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Konstantin Z. Budin† 《Genetic Resources and Crop Evolution》2002,49(3):229-235
The present paper provides a review of data from literature sources and results of research carried out at the Institute of PlantIndustry with the aim of identifying genetic centres of formation of late blight resistant genotypes. For the research results, speciesfrom the potato collection of VIR were used. 相似文献
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Rainer Gryschko Rainer Kuhnle Konstantin Terytze Jörn Breuer Karl Stahr 《Journal of Soils and Sediments》2005,5(2):101-106
Background, Aims and Scope The German DIN 19730 (1997) describes a method for the extraction of readily available trace elements from soil by shaking the soil with 1 M NH4NO3-solution. Based on this method trigger and action values for the transfer of heavy metals and arsenic from soils to plants have been published in the German Federal Soil Protection and Contaminated Sites Ordinance (BBodSchV 1999). The chemical mechanisms involved in this soil extraction procedure were evaluated in some detail to create requirements to improve environmental risk assessment for soil contaminations.Methods The chemical mechanisms involved when soil is extracted with 1 M NH4NO3-solution were evaluated. This was followed by a laboratory experiment to quantify the formation of soluble metal ammine complexes during the extraction.
Cd, Zn, Ni, Cu, Co and Hg were extracted from 16 soils by 1 M NH4NO3, 1 M KNO3 and water. pH was adjusted in 5 steps between 5.0 to 7.5. The potassium cation (K+) and the ammonium cation (NH4+) behave similarly when cations from soil surfaces are desorbed, because they have almost identical ion radii (e.g. 0.133 and 0.143 nm). K+ does not form ammine complexes with other ions, whereas, due to the increasing formation of NH3 from NH4 by dissociation with rising pH, metal ammine complex formation is an important process in soil extraction when using ammonium salt solutions. A difference in the extraction efficiency of 1 M NH4NO3- and 1 M KNO3-solution for a given soil can therefore be attributed to the formation of soluble metal ammine complexes. Conclusion Our experiments resulted in considerably higher extraction rates of Cu, Cd and Hg by 1 M NH4NO3-solution as compared to 1 M KNO3-solution. This effect, caused by the formation of soluble metal ammine complexes, was only evident in soils with higher readily soluble heavy metal contents and a soil pH above 6 – 6.5 for Cu and 7 – 7.5 for Cd. Further chemical mechanisms involved when soils are extracted with 1 M NH4NO3 are a moderate decrease in pH and an increase in ionic strength. Most of the colloids and parts of soluble metal-organic complexes are precipitated due to the high ionic strength. High ionic strength also decreases the activity of metal-OH+ species and the electrostatic potential of the particle surfaces, which in turn, increases the desorption of heavy metal cations from negatively charged soil surfaces. In contrast, the adsorption of anions like arsenate is favoured by the decreasing electrostatic potential.
The prediction of heavy metal uptake by plants from the results of the 1 M NH4NO3-solution extraction fits well for elements, which are mainly bound by low strength electrostatic forces to the soils. Such conditions are found in acidic soils for Cd and Tl, which have a low tendency for hydrolysis compared to other heavy metals. The correlation between 1 M NH4NO3 soil extraction and plant uptake is less significant for Ni and Zn. Only low positive correlation coefficients have been found for Pb, As, Hg and for the Cu-uptake by wheat. Imprecise prediction of plant uptake of heavy metals by the extraction with 1 M NH4NO3-solution is mainly caused by conditions leading to an overestimation of plant availability such as elements are strongly bound to soils, or low soluble trace element contents in soils. Neutral to alkaline soil pH can also lead to imprecise prediction due to increasing formation of soluble metal-organic (Cu, Pb, Hg) and metal ammine (Hg, Cu, Cd) complexes and less importantly due to the formation of colloids. Therefore, at low 1 M NH4NO3-extractable soil contents usually no high plant contents are to be expected. Recommendation and Outlook Extraction of soil with 1 M NH4NO3-solution is a suitable method for the determination of readily soluble and plant available trace element contents. The chemical soil extraction process may cause misleading predictions of the transfer of trace elements to plants for some soil properties. This knowledge should be used to improve risk assessment of soil contaminations. It has to be considered, that the processes involved in plant uptake of trace elements are too complex to expect that just one soil extraction method can always guarantee a correct prognosis of toxicological significant element contents in plants. Soil analyses may be used for the preliminary examination of suspicious areas and the demarcation of contaminated areas. The results of soil analyses should be checked additionally by plant analyses especially under conditions with a high probability for misleading results by the 1 M NH4NO3-extraction. Alternatively, extraction with 1 M KNO3-solution can be performed to exclude the effect of metal ammine complex formation. 相似文献
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Miller M Terrell S Lyashchenko K Greenwald R Harris B Thomsen BV Fontenot D Stetter M Neiffer D Fleming G 《Journal of zoo and wildlife medicine》2011,42(3):468-472
Two adult female bontebok (Damaliscus pygarus dorcas) were euthanized because of signs of pneumonia and weakness (case 1), and a nonresponsive lameness with draining fistula (case 2). Necropsy findings were similar in both cases and consisted of disseminated granulomatous lesions in the liver, kidneys, spleen, lungs, pleural surfaces, and multiple lymph nodes. Mycobacterium kansasii was isolated from both cases after multiple attempts on a variety of samples by two laboratories. The remaining four animals in the herd were tested for antibody responses using the Chembio ElephantTB STAT-PAK, DPP VetTB kits, and multi-antigen print immunoassay (MAPIA), for immune reaction using the intradermal tuberculin test, and by tracheal wash cultures, and thoracic radiographs. Banked serum samples collected in 2005 and obtained from the original institution, revealed 1/9 (11.11%) seropositive animals using the three immunoassays. Retesting the current herd in 2008 showed 2/6 (33.33%) seropositive animals by the three tests, with MAPIA demonstrating antibody reactivity to MPB83 and MPB70 proteins. Inconsistent intradermal tuberculin test results, cross-reactivity in serologic assays designed for tuberculosis detection, difficulty in obtaining definitive identification by culture, and inability to identify a source of infection created challenges in distinguishing the atypical mycobacteriosis due to M. kansasii from the initially suspected tuberculous infection in this herd. Owing to regulatory considerations, differences in host-to-host transmission, and source of infection between Mycobacterium tuberculosis complex and nontuberculous mycobacteria, correct diagnosis is crucial for management of these diseases in wildlife species. 相似文献
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Natalya V. Ageenko Konstantin V. Kiselev Pavel S. Dmitrenok Nelly A. Odintsova 《Marine drugs》2014,12(7):3874-3891
The quinone pigments of sea urchins, specifically echinochrome and spinochromes, are known for their effective antioxidant, antibacterial, antifungal, and antitumor activities. We developed in vitro technology for inducing pigment differentiation in cell culture. The intensification of the pigment differentiation was accompanied by a simultaneous decrease in cell proliferation. The number of pigment cells was two-fold higher in the cells cultivated in the coelomic fluids of injured sea urchins than in those intact. The possible roles of the specific components of the coelomic fluids in the pigment differentiation process and the quantitative measurement of the production of naphthoquinone pigments during cultivation were examined by MALDI and electrospray ionization mass spectrometry. Echinochrome A and spinochrome E were produced by the cultivated cells of the sand dollar Scaphechinus mirabilis in all tested media, while only spinochromes were found in the cultivated cells of another sea urchin, Strongylocentrotus intermedius. The expression of genes associated with the induction of pigment differentiation was increased in cells cultivated in the presence of shikimic acid, a precursor of naphthoquinone pigments. Our results should contribute to the development of new techniques in marine biotechnology, including the generation of cell cultures producing complex bioactive compounds with therapeutic potential. 相似文献
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Konstantin Chekanov Elena Lobakova Irina Selyakh Larisa Semenova Roman Sidorov Alexei Solovchenko 《Marine drugs》2014,12(8):4504-4520
We report on a novel arctic strain BM1 of a carotenogenic chlorophyte from a coastal habitat with harsh environmental conditions (wide variations in solar irradiance, temperature, salinity and nutrient availability) identified as Haematococcus pluvialis Flotow. Increased (25‰) salinity exerted no adverse effect on the growth of the green BM1 cells. Under stressful conditions (high light, nitrogen and phosphorus deprivation), green vegetative cells of H. pluvialis BM1 grown in BG11 medium formed non-motile palmelloid cells and, eventually, hematocysts capable of a massive accumulation of the keto-carotenoid astaxanthin with a high nutraceutical and therapeutic potential. Routinely, astaxanthin was accumulated at the level of 4% of the cell dry weight (DW), reaching, under prolonged stress, 5.5% DW. Astaxanthin was predominantly accumulated in the form of mono- and diesters of fatty acids from C16 and C18 families. The palmelloids and hematocysts were characterized by the formation of red-colored cytoplasmic lipid droplets, increasingly large in size and number. The lipid droplets tended to merge and occupied almost the entire volume of the cell at the advanced stages of stress-induced carotenogenesis. The potential application of the new strain for the production of astaxanthin is discussed in comparison with the H. pluvialis strains currently employed in microalgal biotechnology. 相似文献
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Nikita Yu. Zarubin Elena N. Kharenko Olga V. Bredikhina Leonid O. Arkhipov Konstantin V. Zolotarev Anton N. Mikhailov Valeriya I. Nakhod Marina V. Mikhailova 《Marine drugs》2021,19(8)
Waste from fish cutting (heads, swim bladders, fins, skin, and bones) is a high-value technological raw material for obtaining substances and products with a wide range of properties. The possibility of using waste from cutting fish of the Gadidae family: the Alaska pollock (Gadus chalcogrammus) and the Pacific cod (Gadus macrocephalus), processed in the coastal zone, is scientifically substantiated. In this work, a technology has been developed for processing accumulated waste from fish cutting in order to obtain fish gelatin, which is characterized by high protein content (more than 80.0%) and a full set of essential and nonessential amino acids. We studied the quality of fish gelatin obtained from wastes from cutting the fish of the Gadidae family. The possibility of using fish gelatin as a component of fish products is shown; the dose of its introduction into the fish products is substantiated. The data obtained made it possible to recommend the use of fish processing waste products as a gelling component and a source of amino acids in multicomponent food systems. 相似文献
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Perumal Azhaguvel Dolores Mornhinweg Dhanasekaran Vidya‐Saraswathi Jackie C. Rudd Konstantin Chekhovskiy Malay Saha Timothy J. Close Lynn S. Dahleen Yiqun Weng 《Plant Breeding》2014,133(2):227-233
The greenbug, Schizaphis graminum (Rondani) is an extremely damaging aphid pest of barley (Hordeum vulgare L.) particularly in the southern Great Plains of the USA. The simply inherited, dominant resistance gene Rsg1 is in all greenbug‐resistant US barley cultivars. In this study, we conducted molecular mapping of Rsg1 using an F2:3 population derived from a cross between the greenbug‐resistant Post 90*4/R015 and susceptible CI2260 inbred lines. Segregation of host responses to greenbug biotype E infestation confirmed that a single dominant gene is responsible for greenbug resistance in Post 90*4/R015. Simple sequence repeat (SSR) markers evenly distributed along the seven barley chromosomes were employed for the construction of a framework genetic map. Linkage analysis placed the Rsg1 locus in the long arm of chromosome 3H (3HL) flanked by SSR markers Bmag0877 and GBM1420 that were 35 cM apart. Polymorphic single‐nucleotide polymorphism (SNP) markers in 3HL were identified from an Illumina GoldenGate SNP assay and used for targeted mapping to locate Rsg1 to an 8.4‐cM interval. Comparative analysis identified syntenic genomic regions in Brachypodium distachyon chromosome 2, in which 37 putative genes were annotated including a NB‐LRR‐type resistance gene homologue that may be a potential candidate gene for the Rsg1 locus of barley. Results from this study offer a starting point for fine mapping and cloning of this aphid resistance gene in barley. 相似文献
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Sergey A. Dyshlovoy Moritz Kaune Jessica Hauschild Malte Kriegs Konstantin Hoffer Tobias Busenbender Polina A. Smirnova Maxim E. Zhidkov Ekaterina V. Poverennaya Su Jung Oh-Hohenhorst Pavel V. Spirin Vladimir S. Prassolov Derya Tilki Carsten Bokemeyer Markus Graefen Gunhild von Amsberg 《Marine drugs》2020,18(12)
Efficacy and mechanism of action of marine alkaloid 3,10-dibromofascaplysin (DBF) were investigated in human prostate cancer (PCa) cells harboring different levels of drug resistance. Anticancer activity was observed across all cell lines examined without signs of cross-resistance to androgen receptor targeting agents (ARTA) or taxane based chemotherapy. Kinome analysis followed by functional investigation identified JNK1/2 to be one of the molecular targets of DBF in 22Rv1 cells. In contrast, no activation of p38 and ERK1/2 MAPKs was observed. Inhibition of the drug-induced JNK1/2 activation or of the basal p38 activity resulted in increased cytotoxicity of DBF, whereas an active ERK1/2 was identified to be important for anticancer activity of the alkaloid. Synergistic effects of DBF were observed in combination with PARP-inhibitor olaparib most likely due to the induction of ROS production by the marine alkaloid. In addition, DBF intensified effects of platinum-based drugs cisplatin and carboplatin, and taxane derivatives docetaxel and cabazitaxel. Finally, DBF inhibited AR-signaling and resensitized AR-V7-positive 22Rv1 prostate cancer cells to enzalutamide, presumably due to AR-V7 down-regulation. These findings propose DBF to be a promising novel drug candidate for the treatment of human PCa regardless of resistance to standard therapy. 相似文献