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211.
212.
Vincenzo Candido Trifone D’Addabbo Vito Miccolis Donato Castronuovo 《Phytoparasitica》2012,40(2):185-194
The effect of four solarizing plastic materials on weed suppression and yield response of two lettuce cultivars (‘Bacio’ and
‘Moringa’) grown during two consecutive seasons was investigated at Metaponto (40°23′N; 16°47′E; 10 m a.s.l.), southern Italy.
All solarization treatments suppressed winter and summer weeds with no significant difference among the plastic materials,
although biodegradable film was less efficient in controlling common purslane and common amaranth. Weed infestation at the
harvest of both lettuce cultivars was not affected by the solarizing material, whereas fewer weeds were found in the plots
grown with ‘Bacio’ than with ‘Moringa’. Lettuce yield in two successive growing seasons was always significantly higher in
solarized plots than in nontreated control, without any statistical difference among the plastic materials. Yield and head
quality of cv. ‘Bacio’ were higher than ‘Moringa’ in the first growing season, but the opposite occurred in the second crop.
Soil solarization was confirmed to be effective for weed management in field lettuce crops in the Mediterranean areas, although
weed suppression may be affected also by the lettuce cultivar. Choice of solarizing materials, when similarly effective on
weeds and crop yield, should take into account also their cost. Low density polyethylene plastics emerged as the best choice
in conventional lettuce crops as highly effective as, and less expensive than the other materials, whereas the use of biodegradable
films should be limited to organic lettuce systems. 相似文献
213.
Sara Carpi Egeria Scoditti Beatrice Polini Simone Brogi Vincenzo Calderone Peter Proksch Sherif S. Ebada Paola Nieri 《Marine drugs》2022,20(7)
The natural environment represents an important source of drugs that originates from the terrestrial and, in minority, marine organisms. Indeed, the marine environment represents a largely untapped source in the process of drug discovery. Among all marine organisms, sponges with algae represent the richest source of compounds showing anticancer activity. In this study, the two secondary metabolites pelorol (PEL) and 5-epi-ilimaquinone (EPI), purified from Dactylospongia elegans were investigated for their anti-melanoma activity. PEL and EPI induced cell growth repression of 501Mel melanoma cells in a concentration- and time-dependent manner. A cell cycle block in the G1 phase by PEL and EPI was also observed. Furthermore, PEL and EPI induced significant accumulation of DNA histone fragments in the cytoplasmic fraction, indicating a pro-apoptotic effect of both compounds. At the molecular level, PEL and EPI induced apoptosis through the increase in pro-apoptotic BAX expression, confirmed by the decrease in its silencing miR-214-3p and the decrease in the anti-apoptotic BCL-2, MCL1, and BIRC-5 mRNA expression, attested by the increase in their silencing miRNAs, i.e., miR-193a-3p and miR-16-5p. In conclusion, our data indicate that PEL and EPI exert cytotoxicity activity against 501Mel melanoma cells promoting apoptotic signaling and inducing changes in miRNA expression and their downstream effectors. For these reasons could represent promising lead compounds in the anti-melanoma drug research. 相似文献
214.
Bonetti A Marotti I Catizone P Dinelli G Maietti A Tedeschi P Brandolini V 《Journal of agricultural and food chemistry》2004,52(13):4080-4089
Wheat quality criteria continually evolve in response to market pressure and consumer preference. Characterization of cereal cultivars for quality and agronomic properties, have widely shown the importance of the protein content to ensure good quality products. The aim of this work is a comparison of reversed-phase high performance liquid chromatography (RP-HPLC) and free zone capillary electrophoresis (FZCE) in the identification of Italian wheat cultivars and detection of durum wheat flour adulteration. Mainly alcohol soluble (gliadins) and water soluble (albumins) proteins were extracted from 14 common wheat cultivars and from 9 durum wheat cultivars. In RP-HPLC chromatograms, wheat albumins and gliadins eluted between 3 and 9 min and between 10 and 42 min, respectively. Even if the chosen chromatographic conditions (reversed phase) did not permit a complete resolution of hydrophilic proteins such as albumins, a good reproducibility was observed for both albumins and gliadins. In FZCE electropherograms, wheat albumins and gliadins migrated between 8 and 14 min and 16-25 min, respectively. A good reproducibility was found for wheat albumins, while the relatively poor reproducibility of gliadin fractions was a consequence of the selected separation conditions aimed to separate in the same run either hydrophilic (albumins) and alcohol-soluble (gliadins) proteins. The principal component analysis (PCA) of HPLC and FZCE data evidenced that both techniques allowed the univocal identification of the great proportion of investigated wheat cultivars. Three peaks were exclusively detected in RP-HPLC chromatograms of common wheat cultivars, while three unique peaks were found in FZCE electropherograms of common wheat cultivars. These peaks were investigated as a basis for detecting and estimating the adulteration of durum wheat flour with flour from common wheat. The direct relationship between the area of the peaks and adulteration level enabled standard curves to be constructed. The standard curves showed that adulteration may be quantified by either RP-HPLC or FZCE. 相似文献
215.
216.
Capocchi A Fontanini D Muccilli V Cunsolo V Saviozzi F Saletti R Lorenzi R Foti S Galleschi L 《Journal of agricultural and food chemistry》2005,53(20):7976-7984
Isoforms of nonspecific lipid-transfer protein 1 (nsLTP1) and nonspecific lipid-transfer protein 2 (nsLTP2) were investigated in bran tissues isolated from caryopses of two cereal crops quite relevant for the Italian market, the cultivar Centauro of soft wheat (Triticum aestivum) and Italian emmer or farro (Triticum dicoccon Schrank). By sequential separation of the bran extracts on cation-exchange and gel filtration chromatographies, fractions containing only proteins belonging to the nsLTP1 and nsLTP2 classes were obtained. The proteins were roughly identified by SDS-PAGE and by immunoreactions in Western blotting experiments. By MALDI-MS and RP-HPLC/ESI-MS analyses we were able to show the presence of several LTP1 and LTP2 isoforms in the investigated species. Bioinformatic searches based on the determined Mr indicated that (i) two nsLTP1s already identified in T. aestivum have Mr and number of Cys residues identical to that of a 9.6 kDa protein present both in soft wheat cv. Centauro and in farro; (ii) two isoforms of nsLTP2 detected in T. aestivum have the same Mr and number of Cys residues of two 7 kDa proteins found in Centauro; and (iii) a nsLTP1 detected in Ambrosia artemisiifolia has Mr and number of Cys residues coincident to that of a 9.9 kDa protein found both in soft wheat cv. Centauro and in farro. 相似文献
217.
Crop simulation models are increasingly used to evaluate the effect of alternative agricultural practices on crop yields and the environment. Difficulty in obtaining concise field data often requires that simulation results reflect a single point assumed to represent average field condition. Results of this study indicate that the single point analysis can have significant effects upon estimates of nitrogen leaching and crop yield under various surface irrigation practices. Practices considered illustrate the effects of differences in infiltration along the row, between irrigations, and between irrigated sets. Attempts to add intermediate realism in describing the irrigation system may not improve yield and leaching estimates over the single point simulation when compared to simulation results where even more realism is introduced. 相似文献
218.
Dupuy J Sutra JF Alvinerie M Rinaldi L Veneziano V Mezzino L Pennacchio S Cringoli G 《Veterinary parasitology》2008,157(3-4):284-290
The pharmacokinetics and mammary excretion of moxidectin and eprinomectin were determined in water buffaloes (Bubalus bubalis) following topical administration of 0.5mgkg(-1). Following administration of moxidectin, plasma and milk concentrations of moxidectin increased to reach maximal concentrations (C(max)) of 5.46+/-3.50 and 23.76+/-16.63ngml(-1) at T(max) of 1.20+/-0.33 and 1.87+/-0.77 days in plasma and milk, respectively. The mean residence time (MRT) were similar for plasma and milk (5.27+/-0.45 and 5.87+/-0.80 days, respectively). The AUC value was 5-fold higher in milk (109.68+/-65.01ngdayml(-1)) than in plasma (23.66+/-12.26ngdayml(-1)). The ratio of AUC milk/plasma for moxidectin was 5.04+/-2.13. The moxidectin systemic availability (expressed as plasma AUC values) obtained in buffaloes was in the same range than those reported in cattle. The faster absorption and elimination processes of moxidectin were probably due to a lower storage in fat associated with the fact that animals were in lactation. Nevertheless, due to its high excretion in milk and its high detected maximum concentration in milk which is equivalent or higher to the Maximal Residue Level value (MRL) (40ngml(-1)), its use should be prohibited in lactating buffaloes. Concerning eprinomectin, the C(max) were of 2.74+/-0.89 and 3.40+/-1.68ngml(-1) at T(max) of 1.44+/-0.20 and 1.33+/-0.0.41 days in plasma and milk, respectively. The MRT and the AUC were similar for plasma (3.17+/-0.41 days and 11.43+/-4.01ngdayml(-1)) and milk (2.70+/-0.44 days and 8.49+/-3.33ngdayml(-1)). The ratio of AUC milk/plasma for eprinomectin was 0.76+/-0.16. The AUC value is 20 times lower than that reported in dairy cattle. The very low extent of mammary excretion and the milk levels reported lower than the MRL (20ngml(-1)) supports the permitted use of eprinomectin in lactating water buffaloes. 相似文献
219.
Mohamed K.Abdelmegeid Ahmed A.Elolimy Zheng Zhou Vincenzo Lopreiato Joshua C.Mc Cann Juan J.Loor 《畜牧与生物技术杂志(英文版)》2018,(2)
Background: Extensive degradation of amino acids in the rumen via microbial deamination decreases the postruminal availability of dietary indispensable amino acids. Together with the normal decrease in voluntary dry matter intake(DMI) around parturition in dairy cows, microbial metabolism contributes to a markedly negative balance of indispensable amino acids, including methionine which may be the first-limiting for milk production. The main objective of the current study was to profile changes in major bacterial species with key functions in cel ulose and hemicel ulose digestion, xylan breakdown, proteolytic action, propionic acid production, lactate utilization and ruminal biohydrogenation in cows supplemented with rumen-protected Methionine(SM; Smartamine M, Adisseo NA, Alpharetta,GA, USA) from-23 through 30 d relative to parturition. Because ~90% of the methionine in SM bypasses the rumen,~10% of the methionine is released into the rumen and can be utilized by microbes.Results: As expected, there was an increase in overall DMI after parturition(Day, P 0.05) during which cows consumed on average 19.6 kg/d versus 13.9 kg/d in the prepartum period. The postpartum diet contained greater concentrations of lipid and highly-fermentable carbohydrate from corn grain, which likely explains the increases in the relative abundance of Anaerovibrio lipolytica, Megasphaera elsdenii, Prevotella bryantii, Selenomonas ruminantium,Streptococcus bovis, and Succinimonas amylolytica. Despite similar DMI prepartum, cows fed SM had greater(Treatment × Day, P 0.05) abundance prepartum of Fibrobacter succinogenes, Succinimonas amylolytica, and Succinivibrio dextrinosolvens. However, the greater DMI in cows fed SM after parturition(19.6 kg/d versus 13.9 kg/d) was associated with lower abundance of Fibrobacter succinogenes(2.13 × 10-3 versus 2.25 × 10-4) and Selenomonas ruminantium(2.98 × 10-1 versus 4.10 × 10-1). A lower abundance(Day, P 0.05) was detected on d 20 compared with d-10 for Fibrobacter succinogenes and Succinivibrio dextrinosolvens. The relative abundance of Butyrivibrio proteoclasticus and Eubacterium ruminantium was stable across treatment and time.(Continued from previous page)Conclusions: In diets with proper balance of rumen-degradable protein and fermentable carbohydrate, the smal fraction of Methionine released from the rumen-protected supplement did not seem to compromise growth of major bacterial species in the rumen. In fact, it had a positive effect on 3 major species prepartum when DMI was similar between groups. Because the actual requirements of Methionine(and Lysine, for example) by the cow during the transition period are unknown, it appears warranted to study the rumen microbiome as it relates to supply of rumen-protected amino acids. 相似文献
220.
Cortese L Pelagalli A Piantedosi D Mastellone V Di Loria A Lombardi P Ciaramella P Avallone L 《Veterinary journal (London, England : 1997)》2008,177(3):405-410
Thirty dogs naturally infected with Leishmania infantum were studied in order to determine the effects of treatment on haemostatic function. The animals were divided randomly into two treatment groups: Group 1 received meglumine antimoniate and allopurinol; Group 2 dogs were given the same treatment plus prednisone. Ten healthy animals were used as untreated controls. Clinical examination and determination of platelet aggregation, coagulation factors and biochemical parameters were undertaken before treatment and after 15, 30 and 60 days. A significant improvement in platelet aggregation was detected after 60 days in Group 1, but only after 15 days in Group 2. In both treated groups, platelet aggregation was lower than in the control group at the end of the study. The results suggest that prednisone may be a useful tool in the treatment of haemostatic disorders during canine leishmaniosis. The potential benefits and risks due to the use of corticosteroids in the treatment of leishmaniosis are discussed. 相似文献