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801.
E. Kádár G. Huguet L. Aldavert‐Vera I. Morgado‐Bernal P. Segura‐Torres 《Genes, Brain & Behavior》2013,12(8):771-779
Post‐training lateral hypothalamus (LH) intracranial self stimulation (ICSS) has a reliable enhancing effect on explicit memory formation evaluated in hippocampus‐dependent tasks such as the Morris water maze. In this study, the effects of ICSS on gene expression in the hippocampus are examined 4.5 h post treatment by using oligonucleotide microarray and real‐time PCR, and by measuring Arc protein levels in the different layers of hippocampal subfields through immunofluorescence. The microarray data analysis resulted in 65 significantly regulated genes in rat ICSS hippocampi compared to sham, including cAMP‐mediated signaling as one of the most significantly enriched Database for Annotation, Visualization and Integrated Discovery (DAVID) functional categories. In particular, expression of CREB‐dependent synaptic plasticity related genes (c‐Fos, Arc, Bdnf, Ptgs‐2 and Crem and Icer) was regulated in a time‐dependent manner following treatment administration. Immunofluorescence results showed that ICSS treatment induced a significant increase in Arc protein expression in CA1 and DG hippocampal subfields. This empirical evidence supports our hypothesis that the effect of ICSS on improved or restored memory functions might be mediated by increased hippocampal expression of activity‐dependent synaptic plasticity related genes, including Arc protein expression, as neural mechanisms related to memory consolidation . 相似文献
802.
Production of sustainable aviation fuels (SAFs) using microbes still requires huge research efforts to fulfill the needs of aviation, both in the biological utilization of raw materials as well as in the biological processes to convert these materials (oils, sugars, aromatic compounds and others) into SAFs. However, we should also be aware of the microbiology constraints that, in some cases, will not allow us to reach the commercial level and that, by creating false expectations we will harm the credibility of microbiologists. However, in our opinion microbiologists can and should continue to find new avenues for producing SAFs, and for evaluating the advantages and feasibility of their production. This last step will require a close collaboration between researchers and industry. 相似文献
803.
804.
Herminia I. Perez Hector Luna Luis A. Maldonado Horacio Sandoval Norberto Manjarrez Aida Solis Remedios Sanchez 《Biotechnology letters》1998,20(1):77-79
Whole cells of Nocardia corallina B-276, oxidized 21 substituted benzyl alcohols, at 1 mM scale, to carboxylic acids at 28-30°C, giving yields of products from 5 to 77%. 相似文献
805.
Structural and physiological changes in the roots of tomato plants over-expressing a basic peroxidase 总被引:4,自引:0,他引:4
Miguel A. Lucena Remedios Romero-Aranda Jose A. Mercado Jesús Cuartero Victoriano Valpuesta Miguel A. Quesada 《Physiologia plantarum》2003,118(3):422-429
Previous studies on the tomato ( Lycopersicon esculentum Mill.) peroxidase TPX1, including the development of transgenic tomato over-expressing this gene, supported an involvement of this peroxidase in the synthesis of lignin and suberin. The transgenic plants showed a wilty phenotype at flowering, but the relationship between this role in ligno-suberization and this phenotype was not clear. In the present study a histological approach and the measurement of water-related parameters have been performed in order to obtain an insight into the origin of this phenotype. Clear differences between transgenic and non-transgenic roots were observed in the cross-sections of the basal root zones where secondary growth was evident. The diameter of the xylem vessel was diminished in the transgenic plants. Total area corresponding to xylem in the basal cross-sections decreased 3.9 fold in the transgenic roots. In addition, the radial and outer tangential walls of the exodermis cells were more ligno-suberized in transgenic than in non-transgenic plants. After fruit set, predawn and midday water potentials were lower in transgenic than in-non-transgenic plants. At midday, the stomatal conductance was also lower in the transgenic plants, 494±69 versus 594±60 mmol m−2 s−1 . Root hydraulic conductances of the transgenic and non-transgenic plants were 1.4±0.38 and 3.47±0.19 g water min−1 MPa−1 , respectively. The results obtained support that the phenotype is caused by the anatomical differences found in the transgenic roots. These differences would be the cause of a increased resistance to water flow in the roots that would negatively affect the water supply to the shoot and, as a consequence, resulted in a decreased water potential in the leaves. 相似文献
806.