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91.
Jeppe Reitan Andersen Imad Zein Gerhard Wenzel Birte Darnhofer Joachim Eder Milena Ouzunova Thomas Lübberstedt 《BMC plant biology》2008,8(1):2
Background
Forage quality of maize is influenced by both the content and structure of lignins in the cell wall. Biosynthesis of monolignols, constituting the complex structure of lignins, is catalyzed by enzymes in the phenylpropanoid pathway. 相似文献92.
Gonçalves RF Chapman DA Bertolla RP Eder I Killian GJ 《Animal reproduction science》2008,108(3-4):375-383
This study was designed to investigate the effects of pre-incubating cattle spermatozoa or matured oocytes with purified osteopontin (OPN) from cattle milk on fertilization in cattle and embryonic development in vitro. There were two different experiments, semen from six mature Holstein bulls (Bos Taurus) was frozen with different concentrations of OPN (0, 1, 10, 100 μg/mL). Matured cattle oocytes were also pre-treated with OPN (0, 10, 100 μg/mL). In both experiments, pre-treated oocytes or frozen semen, was processed for in vitro fertilization and embryo development. Significantly more oocytes were fertilized when using frozen semen with 10 μg/mL OPN (bull 2 = 85 ± 4% and bull 5 = 78 ± 4%) than without OPN (bull 2 = 75 ± 4% and bull 5 = 69 ± 4%). Those bulls also had increase in cleavage and embryo development (bull 2 = 85 ± 3%, 41 ± 1.9%; bull 5 = 76 ± 2%, 37 ± 1.8%) compared with control (bull 2 = 75 ± 3%, 30 ± 2%; bull 5 = 68 ± 2%, 29 ± 2%). Incubating matured oocytes in 10 μg/mL OPN (87 ± 3%) and 100 μg/mL OPN (88 ± 3%) significantly increased fertilization than control (73 ± 3%). OPN also improve cleavage, and embryo development in treatments with 10 μg/mL OPN (82.7 ± 1.3%; 31.7 ± 1.4%) and 100 μg/mL OPN (85.8 ± 1.3%; 33.8 ± 1.5%) when compared with control (74.1 ± 1.3%; 24.2 ± 1.2%). These data suggest that both, spermatozoa from some bulls and oocytes may associate with OPN, suggesting a facilitory role on in vitro fertilization and embryo development. 相似文献
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95.
Elizabeth Olivares Eder Peña Eunice Marcano Julián Mostacero Guillermina Aguiar Malfy Benítez Elizabeth Rengifo 《Environmental and Experimental Botany》2009,65(1):132-141
The purpose of this study was to investigate the aluminum (Al) concentration in Lycopodium clavatum, Dicranopteris flexuosa, Sticherus nudus, Anemia villosa, Cyathea gibbosa, Pteridium arachnoideum, Pteris vittata, Thelypteris dentata, Blechnum occidentale, Elaphoglossum sporadolepis, Nephrolepis cordifolia and Polypodium pseudoaureum, species from 11 families with different phylogenetic position, found on soils with a high concentration of Al (up to 13 g kg?1 dry mass (DM)). When Al concentration and mineral nutrients in aerial organs were considered, pteridophytes were classified into three groups: group one included pteridophytes with Al concentrations over 1000 mg kg?1 DM in their aerial organs, a ratio between Al and essential plant nutrients such as Ca, Mg and P higher than one and a K/Al ratio between 0.68 and 2.56 mol mol?1. In group 1 was the well known Al-accumulator L. clavatum (Lycophyte) as well as the Neotropical ferns D. flexuosa, S. nudus (both basal leptosporangiate ferns), and C. gibbosa (core leptosporangiate tree fern). Group 2, ferns which accumulate Al over 1000 mg kg?1 DM in their fronds, and had an Al/Ca and Al/Mg ratio <1. Species in this group included E. sporadolepis and N. cordifolia (derived polypod ferns). Group 3, ferns classified as Al-excluders, showing Al concentration <782 mg kg?1 DM in the fronds, had Al/Ca and Al/Mg ratios <1, Al/P ratio ≤1 and a K/Al ratio between 18.10 and 80.36 mol mol?1. In group 3, were A. villosa (basal leptosporangiate fern) and the derived polypod ferns P. arachnoideum, P. vittata, T. dentata, B. occidentale and P. pseudoaureum. The translocation factor of Al from subterranean to aerial organs was up to 4 in S. nudus, and subterranean organs from E. sporadolepis showed the highest concentration of Al (12 g kg?1 DM). We coincide with early literature in that other criteria in addition to the Al concentration should be considered to define the Al accumulation, such as its relationship with macronutrients. For example, we propose the inclusion of K/Al ratio. We conclude that out of six Al-excluders five belonged to the derived polypods while two species from Polypodiales showed high Al concentrations. We reconfirm accumulation of Al in L. clavatum and C. gibbosa and discover two new Al-accumulating species in the more ancient ferns: S. nudus and D. flexuosa. 相似文献
96.
Richard M. Röhlig Joachim Eder Karl-Heinz Engel 《Metabolomics : Official journal of the Metabolomic Society》2009,5(4):459-477
A comparative metabolite profiling approach based on gas chromatography-mass spectrometry (GC/MS) was applied to investigate
the impact of genetic background, growing location and season on the chemical composition of maize grain. The metabolite profiling
protocol involved sub-fractionation of the metabolites and allowed the assessment of about 300 distinct analytes from different
chemical classes (polar to lipophilic), of which 167 could be identified. A comparison, over three consecutive growing seasons,
of the metabolite profiles of four maize cultivars which differed in their maturity classification, was carried out using
principal component analysis (PCA). This revealed a strong separation of one cultivar in the first growing season, which could
be explained by the immaturity of the kernels of this cultivar compared with others in the field trial. Further evaluations
by pair-wise comparison using Student’s t-test and analysis of variance (ANOVA) showed that the growing season was the most prominent impact factor driving variation
of the metabolite pool. An increased understanding of metabolic variation was achieved by analysis of a second sample set
comprising one cultivar grown for 3 years at four locations. The applied GC/MS-based metabolite profiling demonstrated the
natural variation in maize grain metabolite pools resulting from the interplay of environment, season, and genotype. 相似文献
97.
Renáta Schnablová Helena Synková Anna Vicánková Lenka Burketová Josef Eder Milena Cvikrová 《Plant Physiology and Biochemistry》2006,44(10):526-534
We present evidence that overproduction of endogenous cytokinins (CK) caused stress response in non-rooting Pssu-ipt transgenic tobacco (Nicotiana tabacum L.) grown in vitro. It was demonstrated by overaccumulation of phenolic compounds, synthesis of pathogenesis related proteins (PR proteins), and increase in peroxidase (POD) activities. Immunolocalization of zeatin and also PR-1b protein on leaf cryo-sections proved their accumulation in all mesophyll cells of transgenic tobacco contrary to control non-transgenic plants. Intensive blue autofluorescence of phenolic compounds induced by UV in cross-sections of leaf midrib showed enhanced contents of phenolics in transgenic tobacco compared with controls, nevertheless, no significant difference between both plant types was found in leaf total lignin content. Transgenic plantlets exhibited higher peroxidase activities of both soluble and ionically bound fractions compared with controls. HPLC analysis of phenolic acids confirmed the increase in all phenolic acids in transgenic tobacco except for salicylic acid (SA). The effect of high phenolic content on rooting of transgenic tobacco is discussed. 相似文献
98.
Klaus Becker Gerhard Schneider Matthias Eder Andreas Ranft Eberhard F. Kochs Walter Zieglg?nsberger Hans-Ulrich Dodt 《PloS one》2010,5(1)
Appropriate monitoring of the depth of anaesthesia is crucial to prevent deleterious effects of insufficient anaesthesia on surgical patients. Since cardiovascular parameters and motor response testing may fail to display awareness during surgery, attempts are made to utilise alterations in brain activity as reliable markers of the anaesthetic state. Here we present a novel, promising approach for anaesthesia monitoring, basing on recurrence quantification analysis (RQA) of EEG recordings. This nonlinear time series analysis technique separates consciousness from unconsciousness during both remifentanil/sevoflurane and remifentanil/propofol anaesthesia with an overall prediction probability of more than 85%, when applied to spontaneous one-channel EEG activity in surgical patients. 相似文献
99.
Jeronymo Dalapicolla Ronnie Alves Rodolfo Jaff Santelmo Vasconcelos Eder Soares Pires Gisele Lopes Nunes Jovani Bernardino de Souza Pereira Jos Tasso F. Guimares Mariana C. Dias Taís Nogueira Fernandes Daniela Scherer Fernando Marino Gomes dos Santos Alexandre Castilho Mirella Pupo Santos Emiliano Nicolas Caldern Rodrigo Lemes Martins Rodrigo Nunes da Fonseca Francisco de Assis Esteves Cecílio Frois Caldeira Guilherme Oliveira 《Ecology and evolution》2021,11(15):10119
The quillwort Isoëtes cangae is a critically endangered species occurring in a single lake in Serra dos Carajás, Eastern Amazon. Low genetic diversity and small effective population sizes (N e) are expected for narrow endemic species (NES). Conservation biology studies centered in a single species show some limitations, but they are still useful considering the limited time and resources available for protection of species at risk of extinction. Here, we evaluated the genetic diversity, population structure, N e, and minimum viable population (MVP) of I. cangae to provide information for effective conservation programs. Our analyses were based on 55 individuals collected from the Amendoim Lake and 35,638 neutral SNPs. Our results indicated a single panmictic population, moderate levels of genetic diversity, and N e in the order of thousands, contrasting the expected for NES. Negative FIS values were also found, suggesting that I. cangae is not under risk of inbreeding depression. Our findings imply that I. cangae contains enough genetic diversity to ensure evolutionary potential and that all individuals should be treated as one demographic unit. These results provide essential information to optimize ex situ conservation efforts and genetic diversity monitoring, which are currently applied to guide I. cangae conservation plans. 相似文献
100.
Eder Jorge de Oliveira Cláudia Fortes Ferreira Vanderlei da Silva Santos Onildo Nunes de Jesus Gilmara Alvarenga Fachardo Oliveira Maiane Suzarte da Silva 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(6):1423-1440