bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of human neutrophil peptides in the initial interaction between lung epithelial cells and CD4+ lymphocytes
Authors: Vaschetto Rosanna , Grinstein Jonathan , Del Sorbo Lorenzo , Khine Aye Aye , Voglis Stefanos , Tullis Elizabeth , Slutsky Arthur S , Zhang Haibo 
Published: January 2007

AbstractHuman neutrophil peptides (HNP) exert immune-modulating effects. We hypothesized that HNP link innate and adaptive immunity through activation of costimulatory molecules. Human lung epithelial cells and CD4+ lymphocytes were treated with HNP separately or in coculture. Stimulation with HNP induced an increase in cell surface expression of CD54 (ICAM-1), CD80, and CD86 on lung epithelial cells and the corresponding major ligands, CD11a (LFA-1), CD152 (CTLA-4), and CD28 on CD4+ lymphocytes. There was an increased nuclear expression of the transcription factor p53 in human alveolar A549 cells and an elevated NF-κB (p50) and a degradation of I-κB protein in CD4+ lymphocytes following HNP stimulation. HNP enhanced the interaction between A549 cells and CD4+ lymphocytes by increasing cell adhesion and release of IFN-γ, IL-2, and IL-8. This was attenuated by using an α1-proteinase inhibitor to neutralize HNP. We conclude that HNP play an important role in linking innate to acquired immunity by activation of costimulatory molecules in lung epithelial cells and CD4+ lymphocytes.
Angiopoietin chemotactic activities on neutrophils are regulated by PI-3K activation
Authors: Brkovic Alexandre , Pelletier Martin , Girard Denis , Sirois Martin G 
Published: January 2007

AbstractAngiopoietins (Ang1 and Ang2) modulate blood vessel integrity during the angiogenic process through the activation of tyrosine kinase receptor (Tie2). We recently detected Tie2 expression on neutrophils and reported that angiopoietins induce acute proinflammatory events including neutrophil β2-integrin activation and their adhesion onto endothelial cells. Herein, we investigated the effect of angiopoietins on neutrophil migration and their capacity to modulate CXCL8/IL-8 chemotactic properties. Using a Boyden chamber assay, we observed that Ang1 and Ang2 (up to 10 nM; 60 min) increased the migration of neutrophils, and the maximal effect was achieved at 1 nM (72% and 114% increase, respectively) as compared with untreated cells. Angiopoietins induce a rapid and transient Akt phosphorylation, and pretreatment of neutrophils with PI-3K inhibitors, wortmannin (100 nM) and LY294002 (500 nM), reduced Ang1-mediated neutrophil migration by 100% and 78% and Ang2 chemotactic activity by 100% and 71%, respectively. Treatment of neutrophils with CXCL8/IL-8 (up to 50 nM; 60 min) increased basal neutrophil migration by 257% at its optimal concentration (10 nM), and pretreatment of neutrophils with corresponding PI-3K inhibitors reduced CXCL8/IL-8 (1 nM) chemotactic effect. Pretreatment of neutrophils with Ang1 or Ang2 (10 nM; 15 min) potentiated neutrophil migration induced by CXCL8/IL-8 (1 or 10 nM; 60 min) by 263% and 238% and by 177% and 164%, respectively. Finally, both angiopoietins showed a synergistic effect on the induction of Akt phosphorylation mediated by CXCL8/IL-8. In summary, our data demonstrate that angiopoietins increase neutrophil migration through PI-3K activation and can enhance proinflammatory activities of other cytokines.
Caring for people with eating disorders: Factors associated with psychological distress and negative caregiving appraisals in carers of people with eating disorders
Authors: Whitney Jenna , Haigh Rachel , Weinman John , Treasure Janet 
Published: January 2007

Objectives Carers of people with eating disorders (ED) have high levels of distress, but little is known about the contributing factors. The aim of this study was to examine predictors of carers' distress and caregiving appraisals using a model of caregiving adapted from the previous literature.Design A cross‐sectional design was used.Methods A sample of 115 individuals currently caring for someone with an ED participated in the study. Carers completed self‐report assessments of psychological distress (GHQ‐12; Goldberg & Williams, 1988), experience of caregiving (Szmukler et al., 1996), illness representations (IPQ‐SCV; Barrowclough, Lobban, Hatton, & Quinn, 2001) and caregiving needs (CaNAM; Haigh & Treasure, 2003). Simple and multiple hierarchical regressions were conducted.Results Approximately 36% (39/109) of carers had scores on the GHQ which indicated mental health difficulties, with 17% (19/109) experiencing high psychological distress. A negative experience of caregiving was associated with carers' distress. The dependency of the individual with the ED and stigma associated with the illness were most highly predictive of carers' distress. Shorter illness duration, higher levels of needs (lower levels of support) and perceptions of high illness consequences contributed to greater negative caregiving appraisals. The belief that the illness was attributable to the sufferers' personality was related to fewer positive appraisals.Conclusions Adjusting to the impact of a family member experiencing an ED is problematic, as suggested by the relationship between shorter illness duration and greater negative appraisals of caregiving. Interventions to help reduce dependency and alleviate stigma may help to decrease carers' distress.
Use of Ecosystem Information to Improve Soil Organic Carbon Mapping of a Mediterranean Island
Authors: D'Acqui Luigi P. , Santi Carolina A. , Maselli Fabio 
Published: January 2007

ABSTRACTDetailed maps of soil C are needed to guide sustainable soil uses and management decisions. The quality of soil C maps of Italian Mediterranean areas may be improved and the sampling density reduced using secondary data related to the nature of the ecosystem. The current study was conducted to determine: (i) the improvements obtainable in mapping soil C over a Mediterranean island by using ecosystem features and (ii) the effect of different sampling densities on the map accuracy. This work relied on field sampling (n= 164) of soil properties measured over the island of Pianosa (Central Italy). Statistical analysis assessing the relationship between soil properties and ecosystem features revealed that the conceptual model of ecosystems defined on the basis of environmental features such as vegetation cover, land use, and soil type was mainly related to the variation of soil organic carbon (OC) content and to the type of Mediterranean environment. The distribution of ecosystems was used to improve the accuracy of soil OC maps obtainable by a simple interpolation approach (ordinary kriging). Substantial improvement was obtained by: (i) stratification into ecosystem types and (ii) applying locally calibrated regressions to satellite imagery that introduced both inter‐ecosystem and intra‐ecosystem information linked to vegetation features. This study showed that interpolation methods using information on ecosystem distribution can produce accurate maps of soil OC in Mediterranean environments, mostly because of the linkage between soil OC and vegetation types, which are spatially fragmented and heterogeneous.
Aerating Grasslands
Authors: Franklin D. H. , Cabrera M. L. , West L. T. , Calvert V. H. , Rema J. A. 
Published: January 2007

ABSTRACTAeration has been promoted as improving infiltration of rainfall and extending grass or forage productivity, but research on the impact of this practice on P losses from grasslands has had mixed results. We designed a study to determine at the field scale, using a paired watershed approach, the impact of slit aeration on runoff volume and P losses in runoff from fescue (Festuca arundinaceaSchreb.)/bermudagrass (Cynodon dactylonL.) hay fields fertilized with broiler litter. Three pairs of 0.8‐ha fields, each with similar soils (Typic Kanhapludults, Aquic Hapludults, and Aquultic Hapludalfs), were fertilized with broiler litter and monitored under similar management from 1995 through 1998, then one field in each pair received aeration treatment from 2001 through 2003. In the field with mostly well‐drained soils, grassland aeration reduced surface runoff volume and mass losses of dissolved reactive P (DRP) in runoff by approximately 35%. In contrast, when poorly drained soils dominated, grassland aeration increased runoff volume (4.8 mm/runoff event) and mass losses of DRP and total P (0.25 kg TP ha−1per runoff event). This implies that aeration of well‐drained soils in the top poultry‐producing counties of Georgia (0.2 million ha) could decrease dissolved phosphorus losses by more than 500 Mg P each year. This is not the case if soils are poorly drained.
Relative Effects of Land Use and Near‐Stream Chemistry on Phosphorus in an Urban Stream
Authors: Sonoda Kazuhiro , Yeakley J. Alan 
Published: January 2007

ABSTRACTElevated levels of P in urban streams can pose significant water quality problems. Sources of P in urban streams, however, are difficult to identify. It is important to recognize both natural and anthropogenic sources of P. We investigated near‐stream chemistry and land use factors on stream water P in the urbanizing Johnson Creek watershed in Portland, OR, USA. We sampled stream water and shallow groundwater soluble reactive P (SRP) and total P (TP) and estimated P flux at 13 sites along the main stem of Johnson Creek, with eight sites in urban land use areas and five sites in nonurban land use areas. At each site, we sampled the A and B horizons, measuring soil pH, water‐soluble P, acid‐soluble P, base‐soluble P, total P, Fe, and Al. We found continuous input of P to the stream water via shallow groundwater throughout the Johnson Creek watershed. The shallow groundwater P concentrations were correlated with stream water P within the nonurban area; however, this correlation was not found in the urban area, suggesting that other factors in the urban area masked the relationship between groundwater P and stream water P. Aluminum and Fe concentrations were inversely correlated with shallow groundwater P, suggesting that greater P adsorption to Al and Fe oxides in the nonurban area reduced availability of shallow groundwater P. Using stepwise multiple regression analysis, however, we concluded that while riparian soil chemistry was related to stream water P, land use patterns had a more significant relationship with stream water P concentrations in this urbanizing system.
Influence of Soil pH and Application Rate on the Oxidation of Calcium Sulfite Derived from Flue Gas Desulfurization
Authors: Lee Y. B. , Bigham J. M. , Dick W. A. , Jones F. S. , Ramsier C. 
Published: January 2007

ABSTRACTCalcium sulfite hemihydrate (CaSO3·0.5H2O), a common byproduct of coal‐fired utilities, is fairly insoluble and can decompose to release toxic SO2under highly acidic soil conditions; however, it can also oxidize to form gypsum. The objective of this study was to examine the effects of application rate and soil pH on the oxidation of calcium sulfite under laboratory conditions. Oxidation rates measured by release of SO4–S to solution decreased with increasing application rate. Leachate SO4–S from soils amended with 1.0 to 3.0 g kg−1CaSO3increased over a 21 to 28 d period before reaching a plateau. At 4 g kg−1, maximum SO4–S release was delayed until Week 7. Oxidation and release of SO4–S from soil amended with 3.0 g kg−1calcium sulfite increased markedly with decreasing soil pH. After only 3 d incubation, the concentrations of SO4–S in aqueous leachates were 77, 122, 170, 220, and 229 mg L−1for initial soil pH values of 7.8, 6.5, 5.5, 5.1, and 4.0, respectively. At an initial soil pH value of 4.0, oxidation/dissolution did not increase much after 3 d. At higher pH values, oxidation was maximized after 21 d. These results suggest that autumn surface applications of calcium sulfite in no‐till systems should permit ample time for oxidation/dissolution reactions to occur without introducing biocidal effects related to oxygen scavenging. Soil and annual crops can thus benefit from additions of soluble Ca and SO4if calcium sulfite is applied in advance of spring planting.
Surface Seals Reduce 1,3‐Dichloropropene and Chloropicrin Emissions in Field Tests
Authors: Gao Suduan , Trout Thomas J. 
Published: January 2007

ABSTRACTReducing emissions is essential for minimizing the impact of soil fumigation on the environment. Water application to the soil surface (or water seal) has been demonstrated to reduce 1,3‐dichloropropene (1,3‐D) emissions in soil column tests. This study determined the effectiveness of water application to reduce emissions of 1,3‐D and chloropicrin (CP) in comparison to other surface seals under field conditions. In a small‐plot field trial on a Hanford sandy loam soil (coarse‐loamy, mixed, superactive, nonacid, thermic Typic Xerorthents) in the San Joaquin Valley, CA. Telone C35 (61% 1,3‐D and 35% CP) was shank‐applied at a depth of 46 cm at a rate of 610 kg ha−1 Soil surface seal treatments included control (no tarp and no water application), standard high density polyethylene (HDPE) tarp over dry and pre‐irrigated soil, virtually impermeable film (VIF) tarp, initial water application by sprinklers immediately following fumigation, and intermittent water applications after fumigation. The atmospheric emissions and gas‐phase distribution of fumigants in soil profile were monitored for 9 d. Among the surface seals, VIF and HDPE tarp over dry soil resulted in the lowest and the highest total emission losses, respectively. Intermittent water applications reduced 1,3‐D and CP emissions significantly more than HDPE tarp alone. The initial water application also reduced emission peak and delayed emission time. Pre‐irrigated soil plus HDPE tarp reduced fumigant emissions similarly as the intermittent water applications and also yielded the highest surface soil temperature, which may improve overall soil pest control.
Effects of Tree Root‐Derived Substrates and Inorganic Nutrients on Pyrene Mineralization in Rhizosphere and Bulk Soil
Authors: Mueller Kevin E. , Shann Jodi R. 
Published: January 2007

ABSTRACTThis study investigated the effects of organic and inorganic nutrients on the microbial degradation of the common soil contaminant pyrene. The material used in this investigation was collected from potted trees that had been growing for over a year in a soil artificially contaminated with polycyclic aromatic hydrocarbons. Soil was removed from the nonroot (bulk) and root (rhizosphere) zones of these pots and used in mineralization studies that tracked microbial degradation of 14C‐pyrene. The factors influencing degradation in these zones were then tested by amendment with essential inorganic nutrients or with root‐derived materials. As expected, pyrene mineralization was greater in soil removed from the rhizosphere than in bulk soil. The rate of mineralization in rhizosphere soil was inhibited by inorganic nutrient amendment, whereas nutrients stimulated mineralization in the bulk soil. Pyrene mineralization in bulk soil was also increased by the addition of root extracts intended to mimic exudation by living roots. However, amendment with excised fine roots that were allowed to decay over time in soil initially inhibited mineralization. With time, the rate of mineralization increased, eventually exceeding that of unamended bulk soil. Combined, the initial inhibition and subsequent stimulation produced a zero net impact of decaying fine roots on bulk soil mineralization. Our results, in conjunction with known temporal patterns of fine root dynamics in natural systems, support the idea that seasonal variations in nutrient and substrate availability may influence the long‐term effect of plants on organic degradation in soil, possibly reducing or negating the beneficial effects of vegetation that are often observed in short‐term studies.
Influence of Decomposition on Chemical Properties of Plant‐ and Manure‐Derived Dissolved Organic Matter and Sorption to Goethite
Authors: Hunt James F. , Ohno Tsutomu , He Zhongqi , Honeycutt C. Wayne , Dail D. Bryan 
Published: January 2007

ABSTRACTSorption of dissolved organic matter (DOM) plays an important role in maintaining the fertility and quality of soils in agricultural ecosystems. Few studies have examined the effects of decomposition on DOM sorption and chemical characteristics. This study investigated the sorption to goethite (α‐FeOOH) of fresh and decomposed hydrophilic (HPL) and hydrophobic (HPB) DOM fractions extracted from the shoots and roots of crimson clover (Trifolium incarnatum L.), corn (Zea mays L.), soybean [Glycine max (L.) Merr.], hairy vetch (Vicia villosa L.), and dairy and poultry manures. Sorption was positively related to apparent molecular weight (MWAP), aromaticity as measured by absorptivity at 280 nm, and phenolic acid content. A 10‐d laboratory microbial decomposition of the source organic matter generally increased the sorption of the extracted DOM onto goethite. The decomposition effect on sorption was greater for the HPL fractions than for the HPB fractions. There was a decrease in the MWAP values of the DOM samples following sorption to goethite. In many cases the reduction in MWAP was large, indicating a strong preference by goethite for the higher MWAP DOM fractions. The results of this laboratory‐based research demonstrate that microbial processes affect the chemical characteristics of DOM which may affect the distribution of soil organic C pools.
Single‐Element and Competitive Metal Mobility Measured with Column Infiltration and Batch Tests
Authors: Antoniadis Vasileios , McKinley John D. , Zuhairi Wan Y. W. 
Published: January 2007

ABSTRACTThe distribution coefficient, Kd, is often used to quantify heavy metal mobility in soils. Batch sorption or column infiltration tests may be used to measure Kd The latter are closer to natural soil conditions, but are difficult to conduct in clays. This difficulty can be overcome by using a laboratory centrifuge. An acceleration of 2600 gravities was applied to columns of London Clay, an Eocene clay sub‐stratum, and Cu, Ni, and Zn mobility was measured in centrifuge infiltration tests, both as single elements and in dual competition. Single‐element Kd values were also obtained from batch sorption tests, and the results from the two techniques were compared. It was found that Kd values obtained by batch tests vary considerably depending on the metal concentration, while infiltration tests provided a single Kd value for each metal. This was typically in the lower end of the range of the batch test Kd values. For both tests, the order of mobility was Ni > Zn > Cu. Metals became more mobile in competition than when in single‐element systems: Ni Kd decreased 3.3 times and Zn Kd 3.4 times when they competed with Cu, while Cu decreased only 1.2 times when in competition with either Ni or Zn. Our study showed that competitive sorption between metals increases the mobility of those metals less strongly bound more than it increases the mobility of more strongly bound metals.
Denitrification Potential and Organic Matter as Affected by Vegetation Community, Wetland Age, and Plant Introduction in Created Wetlands
Authors: Hernandez Maria E. , Mitsch William J. 
Published: January 2007

ABSTRACTDenitrification potential (DP) and organic matter (OM) in soils were compared in three different vegetation communities—emergent macrophyte, open water, and forested edge—in two 10‐yr‐old created riverine wetlands. Organic matter, cold water‐extractable organic matter (CWEOM), anaerobic mineralizable carbon (AnMC), and DP varied significantly (P< 0.05) among vegetation communities. The surface (0 to 9 cm) soils in the emergent macrophyte community (EMC) showed highest DP (0.07 ± 0.01 mg N h−1kg−1), OM (84.90 ± 5.60 g kg−1), CWEOM (1.12 ± 0.20 g kg−1), and AnMC (1.50 ± 0.10 mg C h−1kg−1). In the deeper layer (9 to 18 cm), DP and CWEOM (0.04 ± 0.01 mg N h−1kg−1and 1.13 ± 0.20 g kg−1, respectively) were significantly higher in the open water community (OWC) than in the emergent macrophyte and forested edge communities. Plant introduction did not affect DP or OM content and characteristics. After 10 yr of wetland development, mean DP increased 25‐fold in the surface layer (from 0.002 to 0.053 mg N h−1kg−1); OM content more than doubled to 90.80 ± 19.22 g kg−1, and CWEOM and HWEOM increased 2.5 and 2.7 times respectively from 1993 (prewetland conditions) to 2004. Humic acids were the most abundant form of OM in 2004 and 1993 samples. Significant (P< 0.05) positive relationships between DP and OM, CWEOM, and AnMC were found in the surface layer; in the 9‐ to 18‐cm layer, significant positive relationships were found between DP and CWEOM and AnMC.
Improving the Accuracy of Sediment‐Associated Constituent Concentrations in Whole Storm Water Samples by Wet‐Sieving
Authors: Selbig William R. , Bannerman Roger , Bowman George 
Published: January 2007

ABSTRACTSand‐sized particles (>63 μm) in whole storm water samples collected from urban runoff have the potential to produce data with substantial bias and/or poor precision both during sample splitting and laboratory analysis. New techniques were evaluated in an effort to overcome some of the limitations associated with sample splitting and analyzing whole storm water samples containing sand‐sized particles. Wet‐sieving separates sand‐sized particles from a whole storm water sample. Once separated, both the sieved solids and the remaining aqueous (water suspension of particles less than 63 μm) samples were analyzed for total recoverable metals using a modification of USEPA Method 200.7. The modified version digests the entire sample, rather than an aliquot, of the sample. Using a total recoverable acid digestion on the entire contents of the sieved solid and aqueous samples improved the accuracy of the derived sediment‐associated constituent concentrations. Concentration values of sieved solid and aqueous samples can later be summed to determine an event mean concentration.
Assessment of Water Quality and Identification of Pollution Sources of Plateau Lakes in Yunnan (China)
Authors: Li Renqiang , Dong Ming , Zhao Yang , Zhang Lili , Cui Qingguo , He Weiming 
Published: January 2007

ABSTRACTThe plateau lakes of Yunnan are important both ecologically and economically in China. Nevertheless, the human impact on water quality in these lakes has become increasingly highlighted. The water quality of 10 plateau lakes was monitored regularly over the period of 2000 through 2004 for 24 parameters. Multivariate statistical techniques, including cluster analysis (CA), factor analysis (FA), and principal component analysis (PCA), were employed to better interpret information about the water quality and its pollution sources. No obvious data reduction from CA/FA was found because three principal components (PCs) needed 14 variables to explain 85.01% of the total variance. However, three latent factors accounted for pollution mainly from the following sources: agricultural activities, residential activities and anthropogenic‐toxic pollution from industrial effluents, or other special activities. Box‐whiskers plots were employed to visually interpret the spatiotemporal variations of water quality variables, which were highly correlated with three PCs. Three types of water quality (i.e., low‐, medium‐, and high‐polluted lakes) were determined through CA based on the similarity of water quality variables. Our results may provide helpful information for the authorities to effectively manage the water quality and make sound policies.