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91.
Laschi S Mascini M Scortichini G Fránek M Mascini M 《Journal of agricultural and food chemistry》2003,51(7):1816-1822
In this work, a disposable electrochemical immunosensor, based on a competitive assay scheme, was applied to detect polychlorinated biphenyls (PCBs) in food. For this purpose, antibodies against PCBs were directly immobilized onto the carbon surface of a disposable screen-printed electrode. A competition between the PCBs present in the sample and a fixed concentration of an enzyme-labeled PCB was realized and evaluated by electrochemical detection. Alkaline phosphatase was used as the enzyme label, coupled with differential pulse voltammetry (DPV) as the electrochemical technique. The immunosensor was tested on aroclor mixture detection (1242 and 1248) and then on some typologies of food samples to evaluate the possible application for real sample analysis. Samples analyzed were from different matrixes, such as sheep milk, bovine adipose tissue, and bovine muscle. Results obtained were compared with the accredited results according to ISO 17025 methods for PCB detection (HRGC-LRMS) as a confirmatory analysis. Preliminary results show the possibility to use this device as a screening method in food sample analysis. The negligible matrix effect observed may lead to a simplified extraction procedure, and considerable time and consumable savings are the immediate benefits given by the proposed method. 相似文献
92.
Sanne M.J. Dolieslager Marcello P. Riggio Alan Lennon David F. Lappin Norman Johnston David Taylor David Bennett 《Veterinary microbiology》2011
Feline chronic gingivostomatitis (FCGS) is a chronic inflammatory disease of the oral cavity that causes severe pain and distress. There are currently no specific treatment methods available and little is known regarding its aetiology, although bacteria are thought to play a major role. The purpose of this study was to identify the oral bacterial flora in normal and diseased cats. Oral swabs were obtained from the palatoglossal folds of eight cats (three normal and five FCGS) and were subjected to microbiological culture. Pasteurella pneumotropica and Pasteurella multocida subsp. multocida were the most prevalent species identified by culture methods in the normal and FCGS samples, respectively. Bacteria were also identified using culture-independent methods (bacterial 16S rRNA gene sequencing). For the normal samples, 158 clones were analysed and 85 clones were sequenced. Capnocytophaga canimorsus (10.8% of clones analysed) was the predominant species. Uncultured species accounted for 8.2% of clones analysed, and 43.7% of clones analysed represented potentially novel species. For the FCGS samples, 253 clones were analysed and 91 clones were sequenced. The predominant species was P. multocida subsp. multocida (51.8% of clones analysed). Uncultured species accounted for 8.7% of clones analysed, and 4.7% of clones analysed represented potentially novel species. It is concluded that the oral flora in cats with FCGS appears to be less diverse than that found in normal cats. However, P. multocida subsp. multocida is found to be significantly more prevalent in FCGS than in normal cats and consequently may be of aetiological significance in this disease. 相似文献
93.
Riadh Ilahy Chafik Hdider Marcello S. Lenucci Imen Tlili Giuseppe Dalessandro 《Scientia Horticulturae》2011
In this study, the antioxidant components and of six high-lycopene (Lyco 1, Lyco 2, HLY 02, HLY 13, HLY 18 and Kalvert) and one ordinary (Donald) tomato cultivars (cvs) grown simultaneously in an open-field of the Southern Italy were investigated. Lycopene, β-carotene, lutein, total phenols, flavonoids, ascorbic acid (AsA), dehydroascorbic acid (DHA) and total vitamin C (AsA + DHA) contents, as well as hydrophilic and lipophilic antioxidant activities (HAA and LAA) were determined. Significant differences were detected among tomato cvs in all studied antioxidant components, as well as in the antioxidant activity of their hydrophilic and lipophilic fractions. High-lycopene tomato cvs showed higher lycopene, β-carotene, HAA and LAA when compared to cv Donald. Cv HLY 18 showed the highest lycopene and β-carotene content with 232.9 mg/kg fresh weight (fw) and 19.4 mg/kg fw, respectively. Except for Kalvert, high-lycopene tomato cvs also obtained higher total vitamin C levels, with cv HLY 13 top ranking with an average of 352.8 mg/kg fw. LAA ranged from 133.5 μM Trolox/100 g fw in cv Donald to 540.1 μM Trolox/100 g fw in cv Lyco 2 and was significantly correlated to lycopene (r = 0.53; p < 0.01) and β-carotene (r = 0.56; p < 0.01) contents. A variation between 2.7- and 4.0-fold was found in LAA of high-lycopene tomato cvs compared to Donald. HAA was significantly correlated to the amount of DHA (r = 0.61; p < 0.01) and total vitamin C (r = 0.60; p < 0.01). Although these data require confirmation over a longer period of time, this investigation suggests a promising use of the high-lycopene tomato cvs for the production of tomatoes with higher nutritional quality. 相似文献
94.
Sanne Maria Johanna Dolieslager David Francis Lappin David Bennett Libby Graham Norman Johnston Marcello Pasquale Riggio 《Veterinary immunology and immunopathology》2013,151(3-4):263-274
Feline chronic gingivostomatitis (FCGS) is an inflammatory disease of the oral cavity that causes severe pain and distress in affected cats. Treatment methods are currently very limited. The aims of this study were to assess the feline innate immune response by investigating the levels of cytokine and Toll-like receptor (TLR) mRNAs in tissue biopsies of cats with and without FCGS, and to relate this to the presence or absence of putative oral pathogens identified previously within these cats. Mucosal biopsies were collected from 28 cats with FCGS and eight healthy cats. The levels of TLR (TLR2, TLR3, TLR4, TLR7, TLR9) and cytokine (IL-1β, IL-4, IL-6, IL-10, IL-12, TNF-α, IFN-γ) mRNA was determined using quantitative PCR. In the FCGS group a statistically significant increase was seen in TLR2, TLR7, TNF-α, IFN-γ, IL-1β and IL-6 mRNA levels compared to the healthy group. In cats where Tannerella forsythia was present, statistically significant increases were seen in TLR2, TLR4, TLR7, TLR9, TNF-α and IL-1β mRNA levels compared to cats where this putative pathogen was absent. Statistically significant increases in mRNA expression were also seen in cats harbouring feline calicivirus (FCV) (TLR2, IL-1β, IL-6, IFN-γ) and Porphyromonas circumdentaria (TLR2, TLR3) compared to cats where these putative pathogens were absent. Pasteurella multocida subsp. multocida and Pseudomonas sp. did not significantly alter the expression of any TLR or cytokine mRNAs when compared to animals who tested negative for these species, while cats colonised with P. multocida subsp. septica demonstrated a statistically significant reduction in the expression of TLR7, TNF-α and IFN-γ mRNAs compared to cats free of this species. The expression of mRNA for several TLRs and cytokines is elevated in FCGS. A positive correlation was observed between clinical disease severity and the presence of FCV (p = 0.001; Rho = 0.58). Although the number of cats harbouring T. forsythia was low by comparison, 80% of samples in which it was present were from cases with the highest clinical disease severity. Positive correlations with clinical disease severity were seen for TLR2 (p = 0.00086), TLR7 (p = 0.049), TNF-α (p = 0.027), IFN-γ (p = 0.0015), IL-1β (p = 0.004) and IL-6 (p = 0.00001) mRNAs. The putative pathogens FCV and T. forsythia may be important in stimulating a host immune response to FCGS and may play a role in the pathogenesis of this disease. 相似文献
95.
The total carbohydrate content of the intact pulp of Spondias cytherea was 41%. Polysaccharides were obtained via hot aqueous extraction after defatting with organic solvents. The aqueous extract was treated with excess ethanol to form a precipitate, which was then solubilized in water. The material precipitated upon acidification when HCl was removed. The resulting supernatant fraction was submitted to freeze-thawing treatment yielding a soluble fraction (sFTS). This fraction had Ara, Rha, Gal and GalA in its structure as determined by GC-MS. 13C NMR analysis showed signals assigned to alpha-L-Araf, beta-D-Galp, alpha-D-GalpA and alpha-L-Rhap units, in addition to galacturonic acid units, which were present also as methyl ester. These results suggest a type I rhamnogalacturonan with arabinogalactan branches. Cell eliciting activity in a dose-depending pattern was observed in vitro on peritoneal macrophages treated with sFTS. 相似文献
96.
Iriti M Rossoni M Borgo M Ferrara L Faoro F 《Journal of agricultural and food chemistry》2005,53(23):9133-9139
Field treatments of grapevine (cv. Merlot) with the plant activator benzothiadiazole (BTH, 0.3 mM) induced resistance against gray mold caused by Botrytis cinerea. Both incidence and severity of the disease were reduced. The resistance was associated with an increase of total polyphenols in berry skins, in particular, the proanthocyanidin fraction, that increased up to 36%. The amino acid profile of leaves was also modified by treatments, particularly lysine, that augmented 4-fold. Other amino acids involved in resistance mechanisms to either biotic or abiotic stress increased as well. These results indicate that BTH treatments can be used to control gray mold, thereby limiting an excessive use of fungicides, and could be exploited to increase the content of micronutrients of high nutritional value, arising from both primary and secondary metabolisms. 相似文献
97.
The ammonia flux from a green manured field was measured at a site in southern Italy. The green manure was provided by ploughing in about 66 and 78 t ha−1 of broad beans at the flowering stage during the spring in 1995 and 1996. The NH3 flux was estimated by means of the micrometeorological simplified aerodynamic method with the ammonia concentration measured at two levels above soil surface. Ammonia concentration was measured over a 2–3 h sampling period by trapping air NH3 in a H2SO4 solution and analysing this sample in the laboratory with the colorimetric method using the Nessler solution. About 70% of the total amount of ammonia was emitted in the first two days immediately after manuring. The NH3 flux was regulated by the same mechanism as the water vapour transport. Seventy percent of the daily ammonia was emitted around noon. The ammonia emission stopped during rainy and cold days and started again as soon as solar radiation, soil and air temperature increased, following plant decomposition. The total amount of ammonia emitted in the experimental period (28 days in 1995 and 18 days in 1996) was about 13 kg ha−1 for both years. 相似文献
98.
Massimo Genovese Concetta Imperatore Marcello Casertano Anna Aiello Francesco Balestri Lucia Piazza Marialuisa Menna Antonella Del Corso Paolo Paoli 《Marine drugs》2021,19(10)
An in-depth study on the inhibitory mechanism on protein tyrosine phosphatase 1B (PTP1B) and aldose reductase (AR) enzymes, including analysis of the insulin signalling pathway, of phosphoeleganin, a marine-derived phosphorylated polyketide, was achieved. Phosphoeleganin was demonstrated to inhibit both enzymes, acting respectively as a pure non-competitive inhibitor of PTP1B and a mixed-type inhibitor of AR. In addition, in silico docking analyses to evaluate the interaction mode of phosphoeleganin with both enzymes were performed. Interestingly, this study showed that phosphoeleganin is the first example of a dual inhibitor polyketide extracted from a marine invertebrate, and it could be used as a versatile scaffold structure for the synthesis of new designed multiple ligands. 相似文献
99.
Ariadne Missono Brondi Josiane Souza Pereira Daniel Vitor Xavier Monteiro de Castro Jerusa Simone Garcia Marcello Garcia Trevisan 《Communications in Soil Science and Plant Analysis》2016,47(22):2506-2513
Humic substances are the main responsible for soil conditioning and are one of the major components of the composting product. However, there is still little information about their composition and mechanisms of activity. This study aimed to evaluate quantitatively the humic and fulvic fraction by size-exclusion liquid chromatography and the metal content by atomic absorption spectrometry. The chromatographic method used was efficient for humic and fulvic acids quantitation. Levels of 1.73 ± 0.03 and 1.6 ± 0.5 g kg?1 were found for chicken manure regarding humic and fulvic acids, respectively, and 5.1 ± 0.9 and 1.2 ± 0.1 g kg?1 for peat. The metal contents indicated the need of a mineral enrichment, because only the levels of iron reached the minimum recommended by legislation. It was also observed that evaluated organic fertilizers were in accordance with the specifications established by legislation in relation to carbon and total nitrogen and the pathogen levels. 相似文献
100.
Marcello Donatelli Gianni Bellocchi Ephrem Habyarimana Roberto Confalonieri Fabio Micale 《Computers and Electronics in Agriculture》2009,69(2):165-170
Wind is a library providing a collection of stochastic approaches to generate wind speed data on daily and hourly time steps. Daily generation refers to as mean, maximum and minimum daily wind speed. The library is made available as software component, inclusive of hypertext help file, allowing the development of language-independent clients under Windows operating systems. The component includes advanced features for re-use in custom developed applications, and it allows independent extensions by third parties without requiring its re-compilation. Illustrative examples on how to extend and re-use the library are provided as C# code projects. 相似文献