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51.
52.
Alessandro Messeri Marco Morabito Gianni Messeri Giada Brandani Martina Petralli Francesca Natali Daniele Grifoni Alfonso Crisci Gianfranco Gensini Simone Orlandini 《PloS one》2015,10(12)
The frequency of natural hazards has been increasing in the last decades in Europe and specifically in Mediterranean regions due to climate change. For example heavy precipitation events can lead to disasters through the interaction with exposed and vulnerable people and natural systems. It is therefore necessary a prevention planning to preserve human health and to reduce economic losses. Prevention should mainly be carried out with more adequate land management, also supported by the development of an appropriate risk prediction tool based on weather forecasts. The main aim of this study is to investigate the relationship between weather types (WTs) and the frequency of floods and landslides that have caused damage to properties, personal injuries, or deaths in the Italian regions over recent decades. In particular, a specific risk index (WT-FLARI) for each WT was developed at national and regional scale. This study has identified a specific risk index associated with each weather type, calibrated for each Italian region and applicable to both annual and seasonal levels. The risk index represents the seasonal and annual vulnerability of each Italian region and indicates that additional preventive actions are necessary for some regions. The results of this study represent a good starting point towards the development of a tool to support policy-makers, local authorities and health agencies in planning actions, mainly in the medium to long term, aimed at the weather damage reduction that represents an important issue of the World Meteorological Organization mission. 相似文献
53.
Mohammadi M Chalavi V Novakova-Sura M Laliberté JF Sylvestre M 《Biotechnology and bioengineering》2007,97(3):496-505
Optimized plant-microbe bioremediation processes in which the plant initiates the metabolism of xenobiotics and releases the metabolites in the rhizosphere to be further degraded by the rhizobacteria is a promising alternative to restore contaminated sites in situ. However, such processes require that plants produce the metabolites that bacteria can readily oxidize. The biphenyl dioxygenase is the first enzyme of the bacterial catabolic pathway involved in the degradation of polychlorinated biphenyls. This enzyme consists of three components: the two sub-unit oxygenase (BphAE) containing a Rieske-type iron-sulfur cluster and a mononuclear iron center, the Rieske-type ferredoxin (BphF), and the FAD-containing ferredoxin reductase (BphG). In this work, based on analyses with Nicotiana benthamiana plants transiently expressing the biphenyl dioxygenase genes from Burkholderia xenovorans LB400 and transgenic Nicotiana tabacum plants transformed with each of these four genes, we have shown that each of the three biphenyl dioxygenase components can be produced individually as active protein in tobacco plants. Therefore, when BphAE, BphF, and BphG purified from plant were used to catalyze the oxygenation of 4-chlorobiphenyl, detectable amounts of 2,3-dihydro-2, 3-dihydroxy-4'-chlorobiphenyl were produced. This suggests that creating transgenic plants expressing simultaneously all four genes required to produce active biphenyl dioxygenase is feasible. 相似文献
54.
Spíchal L Krystof V Paprskárová M Lenobel R Styskala J Binarová P Cenklová V De Veylder L Inzé D Kontopidis G Fischer PM Schmülling T Strnad M 《The Journal of biological chemistry》2007,282(19):14356-14363
Cytokinins are a class of plant hormones that regulate the cell cycle and diverse developmental and physiological processes. Several compounds have been identified that antagonize the effects of cytokinins. Based on structural similarities and competitive inhibition, it has been assumed that these anticytokinins act through a common cellular target, namely the cytokinin receptor. Here, we examined directly the possibility that various representative classical anticytokinins inhibit the Arabidopsis cytokinin receptors CRE1/AHK4 (cytokinin response 1/Arabidopsis histidine kinase 4) and AHK3 (Arabidopsis histidine kinase 3). We show that pyrrolo[2,3-d]pyrimidine and pyrazolo[4,3-d]pyrimidine anticytokinins do not act as competitors of cytokinins at the receptor level. Flow cytometry and microscopic analyses revealed that anticytokinins inhibit the cell cycle and cause disorganization of the microtubular cytoskeleton and apoptosis. This is consistent with the hypothesis that they inhibit regulatory cyclin-dependent kinase (CDK) enzymes. Biochemical studies demonstrated inhibition by selected anti-cytokinins of both Arabidopsis and human CDKs. X-ray determination of the crystal structure of a human CDK2-anticytokinin complex demonstrated that the antagonist occupies the ATP-binding site of CDK2. Finally, treatment of human cancer cell lines with anticytokinins demonstrated their ability to kill human cells with similar effectiveness as known CDK inhibitors. 相似文献
55.
Réblová M 《Mycologia》2006,98(1):68-93
The systematic position and phylogenetic relationships of Ceratostomella sensu lato and phenotypically similar fungi using comparative morphological and culture studies and phylogenetic analyses of the nuclear large- and small-subunit ribosomal DNA were explored. In the light of inferred phylogenies and morphological data the genus Ceratostomella is redescribed, the generic concept is emended and four species are accepted (viz. C. cuspidata, C. pyrenaica, C. rhynchophora and C. rostrata). A new genus Xylomelasma is introduced and delimited from Ceratostomella, with two new species described (viz. X. novaezelandiae and X. sordida). In culture species of both Ceratostomella and Xylomelasma produced sterile mycelium. The genus Lentomitella with a phaeoisaria-like anamorph formed in vitro is reinstated to encompass taxa formerly attributed to the broadly perceived Ceratostomella with three accepted species (viz. L. cirrhosa, L. crinigera and L. tomentosa). Lentomitella and Ceratostomella are clearly distinguishable by the morphology of asci, ascospores and centrum. Lentomitella is compared to phenotypically similar Ceratosphaeria, which formed a harpophora-like anamorph in vitro. In the present phylogenies Ceratostomella, Ceratosphaeria, Lentomitella and Xylomelasma are shown as clearly separate genera belonging to three different groups of perithecial ascomycetes. Ceratostomella, Lentomitella and Xylomelasma reside within a large unsupported clade consisting of members the Ophiostomatales, the freshwater Annulatascaceae and a group of nonstromatic, terrestrial taxa. Ceratosphaeria is well supported within the Magnaporthaceae. The systematic value of morphological characters of ascospores, paraphyses, asci, centrum and conidiogenesis in segregating taxa from Ceratostomella sensu lato and their relatives is discussed. 相似文献
56.
Paape M Solovyev AG Erokhina TN Minina EA Schepetilnikov MV Lesemann DE Schiemann J Morozov SY Kellmann JW 《Molecular plant-microbe interactions : MPMI》2006,19(8):874-883
The Tomato spotted wilt virus (TSWV) encoded NSm movement protein facilitates cell-to-cell spread of the viral genome through structurally modified plasmodesmata. NSm has been utilized as bait in yeast two-hybrid interaction trap screenings. As a result, a protein of unknown function, called At-4/1, was isolated from an Arabidopsis thaliana GAL4 activation domain-tagged cDNA library. Using polyclonal antibodies against bacterially expressed At-4/1, Western blot analysis of protein extracts isolated from different plant species as well as genome database screenings showed that homologues of At-4/1 seemed to be encoded by many vascular plants. For subcellular localization studies, At-4/1 was fused to green fluorescent protein, and corresponding expression vectors were used in particle bombardment and agroinfiltration assays. Confocal laser scannings revealed that At-4/1 assembled in punctate spots at the cell periphery. The protein accumulated intracellularly in a polarized fashion, appearing in only one-half of a bombarded epidermal cell, and, moreover, moved from cell to cell, forming twin-structured bodies seemingly located at both orifices of the plasmodesmatal pore. In coexpression studies, At-4/1 colocalized with a plant virus movement protein TGBp3 known to reside in endoplasmic reticulum-derived membrane structures located in close vicinity to plasmodesmata. Thus, At-4/1 belongs to a new family of plant proteins capable of directed intra- and intercellular trafficking. 相似文献
57.
58.
Penelope Koraka Byron E. E. Martina Jouke M. Roose Pieter-Paul A. M. van Thiel Geert van Amerongen Thijs Kuiken Albert D. M. E. Osterhaus 《PLoS pathogens》2012,8(5)
A fatal human case of Duvenhage virus (DUVV) infection in a Dutch traveller who had returned from Kenya was reported in 2007. She exhibited classical symptoms of rabies encephalitis with distinct pathological findings. In the present study we describe the isolation and characterization of DUVV in vitro and its passage in BALB/c mice. The virus proved to be neuroinvasive in both juvenile and adult mice, resulting in about 50% lethality upon peripheral infection. Clinical signs in infected mice were those of classical rabies. However, the distribution of viral antigen expression in the brain differed from that of classical rabies virus infection and neither inclusion bodies nor neuronal necrosis were observed. This is the first study to describe the in vitro and in vivo isolation and characterization of DUVV. 相似文献
59.
Efremova Agrafena Senzacqua Martina Venema Wiebe Isakov Evgeny Di Vincenzo Angelica Zingaretti Maria Cristina Protasoni Marina Thomski Mikhail Giordano Antonio Cinti Saverio 《Journal of physiology and biochemistry》2020,76(2):185-192
Journal of Physiology and Biochemistry - Many deleterious consequences for health of excessive fat accumulation are due to visceral fat. Browning of visceral fat is mainly cold dependent and has... 相似文献
60.
Lauren F. Messer Martin Ostrowski Martina A. Doblin Katherina Petrou Mark E. Baird Timothy Ingleton Andrew Bissett Jodie Van de Kamp Tiffanie Nelson Ian Paulsen Levente Bodrossy Jed A. Fuhrman Justin R. Seymour Mark V. Brown 《Global Change Biology》2020,26(10):5613-5629
Western boundary currents (WBCs) redistribute heat and oligotrophic seawater from the tropics to temperate latitudes, with several displaying substantial climate change‐driven intensification over the last century. Strengthening WBCs have been implicated in the poleward range expansion of marine macroflora and fauna, however, the impacts on the structure and function of temperate microbial communities are largely unknown. Here we show that the major subtropical WBC of the South Pacific Ocean, the East Australian Current (EAC), transports microbial assemblages that maintain tropical and oligotrophic (k‐strategist) signatures, to seasonally displace more copiotrophic (r‐strategist) temperate microbial populations within temperate latitudes of the Tasman Sea. We identified specific characteristics of EAC microbial assemblages compared with non‐EAC assemblages, including strain transitions within the SAR11 clade, enrichment of Prochlorococcus, predicted smaller genome sizes and shifts in the importance of several functional genes, including those associated with cyanobacterial photosynthesis, secondary metabolism and fatty acid and lipid transport. At a temperate time‐series site in the Tasman Sea, we observed significant reductions in standing stocks of total carbon and chlorophyll a, and a shift towards smaller phytoplankton and carnivorous copepods, associated with the seasonal impact of the EAC microbial assemblage. In light of the substantial shifts in microbial assemblage structure and function associated with the EAC, we conclude that climate‐driven expansions of WBCs will expand the range of tropical oligotrophic microbes, and potentially profoundly impact the trophic status of temperate waters. 相似文献