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1.
Aurora Romero Tejeda Roberta Aiello Angela Salomoni Valeria Berton Marta Vascellari Giovanni Cattoli 《Veterinary research》2015,46(1)
The study of influenza type A (IA) infections in wild mammals populations is a critical gap in our knowledge of how IA viruses evolve in novel hosts that could be in close contact with avian reservoir species and other wild animals. The aim of this study was to evaluate the susceptibility to infection, the nasal shedding and the transmissibility of the H7N1 and H5N1 highly pathogenic avian influenza (HPAI) viruses in the bank vole (Myodes glareolus), a wild rodent common throughout Europe and Asia. Two out of 24 H5N1-infected voles displayed evident respiratory distress, while H7N1-infected voles remained asymptomatic. Viable virus was isolated from nasal washes collected from animals infected with both HPAI viruses, and extra-pulmonary infection was confirmed in both experimental groups. Histopathological lesions were evident in the respiratory tract of infected animals, although immunohistochemistry positivity was only detected in lungs and trachea of two H7N1-infected voles. Both HPAI viruses were transmitted by direct contact, and seroconversion was confirmed in 50% and 12.5% of the asymptomatic sentinels in the H7N1 and H5N1 groups, respectively. Interestingly, viable virus was isolated from lungs and nasal washes collected from contact sentinels of both groups. The present study demonstrated that two non-rodent adapted HPAI viruses caused asymptomatic infection in bank voles, which shed high amounts of the viruses and were able to infect contact voles. Further investigations are needed to determine whether bank voles could be involved as silent hosts in the transmission of HPAI viruses to other mammals and domestic poultry. 相似文献
2.
Catia Pereira Itziar Aurora Montalbán Olatz García-Mendiguren Tomás Goicoa Maria Dolores Ugarte Sandra Correia Jorge Manuel Canhoto Paloma Moncaleán 《Journal of Forest Research》2016,21(3):143-150
Pinus halepensis has been described as a drought-tolerant species with high plasticity to growth in different environments. Its eco-physiological characteristics could facilitate the use of this species in large afforestations in the future scenery of climate change. Somatic embryogenesis is a biotechnological tool with potential for large-scale clonal propagation. In order to establish an improved regeneration protocol for Pinus halepensis, the effects of different temperatures (18, 23, and 28 °C) and water availability conditions (2, 3, and 4 g L?1 Gelrite®), during initiation of embryonal masses on the rate of initiation, proliferation, maturation, and the number of embryos developed, were evaluated. It was found that environmental conditions during the initiation stage of Pinus halepensis somatic embryogenesis influence the success of initiation and proliferation. In contrast, there was no effect of these conditions on the maturation rates and the number of somatic embryos. Somatic embryos were obtained in all treatments tested, indicating that plants can be produced from extreme conditions of induction, such as high temperatures (28 °C) and low water availability conditions (4 g L?1). 相似文献
3.
Napolitano A Fogliano V Tafuri A Ritieni A 《Journal of agricultural and food chemistry》2007,55(25):10499-10504
Ochratoxin A is an important mycotoxin that can enter the human food chain in cereals, wine, coffee, spices, beer, cocoa, dried fruits, and pork meats. Coffee is one of the most common beverages and, consequently, it has a potential risk factor for human health related to ochratoxin A exposure. In this study, coffee and corresponding byproducts from seven different geographic regions were investigated for ochratoxin A natural occurrence by HPLC-FLD, nutritional characterization, and antioxidant activities by spectrophotometric assay. The research focused on composition changes in coffee during the processing step "from field to cup". Costa Rica and Indian green coffees were the most contaminated samples, with 13 and 11 microg/kg, respectively, while the Ethiopian coffee was the least contaminated, with 3.8 microg/kg of ochratoxin A. The reduction of ochratoxin A contamination during the roasting step was comparable for any samples that were considered under the recommended level of 4 microg/kg. Total dietary fibers ranged from 58.7% for Vietnam and 48.6% for Ivory Coast in green coffees and ranged from 58.6% for Costa Rica to 61.2% for India in roasted coffee. Coffee silverskin byproduct obtained from Ivory Coast was the highest, with 69.2 and 64.2% of insoluble dietary fibers, respectively. 相似文献
4.
Touriño S Selga A Jiménez A Juliá L Lozano C Lizárraga D Cascante M Torres JL 《Journal of agricultural and food chemistry》2005,53(12):4728-4735
Pine (Pinus pinaster) bark is a rich source of procyanidin oligomers. From a total polyphenolic extract, we have generated fractions of different procyanidin composition. The mixtures, devoid of gallate esters, were active as free radical scavengers against ABTS(*+), DPPH, and HNTTM. Pine bark fractions were tested for antioxidant activity in solution (hydrogen donation and electron transfer) and emulsion (inhibition of lipid peroxidation) and compared with their galloylated counterparts from grape origin. While galloylation clearly influenced the free radical scavenging efficiency in solution, it did not seem to play a determinant role in protection against lipid peroxidation in emulsion. The fractions were very mild inhibitors of cell proliferation. Because gallate esters appear to interfere with crucial cell functions, gallate free pine procyanidins may be the innocuous chemopreventative agents of choice for many applications in food and skin protection. 相似文献
5.
Napolitano A Lanzuise S Ruocco M Arlotti G Ranieri R Knutsen SH Lorito M Fogliano V 《Journal of agricultural and food chemistry》2006,54(20):7863-7869
Nutritionists recommend increasing the intake of soluble dietary fiber (SDF), which is very low in most cereal-based products. Conversion of insoluble DF (IDF) into SDF can be achieved by chemical treatments, but this affects the sensorial properties of the products. In this study, the possibility of getting a substantial increase of SDF from cereal products using a tailored preparation of Trichoderma enzymes is reported. Enzymes were produced cultivating Trichoderma using durum wheat fiber (DWF) and barley spent grain (BSG) as unique carbon sources. Many Trichoderma strains were screened, and the hydrolysis conditions able to increase by enzymatic treatment the amount of SDF in DWF and BSG were determined. Results demonstrate in both products that it is possible to triple the amount of SDF without a marked decrease of total DF. The enzymatic treatment also causes the release of hydroxycinnamic acids, mainly ferulic acid, that are linked to the polysaccharides chains. This increases the free phenolic concentration, the water-soluble antioxidant activity, and, in turn, the phenol compounds bioavailability. 相似文献
6.
Joaquin Gutiérrez Hugo Travieso M. Aurora Pubillones 《Water, air, and soil pollution》1993,68(3-4):315-323
A method has been developed that uses a mixed solution of NaOH, NaCl and cysteine to digest fish. Inorganic Hg and MgHg were determined by cold vapor atomic absorption (CVAAS) using a selective reduction step with SnCl2 and SnCL2-solutions. Ethyl alcohol was satisfactorily used to prevent excessive foaming. Two optimum digestion procedures were established: (1) using a dry block heater at 90 °C for 1 hr and (2) overnight digestion at 25 to 30 °C. Differences between both were not significant (95%) in the range of 30 to 500 ng g?1 Hg (II) and MeHg in fish. Reduction of the Hg signal due to matrix effects in different fish species was evaluated (95 to 60%). Oily fish, shrimp and lobsters gave the highest reduction. Internal calibration by addition of Hg standards are strongly recommended when exact determinations are needed. The detection limit obtained was near 10 ng g?1. Signals were linear in the concentration range studied (30 to 500 ng g?1). Accuracy of analyses was in the order of 5% or better, with a relative standard deviation of 5%. The method could be applied to other environmental matrices: hair, urine and blood, with some modifications. 相似文献
7.
M. Elena Gorman Aurora Villarroel Susan J. Tornquist Joy Flachsbart Annette Warden Lisa Boeder 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(3):388-391
Background: Analysis of body fluids includes an estimate of total nucleated cell count (TNCC). Automated methods may enhance the accuracy and timeliness of TNCC results. Objective: The purpose of this report was to assess the ability of the ADVIA 120 hematology analyzer to accurately count nucleated cells in pleural and peritoneal fluids from animals, compared with manual counts. Methods: Pleural and peritoneal fluids submitted in EDTA tubes to our laboratory over a 17‐month period were used in the study. TNCC/μL was determined by a manual method, using a hemocytometer, and by an automated method, using the ADVIA 120. Correlation of results was determined by Passing‐Bablok regression, Bland–Altman plots, and Pearson correlation analysis. Results: Samples from dogs (n=36), cats (n=36), horses (n=59), and alpacas (n=11) were analyzed. High correlation in TNCC between methods was found for peritoneal fluid (n=93, r=.959), pleural fluid (n=49, r=.966), and all fluids combined (n=142, r=.960) (P<.001). Variation between methods was greater in samples with TNCCs<1000/μL (r=.62, P<.001). The ADVIA systematically overestimated the number of cells in all fluid samples by 95 cells/μL (confidence interval=19.2–190.5/μL). Conclusion: The ADVIA 120 reliably determines TNCC in pleural and peritoneal effusions and can be recommended for routine veterinary laboratory analysis. 相似文献
8.
The odor-active compounds of dry-fermented sausages with added nitrite or nitrate as curing agents were identified by gas chromatography-olfactometry (GC-O) applying the detection frequency (DF) method. The quantification of these compounds in the sausage was determined by multiple headspace solid-phase microextraction (multiple HS-SPME). There were no specific odor-active compounds related to the use of nitrite or nitrate although there were differences in the DF value of several compounds. The nitrite-added sausages presented higher DF values for ethanol, 1-hexanol, propanoic acid, 2-heptenal, and nonanal while the nitrate-added sausages had higher DF values for phenylacetaldehyde and 3-methyl-butanal. Eighteen compounds were quantified by multiple HS-SPME. Most of them were above their air detection thresholds, but only hexanal, heptanal, and 1-octen-3-ol were in a concentration higher than their oil threshold values. These compounds would probably be the main contributors to the aroma of fermented sausages. 相似文献
9.
Napolitano A Morales F Sacchi R Fogliano V 《Journal of agricultural and food chemistry》2008,56(6):2034-2040
In this paper the relationship between virgin olive oil (VOO) phenol compounds and the formation of acrylamide in potato crisps was investigated. The phenol compositions of 20 VOO samples were screened by LC-MS, and 4 oils, characterized by different phenol compound patterns, were selected for frying experiments. Slices of potatoes were fried at 180 degrees C for 5, 10, and 15 min, and acrylamide content was determined by LC-MS. Results demonstrated that VOO phenolic compounds are not degraded during frying, and crisp color was not significantly different among the four VOOs. Acrylamide concentration in crisps increased during frying time, but the formation was faster in the oil having the lowest concentration of phenolic compounds. Moreover, the VOO having the highest concentration of ortho-diphenolic compounds is able to efficiently inhibit acrylamide formation in crisps from mild to moderate frying conditions. It was concluded that the use of ortho-diphenolic-rich VOOs can be proposed as a reliable mitigation strategy to reduce acrylamide formation in domestic deep-frying. 相似文献
10.
Esperanza Álvarez Aurora Romar María Luisa Fernández-Marcos 《Journal of Soils and Sediments》2013,13(1):72-81