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971.
Beatrice Carlsson Elin Kindberg Javier Buesa Gustaf E. Rydell Marta Fos Lidón Rebeca Montava Reem Abu Mallouh Ammi Grahn Jesús Rodríguez-Díaz Juan Bellido Alberto Arnedo G?ran Larson Lennart Svensson 《PloS one》2009,4(5)
In November 2004, 116 individuals in an elderly nursing home in El Grao de Castellón, Spain were symptomatically infected with genogroup II.4 (GII.4) norovirus. The global attack rate was 54.2%. Genotyping of 34 symptomatic individuals regarding the FUT2 gene revealed that one patient was, surprisingly, a non-secretor, hence indicating secretor-independent infection. Lewis genotyping revealed that Lewis-positive and negative individuals were susceptible to symptomatic norovirus infection indicating that Lewis status did not predict susceptibility. Saliva based ELISA assays were used to determine binding of the outbreak virus to saliva samples. Saliva from a secretor-negative individual bound the authentic outbreak GII.4 Valencia/2004/Es virus, but did not in contrast to secretor-positive saliva bind VLP of other strains including the GII.4 Dijon strain. Amino acid comparison of antigenic A and B sites located on the external loops of the P2 domain revealed distinct differences between the Valencia/2004/Es and Dijon strains. All three aa in each antigenic site as well as 10/11 recently identified evolutionary hot spots, were unique in the Valencia/2004/Es strain compared to the Dijon strain. To the best of our knowledge, this is the first example of symptomatic GII.4 norovirus infection of a Lea+b− individual homozygous for the G428A nonsense mutation in FUT2. Taken together, our study provides new insights into the host genetic susceptibility to norovirus infections and evolution of the globally dominating GII.4 viruses. 相似文献
972.
Alexandro Bonifaz Berenice Córdoba-García Tania Simancas-Llanos Marco A. Hernández Erick Martínez-Herrera Andrés Tirado-Sánchez 《Revista iberoamericana de micología》2019,36(1):30-33
Background
Nannizzia nana is a zoophilic dermatophyte that affects animals like pigs, boars and, exceptionally, humans, in whom it causes tinea capitis, as well as tinea corporis and onychomycosis.Case report
Case 1. A previously healthy 8 year-old boy presented to our clinic with a 1-month evolution dermatosis that affected scalp, developing a pseudoalopecic tumor lesion with abundant seropurulent material. The patient had worked in a pig farm. Case 2. A previously healthy 6 year-old girl, sister of the aforementioned child, presented to our clinic with a dermatosis characterized by multiple erythematous-scaly plaques that affected her face, trunk and arms. N. nana was the fungus isolated on culture in both cases. The children were treated with oral griseofulvin and topical ketoconazole that led to clinical and mycological cures.Conclusions
N. nana dermatophytosis, although being rare in humans, can be treated as other cases of dermatophytosis. 相似文献973.
E. Cortés A.A. Kirk J.A. Goolsby P.J. Moran A.E. Racelis M.A. Marcos-García 《Biocontrol Science and Technology》2011,21(11):1369-1373
Arundo donax L. (Poaceae) is native to Mediterranean Europe and invasive in the Rio Grande Basin of North America. Rhizomes from nine sites in France and Spain infested with a candidate control agent, the armoured scale Rhizaspidiotus donacis (Hemiptera: Diaspididae) weighed 50% less than those from nine sites without scale. 相似文献
974.
975.
Proposed links between biodiversity and ecosystem processes have generated intense interest in the linkage between aboveground
net primary productivity (ANPP) and soil C storage. Quantity and quality of ANPP largely depend on plant functional groups
and management practices. In a context of environmental change (that is, land-use and climate) long-term studies of ANPP and
functional groups are gaining interest. However, rapid determination of ANPP and functional groups are often limited in time
and money, resulting in less than ideal sampling schemes and replications. Near-infrared reflectance spectroscopy (NIRS) can
relieve constraints of labor intensive hand-sorting by providing quick, non-destructive, and quantitative analyses of a range
of organic constituents (for example, plant tissues). Here, we investigated the potential of a NIRS method to rapidly predict
harvested green aboveground biomass, the proportion of dead material, and simple functional plant traits, necessary to determine
ANPP and related ecosystem properties. The issue was investigated for two independent grassland experiments of contrasted
long-term field management (high vs. low grazing and N fertilization). Our results show that NIRS analyses are well suited
to determine ANPP (12 and 19% error of prediction) and simple plant traits (error 9%) of contrasted treatment of two independent
multi-species grasslands. Moreover, we show that calibration may be simplified when compared to commonly used protocols, which
offers ecologists enormous analytical power. 相似文献
976.
Véronique Ollivier Varouna Syvannarath Angèle Gros Amena Butt Stéphane Loyau Martine Jandrot-Perrus Beno?t Ho-Tin-Noé 《PloS one》2014,9(8)
Platelets are not only central actors of hemostasis and thrombosis but also of other processes including inflammation, angiogenesis, and tissue regeneration. Accumulating evidence indicates that these “non classical” functions of platelets do not necessarily rely on their well-known ability to form thrombi upon activation. This suggests the existence of non-thrombotic alternative states of platelets activation. We investigated this possibility through dose-response analysis of thrombin- and collagen-induced changes in platelet phenotype, with regards to morphological and functional markers of platelet activation including shape change, aggregation, P-selectin and phosphatidylserine surface expression, integrin activation, and release of soluble factors. We show that collagen at low dose (0.25 µg/mL) selectively triggers a platelet secretory phenotype characterized by the release of dense- and alpha granule-derived soluble factors without causing any of the other major platelet changes that usually accompany thrombus formation. Using a blocking antibody to glycoprotein VI (GPVI), we further show that this response is mediated by GPVI. Taken together, our results show that platelet activation goes beyond the mechanisms leading to platelet aggregation and also includes alternative platelet phenotypes that might contribute to their thrombus-independent functions. 相似文献
977.
Samuel Rommelaere Virginie Millet Thien-Phong Vu Manh Thomas Gensollen Pierre Andreoletti Mustapha Cherkaoui-Malki Christophe Bourges Bertrand Escalière Xin Du Yu Xia Jean Imbert Bruce Beutler Yoshiakira Kanai Bernard Malissen Marie Malissen Anne Tailleux Bart Staels Franck Galland Philippe Naquet 《PloS one》2014,9(8)
978.
Henry F. Howe Yuliana Urincho-Pantaleon Marinés de la Peña-Domene Cristina Martínez-Garza 《Oecologia》2010,164(3):731-740
We explore processes of seed immigration and seedling recruitment before an experimental rainforest restoration matures enough
to affect either. Twenty-four 30 × 30-m plots were fenced in 12 ha of pasture in 2006. Seeds were collected in ninety-six
1-m−2 seed traps; recruits were censused in ~12,000 m2 in which establishment was allowed. We tested effects of distance from forest, living trees, and stumps of trees cut during
site preparation on seed rain in 2007 and effects of these and soil depth on recruits through June 2008. Seed fall and recruitment
were not correlated with distance to forest 90–400 m away, nor to living shade trees outside the 160 × 485-m experimental
grid. Recruitment differed for animal- and wind-dispersed species in a topographically complex landscape. Recruitment of wind-dispersed
species was random with respect to soil depth or distance to recent stumps. Recruitment of animal-dispersed species was multimodal;
partial correlations with number of stumps within 30 m of plots were significant with soil depth held constant (P < 0.025), as were correlations of recruitment with soil depth with number of stumps held constant (P < 0.01). Animal-dispersed recruits were often not conspecifics of adults that had been cut, indicating a legacy of attraction
by fruiting trees of animals bearing seeds from distant sources. Ecological implications are that recruitment in pastures
released from grazing reflects a mix of widely scattered wind-dispersed pioneers and, where animal-dispersed trees exist,
multi-modal and decidedly non-random recruitment of pioneer and later successional animal-dispersed trees from seed banks. 相似文献
979.
Juan Jesús Molina-Rueda María Belén Pascual Francisco M. Cánovas Fernando Gallardo 《Planta》2010,232(6):1471-1483
Glutamate decarboxylase (GAD, EC 4.1.1.15) is a key enzyme in the synthesis of γ-aminobutyric acid (GABA) in higher plants.
A complete cDNA encoding glutamate decarboxylase (GAD, EC 4.1.1.15) was characterized from Pinus pinaster Ait, and its expression pattern was studied to gain insight into the role of GAD in the differentiation of the vascular system.
Pine GAD contained a C-terminal region with conserved residues and a predicted secondary structure similar to the calmodulin
(CaM)-binding domains of angiosperm GADs. The enzyme was able to bind to a bovine CaM-agarose column and GAD activity was
higher at acidic pH, suggesting that the pine GAD can be regulated in vivo by Ca2+/CaM and pH. A polyclonal antiserum was prepared against the pine protein. GAD expression was studied at activity, protein,
and mRNA level and was compared with the expression of other genes during the differentiation of the hypocotyl and induction
of reaction wood. In seedling organs, GABA levels closely matched GAD expression, with high levels in the root and during
lignification of the hypocotyl. GAD expression was also induced in response to the production of compression wood and its
expression matched the pattern of other genes involved in ethylene and 2-oxoglutarate synthesis. The results suggest of a
role of GAD in hypocotyl and stem development in pine. 相似文献
980.
Paulo Silva Arnoldo R. Façanha Rui M. Tavares Hernâni Gerós 《Journal of Plant Growth Regulation》2010,29(1):23-34
Populus euphratica has been used as a plant model to study resistance against salt and osmotic stresses, with recent studies having characterized
the tonoplast and the plasma membrane ATPases, and two Na+/H+ antiporters, homologs of the Arabidopsis tonoplast AtNHX1, were published in databases. In the present work we show that P. euphratica suspension-cultured cells are highly tolerant to high salinity, being able to grow with up to 150 mM NaCl in the culture
medium without substantial modification of the final population size when compared to the control cells in the absence of
salt. At a salt concentration of 300 mM, cells were unable to grow but remained highly viable up to 17 days after subculture.
The addition of a 1-M-NaCl pulse to unadapted cells did not promote a significant loss in cell viability within 48 h. In tonoplast
vesicles purified from cells cultivated in the absence of salt and from salt-stressed cells, vacuolar H+-pyrophosphatase (V-H+-PPase) seemed to be the primary tonoplast proton pump; however, there appears to be a decrease in V-H+-PPase activity with exposure to NaCl, in contrast to the sodium-induced increase in the activity of vacuolar H+-ATPase (V-H+-ATPase). Despite reports that in P. euphratica there is no significant difference in the concentration of Na+ in the different cell compartments under NaCl stress, in the present study, confocal and epifluorescence microscopic observations
using a Na+-sensitive probe showed that suspension-cultured cells subject to a salt pulse accumulated Na+ in the vacuole when compared with control cells. Concordantly, a tonoplast Na+/H+ exchange system is described whose activity is upregulated by salt and, indirectly, by a salt-mediated increase of V-H+-ATPase activity. 相似文献