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101.
Paltrinieri S Metzger C Battilani M Pocacqua V Gelain ME Giordano A 《Journal of Feline Medicine and Surgery》2007,9(4):271-277
Previous studies have demonstrated that the concentration of alpha1-acid glycoprotein (AGP) transiently increases in asymptomatic cats infected with feline coronavirus (FCoV). In order to establish whether these fluctuations depend on the FCoV status, the serum concentration of AGP and anti-FCoV antibody titres and/or faecal shedding of FCoVs in clinically healthy cats from catteries with different levels of prevalence of FCoV infection were monitored over time. Serum AGP concentrations fluctuated over time in clinically healthy cats from the cattery with the highest prevalence of feline infectious peritonitis (FIP) and significantly increased just before an outbreak of FIP. Further studies are required to clarify whether the observed increase of AGP concentration is a consequence of the increased viral burden or a protective response against mutated viral strains. Nevertheless, the results of the present study suggest that AGP might be useful in monitoring FCoV-host interactions in FCoV-endemic catteries. 相似文献
102.
103.
Mara B. Depetris Carlos A. Acuña Susana Gutierrez Florencia Marcón Silvina A. Felitti 《Grass and Forage Science》2020,75(3):316-325
In natural ecosystems, plants appear to be in symbiosis with diverse fungal endophytes which can have impacts on plant communities. Paspalum is one of the most important grass genera in South American grasslands. The aim of this work was to determine the presence of fungal endophytes in two Paspalum species and evaluate their effects on plant growth. Sixty plant samples were collected for Paspalum notatum in a rangeland in northeastern Argentina, and the same number for Paspalum dilatatum in central Argentina. A triple-sterilization process was carried out by submerging small pieces of leaves and stems for the isolation of fungi from the collected plants. In order to identify endophytes, morphological characters and fungal sequences corresponding to the ITS (Internal Transcribed Spacer) region were analysed. A total of eight genera were identified: Acremonium, Alternaria, Aspergillus, Bipolaris, Cladosporium, Fusarium, Penicillium and Trichoderma. A greenhouse trial was conducted to determine the effects of fungal endophytes on growth. Trichoderma significantly increased relative chlorophyll content in P. notatum and Acremonium endophytes increased tiller number, and above- and below-ground biomass in P. dilatatum. The diversity of fungal endophytes that was present in P. notatum and P. dilatatum was described. In conclusion, some aspects of growth of these Paspalum species seem to be positively affected by Trichoderma and Acremonium. 相似文献
104.
We reported earlier that somaclonal variant HS (HS), regenerated from Prunus avium `Hedelfinger’ (H) leaf explants, showed reduced apical dominance both in vitro and in vivo. In this report we found that
the somaclone HS, showed reduced vegetative vigour as determined by trunk circumference and tree height nevertheless natural
architecture of the tree was preserved. HS canopy was less crowded as to compare to H and leaves were shorter with a shorter
petiole, they were better spaced out as indicated by internodes length. HS had a significantly thinner cuticle and wax layer
compared to H leaves surface. Histological analysis of leaves also showed that HS had thicker mesophyll and palisade the latter
composed of more than one layer which, together with increased stomatal density, are distinguishing signs of extensive exposure
of leaves to sun. Chlorophyll a and chlorophyll b content did not differ between H and HS, β-carotene content was slightly
lower in HS leaves. However no significant differences were found between the two genotypes in terms of net photosynthesis,
intercellular CO2 concentration, leaf transpiration and water use efficiency. HS flowered 1-year later than H and number of flowers was reduced.
Fruit size, shape, skin colour change during the ripening process and the main parameters of fruit quality as assessed in
the wild type and the somaclone were basically the same. 相似文献
105.
Olga Rubilar Gonzalo R. Tortella Raphael Cuevas Mara Cea Susana Rodríguez-Couto María Cristina Diez 《Water, air, and soil pollution》2012,223(5):2463-2472
This study investigates pentachlorophenol (PCP) adsorption by the white-rot fungus Anthracophyllum discolor in a fixed-bed column reactor. PCP adsorption at different concentrations (20, 30, and 50?mg?L?1) and pH values (5.0, 5.5, and 6.0) was determined and modeled using the Thomas model. Fourier transform infrared spectroscopy (FTIR) was used to identify functional groups of biomass that may participate in the interaction of PCP. The biosorption capacity of A. discolor was pH-dependent, and the PCP adsorbed increased with the decrease in the pH solution. Acid pH values of the influent gave an increase in saturation time in all PCP concentrations. By contrast, the increase in PCP concentration caused that the binding sites were filled quickly, resulting in a decrease in saturation time. The Thomas model was found suitable for describing the entire dynamic of the column with respect to the PCP concentration and pH of the solution. FTIR results showed that amines, carboxylates, alkanes, and C?CO groups might participate in the PCP adsorption on the biomass surface. It was concluded that A. discolor biomass was a good adsorbent for PCP removal from influent with mainly acidic pH. 相似文献
106.
María T. Domínguez Teodoro Marañón José M. Murillo Rainer Schulin Brett H. Robinson 《Water, air, and soil pollution》2010,205(1-4):305-321
Soil contamination may contribute to forest decline, by altering nutrient cycling and acquisition by plants. This may hamper the establishment of a woody plant cover in contaminated areas, thus limiting the success of a restoration program. We studied the nutritional status of planted saplings of Holm oak (Quercus ilex subsp. ballota (Desf.) Samp.), white poplar (Populus alba L.), and wild olive tree (Olea europaea var. sylvestris Brot.) in the Guadiamar Green Corridor (SW Spain) and compared it with established adult trees. Soils in this area were affected by a mine-spill in 1998 and a subsequent restoration program. The spill resulted in soil acidification, due to pyrite oxidation, and deposited high concentrations of some trace elements. In some sites, we detected a phosphorus deficiency in the leaves of Q. ilex and O. europaea saplings, as indicated by a high N:P ratio (>16). For O. europaea, soil contamination explained 40% of the variability in leaf P and was negatively related to chlorophyll content. Soil pH was a significant factor predicting the variability of several nutrients, including Mg, P, and S. The uptake of Mg and S by P. alba was greater in acidic soils. The monitoring of soil pH is recommended since long-term effects of soil acidification may negatively affect the nutritional status of the trees. 相似文献
107.
108.
Katrine M. Paulsen Carlos G. das Neves Erik G. Granquist Knut Madslien Snorre Stuen Benedikte N. Pedersen Rose Vikse Mara Rocchi Ellie Laming Karin Stiasny shild K. Andreassen 《Zoonoses and public health》2020,67(4):342-351
Tick‐borne encephalitis virus (TBEV) is the causative agent of tick‐borne encephalitis (TBE). TBEV is one of the most important neurological pathogens transmitted by tick bites in Europe. The objectives of this study were to investigate the seroprevalence of TBE antibodies in cervids in Norway and the possible emergence of new foci, and furthermore to evaluate if cervids can function as sentinel animals for the distribution of TBEV in the country. Serum samples from 286 moose, 148 roe deer, 140 red deer and 83 reindeer from all over Norway were collected and screened for TBE immunoglobulin G (IgG) antibodies with a modified commercial enzyme‐linked immunosorbent assay (ELISA) and confirmed by TBEV serum neutralisation test (SNT). The overall seroprevalence against the TBEV complex in the cervid specimens from Norway was 4.6%. The highest number of seropositive cervids was found in south‐eastern Norway, but seropositive cervids were also detected in southern‐ and central Norway. Antibodies against TBEV detected by SNT were present in 9.4% of the moose samples, 1.4% in red deer, 0.7% in roe deer, and nil in reindeer. The majority of the positive samples in our study originated from areas where human cases of TBE have been reported in Norway. The study is the first comprehensive screening of cervid species in Norway for antibodies to TBEV, and shows that cervids are useful sentinel animals to indicate TBEV occurrence, as supplement to studies in ticks. Furthermore, the results indicate that TBEV might be spreading northwards in Norway. This information may be of relevance for public health considerations and supports previous findings of TBEV in ticks in Norway. 相似文献
109.
Orozco MI Priego-Capote F Luque de Castro MD 《Journal of agricultural and food chemistry》2011,59(13):7194-7202
The influence of deep frying, mimicked by 20 heating cycles at 180 °C (each cycle from ambient temperature to 180 °C maintained for 5 min), on the unsaponifiable fraction of vegetable edible oils represented by three characteristic families of compounds (namely, phytosterols, aliphatic alcohols, and triterpenic compounds) has been studied. The target oils were extra virgin olive oil (with intrinsic content of phenolic antioxidants), refined sunflower oil enriched with antioxidant phenolic compounds isolated from olive pomace, refined sunflower oil enriched with an autoxidation inhibitor (dimethylpolysiloxane), and refined sunflower oil without enrichment. Monitoring of the target analytes as a function of both heating cycle and the presence of natural antioxidants was also evaluated by comparison of the profiles after each heating cycle. Identification and quantitation of the target compounds were performed by gas cromatography-mass spectrometry in single ion monitoring mode. Analysis of the heated oils revealed that the addition of natural antioxidants could be an excellent strategy to decrease degradation of lipidic components of the unsaponifiable fraction with the consequent improvement of stability. 相似文献
110.
Battilani M Balboni A Ustulin M Giunti M Scagliarini A Prosperi S 《Veterinary research》2011,42(1):43
ABSTRACT: Parvoviruses of carnivores include three closely related autonomous parvoviruses: canine parvovirus (CPV), feline panleukopenia virus (FPV) and mink enteritis virus (MEV). These viruses cause a variety of serious diseases, especially in young patients, since they have a remarkable predilection for replication in rapidly dividing cells. FPV is not the only parvovirus species which infects cats; in addition to MEV, the new variants of canine parvovirus, CPV-2a, 2b and 2c have also penetrated the feline host-range, and they are able to infect and replicate in cats, causing diseases indistinguishable from feline panleukopenia. Furthermore, as cats are susceptible to both CPV-2 and FPV viruses, superinfection and co-infection with multiple parvovirus strains may occur, potentially facilitating recombination and high genetic heterogeneity. In the light of the importance of cats as a potential source of genetic diversity for parvoviruses and, since feline panleukopenia virus has re-emerged as a major cause of mortality in felines, the present study has explored the molecular characteristics of parvovirus strains circulating in cat populations. The most significant findings reported in this study were (a) the detection of mixed infection FPV/CPV with the presence of one parvovirus variant which is a true intermediate between FPV/CPV and (b) the quasispecies cloud size of one CPV sample variant 2c. In conclusion, this study provides new important results about the evolutionary dynamics of CPV infections in cats, showing that CPV has presumably started a new process of readaptation in feline hosts. 相似文献