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61.
Ochratoxin A (OTA), is a nephrotoxic mycotoxin present in wine, which is nephrotoxic in humans. Our working hypothesis is that natural substances in wine may counteract OTA toxicity. Thirty-six rats were randomized to OTA dissolved in saline, red wine, or 13.5% ethanol or to OTA-free wine, ethanol, or saline. OTA (289 microg/kg of body weight/48 h) was administered by gastric gavage for 2 weeks. Serum creatinine, tubular enzymuria, renal lipohydroperoxides (LOOH), reduced (GSH) and oxidized (GSSG) glutathione, and renal superoxide dismutase activity (SOD) were determined in renal tissue. OTA alone produced significant increases in renal lipoperoxides and significant decreases in SOD and GSH/GSSG ratio. In red wine or ethanol, OTA was less nephrotoxic, reducing oxidative damage as revealed by LOOH. In OTA-wine and OTA-ethanol groups, SOD activity was higher than in the OTA-treated one, suggesting that both ethanol and nonalcoholic fractions may preserve antioxidant reserve. GSH/GSSG ratio was significantly preserved only in the OTA-wine group and not in OTA-ethanol. Red wine may exert a protective effect against OTA nephrotoxicity by limiting oxidative damage. The ostensible protection afforded by ethanol deserves further investigation.  相似文献   
62.
Gravimetric lipid determination is a major parameter for the characterization and the authentication of royal jelly quality. A solid/liquid extraction was compared to the reference method, which is based on liquid/liquid extraction. The amount of royal jelly and the time of the extraction were optimized in comparison to the reference method. Boiling/rinsing ratio and spread of royal jelly onto the extraction thimble were identified as critical parameters, resulting in good accuracy and precision for the alternative method. Comparison of reproducibility and repeatability of both methods associated with gas chromatographic analysis of the composition of the extracted lipids showed no differences between the two methods. As the intra-laboratory validation tests were comparable to the reference method, while offering rapidity and a decrease in amount of solvent used, it was concluded that the proposed method should be used with no modification of quality criteria and norms established for royal jelly characterization.  相似文献   
63.
Phytoremediation is an emerging technology based on the use of green plants to remove, contain, inactivate or destroy harmful environmental pollutants. Recent developments in Europe and the USA show that the approach is somewhat different on both sides of the Atlantic. In Europe, phytoremediation has more basically been research driven and, based on the outcomes, applications have been envisaged. By contrast, the approach in the USA is more application and experience driven. In spite of a growing track record of commercial success, more demonstration projects are needed to prove that phytoremediation is effective in order to rigorously measure its underlying economics, and to expand its applications. More fundamental research is also required to better understand the complex interactions between pollutants, soil, plant roots and micro-organisms at the rhizosphere level, to increase the bioavailability of pollutants, to fully exploit the metabolic diversity of plants and, thus, to successfully implement this new green technology.  相似文献   
64.
In the present study, included within the framework of a Franco-German Research Program for Conservation of HistoricalMonuments, the chemical composition of rainwater was investigated in Thann (Alsace, France) and in Tours (Indre etLoire, France) between 1992 and 1993. A total of 78 and 24samples, respectively, were collected, near the Thann collegiateand the Tours cathedral on a weekly basis and analysed for Cl-, NO3 -, SO4 2-, Na+, NH4 +, K+, Mg2+ and Ca2+. Results showpH ranged from 3.60 to 6.58 and from 5.49 to 7.01 for Thann andTours, respectively. In Thann, SO4 2- is the major anion and rainwater acidity is neutralised by compounds ofterrigenic origin which come from the soil of the upper Rhinevalley (Ca2+; ‘loess’) and the potash mines of Alsace. In Tours, SO4 2- is also the major anion and the acidity is neutralised partially by atmospheric ammonia and partially by compounds of terrigenic origin and by dust fromthe erosion of the cathedral and the works of restoration, in the form of CaCO3.  相似文献   
65.
This study presents the development of a core collection capturing the genetic diversity of a collection of 350 tetraploid cultivated potato varieties (Solanum tuberosum L.). The core collection was established by using simple sequence repeats (SSR) data and the M strategy, which aims at maximizing the allelic diversity. A 48-core collection was defined which captured 99.5% of the SSR alleles used to establish it, and 96.9% of the SSR alleles which belonged to an independent set of markers. The defined core collection was further validated by analysing 35 agro-morphological traits. The class coverage value and the estimates of the Shannon-Weaver diversity index indicated a good representation of the phenotypic diversity in the core collection. Furthermore, the core set included accessions having the most desirable status for several agronomic traits. A linkage disequilibrium (LD) analysis, using data obtained with the SolCAP SNP array on the defined core collection, was performed. The population structure analysis showed that the core collection did not present a clear genetic structure. The linkage disequilibrium analysis carried out between markers located on the same pseudomolecule within 10,000 bp concluded that 41.3% of these pairs of SNP markers have a significant LD. We conclude that this core collection, representative of the genetic diversity of cultivated potato varieties, is a relevant tool for a first screening for genetic variation regarding novel traits of interest.  相似文献   
66.
Salmonella enterica causes a variety of diseases, including gastroenteritis and typhoid fever. The success of this pathogen depends on its capacity to proliferate within host cells in a membrane-bound compartment. We found that the Salmonella-containing vacuole recruited the plus-end-directed motor kinesin. Bacterial effector proteins translocated into the host cell by a type III secretion system antagonistically regulated this event. Among these effectors, SifA targeted SKIP, a host protein that down-regulated the recruitment of kinesin on the bacterial vacuole and, in turn, controlled vacuolar membrane dynamics.  相似文献   
67.

Background  

Marine turtles deposit their eggs on tropical or subtropical beaches during discrete nesting seasons that span several months. The number and distribution of nests laid during a nesting season provide vital information on various aspects of marine turtle ecology and conservation.  相似文献   
68.
In Dakar kennels where morbidity and mortality attributed to diseases transmitted by ticks were high, we conducted a field study to assess the prevalence of Ehrlichia canis, Anaplasma platys and Babesia spp. infections in two kennels (n = 34 dogs) and to study the impact of tick protection. The first day of the study, the E. canis PCR were positive in 18 dogs (53%). A. platys was found in one dog and all dogs were negative for Babesia spp. After one month of doxycycline treatment, the number of PCR positive dogs decreased significantly to 2 (5.9%). During seven months, all dogs were treated monthly topically with a novel combination (Certifect®, Merial) delivering at least 6.7 mg fipronil/kg body weight, 8.0 mg amitraz/kg and 6 mg (S)-methoprene/kg. The number of PCR positive dogs remained stable all over the seven months, with 4 dogs being positive at Day 90 and 2 at Day 210. The combination of treatment and monthly prevention had a significant effect in the two kennels. All dogs remained healthy, which was not the case in previous years.  相似文献   
69.
Breeding to improve perennial grasses for forage usage aims to increase the whole-plant aerial biomass. However, the ability to increase the whole-plant yield by breeding may be questionable in grasses which are expected to reach an optimal leaf area index during grass stand growth rather rapidly. We carried out a field experiment aiming to compare herbage yield and other performances of seven natural populations and 21 cultivars of diploid perennial ryegrass registered on European National lists in the last 40 years. Cultivars were sampled in the spike emergence earliness range used for pasture usage, i.e. in the semi-late and late earliness range according to the French classification into spike emergence earliness groups. Forage performances of populations and cultivars were tested in four locations in monthly cut dense sward plots. Morphological and phenological traits were recorded in two spaced-plant experiments, and seed yield was assessed in two locations in standard seed production conditions. Trait regression on cultivar registration year pointed out that total dry-matter yield of cultivars increased by +3.2% per decade. However, dry-matter yield was not improved in the most favourable period for grass growth, i.e. in spring. On the other hand, it was improved in summer (+2.8% per decade) and autumn (+7.4% per decade) when the aerial biomass production is on average rather small. Breeders succeeded in significantly reducing aftermath heading. Reduction in aftermath heading is likely to have contributed to the noted increase in summer and autumn dry-matter yields, and to a moderate improvement in herbage feeding value. Breeding was also efficient in improving rust resistance and in bringing forward the start of spring growth. For monthly cut swards, we evidenced a clear association of leaf and lamina lengths with spring and summer dry-matter yields. Breeding for long leaves, or for high leaf elongation rate, should contribute to improve the cumulated intercepted radiation during re-growths, and consequently could be a way of improving the spring dry-matter yield. Seed yield did not improve with breeding for forage performances. However, we did not notice any negative association between the seed yield and traits related with forage usage. Direct selection pressures on seed yield criteria applied at the core of the breeding process should enable to improve the seed yield without any negative impact on forage performances.  相似文献   
70.
Wood production represents a large but variable fraction of gross primary production (GPP) in highly productive Eucalyptus plantations. Assessing patterns of carbon (C) partitioning (C flux as a fraction of GPP) between above- and belowground components is essential to understand mechanisms driving the C budget of these plantations. Better knowledge of fluxes and partitioning to woody and non-woody tissues in response to site characteristics and resource availability could provide opportunities to increase forest productivity. Our study aimed at investigating how C allocation varied within one apparently homogeneous 90 ha stand of Eucalyptus grandis (W. Hill ex Maiden) in Southeastern Brazil. We assessed annual above-ground net primary production (ANPP: stem, leaf, and branch production) and total belowground C flux (TBCF: the sum of root production and respiration and mycorrhizal production and respiration), GPP (computed as the sum of ANPP, TBCF and estimated aboveground respiration) on 12 plots representing the gradient of productivity found within the stand. The spatial heterogeneity of topography and associated soil attributes across the stand likely explained this fertility gradient. Component fluxes of GPP and C partitioning were found to vary among plots. Stem NPP ranged from 554 g C m(-2) year(-1) on the plot with lowest GPP to 923 g C m(-2) year(-1) on the plot with highest GPP. Total belowground carbon flux ranged from 497 to 1235 g C m(-2) year(-1) and showed no relationship with ANPP or GPP. Carbon partitioning to stem NPP increased from 0.19 to 0.23, showing a positive trend of increase with GPP (R(2) = 0.29, P = 0.07). Variations in stem wood production across the gradient of productivity observed at our experimental site were a result of the variability in C partitioning to different forest system components.  相似文献   
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