bluuebunny/crossref_metadata_2025_split huggingface dataset:
Racemic and Optically Pure Heptahelicene‐2‐carboxylic Acid: Its Synthesis and Self‐Assembly into Nanowire‐Like Aggregates (Eur. J. Org. Chem. 5/2011)
Authors: Rybáček Jiří , Huerta‐Angeles Gloria , Kollárovič Adrian , Stará Irena G. , Starý Ivo , Rahe Philipp , Nimmrich Markus , Kühnle Angelika 
Published: February 2011

AbstractThe cover picture shows heptahelicene‐2‐carboxylic acid, whose synthesis and self‐assembly are central to the article. The background features Prague's riverbank, which is intermixed with the nanowire‐like aggregates of heptahelicene‐2‐carboxylic acid. The alignment of the swans makes the link between self‐assembly and the Prague view. Details are discussed in the article by I. G. Stará, I. Starý, A. Kühnle et al. on p. 853 ff. Background photo by M. Bělohradský.
Effects of AC‐Electrolysis on the Enzymatic Activity of Glucose Oxidase
Authors: Ammam Malika , Fransaer Jan 
Published: February 2011

AbstractThe change in the activity of glucose oxidase subjected to an asymmetrical alternating current (AC) electric field is investigated via horseradish peroxidase (HRP)‐coupled bioassay. The effect of the amplitude, frequency and enzyme concentration have been shown to affect the enzyme activity towards glucose oxidation. The decrease in the enzyme activity is directly related to the change in pH and temperature of the GOx solution during AC electrolysis. The enzyme activity reduces with increasing amplitude, enzyme concentration and decreasing frequency. Results from UV‐vis, FT‐IR and UV CD spectroscopy showed that the AC treated GOx samples undergo structural modifications.
Effects of aging and mixed nonaqueous-phase liquid sources in soil systems on earthworm bioaccumulation, microbial degradation, sequestration, and aqueous desorption of pyrene
Authors: Petersen Elijah J , Tang Jixin , Weber Walter J 
Published: February 2011

Abstract
The effects of loading and aging pyrene in soils in the presence of four environmentally common nonaqueous-phase liquids (NAPLs) (hexadecane, 2,2,4,4,6,8,8-heptamethylnonane [HMN], toluene, and dimethyl phthalate [DMP]) on its subsequent desorption from those soils, earthworm accumulation, biodegradation, and extractability were tested by using two dissimilar soils. The presence of each of the four NAPLs increased fractions and rates of pyrene desorption, and hexadecane slowed the effects of aging on these same parameters. Loading with hexadecane and HMN caused earthworm accumulation of pyrene to decrease. These results contrast with generally observed faster desorption rates resulting from NAPL addition, suggesting that additional factors (e.g., association of pyrene with NAPL phases and NAPL toxicities to earthworms) may impact bioaccumulation. The presence of HMN and toluene increased pyrene biodegradation, whereas hexadecane and DMP had the opposite effects. These results correlate with changes in the extractability of pyrene from the soils. After aging and biodegradation, hexadecane and DMP substantially increased pyrene residues extractable by methanol and decreased nonextractable fractions, whereas HMN and toluene had the opposite effects. Environ. Toxicol. Chem. 2011; 30:988–996. © 2010 SETAC
Use of vegetated agricultural drainage ditches to decrease pesticide transport from tomato and alfalfa fields in California, USA
Authors: Moore Matthew T , Denton Debra L , Cooper Charles M , Wrysinski Jeanette , Miller Jeff L , Werner Inge , Horner Gerald , Crane David , Holcomb Diane B , Huddleston George M 
Published: February 2011

Abstract
Irrigation and storm water runoff from agricultural fields has the potential to cause impairment to downstream aquatic receiving systems. Over the last several years, scientists have discovered the benefit of using edge-of-field practices, such as vegetated agricultural drainage ditches, in the mitigation of pesticides and sediment. After demonstrating this practice's feasibility in California, field trials were initiated to document irrigation runoff pesticide mitigation in California alfalfa and tomato fields. In the alfalfa field, chlorpyrifos concentration was decreased by 20% from the inflow to the ditch outflow. Thirty-two percent of the measured chlorpyrifos mass was associated with ditch plant material. In the tomato field, permethrin concentration was decreased by 67% and there was a 35% reduction in suspended sediment concentration from inflow to the ditch outflow. When surface water was not present in the ditch systems, the sediment was a significant repository for pesticides. Based on the field trials, vegetated agricultural drainage ditches can be successfully used as part of a suite of management practices to reduce pesticide and sediment runoff into aquatic receiving systems. Environ. Toxicol. Chem. 2011; 30:1044–1049. © 2011 SETAC
Simulation of the spatio‐temporal extent of groundwater flooding using statistical methods of hydrograph classification and lumped parameter models
Authors: Upton K. A. , Jackson C. R. 
Published: February 2011

AbstractThis article presents the development of a relatively low cost and rapidly applicable methodology to simulate the spatio‐temporal occurrence of groundwater flooding in chalk catchments. In winter 2000/2001 extreme rainfall resulted in anomalously high groundwater levels and groundwater flooding in many chalk catchments of northern Europe and the southern United Kingdom. Groundwater flooding was extensive and prolonged, occurring in areas where it had not been recently observed and, in places, lasting for 6 months. In many of these catchments, the prediction of groundwater flooding is hindered by the lack of an appropriate tool, such as a distributed groundwater model, or the inability of models to simulate extremes adequately. A set of groundwater hydrographs is simulated using a simple lumped parameter groundwater model. The number of models required is minimized through the classification and grouping of groundwater level time‐series using principal component analysis and cluster analysis. One representative hydrograph is modelled then transposed to other observed hydrographs in the same group by the process of quantile mapping. Time‐variant groundwater level surfaces, generated using the discrete set of modelled hydrographs and river elevation data, are overlain on a digital terrain model to predict the spatial extent of groundwater flooding. The methodology is applied to the Pang and Lambourn catchments in southern England for which monthly groundwater level time‐series exist for 52 observation boreholes covering the period 1975–2004. The results are validated against observed groundwater flood extent data obtained from aerial surveys and field mapping. The method is shown to simulate the spatial and temporal occurrence of flooding during the 2000/2001 flood event accurately. British Geological Survey © NERC 2011. Hydrological Processes © 2011 John Wiley & Sons, Ltd.
Lysimeter soil water balance evaluation for an experiment developed in the Southern Brazilian Atlantic Forest region
Authors: Feltrin Rafael Matias , de Paiva João Batista Dias , de Paiva Eloiza Maria Cauduro Dias , Beling Fábio Alex 
Published: February 2011

AbstractThis study aims at monitoring the behaviour of the rainfall, runoff, drainage, soil water storage, and evapotranspiration variables involved in the water balance measured by lysimeter data. The evaluation of the water balance considered different time scales, where the components were monitored daily and in 10‐day accumulated period intervals. The results demonstrated that in wet periods the soil water content was greater at a depth of 10 cm, whereas in the dry periods a greater concentration was observed at 70 cm depth. At the depth of 30 cm, the lowest values of soil water content were observed for both wet and dry periods. The results, obtained through the use of tensiometers and time domain reflectometry installed internally and externally to the lysimeter, were very close, which was more noticeable during the periods of lower water loss by the soil. The water balance, calculated from the lysimeter data, demonstrated that 70% of the total rainfall was lost by the process of evapotranspiration. The drainage accounted for 27·5% of the precipitated water, highlighting the fact that this component should not be disregarded in the water balance calculation. Copyright © 2011 John Wiley & Sons, Ltd.
Load or concentration, logged or unlogged? Addressing ten years of uncertainty in neural network suspended sediment prediction
Authors: Mount Nick J. , Abrahart Robert J. 
Published: February 2011

AbstractThis paper addresses current inconsistencies in methodological approaches for neural network modelling of suspended sediment. An expansion in the number of case studies being published over the last decade has yet to result in agreed guidelines on whether suspended sediment load or concentration should be modelled, and whether log‐transformation of data is either necessary or potentially beneficial. This contrasts with the well‐recognized guidelines that direct traditional sediment rating curve studies. The paper reports a comprehensive set of single‐input single‐output neural network suspended sediment modelling experiments performed on two catchments in Puerto Rico. It examines the impact of internal complexity, input variable choice and data transformation on the form, consistency and physical rationality of model outputs, the existence of localized overfitting and the usefulness of global performance metrics. Sound guidance on whether to model sediment load or concentration, and whether to model log‐transformed data is provided. Copyright © 2011 John Wiley & Sons, Ltd.
Water storage dynamics and runoff response of a boreal Shield headwater catchment
Authors: Oswald Claire J. , Richardson Murray C. , Branfireun Brian A. 
Published: February 2011

AbstractThresholds in terrestrial water storage were quantified to explain differences in observed rainfall‐runoff relationships for a 71·5 ha research catchment in northwestern Ontario, Canada. Using terrain analysis techniques, the catchment was partitioned into discrete hydrologic response units (HRUs). Unsaturated and saturated water storage was calculated for depression and midslope HRUs using continuous hydrometric measurements and a depth function for drainable porosity. The relationship between total water storage in these HRUs and catchment discharge was then examined for evidence of threshold behaviour. Piecewise regression analysis (PRA) was used to quantify a breakpoint in the nonlinear storage‐discharge relationship, with separate linear regressions explaining the change in discharge with storage above and below this value. Above the breakpoint, a large increase in discharge is associated with a small increase in storage. Our results show that event‐scale hydrologic response displays a threshold relationship with antecedent storage and maximum event storage in the terminal depression in the catchment. Our results also suggest that predictions of event runoff improve when storage excesses from upslope depressions are explicitly routed through the catchment taking into consideration storage deficits in downslope HRUs that may impede flow. The application of landscape delineation, hydrometric monitoring and PRA to model S‐Q relationships is demonstrated to be an objective means of quantifying the transition between the two distinct hydrologic regimes in this catchment and provides new insight into how S‐Q dynamics govern the hydrologic functioning of bedrock‐dominated catchments. Copyright © 2011 John Wiley & Sons, Ltd.
The orally bioavailable met inhibitor PF-2341066 inhibits osteosarcoma growth and osteolysis/matrix production in a xenograft model
Authors: Sampson Erik R , Martin Brad A , Morris Aimee E , Xie Chao , Schwarz Edward M , O'Keefe Regis J , Rosier Randy N 
Published: February 2011

Abstract
Osteosarcoma (OS) is the most common primary bone tumor in children and adolescents. Ninety percent of patients who present with metastatic and 30% to 40% of patients with nonmetastatic disease experience relapse, creating an urgent need for novel therapeutic strategies. The Met receptor tyrosine kinase and its ligand, hepatocyte growth factor (HGF), are important for mitosis, motility, and cell survival. Upregulation of Met/HGF signaling via receptor overexpression, amplification, or mutation drives the proliferation, invasiveness, and metastasis of a variety of cancer cells, including OS, prompting the development of Met/HGF inhibitors. OS cells depend on Met overexpression because introduction of dominant-negative Met inhibits in vivo tumorigenicity. Despite the importance of Met/HGF signaling in the development and maintenance of OS, the potential efficacy of pharmacologic Met inhibition in OS has been addressed only in in vitro studies. PF-2341066 is an orally bioavailable, selective ATP-competitive Met inhibitor that showed promising results recently in a phase I clinical trial in non–small cell lung cancer (NSCLC) patients. We tested the ability of PF-2341066 to inhibit malignant properties of osteosarcoma cells in vitro and orthotopic xenograft growth in vivo. In vitro, PF-2341066 inhibited osteosarcoma behavior associated with primary tumor growth (eg, proliferation and survival) as well as metastasis (eg, invasion and clonogenicity). In nude mice treated with PF-2341066 via oral gavage, the growth and associated osteolysis and extracortical bone matrix formation of osteosarcoma xenografts were inhibited by PF-2341066. PF-2341066 may represent an effective new systemic therapy for localized and potentially disseminated osteosarcoma. © 2011 American Society for Bone and Mineral Research.
Retinol (vitamin A) maintains self‐renewal of pluripotent male germline stem cells (mGSCs) from adult mouse testis
Authors: Zhang Shanshan , Sun Junwei , Pan Shaohui , Zhu Haijing , Wang Long , Hu Yue , Wang Jing , Wang Fang , Cao Hui , Yan Xinrong , Hua Jinlian 
Published: February 2011

AbstractStudies have shown that male germline stem cells (mGSCs), which are responsible for maintaining spermatogenesis in the male, could be obtained from mouse and human testis. However, the traditional cultural methods were mostly dependent on serum and feeder, and the initial mGSCs were either obtained from neonatal mice or the detailed description of its potency and origin was not provided. Here we reported a novel (retinol (RE) serum‐free and feeder‐free) system for the successful culture of adult germline stem cells from adult Kunming mice (8–24 weeks) testis. The isolated mGSCs cultured in RE serum‐free and feeder‐free medium maintained the typical morphology of undifferentiated embryonic stem cells (ESCs), and they proliferated well in RE medium analyzed by proliferation assay, RT‐PCR, microarray, and Western blotting. These cells also showed typical properties of ESCs (alkaline phosphatase (AP) positive, expressions of Oct4, Sox2, Nanog, and SSEA1, with the capacity to form teratomas and differentiate into various types of cells within three germ layers). Taken together, we conclude that RE promotes the self‐renewal of mGSCs and maintains the pluripotency of mGSCs, the RE serum‐free and feeder‐free system may be useful for the culture of pluripotent stem cell lines from adult testis tissues, which provides a new resource for tissue engineering and therapy for infertility. J. Cell. Biochem. 112: 1009–1021, 2011. © 2011 Wiley‐Liss, Inc.
Protein phosphatase 1‐dependent dephosphorylation of Akt is the prime signaling event in sphingosine‐induced apoptosis in Jurkat cells
Authors: Thayyullathil Faisal , Chathoth Shahanas , Shahin Allen , Kizhakkayil Jaleel , Hago Abdulkader , Patel Mahendra , Galadari Sehamuddin 
Published: February 2011

AbstractSphingosine (SPH) is an important bioactive lipid involved in mediating a variety of cell functions including apoptosis. However, the signaling mechanism of SPH‐induced apoptosis remains unclear. We have investigated whether SPH inhibits survival signaling in cells by inhibiting Akt kinase activity. This study demonstrates that treatment of Jurkat cells with SPH leads to Akt dephosphorylation as early as 15 min, and the cells undergo apoptosis after 6 h. This Akt dephosphorylation is not mediated through deactivation of upstream kinases, since SPH does not inhibit the upstream phosphoinositide‐dependent kinase 1 (PDK1) phosphorylation. Rather, sensitivity to the Ser/Thr protein phosphatase inhibitors (calyculin A, phosphatidic acid, tautomycin, and okadaic acid) indicates an important role for protein phosphatase 1 (PP1) in this process. In vitro phosphatase assay, using Akt immunoprecipitate following treatment with SPH, reveals an increase in Akt‐PP1 association as determined by immunoprecipitation analysis. Moreover, SPH‐induced dephosphorylation of Akt at Ser473 subsequently leads to the activation of GSK‐3β, caspase 3, PARP cleavage, and ultimately apoptosis. Pre‐treatment with caspase 3 inhibitor z‐VAD‐fmk and Ser/Thr phosphatase inhibitor abrogates the effect of SPH on facilitating apoptosis. Altogether, these results demonstrate that PP1‐mediated inhibition of the key anti‐apoptotic protein, Akt, plays an important role in SPH‐mediated apoptosis in Jurkat cells. J. Cell. Biochem. 112: 1138–1153, 2011. © 2011 Wiley‐Liss, Inc.
Model potentials for molecular calculations. I. The sd‐MP set for transition metal atoms Sc through Hg
Authors: Sakai Yoshiko , Miyoshi Eisaku , Klobukowski Mariusz , Huzinaga Sigeru 
Published: February 2011

AbstractModel potential parameters and valence orbitals were generated for the transition metal atoms Sc through Hg. Only the nd and (n + 1)s valence electrons were treated explicitly and the effects of the remaining electrons were replaced by model potentials. For brevity they may be called sd‐MPs. Major relativistic effects were incorporated on the level of Cowan and Griffin's quasirelativistic Hartree‐Fock (QRHF) method for the second and third transition metal atoms. The model potential parameters and valence orbitals were determined so as to reproduce the results of the numerical Hartree‐Fock reference calculations. The obtained valence orbitals have inner nodal structure. The model potential method can yield a balanced description of the s2dn–1, sdn, and dn + 1 configurations of the atoms. The polarization functions were also generated for the use in molecular calculations.
Regulation of apoptosis and autophagy by sphingosylphosphorylcholine in vascular endothelial cells
Authors: Ge Di , Jing Qingchuan , Meng Ning , Su Le , Zhang Yun , Zhang Shangli , Miao Junying , Zhao Jing 
Published: February 2011

AbstractSphingosylphosphorylcholine (SPC), an important cardiovascular mediator derived from sphingomyelin that has atheroprotective effects via actions on vascular endothelial cells (VECs) at normal levels in vivo. However, the underlying mechanism is not well known. To clarify this question, we first investigated the effect of SPC on VEC apoptosis and autophagy induced by deprivation of serum and fibroblast growth factor 2 (FGF‐2). SPC at 5–20 µM inhibited apoptosis and induced autophagy in vitro. To understand the underlying mechanism, we investigated the role of integrin β4 in SPC‐induced autophagy in VECs. SPC significantly decreased the level of integrin β4, whereas overexpression of integrin β4 inhibited SPC‐induced autophagy. Moreover, knockdown of integrin β4 promoted VEC autophagy. To understand the downstream factors of integrin β4 in this process, we observed the effects of SPC on phosphatidylcholine‐specific phospholipase C (PC‐PLC) activity and level of p53. PC‐PLC activity and p53 level in cytoplasm was decreased during autophagy induced by SPC, and knockdown of integrin β4 inhibited the activity of PC‐PLC and the cytoplasmic level of p53. SPC may promote autophagy via integrin β4. Moreover, PC‐PLC and p53 may be the downstream factors of integrin β4 in autophagy of VECs deprived of serum and FGF‐2. J. Cell. Physiol. 226: 2827–2833, 2011. © 2011 Wiley‐Liss, Inc.
Bcr‐Abl oncogene stimulates jab1 expression via cooperative interaction of β‐catenin and STAT1 in chronic myeloid leukemia cells
Authors: Yang Kuei‐Ting , Wang Ming‐Chung , Chen Jing‐Yi , Hsu Ming‐Chuan , Hung Wen‐Chun 
Published: February 2011

AbstractJab1, a co‐activator of AP‐1 transcription factor and the fifth subunit of the COP9 signalosome, mediates degradation of the tumor suppressor p53 and p27Kip1 and functions as a tumor promoter in different types of human cancer. In this study, we show that inhibition of Bcr‐Abl oncogene by imatinib induces down‐regulation of Jab1 in Bcr‐Abl‐positive K562, Ku812, and MEG01 leukemia cells suggesting Bcr‐Abl may regulate Jab1 expression. Promoter deletion and mutation analysis indicate the Tcf‐4/β‐catenin and STAT1 binding sites located between the −405/−223 region of the human Jab1 promoter are important for the activation of Jab1 by Bcr‐Abl. Double mutation of these two sites reverses the inhibitory effect of imatinib. Chromatin immunoprecipitation assay verifies the binding of β‐catenin and STAT1 to human Jab1 promoter. Ectopic expression of dominant‐negative Tcf‐4 mutant significantly attenuates Jab1 expression while over‐expression of β‐catenin and STAT1 cooperatively up‐regulates Jab1 promoter activity and mRNA expression. Our results also demonstrate that the AKT signaling pathway is involved in the regulation of Jab1 by Bcr‐Abl because the AKT inhibitor LY294002 but not the ERK inhibitor PD98059 reduces Jab1 promoter activity and mRNA expression. Taken together, our results suggest that Bcr‐Abl stimulates Jab1 expression via the cooperative interaction of β‐catenin and STAT1 in leukemia cells. J. Cell. Physiol. 226: 2849–2856, 2011. © 2011 Wiley‐Liss, Inc.
Unexpectedly low mutation rates in beta‐myosin heavy chain and cardiac myosin binding protein genes in italian patients with hypertrophic cardiomyopathy
Authors: Roncarati Roberta , Latronico Michael V.G. , Musumeci Beatrice , Aurino Stefania , Torella Annalaura , Bang Marie‐Louise , Jotti Gloria Saccani , Puca Annibale A. , Volpe Massimo , Nigro Vincenzo , Autore Camillo , Condorelli Gianluigi 
Published: February 2011

AbstractHypertrophic cardiomyopathy (HCM) is the most common genetic cardiac disease. Fourteen sarcomeric and sarcomere‐related genes have been implicated in HCM etiology, those encoding β‐myosin heavy chain (MYH7) and cardiac myosin binding protein C (MYBPC3) reported as the most frequently mutated: in fact, these account for around 50% of all cases related to sarcomeric gene mutations, which are collectively responsible for approximately 70% of all HCM cases. Here, we used denaturing high‐performance liquid chromatography followed by bidirectional sequencing to screen the coding regions of MYH7 and MYBPC3 in a cohort (n = 125) of Italian patients presenting with HCM. We found 6 MHY7 mutations in 9/125 patients and 18 MYBPC3 mutations in 19/125 patients. Of the three novel MYH7 mutations found, two were missense, and one was a silent mutation; of the eight novel MYBPC3 mutations, one was a substitution, three were stop codons, and four were missense mutations. Thus, our cohort of Italian HCM patients did not harbor the high frequency of mutations usually found in MYH7 and MYBPC3. This finding, coupled to the clinical diversity of our cohort, emphasizes the complexity of HCM and the need for more inclusive investigative approaches in order to fully understand the pathogenesis of this disease. J. Cell. Physiol. 226: 2894–2900, 2011. © 2011 Wiley‐Liss, Inc.