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21.
Agroinjection of tomato fruits. A tool for rapid functional analysis of transgenes directly in fruit 总被引:13,自引:0,他引:13 下载免费PDF全文
Transient expression of foreign genes in plant tissues is a valuable tool for plant biotechnology. To shorten the time for gene functional analysis in fruits, we developed a transient methodology that could be applied to tomato (Solanum lycopersicum cv Micro Tom) fruits. It was found that injection of Agrobacterium cultures through the fruit stylar apex resulted in complete fruit infiltration. This infiltration method, named fruit agroinjection, rendered high levels of 35S Cauliflower mosaic virus-driven beta-glucuronidase and yellow fluorescence protein transient expression in the fruit, with higher expression levels around the placenta and moderate levels in the pericarp. Usefulness of fruit agroinjection was assayed in three case studies: (1) the heat shock regulation of an Arabidopsis (Arabidopsis thaliana) promoter, (2) the production of recombinant IgA antibodies as an example of molecular farming, and (3) the virus-induced gene silencing of the carotene biosynthesis pathway. In all three instances, this technology was shown to be efficient as a tool for fast transgene expression in fruits. 相似文献
22.
Environmental factors affecting essential oils variability in Thymus piperella L. are studied. The relationship between the bioclimatics index and edaphic factors with three chemotypes is determined through the application of multivariate analysis (CANOCO) and other statistical processes to both ecological and the essential oil data set components. Chemotype p-cymene γ-terpinene carvacrol shows a positive relationship with the aridity index (Ia) and Altitude. The p-cymene thymol chemotype is related to factors affecting water balance in both the soils and plants. The influence of climatic factors over p-cymene carvacrol is less evident. The compound p-cymene, common to the three chemical groups and the most abundant of all, presents positive correlation with the organic matter in the soil. 相似文献
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Pere P. Simarro Giuliano Cecchi José R. Franco Massimo Paone Abdoulaye Diarra José Antonio Ruiz-Postigo Eric M. Fèvre Raffaele C. Mattioli Jean G. Jannin 《PLoS neglected tropical diseases》2012,6(10)
Background
Human African trypanosomiasis (HAT), also known as sleeping sickness, persists as a public health problem in several sub-Saharan countries. Evidence-based, spatially explicit estimates of population at risk are needed to inform planning and implementation of field interventions, monitor disease trends, raise awareness and support advocacy. Comprehensive, geo-referenced epidemiological records from HAT-affected countries were combined with human population layers to map five categories of risk, ranging from “very high” to “very low,” and to estimate the corresponding at-risk population.Results
Approximately 70 million people distributed over a surface of 1.55 million km2 are estimated to be at different levels of risk of contracting HAT. Trypanosoma brucei gambiense accounts for 82.2% of the population at risk, the remaining 17.8% being at risk of infection from T. b. rhodesiense. Twenty-one million people live in areas classified as moderate to very high risk, where more than 1 HAT case per 10,000 inhabitants per annum is reported.Discussion
Updated estimates of the population at risk of sleeping sickness were made, based on quantitative information on the reported cases and the geographic distribution of human population. Due to substantial methodological differences, it is not possible to make direct comparisons with previous figures for at-risk population. By contrast, it will be possible to explore trends in the future. The presented maps of different HAT risk levels will help to develop site-specific strategies for control and surveillance, and to monitor progress achieved by ongoing efforts aimed at the elimination of sleeping sickness. 相似文献25.
26.
Heredia-Rojas JA Caballero-Hernandez DE Rodriguez-de la Fuente AO Ramos-Alfano G Rodriguez-Flores LE 《Bioelectromagnetics》2004,25(1):63-68
The effect of in vivo exposure of mice to a 60 Hz sinusoidal magnetic field (MF) at 2.0 mT on male germ cells was studied. The cytological endpoints measured included meiotic chromosome aberrations in spermatocytes and sperm morphology. Three independent experiments were carried out: (a) animals exposed for 72 h, (b) 10 days/8 h daily, and (c) 72 h exposure to MF plus 5 mg/kg of Mitomycin-C. No statistically significant differences indicative of MF effects were observed between MF exposed and control animals. In addition, an opposite effect between MF exposure and Mitomycin-C treatment in terms of chromosomal aberrations and sperm morphology was observed. 相似文献
27.
HOTAIR role in melanoma progression and its identification in the blood of patients with advanced disease 下载免费PDF全文
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Enrico Lancellotti Mirco Iotti Alessandra Zambonelli Antonio Franceschini 《Mycorrhiza》2014,24(6):481-486
For the first time, arbutoid mycorrhizas established between Tuber borchii and Arbutus unedo were described. Analyzed mycorrhizas were from one T. borchii natural truffle ground, dominated by Pinus pinea, as well as synthesized in greenhouse conditions. A. unedo mycorrhizas presented some typical characteristics of ectomycorrhizas of T. borchii. However, as in arbutoid mycorrhizas, ramification was cruciform and intracellular colonization in epidermal cells was present. The ability of T. borchii to form ectomycorrhizas with A. unedo opens up the possibility to also use this fruit plant for truffle cultivation. This represents an important economic opportunity in Mediterranean areas by combining both the cultivation of precious truffles and the production of edible fruits which are used fresh or in food delicacies. 相似文献
30.
Antonio Di Franco Agnese Marchini Pasquale Baiata Marco Milazzo Renato Chemello 《Biodiversity and Conservation》2009,18(5):1201-1217
Scuba diving is now one of the major form of commercial use of marine protected areas (MPAs) around the world and the control
of its potential impacts on the marine environment represents a fundamental key to manage this recreational activity in highly
dived areas. A potential tool to tackle such issues has been thought to be the definition of a value of recreational carrying
capacity of an area, but this approach has been rarely considered management-effective. Therefore, the first step for effectively
managing scuba-diving should be ‘bottom-up’: characterizing the benthic communities potentially affected by diving and evaluating
their vulnerability. Aim of this paper is to propose a tool to define an index of vulnerability for dive trails (STVI: scuba
trail vulnerability index). This has taken into consideration both physical and biological features of each trail. All the
considered features are represented by non-quantitative variables, because either they are purely qualitative or their quantitative
measurement is impractical. The management of such qualitative information and its translation into a formal methodology was
performed by means of fuzzy logic, which has been repeatedly proposed as a powerful technique to develop indices of environmental
quality. The approach adopted in this study provided a useful tool for the preliminary assessment of the potential vulnerability
of benthic assemblages to scuba-diving and may represent an alternative method to the assessment of carrying capacity. The
application of this index will enable management strategies for potentially reducing the degradation of benthic organisms/assemblages,
and allowing a sustainable use of MPAs. 相似文献