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Adequate copper (Cu2+) concentrations are required for plants; however, at higher concentrations it can also cause multiple toxic effects. In the
present study, lipid peroxidation, hydrogen peroxide levels as well as ascorbate peroxidase (APX: EC 1/11/1/11) and catalase
(CAT: EC 1.11.1.6) activities were determined in Lycopersicum esculentum Mill. and Cucumis sativus L. seedlings after 7-day exposure to copper sulfate. In addition, DNA damage in these two crops was assessed by measuring
micronucleus (MN) frequency and tail moments (TM) as determined by Comet assay. Inhibitory copper concentrations (EC50: 30 and 5.5 ppm for L. esculentum and C. sativus, respectively) were determined according to dose-dependent root inhibition curves, and EC50 and 2×EC50 were applied. Malondialdehyde (MDA) and H2O2 levels significantly increased in all groups studied. CAT activity increased in treatment groups of C. sativus. APX activity increased in L. esculentum seedlings due to 2×EC50 treatment. Reductions in mitotic indices (MI) represented Cu2+dependent root growth inhibition in all treatment groups studied. According to TMs and MN frequencies, copper exposure induced
significant DNA damage (p < 0.05) in all study groups, whereas the DNA damage induced was dose dependent in C. sativus roots. In conclusion, Cu2+induced oxidative damage, elevations in H2O2 levels and alterations in APX and CAT activities, as well as significant DNA damage in nuclei of both study groups. To our
knowledge, this is the first comparative and comprehensive study demonstrating the effects of copper on two different plant
species at relevant cytotoxic concentrations at both biochemical and genotoxicity levels with multiple end points. 相似文献
136.
Erol?Ba?arEmail author Murat??zg?ren Canan?Ba?ar-Ero?lu Sirel?Karaka? 《Theorie in den Biowissenschaften》2003,121(4):371-386
This paper presents superbinding, a concept that represents integrative oscillatory dynamics over the time and space axes. Principle of superposition describes integration over the temporal axis; selectively distributed and selectively coherent oscillatory neural populations describe integration over the spatial axis. Integrative activity is a function of the coherences between spatial locations of the brain; these coherences vary according to the type of sensory and or cognitive event and possibly the consciousness state of the species. Complex percepts and integrative activity in general that is achieved by superbinding supported by the neurons-brain theory may replace the Sherringtonian integrative brain function that is achieved through the single neuron doctrine.
Results of recent experiments related to the percept of the grandmother-face support our concept of super-synergy in the whole brain in order to explain manifestation of Gestalts and Memory-Stages. The strategies of the Grandmother paradigm may open new horizons in search of memories or evolving memories, and possibly provide relevant clinical applications. 相似文献
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Katarzyna Bozek Yuning Wei Zheng Yan Xiling Liu Jieyi Xiong Masahiro Sugimoto Masaru Tomita Svante P??bo Raik Pieszek Chet C. Sherwood Patrick R. Hof John J. Ely Dirk Steinhauser Lothar Willmitzer Jens Bangsbo Ola Hansson Josep Call Patrick Giavalisco Philipp Khaitovich 《PLoS biology》2014,12(5)
Metabolite concentrations reflect the physiological states of tissues and cells. However, the role of metabolic changes in species evolution is currently unknown. Here, we present a study of metabolome evolution conducted in three brain regions and two non-neural tissues from humans, chimpanzees, macaque monkeys, and mice based on over 10,000 hydrophilic compounds. While chimpanzee, macaque, and mouse metabolomes diverge following the genetic distances among species, we detect remarkable acceleration of metabolome evolution in human prefrontal cortex and skeletal muscle affecting neural and energy metabolism pathways. These metabolic changes could not be attributed to environmental conditions and were confirmed against the expression of their corresponding enzymes. We further conducted muscle strength tests in humans, chimpanzees, and macaques. The results suggest that, while humans are characterized by superior cognition, their muscular performance might be markedly inferior to that of chimpanzees and macaque monkeys. 相似文献
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Betina M. Porcel France Denoeud Fred Opperdoes Benjamin Noel Mohammed-Amine Madoui Tansy C. Hammarton Mark C. Field Corinne Da Silva Arnaud Couloux Julie Poulain Michael Katinka Kamel Jabbari Jean-Marc Aury David A. Campbell Roxana Cintron Nicholas J. Dickens Roberto Docampo Nancy R. Sturm V. Lila Koumandou Sandrine Fabre Pavel Flegontov Julius Luke? Shulamit Michaeli Jeremy C. Mottram Balázs Sz??r Dan Zilberstein Frédéric Bringaud Patrick Wincker Michel Dollet 《PLoS genetics》2014,10(2)
Members of the family Trypanosomatidae infect many organisms, including animals, plants and humans. Plant-infecting trypanosomes are grouped under the single genus Phytomonas, failing to reflect the wide biological and pathological diversity of these protists. While some Phytomonas spp. multiply in the latex of plants, or in fruit or seeds without apparent pathogenicity, others colonize the phloem sap and afflict plants of substantial economic value, including the coffee tree, coconut and oil palms. Plant trypanosomes have not been studied extensively at the genome level, a major gap in understanding and controlling pathogenesis. We describe the genome sequences of two plant trypanosomatids, one pathogenic isolate from a Guianan coconut and one non-symptomatic isolate from Euphorbia collected in France. Although these parasites have extremely distinct pathogenic impacts, very few genes are unique to either, with the vast majority of genes shared by both isolates. Significantly, both Phytomonas spp. genomes consist essentially of single copy genes for the bulk of their metabolic enzymes, whereas other trypanosomatids e.g. Leishmania and Trypanosoma possess multiple paralogous genes or families. Indeed, comparison with other trypanosomatid genomes revealed a highly streamlined genome, encoding for a minimized metabolic system while conserving the major pathways, and with retention of a full complement of endomembrane organelles, but with no evidence for functional complexity. Identification of the metabolic genes of Phytomonas provides opportunities for establishing in vitro culturing of these fastidious parasites and new tools for the control of agricultural plant disease. 相似文献
140.
Aneta Ksi??ek Karol Zub Paulina A. Szafrańska Monika Wieczorek Marek Konarzewski 《Biology letters》2014,10(12)
Despite its presumed significance, the association between immune defence, energy expenditures and overwinter survival is rarely studied. We analysed individual variation in immunocompetence quantified as neutrophil-to-lymphocyte ratio (N/L), total white blood cells (WBC) and natural antibody levels, along with resting (RMR) and peak metabolic rates (PMR) and mortality during three consecutive winter seasons in a natural population of the root vole, Microtus oeconomus. In early winter, WBC count was negatively correlated with RMR, whereas N/L ratio was negatively correlated with swim-elicited PMR. We suggest that while the first correlation reflected the trade-off between energy allocation in immunocompetence and other metabolically demanding processes, the latter correlation stemmed from stress-induced immunosuppression elicited by the necessity to cope with swimming in frequently flooded habitat. In addition, the analysis carried out during the first year of study characterized by a high population density and prevalence of infestation with a blood parasite—Babesia spp., showed that its intensity was inversely correlated with the N/L ratio. In summary, our results suggest that elevated N/L ratio increases the winter survival of free-ranging rodents by increasing their ability to cope with parasitic infections. 相似文献