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921.
Fabricio Ballarini María Cecilia Martínez Magdalena Díaz Perez Diego Moncada Haydée Viola 《PloS one》2013,8(6)
Education is the most traditional means with formative effect on the human mind, learning and memory being its fundamental support. For this reason, it is essential to find different strategies to improve the studentś performance. Based on previous work, we hypothesized that a novel experience could exert an enhancing effect on learning and memory within the school environment. Here we show that novel experience improved the memory of literary or graphical activities when it is close to these learning sessions. We found memory improvements in groups of students who had experienced a novel science lesson 1 hour before or after the reading of a story, but not when these events were 4 hours apart. Such promoting effect on long-term memory (LTM) was also reproduced with another type of novelty (a music lesson) and also after another type of learning task (a visual memory). Interestingly, when the lesson was familiar, it failed to enhance the memory of the other task. Our results show that educationally relevant novel events experienced during normal school hours can improve LTM for tasks/activities learned during regular school lessons. This effect is restricted to a critical time window around learning and is particularly dependent on the novel nature of the associated experience. These findings provide a tool that could be easily transferred to the classroom by the incorporation of educationally novel events in the school schedule as an extrinsic adjuvant of other information acquired some time before or after it. This approach could be a helpful tool for the consolidation of certain types of topics that generally demand a great effort from the children. 相似文献
922.
Magdalena Füßl Ann-Christine Knig Jürgen Eirich Markus Hartl Laura Kleinknecht Alexandra-Viola Bohne Anne Harzen Katharina Kramer Dario Leister Jrg Nickelsen Iris Finkemeier 《The Plant journal : for cell and molecular biology》2022,109(1):261-277
The green alga Chlamydomonas reinhardtii is one of the most studied microorganisms in photosynthesis research and for biofuel production. A detailed understanding of the dynamic regulation of its carbon metabolism is therefore crucial for metabolic engineering. Post-translational modifications can act as molecular switches for the control of protein function. Acetylation of the ?-amino group of lysine residues is a dynamic modification on proteins across organisms from all kingdoms. Here, we performed mass spectrometry-based profiling of proteome and lysine acetylome dynamics in Chlamydomonas under varying growth conditions. Chlamydomonas liquid cultures were transferred from mixotrophic (light and acetate as carbon source) to heterotrophic (dark and acetate) or photoautotrophic (light only) growth conditions for 30 h before harvest. In total, 5863 protein groups and 1376 lysine acetylation sites were identified with a false discovery rate of <1%. As a major result of this study, our data show that dynamic changes in the abundance of lysine acetylation on various enzymes involved in photosynthesis, fatty acid metabolism, and the glyoxylate cycle are dependent on acetate and light. Exemplary determination of acetylation site stoichiometries revealed particularly high occupancy levels on K175 of the large subunit of RuBisCO and K99 and K340 of peroxisomal citrate synthase under heterotrophic conditions. The lysine acetylation stoichiometries correlated with increased activities of cellular citrate synthase and the known inactivation of the Calvin–Benson cycle under heterotrophic conditions. In conclusion, the newly identified dynamic lysine acetylation sites may be of great value for genetic engineering of metabolic pathways in Chlamydomonas. 相似文献
923.
Palacios GC Gonzalez MN Beltran M Arredondo JL Torres J Solorzano F 《Current microbiology》2007,54(1):42-47
Highly virulent clonotypes of serotype III seem to cause much of the perinatal morbidity and mortality attributed to Streptococcus agalactiae (group B streptococci, GBS), One of these clonal types, designated the “high-virulence clone” (HVC), was identified by its
inability to grow at 40°C in a chemically defined medium. In the present study, this inability to grow at high temperatures
was used as a marker to identify HVC in a sample of 286 Mexican GBS isolates. Forty-three isolates (15%) were identified as
belonging to this clone: 15 were invasive isolates, 33 were serotype III (77%), and 10 were of serotypes other than type III
(23%). These results demonstrate that HVC is more prevalent in Mexico than previously reported and that this clone is not
restricted to serotype III isolates. 相似文献
924.
Astrocyte-like cells, which act as stem cells in the adult brain, reside in a few restricted stem cell niches. However, following brain injury, glia outside these niches acquire or reactivate stem cell potential as part of reactive gliosis. Recent studies have begun to uncover the molecular pathways involved in this process. A comparison of molecular pathways activated after injury with those involved in the normal neural stem cell niches highlights strategies that could overcome the inhibition of neurogenesis outside the stem cell niche and instruct parenchymal glia towards a neurogenic fate. This new view on reactive glia therefore suggests a widespread endogenous source of cells with stem cell potential, which might potentially be harnessed for local repair strategies. 相似文献
925.
Magdalena Bohutínsk Mark Alston Patrick Monnahan Terezie Mandkov Sian Bray Pirita Paajanen Filip Kol Levi Yant 《Molecular biology and evolution》2021,38(9):3910
Whole genome duplication (WGD) can promote adaptation but is disruptive to conserved processes, especially meiosis. Studies in Arabidopsis arenosa revealed a coordinated evolutionary response to WGD involving interacting proteins controlling meiotic crossovers, which are minimized in an autotetraploid (within-species polyploid) to avoid missegregation. Here, we test whether this surprising flexibility of a conserved essential process, meiosis, is recapitulated in an independent WGD system, Cardamine amara, 17 My diverged from A. arenosa. We assess meiotic stability and perform population-based scans for positive selection, contrasting the genomic response to WGD in C. amara with that of A. arenosa. We found in C. amara the strongest selection signals at genes with predicted functions thought important to adaptation to WGD: meiosis, chromosome remodeling, cell cycle, and ion transport. However, genomic responses to WGD in the two species differ: minimal ortholog-level convergence emerged, with none of the meiosis genes found in A. arenosa exhibiting strong signal in C. amara. This is consistent with our observations of lower meiotic stability and occasional clonal spreading in diploid C. amara, suggesting that nascent C. amara autotetraploid lineages were preadapted by their diploid lifestyle to survive while enduring reduced meiotic fidelity. However, in contrast to a lack of ortholog convergence, we see process-level and network convergence in DNA management, chromosome organization, stress signaling, and ion homeostasis processes. This gives the first insight into the salient adaptations required to meet the challenges of a WGD state and shows that autopolyploids can utilize multiple evolutionary trajectories to adapt to WGD. 相似文献
926.
927.
928.
Dziegiel P Dolilńska-Krajewska B Dumańska M Wecławek J Jeleń M Podhorska-Okołów M Jagoda E Fic M Zabel M 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2007,45(1):21-25
Langerhans cell histiocytoses (LCH) represent rare diseases of unclear etiology and pathogenesis. Most of the cases include children, 1 to 15 years of age, and various organs are involved (bones, skin, liver, lymph nodes, bone marrow and other). The diagnosis of LCH used to be established by biopsy of the inflamed tissue and demonstration of expression of markers specific for Langerhans cells: CD1a and langerin. The diagnosis can be ultimately confirmed by demonstration of Birbeck's granules in the electron microscopy. The present study was aimed at immunocytochemical demonstration, in the examined LCH material (skin, bones, lymph nodes), of the specific antigen expression and at comparing it with the presence of Birbeck's granules. In the examined 11 cases co-expression of CD1a with langerin and with the presence of Birbeck's granules was noted. Also in all examined biopsies the expression of S-100 protein on inflammatory cells was found. The results corroborate the usefulness of immunocytochemical studies on CD 1 a and langerin expression in diagnosis of LCH. 相似文献
929.
Wojtczak L Lebiedzińska M Suski JM Więckowski MR Schönfeld P 《Biochemical and biophysical research communications》2011,(4):772-776
Release of reactive oxygen species (ROS), measured as the sum of hydrogen peroxide (H2O2) and superoxide anion radical (), from respiring rat heart and skeletal muscle mitochondria was significantly decreased by millimolar concentrations of GTP or GDP. Attempts to differentiate between the two forms of ROS showed that the release of rather than that of H2O2 was affected. Meanwhile, intramitochondrial ROS accumulation, measured by inactivation of aconitase, increased. These results suggest that guanine nucleotides inhibit the release of from mitochondria. As these nucleotides are known inhibitors of uncoupling proteins (UCPs), it is proposed that UCPs may function as carriers of , thus enabling its removal from the matrix compartment. 相似文献
930.
Andrew J. Zimolzak Claire M. Spettell Joaquim Fernandes Vincent A. Fusaro Nathan P. Palmer Suchi Saria Isaac S. Kohane Magdalena A. Jonikas Kenneth D. Mandl 《PloS one》2013,8(11)