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11.
When the mare’s estrous cycle resumes in winter, the β-carotene content of hay is depleted. Sixty Italian trotter mares were randomly assigned to a Control or a Treated Group. Treated Group received 1g/d synthetic β-carotene for 15 days from parturition. Blood samples collected at parturition and on days 5, 10 and 15 after partum were analysed for β-carotene, vitamins A, progesterone, 17 β-estradiol, the energy parameters (glucose, cholesterol, NEFA), the protein profile (total protein, albumin, urea) and LDH. Some changes in these measures were attributable to treatment, which significantly affected β-carotene and 17 β-estradiol concentrations. A significant effect was also found on the resumption of estrous activity (χ2 test=P<0.052).  相似文献   
12.
Olive fruits are seriously deteriorated by pre and postharvest damage due to the attack of insects, such as Bactrocera olaea, which strongly alters the quality of olives. Defence response in olive fruits injured both by pathogens and by mechanical damages has been associated with the enzyme β-glucosidase, which specifically hydrolyses oleuropein, producing highly reactive aldehyde molecules. In situ detection of ~-glucosidase activity in olive fruit tissues following injury, which simulates Bactrocera oleae punctures, is reported. The assay was performed in two cultivars showing different degrees of susceptibilities to fly infestation. In both cultivars, the histochemical assay for β-glucosidase showed that within 20 min after the injury, a strong ~-glucosidase activity could be observed in the damaged tissues. Thereafter a progressive enzyme inactivation occurred starting from tissues around the boundary of the injury with decrease of the enzyme activity and stopped after 3 h. Whereas the mass of active cells reached a distance of (300±50) μm from the edge of the injury. Biochemical analyses showed that in extracts of the injured fruit, β-glucosidase activity rapidly increased within 20 min from injury, thereafter decreasing and reaching values comparable with those in intact fruits. Following puncture, the oleuropein contents did not change significantly in the high susceptibility cultivar, whereas it rapidly decreased in the cultivar showing low susceptibility. The results strongly suggest that olive fruits susceptible towards fly infestation could be related to the ability of the oleuropein-degrading-β-glucosidase to produce the highly reactive molecules in the damaged tissues. As a consequence of puncture, high level of peroxidase activity was detected. This feature also suggested that this enzyme could play a key role in the defence response against insect injuries.  相似文献   
13.
Olive fruits are seriously deteriorated by pre and postharvest damage due to the attack of insects, such as Bactrocera olaea, which strongly alters the quality of olives. Defence response in olive fruits injured both by pathogens and by mechanical damages has been associated with the enzyme β-glucosidase, which specifically hydrolyses oleuropein, producing highly reactive aldehyde molecules. In situ detection of β-glucosidase activity in olive fruit tissues following injury, which simulates Bactrocera oleae punctures, is reported. The assay was performed in two cultivars showing different degrees of susceptibilities to fly infestation. In both cultivars, the histochemical assay for β-glucosidase showed that within 20 min after the injury, a strong β-glucosidase activity could be observed in the damaged tissues. Thereafter a progressive enzyme inactivation occurred starting from tissues around the boundary of the injury with decrease of the enzyme activity and stopped after 3h. Whereas the mass of active celsreached a distance of (300±50)μm from the edge of the injury. Biochemical analyses showed that in extracts of the injured fruit, β-glucosidase activity rapidly increased within 20 min from injury, thereafter decreasing and reaching values comparable with those in intact fruits. Following puncture, the oleuropein contents did not change significantly in the high susceptibility cultivar, whereas it rapidly decreased in the cultivar showing low susceptibility. The results strongly suggest that olive fruits susceptible towards fly infestation could be related to the ability of the oleuropein-degrading-β-glucosidase to produce the highly reactive molecules in the damaged tissues. As a consequence of puncture, high level of peroxidase activity was detected. This feature also suggested that this enzyme could play a key role in the defence response against insect injuries.  相似文献   
14.
15.
Espen L  Cocucci M  Sacchi GA 《Tree physiology》2005,25(11):1419-1425
Micrografts of internodes excised from in vitro grown pear plants (Pyrus communis L. cv. 'Bosc' (B) and cv. 'Butirra Hardy' (BH)) and quince (Cydonia oblonga Mill. East Malling clone C (EMC)), were cultured aseptically to test the effectiveness of their functional vascular reconnection in relation to incompatibility-compatibility relationships that these genotypes exhibit in the field. The incompatible heterograft (B/EMC) showed a marked delay in internode cohesion compared with the autografts (both B/B and BH/BH) and the compatible heterograft (BH/EMC). Even when fused, the translocation of [14C]-sorbitol from upper to lower internode was lower in B/EMC micrografts than in the other combinations. Epifluorescence studies performed with carboxyfluorescin, a specific phloem probe, indicated that the limited translocation was caused by a delay in the establishment of functional phloem continuity between the two internodes. In the B/EMC combination, new differentiated tracheary elements (TE) in the parenchyma tissue at the graft interface between the two internodes were not detected until 30 days after grafting, whereas in the BH/EMC heterograft and both autografts, new xylem connections appeared to cross the interface 20 days after grafting. Immunohistochemical detection (terminal nick-end labeling assay) of the number of cells undergoing nuclear DNA fragmentation at the graft interface confirmed that the limited and delayed TE differentiation in B/EMC heterografts was associated with a decrease in the activity of programmed cell death processes involved in the differentiation of TE.  相似文献   
16.
Polyphenolic grapevine components involved in plant resistance against pathogens possess various pharmacological properties that include nitric oxide (NO)-dependent vasodilation and anti-inflammatory and free radical scavenging activities, which may explain the protective effect of moderate red wine consumption against cardiovascular disease. The aim of this work was (a) to verify the possibility that preharvest treatments of grapevine with a plant activator, benzo-(1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH), could lead to an enriched nutraceutical potential of wine and (b) to characterize the profile of metabolites responsible for pharmacological activity. Plant spraying at the end of veraison, with a water suspension of BTH (0.3 mM), led to increased whole anthocyanin content as confirmed by HPLC comparative analysis. Extracts from berry skins of BTH-treated grapevines caused NO-dependent vasorelaxation, with a concentration-response curve that was significantly shifted to the left of the control non-BTH-treated curve. Moreover, 1:1000 dilutions of berry extracts from BTH-treated plants significantly increased basal production of guanosine 3',5'-cyclic monophosphate (cGMP) in human vascular endothelial cells when compared to the corresponding extracts of untreated plants. These results show that BTH treatment increases anthocyanin content of grape extracts, as well as their ability to induce NO-mediated vasoprotection. No increase of anthocyanin content was observed in the wine extracts from BTH-treated vines. It is concluded that BTH treatment could be exploited to increase the nutraceutical potential of grapes.  相似文献   
17.
The citrus-processing industry generates in the Mediterranean area huge amounts of orange peel as a byproduct from the industrial extraction of citrus juices. To reduce its environmental impact as well as to provide an extra profit, this residue was investigated in this study as an alternative substrate for the fermentative production of citric acid. Orange peel contained 16.9% soluble sugars, 9.21% cellulose, 10.5% hemicellulose, and 42.5% pectin as the most important components. To get solutions rich in soluble and starchy sugars to be used as a carbon source for citric acid fermentation, this raw material was submitted to autohydrolysis, a process that does not make use of any acidic catalyst. Liquors obtained by this process under optimum conditions (temperature of 130 degrees C and a liquid/solid ratio of 8.0 g/g) contained 38.2 g/L free sugars (8.3 g/L sucrose, 13.7 g/L glucose, and 16.2 g/L fructose) and significant amounts of metals, particularly Mg, Ca, Zn, and K. Without additional nutrients, these liquors were employed for citric acid production by Aspergillus niger CECT 2090 (ATCC 9142, NRRL 599). Addition of calcium carbonate enhanced citric acid production because it prevented progressive acidification of the medium. Moreover, the influence of methanol addition on citric acid formation was investigated. Under the best conditions (40 mL of methanol/kg of medium), an effective conversion of sugars into citric acid was ensured (maximum citric acid concentration of 9.2 g/L, volumetric productivity of 0.128 g/(L.h), and yield of product on consumed sugars of 0.53 g/g), hence demonstrating the potential of orange peel wastes as an alternative raw material for citric acid fermentation.  相似文献   
18.
Contagious bovine pleuropneumonia (CBPP), caused by Mycoplasma mycoides subsp. mycoides (Mmm) is a severe cattle disease, present in many countries in sub-Saharan Africa. The development of improved diagnostic tests and vaccines for CBPP control remains a research priority. Polyacrylamide gel electrophoresis and mass spectrometry were used to characterize the Triton X-114 soluble proteome of nine Mmm strains isolated from Europe or Africa. Of a total of 250 proteins detected, 67 were present in all strains investigated. Of these, 44 were predicted to be lipoproteins or cytoplasmic membrane-associated proteins and are thus likely to be members of the core in vitro surface membrane-associated proteome of Mmm. Moreover, the presence of all identified proteins in other ruminant Mycoplasma pathogens were investigated. Two proteins of the core proteome were identified only in other cattle pathogens of the genus Mycoplasma pointing towards a role in host–pathogen interactions. The data generated will facilitate the identification and prioritization of candidate Mycoplasma antigens for improved control measures, as it is likely that surface-exposed membrane proteins will include those that are involved in host–pathogen interactions.  相似文献   
19.
The color features and the evolution of both the monomeric and the derived pigments of red wines aged in oak and cherry 225 L barriques have been investigated during a four months period. For cherry wood, the utilization of 1000 L casks was tested as well. The use of cherry casks resulted in a faster evolution of pigments with a rapid decline of monomeric anthocyanins and a quick augmentation formation of derived and polymeric compounds. At the end of the aging, wines stored in oak and cherry barriques lost, respectively, about 20% and 80% of the initial pigment amount, while in the 1000 L cherry casks, the same compounds diminished by about 60%. Ethyl-bridged adducts and vitisins were the main class of derivatives formed, representing up to 25% of the total pigment amount in the cherry aged samples. Color density augmented in both the oak and cherry wood aged samples, but the latter had the highest values of this parameter. Because of the highly oxidative behavior of the cherry barriques, the use of larger casks (e.g., 1000 L) is proposed in the case of prolonged aging times.  相似文献   
20.
In this case report from Italy we describe a fatal infection caused by A. hydrophila in a 39 yr old cirrhotic patient. This pathogen was isolated as a pure single culture from the patient's blood sample. The patient died on the second day of hospitalization from overwhelming sepsis. The A. hydrophila isolate was tested for different potential virulence properties, such as invasiveness, adherence, exotoxins production, presence of fimbriae and for the patterns of resistance to a variety of antimicrobial agents. Although, the Aeromonas species are infrequently reported as a cause of human infections, the present case study confirms the capability of these pathogens to induce serious human infections.  相似文献   
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