bluuebunny/crossref_metadata_2025_split huggingface dataset:
C-Reactive Protein Concentrations Are Very High and More Stable over Time Than the Traditional Vascular Risk Factors Total Cholesterol and Systolic Blood Pressure in an Australian Aboriginal Cohort
Authors: Shemesh Tomer , Rowley Kevin G , Jenkins Alicia J , Best James D , O'Dea Kerin 
Published: December 2008

AbstractBackground: Stability of circulating high-sensitivity C-reactive protein (hsCRP) concentrations has implications for its utility in assessing cardiovascular disease (CVD) risk. We sought to determine hsCRP reproducibility in an indigenous Australian cohort with a view to use hsCRP as a marker of future CVD in community-based risk-factor screenings.Methods: Seventy people living in a community on the northern coast of Australia participated in 2 risk-factor screenings over a median (interquartile range) follow-up time of 829 (814–1001) days. hsCRP was measured by high-sensitivity nephelometry.Results: Geometric mean hsCRP concentrations at baseline and follow-up were 4.5 and 5.1 mg/L, respectively (P = 0.220), and Pearson product-moment correlation was 0.775. The proportion of people at high CVD risk (hsCRP &gt;3.0 mg/L) at baseline was 67.1% and remained consistently high (68.6%) at follow-up. Linear regression analysis for follow-up hsCRP as a function of baseline hsCRP, sex, and differences in total and regional body fatness showed that baseline hsCRP was the single predictor in the model, accounting for 63.9% of the total variance in follow-up hsCRP (Pmodel &lt; 0.001). Prevalence agreement (95% CI) between baseline and follow-up for the hsCRP &gt;3.0 mg/L category was 84% (73%–92%) (PMcNemar = not significant), and κ coefficient was fair (0.64, compared with 0.31 for systolic blood pressure ≥140 mmHg and 0.43 for total cholesterol ≥5.5 mmol/L).Conclusions: hsCRP concentrations remained consistently reproducible over time across a wide concentration range in an Aboriginal cohort. Correlations between concentrations over time were better than for other traditional CVD risk factors. hsCRP concentration has potential as a marker of future CVD risk.
Oxidized LDL Receptor LOX-1 Binds to C-Reactive Protein and Mediates Its Vascular Effects
Authors: Fujita Yoshiko , Kakino Akemi , Nishimichi Norihisa , Yamaguchi Saburo , Sato Yuko , Machida Sachiko , Cominacini Luciano , Delneste Yves , Matsuda Haruo , Sawamura Tatsuya 
Published: December 2008

AbstractBackground: C-reactive protein (CRP) exerts biological activity on vascular endothelial cells. This activity may promote atherothrombosis, but the effects of this activity are still controversial. Lectin-like oxidized LDL receptor-1 (LOX-1), the oxidized LDL receptor on endothelial cells, is involved in endothelial dysfunction induced by oxidized LDL.methods: We used laser confocal microscopy to examine and fluorescence cell image analysis to quantify the binding of fluorescently labeled CRP to cells expressing LOX-1. We then examined the binding of unlabeled CRP to recombinant human LOX-1 in a cell-free system. Small interfering RNAs (siRNAs) against LOX-1 were applied to cultured bovine endothelial cells to analyze the role of LOX-1 in native cells. To observe its in vivo effects, we injected CRP intradermally in stroke-prone spontaneously hypertensive (SHR-SP) rats and analyzed vascular permeability.results: CRP bound to LOX-1–expressing cells in parallel with the induction of LOX-1 expression. CRP dose-dependently bound to the cell line and recombinant LOX-1, with significant binding detected at 0.3 mg/L CRP concentration. The Kd value of the binding was calculated to be 1.6 × 10–7 mol/L. siRNA against LOX-1 significantly inhibited the binding of fluorescently labeled CRP to the endothelial cells, whereas control RNA did not. In vivo, intradermal injection of CRP-induced vascular exudation of Evans blue dye in SHR-SP rats, in which expression of LOX-1 is greatly enhanced. Anti–LOX-1 antibody significantly suppressed vascular permeability.Conclusions: CRP and oxidized LDL-receptor LOX-1 directly interact with each other. Two risk factors for ischemic heart diseases, CRP and oxidized LDL, share a common molecule, LOX-1, as their receptor.
Accessing Time–Varying Forces on the Vibrating Tip of the Dynamic Atomic Force Microscope to Map Material Composition
Authors: Sahin Ozgur 
Published: December 2008

AbstractIn dynamic atomic force microscopes the primary physical quantities being measured are the amplitude/phase or amplitude/frequency of the vibrating force probe. Topographic images with spatial resolutions down to the atomic scale can be obtained by mapping these measurements across the sample surface under feedback control. During the imaging process the vibrating tip is observing tip–sample interaction potentials (force–distance relationships) at every point on the surface. The interaction potential is a superposition of short‐ and long–distance interactions of various origins determined by the material compositions of the tip, sample, and the medium of imaging. In principle, measurement of tip–sample interaction potential should allow determination and mapping of material composition of the sample. However, a single measurement of amplitude/phase or amplitude/frequency in dynamic atomic force microscopes is not enough to characterize a complicated tip–sample interaction potential. Recent developments in the understanding of dynamics of the vibrating force probe (cantilever), together with specially designed cantilevers that utilize torsional vibrations in addition to conventional vertical vibrations, enable the recovery of tip–sample interaction potentials at a timescale less than a millisecond. Here, with theory and experiments, we discuss how these cantilevers recover the information about the tip–sample interaction forces and give an example of compositional mapping on a polymeric material system.
Endogenous Fibroblastic Progenitor Cells in the Adult Mouse Lung Are Highly Enriched in the Sca-1 Positive Cell Fraction
Authors: McQualter Jonathan L. , Brouard Nathalie , Williams Brenda , Baird Brandi N. , Sims-Lucas Sunder , Yuen Karen , Nilsson Susan K. , Simmons Paul J. , Bertoncello Ivan 
Published: December 2008

Abstract
Originally identified as a marker specifying murine hematopoietic stem cells, the Sca-1 antigen has since been shown to be differentially expressed by candidate stem cells in tissues including vascular endothelium, skeletal muscle, mammary gland, and prostate of adult mice. In the adult murine lung, Sca-1 has previously been identified as a selectable marker for the isolation of candidate nonhematopoietic (CD45−), nonendothelial (CD31−) bronchioalveolar stem cells (BASC) located at the bronchioalveolar duct junction that coexpress surfactant protein C and the Clara cell specific protein. Our systematic analysis of CD45−CD31−Sca-1+ cells in fetal, neonatal, and adult lung shows that very few of these cells are detectable prior to birth but expand exponentially postnatally coinciding with the transition from the saccular to the alveolar stage of lung development. Unlike candidate BASCs, the CD45−CD31−Sca-1+CD34+ cell fraction we describe coexpresses immunophenotypic markers (Thy-1 and platelet-derived growth factor receptor α) that define lung fibroblastic rather than epithelial cells. The mesenchymal “signature” of the CD45−CD31−Sca-1+CD34+ cell fraction is further confirmed by transcriptional profiling, by cell culture studies demonstrating enrichment for clonogenic lipofibroblastic and nonlipofibroblastic progenitors, and by immunohistochemical localization of Sca-1 in perivascular cells of the lung parenchyma. Although the CD45−CD31−Sca-1+CD34+ cell phenotype does define endogenous clonogenic progenitor cells in the adult murine lung, our data indicate that these progenitors are predominantly representative of mesenchymal cell lineages, and highlights the pressing need for the identification of alternative markers and robust functional assays for the identification and characterization of epithelial and fibroblastic stem and progenitor cell populations in the adult lung.
The role of hydrochlorofluorocarbon densifiers in the formation of clathrate hydrates in deep boreholes and subglacial environments
Authors: Murshed M. Mangir , Faria Sérgio H. , Kuhs Werner F. , Sepp Kipfstuhl  , Wilhelms Frank 
Published: December 2008

AbstractClear evidence for the formation of mixed clathrate hydrates of air and hydrochlorofluorocarbon densifier (known as HCFC-141b, sometimes also called R-141b) is found by means of synchrotron X-ray diffraction and Raman spectroscopy on a sample recovered from the bottom of the EPICA Dronning Maud Land deep borehole in Antarctica. Subglacial water (SGW) appears to have reacted with the drilling liquid to build a large lump of clathrate hydrate. The hydrate growth may well have been accelerated by the stirring of the SGW–densifier mixture during drilling. Moreover, dissolved air in the SGW appears to have participated in the formation of mixed hydrates of air and HCFC-141b as evidenced by the concomitant appearance of Raman signals from both constituents. Our findings elucidate to some extent the meaning of earlier accounts of the formation of ‘heavy chips’ that may sink to the bottom of the borehole, possibly affecting or even impeding the drilling advance. These observations raise concerns with respect to the use of HCFC-141b densifiers in ice-core drilling liquids under warm ice conditions.
The Hans Tausen drill: design, performance, further developments and some lessons learned
Authors: Johnsen Sigfús J. , Hansen Steffen Bo , Sheldon Simon G. , Dahl-Jensen Dorthe , Steffensen Jørgen P. , Augustin Laurent , Journé Paul , Alemany Olivier , Rufli Henry , Schwander Jakob , Azuma Nobuhiko , Motoyama Hideaki , Popp Trevor , Talalay Pavel , Thorsteinsson Thorsteinn , Wilhelms Frank , Zagorodnov Victor 
Published: December 2008

AbstractIn the mid-1990s, excellent results from the GRIP and GISP2 deep drilling projects in Greenland opened up funding for continued ice-coring efforts in Antarctica (EPICA) and Greenland (NorthGRIP). The Glaciology Group of the Niels Bohr Institute, University of Copenhagen, was assigned the task of providing drilling capability for these projects, as it had done for the GRIP project. The group decided to further simplify existing deep drill designs for better reliability and ease of handling. The drill design decided upon was successfully tested on Hans Tausen Ice Cap, Peary Land, Greenland, in 1995. The 5.0m long Hans Tausen (HT) drill was a prototype for the ~11m long EPICA and NorthGRIP versions of the drill which were mechanically identical to the HT drill except for a much longer core barrel and chips chamber. These drills could deliver up to 4m long ice cores after some design improvements had been introduced. The Berkner Island (Antarctica) drill is also an extended HT drill capable of drilling 2 m long cores. The success of the mechanical design of the HT drill is manifested by over 12 km of good-quality ice cores drilled by the HT drill and its derivatives since 1995.
Drilling to the beds of the Greenland and Antarctic ice sheets: a review
Authors: Bentley Charles R. , Koci Bruce R. 
Published: December 2008

AbstractWe give a review of drilling to the beds of the Greenland and Antarctic ice sheets, with a history of just a century. We use a chronological rather than a geographical ordering to emphasize the way drilling has developed. The review is divided into two parts: core drilling and hole-only drilling for access to the beds or the deep interior of the ice sheets. This is an overview, not a comprehensive report on each project. While we have endeavoured to include all projects that fit our selection criteria, we have not provided all the technical details.
Viscosity and density of a two-phase drilling fluid
Authors: Alemany O. , Mityar H. 
Published: December 2008

AbstractMany ice-core drilling projects expect to reach depths greater than 1000 m. At such depths it is necessary to fill the borehole with a fluid to compensate the ice pressure and avoid the resulting significant hole closure. Knowledge of the ice-chips and drilling-fluid circulation parameters (e.g. flow rate, pressure drop, velocity) is essential for understanding the behaviour of the fluid around the drill and will support drill design through a better parameterization in models. A characterization of the dynamic viscosity and of the density of the ice-chips and drilling-fluid mixture is required to calculate these circulation parameters. The goal of this study is to propose a method to calculate, to a first approximation, both these physical properties. The relationships presented here have been established after experimentation, building on prior assumptions taken from the literature.
Dimethyl siloxane oils as an alternative borehole fluid
Authors: Talalay P.G. 
Published: December 2008

AbstractFinding a new safe and ecologically friendly borehole fluid is one of the most pressing problems for forthcoming ice-drilling projects. Not all recent borehole fluids qualify as intelligent choices from safety, environmental and other technological standpoints. We propose the use of silicone oils as the borehole fluid. The most suitable type of silicone oils for deep ice drilling are low-molecular (or volatile) dimethyl siloxane oils (DSOs). Low-molecular DSOs are clear, water-white, tasteless, odorless, neutral liquids. They are hydrophobic and inert substances that are stable to water, air, oxygen, metals, wood, paper, plastics, etc. Of the DSOs, class 2 grades of KF96-1.5cs and KF96-2.0cs most fully fit our criteria for choice as borehole fluids. The final conclusion as to the suitability of DSOs for ice deep drilling will be made after the experiments in a test borehole.
Expression and hypoxic up‐regulation of neuroglobin in human glioblastoma cells
Authors: Emara Marwan , Salloum Nicole , Allalunis-Turner Joan 
Published: December 2008

Neuroglobin is a recently identified globin molecule that is expressed predominantly in the vertebrate brain. Neuroglobin expression increases in oxygen‐deprived neurons, suggesting it protects neurons from ischemic cell death. We report that neuroglobin transcript and protein are expressed in human glioblastoma cells, and that this expression increases in hypoxia in vitro. We also show that neuroglobin is up‐regulated in hypoxic microregions of glioblastoma tumor xenografts. Our finding of hypoxic up‐regulation of neuroglobin in human glioblast	oma cells may provide insight into how tumor cells adapt to and survive in hypoxic microenvironments.
The Arabidopsis Abscisic Acid Catabolic GeneCYP707A2Plays a Key Role in Nitrate Control of Seed Dormancy
Authors: Matakiadis Theodoros , Alboresi Alessandro , Jikumaru Yusuke , Tatematsu Kiyoshi , Pichon Olivier , Renou Jean-Pierre , Kamiya Yuji , Nambara Eiji , Truong Hoai-Nam 
Published: December 2008

AbstractNitrate releases seed dormancy in Arabidopsis (Arabidopsis thaliana) Columbia accession seeds in part by reducing abscisic acid (ABA) levels. Nitrate led to lower levels of ABA in imbibed seeds when included in the germination medium (exogenous nitrate). Nitrate also reduced ABA levels in dry seeds when provided to the mother plant during seed development (endogenous nitrate). Transcript profiling of imbibed seeds treated with or without nitrate revealed that exogenous nitrate led to a higher expression of nitrate-responsive genes, whereas endogenous nitrate led to a profile similar to that of stratified or after-ripened seeds. Profiling experiments indicated that the expression of the ABA catabolic gene CYP707A2 was regulated by exogenous nitrate. The cyp707a2-1 mutant failed to reduce seed ABA levels in response to both endogenous and exogenous nitrate. In contrast, both endogenous and exogenous nitrate reduced ABA levels of the wild-type and cyp707a1-1 mutant seeds. The CYP707A2 mRNA levels in developing siliques were positively correlated with different nitrate doses applied to the mother plants. This was consistent with a role of the CYP707A2 gene in controlling seed ABA levels in response to endogenous nitrate. The cyp707a2-1 mutant was less sensitive to exogenous nitrate for breaking seed dormancy. Altogether, our data underline the central role of the CYP707A2 gene in the nitrate-mediated control of ABA levels during seed development and germination.
Mapping Metabolic and Transcript Temporal Switches during Germination in Rice Highlights Specific Transcription Factors and the Role of RNA Instability in the Germination Process
Authors: Howell Katharine A. , Narsai Reena , Carroll Adam , Ivanova Aneta , Lohse Marc , Usadel Björn , Millar A. Harvey , Whelan James 
Published: December 2008

AbstractTranscriptome and metabolite profiling of rice (Oryza sativa) embryo tissue during a detailed time course formed a foundation for examining transcriptional and posttranscriptional processes during germination. One hour after imbibition (HAI), independent of changes in transcript levels, rapid changes in metabolism occurred, including increases in hexose phosphates, tricarboxylic acid cycle intermediates, and γ-aminobutyric acid. Later changes in the metabolome, including those involved in carbohydrate, amino acid, and cell wall metabolism, appeared to be driven by increases in transcript levels, given that the large group (over 6,000 transcripts) observed to increase from 12 HAI were enriched in metabolic functional categories. Analysis of transcripts encoding proteins located in the organelles of primary metabolism revealed that for the mitochondrial gene set, a greater proportion of transcripts peaked early, at 1 or 3 HAI, compared with the plastid set, and notably, many of these transcripts encoded proteins involved in transport functions. One group of over 2,000 transcripts displayed a unique expression pattern beginning with low levels in dry seeds, followed by a peak in expression levels at 1 or 3 HAI, before markedly declining at later time points. This group was enriched in transcription factors and signal transduction components. A subset of these transiently expressed transcription factors were further interrogated across publicly available rice array data, indicating that some were only expressed during the germination process. Analysis of the 1-kb upstream regions of transcripts displaying similar changes in abundance identified a variety of common sequence motifs, potential binding sites for transcription factors. Additionally, newly synthesized transcripts peaking at 3 HAI displayed a significant enrichment of sequence elements in the 3′ untranslated region that have been previously associated with RNA instability. Overall, these analyses reveal that during rice germination, an immediate change in some metabolite levels is followed by a two-step, large-scale rearrangement of the transcriptome that is mediated by RNA synthesis and degradation and is accompanied by later changes in metabolite levels.
The Acid Growth Theory of auxin-induced cell elongation is alive and well.
Authors: Rayle D L , Cleland R E 
Published: December 2008

Abstract
Plant cells elongate irreversibly only when load-bearing bonds in the walls are cleaved. Auxin causes the elongation of stem and coleoptile cells by promoting wall loosening via cleavage of these bonds. This process may be coupled with the intercalation of new cell wall polymers. Because the primary site of auxin action appears to be the plasma membrane or some intracellular site, and wall loosening is extracellular, there must be communication between the protoplast and the wall. Some "wall-loosening factor" must be exported from auxin-impacted cells, which sets into motion the wall loosening events. About 20 years ago, it was suggested that the wall-loosening factor is hydrogen ions. This idea and subsequent supporting data gave rise to the Acid Growth Theory, which states that when exposed to auxin, susceptible cells excrete protons into the wall (apoplast) at an enhanced rate, resulting in a decrease in apoplastic pH. The lowered wall pH then activates wall-loosening processes, the precise nature of which is unknown. Because exogenous acid causes a transient (1-4 h) increase in growth rate, auxin must also mediate events in addition to wall acidification for growth to continue for an extended period of time. These events may include osmoregulation, cell wall synthesis, and maintenance of the capacity of walls to undergo acid-induced wall loosening. At present, we do not know if these phenomena are tightly coupled to wall acidification or if they are the products of multiple independent signal transduction pathways.
Starch Granule Biosynthesis in Arabidopsis Is Abolished by Removal of All Debranching Enzymes but Restored by the Subsequent Removal of an Endoamylase
Authors: Streb Sebastian , Delatte Thierry , Umhang Martin , Eicke Simona , Schorderet Martine , Reinhardt Didier , Zeeman Samuel C. 
Published: December 2008

Abstract
Several studies have suggested that debranching enzymes (DBEs) are involved in the biosynthesis of amylopectin, the major constituent of starch granules. Our systematic analysis of all DBE mutants of Arabidopsis thaliana demonstrates that when any DBE activity remains, starch granules are still synthesized, albeit with altered amylopectin structure. Quadruple mutants lacking all four DBE proteins (Isoamylase1 [ISA1], ISA2, and ISA3, and Limit-Dextrinase) are devoid of starch granules and instead accumulate highly branched glucans, distinct from amylopectin and from previously described phytoglycogen. A fraction of these glucans are present as discrete, insoluble, nanometer-scale particles, but the structure and properties of this material are radically altered compared with wild-type amylopectin. Superficially, these data support the hypothesis that debranching is required for amylopectin synthesis. However, our analyses show that soluble glucans in the quadruple DBE mutant are degraded by α- and β-amylases during periods of net accumulation, giving rise to maltose and branched malto-oligosaccharides. The additional loss of the chloroplastic α-amylase AMY3 partially reverts the phenotype of the quadruple DBE mutant, restoring starch granule biosynthesis. We propose that DBEs function in normal amylopectin synthesis by promoting amylopectin crystallization but conclude that they are not mandatory for starch granule synthesis.
Modular Spectral Imaging System for Discrimination of Pigments in Cells and Microbial Communities
Authors: Polerecky Lubos , Bissett Andrew , Al-Najjar Mohammad , Faerber Paul , Osmers Harald , Suci Peter A. , Stoodley Paul , de Beer Dirk 
Published: December 2008

ABSTRACT
Here we describe a spectral imaging system for minimally invasive identification, localization, and relative quantification of pigments in cells and microbial communities. The modularity of the system allows pigment detection on spatial scales ranging from the single-cell level to regions whose areas are several tens of square centimeters. For pigment identification in vivo absorption and/or autofluorescence spectra are used as the analytical signals. Along with the hardware, which is easy to transport and simple to assemble and allows rapid measurement, we describe newly developed software that allows highly sensitive and pigment-specific analyses of the hyperspectral data. We also propose and describe a number of applications of the system for microbial ecology, including identification of pigments in living cells and high-spatial-resolution imaging of pigments and the associated phototrophic groups in complex microbial communities, such as photosynthetic endolithic biofilms, microbial mats, and intertidal sediments. This system provides new possibilities for studying the role of spatial organization of microorganisms in the ecological functioning of complex benthic microbial communities or for noninvasively monitoring changes in the spatial organization and/or composition of a microbial community in response to changing environmental factors.