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121.
122.
In this paper we present an innovative device designed and constructed to improve the fumigation process for stored foodstuffs with the use of phosphine gas in sealed chambers. The device allowed a considerable reduction in phosphine production time (from about 5 to 7 days for traditional systems to 2 days for the equipment considered), maintaining the system below the inflammability threshold, and at the same time achieving the total exhaustion of aluminum (or magnesium) phosphide so as to avoid toxic residues at the end of the process. With the standard device currently available on the market, after the normal 5-7 day fumigating period, the powder residue contains as much as 1-2% (w/w) of phosphide. Thus the residues, according to current legislation, have to be considered toxic and harmful. To overcome this disadvantage, appropriate modifications were made to the cylindrical tray used for the fumigation process: a nebulizer was installed, which has the function of increasing the moisture of the air spreading around the phosphide pellets and allowing a more rapid reaction with phosphide. Moreover, the cylindrical tray was also heated by means of an electrical resistance, and temperature was checked by a thermostat, so as to always obtain the same efficiency, independently of outside temperature, for both hot and cold periods, since reaction speed depends on the system temperature considered. In addition, a control device for air saturation allows condensation processes to be avoided. Using the modified cylindrical tray we performed tests to determine the best values of humidity and temperature for the process concerned, avoiding phosphine concentrations that might result in a fire hazard, and the remixing of phosphide pellets inside the cylindrical tray. Our experimental data allowed us to obtain a mathematical model used to gain an insight into the process in question.  相似文献   
123.

Brachychiton species are planted in Italy as ornamental trees. A survey in a nursery in Sicily (Italy) revealed the presence of young B. acerifolius and B. populneus showing severe trunk cankers, massive gummosis from the bark cracks, wood discolouration, and twig dieback. Morphological characterization was based on conidia measurement, and molecular characterization was carried out performing phylogenetic analysis (Maximum Parsimony) based on multi-locus approach of partial ITS, EF-1α, and tub2. Identification of the causal agent resulted in Neofusicoccum parvum (Botryosphaeriaceae). Pathogenicity tests were conducted in order to fulfill the Koch’s postulates. Five and three-years-old potted Brachychiton plants were inoculated (indoor and outdoor) using mycelial plugs. All the inoculated plants showed severe symptoms similar of those observed in the nursery during the survey. Some of the inoculated plants were completely dead. Re-isolations fully confirmed the causal agent. For our knowledge, this is the first report worldwide of N. parvum attacking Brachychiton spp.

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124.
Ketorolac (KET) is a nonsteroidal anti-inflammatory drug for human use, with a potent analgesic activity, that is used in the relief of moderate-to-severe postoperative pain. The pharmacokinetics of KET tromethamine was evaluated after single IV injection at 0.5 mg/kg body weight, after intubation and 10 minutes before surgery, to six Arabian colts undergoing orchiectomy. Intraoperative cardiorespiratory variables were monitored. Blood samples were collected for 36 hours, and serum samples were analyzed by high performance liquid chromotography with ultraviolet-visible detection. During surgery, all monitored physiological parameters were stable. Intermittent positive pressure ventilation, and normocapnia were maintained throughout the procedure in all animals. No adverse effects were observed. The kinetics of KET was described by a two-compartment models, and also a noncompartmental analysis was performed. The distribution and elimination half-lives were t1/2λ1t1/2λ1 0.06 ± 0.02 and t1/2λ2t1/2λ2 0.59 ± 0.21 hours, respectively. Body clearance and mean residence time were 339.99 ± 120.19 mL/h/kg and 0.49 ± 0.22 hours, respectively. The volume of distribution at steady state and volume of distribution based on the terminal phase were 218.83 ± 134.26 mL/kg and 522.5 ± 529.3 mL/kg, respectively. The serum protein binding was 75.8 ± 2.9%. The results indicate that KET at 0.5 mg/kg IV was very rapidly eliminated and thus was likely not effective in the postoperative period. However, further studies including a control group and at higher doses are suggested to investigate the KET kinetics and the analgesic efficacy in horse and define the most appropriate dosage scheme.  相似文献   
125.
The pathogenesis of encephalomyocarditis (EMC) due to the EMC virus (EMCV) was studied in 24 piglets oro-nasally infected with the field isolate B279/95. Two pigs were kept as negative controls and were euthanised at hour 0. The remaining 24 were euthanised every 6 h up to 78-h post infection (hpi). Virus isolation, histological examination and EMCV immunodetection were performed on the spleen, intestine, pancreas, liver, kidneys, heart, lungs, lymph nodes, tonsils and brain. EMCV was isolated at 6-hpi from the intestine and lymph nodes and at 12-hpi from the heart. From 6 to 12-hpi, scattered degenerate myocardiocytes were immunolabelled. Subsequently, myocarditis developed and progressively worsened. Immunopositive reaction in tonsil macrophages, observed in the early stage of infection (6-hpi), suggests that tonsils are the portal of entry, and by mean of wandering macrophages the EMC virus is then distributed through the body. Afterwards, EMCV-B279/95 replicates intensively in the cytoplasm of myocardiocytes and the acute myocarditis is strictly related to the tropism of these cells. Four pigs died spontaneously. In three animals no post mortem lesions or virus were isolated/detected, although all of them showed mild myocarditis. The experimental infection with EMCV B279/95 indicates: (i) the experimental protocol mimics the individual variability observed in natural disease, (ii) tonsils are the portal of entry of infection and the heart is the target organ, (iii) EMCV provides a valuable animal model for comparative studies on progressive viral myocarditis.  相似文献   
126.
Proliferative orf virus infections in adult sheep have increased in Italy in the past few years: these extreme cases are frequently fatal and difficult to differentiate from other infectious diseases of sheep such as blue tongue. A probable explanation for the proliferative and highly vascularized nature of the lesions was found in the expression of the VEGF-E gene encoded by the orf virus. To investigate a possible role of the viral VEGF in the pathogenesis of severe persistent orf virus lesions, the activity of four VEGF-E variants was compared by an angiogenesis in vitro model. Similar angiogenic activity was found between strains isolated from the classical and the proliferative forms of the disease, even if the latter was able to develop a higher number of vessels during the first 24 h of infection. Our in vitro findings seems to exclude that the VEGF variants encoded by the strain isolated from the atypical form of the disease could be the responsible for the histopathological aspect of the proliferative lesions.  相似文献   
127.
Herbicides are released to the environment with potential ecotoxicological risks for mammals. Yeast is a good model to elucidate toxicity mechanisms. We investigated how three commercial herbicides (Proper Energy, Pointer, and Silglif) and their active ingredients (respectively, fenoxaprop-P-ethyl, tribenuron methyl, and glyphosate) can affect biological activities of an oenological Saccharomyces cerevisiae strain, which may be resident on grape vineyards of the same geographical areas where herbicides are used. The use of commercial grade herbicides employed in Italy allowed us to reproduce the same conditions applied in crops; at the same time, assaying pure single active compounds made it possible to compare the effects obtained with commercial formulations. Interestingly, we found that while pure active compounds affect cell growth and metabolism at a lower extent, commercial preparations have a significant major negative influence on yeast biology.  相似文献   
128.
Ten genotypes belonging to Lactuca sativa, Cicorium intybus, Plantago coronopus, Eruca sativa, and Diplotaxis tenuifolia and used in fresh mixed salads were investigated for their polyphenol contents. Flavonoids and hydroxycinnamic acids were characterized by high-performance liquid chromatography (HPLC)/diode array detection/mass spectrometry. Quercetin, kaempferol, luteolin, apigenin, and crysoeriol derivatives were identified; hydroxycinnamic acids were all caffeoyl derivatives. The total polyphenol content was obtained through the Folin-Ciocalteu test and from the HPLC data. The amounts ranged between 0.9 and 4.7 mg/g fresh weight. The antiradical activity was determined by the reaction with the stable DPPH* radical. The Fe2+ chelating activity was determined with a spectrophotometric test. From the complex of data, a quite complete picture of the characteristics of the vegetables emerges. A cultivated C. intybus cultivar exhibited the highest polyphenol content, while a wild C. intybus genotype exhibited the highest antiradical activity. In every case, the characteristics of the different salads as functional foods have been pointed out.  相似文献   
129.
We characterized "Olivastra Seggianese" extra virgin olive oil (EVOO) and evaluated its chemical and sensory characteristics and antioxidant and antiradical activities during storage under novel conditions. Two oils (A and B) were analyzed for the commodity characteristics at blending (t0) and after 9, 12, and 18 months; panel tests were performed and minor polar compounds (MPC) content was assessed at blending (t0) and after 6, 9, 12, and 18 months. Antioxidant and antiradical activities in vitro were evaluated at t0 and after 12 months, by human low density lipoprotein (LDL) and 1,1-diphenyl-2-picrylhydrazil radical (DPPH*) tests. Oil A, which had an initially higher MPC content, possessed "harder" organoleptic characteristics than oil B, which had a lower MPC content and was endowed with a "smoother" taste profile. Statistical analyses showed that secoiridoids, particularly deacetoxy-oleuropein aglycone, should be quantified to evaluate EVOO stability during storage. The antioxidant activity toward human LDL was linked to MPC content and to storage time. The tests on the stable free radical DPPH* confirmed the results on human LDL. We propose this as an additional parameter to evaluate olive oil quality and stability over time.  相似文献   
130.
The susceptibility to trypsin of conglutin gamma, a lupin seed glycoprotein affected by this enzyme only when in a non-native conformation, was used to study the effect of Zn(2+) and other metal ions on the structural dynamics of the protein. When acid-treated trypsin-susceptible conglutin gamma was incubated at neutral pH in the presence of Zn(2+), it became resistant to tryptic attack, contrary to the protein treated in the absence of Zn(2+). The time course of this refolding event has been quantitatively evaluated by SDS-PAGE. Amino acid sequencing of the major polypeptide fragments, produced by trypsin before completion of the refolding process, indicated that only a few cleavable bonds were accessible to the enzyme. This suggested that the presence of metal ions affected the pathway of degradation of the protein, by inducing its folding. Among the other metal ions tested, Ni(2+) also promoted the adoption of a trypsin-resistant conformation of conglutin gamma, whereas Mn(2+) and Ca(2+) had only much lower effects. The relevance of these findings for a deeper understanding of the in vivo degradation of plant food proteins and how it is affected by metal ions are discussed.  相似文献   
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