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Cadmium and lead toxicity and bioaccumulation in Microcystis aeruginosa

Frontiers of Environmental Science & Engineering 2014年第3期8卷 427-432页

作者： Piotr RZYMSKI barbara PONIEDZIALEK Przemyslaw NIEDZIELSKI Piotr TABACZEWSKI Krzysztof WIKTOROWICZ Department of Biology and Environmental Protection Poznan University of Medical Sciences Poznan 61-848 Poland Faculty of Chemistry Department of Water and Soil Analysis Adam Mickiewicz University Poznan 61-614 Poland

The growth of human population leads to intensification of agriculture and promotes, through eutrophication, development of cyanobacteria. One of the most widespread and bloom-forming species in freshwater is toxic Microcystis aeruginosa （M. aeruginosa）. Combustion of fossil fuels and metallurgical processes are the main sources of heavy metals contamination in surface water including cadmium （Cd） and lead （Pb）. The following study was conducted in order to determine the effect of 1- 20 mg. L-1 of Cd and Pb on photochemistry （using flow cytometry） and growth （based on chlorophyll concentra- tion） ofM. aeruginosa as well as to estimate levels of metal bioaccumulation. We have found that 1-10mg.L-1 of Cd and 1-5 rag. L1 of Pb induced continuous enhancement of chlorophyll fluorescence during 24 h of incubation. No significant degradation of chlorophyll was observed in these samples. At higher concentrations of 20 mg. L-1 of Cd and 10-20 mg.L-1 of Pb chlorophyll level significantly decreased and its fluorescence was quenched. M. aeruginosa demonstrated high capability of Cd and Pb bioaccumulation, proportionally to initial metal concentration. In samples with initial concentration of 20 mg. L-1 of Cd and Pb bioaccumulation of 87.3% and 90.1% was observed, respectively. Our study demonstrates that M. aeruginosa can potentially survive in highly metals polluted environments, be a primary source of toxic metals in the food chain and consequently contribute to enhanced toxicity of heavy metals to living organisms including human.

关键词： Microcystis aeruginosa heavy metals bioac-cumulation chlorophyll flow cytometry

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Therapeutic potential of small interfering RNAs/micro interfering RNA in hepatocellular carcinoma

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World Journal of Gastroenterology 2015年第30期21卷 8994-9001页

作者： Rossella Farra Mario Grassi Gabriele Grassi barbara Dapas Department of Industrial Engineering and Information Technology University of Trieste Department of Life Sciences University of Trieste Department of ‘‘Scienze Mediche Chirurgiche e della Salute’’University of TriesteCattinara Hospital

Hepatocellular carcinoma(HCC) is the predominant form of primary liver cancer and represents the third leading cause of cancer-related death worldwide. Current available therapeutic approaches are poorly effective,especially for the advanced forms of the disease. In the last year,short double stranded RNA molecules termed small interfering RNAs(si RNAs) and micro interfering RNAs(mi RNA),emerged as interesting molecules with potential therapeutic value for HCC. The practical use of these molecules is however limited by the identification of optimal molecular targets and especially by the lack of effective and targeted HCC delivery systems. Here we focus our discussion on the most recent advances in the identification of si RNAs/mi RNAs molecular targets and on the development of suitable si RNA/mi RNAs delivery systems.

关键词： Small interfering RNA Micro interferingRNA Delivery Hepatocellular carcinoma Therapeuticpotential

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Liver fibrosis and tissue architectural change measurement using fractal-rectified metrics and Hurst's exponent

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World Journal of Gastroenterology 2006年第14期12卷 2187-2194页

作者： Nicola Dioguardi Fabio Grizzi barbara Franceschini Paola Bossi Carlo Russo Laboratori di Medicina Quantitativa Istituto Clinico Humanitas IRCCS RozzanoMilanand "Michele Rodriguez" FoundationInstitute for Quantitative Methods in MedicineMilanItaly Department of Pathology Istituto Clinico Humanitas IRCCS RozzanoMilanItaly

AIM： To provide the accurate alternative metrical means of monitoring the effects of new antiviral drugs on the reversal of newly formed collagen. METHODS： Digitized histological biopsy sections taken from 209 patients with chronic C virus hepatitis with different grade of fibrosis or cirrhosis, were measured by means of a new, rapid, user-friendly, fully computeraided method based on the international system meter rectified using fractal principles. RESULTS： The following were described： geometric perimeter, area and wrinkledness of fibrosis; the collation of the Knodell, Sheuer, Ishak and METAVIR scores with fractal-rectified metric measurements; the meaning of the physical composition of fibrosis in relation to the magnitude of collagen islets; the intra- and inter-biopsy sample variability of these parameters; the ＂staging＂ of biopsy sections indicating the pathway covered by fibrosis formation towards its maximum known value; the quantitative liver tissue architectural changes with the Hurst exponent. CONCLUSION： Our model provides the first metrical evaluations of the geometric properties of fibrosis and the quantitative architectural changes of the liver tissue. The representativeness of histological sections of the whole liver is also discussed in the light of the results obtained with the Hurst coefficient.

关键词： Liver Fibrosis Cirrhosis Staging Image analysis Fractals

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Chromium Content in the Human Hip Joint Tissues

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Biomedical and Environmental Sciences 2015年第2期28卷 89-96页

作者： barbara Brodziak-Dopiera?a Jerzy Kwapuliński Krzysztof Sobczyk Danuta Wiechu?a School of Pharmacy with the Division of Laboratory Medicine Department of Toxicology Medical University of Silesia Institute of Occupational Medicine and Environmental Health Municipal Hospital Department of Traumatic Surgery

Objective Chromium has many important functions in the human body. For the osseous tissue, its role has not been clearly defined. This study was aimed at determining chromium content in hip joint tissues. Methods A total of 91 hip joint samples were taken in this study, including 66 from females and 25 from males. The sample tissues were separated according to their anatomical parts. The chromium content was determined by the AAS method. The statistical analysis was performed with U Mann-Whitney＇s non-parametric test, P〈0.05. Results The overall chromium content in tissues of the hip joint in the study subjects was as follows： 5.73 μg/g in the articular cartilage, 5.33 μ/g in the cortical bone, 27.86 μ/g in the cancellous bone, 5.95 μg/8 in the fragment of the cancellous bone from the intertrochanteric region, and 2.28 μ/g in the joint capsule. The chromium contents were observed in 2 group patients, it was 7.04 μ/g in people with osteoarthritis and 22.59 μ/g in people with fractures. Conclusion The observed chromium content was highest in the cancellous bone and the lowest in the joint capsule. Chromium content was significantly different between the people with hip joint osteoarthritis and the people with femoral neck fractures.

关键词： Chromium Femur head Hip joint Cortical bone Cancellous bone

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MEF13 Requires MORF3 and MORF8 for RNA Editing at Eight Targets in Mitochondrial mRNAs in Arabidopsis thaliana

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Molecular Plant 2015年第10期8卷 1466-1477页

作者： Franziska Glass barbara Hartel Anja Zehrmann Daniil Verbitskiy Mizuki Takenaka Molekulare Botanik Universitat UIm 89069 UIm Germany These authors contributed equally to this article.

RNA editing sites in plant mitochondria and plastids are addressed by pentatricopeptide repeat （PPR） proteins with E or E and DYW domains, which recognize a specific nucleotide motif upstream of the edited nucleotide. In addition, some sites require MORF proteins for efficient RNA editing. Here, we assign the novel E domain-containing PPR protein, MEF13, as being required for editing at eight sites in Arabidopsis thaliana. A SNP in ecotype C24 altering the editing level at only one of the eight target sites was located by genomic mapping. An EMS mutant allele of the gene for MEF13 was identified in a SNaPshot screen of a mutated plant population. At all eight target sites of MEF13, editing levels are reduced in both morf3 and morf8 mutants, but at only one site in morfl mutants, suggesting that specific MEF13-MORF interactions are required. Yeast two-hybrid analyses detect solid connections of MEF13 with MORF1 and weak contact with MORF3 proteins. Yeast three-hybrid （Y3H） analysis shows that the presence of MORF8 enhances the connection between MEF13 and MORF3, suggesting that a MORF3-MORF8 heteromer may form stably or transiently to establish interaction with MEF13.

关键词： RNA editing plant mitochondria PPR protein MEF13 MEF-MORF interaction

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Bile-acid-activated farnesoid X receptor regulates hydrogen sulfide production and hepatic microcirculation

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World Journal of Gastroenterology 2009年第17期15卷 2097-2108页

作者： barbara Renga Andrea Mencarelli Marco Migliorati Eleonora Distrutti Stefano Fiorucci Department of Clinical and Experimental Medicine University of Perugia Via E dal Pozzo 06122 Perugia Italy Azienda Ospedaliera di Perugia Ospedale Santa Maria della Misericordia 06122 Perugia Italy

AIM: To investigate whether the farnesoid X receptor (FXR) regulates expression of liver cystathionase (CSE), a gene involved in hydrogen sulfi de (H2S) generation. METHODS: The regulation of CSE expression in response to FXR ligands was evaluated in HepG2 cells and in wild-type and FXR null mice treated with 6-ethyl chenodeoxycholic acid (6E-CDCA), a synthetic FXR ligand. The analysis demonstrated an FXR responsive element in the 5'-flanking region of the human CSE gene. The function of this site was investigated by luciferase reporter assays, chromatin immunoprecipitation and electrophoretic mobility shift assays. Livers obtained from rats treated with carbon tetrachloride alone, or in combination with 6-ethyl chenodeoxycholic acid, were studied for hydrogen sulphide generation and portal pressure measurement. RESULTS: Liver expression of CSE is regulated by bile acids by means of an FXR-mediated mechanism. Western blotting, qualitative and quantitative polymerase chain reaction, as well as immunohistochemical analysis, showed that expression of CSE in HepG2 cells and in mice is induced by treatment with an FXR ligand. Administration of 6E-CDCA to carbon tetrachloride treated rats protected against the down-regulation of CSE expression, increased H2S generation, reduced portal pressure and attenuated the endothelial dysfunction of isolated and perfused cirrhotic rat livers. CONCLUSION: These results demonstrate that CSE is an FXR-regulated gene and provide a new molecular explanation for the pathophysiology of portal hypertension.

关键词： Nuclear receptor Farnesoid X receptor Cystathionase Hydrogen sulfide Portal hypertension

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Towards Textbook Efficiency for Parallel Multigrid

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Numerical Mathematics(Theory,Methods and Applications) 2015年第1期8卷 22-46页

作者： Bjorn Gmeiner Ulrich Rude Holger Stengel Christian Waluga barbara Wohlmuth Institute for Numerical Mathematics(M2) Technische Universitat MunchenBoltzmannstrasse 3D-85748 Garching b.MünchenGermany Department of Computer Science 10 FAU Erlangen-NürnbergCauerstraße 6D–91058 ErlangenGermany Erlangen Regional Computing Center(RRZE) FAU Erlangen-NürnbergMartensstraße 1D–91058 ErlangenGermany

In this work,we extend Achi Brandt’s notion of textbook multigrid effi-ciency(TME)to massively parallel *** a finite element based geomet-ric multigrid implementation,we recall the classical view on TME with experiments for scalar linear equations with constant and varying coefficients as well as linear systems with saddle-point *** extend the idea of TME to the parallel set-ting,we give a new characterization of a work unit(WU)in an architecture-aware fashion by taking into account performance modeling *** illustrate our newly introduced parallel TME measure by large-scale computations,solving prob-lems with up to 200 billion unknowns on a TOP-10 supercomputer.

关键词： Multigrid parallel computing textbook efficiency finite element method

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Earth observation in service of the 2030 Agenda for Sustainable Development

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Geo-Spatial Information Science 2017年第2期20卷 77-96页

作者： Katherine Anderson barbara Ryan William Sonntag Argyro Kavvada Lawrence Friedl Group on Earth Observations GenevaSwitzerland Booz Allen Hamilton WashingtonDCUSA NASA Earth Science Division WashingtonDCUSA

This paper reviews the key role that Earth Observations(EO)play in achieving the Sustainable Development Goals(SDGs)as articulated in the 2030 Agenda document and in monitoring,measuring,and reporting on progress towards the associated *** paper also highlights how the Group on Earth Observations(GEO)would contribute to ensure the actual use of EO in support of the 2030 Agenda;and how the Global Earth Observations System of Systems meets requirements for efficient investments in science and technology and a good return on investment,which is elaborated in the Addis Ababa Action Agenda on development *** a number of examples,we first discuss how extensive EO use would:provide a substantial contribution to the achievements of the SDGs by enabling informed decision-making and by allowing monitoring of the expected results;improve national statistics for greater accuracy,by ensuring that the data are“spatially-explicit”and directly contribute to calculate the agreed SDG Targets and Indicators support the fostering of synergy between the SDGs and multilateral environmental agreements by addressing cross-cutting themes such as climate and energy;and facilitate countries’approaches for working across different development sectors,which is,according to the special adviser on the 2030 Agenda,a key challenge to achieve the *** then focus on the role that GEO could play in enabling actual use of EO in support of the 2030 Agenda by directly addressing the Strategic Development Goal 17 on partnerships.

关键词： Earth observation Group on Earth Observations(GEO) Sustainable Development Goal(SDG) the 2030 Agenda

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Photoluminescence and energy transfer in transparent glass-ceramics based on GdF3:RE3+（RE=Tb,Eu）nanocrystals

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Journal of Rare Earths 2019年第11期37卷 1137-1144页

作者： Natalia Pawlik barbara Szpikowska-Sroka Ewa Pietrasik Tomasz Goryczka Wojciech A.Pisarski Institute of Chemistry University of Silesia9 Szkolna StreetKatowice 40-007Poland Institute of Materials Science University of Silesia75 Putku Piechoty 1A StreetChorzow 41-500Poland

In the present work,the transparent oxyfluoride glass-ceramic samples containing GdF3:RE^3+(RE=Tb,Eu)nanocrystals(nGCs)were fabricated via controlled heat-treatment of precursor xerogels prepared using a sol-gel *** formation of GdF3 nanocrystalline phase from gadolinium(III)trifluoroacetate was verified based on XRD *** average crystal sizes calculated from Scherrer formula were estimated to^10 nm as well as^6 nm for Tb^3+-and Eu^3+-doped samples,*** optical behavior of prepared sol-gel samples was evaluated based on photoluminescence excitation(PLE)and emission spectra(PL)as well as luminescence decay *** samples exhibit the 5D4→7FJ(J=6-3,Tb3+)and the 5D0→7FJ(J=0-4,Eu3+)emission bands recorded within the visible spectral area under excitation at near-UV(393 nm(Eu^3+),351,369,378 nm(Tb^3+))as well as middle-UV illumination(273 nm(Gd3+)).Additionally,based on recorded decay curves,the luminescence lifetimes(τm)for the 5D4(Tb^3+)and the 5D0(Eu3+)excited states were also *** general,recorded luminescence spectra and double-exponential character of decay curves for nGCs indicate a successful migration of Tb^3+and Eu^3+dopant ions from amorphous silicate framework to lowphonon energy GdF3 nanocrystal phase.

关键词： Sol-gel method GdF3 nanocrystals Terbium Europium Rare earths

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Commentary on “Does light-intensity physical activity moderate the relationship between sitting time and adiposity markers in adolescents?”

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Journal of Sport and Health Science 2024年第4期13卷 453-454页

作者： barbara E.Ainsworth Amanda M.Ferland School of Exercise and Health Shanghai University of SportShanghai 200433China Department of Orthopedics Tongji UniversityShanghai 200092China

In the September 2022 issue of the Journal of Sport and Health Science,Ayala et al.1 published results from a cross-sectional study where they tested the hypothesis that light intensity physical activity(LIPA,1.6-2.9 metabolic equivalents(METs))moderates the relationship between sitting time and adiposity in 219 Australian adolescents aged 14±1.6 years(mean±SD).

关键词： metabolic light

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