Increased plant tolerance against chrysanthemum yellows phytoplasma (‘Candidatus Phytoplasma asteris’) following double inoculation with Glomus mosseae BEG12 and Pseudomonas putida S1Pf1Rif     

R. D’Amelio  G. Berta  E. Gamalero  N. Massa  L. Avidano  S. Cantamessa  G. D’Agostino  D. Bosco  C. Marzachì 《Plant pathology》2011,60(6):1014-1022

The aim of this work was to assess the effects of a combined inoculum of a rhizobacterium and an arbuscular mycorrhizal (AM) fungus on plant responses to phytoplasma infection, and on phytoplasma multiplication and viability in Chrysanthemum carinatum plants infected by chrysanthemum yellows phytoplasma (CY). Combined inoculation with Glomus mosseae BEG12 and Pseudomonas putida S1Pf1Rif resulted in some resistance to phytoplasma infection (about 30%), delayed symptom expression in nonresistant plants, improved growth of the aerial part of the infected plants (+68·1%), and altered root morphology (root tip number: +49·9%; branching degree: +82·8%). Combined inoculation with the two beneficial microorganisms did not alter CY multiplication and viability. In inoculated and infected plants, phytoplasma morphology was typical of senescent cells. A more active and efficient root system in double‐inoculated plants probably mediated the effects of the two rhizospheric microorganisms in the infected plants. The practical application of rhizospheric microorganisms for mitigating phytoplasma damage, following evaluation under field conditions, represents an additional tool for the integrated management of phytoplasmosis.  相似文献   

Accuracy of the composite somatic cell count to detect intra-mammary infection in dairy cows using latent class analysis     

Claudina Vissio  Silvana Andrea Dieser  Héctor Luis Agnelli  Liliana Mónica Odierno  Alejandro José Larriestra 《Preventive veterinary medicine》2014

The somatic cell count (SCC) is considered an important indicator of intra-mammary infection (IMI). The purpose of this study was to determine the accuracy of both SCC and culture to detect IMI and their conditional dependence by means of latent class methods. This study involved 175 dairy cows from 2 herds with different udder infection prevalences. Quarter and composite milk samples were collected for SCC and bacteriological culture. Latent-class models using Bayesian methods were used to estimate test sensitivity (Se) and specificity (Sp) and population prevalence. The models ran involved only major mastitis pathogens and composite SCC (CSCC). Five thresholds between 100,000 and 300,000 cells/mL were evaluated and the receiver operating characteristics (ROC) curve analysis was performed. Fifty-five percent of the cows had CSCC ≥200,000 cells/mL and 95.4% of the cows had at least one infected quarter either with minor or major pathogens. Considering a threshold of 150,000 cells/mL, the estimated Se and Sp for the CSCC were, 0.80 (95% CrI 0.71–0.88) and 0.57 (95% CrI 0.44–0.71), respectively. The estimated culture Se and Sp were 0.83 (95% CrI 0.73–0.93) and 0.89 (95% CrI 0.74–0.98), respectively. There was no evidence of dependence between CSCC and culture. The area under curve for CSCC was 0.72. To the best of our knowledge, this is the first report of the CSCC accuracy to detect IMI for major pathogens considering the effect of culture misclassification. The estimates provided here could help to examine the performance of sampling schemes based on CSCC to manage udder health.  相似文献   

A Comparative In Vitro Evaluation of the Anti-Inflammatory Effects of a Tisochrysis lutea Extract and Fucoxanthin     

Elisabetta Bigagli  Mario D&#x;Ambrosio  Lorenzo Cinci  Alberto Niccolai  Natascia Biondi  Liliana Rodolfi  Luana Beatriz Dos Santos Nascimiento  Mario R. Tredici  Cristina Luceri 《Marine drugs》2021,19(6)

In this study, we compared the effects of a Tisochrysis lutea (T. lutea) F&M-M36 methanolic extract with those of fucoxanthin (FX) at equivalent concentration, on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. The T. lutea F&M-M36 methanolic extract contained 4.7 mg of FX and 6.22 mg of gallic acid equivalents of phenols per gram. HPLC analysis revealed the presence of simple phenolic acid derivatives. The T. lutea F&M-M36 extract exhibited a potent and concentration-dependent inhibitory activity against COX-2 dependent PGE2 production compared to FX alone. Compared to LPS, T. lutea F&M-M36 extract and FX reduced the expression of IL-6 and of Arg1 and enhanced that of IL-10 and of HO-1; T. lutea F&M-M36 extract also significantly abated the expression of NLRP3, enhanced mir-223 expression and reduced that of mir-146b, compared to LPS (p < 0.05). These findings indicate that T. lutea F&M-M36 methanolic extract has a peculiar anti-inflammatory activity against COX-2/PGE2 and NLRP3/mir-223 that might be attributable to the known anti-inflammatory effects of simple phenolic compounds found in the extract that may synergize with FX. Our data suggest that T. lutea F&M-M36 may serve as a source of anti-inflammatory compounds to be further evaluated in in vivo models of inflammation.  相似文献   

Cassava common mosaic virus infection causes alterations in chloroplast ultrastructure,function, and carbohydrate metabolism of cassava plants     

Andrea A. Zanini  Liliana Di Feo  Dario F. Luna  Pablo Paccioretti  Agostina Collavino  Marianela S. Rodriguez 《Plant pathology》2021,70(1):195-205

Cassava common mosaic virus (CsCMV) is a potexvirus that causes systemic infections in cassava plants, leading to chlorotic mosaic and producing significant yield losses. To date, the physiological alterations and the mechanism underlying biotic stress during the cassava–CsCMV compatible interaction remains unknown. In this study, we found that CsCMV infection adversely modified chloroplast structure and had functional effects on chloroplasts in source leaves during the course of viral infection. Extrusion of the chloroplast membrane with amoeboid-shaped appearance and disorganized grana stacks were observed in infected mesophyll cells. These alterations were associated with up to 35% reduction of relative chlorophyll content, and a decline of CO₂ fixation (13.5% and 24.2% at 90 and 210 days after planting, respectively). The effects of CsCMV infection on the performance index on absorption basis dropped up to 37%. The analysis of chlorophyll a fluorescence showed a progressive loss of both oxygen evolving complex activity and “connectivity” within the tripartite system (core antenna-LHCII-reaction centre). Here, we report the latter phenomenon for the first time in a viral infection. The oxidative stress process was observed in CsCMV-infected plants (20.8% reduction of antioxidant capacity with respect to noninfected plants). Other effects of the pathogen included reduction of starch and maltose content in source leaves, and a significant increase (24.7%) of the sucrose:starch ratio, which indicates an altered pattern of carbon allocation. Our results suggest that CsCMV induces chloroplast distortion associated with progressive chloroplast function loss and diversion of carbon flux in source leaf tissue, leading to the loss of cassava tuber yield.  相似文献   

What is your diagnosis? Cutaneous nodules and atypical blood cells in a dog          下载免费PDF全文

Ricardo Marcos  Ana Canadas  Liliana Leite‐Martins  Jorge Ribeiro  Joana Santos  Augusto de Matos  John W. Harvey  Marta Santos 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2018,47(2):317-319

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Wild halophytic species as forage sources: Key aspects for plant breeding     

Lorena del Rosario Marinoni  Juan Marcelo Zabala  Edith Liliana Taleisnik  Gustavo Enrique Schrauf  Geraldina Alicia Richard  Pablo Andrs Tomas  Julio Alberto Giavedoni  Jos Francisco Pensiero 《Grass and Forage Science》2019,74(3):321-344

The use of wild halophytic species as forage resources in saline environments has gained increasing attention. Argentina ranks third in area of saline soils in the world, with a third of its territory showing various degrees of salinity, sodicity and/or alkalinity. On this type of soils, rangelands are the main forage resource for livestock production. Many wild species have forage potential and can also be used for the rehabilitation of rangelands and for intercropping. Information about these species, as well as on the physiological and genetic bases associated with salinity tolerance, provides relevant tools for efficient selection methods. This study addresses Argentine wild halophyte species with forage potential and describes selection criteria with an emphasis on the following taxa: (a) Poaceae: subfamily Chloridoideae and tribes Paniceae and Triticeae, (b) Fabaceae and (c) Amaranthaceae (formerly known as Chenopodiaceae). The review is intended to contribute to the general discussion on strategies for the improvement of wild plant genetic resources, using forage species naturally growing in saline soils in Argentina as a case study.  相似文献   

Transformation of Anaplasma marginale     

Roderick F. Felsheim  Adela S. Oliva Chávez  Guy H. Palmer  Liliana Crosby  Anthony F. Barbet  Timothy J. Kurtti  Ulrike G. Munderloh 《Veterinary parasitology》2010,167(2-4):167-174

The tick-borne pathogen, Anaplasma marginale, has a complex life cycle involving ruminants and ixodid ticks. It causes bovine anaplasmosis, a disease with significant economic impact on cattle farming worldwide. The obligate intracellular growth requirement of the bacteria poses a challenging obstacle to their genetic manipulation, a problem shared with other prokaryotes in the genera Anaplasma, Ehrlichia, and Rickettsia. Following our successful transformation of the human anaplasmosis agent, A. phagocytophilum, we produced plasmid constructs (a transposon bearing plasmid, pHimarAm-trTurboGFP-SS, and a transposase expression plasmid, pET28Am-trA7) designed to mediate random insertion of the TurboGFP and spectinomycin/streptomycin resistance genes by the Himar1 allele A7 into the A. marginale chromosome. In these trans constructs, expression of the fluorescent and the selectable markers on the transposon, and expression of the transposase are under control of the A. marginale tr promoter. Constructs were co-electroporated into A. marginale St. Maries purified from tick cell culture, and bacteria incubated for 2 months under selection with a combination of spectinomycin and streptomycin. At that time, ≤1% of tick cells contained colonies of brightly fluorescent Anaplasma, which eventually increased to infect about 80–90% of the cells. Cloning of the insertion site in E. coli and DNA sequence analyses demonstrated insertion of the entire plasmid pHimarAm-trTurboGFP-SS encoding the transposon in frame into the native tr region of A. marginale in an apparent single homologous crossover event not mediated by the transposase. Transformants are fastidious and require longer subculture intervals than wild type A. marginale. This result suggests that A. marginale, as well as possibly other species of Anaplasma and Ehrlichia, can be transformed using a strategy of homologous recombination.  相似文献   

Fossil evidence for evolution of the shape and color of penguin feathers     

Clarke JA  Ksepka DT  Salas-Gismondi R  Altamirano AJ  Shawkey MD  D'Alba L  Vinther J  DeVries TJ  Baby P 《Science (New York, N.Y.)》2010,330(6006):954-957

Penguin feathers are highly modified in form and function, but there have been no fossils to inform their evolution. A giant penguin with feathers was recovered from the late Eocene (~36 million years ago) of Peru. The fossil reveals that key feathering features, including undifferentiated primary wing feathers and broad body contour feather shafts, evolved early in the penguin lineage. Analyses of fossilized color-imparting melanosomes reveal that their dimensions were similar to those of non-penguin avian taxa and that the feathering may have been predominantly gray and reddish-brown. In contrast, the dark black-brown color of extant penguin feathers is generated by large, ellipsoidal melanosomes previously unknown for birds. The nanostructure of penguin feathers was thus modified after earlier macrostructural modifications of feather shape linked to aquatic flight.  相似文献   

Measurement of nuclear DNA content of the genus <Emphasis Type="Italic">Trifolium</Emphasis> L. as a measure of genebank accession identity     

Liliana Vižintin  Borut Bohanec 《Genetic Resources and Crop Evolution》2008,55(8):1323-1334

The collection, identification and maintenance of genebank accessions of the genus Trifolium is a major task because of the large number of genera and their occasional morphological similarity. We investigated whether the measurement of nuclear DNA content can serve as an additional criterion for identification of mislabeled accessions. Relative nuclear DNA content was determined by flow cytometry measurements for a total of 151 genebank accessions of 23 Trifolium species with notable agronomical value. Among 23 species analyzed, 15 were found to possess a uniform relative nuclear DNA content, with intraspecific variability of the majority of analyzed species lower than 5%. Within six Trifolium species, 1–2 atypical accessions with outstanding differences in relative DNA content, chromosome number and morphological features were found. In T. hybridum and partially in T. ambiguum these outstanding differences could be ascribed to variations in accession ploidy level. For the remaining atypical accessions, the determined nuclear DNA content, chromosome number and morphological features were not related to those characteristic of the species. Additionally taxonomic identity of atypical accessions was determined using ITS region sequencing and morphological observations. We propose flow cytometric measurements of nuclear DNA content as simple and reliable technique which can be used at seedling stage to verify identity and genetic stability of Trifolium genebank accessions.  相似文献   

Dynamics of moisture regime and its reconstruction from a tree-ring width chronology of Pinus sylvestris in the downstream basin of the Selenga River,Russia     

BELOKOPYTOVA Liliana 《干旱区科学》2018,10(6):877-891

Regional tree-ring width chronology of the Scots pine (Pinus sylvestris L.) was constructed from 8 sites in the forest-steppe belt situated in the foothills of the Selenga River basin, Russia. Moisture information contained in tree-ring width chronology was obtained through linear regression reconstruction models of annual August-July precipitation and annual water discharge of the Selenga River during the period 1767-2015. Comparison of the smoothed series allowed estimating long-term variation component of these moisture regime parameters with a high precision. At the same time, regional drought indices are less correlated with pine radial growth, because they have contribution of the other environmental variables, which are much less reflected in the tree-ring of the investigated pine forest stands. Reconstructed dynamic of the moisture regime parameters is supported by documental evident of many socially significant events in the regional history, such as crop failures caused by both droughts and floods, and catastrophic fire in the Irkutsk City in 1879. Also, dependence of the amount of precipitation in the study area on the atmospheric circulation in Central Asia is revealed to have a similar pattern with other regions, i.e., a negative relationship of precipitation with the development of large high atmospheric pressure area within its center in the Altai and Tianshan mountains.  相似文献