bluuebunny/crossref_metadata_2025_split huggingface dataset:
Active site mutant dimethylarginine dimethylaminohydrolase 1 expression confers an intermediate tumour phenotype in C6 gliomas
Authors: Boult Jessica KR , Walker‐Samuel Simon , Jamin Yann , Leiper James M , Whitley Guy St J , Robinson Simon P 
Published: March 2011

AbstractDimethylarginine dimethylaminohydrolase (DDAH) metabolizes the endogenous inhibitor of nitric oxide synthesis, asymmetric dimethylarginine (ADMA). Constitutive over‐expression of DDAH1, the isoform primarily associated with neuronal nitric oxide synthase (nNOS) results in increased tumour growth and vascularization, and elevated VEGF secretion. To address whether DDAH1‐mediated tumour growth is reliant upon the enzymatic activity of DDAH1, cell lines expressing an active site mutant of DDAH1 incapable of metabolizing ADMA were created. Xenografts derived from these cell lines grew significantly faster than those derived from control cells, yet not as fast as those over‐expressing wild‐type DDAH1. VEGF expression in DDAH1 mutant‐expressing tumours did not differ from control tumours but was significantly lower than that of wild‐type DDAH1‐over‐expressing tumours. Fluorescence microscopy for CD31 and pimonidazole adduct formation demonstrated that DDAH1 mutant‐expressing tumours had a lower endothelial content and demonstrated less hypoxia, respectively, than wild‐type DDAH1‐expressing tumours. However, there was no difference in uptake of the perfusion marker Hoechst 33342. Non‐invasive multiparametric quantitative MRI, including the measurement of native T1 and T2 relaxation times and apparent water diffusion coefficient, was indicative of higher cellularity in DDAH1‐expressing xenografts, which was confirmed by histological quantification of necrosis. C6 xenografts expressing active site mutant DDAH1 displayed an intermediate phenotype between tumours over‐expressing wild‐type DDAH1 and control tumours. These data suggest that enhanced VEGF expression downstream of DDAH1 was dependent upon ADMA metabolism, but that the DDAH1‐mediated increase in tumour growth was only partially dependent upon its enzymatic activity, and therefore must involve an as‐yet unidentified mechanism. DDAH1 is an important mediator of tumour progression, but appears to have addition roles independent of its metabolism of ADMA, which need to be considered in therapeutic strategies targeted against the NO/DDAH pathway in cancer. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Risk of recurrence and survival after relapse in patients with Ewing sarcoma
Authors: Stahl Martin , Ranft Andreas , Paulussen Michael , Bölling Tobias , Vieth Volker , Bielack Stefan , Görtitz Irene , Braun‐Munzinger Gabriele , Hardes Jendrik , Jürgens Heribert , Dirksen Uta 
Published: March 2011

AbstractBackgroundThe prognosis in patients with relapsed Ewing sarcoma is unfavorable. Our investigation identifies factors predicting for the outcome following relapse.ProcedureWe analyzed type of relapse, time to relapse and overall survival after relapse (OSr) in 714 patients with first recurrence. All patients had been treated within the Cooperative Ewing Sarcoma Studies (CESS) 81 or 86, or the European Intergroup CESS (EICESS 92). OSr time was calculated from diagnosis of first relapse to last follow‐up or death.ResultsMedian follow‐up time from diagnosis of primary disease was 2.2 years (mean = 4.0; range: 0.2–24.9). Relapse sites were local in 15%, combined local and systemic in 12%, and systemic in 73%. Among patients with a localized primary tumor, 20% relapsed locally, while 12% showed combined and 68% systemic relapse. When the primary disease was disseminated, 82% developed systemic, 13% combined, and 5% local relapse. Five‐year OSr was 0.13 (SE = 0.01). Outcome following local relapse, with a 5‐year survival rate of 0.24 (P < 0.001), was superior to outcome after systemic or combined recurrence. Five‐year OSr was 0.07 (SE = 0.01) in patients who relapsed 0–2 years after the diagnosis of primary disease, as compared to a 5‐year OSr of 0.29 (SE = 0.03) when relapse occurred later.Conclusions5‐year OSr in Ewing sarcoma is poor (<0.2). Prognostically favorable factors are: late onset (>2 years) and strictly localized relapse. Pediatr Blood Cancer 2011; 57: 549–553. © 2011 Wiley‐Liss, Inc.
Determination of carbohydrates in medicinal plants‐comparison between TLC, mf‐MELDI‐MS and GC‐MS
Authors: Qureshi Muhammad Nasimullah , Stecher Guenther , Sultana Tahira , Abel Gudrun , Popp Michael , Bonn Guenther K. 
Published: March 2011

AbstractIntroduction – Quality control in the pharmaceutical and phytopharmaceutical industries requires fast and reliable methods for the analysis of raw materials and final products.Objective – This study evaluates different analytical approaches in order to recognise the most suitable technique for the analysis of carbohydrates in herbal drug preparations.Methodology – The specific focus of the study is on thin‐layer chromatography (TLC), gas chromatography (GC), and a newly developed mass spectrometric method, i.e. matrix free material enhanced laser desorption/ionisation time of flight mass spectrometry (mf‐MELDI‐MS). Samples employed in the study were standards and microwave‐assisted water extracts from Quercus.Results – TLC analysis proved the presence of mono‐, di‐ and trisaccharides within the biological sample and hinted at the existence of an unknown carbohydrate of higher oligomerisation degree. After evaluation of different derivatisation techniques, GC‐MS confirmed data obtained via TLC for mono‐ to trisaccharides, delivering additionally quantified values under a considerable amount of time. A carbohydrate of higher oligomerisation degree could not be found. The application of mf‐MELDI‐MS further confirmed the presence of carbohydrates up to trisaccharides, also hinting at the presence of a form of tetrasaccharide. Besides this information, mf‐MELDI‐MS delivered further data about other substances present in the extract. Quantitative determination resulted in 1.750, 1.736 and 0.336 mg/mL for glucose, sucrose and raffinose respectively.Conclusion – Evaluation of all three techniques employed, clearly proved the heightened performance of mf‐MELDI‐MS for the qualitative analysis of complex mixtures, as targets do not need modification and analysis requires only a few minutes. In addition, GC‐MS is suitable for quantitative analysis. Copyright © 2011 John Wiley & Sons, Ltd.
Design, synthesis and characterization of a peptide able to bind proteins of the KCTD family: implications for KCTD—cullin 3 recognition
Authors: Pirone Luciano , Correale Stefania , Paola Ivan de , Zaccaro Laura , Simone Giuseppina De , Vitagliano Luigi , Pedone Emilia , Gaetano Sonia Di 
Published: March 2011

AbstractPox virus Zinc/Bric‐à‐brac, Tramtrack and Broad (POZ/BTB) is a widespread domain detected in proteins involved in a variety of biological processes. Human genome analyses have unveiled the presence of POZ/BTB domain in a class of proteins (KCTD) whose role as important players in crucial biological processes is emerging. The development of new molecular entities able to interact with these proteins and to modulate their activity is a field of relevant interest. By using molecular modeling and literature mutagenesis analyses, we here designed and characterized a peptide that is able to interact with submicromolar affinities with two different members (KCTD11 and KCTD5) of this family. This finding suggests that the tetrameric KCTD11 and the pentameric KCTD5 are endowed with a similar cavity at the subunit–subunit interface deputed to the Cul3 binding, despite their different oligomeric states. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.
ENVIRONMENTAL DETERMINANTS OF WATER QUALITY IN BOREAL RIVERS BASED ON PARTITIONING METHODS
Authors: Varanka S. , Luoto M. 
Published: March 2011

ABSTRACTQuantitative studies of the relationships between river water quality and environmental variables are needed to improve understanding of the impacts of natural and human factors on aquatic environments. However, multicollinearity between environmental variables can hinder the identification of key factors when water quality–environment relationship is studied using traditional regression methods. This study utilized two alternative statistical methods, variation and hierarchical partitioning, to address these difficulties in studies of river water quality. Using these methods, we explored the effects of catchment physiography, climate and land use variables on total phosphorus and nitrogen, pH, water colour and dissolved oxygen during the years 1995–2005 in 32 boreal rivers in Finland.Catchment physiography and land use explained most of the variation in water quality, especially in phosphorus, nitrogen and water colour data. The strong correlations (rs > 0.8) between agricultural land use and phosphorus and nitrogen concentrations indicate that water quality is highly affected by agriculture in boreal regions. By determining the environmental drivers of different water quality variables, we can estimate the water quality of different catchments in response to environmental changes and identify areas that are sensitive to global changes. Our study shows that novel statistical methods integrated with geographic information system data and techniques provide deeper insights into water quality–environment relationships than traditional regression, and these should be considered when developing, for example, conservation planning for rivers. Copyright © 2011 John Wiley & Sons, Ltd.
Linearity of the instrumental intensity scale in TOF‐SIMS—a VAMAS interlaboratory study
Authors: Lee J. L. S. , Gilmore I. S. , Seah M. P. 
Published: March 2011

AbstractA VAMAS interlaboratory study involving 21 time‐of‐flight SIMS instruments from nine countries has been conducted to evaluate the linearity of the instrumental intensity scale and procedures for intensity correction. Analysts were supplied, by National Physical Laboratory (NPL), with a protocol for analysis (closely aligned with ISO 23830) together with a reference material of polytetrafluoroethylene (PTFE) tape. The primary ion beam current is varied to provide secondary ion intensities that span the linear to nonlinear regime. The natural carbon isotope ratios 12CxFy+/13C12Cx−1Fy+ for five peaks are used to evaluate the linearity, without a need to measure the ion beam current. A method is given for determining the linearity as a function of secondary ion intensity, with and without dead time correction. It is found that single ion counting statistics is closely obeyed, and the linearity achievable is generally excellent with careful application of dead time correction. Three quarters of instruments in the study achieved better than 95% linearity at a count rate of 0.8 measured counts per pulse, equivalent to 1.6 secondary ions impinging the detector per primary ion pulse. We discuss factors affecting linearity and the precise application of dead time correction and give guidance for practical analysis. This includes suboptimal detector efficiency, inhomogeneous intensities across the rastered area, inadequate charge compensation, and the choice of peak integration limits. The interlaboratory study shows that the method to determine linearity is generally applicable, robust and provides an excellent basis for the development of an ISO standard. © Crown copyright 2011. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.
In‐Situ Measurement of CO‐ and CO2‐Concentrations in BOF Off‐Gas
Authors: Sandlöbes S. , Senk D. , Sancho L. , Diaz A. 
Published: March 2011

AbstractImprovement of the efficiency and productivity of steelmaking requires accurate and real‐time process information to precisely adjust the tapping conditions. The response time of BOF process control systems is commonly depending on the time needed for off‐gas sampling and analysis.A FTIR based measurement system was adapted and installed at an industrial steel converter of ArcelorMittal España S.A. in Aviles. An advanced data interpretation routine based on the quantum mechanical fundamentals of remote infrared (IR) spectroscopy was developed to enable precise determination of the {CO}‐ and {CO2}‐concentrations, resp. their ratio, in the off‐gas.The results of the industrial measurement showed the ability of the FTIR based system for real‐time measurement of temperature, {CO}‐ and {CO2}‐concentrations in the hot and dusty off‐gas. The influence of dust at the chosen defined optical path lengths in the IR wavelengths region can be neglected, but the collector lens clean has to be kept clean.
Polynomial approximation to universal ionisation cross‐sections of K and L shells induced by H and He ion beams
Authors: Taborda A. , Chaves P. C. , Reis M. A. 
Published: March 2011

AbstractIn 1970s, Basbas et al.(Phys. Rev. A 1973, 7, 983; Phys. Rev. A 1978, 17, 1655) rose the possibility that PWBA ionisation cross‐sections could be expressed in terms of a universal ionisation cross‐section. Starting from ECPSSR ionisation cross‐sections and reproducing Basbas approach, a universal curve can be displayed against the reduced ion velocity, but data are too widespread to allow for a proper polynomial fit. In the present work, Basbas approach was revised and plotted against a rescaled, reduced ion velocity, eliminating most of the data spread and generating in practice a universal ionisation cross‐section curve. In this revised approach, the screening parameter, θn, o, assumes a major role in reaching the universal behaviour. Polynomial approximations are then made to the universal curves for incident H+ and He2+ ions. Cross‐sections were then calculated using the polynomial approximations for target elements with atomic number from 11 to 92 and for ion beam energies from 50 keV to 10 MeV, for K‐ and L‐shell ionisation cross‐sections and are compared to experimental data from literature. Finally, X‐ray yields were simulated for various thick target samples using these polynomial approximations and the outcomes are compared to data obtained at the ITN PIXE set‐up. Copyright © 2011 John Wiley & Sons, Ltd.
Pentamethylcyclopentadienyl(η6‐cyclooctatrienyl)ruthenium Tetrachlorozincate, [RuCp*(η6‐C8H10)]2ZnCl4
Authors: Bruce Michael I. , Joly Damien , Skelton Brian W. , White Allan H. 
Published: March 2011

AbstractThe crystal and molecular structures of the title compound, the first for a complex of the type [RuCp*(η6‐C8‐ring)]+, is presented, the material being obtained serendipitously from a reaction between RuCl(cod)Cp* and 1‐ferrocenylbuta‐1,3‐diyne in the presence of ZnCl2. <Ru‐C(Cp*)> (2.21 Å) is appreciably longer than in RuCp*2 (2.18 Å) and similar to the value for the Ru‐η6 component (2.22 Å).
Gemischte Tristannide der Reihe CaSn3 – SrSn3 – BaSn3: Synthesen, Kristallstrukturen, Chemische Bindung
Authors: Wendorff Marco , Röhr Caroline 
Published: March 2011

AbstractTernary mixed Ca/Sr/Ba tristannides of overall composition ASn3 (A = Ca, Sr, Ba) were synthesized from mixtures of the elements. The structures of the compounds were determined by means of single‐crystal X‐ray data or Rietveld powder refinements. All structures exhibit close packed ordered ASn3 layers containing Sn Kagomé nets, which are stacked in different orientations. Depending on the stacking sequences, the resulting tin polyanion resembles the oxygen nets of the cubic (corner sharing octahedra, c stacking, Cu3Au‐type structure, i.e. CaSn3) or of the hexagonal perovskites (face sharing octahedra, h stacking, Ni3Sn‐type structure, i.e. BaSn3). In the binary compound CaSn3 (Cu3Au‐type) up to 46(5) % of calcium can be substituted against strontium (cubic, space group Pm$\bar{3}$m, a = 479.75(3), Z = 1, RP = 0.0587, RBragg = 0.0343). The known binary phase SrSn3 forms the Mg3In structure type with a (hhcc)3 stacking sequence and exhibits no noticeable phase width. A small partial substitution of strontium, against barium (Sr0.91(2)Ba0.09(2)Sn3 to Sr0.81(2)Ba0.19(2)Sn3: trigonal, space group R$\bar{3}$m, a = 698.9(2)/701.21(14), c = 2472.4(10)/2465.0(7) pm, Z = 9, R1 = 0.0637/0.0738) causes the packing to switch to the (hhc)3 stacking of the TaCo3‐type structure. At a Ba proportion of 26(2) % (Sr0.74(2)Ba0.26(2)Sn3: hexagonal, space group P63/mmc, a = 704.21(12), c = 2197.6(5) pm, Z = 8, R1 = 0.0705) a further structure change to the BaSn2.57Bi0.43 structure type ((hhhc)2‐stacking) occurs. The series is terminated with the pure h stacking of BaSn3, the stability range of which starts at the composition Sr0.22(2)Ba0.78(2)Sn3 (hexagonal, space group P63/mmc; a = 717.92(12), c = 548.15(10) pm, Z = 2, R1 = 0.0297). As easily noted from this series, the stacking sequence depends on the ratio of the atomic radii of the contributing atoms/ions. The observed trend can be rationalized by the decreasing coordination number of tin when going from c to h stacking. Covalent as well as metallic aspects of the chemical bonding in the tristannides are discussed on the basis of the results of FP‐LAPW calculations (density of states, band structure and valence electron densities).
Long‐Term Administration of Cod Liver Oil Ameliorates Cognitive Impairment Induced by Chronic Stress in Rats
Authors: Trofimiuk Emil , Braszko Jan J. 
Published: March 2011

AbstractCod liver oil (CLO) is a rich source of omega‐3 fatty acids (FA), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The existing data suggest that EPA and DHA are the active agents of fish oil. In this study, we tested a hypothesis that the active constituents of CLO alleviate the negative impact of prolonged restraint stress on cognitive functions of male Wistar rats. Specifically, we attempted to characterize the preventive action of long‐lasting treatment with CLO [0.375 ml/100 g body weight (equivalent to a dose of 300 mg/kg DHA and 225 mg/kg EPA), p.o. for 21 days] against an impairment caused by chronic restraint stress (2 h daily for 21 days) on recall as tested in a passive avoidance situation and on the spatial reference and working memory tested in a Barnes maze as well as on locomotor activity and anxiety behavior tested respectively in an open field and elevated plus‐maze. We found that CLO administration statistically significantly (p < 0.01, both) prevented the deleterious effects of chronic restraint stress on recall and the spatial memory.
Oxidation of Crude Corn Oil with and without Elevated Tocotrienols
Authors: Dolde David , Wang Tong 
Published: March 2011

AbstractKernels and oil from corn with increased concentrations of tocotrienols (T3) due to the transgenic expression of a homogentisic acid geranylgeranyl transferase (HGGT) gene from two growing years were characterized for tocol and fatty acid compositions. The crude extracted oil was analyzed for oxidative properties and compared to non‐transformed material derived from the plants grown at the same location and during the same year. No significant difference was observed in composition of major fatty acids. Both the seed (kernel) and extracted crude oil from the HGGT expressing corn had a 18‐fold increase in tocotrienol content from 300 to 5,400 ppm in oil. There was a concurrent 18% decrease in tocopherol content, 1,150 ppm total tocopherols in control oil declining to 940 ppm in HGGT oil. Although tocopherols and tocotrienols are generally considered antioxidants, they may exhibit prooxidant effects at higher concentrations and they should be tested. Crude oil was extracted from control and transformed corn produced during 2005 and 2006 yielding four oil samples that were evaluated for their oxidative properties. The formation of lipid hydroperoxides, a primary oxidation product, was evaluated at 60 °C over 9 days by measuring the peroxide value (PV). Resistance to oxidation or induction period (IP) was measured using an Oxidative Stability Instrument. There was a slight decrease in hydroperoxide formation in the HGGT oil compared to the corresponding control but was less than the year to year differences. The induction period was the same for the 2005 oils, with or without the increased tocotrienol content, but the crude oil with enhanced tocotrienol had a longer IP than the control crude oil in the 2006 samples.
In vitro experiments reconstituting topographic map formation
Authors: Gebhardt C. , Weth F. , Bastmeyer M. 
Published: March 2011

Abstract
Topographic axonal projections are a prev­alent feature of brain connectivity. The ret­inotectal mapping of the chick is the best-studied model system of this type of neuro­nal connectivity. Its formation is common­ly explained by interactions between grad­ed markers of the ephrin-A/EphA family ex­pressed on both retinal ganglion cell growth cones and on the tectal target area. Surpris­ingly, most insights into retinotectal devel­opment have been gathered through in vitro rather than in vivo experiments. In vitro as­says not only enabled the biochemical iden­tification of the postulated molecular mark­ers but also helped to understand the signals conveyed by them. Thus, it was established in vitro that forward (ephrin-A->EphA) as well as reverse signalling (EphA->ephrin-A) are si­multaneously needed for topographically ap­propriate guidance of retinal axons. However, no in vitro assay yet exists that fully reproduc­es topography formation. New in vitro tech­niques such as micro-contact printing or mi­cro-fluidic networks may help to improve ex­istent assays and to identify a sufficient set of functional components that reconstitutes to­pography formation.
ASSESSING THE RISK OF ROOT ROTS IN COMMON BEANS IN EAST AFRICA USING SIMULATED, ESTIMATED AND OBSERVED DAILY RAINFALL DATA
Authors: FARROW ANDREW , MUSONI DIDACE , COOK SIMON , BURUCHARA ROBIN 
Published: March 2011

SUMMARYThis paper seeks to establish the concept that the analysis of high temporal resolution meteorological data adds value to the investigation of the effect of climatic variability on the prevalence and severity of agricultural pests and diseases. Specifically we attempt to improve disease potential maps of root rots in common beans, based on a combination of inherent susceptibility and the risk of exposure to critical weather events. We achieve this using simulated datasets of daily rainfall to assess the probability of heavy rainfall events at particular times during the cropping season. We then validate these simulated events with observations from meteorological stations in East Africa. We also assess the utility of remotely sensed daily rainfall estimates in near real time for the purposes of updating the risks of these events over large areas and for providing warnings of potential disease outbreaks. We find that simulated rainfall data provide the means to assess risk over large areas, but there are too few datasets of observed rainfall to definitively validate the probabilities of heavy rainfall events generated using rainfall simulations such as those generated by MarkSim. We also find that selected satellite rainfall estimates are unable to predict observed rainfall events with any power, but data from a sufficiently dense network of rain gauges are not available in the region. Despite these problems we show that remotely sensed rainfall estimates may provide a more realistic assessment of rainfall over large areas where rainfall observations are not available, and alternative satellite estimates should be explored.