bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular docking and comparative molecular similarity indices analysis of estrogenicity of polybrominated diphenyl ethers and their analogues
Authors: Yang Weihua , Liu Xiaohua , Liu Hongling , Wu Yang , Giesy John P. , Yu Hongxia 
Published: March 2010

Abstract
Molecular docking and three-dimensional quantitative structure–activity relationships (3D-QSAR) were used to develop models to predict estrogenicity of polybrominated diphenyl ethers (PBDEs), para-hydroxylated polybrominated diphenyl ethers (para-HO-PBDEs), and brominated bisphenol A compounds to the human estrogen receptor α (hERα). Based on the molecular conformations developed from the molecular docking, predictive comparative molecular similarity indices analysis (CoMSIA) models were developed. The results of CoMSIA modeling with region focusing included were: leave-one-out (LOO) cross-validated coefficient q2(LOO) = 0.722 (all 26 compounds), q2(LOO) = 0.633 (the training set, 20 compounds), q2(LMO, two groups) = 0.520 ± 0.155 (26 compounds), q2(LMO, five groups) = 0.665 ± 0.068 (26 compounds), predictive r2, r2pred = 0.686 (the test set, 6 compounds), and Q2EXT = 0.678. The 3D-QSAR can be used to infer the activities of compounds with similar structural characteristics. The interaction mechanism between compounds and the hERα was explored. Hydrogen bonding of the compound with Glu353 in the hERα is an important determinant of the estrogenic activity of para-HO-PBDEs and brominated bisphenol A. Environ. Toxicol. Chem. 2010;29:660–668. © 2009 SETAC
Evaluation of the amphibian metamorphosis assay: Exposure to the goitrogen methimazole and the endogenous thyroid hormone L-thyroxine
Authors: Coady Katherine , Marino Troy , Thomas Johnson , Currie Rebecca , Hancock Gregg , Crofoot Jackie , McNalley Lindsay , McFadden Lisa , Geter David , Klecka Gary 
Published: March 2010

Abstract
The U.S. Environmental Protection Agency (U.S. EPA) has included an amphibian metamorphosis assay (AMA) to detect thyroid active chemicals in Tier 1 testing of their endocrine screening program. To understand the variability, specificity, and reliability of the key endpoints of this assay, two exposure studies with Xenopus laevis tadpoles were conducted with two known thyroid-active compounds, namely, methimazole or L-thyroxine, for a total of 21 d. In addition, various increased-flow-rate treatments were included in the exposures to evaluate the effects of physical stress on metamorphic development. The endpoints examined in the exposures were wet weight, snout–vent length, hind-limb length, developmental stage, and thyroid and gonadal histopathology. As expected, the results indicated that both methimazole and L-thyroxine were thyroid active in the AMA, hind-limb length and thyroid histopathology being the most sensitive endpoints of thyroid activity. Tadpoles that were exposed to the various physical stressors in these experiments showed no signs of altered metamorphic development, and exposure to the thyroid-active compounds had no effect on the developing gonad of X. laevis. Taken together, these results support the use of the AMA as a Tier 1 endocrine screen for detection of potential thyroid pathway activity; however, the lack of a true negative response (no-effect) during the validation process prevents a full evaluation of this assay's specificity at this time. Environ. Toxicol. Chem. 2010;29:869–880. © 2009 SETAC
Influence of deltamethrin on nonspecific cellular and humoral defense mechanisms in rainbow trout (Oncorhynchus mykiss)
Authors: Siwicki Andrzej K. , Terech-Majewska Elzbieta , Grudniewska Joanna , Malaczewska Joanna , Kazun Krzysztof , Lepa Agnieszka 
Published: March 2010

Abstract
The influence of deltamethrin on the innate immunity in rainbow trout was examined. Fish were immersed in deltamethrin at doses of 1, 2, and 4 µg/L for 30 min. The results showed that deltamethrin at doses of 2 and 4 µg/L decreased phagocytic activity of spleen macrophages and proliferative response of pronephros lymphocytes at days 1, 2, and 5 after immersion. Deltamethrin at these doses decreased the lysozyme activity, total protein, and immunoglobulin levels in serum. The greatest immunosuppressive influence of deltamethrin at dose 4 µg/L was observed at the end of the study. Environ. Toxicol. Chem. 2010;29:489–491. © 2009 SETAC
Impact of microcystin containing diets on physiological performance of Nile tilapia (Oreochromis niloticus) concerning stress and growth
Authors: Ziková Andrea , Trubiroha Achim , Wiegand Claudia , Wuertz Sven , Rennert Bernhard , Pflugmacher Stephan , Kopp Radovan , Mareš Jan , Kloas Werner 
Published: March 2010

Abstract
Diets containing Microcystis with considerable amounts of the cyanotoxin microcystin-LR (MC-LR) were fed to determine their impact on the physiological performance of the omnivorous Nile tilapia (Oreochromis niloticus) with regard to stress and growth performance. Four different diets were prepared based on a commercial diet (control, MC-5% [containing 5% dried Microcystis biomass], MC-20% [containing 20% dried Microcystis biomass], and Arthrospira-20% [containing 20% dried Arthrospira sp. biomass without toxin]) and fed to female Nile tilapia. Blood and tissue samples were taken after 1, 7, and 28 d, and MC-LR was quantified in gills, muscle, and liver by using high-performance liquid chromatography (HPLC). Only in the liver were moderate concentrations of MC-LR detected. The stress hormone cortisol and glucose were analyzed from plasma, suggesting that all modified diets caused only minor to moderate stress, which was confirmed by analyses of hepatic glycogen. In addition, the effects of the different diets on growth performance were investigated by determining gene expression of hypophyseal growth hormone (GH) and hepatic insulin-like growth factor-I (IGF-I). For all diets, quantitative reverse transcription-polymerase chain reaction (RT-qPCR) demonstrated no significant effect on gene expression of the major endocrine hormones of the growth axis, whereas classical growth data, including growth and feed conversion ratio, displayed slight inhibitory effects of all modified diets independent of their MC-LR content. However, no significant change was found in condition or hepatosomatic index among the various diets, so it seems feasible that dried cyanobacterial biomass might be even used as a component in fish diet for Nile tilapia, which requires further research in more detail. Environ. Toxicol. Chem. 2010;29:561–568. © 2009 SETAC
Effect of nitrite on early-life stages of common carp (Cyprinus carpio L.)
Authors: Kroupova Hana , Prokes Miroslav , Macova Stanislava , Penaz Milan , Barus Vlastimil , Novotny Ladislav , Machova Jana 
Published: March 2010

Abstract
A one-month chronic exposure of common carp larvae and embryos to nitrite revealed significant (p &lt; 0.01) differences in total accumulated mortality in fish exposed to 33, 67, and 330 mg/L NO 2− compared with controls. At the highest concentration, all fish died within 8 d of exposure. On the basis of accumulated mortality in the experimental groups, lethal concentrations of nitrite were estimated at 29 d LC50 = 88 mg/L NO 2−; lowest-observed-effect concentration (LOEC) = 28 mg/L NO 2−; and no-observed-effect concentration (NOEC) = 7 mg/L NO 2−. Fulton's condition factor values were significantly lower in fish from all experimental groups compared with controls. By day 12, fish exposed to 33 and 67 mg/L NO 2− had significantly lower mass and total length compared with controls. No significant negative effects of nitrite at the concentrations tested (0.7–330 mg/L NO 2−, at 10 mg/L Cl−) on hatching or embryo viability were demonstrated, but significant differences in early ontogeny among groups were noted. Fish from all the concentrations showed a dose-related delay in development compared with the controls. Lordosis, kyphosis, scoliosis, and body shortening were observed at all concentrations and in controls, as was yolk sac deformation and edema, eye deformation, and cardiac edema. The incidence of these malformations was positively correlated with nitrite concentration. Histopathology revealed epidermal spongiosis; edema and hyperplasia of the gill epithelium, including hypertrophy and hyperplasia of eosinophilic granular cells (chloride cells); and interstitial edema of skeletal muscle in fish exposed to 67 mg/L NO 2−. Similar, but milder, changes were observed at lower nitrite concentrations. Environ. Toxicol. Chem. 2010;29:535–540. © 2009 SETAC
Bacterial community dynamics in high and low bioavailability soils following laboratory exposure to a range of hexahydro-1,3,5-trinitro-1,3,5-triazine concentrations
Authors: Anderson Jennifer A.H. , Cañas Jaclyn E. , Long Monique K. , Zak John C. , Cox Stephen B. 
Published: March 2010

AbstractFew studies have examined the potential long-term effects of high concentrations of hexahydro-1,3,5-trinitro-1,3,5-triaxine (RDX) on bacterial communities in soil. In the present study, a sandy loam soil and a silt loam soil (high and low bioavailability, respectively) were artificially contaminated with RDX (0, 50, 500, 1,500, 5,000, 10,000, and 15,000 mg/kg soil). Bacterial communities from each treatment were monitored over 63 d to characterize the effects of RDX exposure on bacterial activity, biomass, functional diversity (Biolog microtiter plates), and structural diversity (denaturing gradient gel electrophoresis of 16S rDNA). Bacterial communities native to the high bioavailability soil were inherently different than bacterial communities native to the silt loam soil, not only in terms of bacterial activity and biomass, but also in terms of bacterial community functional and structural diversity. Soil RDX contamination was correlated with decreased bacterial biomass in the silt loam soil treatments and with decreased bacterial activity in the sandy loam soil treatments on day 7. Soil RDX contamination did not cause a significant shift in the functional diversity of the bacterial communities native to the silt loam soil, but was correlated with a shift in identities of substrates used by bacterial communities native to the sandy loam soil on day 7. Bacterial community structure was insensitive to the gradient of RDX concentrations at the beginning of the incubation. However, the identities of carbon substrates used by bacterial communities in both soil types were affected by long-term incubation with RDX. Environ. Toxicol. Chem. 2010;29:38–44. © 2009 SETAC
Polychlorinated biphenyl elimination rates and changes in chemical activity in hibernating amphibians
Authors: Angell Robin A. , Haffner G. Douglas 
Published: March 2010

Abstract
The present study examined polychlorinated biphenyl (PCB) elimination rates in overwintering green frogs (Rana clamitans) to determine if changes in chemical activity occurred during hibernation. Adult green frogs were dosed with a 1:1:1 ratio of Aroclors 1248:1254:1260 in sunflower oil and allowed to enter into hibernation. Frogs were collected at four time points over the course of 85 days. Significant PCB elimination rates ranged from 0.0027 to 0.0376 d−1. A negative correlation was found between KOW and elimination rate. Over the course of the present study, a decrease in total body percent lipid was measured. There was an overall increase in fugacity of higher KOW compounds corresponding to the relatively rapid decrease in lipid content. Congeners in metabolic group 2 (meta-para vicinal hydrogen atoms) were preferentially eliminated over those in metabolic group 3 (ortho-meta vicinal hydrogen atoms), suggesting that biotransformation was occurring during hibernation. It was concluded that metabolic activity during hibernation, associated with water temperature, was sufficiently high to reduce lipid concentrations and increase chemical activity in emerging adults. Environ. Toxicol. Chem. 2010;29:700–707. © 2009 SETAC
Mercury concentrations in landlocked Arctic char (Salvelinus alpinus) from the Canadian Arctic. Part I: Insights from trophic relationships in 18 lakes
Authors: Gantner Nikolaus , Power Michael , Iqaluk Deborah , Meili Markus , Borg Hans , Sundbom Marcus , Solomon Keith R. , Lawson Greg , Muir Derek C. 
Published: March 2010

Abstract
Concentrations of mercury (Hg) have increased slowly in landlocked Arctic char over a 10- to 15-year period in the Arctic. Fluxes of Hg to sediments also show increases in most Arctic lakes. Correlation of Hg with trophic level (TL) was used to investigate and compare biomagnification of Hg in food webs from lakes in the Canadian Arctic sampled from 2002 to 2007. Concentrations of Hg (total Hg and methylmercury [MeHg]) in food webs were compared across longitudinal and latitudinal gradients in relation to δ13C and δ15N in periphyton, zooplankton, benthic invertebrates, and Arctic char of varying size-classes. Trophic magnification factors (TMFs) were calculated for the food web in each lake and related to available physical and chemical characteristics of the lakes. The relative content of MeHg increased with trophic level from 4.3 to 12.2% in periphyton, 41 to 79% in zooplankton, 59 to 72% in insects, and 74 to 100% in juvenile and adult char. The δ13C signatures of adult char indicated coupling with benthic invertebrates. Cannibalism among char lengthened the food chain. Biomagnification was confirmed in all 18 lakes, with TMFs ranging from 3.5 ± 1.1 to 64.3 ± 0.8. Results indicate that TMFs and food chain length (FCL) are key factors in explaining interlake variability in biomagnification of [Hg] among different lakes. Environ. Toxicol. Chem. 2010;29:621–632. © 2009 SETAC
Cytotoxicity, calcium release, and pH changes generated by novel calcium phosphate cement formulations
Authors: Khashaba Rania M. , Lockwood Petra E. , Lewis Jill B. , Messer Regina L. , Chutkan Norman B. , Borke James L. 
Published: March 2010

AbstractFew published studies describe the biological properties of calcium phosphate cements (CPCs) for dental applications. We measured several biologically relevant properties of 3 CPCs over an extended (8 wk) interval. Monocalcium phosphate, calcium oxide, and synthetic hydroxyapatite were combined with either modified polyacrylic acid, light‐activated modified polyalkenoic acid, or 35% w/w polymethyl vinyl ether maleic acid to obtain Types I, II, and III CPCs, respectively. Set cements were placed in direct contact with L929 fibroblasts for up to 8 weeks. Media Ca+2 and pH were determined by atomic absorption spectroscopy and pH electrode respectively. Cell mitochondrial function was measured by MTT assay. Type I cements suppressed mitochondrial activity > 90% (vs. Teflon controls), but significantly (p < 0.05) improved to control levels over 8 weeks. Type II cements suppressed mitochondrial activity > 90% at all times. Type III cements elevated mitochondrial activity significantly after 7 wks. The pH profiles approached neutrality by 24 h, and all cements released calcium into the storage medium at all periods (24 h ‐ 8 wk). We concluded that several types of cements had long‐term biological profiles that show promise for dental applications. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010
The paradox of readmission: Effect of a quality improvement program in hospitalized patients with heart failure
Authors: Mudge Alison , Denaro Charles , Scott Ian , Bennett Cameron , Hickey Annabel , A. Jones Mark 
Published: March 2010

AbstractBACKGROUND:Congestive heart failure (CHF) is an increasingly common condition associated with significant hospital resource utilization. Initiating better disease management at the time of initial hospital admission has the potential to reduce readmissions.OBJECTIVE:To evaluate the impact of a multifaceted quality improvement program on 12‐month hospital utilization in patients admitted to hospital with CHF.DESIGN:Prospective longitudinal study comparing baseline and intervention cohorts.PARTICIPANTS:All consecutive patients with CHF discharged alive from 3 metropolitan hospitals during the baseline (October 1, 2000 to April 17, 2001) and intervention (February 15, 2002 to August 31, 2002) study periods. Active prospective case‐finding identified 220 baseline and 235 intervention participants; full data was available on 197 baseline and 219 intervention participants.INTERVENTIONS:Education and performance feedback for hospital and primary care practitioners; clinical decision support tools; individualized, guideline‐based treatment plans; patient education and self‐management support; and improved hospital–community integration.MEASUREMENTS:Twelve‐month all‐cause hospital readmission, 12‐month mortality, readmission‐free survival, heart failure–specific readmission, and total hospital days over 12 months.RESULTS:Intervention patients had a higher rate of all‐cause readmission (odds ratio [OR] = 1.65; 95% confidence interval [CI] = 1.10‐2.46) but a trend to reduction in mortality (OR = 0.68; 95% CI = 0.44‐1.07). There was no difference in frequency of hospitalizations per year, number of hospital days, or the composite outcome of death or readmission.CONCLUSIONS:The intervention improved care processes and may have reduced mortality, but at the cost of higher readmission rates. Better understanding of intervention components, intensity, and targeting may optimize the effectiveness of disease management programs. Journal of Hospital Medicine 2010;5:148–153. © 2010 Society of Hospital Medicine.
The record from British Quaternary river systems within the context of global fluvial archives
Authors: Bridgland David R. 
Published: March 2010

AbstractData amassed in the past decade on Quaternary fluvial archives has allowed comparison across widely separated regions of the world. Meanwhile there has been a new impetus for research on British sequences, as a result particularly of the Aggregates Levy Sustainability Fund (ALSF). In this context, the key British records (from the Thames, Severn–Avon, Trent, Wash system and Solent) are described briefly, with emphasis on the latest information. In the case of the Trent, sedimentary evidence, discovered during ALSF‐funded work, appears to confirm the existence of a Middle Pleistocene ‘Trent–Ancaster’ River. In the case of the Solent, independent projects that sought to improve the age constraint for the sequence have produced complimentary results; the first used luminescence dating, whereas the second made use of Palaeolithic evidence to calibrate numerical incision/uplift modelling. The overarching message is that the British fluvial archive can be readily understood within a global context; it typifies records from areas with relatively young crust that has been uplifting during the Quaternary and, being in the temperate latitudes and close to the Atlantic margin, it reflects strong climatic forcing. The combination of rich faunal and Palaeolithic artefact contents means that certain British records are of international significance. Copyright © 2010 John Wiley & Sons, Ltd.
Reconstructing Holocene palaeoclimate and palaeoceanography in Ìsafjarðardjúp, northwest Iceland, from two fjord records overprinted by relative sea‐level and local hydrographic changes
Authors: Quillmann Ursula , Jennings Anne , Andrews John 
Published: March 2010

AbstractWe reconstruct palaeoclimate and palaeoceanography of the Ísafjarðardjúp fjord system from two cores – one from the inner fjord and one near the fjord mouth – while separating the potential overprinting of relative sea‐level (RSL) and local fjord hydrographic changes on these records. The inner fjord core (B997‐339) reflects local fjord hydrography; the outer fjord core (MD99‐2266) reflects the regional oceanic signal. Glacial marine conditions ended at ca. 10 200 cal. a BP, indicated by both ice‐rafted debris records. The other proxy records show spatial and temporal variability within the fjord system. At the inner fjord site (B997‐339) foraminiferal assemblages and the δ18O record indicate lowered RSL between ca. 10 600 and 8900 cal. a BP and document the onset of fjord water overturning at ca. 8900 cal. a BP, which obscured the climate record. At the fjord mouth (MD99‐2266) mass accumulation rates suggest lowered RSL between ca. 10 200 and 5500 cal. a BP and local freshwater and/or reduced salinities of the Irminger Current water masses affected the δ18O signal between ca. 10 200 and 7900 cal. a BP. At MD99‐2266, foraminiferal fauna record the Holocene Thermal Maximum between ca. 8000 and 5700 cal. a BP and the onset of modern oceanic circulation at ca. 7000 cal. a BP. Copyright © 2010 John Wiley & Sons, Ltd.
Raman spectroscopic study of the hydrogen and arsenate bonding environment in isostructural synthetic arsenates of the variscite group—M3+ AsO4·2H2O (M3+ = Fe, Al, In and Ga): implications for arsenic release in water
Authors: Gomez Mario A. , Le Berre Jean‐Francois , Assaaoudi Hassane , Demopoulos George P. 
Published: March 2010

AbstractThe Raman spectra of synthetic compounds equivalent to the variscite group: FeAsO4·2H2O AlAsO4·2H2O, GaAsO4·2H2O, and InAsO4·2H2O are reported. In particular, upon comparison of FeAsO4·2H2O to AlAsO4·2H2O, it is observed that the Type II (weak) H‐bond lengths in the latter are slightly longer, which is postulated to affect the stability (As release) in water at pH 5 and 7. Arsenate stretching and bending vibrations were found to be distinct in terms of spectral structure and therefore well suited for fingerprinting. The calculated AsO bond strengths from existing crystallographic data showed no significant variations. The strongest ν1 (AsO43−) stretch was used to monitor the AsO bonding interactions in the four AsOM units, where a shift of 114 cm−1 was observed in the order FeAsO4·2H2O (lowest) < InAsO4·2H2O < GaAsO4·2H2O < AlAsO4·2H2O (highest); this order also followed exactly the measured arsenic release of these phases. This shift in ν1 (AsO43−) position was rationalized to stem from the differences in the electronegativities of the M3+ cations. The trends mentioned above were verified and found to also hold for the isostructural phosphate analogues strengite (FePO4·2H2O) and variscite (AlPO4·2H2O) using published data. Therefore, it is postulated that, as observed with the stability of solution complexes, there may be a correlation between the electronegativity of the M3+ cation in these isostructural phases and their stability (As or P release) in water. Copyright © 2010 John Wiley & Sons, Ltd.
Preparative isolation and purification of anti‐tumor agent ansamitocin P‐3 from fermentation broth of Actinosynnema pretiosum using high‐performance counter‐current chromatography
Authors: Yao Yuqin , Cheng Zhihui , Ye Haoyu , Xie Yongmei , He Jing , Tang Minghai , Shen Tao , Wang Jiangman , Zhou Yan , Lu Zejun , Luo Feng , Chen Lijuan , Yu Luoting , Yang Jin‐Liang , Peng Aihua , Wei Yuquan 
Published: March 2010

AbstractAnsamitocin P‐3 is a potent anti‐tumor maytansinoid found in Actinosynnema pretiosum. However, due to the complexity of the fermentation broth of Actinomycete, how to effectively separate ansamitocin P‐3 is still a challenge. In this study, both analytical and preparative high‐performance counter‐current chromatography were successfully used to separate and purify ansamitocin P‐3 from fermentation broth. A total of 28.8 mg ansamitocin P‐3 with purity of 98.4% was separated from 160 mg crude sample of fermentation broth in less than 80 min with the two‐phase solvent system of hexane–ethyl acetate–methanol–water (0.6:1:0.6:1, v/v/v/v). The purity and structural identification were determined by HPLC, 1H NMR, 13C NMR and mass spectroscopy.