bluuebunny/crossref_metadata_2025 huggingface dataset:
Soil Organic Carbon Stocks in Alaska Estimated with Spatial and Pedon Data
Authors: Bliss Norman B. , Maursetter John
Published: February 2010

Temperatures in high‐latitude ecosystems are increasing faster than the average rate of global warming, which may lead to a positive feedback for climate change by increasing the respiration rates of soil organic C. If a positive feedback is confirmed, soil C will represent a source of greenhouse gases that is not currently considered in international protocols to regulate C emissions. We present new estimates of the stocks of soil organic C in Alaska, calculated by linking spatial and field data developed by the USDA NRCS. The spatial data are from the State Soil Geographic database (STATSGO), and the field and laboratory data are from the National Soil Characterization Database, also known as the pedon database. The new estimates range from 32 to 53 Pg of soil organic C for Alaska, formed by linking the spatial and field data using the attributes of Soil Taxonomy. For modelers, we recommend an estimation method based on taxonomic subgroups with interpolation for missing areas, which yields an estimate of 48 Pg. This is a substantial increase over a magnitude of 13 Pg estimated from only the STATSGO data as originally distributed in 1994, but the increase reflects different estimation methods and is not a measure of the change in C on the landscape. Pedon samples were collected between 1952 and 2002, so the results do not represent a single point in time. The linked databases provide an improved basis for modeling the impacts of climate change on net ecosystem exchange.
Incorporating Spatial Dependence into Estimates of Soil Carbon Contents under Different Land Covers
Authors: Worsham Luke , Markewitz Daniel , Nibbelink Nathan
Published: February 2010

Soil C sequestration is a potential method to reduce increasing atmospheric concentrations of CO2, a greenhouse gas. Soil C represents a significant portion of total C in a landscape, although spatial variation can complicate predictions of soil C contents and its change, particularly for C sequestration projects. Quantifying spatial variability for different landscapes may allow adjustment of sampling intensities to improve estimation efficiency, thus facilitating change detection. This study used semivariogram analysis to quantify spatial autocorrelation of soil C concentrations and contents across distances of 10 to 100 m in two 1‐ha pine, hardwood, and pasture sites in the Georgia Piedmont USA. We hypothesized that land cover could help predict spatial autocorrelation and that spatial dependence would exist at greater distances in pasture than pine or hardwood. Average (±1 SD) major range was smaller for pasture total soil C (65 ± 48 m) than pine (77 ± 31 m) or hardwood (81 ± 25 m), which did not support our hypothesis. Two forested plots demonstrated major ranges of 98.8 m, indicating that spatial dependence probably occurred at a scale greater than our plots. Spatial structure was weak to moderate with nugget/sill ratios > 0.30 in all plots. Average C contents in 0 to 7.5 cm based on 64 point samples per plot were 29.9 ± 0.0, 19.8 ± 1.2, and 19.4 ± 4.0 Mg ha−1 for hardwood, pine, and pasture plots (n = 2), respectively. Kriged predictions estimated average C contents of 29.6 ± 0.4, 20.2 ± 0.9, and 19.5 ± 4.1 Mg ha−1, respectively. Incorporating spatial dependence can limit sampling redundancy and improve precision, but only where spatial structure is sufficiently strong.
A Combined Frequency Domain and Tensiometer Sensor for Determining Soil Water Characteristic Curves
Authors: Sun Yurui , Ren Shujuan , Ren Tusheng , Minasny Budiman
Published: February 2010

There is increasing interest in the development of a technique that can simultaneously measure soil matric potential and water content for rapidly determining a soil water characteristic curve. In this study, we developed a new combined soil water content and potential sensor. The new sensor adapted the stainless steel tube of a conventional water‐filled tensiometer into a single sensing electrode for measuring soil water content. This novel design has the advantage of utilizing the whole length of the tensiometer without adding additional components to the sensor. To verify its feasibility, the sensor was tested on three soils (sand, sandy loam, and clay loam) while they were drying under laboratory conditions to produce the soil water characteristic curves in the matric potential range of 0 to −80 kPa. Water characteristic curves of the three soils were also obtained using standard laboratory techniques (tension table and pressure plate). The results show that water characteristic curves of the three soils from the new sensor are in good agreement with those obtained using the standard methods.
Tillage and Inorganic Nitrogen Source Effects on Nitrous Oxide Emissions from Irrigated Cropping Systems
Authors: Halvorson Ardell D. , Del Grosso Stephen J. , Alluvione Francesco
Published: February 2010

Nitrogen fertilization is essential for optimizing crop yields; however, it increases N2O emissions. The study objective was to compare N2O emissions resulting from application of commercially available enhanced‐efficiency N fertilizers with emissions from conventional dry granular urea in irrigated cropping systems. Nitrous oxide emissions were monitored from corn (Zea mays L.) based rotations receiving fertilizer rates of 246 kg N ha−1 when in corn, 56 kg N ha−1 when in dry bean (Phaseolus vulgaris L.), and 157 kg N ha−1 when in barley (Hordeum vulgare L. ssp. vulgare). Cropping systems included conventional‐till continuous corn (CT‐CC), no‐till continuous corn (NT‐CC), no‐till corn–dry bean (NT‐CDb), and no‐till corn–barley (NT‐CB). In the NT‐CC and CT‐CC systems, a controlled‐release, polymer‐coated urea (ESN) and dry granular urea were compared. In the NT‐CDb and NT‐CB rotations, a stabilized urea source (SuperU) was compared with urea. Nitrous oxide fluxes were measured during two growing seasons using static, vented chambers and a gas chromatograph analyzer. Cumulative growing season N2O emissions from urea and ESN application were not different under CT‐CC, but ESN reduced N2O emissions 49% compared with urea under NT‐CC. Compared with urea, SuperU reduced N2O emissions by 27% in dry bean and 54% in corn in the NT‐CDb rotation and by 19% in barley and 51% in corn in the NT‐CB rotation. This work shows that the use of no‐till and enhanced‐efficiency N fertilizers can potentially reduce N2O emissions from irrigated systems.
Soil Organic Carbon Input from Urban Turfgrasses
Authors: Qian Yaling , Follett Ronald F. , Kimble John M.
Published: February 2010

Turfgrass is a major vegetation type in the urban and suburban environment. Management practices such as species selection, irrigation, and mowing may affect C input and storage in these systems. Research was conducted to determine the rate of soil organic C (SOC) changes, soil C sequestration, and SOC decomposition of fine fescue (Festuca spp.) (rainfed and irrigated), Kentucky bluegrass (Poa pratensis L.) (irrigated), and creeping bentgrass (Agrostis palustris Huds.) (irrigated) using C isotope techniques. We found that 4 yr after establishment, about 17 to 24% of SOC at 0 to 10 cm and 1 to 13% from 10 to 20 cm was derived from turfgrass. Irrigated fine fescue added the most SOC (3.35 Mg C ha−1 yr−1) to the 0‐ to 20‐cm soil profile but also had the highest rate of SOC decomposition (2.61 Mg C ha−1 yr−1). The corresponding additions and decomposition rates for unirrigated fine fescue, Kentucky bluegrass, and creeping bentgrass in the top 20‐cm soil profile were 1.39 and 0.87, 2.05 and 1.73, and 2.28 and 1.50 Mg C ha−1 yr−1, respectively. Irrigation increased both SOC input and decomposition. We found that all turfgrasses exhibited significant C sequestration (0.32–0.78 Mg ha−1 yr−1) during the first 4 yr after turf establishment. The net C sequestration rate was higher, however, for irrigated fine fescue and creeping bentgrass than for Kentucky bluegrass. To evaluate total C balance, additional work is needed to evaluate the total C budget and fluxes of the other greenhouse gases in turfgrass systems.
Achieving Soil Organic Carbon Sequestration with Conservation Agricultural Systems in the Southeastern United States
Authors: Franzluebbers Alan J.
Published: February 2010

Conservation management of degraded land has the potential to build soil fertility, restore soil functions, and mitigate greenhouse gas emissions as a consequence of surface soil organic matter accumulation. Literature from the southeastern United States was reviewed and synthesized to: (i) quantitatively evaluate the magnitude and rate of soil organic C (SOC) sequestration with conservation agricultural management; (ii) evaluate how conservation management affects surface SOC accumulation and its implications on ecosystem services; and (iii) recommend practical soil sampling strategies based on spatial and temporal issues to improve the detection of statistically significant SOC sequestration. Soil organic C sequestration was 0.45 ± 0.04 Mg C ha−1 yr−1 (mean ± standard error, n = 147, 20 ± 1 cm depth, 11 ± 1 yr) with conservation tillage compared with conventional tillage cropland. Establishment of perennial pastures sequestered 0.84 ± 0.11 Mg C ha−1 yr−1 (n = 35, 25 ± 2 cm depth, 17 ± 1 yr). Stratification of SOC with depth was common under conservation agricultural management and appears to be integrally linked to abatement of soil erosion, improvement in water quality, and SOC sequestration. Sampling of conservation management systems should ideally occur repeatedly with time in controlled and replicated experiments, but there is also an urgent need for chronosequence and paired‐field surveys of SOC on working farms in the region to validate and expand the scope of inference of experimental results. Landowners in the southeastern United States have great potential to restore soil fertility and mitigate greenhouse gas emissions with the adoption of and improvement in conservation agricultural systems (e.g., continuous no‐till, high‐residue crop rotations, high organic matter inputs).
On the Significance of Properly Weighting Sorption Data for Least Squares Analysis
Authors: Bolster Carl H. , Tellinghuisen Joel
Published: February 2010

In this study, we examined the role of proper weighting in the least squares (LS) analysis of P sorption data when both the dependent (y) and independent (x) variables contain heteroscedastic errors. We compared parameter estimates and uncertainties obtained with unweighted LS (ULS) regression with those obtained using two different weighted LS (WLS) regression methods. In the first WLS method, we weighted the data by the inverse of the variance in y. In the second WLS method, we included the variance in x when calculating the weights. This method, commonly referred to as the effective variance method, has primarily been applied to data with uncorrelated errors in x and y, conditions not representative of sorption studies where values of y are calculated from measured values of x Therefore, in this study we tested a modified version of the effective weighting function that specifically accounts for correlated errors in x and y. The accuracy of the different weighting methods was assessed using Monte Carlo simulations and high‐replication sorption data obtained for three different soil types. Our findings show that the effective variance weighting method provides superior parameter estimates and uncertainties compared with ULS or traditional WLS methods, although the differences between the weighting methods were not always large enough to be of practical concern. We also found that weighting by the effective variance allowed improved assessments of model fits. Our findings are applicable to sorption studies where the dependent variable is calculated from measured values of the so‐called independent variable
Probabilistic Design of Wind Turbines
Authors: Sørensen John D. , Toft Henrik S.
Published: February 2010

Probabilistic design of wind turbines requires definition of the structural elements to be included in the probabilistic basis: e.g., blades, tower, foundation; identification of important failure modes; careful stochastic modeling of the uncertain parameters; recommendations for target reliability levels and recommendation for consideration of system aspects. The uncertainties are characterized as aleatoric (physical uncertainty) or epistemic (statistical, measurement and model uncertainties). Methods for uncertainty modeling consistent with methods for estimating the reliability are described. It is described how uncertainties in wind turbine design related to computational models, statistical data from test specimens, results from a few full-scale tests and from prototype wind turbines can be accounted for using the Maximum Likelihood Method and a Bayesian approach. Assessment of the optimal reliability level by cost-benefit optimization is illustrated by an offshore wind turbine example. Uncertainty modeling is illustrated by an example where physical, statistical and model uncertainties are estimated.
Text and Structural Data Mining of Influenza Mentions in Web and Social Media
Authors: Corley Courtney D. , Cook Diane J. , Mikler Armin R. , Singh Karan P.
Published: February 2010

Text and structural data mining of web and social media (WSM) provides a novel disease surveillance resource and can identify online communities for targeted public health communications (PHC) to assure wide dissemination of pertinent information. WSM that mention influenza are harvested over a 24-week period, 5 October 2008 to 21 March 2009. Link analysis reveals communities for targeted PHC. Text mining is shown to identify trends in flu posts that correlate to real-world influenza-like illness patient report data. We also bring to bear a graph-based data mining technique to detect anomalies among flu blogs connected by publisher type, links, and user-tags.
Carbon-Based Honeycomb Monoliths for Environmental Gas-Phase Applications
Authors: Moreno-Castilla Carlos , Pérez-Cadenas Agustín  F.
Published: February 2010

Honeycomb monoliths consist of a large number of parallel channels that provide high contact efficiencies between the monolith and gas flow streams. These structures are used as adsorbents or supports for catalysts when large gas volumes are treated, because they offer very low pressure drop, short diffusion lengths and no obstruction by particulate matter. Carbon-based honeycomb monoliths can be integral or carbon-coated ceramic monoliths, and they take advantage of the versatility of the surface area, pore texture and surface chemistry of carbon materials. Here, we review the preparation methods of these monoliths, their characteristics and environmental applications.
Non-Traditional Aromatic Topologies and Biomimetic Assembly Motifs as Components of Functional Pi-Conjugated Oligomers
Authors: Tovar John D. , Diegelmann Stephen R. , Peart Patricia A.
Published: February 2010

This article will highlight our recent work using conjugated oligomers as precursors to electroactive polymer films and self-assembling nanomaterials. One area of investigation has focused on nonbenzenoid aromaticity in the context of charge delocalization in conjugated polymers. In these studies, polymerizable pi-conjugated units were coupled onto unusual aromatic cores such as methano[10]annulene. This article will also show how biologically-inspired assembly of molecularly well-defined oligopeptides that flank pi-conjugated oligomers has resulted in the aqueous construction of 1-dimensional nanomaterials that encourage electronic delocalization among the pi-electron systems.
Synthesis, Structure and Thermal Behavior of Oxalato-Bridged Rb+ and H3O+ Extended Frameworks with Different Dimensionalities
Authors: Kherfi Hamza , Hamadène Malika , Guehria-Laïdoudi Achoura , Dahaoui Slimane , Lecomte Claude
Published: February 2010

Correlative studies of three oxalato-bridged polymers, obtained under hydrothermal conditions for the two isostructural compounds {Rb(HC2O4)(H2C2O4)(H2O)2}∞1, 1, {H3O(HC2O4)(H2C2O4).2H2O}∞1, 2, and by conventional synthetic method for {Rb(HC2O4)}∞3, 3, allowed the identification of H-bond patterns and structural dimensionality. Ferroïc domain structures are confirmed by electric measurements performed on 3. Although 2 resembles one oxalic acid sesquihydrate, its structure determination doesn’t display any kind of disorder and leads to recognition of a supramolecular network identical to hybrid s-block series, where moreover, unusual H3O+ and NH4+ similarity is brought out. Thermal behaviors show that 1D frameworks with extended H-bonds, whether with or without a metal center, have the same stability. Inversely, despite the dimensionalities, the same metallic intermediate and final compounds are obtained for the two Rb+ ferroïc materials.
Colloidal Inorganic Nanocrystal Based Nanocomposites: Functional Materials for Micro and Nanofabrication
Authors: Ingrosso Chiara , Panniello AnnaMaria , Comparelli Roberto , Curri Maria Lucia , Striccoli Marinella
Published: February 2010

The unique size- and shape-dependent electronic properties of nanocrystals (NCs) make them extremely attractive as novel structural building blocks for constructing a new generation of innovative materials and solid-state devices. Recent advances in material chemistry has allowed the synthesis of colloidal NCs with a wide range of compositions, with a precise control on size, shape and uniformity as well as specific surface chemistry. By incorporating such nanostructures in polymers, mesoscopic materials can be achieved and their properties engineered by choosing NCs differing in size and/or composition, properly tuning the interaction between NCs and surrounding environment. In this contribution, different approaches will be presented as effective opportunities for conveying colloidal NC properties to nanocomposite materials for micro and nanofabrication. Patterning of such nanocomposites either by conventional lithographic techniques and emerging patterning tools, such as ink jet printing and nanoimprint lithography, will be illustrated, pointing out their technological impact on developing new optoelectronic and sensing devices.
Polysaccharides Coatings on Medical-Grade PVC: A Probe into Surface Characteristics and the Extent of Bacterial Adhesion
Authors: Asadinezhad Ahmad , Novák Igor , Lehocký Marián , Bílek František , Vesel Alenka , Junkar Ita , Sáha Petr , Popelka Anton
Published: February 2010

Medical-grade polyvinyl chloride was coated by polysaccharides through a novel physicochemical approach. An initial surface activation was performed foremost via diffuse coplanar surface barrier discharge plasma in air at ambient temperature and pressure. Then, radical graft copolymerization of acrylic acid through grafting-from pathway was directed to render a well-defined brush of high density, and finally a chitosan monolayer and chitosan/pectin alternating multilayer were bound onto the functionalized surfaces. Surface characteristics were systematically investigated using several probe techniques. In vitro bacterial adhesion and biofilm formation assays indicated that a single chitosan layer was incapable of hindering the adhesion of a Staphylococcus aureus bacterial strain, while up to 30% reduction was achieved by the chitosan/pectin layered assembly. On the other hand, chitosan and chitosan/pectin multilayer could retard Escherichia coli adhesion by 50% and 20%, respectively. Furthermore, plasma treated and graft copolymerized samples were also found effective to diminish the degree of adherence of Escherichia coli.
Synthesis and Characterization of Novel Inorganic-Organic Hybrid Ru(II) Complexes and Their Application in Selective Hydrogenation
Authors: Warad Ismail , Al-Othman Zeid , Al-Resayes Saud , Al-Deyab Salem S. , Kenawy El-Refaie
Published: February 2010

Novel Ru(II) complex-based hybrid inorganic-organic materials immobilized via a diamine co-ligand site instead of the conventional diphosphine ligand have been prepared. The complexes were prepared by two different methods: sol-gel and surface modification techniques. The structures of the desired materials were deduced by several available physical measurements like elemental analyses, infrared, FAB-MS and 1H-, 13C- and 31P-NMR spectroscopy. Due to a lack of solubility the structures of xerogel 3 and modified 4 were studied by solid state 13C-, 29Si- and 31P-NMR spectroscopy, infrared spectroscopy and EXAFS. These materials were stable enough to serve as hydrogenation catalysts. Selective hydrogenation of functionalized carbonyls in a,b-unsaturated compounds was successfully carried out under mild conditions in a basic medium using these complexes as catalysts.
Escherichia coli Cytotoxic Necrotizing Factor 1 (CNF1): Toxin Biology, in Vivo Applications and Therapeutic Potential
Authors: Fabbri Alessia , Travaglione Sara , Fiorentini Carla
Published: February 2010

CNF1 is a protein toxin produced by certain pathogenic strains of Escherichia coli. It permanently activates the regulatory Rho, Rac, and Cdc42 GTPases in eukaryotic cells, by deamidation of a glutamine residue. This modification promotes new activities in cells, such as gene transcription, cell proliferation and survival. Since the Rho GTPases play a pivotal role also in several processes in vivo, the potentiality of CNF1 to act as a new pharmacological tool has been explored in experimental animals and in diverse pathological contexts. In this review, we give an update overview on the potential in vivo applications of CNF1.
How Flaviviruses Activate and Suppress the Interferon Response
Authors: Muñoz-Jordán Jorge L. , Fredericksen Brenda L.
Published: February 2010

The flavivirus genus includes viruses with a remarkable ability to produce disease on a large scale. The expansion and increased endemicity of dengue and West Nile viruses in the Americas exemplifies their medical and epidemiological importance. The rapid detection of viral infection and induction of the innate antiviral response are crucial to determining the outcome of infection. The intracellular pathogen receptors RIG-I and MDA5 play a central role in detecting flavivirus infections and initiating a robust antiviral response. Yet, these viruses are still capable of producing acute illness in humans. It is now clear that flaviviruses utilize a variety of mechanisms to modulate the interferon response. The non-structural proteins of the various flaviviruses reduce expression of interferon dependent genes by blocking phosphorylation, enhancing degradation or down-regulating expression of major components of the JAK/STAT pathway. Recent studies indicate that interferon modulation is an important factor in the development of severe flaviviral illness. This suggests that an increased understanding of viral-host interactions will facilitate the development of novel therapeutics to treat these viral infections and improved biological models to study flavivirus pathogenesis.
INFLUENCE OF CONSTITUTION OF HYBRID FERROCENYL ALKANETHIOLS SELF-ASSEMBLED MONOLAYERS TO INTERFACIAL CHARACTERISTICS ON GOLD SURFACE
Authors: Huang Jhen-Gang , Lee Adam Shih-Yuan , Chu Shu-Fang , Lin Yun-Han , Lin Chii-Wann
Published: February 2010

The interfacial characteristics of self-assembled monolayer (SAM), that are applied in miniaturized sensor design, were strongly influenced by the SAM constitution. The electrochemical and interfacial characteristics of hybrid SAMs that constituted with ferrocenyl octanethiol ( FcC 8 SH ) and unsubstituted octanethiol ( C 8) or 2-mercaptopyrimidine (2-MPD) were investigated in this study. The peaks of anodic oxidation were observed at around 0.49 V (vs. Ag/AgCl ) in the FcC 8 SH/C 8 hybrid SAM. However, the oxidation potentials descended from 0.42–0.38 V as the molar fraction of FcC 8 SH was decreased from 0.8–0.2 in the FcC 8 SH /2-MPD hybrid SAM. On the other hand, the interfacial hydrophilicity of FcC 8 SH /2-MPD hybrid SAM was measured to be higher than the FcC 8 SH/C 8 hybrid SAM due to the random arrangement of SAM caused by the shape of 2-MPD. Then, the surface roughness of hybrid SAM and chain length of ferrocenyl alkanethiols were all considered to be the parameters of interfacial characteristics.

In summary, doping of 2-MPD in SAMs might reduce the rigidity of ferrocenyl alkanethiol SAMs and increase the interfacial hydrophilicity. This result will be useful in the development of the low power consumption portable bioanalytical system. And a miniaturized bioanalytical system based on ferrocenyl SAMs would be developed in the future.
Depleting Syndecan-4+ T Lymphocytes Using Toxin-Bearing Dendritic Cell-Associated Heparan Sulfate Proteoglycan-Dependent Integrin Ligand: A New Opportunity for Treating Activated T Cell-Driven Disease
Authors: Akiyoshi Hideo , Chung Jin-Sung , Tomihari Mizuki , Cruz Ponciano D. , Ariizumi Kiyoshi
Published: February 2010

Because syndecan-4 (SD-4) is expressed by some (but not all) T cells following activation and serves as the exclusive ligand of dendritic cell-associated heparan sulfate proteoglycan-dependent integrin ligand (DC-HIL), we envisioned the DC-HIL/SD-4 pathway to be a therapeutic target for conditions mediated by selectively activated T cells. We conjugated soluble DC-HIL receptor with the toxin saporin (SAP; DC-HIL-SAP) and showed it to bind activated (but not resting) T cells and become internalized by and deplete SD-4+ T cells. In hapten-sensitized mice, DC-HIL-SAP injected i.v. prior to hapten challenge led to markedly suppressed contact hypersensitivity responses that lasted 3 wk and were restricted to the hapten to which the mice were originally sensitized. Such suppression was not observed when DC-HIL-SAP was applied during sensitization. Moreover, the same infusion of DC-HIL-SAP produced almost complete disappearance of SD-4+ cells in haptenated skin and a 40% reduction of such cells within draining lymph nodes. Our results provide a strong rationale for exploring use of toxin-conjugated DC-HIL to treat activated T cell-driven disease in humans.
Differential Roles of Macrophages in Diverse Phases of Skin Repair
Authors: Lucas Tina , Waisman Ari , Ranjan Rajeev , Roes Jürgen , Krieg Thomas , Müller Werner , Roers Axel , Eming Sabine A.
Published: February 2010

Influx of macrophages plays a crucial role in tissue repair. However, the precise function of macrophages during the healing response has remained a subject of debate due to their functional dichotomy as effectors of both tissue injury and repair. We tested the hypothesis that macrophages recruited during the diverse phases of skin repair after mechanical injury exert specific functions to restore tissue integrity. For this purpose, we developed a mouse model that allows conditional depletion of macrophages during the sequential stages of the repair response. Depletion of macrophages restricted to the early stage of the repair response (inflammatory phase) significantly reduced the formation of vascularized granulation tissue, impaired epithelialization, and resulted in minimized scar formation. In contrast, depletion of macrophages restricted to the consecutive mid-stage of the repair response (phase of tissue formation) resulted in severe hemorrhage in the wound tissue. Under these conditions, transition into the subsequent phase of tissue maturation and wound closure did not occur. Finally, macrophage depletion restricted to the late stage of repair (phase of tissue maturation) did not significantly impact the outcome of the repair response. These results demonstrate that macrophages exert distinct functions during the diverse phases of skin repair, which are crucial to control the natural sequence of repair events.
Cytomegalovirus Infection Reduces Telomere Length of the Circulating T Cell Pool
Authors: van de Berg Pablo J. E. J. , Griffiths Stephen J. , Yong Si-La , Macaulay Richard , Bemelman Frederike J. , Jackson Sarah , Henson Sian M. , ten Berge Ineke J. M. , Akbar Arne N. , van Lier René A. W.
Published: February 2010

Short telomeres of circulating leukocytes are a risk factor for age-related diseases, such as atherosclerosis, but the exact mechanisms generating variations in telomere length are unknown. We hypothesized that induction of differentiated T cells during chronic CMV infection would affect T cell telomere length. To test this, we measured the amount of differentiated T cells and telomere length of lymphocytes during primary CMV infection as well as CMV-seropositive and -seronegative healthy individuals. After primary CMV infection, we observed an increase in highly differentiated cells that coincided with a steep drop in telomere length. Moreover, we found in a cohort of 159 healthy individuals that telomere shortening was more rapid in CMV-seropositive individuals and correlated with the amount of differentiated T cells in both CD4+ T cells and CD8+ T cells. Finally, we found that telomere length measured in blood leukocytes is correlated with lymphocyte telomere length. Thus, CMV infection induces a strong decrease in T cell telomere length, which can be explained by changes in the composition of the circulating lymphocyte pool.
Reactive Oxygen Species Level Defines Two Functionally Distinctive Stages of Inflammatory Dendritic Cell Development from Mouse Bone Marrow
Authors: Sheng Kuo-Ching , Pietersz Geoffrey A. , Tang Choon Kit , Ramsland Paul A. , Apostolopoulos Vasso
Published: February 2010

Reactive oxygen species (ROS) have been implicated in various physiological activities. However, their role in dendritic cell (DC) activation and generation has not been investigated. Using the bone marrow-derived GM-CSF–induced ex vivo DC model, we characterize how induction of ROS correlates with inflammatory DC functionality and expansion. We describe that the functionality of GM-CSF–induced DCs is distinct in two developmental stages. Whereas division of DC-committed hematopoietic progenitor cells (HPCs) neared completion by day 6, the level of ROS soared after day 4. Day 3 ROSlo DCs were highly responsive to TLR stimuli such as LPS and zymosan by rapid upregulation of CD80, CD86, and MHC class II, in contrast to the low response of day 6 ROShi DCs. ROShi DCs could not initiate and sustain a significant level of NF-κB phosphorylation in response to LPS and zymosan, although demonstrating hyperactivation of p38 MAPK by LPS, in a fashion disparate to ROSlo DCs. ROSlo DCs stimulated a higher level of allogeneic and OVA-specific T cell proliferative responses, although ROShi DCs were much more proficient in processing OVA. In response to pathogenic stimuli, ROShi DCs also demonstrated rapid cellular adhesion and H2O2 release, indicating their role in immediate microbial targeting. Moreover, HPC expansion and DC generation were dependent on the surge of ROS in an NADPH oxidase-independent manner. These findings point to the potential role of cellular ROS in mediating functionality and development of DCs from HPCs during inflammation.
The nerve of osteoarthritis pain
Authors: Hochman Jacqueline R. , French Melissa R. , Bermingham Sarah L. , Hawker Gillian A.
Published: February 2010

Objective

Cumulative data suggest that central sensitization may contribute to pain in osteoarthritis (OA) and present with symptoms typically associated with neuropathic pain (NP). We evaluated the responses from focus group participants on the knee OA pain experience for pain descriptions that suggest NP.

Methods

Focus group transcripts were analyzed by 2 independent assessors for unprompted use of pain descriptors that suggested NP. Items from validated NP symptom‐based questionnaires were used to guide the analysis. Data on sociodemographic factors, duration of knee OA, and OA disease and pain severity (using the Western Ontario and McMaster Universities Osteoarthritis Index and a numerical rating scale) were obtained from questionnaires administered after focus group completion. These factors were compared among participants who did and did not use descriptors that suggested NP.

Results

Transcripts from 80 knee OA participants were analyzed. A range of NP descriptors was used to characterize their knee symptoms, including burning, tingling, numbness, and pins and needles. The proportion of participants who used NP descriptors was 0.34 (95% confidence interval 0.24–0.45). Those who used NP descriptors were younger (P = 0.003) and, although not statistically different, more likely to be women, with higher pain intensity and OA severity and longer OA duration, than those who did not use NP descriptors.

Conclusion

During focus groups, a subset of adults with chronic, symptomatic knee OA used pain quality descriptors that were suggestive of NP. Elicitation of NP descriptors in people with OA may help identify those who could benefit from further evaluation and perhaps treatment for NP.
Axillary node staging by ultrasonography and fine-needle aspiration cytology in patients with breast cancer
Authors: Baruah B P , Goyal A , Young P , Douglas-Jones A G , Mansel R E
Published: February 2010

Background

This study evaluated the role of axillary ultrasonography (AUS) and fine-needle aspiration cytology (FNAC) in preoperative staging of the axilla in patients with invasive breast cancer.

Methods

Between October 2006 and March 2009, 502 patients scheduled to undergo surgery for invasive breast cancer had preoperative AUS. All patients with suspicious nodes on ultrasonography underwent FNAC, and those with positive cytology proceeded directly to axillary node clearance. Patients with normal findings on AUS or negative cytology underwent sentinel node biopsy (SNB).

Results

A total of 137 (27·3 per cent) of 502 patients had axillary node metastases on final histology. Thirty-nine (28·5 per cent) node-positive patients were identified by AUS–FNAC and spared unnecessary SNB. AUS–FNAC had a sensitivity of 28·5 per cent and a specificity of 100 per cent for detecting axillary nodal metastases. AUS–FNAC findings were normal in all 15 patients with nodal micrometastases and in 11 patients with isolated tumour cells on histopathology. The sensitivity of AUS–FNAC had a positive correlation with invasive tumour size (odds ratio 1·03) and grade (odds ratio 2·80).

Conclusion

Preoperative AUS–FNAC avoided unnecessary SNB in 28·5 per cent of node-positive patients and in 7·8 per cent of patients overall.
Preventive role of PD‐1 on MPTP‐induced dopamine depletion in mice
Authors: Jung Hyo Won , Son Hye Young , Jin Guang‐Zhen , Park Yong‐Ki
Published: February 2010

Many current studies of Parkinson's disease (PD) suggest that inflammation is involved in the neurodegenerative process. PD‐1, a traditional Korean medicine, used to treat various brain diseases in Korea. This study was designed to investigate the effect of PD‐1 extract in the Parkinson's model of 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP) lesioned mice. The MPTP administration caused the dopamine neuron loss in the striatum and substantia nigra pars compacta (SNpc), which was demonstrated by a depletion of tyrosine hydroxylase (TH). In addition, a reduction of bcl‐2 expression with elevation of bax expression, caspase‐3 activation, and release of cytochrome c into cytosol in dopaminergic neurons of SNpc were noted. Oral administration of PD‐1 extract (50 and 100 mg kg−1) attenuated the MPTP‐induced depletion of TH proteins in the striatum and SNpc and prevented the apoptotic effects. These results indicate that PD‐1 extract is able to protect dopaminergic neurons from MPTP‐induced neuronal death, with important implications for the treatment of PD. Copyright © 2010 John Wiley & Sons, Ltd.
Stent graft exclusion of a pseudoaneurysm in a Blalock‐Taussig shunt
Authors: Sanchez‐Recalde Angel , Garzón Gonzalo , Oliver José M.
Published: February 2010

This case is the first report of slow‐growing pseudoaneurysm after vessel dissection secondary to two stents implantation into classic Blalock Taussig shunt in a patient with pulmonary atresia and ventricular septal defect. Pseudoaneurysm was successfully excluded by a percutaneous approach with self‐expandable stent graft deployment from the aorta to the middle of the Blalock Taussig shunt. Nearly 3 years after the procedure, the classic BT is patent, and there were no restenosis or thrombosis in spite of the very long length of the stented segment. © 2010 Wiley‐Liss, Inc.
Temporal Trends in the Use of Drug‐eluting Stents for Approved and Off‐label Indications: A Longitudinal Analysis of a Large Multicenter Percutaneous Coronary Intervention Registry
Authors: Gualano Sarah K. , Gurm Hitinder S. , Share David , Smith Dean , Aronow Herbert D. , LaLonde Thomas , Bates Eric R , Changezi Hameem , McNamara Richard , Moscucci Mauro
Published: February 2010

Background

We sought to examine the temporal variations in the rate of both bare‐metal stent (BMS) and drug‐eluting stent (DES) use for off‐label indications after the reports of an increased risk of very late stent thrombosis in patients with DES at the 2006 meeting of the European Society of Cardiology (ESC).

Hypothesis

To determine whether the decrease in use of DES has affected both on and off‐label indications.

Methods

The study cohort included patients undergoing coronary intervention in a large regional registry, the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2). Patient demographic and clinical characteristics for patients with DES in the third quarter of 2006 (pre‐ESC) were compared to those from the fourth quarter of 2008 (post‐guideline changes). Use of DES for off‐label indications, such as ST‐segment elevation myocardial infarction (STEMI), in‐stent restenosis (ISR), and saphenous vein graft (SVG) interventions, were evaluated.

Results

The overall deployment of DES fell sharply from 83% pre‐ESC to a plateau of 58% in the first quarter of 2008. This corresponded to a rise in BMS use, while angioplasty procedures stayed the same. The STEMI subgroup showed the most dramatic change, from 78% to only 36%. Off‐label use in SVGs showed a similar trend, from 74% to 43%. Drug‐eluting stent deployment for ISR was less affected, though it also fell 25% (from 79%–56%).

Conclusions

The use of DES has fallen dramatically from June 2006 to December 2008, particularly for nonapproved indications. Our study provides a real‐world assessment of contemporary change in DES use in response to the presentation of negative observational studies. Copyright © 2010 Wiley Periodicals, Inc.
Synthesis and Biological Evaluation of 9‐Oxo‐9H‐indeno[1,2‐b]pyrazine‐2,3‐dicarbonitrile Analogues as Potential Inhibitors of Deubiquitinating Enzymes
Authors: Colombo Matteo , Vallese Stefania , Peretto Ilaria , Jacq Xavier , Rain Jean‐Christophe , Colland Frédéric , Guedat Philippe
Published: February 2010

High‐throughput screening highlighted 9‐oxo‐9H‐indeno[1,2‐b]pyrazine‐2,3‐dicarbonitrile (1) as an active inhibitor of ubiquitin‐specific proteases (USPs), a family of hydrolytic enzymes involved in the removal of ubiquitin from protein substrates. The chemical behavior of compound 1 was examined. Moreover, the synthesis and in vitro evaluation of new compounds, analogues of 1, led to the identification of potent and selective inhibitors of the deubiquitinating enzyme USP8.
Increase in post‐dialysis hemoglobin can be out of proportion and unrelated to ultrafiltration
Authors: Geller Ari B. , DeVita Maria V. , Marku‐Podvorica Jehona , Rosenstock Jordan L. , Panagopoulos Georgia , Michelis Michael F.
Published: February 2010

OBJECTIVE

The objective of this study was to compare pre‐dialysis and post‐dialysis hemoglobin (Hgb) and ultrafiltration in hemodialysis patients. Factors influencing Hgb are not well understood.

METHODS

Pre‐dialysis and post‐dialysis Hgb and weight were measured in 133 hemodialysis patients. Absolute and percentage change in Hgb (%ΔHgb) and percent change in body weight (%ΔBW) were determined for that treatment. Patients were divided into 2 groups, those with post‐dialysis Hgb < 13 g/dL (group 1) and those with post‐dialysis Hgb ≥13 g/dL (group 2); the differences in %ΔBW were compared between the 2 groups.

RESULTS

The mean pre‐dialysis Hgb was 11.9 ± 1.4 g/dL, the mean post‐dialysis Hgb level was 12.8 ± 1.8 g/dL. The %ΔHgb was 3.9 ± 6.6 in group 1 and 10.8 ± 7.8 in group 2. The %ΔBW was 3.1 ± 1.4 in group 1 and 3.9 ± 1.7 in group 2 (p < .001 for all comparisons). We found that although both groups had a rise in Hgb level post‐dialysis, group 2 patients had a rise in %ΔHgb that was greater than the relatively small difference in %ΔBW between the 2 groups. In addition, we found only a modest correlation between %ΔBW and %ΔHgb in both groups. The r2 of 0.24 suggests that only 25% of the variability found in %ΔHgb can be related to %ΔBW.

CONCLUSIONS

Patients with post‐dialysis Hgb ≥13 g/dL had a greater increase in %ΔHgb that was out of proportion to %ΔBW. Factors other than %ΔBW may play a role in determining post‐dialysis Hgb.
A genetic variation in the fat mass‐ and obesity‐associated gene is associated with obesity and newly diagnosed type 2 diabetes in a Chinese population
Authors: Li Xiangyang , Song Fangfang , Jiang Hong , Zhang Muxun , Lin Jie , Bao Wei , Yao Ping , Yang Xuefeng , Hao Liping , Liu Liegang
Published: February 2010

Background

Recently, a genome‐wide association study identified a strong association between the fat mass‐ and obesity‐associated rs9939609 single nucleotide polymorphism (SNP) and the risk of obesity in European population. However, the results in Chinese population were reported to be contradictory. Therefore, our aim was to examine whether this SNP is associated with obesity and newly diagnosed type 2 diabetes (T2D) in Chinese population.

Methods

We genotyped rs9939609 in 2587 subjects [obesity 243, overweight 976, normal weight 1368 or newly diagnosed T2D 877, impaired glucose regulation 305, normal glucose tolerance (NGT) 1405] using an allelic discrimination assay‐by‐design TaqMan method on ABI7900HT. We analysed associations of the rs9939609 SNP with obesity and newly diagnosed T2D through Logistic regression analysis.

Results

In obesity case–control study, we found that the A allele was strongly associated with obesity and overweight. The odds ratios for the allele A versus T were 1.447 for Obesity versus normal weight (95% CI 1.104–1.896, p = 0.007) and 1.363 for Overweight versus normal weight (95% CI 1.149–1.617, p < 0.0001). In T2D case–control study, the odds ratios for the allele A versus T were 1.305 for T2D versus NGT (95% CI 1.097–1.552, p = 0.003) and 1.280 for combined T2D and impaired glucose regulation (IGR) versus NGT (95% CI 1.089–1.503, p = 0.003). The associations of the A allele with T2D and combined T2D and IGR remained significant with adjustment for age, sex and body mass index (BMI).

Conclusion

The fat mass‐ and obesity‐associated gene rs9939609 SNP is strongly associated with risk of obesity and newly diagnosed T2D in the Chinese population. Copyright © 2010 John Wiley & Sons, Ltd.
Caenorhabditis elegans: A new model organism for studies of axon regeneration
Authors: Ghosh‐Roy Anindya , Chisholm Andrew D.
Published: February 2010

Axonal regeneration in Caenorhabditis elegans was first reported five years ago. Individual green fluorescent protein‐labeled axons can be severed using laser microsurgery and their regrowth followed in vivo. Several neuron types display robust regrowth after injury, including motor and sensory neurons. The small size and transparency of C. elegans make possible large‐scale genetic and pharmacological screens for regeneration phenotypes. Developmental Dynamics 239:1460–1464, 2010. © 2010 Wiley‐Liss, Inc.
Efficient transposition of a single Minos transposon copy in the genome of the ascidian Ciona intestinalis with a transgenic line expressing transposase in eggs
Authors: Hozumi Akiko , Kawai Narudo , Yoshida Reiko , Ogura Yosuke , Ohta Naoyuki , Satake Honoo , Satoh Nori , Sasakura Yasunori
Published: February 2010

Transgenesis with transposons is an important technique for studying genetic functions. In the ascidian Ciona intestinalis, methods for germline transformation with the Tc1/mariner transposon Minos have been established. A system to remobilize a single Minos copy in the genome is needed to refine this transgenic technique. In this study, such an experimental system was established with a transgenic line expressing Minos transposase in eggs. In the eggs of a double transgenic animal from a cross between the egg transposase line and a transgenic line having a single Minos insertion, the transposon was transposed into new positions of the Ciona genome, thus creating new insertions. Some of the new insertions caused enhancer detection. The majority of the new insertion sites were mapped on different chromosomes from that of the transposon donor. This characteristic of Minos is in contrast to that of the Sleeping Beauty transposon, which causes frequent intrachromosomal transposition. Developmental Dynamics 239:1076–1088, 2010. © 2010 Wiley‐Liss, Inc.
Dynamic Approaches towards Catalyst Discovery
Authors: Gasparini Giulio , Dal Molin Marta , Prins Leonard J.
Published: February 2010

Catalyst development is a challenging task, caused by the subtle effects that determine whether a catalyst is efficient or not. Success is enhanced by using methodology that relies to a smaller extent on rational design. Combinatorial high‐throughput approaches allow for a systematic exploration of chemical space, but require an easy synthetic access to structurally diverse catalysts. The use of dynamic or reversible chemistry for the construction of catalysts is an attractive option as it allows for self‐assembly and self‐selection processes. Synthesis is restricted to the building blocks after which diversity is simply generated upon mixing. Self‐selection of the best catalyst by the target reaction relieves the burden of rational design. Molecular systems exhibiting catalysis as an emerging property due to a cooperative interplay of the molecular components are envisioned for the future.
Erythrocytes serve as a reservoir for cellular and extracellular sphingosine 1‐phosphate
Authors: Bode Constantin , Sensken Sven‐Christian , Peest Ulrike , Beutel Gernot , Thol Felicitas , Levkau Bodo , Li Zaiguo , Bittman Robert , Huang Tao , Tölle Markus , van der Giet Markus , Gräler Markus H.
Published: February 2010

Sphingosine 1‐phosphate (S1P) in blood is phosphorylated, stored, and transported by red blood cells (RBC). Release of S1P from RBC into plasma is a regulated process that does not occur in plasma‐ or serum‐free media. Plasma fractionation and incubations with isolated and recombinant proteins identified high density lipoprotein (HDL) and serum albumin (SA) as non‐redundant endogenous triggers for S1P release from RBC. S1P bound to SA and HDL was able to stimulate the S1P1 receptor in calcium flux experiments. The binding capability of acceptor molecules triggers S1P release, as demonstrated with the anti‐S1P antibody Sphingomab™. More S1P was extracted from RBC membranes by HDL than by SA. Blood samples from anemic patients confirmed a reduced capacity for S1P release in plasma. In co‐cultures of RBC and endothelial cells (EC), we observed transcellular transportation of S1P as a second function of RBC‐associated S1P in the absence of SA and HDL and during tight RBC‐EC contact, mimicking conditions in tissue interstitium and capillaries. In contrast to S1P bound to SA and HDL, RBC‐associated S1P was significantly incorporated by EC after S1P lyase (SGPL1) inhibition. RBC‐associated S1P, therefore, has two functions: (1) It contributes to the cellular pool of SGPL1‐sensitive S1P in tissues after transcellular transportation and (2) it helps maintain extracellular S1P levels via SA and HDL independently from SGPL1 activity. J. Cell. Biochem. 109: 1232–1243, 2010. © 2010 Wiley‐Liss, Inc.