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231.
Donati M Laroucau K Storni E Mazzeo C Magnino S Di Francesco A Baldelli R Ceglie L Renzi M Cevenini R 《Veterinary microbiology》2009,135(1-2):181-185
Specific antibodies to plasmid-encoded protein pgp3 are known to be encountered in human Chlamydia (C.) trachomatis infections. In order to verify whether antibodies to this protein could be developed in animals infected with plasmid-carrying chlamydial strains, 454 animal sera were examined using a home-made pgp3 protein ELISA and Western blots (WB) of recombinant pgp3 protein from Chlamydophila (Cp.) psittaci. Likewise, 50 human sera were tested by ELISA and WB of recombinant pgp3 from C. trachomatis. The reactivity against pgp3 protein was compared to the reactivity against chlamydial elementary bodies (EBs) detected by microimmunofluorescence (MIF) test. The presence of pgp3-specific antibodies was demonstrated in most ducks and pigeons with Cp. psittaci infection detected by MIF, as well as in the majority of symptomatic cats and pigs infected with Cp. felis and C. suis, respectively, which reacted at high titres to Cp. felis and C. suis EBs by MIF. Moreover, most of the sera collected from patients with C. trachomatis culture-confirmed infection and seropositive to C. trachomatis by MIF, presented antibodies specific to C. trachomatis pgp3 recombinant protein. Therefore, pgp3 protein could be a useful marker of chlamydial infections in animals, as well as in humans. 相似文献
232.
Gutierrez-Bañuelos H Anderson RC Carstens GE Tedeschi LO Pinchak WE Cabrera-Diaz E Krueger NA Callaway TR Nisbet DJ 《Journal of agricultural and food chemistry》2008,56(12):4650-4658
Nitroethane is a potent inhibitor of ruminal CH 4 production, a digestive inefficiency resulting in the loss of 2-15% of a ruminant's gross energy intake and an important emission source of this greenhouse gas. To assess the effect of nitroethane on methanogenesis and characterize ruminal adaptation observed with low treatment doses to this inhibitor, ruminal microbes were cultured in vitro with supplements of water (controls), 4.5 and 9 mM nitroethane, and 0.09 mM monensin, with or without 9 mM nitroethane. All treatments decreased CH 4 production >78% compared to controls; however, differential effects of treatments were observed on CO 2, butyrate isobutyrate, and valerate production. Treatments did not affect H 2 accumulation or acetate and propionate production. Most probable numbers of nitrometabolizing bacteria were increased with 4.5 and 9 mM nitroethane compared to numbers recovered from controls or monensin-containing treatments, which may explain ruminal adaptation to lower nitroethane treatments. 相似文献
233.
Federico Casale Gianluigi Nieddu Elisa Burdino Davide A. L. Vignati Carlo Ferretti Giancarlo Ugazio 《Water, air, and soil pollution》2009,196(1-4):141-149
Several studies have shown the association between ambient particulate matter (PM) and adverse health effects, thus highlighting the need to limit the anthropogenic sources of PM, especially motor vehicle emissions. PM exposure is commonly monitored as mass concentration of PM10 or PM2.5, although increasing toxicity with decreasing aerodynamic diameter has been reported. In the present study an analysis was performed of the concentration and size distribution of airborne PM fractions collected at street level in the city center of Turin, Italy, to verify the usefulness of “ecological” days with traffic limitations. PM levels were determined daily at five different outdoor sites, from Thursday to Tuesday for 7 weeks (five with “ecological” Sunday, two with normal traffic density). Air sampling was performed using a six-channel laser particle counter to determine the number of particles (n°/l) in six size ranges between 0.3 and 10 μm. Climatic conditions and indoor PM levels were also monitored. The PM size distribution was constant for all the samples tested, with the 90% of the particles smaller than 0.5 μm, suggesting that measurements for count are needed in addition to the traditional ones based on the mass. The total number of particles was highly variable comparing days or weeks of monitoring, but much less among the sites of air sampling. The restriction of motor vehicle circulation has not determined any significant effect on PM levels and, in the winter period, PM0.5 peak concentrations were measured also on the ecological days. 相似文献
234.
Elisa Petranich Alessandro Acquavita Stefano Covelli Andrea Emili 《Journal of Soils and Sediments》2017,17(7):1986-1998
Purpose
The Marano and Grado Lagoon (Italy) has been affected by trace metal(oid) contamination in the last century, especially mercury, from both industrial and long-term mining activities. The uptake and distribution of trace metal(oid)s in halophytes were determined in two selected salt marshes. To evaluate the potential activity of plants as phytoremediation, the bioconcentration and translocation factors (BCF and TF, respectively) were calculated.Materials and methods
In both salt marshes, individuals of Sarcocornia fruticosa L. and Limonium vulgare L., two of the most abundant halophytes in this environment, were sampled. The aboveground biomass (stems and leaves) was collected and sealed in plastic bags. Once the stems were removed, the belowground biomass and the attached rhizo-sediment were sampled using a single gouge auger sampler. The sediment cores obtained were sectioned on field to a maximum depth of 15 cm. The roots were carefully separated from the rhizo-sediment in the laboratory. The sediment, roots, leaves, and stems were freeze-dried, finely ground, and homogenized. Samples were totally decomposed, using a mixture of mineral acids in a closed microwave system, and analyzed for trace metal(oid) content by ICP-AES. The total Hg content in the solid phase was determined by DMA-80.Results and discussion
Metal(oid) concentrations in roots were usually up to one or two orders of magnitude higher than in stems and leaves. The exceptions are Cd and Ni, which levels were not detectable, and Cr in stems of both halophytes where the concentration reached up to four times more than in roots. Commonly, trace metal(oid) contents were higher in stems than in leaves, except for Zn. Considering all BCF data, a sequence of metal(oid)s preferentially transferred from sediment to belowground biomass of the two plants is Cd > Mn > As > Pb. This sequence does not coincide for the two salt marshes, except for Cd, probably due to the different source of metal(oid)s in sediments and/or some site-specific lithogenic properties. Metal(oid)s accumulated from rhizo-sediment were largely retained in roots as shown by TF values <1.Conclusions
The general trend arising from BCF and TF reveals that root tissues accumulate significantly greater amounts of metal(oid)s than the aerial part, thus indicating high plant bioavailability of the substrate metal(oid)s as well as their limited translocation to the aboveground biomass. Our results suggest that both salt marshes investigated act as a sink, and only sporadically as a possible source, for several trace metal(oid)s which are not promptly available for the environment.235.
Antonio Biondi Veerle Mommaerts Guy Smagghe Elisa Viñuela Lucia Zappalà Nicolas Desneux 《Pest management science》2012,68(12):1523-1536
Spinosyn‐based products, mostly spinosad, have been widely recommended by extension specialists and agribusiness companies; consequently, they have been used to control various pests in many different cropping systems. Following the worldwide adoption of spinosad‐based products for integrated and organic farming, an increasing number of ecotoxicological studies have been published in the past 10 years. These studies are primarily related to the risk assessment of spinosad towards beneficial arthropods. This review takes into account recent data with the aim of (i) highlighting potentially adverse effects of spinosyns on beneficial arthropods (and hence on ecosystem services that they provide in agroecosystems), (ii) clarifying the range of methods used to address spinosyn side effects on biocontrol agents and pollinators in order to provide new insights for the development of more accurate bioassays, (iii) identifying pitfalls when analysing laboratory results to assess field risks and (iv) gaining increasing knowledge on side effects when using spinosad for integrated pest management (IPM) programmes and organic farming. For the first time, a thorough review of possible risks of spinosad and novel spinosyns (such as spinetoram) to beneficial arthropods (notably natural enemies and pollinators) is provided. The acute lethal effect and multiple sublethal effects have been identified in almost all arthropod groups studied. This review will help to optimise the future use of spinosad and new spinosyns in IPM programmes and for organic farming, notably by preventing the possible side effects of spinosyns on beneficial arthropods. Copyright © 2012 Society of Chemical Industry 相似文献
236.
Gutiérrez-Guzmán AV Vicente J Sobrino R Perez-Ramírez E Llorente F Höfle U 《Veterinary microbiology》2012,159(3-4):291-297
Red foxes (Vulpes vulpes), wild boar (Sus scrofa) and Iberian pigs (Sus scrofa domestica) that are raised extensively outdoors, as well as other wild mesomammals from south central Spain and wild boar from Do?ana National Park (DNP), were tested for antibodies against related flaviviruses by ELISA and for antibodies against WNV by VNT. Mean flavivirus seroprevalence according to ELISA was 20.4±7.8% (21 out of 103) in red foxes, 12.6±2.8% (69 out of 545) in wild boars, and 3.3±2.7% (6 out of 177) in Iberian pigs. A stone marten (Martes foina) also tested positive. Flavivirus seroprevalence in wild boar was significantly higher in DNP, and increased with age. Haemolysis of the serum samples limited interpretation of VNT to 28 samples, confirming WNV seroprevalence in one red fox, four Iberian pigs and nine wild boars. ELISA positive, microVNT negative samples suggest presence of non-neutralizing antibodies against WNV or antibodies to other antigenically related flaviviruses. Despite the importance of wetlands for flavivirus maintenance and amplification, WNV/flavivirus seroprevalence in wild boar and red foxes was not associated to wetland habitats. This is the first report of exposure of red foxes to WNV. With view to use of the tested species as sentinels for flavivirus activity, limited exposure of Iberian pigs that would be available for regular sampling, low numbers of foxes collected and concentration of wild boar harvest in the winter season are major drawbacks. 相似文献
237.
Marc Beno?t Davide Rizzo Elisa Marraccini Anna Camilla Moonen Mariassunta Galli Sylvie Lardon Hélène Rapey Claudine Thenail Enrico Bonari 《Landscape Ecology》2012,27(10):1385-1394
Landscape dynamics increasingly challenge agronomists to explain how and why agricultural landscapes are designed and managed by farmers. Nevertheless, agronomy is rarely included in the wide range of disciplines involved in landscape research. In this paper, we describe how landscape agronomy can help explain the relationship between farming systems and agricultural landscape dynamics. For this, we propose a conceptual model of agricultural landscape dynamics that illustrates the specific contribution of agronomy to landscape research. This model describes the relationship between three elements: farming practices, landscape patterns and natural resources. It can stimulate agronomists to deal with research issues in agricultural landscape dynamics and enhance the interdisciplinary integration of farming systems in wider landscape research. On these premises, we discuss the main research issues that will benefit from an active involvement of agronomy, to understand, but also to assess landscape dynamics and to design relevant decision support systems. 相似文献
238.
Luqman RIAZ Tariq MAHMOOD YANG Qingxiang Muhammad Wahab YASIR Audil RASHID Mark S.COYNE Elisa D'ANGELO 《土壤圈》2019,(5)
<正>Dear Editor,Fluoroquinolones(e.g.,ciprofloxacin(CIP),enrofloxacin(ENR),and levofloxacin(LEV))are an extensively used family of antibiotics prescribed for various infections;however,they are also increasingly used 相似文献
239.
Graziella Berta Simonetta Sampo Elisa Gamalero Nadia Massa Philippe Lemanceau 《European journal of plant pathology / European Foundation for Plant Pathology》2005,111(3):279-288
Rhizoctonia solani root-rot is a major soilborne disease causing growth and yield depression. The ability of Glomus mosseae BEG12 and Pseudomonas fluorescens A6RI to suppress this soilborne disease in tomato was assessed by comparing the shoot and root growth of plants infested with R. solani 1556 when protected or not by these beneficial strains. The epiphytic and parasitic growth of the pathogenic R. solani 1556 was compared in the presence and absence of the biocontrol agents by microscopical observations allowing the quantification of roots with hyphae appressed to epidermal cells (epiphytic growth) and of roots with intraradical infection (parasitic growth). The root architecture of the tomato plants under the different experimental conditions was further characterized by measuring total root length, mean root diameter, number of root tips and by calculating degree of root branching. G. mosseae BEG12 and P. fluorescens A6RI fully overcame the growth depression caused by R. solani 1556. This disease suppression was associated with a significant decrease of the epiphytic and parasitic growth of the pathogen together with an increase of root length and of the number of root tips of inoculated tomato plants. The combined effects of G. mosseae BEG12 and P. fluorescens A6RI on pathogen growth and on root morphogenesis are suggested to be involved in the efficient disease suppression. 相似文献
240.
In vitro assessment of quality of citrate‐phosphate‐dextrose‐adenine‐1 preserved feline blood collected by a commercial closed system 下载免费PDF全文