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61.
Acanthamoeba castellanii promotion of in vitro survival and transmission of coxsackie b3 viruses 下载免费PDF全文
This work was undertaken to determine whether Acanthamoeba could play a role in the survival and transmission of coxsackieviruses and focused on in vitro interactions between Acanthamoeba castellanii and coxsackie B3 viruses (CVB-3). Residual virus titer evaluations and immunofluorescence experiments revealed a remarkable CVB-3 adsorption on amoeba surfaces and accumulation inside cells. The survival of viruses was independent of the dynamics of amoeba replication and encystment. In addition, our results indicated that virus-infected amoebas can release infectious viruses during interaction with human macrophages. On the basis of these data, Acanthamoeba appears to be a potential promoter of the survival of coxsackieviruses and their transmission to human hosts. 相似文献
62.
Jorge Curiel Yuste Josep Barba Antonio José Fernandez‐Gonzalez Manuel Fernandez‐Lopez Stefania Mattana Jordi Martinez‐Vilalta Pau Nolis Francisco Lloret 《Ecology and evolution》2012,2(12):3016-3031
The aim of this study was to understand how drought‐induced tree mortality and subsequent secondary succession would affect soil bacterial taxonomic composition as well as soil organic matter (SOM) quantity and quality in a mixed Mediterranean forest where the Scots pine (Pinus sylvestris) population, affected by climatic drought‐induced die‐off, is being replaced by Holm‐oaks (HO; Quercus ilex). We apply a high throughput DNA pyrosequencing technique and 13C solid‐state Nuclear Magnetic Resonance (CP‐MAS 13C NMR) to soils within areas of influence (defined as an surface with 2‐m radius around the trunk) of different trees: healthy and affected (defoliated) pines, pines that died a decade ago and healthy HOs. Soil respiration was also measured in the same spots during a spring campaign using a static close‐chamber method (soda lime). A decade after death, and before aerial colonization by the more competitive HOs have even taken place, we could not find changes in soil C pools (quantity and/or quality) associated with tree mortality and secondary succession. Unlike C pools, bacterial diversity and community structure were strongly determined by tree mortality. Convergence between the most abundant taxa of soil bacterial communities under dead pines and colonizer trees (HOs) further suggests that physical gap colonization was occurring below‐ground before above‐ground colonization was taken place. Significantly higher soil respiration rates under dead trees, together with higher bacterial diversity and anomalously high representation of bacteria commonly associated with copiotrophic environments (r‐strategic bacteria) further gives indications of how drought‐induced tree mortality and secondary succession were influencing the structure of microbial communities and the metabolic activity of soils. 相似文献
63.
Overexpression of the rice Osmyb4 gene increases chilling and freezing tolerance of Arabidopsis thaliana plants 总被引:11,自引:0,他引:11
Vannini C Locatelli F Bracale M Magnani E Marsoni M Osnato M Mattana M Baldoni E Coraggio I 《The Plant journal : for cell and molecular biology》2004,37(1):115-127
The expression of the gene Osmyb4, detected at low level in rice (Oryza sativa) coleoptiles grown for 3 days at 29 degrees C, is strongly induced by treatments at 4 degrees C. At sublethal temperatures of 10 and 15 degrees C, its expression in rice seedlings is already evident, but this effect cannot be vicariated by other stresses or ABA treatment. We demonstrate by transient expression that Myb4 transactivates the PAL2, ScD9 SAD and COR15a cold-inducible promoters. The Osmyb4 function in vivo is demonstrated overexpressing its cDNA in Arabidopsis thaliana plants (ecotype Wassilewskija) under the control of the constitutive CaMV 35S promoter. Myb4 overexpressing plants show a significant increased cold and freezing tolerance, measured as membrane or Photosystem II (PSII) stability and as whole plant tolerance. Finally, in Osmyb4 transgenic plants, the expression of genes participating in different cold-induced pathways is affected, suggesting that Myb4 represents a master switch in cold tolerance. 相似文献
64.
Reggiani Remo; Mattana Monica; Aurisano Nicoletta; Bertani Alcide 《Plant & cell physiology》1993,34(2):379-383
The presence of nitrate in the seed and its utilization duringanaerobic germination of rice (Oryza sativa L.) were studied.The results indicate that nitrate was reduced and assimilatedby the coleoptile for 11 days during anaerobic growth aftergermination. The importance of the anoxic utilization of nitrateis discussed. (Received June 19, 1992; Accepted January 4, 1993) 相似文献
65.
Summary Incorporation of15NO3- into amino acids was studied in 3-day-old aerobic rice seedlings (with coleoptile and root) subjected for 24h to anaerobic conditions. The incorporation of15N into glutamate, glutamine and alanine accounted for 89% and 84% of total incorporation in coleoptile and root, respectively. These findings indicate that, after the primary incorporation of15N into glutamate and glutamine, the main fate of nitrate nitrogen in rice seedlings subjected to anoxia is alanine. 相似文献
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67.
Ferredoxin-dependent glutamate synthase (Fd-Gogat; EC 1.4.7.1) in leaf and root plastids is the last enzyme involved in the
pathway of nitrate assimilation in higher plants. Arabidopsis thaliana expresses two different genes: the first, light regulated, specific of green tissues and the second expressed in other tissues.
In this work, we investigated whether in our clone, OsGog2 AC Y12595, this gene is up-regulated by light or it is expressed
under darkness. Fd-Gogat specific activity, protein and mRNA increased after light treatment in rice shoots. In roots, the
activity and the protein content remained constant, whereas the mRNA is repressed by light treatment. The results obtained
using a specific probe, situated in the 3′ untranslated region of the OsGog2 cDNA, indicated that OsGog2 gene is up-regulated by light and that its expression is tissue specific and suggested that a dark expressed Fd-Gogat gene
could be present in rice similarly as in Arabidopsis. 相似文献