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551.
552.
Natalia N. Nalivaeva Lilia Fisk Rosa M. Canet. Aviles Svetlana A. Plesneva Igor A. Zhuravin Anthony J. Turner 《International journal of peptide research and therapeutics》2003,10(5-6):455-462
Summary In the present study we have investigated the effect of prenatal hypoxia on expression of amyloid precursor protein (APP)
and some metallopeptidases, which regulate β-amyloid peptide (Aβ) levels (neprilysin (NEP) and endothelin-converting enzyme
(ECE-1)) in the cortex of rats during different periods of postnatal development. We have found that the level of APP in the
sensorimotor cortex (SMC) of rats, analysed by Western blotting, increases from days 1 to 5 of postnatal development and then
steadily decreases with age, with the most dramatic decline in the period from day 180 to 600. In the cortex of rats subjected
to prenatal hypoxia on day 13.5 of embryogenesis, the postnatal levels of APP were higher than in the control. Secretion of
the soluble form of APP (sAPP) by α-secretase was found to be the most active on day 30 of postnatal development and there
was a significant decrease in the production of sAPP after prenatal hypoxia. NEP was found to be expressed in the cortex of
rats only at the early stages of postnatal development and it was barely detectable in adult rats. The decline of NEP levels
during ageing might contribute to accumulation of Aβ in later life in humans. Prenatal hypoxia resulted in a significant decrease
of NEP expression on day 10, but its level was recovered when animals were preconditioned to mild hypoxia. A similar phenomenon
was observed when the expression of ECE-1 was analysed. Overall, prenatal hypoxia leads to significant changes in the levels
of APP and expression of metallopeptidases involved in amyloid metabolism during all postnatal life and preconditioning to
hypoxia appeared to be neuroprotective. 相似文献
553.
554.
Ana Lilia Alzate-Marin Ivan Schuster Maurilio Alves Moreira Everaldo Gonçalves de Barros 《Journal of Phytopathology》2009,157(1):70-72
Different genes might be involved in Colletotrichum lindemuthianum resistance in leaves and stem of common bean. This work aimed to study the genetic mechanisms of the resistance in the leaf and stem in segregating populations from backcrosses involving resistant cultivar AN 910408 and susceptible cultivar Rudá inoculated with spore suspensions of C. lindemuthianum race 83. Our results indicate that two genes which interact epistatically, one dominant and one recessive, are involved in the genetic control of leaf anthracnose resistance. As for stem anthracnose resistance, two genes also epistatic, one dominant and one recessive, explain the resistance to C. lindemuthianum race 83. The recessive gene is the same for leaf and stem resistance; however, the dominant genes are distinct and independent from each other. The three independent resistance genes of AN 910408 observed in this work could be derived from Guanajuato 31. 相似文献