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Biochar Serves as a Long-term Soil carbon Pool

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地学前缘 2009年第S1期16卷 231-232页

作者： lena Q.Ma Soil and Water Science Department University of Florida

Biochar is a carbon-rich(>60%)organic material derived from incomplete combustion of fossil fuels and *** consists of a continuum ranging from slightly charred material through char and charcoal to soot,and is ubiquitous in the atmosphere,marine sediment,soil and ***,>80%of biochar produced ends up in soils,where it resides for hundreds to thousands of *** of its resistance to biological and chemical breakdown, biochar can serve as a pool of c with long residence time in the *** a result,there has been increasing attention given to the potential of biochar to sequestrate carbon and counteract

关键词： biochar soil carbon pool carbon-based greenhouse gases

Toxic effects of crude-oil-contaminated soil in aquatic environment on carassius auratus and their hepatic antioxidant defense system

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Journal of Environmental Sciences 2009年第5期21卷 612-617页

作者： WANG Yuanyuan ZHOU Qixing PENG Shengwei MA lena Q NIU Xiaowei Key Laboratory of Pollution Processes and Environmental criteria (Ministry of Education of china) College of Environmental Science and Engineering Nankai University Tganjin 300071 China Soil and Water Science Department University of Florida Gainesville FL 32611-0290 USA

Under the indoor simulant conditions, toxic effects of crude-oil-contaminated soil which was put into aquatic environment on the young fishes carassius auratus and their hepatic antioxidant system after a 20-d exposure were investigated. Results showed that the relationship between the mortality of c. auratus and the exposed doses could be divided into 3 phases： fishes exposed to the low dose groups （0.5-5.0 g/L） were dead due to the ingestion of crude-oil-contaminated soils in aquatic environment; at the medium dose groups （5.0-25.0 g/L） fishes were dead due to the penetration of toxic substances; at the high dose groups （25.0-50.0 g/L） fishes were dead due to environmental stress. The highest mortality and death speed were found in the 1.0 g/L dose group, and the death speed was sharply increased in the 50.0 g/L dose group in the late phase of exposure. The activities of superoxide dismutase （SOD）, catalase （cAT） and glutathione S-transferase （GST） and the content of malaondialdehyde （MDA） in the hepatic tissues of c. auratus were induced significantly. The activity of SOD was increased and then decreased. It was significantly inhibited in the 50.0 g/L dose group. The activity of cAT was highly induced, and restored to a level which is little more than the control when the exposed doses exceeded 10.0 g/L. The activity of GST was the most sensitive, it was significantly induced in all dose groups, and the highest elevation was up to 6 times in the 0.5 g/L dose group comparing with the control. The MDA content was significantly elevated in the 50.0 g/L dose group, and the changes of the MDA content were opposite with the changes of GST activity.

关键词： crude-oil-contaminated soil ecotoxicology aquatic environment carassius auratus antioxidant defense system

Long-term effects of environmentally relevant concentrations of silver nanoparticles on microbial biomass, enzyme activity,and functional genes involved in the nitrogen cycle of loamy soil

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Journal of Environmental Sciences 2018年第7期30卷 12-22页

作者： Anna-lena Grün Susanne Straskraba Stefanie Schulz Michael Schloter christoph Emmerling Faculty of Regional and Environmental Sciences Department of Soil Science University of Trier J.W.Goethe University Institute of Molecular Biosciences Research for comparative Microbiome Analysis Helmholtz Zentrum München chair for Soil Science Technische Universit?t München

The increasing production and use of engineered silver nanoparticles（AgNP） in industry and private households are leading to increased concentrations of AgNP in the environment. An ecological risk assessment of AgNP is needed, but it requires understanding the long term effects of environmentally relevant concentrations of AgNP on the soil microbiome. Hence, the aim of this study was to reveal the long-term effects of AgNP on soil microorganisms. The study was conducted as a laboratory incubation experiment over a period of one year using a loamy soil and AgNP concentrations ranging from 0.01 to 1 mg AgNP/kg soil. The short term effects of AgNP were, in general, ***, after one year of exposure to 0.01 mg AgNP/kg, there were significant negative effects on soil microbial biomass（quantified by extractable DNA; p = 0.000） and bacterial ammonia oxidizers（quantified by amo A gene copy numbers; p = 0.009）. Furthermore, the tested AgNP concentrations significantly decreased the soil microbial biomass, the leucine aminopeptidase activity（quantified by substrate turnover; p = 0.014）, and the abundance of nitrogen fixing microorganisms（quantified by nif H gene copy numbers; p = 0.001）. The results of the positive control with Ag NO3 revealed predominantly stronger effects due to Ag＋ion release. Thus, the increasing toxicity of AgNP during the test period may reflect the long-term release of Ag^＋ions. Nevertheless, even very low concentrations of AgNP caused disadvantages for the microbial soil community, especially for nitrogen cycling, and our results confirmed the risks of releasing AgNP into the environment.

关键词： Silver nanoparticles Soil Microbiome amoA nifH Leucine aminopeptidase activity AgPure

Polarity,intramolecular charge transfer,and hydrogen bond comediated solvent effects on the optical properties of graphene quantum dots

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Nano Research 2023年第1期16卷 45-52页

作者： Yalei Hu christof Neumann lena Scholtz Andrey Turchanin Ute Resch-Genger Siegfried Eigler Institute of chemistry and Biochemistry Freie Universität BerlinTakustraße 314195 BerlinGermany Institute of Physical chemistry and Abbe center of Photonics Friedrich Schiller University JenaLessingstraße 1007743 JenaGermany Federal Institute for Materials Research and Testing(BAM) Division BiophotonicsRichard Willstätter Straße 1112489 BerlinGermany

Graphene quantum dots(GQDs)have attracted increasing attention due to their favorable optical properties and have been widely used,e.g.,in the biomedical ***,the properties related to the chemical structure of GQDs,resulting in solventdependent optical properties,still remain ***,we present the synthesis of long-wavelength emitting GQDs with a size of about 3.6 nm via a solvothermal method using oxo-functionalized graphene(oxo-G)and p-phenylenediamine as precursors and their structural and surface chemical analysis by transmission electron and atomic force microscopy(TEM;AFM)as well as Fourier-transform infrared,Raman,and X-ray photoelectron spectroscopy(FTIR;Raman;XPS).Subsequently,the influence of solvent polarity and proticity on the optical properties of the as-prepared GQDs bearing–OH,–NH_(2),–cOOH and pyridine surface groups was *** on the results of the absorption and fluorescence(FL)studies,a possible luminescence mechanism is *** observed solvent-induced changes in the spectral position of the FL maximum,FL quantum yield,and FL decay kinetics in protic and aprotic solvents of low and high polarity are ascribed to a combination of polarity effects,intramolecular charge transfer(IcT)processes,and hydrogen ***,the potential of GQDs for the optical sensing of trace amount of water was *** results of our systematic spectroscopic study will promote the rational design of GQDs and shed more light on the FL mechanism of carbon-based fluorescent nanomaterials.

关键词： graphene quantum dots(GQDs) polarity intramolecular charge transfer(IcT) hydrogen bond optical properties

Bcl-2 degradation is an additional pro-apoptotic effect of polo-like kinase inhibition in cholangiocarcinoma cells

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World Journal of Gastroenterology 2017年第22期23卷 4007-4015页

作者： Svenja Sydor Sami Jafoui lena Wingerter Sandra Swoboda Joachim c Mertens Guido Gerken Ali canbay Andreas Paul christian D Fingas Department of Gastroenterology and Hepatology University Hospital EssenUniversity Duisburg-Essen Department for General Visceral and Transplantation SurgeryUniversity Hospital EssenUniversity Duisburg-Essen Division of Gastroenterology and Hepatology University Hospital Zurich

To examine the influence on apoptotic mechanisms following inhibition of polo-like kinases as therapeutically approach for cholangiocellular cancer *** most cholangiocarcinomas are chemotherapy-resistant due to mechanisms preventing tumor cell death, we investigated the effect of cisplatin on cholangiocellular carcinoma (ccA) cell lines KMcH-1 and Mz-ch-1. Polo-like kinases (PLK) are important regulators of the cell cycle and their inhibition is discussed as a potential therapy while PLK inhibition can regulate apoptotic mediators. Here, cells were treated with PLK inhibitor BI6727 (Volasertib), cisplatin, and in combination of both compounds. cell viability was assessed by MTT; apoptosis was measured by DAPI staining and caspase-3/-7 assay. Western blot and qRT-PcR were used to measure expression levels of apoptosis-related molecules Bax and *** cell viability in the ccA cell lines KMcH-1 and Mz-ch-1 was reduced in all treatment conditions compared to vehicle-treated cells. co-treatment with BI6727 and cisplatin could even enhance the cytotoxic effect of cisplatin single treatment. Thus, co-treatment of cisplatin with BI6727 could slightly enhance the cytotoxic effect of the cisplatin in both cell lines whereas there was evidence of increased apoptosis induction solely in Mz-ch-1 as compared to KMcH-1. Moreover, PLK inhibition decreases protein levels of Bcl-2; an effect that can be reversed by the proteasomal degradation inhibitor MG-132. In contrast, protein levels of Bax were not found to be altered by PLK inhibition. These findings indicate that cytotoxic effects of cisplatin in Mz-ch-1 cells can be enhanced by cotreatment with *** conclusion, BI6727 treatment can sensitize ccA cells to cisplatin-induced apoptosis with proteasomal Bcl-2 degradation as an additional pro-apoptotic effect.

关键词： Tumor necrosis factor-related apoptosis-inducing ligand Myeloid cell leukemia-1 Hedgehog pathway cisplatin chemotherapy resistance

Intraoperative intracardiac thrombosis in a liver transplant patient

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World Journal of Hepatology 2010年第5期2卷 198-200页

作者： lena Sibulesky Prith Peiris c Burcin Taner David J Kramer Juan M canabal Justin H Nguyen Department of Transplantation Division of Transplant SurgeryMayo ClinicJacksonvilleFL 32224United States Department of Anesthesiology Mayo ClinicJacksonvilleFL 32224United States Departments of Trans-plantation and critical care Mayo ClinicJacksonvilleFL32224United States

A 66-year-old female with cryptogenic cirrhosis complicated by ascites,hepatic encephalopathy,variceal bleeding and malnutrition with MELD of 34 underwent orthotopic deceased donor liver transplantation performed with piggyback *** eversion thromboendovenectomy was performed for a portal vein thrombus which resulted in an excellent portal vein *** liver graft was recirculated without any hemodynamic ***,the patient became hypotensive progressing to *** was resuscitated and a transesophageal probe was inserted which revealed a mobile right atrial thrombus and an underfilled poorly contractile right *** patient was noted to be coagulopathic at the *** became progressively more stable with a TEE showing complete resolution of the intracardiac thrombus.

关键词： Liver transplantation cardiac thrombus Reperfusion injury coagulopathy Transesophageal echocardiogram

Treatment modalities for hypersplenism in liver transplant recipients with recurrent hepatitis c

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World Journal of Gastroenterology 2009年第40期15卷 5010-5013页

作者： lena Sibulesky Justin H Nguyen Ricardo Paz-Fumagalli c Burcin Taner Rolland c Dickson Division of Transplant Surgery and Transplant Hepatology Division of Interventional Radiology

Hepatitis c is the most common indication for orthotopic liver transplantation in the United States. Unfortunately, hepatitis c recurs universally in the transplanted liver and is the major cause of decreased graft and patient survival. The combination therapy of interferon and ribavirin has been shown to be the most effective therapy for recurrent hepatitis c. However, pre-and post-transplant hypersplenism often precludes patients from receiving the antiviral therapy. Splenectomy and partial splenic embolization are the two invasive modalities that can correct the cytopenia associated with hypersplenism. In this report we review the two treatment options, their associated outcomes and complications.

关键词： Hypersplenism Leukopenia Recurrenthepatitis c Thrombocytopenia Liver transplant

Dual Targeting to Mitochondria and chloroplasts： characterization of Thr-tRNA Synthetase Targeting Peptide

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Molecular Plant 2009年第6期2卷 1298-1309页

作者： Anna-Karin Berglund Erika Spanning Henrik Biverstahl Gianluca Maddalo christian Tellgren-Roth lena Maler Elzbieta Glaser Department of Biochemistry and Biophysics Arrhenius Laboratories for Natural Science Stockholm University SF-10691 Stockholm Sweden Department of Genetics and Pathology Rudbecklaboratoriet Uppsala University SE-751 85 Uppsala Sweden

There is a group of proteins that are encoded by a single gene, expressed as a single precursor protein and dually targeted to both mitochondria and chloroplasts using an ambiguous targeting peptide. Sequence analysis of 43 dual targeted proteins in comparison with 385 mitochondrial proteins and 567 chloroplast proteins ofArabidopsis thaliana revealed an overall significant increase in phenylalanines, leucines, and serines and a decrease in acidic amino acids and glycine in dual targeting peptides （dTPs）. The N-terminal portion of dTPs has significantly more serines than mTPs. The number of arginines is similar to those in mTPs, but almost twice as high as those in cTPs. We have investigated targeting determinants of the dual targeting peptide of Thr-tRNA synthetase （ThrRS-dTP） studying organellar import of N- and c-terminal deletion constructs of ThrRS-dTP coupled to GFR These results show that the 23 amino acid long N-terminal portion of ThrRS-dTP is crucial but not sufficient for the organellar import. The c-terminal deletions revealed that the shortest peptide that was capable of conferring dual targeting was 60 amino acids long. We have purified the ThrRS- dTP（2-60） to homogeneity after its expression as a fusion construct with GST followed by cNBr cleavage and ion exchange chromatography. The purified ThrRS-dTP（2-60） inhibited import of pF1β into mitochondria and of pSSU into chloroplasts at μM concentrations showing that dual and organelle-specific proteins use the same organellar import pathways. Furthermore, the cD spectra of ThrRS-dTP（2-60） indicated that the peptide has the propensity for forming α-helical structure in membrane mimetic environments; however, the membrane charge was not important for the amount of induced helical structure. This is the first study in which a dual targeting peptide has been purified and investigated by biochemical and biophysical means.

关键词： Dual targeting mitochondria chloroplast targeting peptide aminoacyl-tRNA synthetase

Effects of selective estrogen receptor agonists on estrogen receptor expression in the uterus of ovariectomized rats

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Open Journal of Molecular and Integrative Physiology 2012年第2期2卷 35-43页

作者： c. S. Blesson Britt Masironi lena Sahlin Division for Reproductive Endocrinology and the Pediatric Endocrinology Unit Department of Women’s and Children’s Health Karolinska Institutet Stockholm Sweden

The aim of the present study was to investigate effects of short time treatment with estrogen receptor (ER) selective agonists on ERα, ERβ and G-protein coupled estrogen receptor-1 (GPER) expression in the uterus of ovariectomized rats. The rats were treated with either estradiol (E2), the specific ERα agonist PPT or the specific ERβ agonist DPN for 18 hrs. Uterine weights were higher after E2 or PPT treatment than after DPN or no treatment. ERα mRNA levels decreased significantly in PPT and DPN treated animals as compared to controls. Stromal ERα immunostaining was higher after E2 treatment than in controls. The ERβ mRNA level was lower in the E2 and PPT groups compared with controls. ERβ immunoreactivity was higher in the myometrium after DPN treatment than in controls. The GPER mRNA level was lower in the E2 and DPN groups as compared to the controls, whereas total protein levels did not display any change. The proliferation marker Ki-67 increased after PPT treatment in stroma and myometrium, as compared to controls. Thus, uterine growth and proliferation are predominately regulated via ERα. Also ERβ expression showed regulation via ERα, while GPER expression indicated control via ERβ. This short term treatment did not result in any regulation of the total protein level as determined by Western blot. However, treatment by E2 increased ERα immunostaining in the stroma and DPN augmented ERβ immunostaining in the myometrium. Thus, the estrogen receptors in the rat uterus are differently regulated depending on the ligand and tissue type.

关键词： PPT DPN ERα ERβ GPER