Studies on milled wood lignin from spruce Part II. Electron microscopic observations on the milled wood

Summary Wood samples that had been ball-milled and extracted with dioxane under various conditions were observed in the scanning electron microscope. Ball milling causes not only a reduction in size of the cells and cell walls but also an internal disruption of the particles. The intensity of milling has a larger influence on the particle size than a prolongation of the milling time. A direct relation was established between particle size and the previously determined yield of purified milled wood lignin.Submitted by Erwin-Riesch-Stiftung zur Förderung der wissenschaftlichen Forschung.     

Environmental impact of energy crop cultivation

Crops cultivated as feedstock for energy conversion processes (energy crops) could cover about 5% of the total energy demand of the European Union. Therefore, cultivation, harvest, processing, and finally utilisation of feedstock are required to be sustainable minimising environmental pressures and maximising environmental benefits. This contribution will give a comprehensive view on the environmental impacts of cultivating conventional energy crop species like cereals, rape seed and maize and of the hitherto uncommon species such as willow and poplar. Generalisations of environmental relevant parameters are deduced based on literature surveys as well as on results from own long-term experiments at Leibniz-Institut für Agrartechnik institute. These parameters include biomass yield and energy yield, demand for water, fertiliser and pesticides as well as other environmentally relevant substances, emission of nitrous oxide and depletion and enrichment of soil carbon. In addition, recent results regarding energy balances and CO₂-balances are presented and discussed. It can be concluded that energy crops specified for ligno-cellulose utilisation are preferable to oil, sugar and starch containing crops. In the first case the whole plant biomass can be used. Furthermore, biodiversity is increased and nitrogen demand and nitrous oxide emissions are decreased. Finally, in context with conventional and especially future energy technologies it is possible to obtain high CO₂-mitigation potentials.

Energiepflanzen, also für die energetische Nutzung angebaute Kulturpflanzen, können ca. 5% des Energiebedarfs der Europäischen Union decken. Voraussetzung ist, dass Anbau, Ernte, Aufbereitung und die anschließende Nutzung dieser Pflanzen umweltverträglich erfolgen, d.h. negative Umweltwirkungen minimiert und positive maximiert werden. Der vorliegende Beitrag gibt einen Überblick über die Umweltwirkungen von konventionellen Energiepflanzen wie Getreide, Raps und Mais sowie bisher eher selten angebauten Arten wie Pappel und Weide. Auf Basis von Literaturrecherchen und langjährigen eigenen Untersuchungen werden verallgemeinerungsfähige Aussagen zu Biomasse- und Energieerträgen, zu Wasser-, Düngemittel- und Pflanzenschutzmittelbedarf sowie zu umweltrelevanten Inhaltsstoffen, Lachgasemissionen und Entzug bzw. Anreicherung von Kohlenstoff im Boden getroffen. Darüber hinaus werden die Ergebnisse aktueller Energie- und CO₂-Bilanzen vorgestellt und diskutiert. Zusammenfassend wird festgestellt, dass für Ligno-Zellulose-Nutzung vorgesehene Energiepflanzen i. allg. vorteilhafter sind als die Öl, Zucker und Stärke liefernden Pflanzen, weil von ihnen die gesamte oberirdische Pflanzenmasse genutzt werden kann, die Artenvielfalt größer und Stickstoffbedarf und Lachgasemissionen häufig geringer sind, und weil in Zusammenhang mit konventionellen und insbesondere mit künftigen Energietechnologien hohe CO₂-Minderungsraten je Hektar erreicht werden.     

Sulfated Polysaccharides from Macroalgae Are Potent Dual Inhibitors of Human ATP-Hydrolyzing Ectonucleotidases NPP1 and CD39

Extracellular ATP mediates proinflammatory and antiproliferative effects via activation of P2 nucleotide receptors. In contrast, its metabolite, the nucleoside adenosine, is strongly immunosuppressive and enhances tumor proliferation and metastasis. The conversion of ATP to adenosine is catalyzed by ectonucleotidases, which are expressed on immune cells and typically upregulated on tumor cells. In the present study, we identified sulfopolysaccharides from brown and red sea algae to act as potent dual inhibitors of the main ATP-hydrolyzing ectoenzymes, ectonucleotide pyrophosphatase/phosphodiesterase-1 (NPP1) and ecto-nucleoside triphosphate diphosphohydrolase-1 (NTPDase1, CD39), showing nano- to picomolar potency and displaying a non-competitive mechanism of inhibition. We showed that one of the sulfopolysaccharides tested as a representative example reduced adenosine formation at the surface of the human glioblastoma cell line U87 in a concentration-dependent manner. These natural products represent the most potent inhibitors of extracellular ATP hydrolysis known to date and have potential as novel therapeutics for the immunotherapy of cancer.     

Editorial

Journal of Plant Diseases and Protection -     

Acute lead poisoning in cows due to feeding of lead contaminated ash residue

In a dairy herd of 21 cows which were on pasture during the day at the end of May 2002, four eight years old cows were suddenly inappetent and showed severe diarrhoea consisting of black discolorate feces. A few days after the onset of the disease, three affected cows exhibited neurological disorders. These cows were admitted to the IInd Medical Clinic of the University for Veterinary Medicine in Vienna. Following clinical signs were observed: circulatory weakness, anorexia, atony of the rumen, diarrhoea and in accordance with acute lead poisoning typical signs of the central nervous system. One cow died and the other two animals were euthanized. Results of blood testing were anaemia, basophil spotting of erythrocytes, increase of liver enzymes and CK, hypocalcaemia, decrease of potassium and phosphate. The cerebrospinal fluid of two cows showed increased CK-, LDH- and AST-values. The lead contents of whole blood samples were between 0.486 and 0.928 mg/kg, of liver samples 13.3 to 114.4 mg/kg, of kidney samples 172.2 to 448 mg/kg and of rumen content 59 mg/kg fresh matter. At necropsy, enteritis, liver fluke disease and severe interstitial and alveolar pulmonary emphysema were found. Pathohistologically typical ischaemic necrosis of neurons predominantly at the tips of the gyri, disseminated petechial hemorrhages and moderate diffuse neovascularisation, but no acid-fast intranucleolar inclusion bodies in the renal tubules were observed. As causative agent of the acute lead poisoning a residue on combustion, taken up by the cows on the pasture, was confirmed. The ash residue was formed by combustion of three tires which contained 450 g heavy weights of 96.5% lead for wheel balance. The lead content of the ash residue was between 2.9 and 28 g/kg dry matter.     

Evaluation of vaccination strategies against infection with feline immunodeficiency virus (FIV) based on recombinant viral vectors expressing FIV Rev and OrfA

In recent years it has become clear that cell-mediated immunity is playing a role in the control of lentivirus infections. In particular, cytotoxic T lymphocyte responses have been associated with improved outcome of infection, especially those directed against the regulatory proteins like Rev and Tat, which are expressed early after infection. Therefore, there is considerable interest in lentiviral vaccine candidates that can induce these types of immune responses. In the present study, we describe the construction and characterisation of expression vectors based on recombinant Semliki Forest virus system and modified vaccinia virus Ankara for the expression of feline immunodeficiency virus (FIV) accessory proteins Rev and OrfA. These recombinant viral vectors were used to immunize cats using a prime-boost regimen and the protective efficacy of this vaccination strategy was assessed after challenge infection of immunized cats with FIV.