floral zones dominated by C4 species (Spartina alterniflora and Spartina patens) were associated with sediment δ13C values between −18.9‰ and −15.8‰ and occurred from mean tide level (MTL) to mean higher high water (MHHW). Brackish transitional settings vegetated by Phragmites australis with Iva fructescens and Typha sp. (C3 species) and freshwater upland samples (C3 species) were characterized by bulk sediment δ13C values of −27.0‰ to −22.0‰ and existed above MHHW. Parallel transects at one site suggested that intra‐site variability was not discernible. The utility of δ13C values for reconstructing relative sea level in New Jersey is limited by an inability to differentiate between brackish sediments related to sea level and freshwater upland samples. To facilitate this distinction in a 4.4 m core, we used a multi‐proxy approach (δ13C values with presence or absence of agglutinated foraminifera) to recognize indicative meanings for four sample types. Sediment with δ13C values greater than −18.9‰ was derived from a vegetated salt‐marsh and formed between MTL and MHHW. Sediment with δ13C values less than −22.0‰ and containing agglutinated foraminifera formed in a brackish transitional zone between MHHW and highest astronomical tide (HAT). This is the narrowest elevational range of the four sample types and most precise sea‐level indicator. Sediment with δ13C values less than −22.0‰ and lacking foraminifera can only constrain the upper bound of former sea level. Samples with intermediate values (−22.0‰ to −18.9‰) formed between MTL and HAT. Using these indicative meanings and radiocarbon dates, we suggest that a transition from brackish to salt‐marsh δ13C values recorded in the core took approximately 350 years (from 1800 to 1450 cal. a BP). Copyright © 2011 John Wiley & Sons, Ltd.
The dependence of radiofrequency induced pacemaker lead tip heating on the electrical conductivity of the medium at the lead tip
Authors: Langman Deborah A. , Goldberg Ira B. , Judy Jack , Paul Finn J. , Ennis Daniel B. 
Published: December 2011

AbstractRadiofrequency induced pacemaker lead tip heating is one of the main reasons magnetic resonance imaging (MRI) is contraindicated for patients with pacemakers. The objective of this work was to evaluate the dependence of pacemaker lead tip heating during MRI scanning on the electrical conductivity of the medium surrounding the pacemaker lead tip. The effect of conductivity was measured using hydroxyethyl cellulose, polyacrylic acid, and saline with conductivities ranging from 0 to 3 S/m which spans the range of human tissue conductivity. The maximum lead tip heating observed in polyacrylic acid was 50.4°C at 0.28 S/m, in hydroxyethyl cellulose the maximum was 36.8°C at 0.52 S/m, and in saline the maximum was 12.5°C at 0.51 S/m. The maximum power transfer theorem was used to calculate the relative power deposited in the solution based on the characteristic impedance of the pacemaker lead and test solution impedance. The results demonstrate a strong correlation between the relative power deposited and pacemaker lead tip heating for hydroxyethyl cellulose and saline solutions. Maximum power deposition occurred when the impedance of the solution matched the pacemaker lead impedance. Pacemaker lead tip heating is dependent upon the electrical conductivity of the solution at the lead tip and should be considered when planning in vitro gel or saline experiments. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Stretchable coil arrays: Application to knee imaging under varying flexion angles
Authors: Nordmeyer‐Massner J. A. , De Zanche N. , Pruessmann K. P. 
Published: December 2011

AbstractTo fit high‐density receiver arrays for MRI closely around individual target anatomies, there is a need to provide a high degree of geometric adjustability with ease of handling and patient comfort. In this work, this is accomplished by the construction of a coil array that is stretchable such that it automatically conforms to a given anatomy's shape and size. Stretchability is implemented by creating the coil conductors from braided wire mounted on an elastic textile substrate. The signal‐to‐noise ratio yield of such coils is measured by MRI experiments at 3 T, and the signal‐to‐noise ratio effect of coil stretching is investigated with and without adjustment of the matching between each coil and the respective preamplifier. Four‐channel and eight‐channel arrays of stretchable receiver coils are evaluated in phantoms as well as for in vivo imaging of the human knee. Exploiting stretchability, it is demonstrated that the knee can be imaged under varying flexion angles up to 60° while maintaining closely coupled array detection, high signal‐to‐noise ratio, and uniform coverage of the entire joint. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Microscopic diffusivity compartmentation in formalin‐fixed prostate tissue
Authors: Bourne Roger M. , Kurniawan Nyoman , Cowin Gary , Stait‐Gardner Timothy , Sved Paul , Watson Geoffrey , Price William S. 
Published: December 2011

AbstractMR microimaging at 16.4 T with 40‐μm isotropic voxels was used to investigate compartmentation of water diffusion in formalin‐fixed prostate tissue. Ten tissue samples (∼ 28 mm3 each) from five organs were imaged. The mean diffusivity of epithelial, stromal, and ductal/acinar compartments was estimated by two methods: (1) manual region of interest selection and (2) Gaussian fitting of voxel diffusivity histograms. For the region of interest‐method, the means of the tissue sample compartment diffusivities were significantly different (P < 0.001): 0.54 ± 0.05 μm2/ms for epithelium‐containing voxels, 0.91 ± 0.17 μm2/ms for stroma, and 2.20 ± 0.04 μm2/ms for saline‐filled ducts. The means from the histogram method were also significantly different (P < 0.001): 0.45 ± 0.08 μm2/ms for epithelium‐containing voxels, 0.83 ± 0.16 μm2/ms for stroma, 2.21 ± 0.02 μm2/ms for duct. Estimated partial volumes of epithelial, stromal, and ductal/acinar compartments in a “tissue only” subvolume of each sample were significantly different (P < 0.02) between cancer and normal tissue for all three compartments. It is concluded that the negative correlation between apparent diffusion coefficient and cancer Gleason grade observed in vivo results from an increase of partial volume of epithelial tissue and concomitant decrease of stromal tissue and ductal space. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Association of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 status with total choline concentration and tumor volume in breast cancer patients: An MRI and in vivo proton MRS study
Authors: Sah Rani G. , Sharma Uma , Parshad Rajinder , Seenu Vurthaluru , Mathur Sandeep R. , Jagannathan Naranamangalam R. 
Published: December 2011

AbstractThe association of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2) status of breast cancer patients with total choline (tCho) concentration and tumor volume was investigated using in vivo proton magnetic resonance spectroscopy and MRI at 1.5 T. Values for tCho concentration were determined in 120 locally advanced breast cancer patients (stages IIB, IIIA, IIIB, and IIIC), 31 early breast cancer patients (stage IIA), 38 patients with benign lesions, and 37 controls. Significantly higher tCho concentration and lower tumor volume were observed in early breast cancer patients compared to locally advanced breast cancer patients (P < 0.05). tCho concentration and tumor volume did not correlate with age and menstruation. tCho cutoff values were obtained for the differentiation of malignant from benign breast tissues (2.54 mmol/kg); malignant versus normal (1.45 mmol/kg) and benign versus normal tissues (0.82 mmol/kg). Estrogen receptor negative patients showed significantly larger tumor volumes, indicating higher angiogenesis with aggressive tumor behavior. Nontriple negative and triple positive patients had a significantly higher tCho concentration compared to triple negative patients (P < 0.05), indicating complex molecular mechanism of cell proliferation and the molecular heterogeneity of breast lesions. The results indicate the potential use of integration of breast 1H magnetic resonance spectroscopy in diagnostic workup. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
In vivo chromium‐enhanced MRI of the retina
Authors: Chan Kevin C. , Fan Shu‐Juan , Zhou Iris Y. , Wu Ed X. 
Published: December 2011

AbstractChromium (Cr) has been used histologically to stabilize lipid fractions in the retina and is suggested to enhance oxidizable lipids in brain MRI. This study explored the feasibility, sensitivity, and specificity of in vivo chromium‐enhanced MRI of retinal lipids by determining its spatiotemporal profiles and toxic effect after intravitreal Cr(VI) injection to normal adult rats. One day after 3 μL Cr(VI) administration at 1–100 mM, the retina exhibited a dose‐dependent increase in T1‐weighted hyperintensity until 50 mM. Time‐dependently, significant T1‐weighted hyperintensity persisted up to 2 weeks after 10 mM Cr(VI) administration. Three‐dimensional chromium‐enhanced MRI of ex vivo normal eyes at isotropic 50‐μm resolution showed at least five alternating bands across retinal layers, with the outermost layer being the brightest. This agreed with histology indicating alternating lipid contents with the highest level in the photoreceptor layer of the outer retina. Although Cr(VI) reduction may induce oxidative stress and depolymerize microtubules, manganese‐enhanced MRI after chromium‐enhanced MRI showed a dose‐dependent effect of Cr toxicity on manganese uptake and axonal transport along the visual pathway. These results potentiated future longitudinal chromium‐enhanced MRI studies on retinal lipid metabolism upon further optimization of Cr doses with visual cell viability. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Structure of Plasma‐Deposited Copolymer Films Prepared from Acrylic Acid and Styrene: Part I Dependence on the Duty Cycle
Authors: Fahmy Alaa , Mix Renate , Schönhals Andreas , Friedrich Jörg 
Published: December 2011

AbstractCopolymers of acrylic acid and styrene (AA/S) were prepared by pulsed plasma deposition and their structures were studied in dependence on the duty cycle (DC) for a fixed composition of 1:1. As a result, low values of DC doses preserve the structure of monomers in the plasma deposited polymers while high DC leads to a higher degree of fragmentation and a loss in regular structure. Regarding plasma copolymerisation as a feasible method to finish surfaces with a definite number of functional groups it is necessary to characterize both, the chemical nature and the physical properties of the deposited layer. Therefore, a combination of different methods was employed for the characterization of thin plasma copolymer films (FTIR, dielectric spectroscopy, differential scanning calorimetry, X‐ray photoelectron spectroscopy (XPS)). Special attention was paid on the unambiguous identification of COOH groups at the surface after derivatization with trifluoroethanol by XPS and in the volume by FTIR. The glass transition temperature of the copolymer system is lower than that for the both plasma deposited homopolymers and increases with the DC in difference to plasma deposited poly(acrylic acid). The dielectric measurements showed that the plasma deposited films were not thermally stable and underwent an undesired post‐plasma chemical reaction. The results obtained by dielectric spectroscopy are discussed in detail in comparison with the data from FTIR and XPS measurements.magnified image
Nitrogen Introduction in pp‐HMDSO Thin Films Deposited by Atmospheric Pressure Dielectric Barrier Discharge: An XPS Study
Authors: Maurau Rémy , Boscher Nicolas D. , Guillot Jérôme , Choquet Patrick 
Published: December 2011

AbstractWe report on the change of chemistry involved by molecular nitrogen in the deposition process of pp‐HMDSO thin films with an AP‐DBD, using HMDSO as chemical precursor. By modifying the composition of the main gas from pure argon to pure nitrogen, thin films composition varied from SiOC:H to SiOCN:H. A small amount of nitrogen favours polymer chain propagation, by consuming species responsible for chain termination and playing a role in propagation phase. Higher nitrogen content leads to more cross‐linked coatings. The use of optical emission spectroscopy together with FT‐IR and XPS is shown to be relevant to study such processes.magnified image
Trypsin‐like proteolytic contamination of commercially available psa purified from human seminal fluid
Authors: Manning Michael L. , Kostova Maya , Williams Simon A. , Denmeade Samuel R. 
Published: December 2011

AbstractBACKGROUNDProstate‐Specific Antigen (PSA) is a serine protease whose expression is maintained in all stages of prostate cancer. A role for PSA in the pathobiology for prostate cancer has not been firmly established. Experimental studies to date support a role for PSA through mechanisms such as release or processing of growth factors and degradation of the extracellular matrix. Exposure of prostate cancer cells to exogenous PSA also results in gene expression changes. These in vitro and biochemical assays rely on the use of commercially available PSA. Contamination of these commercial preparations can significantly impact the results of these in vitro studies.METHODSWe characterized PSA and trypsin‐like activity of PSA preparations obtained from three commercial sources: Calbiochem, Fitzgerald, and AbD Serotec. Silver stained gels were used to compare the purity of each preparation and mass spectrometry was performed to characterize contaminating proteases.RESULTSPSA activity varied between PSA preparations with AbD Serotec PSA having highest degree of activity. Significant trypsin‐like activity, which was inhibited by aprotinin, was observed in PSA preparations from Calbiochem and Fitzgerald, but not AbD Serotec. These former two PSA preparations also contained the greatest degree of non‐PSA contaminants by silver stain and mass spectrometry.CONCLUSIONSCommercially available preparations of PSA contain contaminating proteins, including trypsin‐like protease activity, that could potentially complicate the interpretation of results obtained from in vitro studies assessing PSA proteolysis of potential protein substrates and effects of PSA on gene expression. Prostate 72:1233–1238, 2012. © 2011 Wiley Periodicals, Inc.
Effects of Short Vacations, Vacation Activities and Experiences on Employee Health and Well‐Being
Authors: de Bloom Jessica , Geurts Sabine A. E. , Kompier Michiel A. J. 
Published: December 2011

AbstractIt was investigated (1) whether employee health and well‐being (H&W) improve during short vacations (4–5 days), (2) how long this improvement lasts after returning home and resuming work and (3) to what extent vacation activities and experiences explain health improvements during and after short vacations.Eighty workers reported their H&W 2 weeks before vacation (Pre), during vacation (Inter), on the day of return (Post 1) and on the third and 10th day after returning home (Post 2 and Post 3, respectively).The results showed improvements in H&W during short vacations (d = 0.62), although this effect faded out rather quickly. Partial correlations and regression analyses showed that employees reported higher H&W during vacation, the more relaxed and psychologically detached they felt, the more time they spent on conversations with the partner, the more pleasure they derived from their vacation activities and the lower the number of negative incidents during vacation. Experiences of relaxation and detachment from work positively influenced H&W even after returning home. Working during vacation negatively influenced H&W after vacation.In conclusion, short vacations are an effective, although not very long lasting, ‘cure’ to improve employees' H&W. Copyright © 2011 John Wiley & Sons, Ltd.
Corporate governance and environmental performance: is there really a link?
Authors: Walls Judith L. , Berrone Pascual , Phan Phillip H. 
Published: December 2011

AbstractCorporate governance scholars are increasingly interested in firms' social and environmental performance. Empirical research in this area, however, has moved forward in an uncoordinated fashion, producing fragmented and contradictory results. Our paper seeks to address this situation by adopting a fact‐based research approach that comprehensively explores the link between corporate governance and environmental performance. Specifically, we aim to understand how the relationships between and among the firms' owners, managers, and boards of directors influence environmental performance. We are particularly interested in understanding the interactions among these three key sets of actors. In the end, we offer some observations about governance practices and discuss the implications for theory. Copyright © 2012 John Wiley & Sons, Ltd.