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991.
Anurag Dagar Clara Pons Puig Cristina Marti Ibanez Fiorenza Ziliotto Claudio Bonghi Carlos H. Crisosto Haya Friedman Susan Lurie Antonio Granell 《Tree Genetics & Genomes》2013,9(1):223-235
Gene expression at harvest was compared for two stone fruit cultivars, a peach and its near-isogenic nectarine mutant, using two microarray platforms, μPEACH1.0 and ChillPeach. Together, both platforms covered over 6,000 genes out of which 417 were differentially expressed between the fruits of the two cultivars at a p value of 0.05. A total of 47 genes in nectarine and 60 genes in peach were at least twofold higher relative to each other. Nectarine had much better storage characteristics than peach and could be stored for over 5 weeks at 5 °C without storage disorders. In an attempt to determine whether gene expression at harvest could give an indication of storage potential, the expression analysis of the two cultivars was compared to that of two genotypes with different sensitivities to chilling injury. Principal component analysis of gene expression results across four fruit types differing in chilling sensitivity resulted in 41 genes whose expression levels separated the fruits according to sensitivity to storage disorders, suggesting that the genes have a role in cold response adaptation. 相似文献
992.
Clara B. Ocampo Paola A. Caicedo Gloria Jaramillo Raul Ursic Bedoya Olga Baron Idalba M. Serrato Dawn M. Cooper Carl Lowenberger 《PloS one》2013,8(4)
Aedes aegypti is the principal vector of Dengue viruses worldwide. We identified field collected insects with differential susceptibility to Dengue-2 virus (DENv-2) and used isofemale selection to establish susceptible and refractory strains based on midgut infection barriers. Previous experiments had identified higher expression of apoptosis-related genes in the refractory strain. To identify potential molecular mechanisms associated with DENv susceptibility, we evaluated the differential expression of Caspase-16, Aedronc, Aedredd, Inhibitor of apoptosis (AeIAP1) and one member of the RNAi pathway, Argonaute-2 in the midguts and fat body tissues of the selected strains at specific times post blood feeding or infection with DENv-2. In the refractory strain there was significantly increased expression of caspases in midgut and fatbody tissues in the presence of DENv-2, compared to exposure to blood alone, and significantly higher caspase expression in the refractory strain compared with the susceptible strain at timepoints when DENv was establishing in these tissues. We used RNAi to knockdown gene expression; knockdown of AeIAP1 was lethal to the insects. In the refractory strain, knockdown of the pro-apoptotic gene Aedronc increased the susceptibility of refractory insects to DENv-2 from 53% to 78% suggesting a contributing role of this gene in the innate immune response of the refractory strain. 相似文献
993.
Background
Optimal foraging theory predicts that animals will tend to maximize foraging success by optimizing search strategies. However, how organisms detect sparsely distributed food resources remains an open question. When targets are sparse and unpredictably distributed, a Lévy strategy should maximize foraging success. By contrast, when resources are abundant and regularly distributed, simple Brownian random movement should be sufficient. Although very different groups of organisms exhibit Lévy motion, the shift from a Lévy to a Brownian search strategy has been suggested to depend on internal and external factors such as sex, prey density, or environmental context. However, animal response at the individual level has received little attention.Methodology/Principal Findings
We used GPS satellite-telemetry data of Egyptian vultures Neophron percnopterus to examine movement patterns at the individual level during consecutive years, with particular interest in the variations in foraging search patterns during the different periods of the annual cycle (i.e. breeding vs. non-breeding). Our results show that vultures followed a Brownian search strategy in their wintering sojourn in Africa, whereas they exhibited a more complex foraging search pattern at breeding grounds in Europe, including Lévy motion. Interestingly, our results showed that individuals shifted between search strategies within the same period of the annual cycle in successive years.Conclusions/Significance
Results could be primarily explained by the different environmental conditions in which foraging activities occur. However, the high degree of behavioural flexibility exhibited during the breeding period in contrast to the non-breeding period is challenging, suggesting that not only environmental conditions explain individuals'' behaviour but also individuals'' cognitive abilities (e.g., memory effects) could play an important role. Our results support the growing awareness about the role of behavioural flexibility at the individual level, adding new empirical evidence about how animals in general, and particularly scavengers, solve the problem of efficiently finding food resources. 相似文献994.
Clara Theunis Natalia Crespo-Biel Valérie Gafner Maria Pihlgren María Pilar López-Deber Pedro Reis David T. Hickman Oskar Adolfsson Nathalie Chuard Dorin Mlaki Ndao Peter Borghgraef Herman Devijver Fred Van Leuven Andrea Pfeifer Andreas Muhs 《PloS one》2013,8(8)
Progressive aggregation of protein Tau into oligomers and fibrils correlates with cognitive decline and synaptic dysfunction, leading to neurodegeneration in vulnerable brain regions in Alzheimer''s disease. The unmet need of effective therapy for Alzheimer''s disease, combined with problematic pharmacological approaches, led the field to explore immunotherapy, first against amyloid peptides and recently against protein Tau. Here we adapted the liposome-based amyloid vaccine that proved safe and efficacious, and incorporated a synthetic phosphorylated peptide to mimic the important phospho-epitope of protein Tau at residues pS396/pS404. We demonstrate that the liposome-based vaccine elicited, rapidly and robustly, specific antisera in wild-type mice and in Tau.P301L mice. Long-term vaccination proved to be safe, because it improved the clinical condition and reduced indices of tauopathy in the brain of the Tau.P301L mice, while no signs of neuro-inflammation or other adverse neurological effects were observed. The data corroborate the hypothesis that liposomes carrying phosphorylated peptides of protein Tau have considerable potential as safe and effective treatment against tauopathies, including Alzheimer''s disease. 相似文献
995.
Pablo E. Campos Anne L. Buffardi César P. Cárcamo Patricia J. García Clara Buendia Marina Chiappe Geoff P. Garnett Ana Maria Xet-Mull King K. Holmes 《PloS one》2013,8(11)
Background
As part of a community-randomized trial of a multicomponent intervention to prevent sexually transmitted infections, we created Mobile Teams (MTs) in ten intervention cities across Peru to improve outreach to female sex workers (FSW) for strengthened STI prevention services.Methods
Throughout 20 two-month cycles, MTs provided counseling; condoms; screening and specific treatment for Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT), and vaginal Trichomonas vaginalis (TV) infections; and periodic presumptive metronidazole treatment for vaginal infections.Results
MTs had 48,207 separate encounters with 24,814 FSW; numbers of sex work venues and of FSW reached increased steadily over several cycles. Approximately 50% of FSW reached per cycle were new. Reported condom use with last client increased from 73% to 93%. Presumptive metronidazole treatment was accepted 83% of times offered. Over 38 months, CT prevalence declined from 15·4% to 8·2%, and TV prevalence from 7·3% to 2·6%. Among participants in ≥9 cycles, CT prevalence decreased from 12·9% to 6·0% (p <0·001); TV from 4·6% to 1·5% (p <0·001); and NG from 0·8% to 0·4% (p =0·07).Conclusions
Mobile outreach to FSW reached many FSW not utilizing government clinics. Self-reported condom use substantially increased; CT and TV prevalences declined significantly. The community-randomized trial, reported separately, demonstrated significantly greater reductions in composite prevalence of CT, NG, TV, or high-titer syphilis serology in FSW in these ten intervention cities than in ten matched control cities. 相似文献996.
Clara Carpeggiani Paolo Marraccini Maria Aurora Morales Renato Prediletto Patrizia Landi Eugenio Picano 《PloS one》2013,8(11)
Aims
Radiological inappropriateness in medical imaging leads to loss of resources and accumulation of avoidable population cancer risk. Aim of the study was to audit the appropriateness rate of different cardiac radiological examinations.Methods and Principal Findings
With a retrospective, observational study we reviewed clinical records of 818 consecutive patients (67±12 years, 75% males) admitted from January 1-May 31, 2010 to the National Research Council – Tuscany Region Gabriele Monasterio Foundation cardiology division. A total of 940 procedures were audited: 250 chest x-rays (CXR); 240 coronary computed tomographies (CCT); 250 coronary angiographies (CA); 200 percutaneous coronary interventions (PCI). For each test, indications were rated on the basis of guidelines class of recommendation and level of evidence: definitely appropriate (A, including class I, appropriate, and class IIa, probably appropriate), uncertain (U, class IIb, probably inappropriate), or inappropriate (I, class III, definitely inappropriate). Appropriateness was suboptimal for all tests: CXR (A = 48%, U = 10%, I = 42%); CCT (A = 58%, U = 24%, I = 18%); CA (A = 45%, U = 25%, I = 30%); PCI (A = 63%, U = 15%, I = 22%). Top reasons for inappropriateness were: routine on hospital admission (70% of inappropriate CXR); first line application in asymptomatic low-risk patients (42% of CCT) or in patients with unchanged clinical status post-revascularization (20% of CA); PCI in patients either asymptomatic or with miscellaneous symptoms and without inducible ischemia on non-invasive testing (36% of inappropriate PCI).Conclusion and Significance
Public healthcare system – with universal access paid for with public money – is haemorrhaging significant resources and accumulating avoidable long-term cancer risk with inappropriate cardiovascular imaging prevention. 相似文献997.
Clara Prats Alba Gomez-Cabello Pernille Nordby Jesper L. Andersen J?rn W. Helge Flemming Dela Otto Baba Thorkil Ploug 《PloS one》2013,8(10)
Skeletal muscle energy metabolism has been a research focus of physiologists for more than a century. Yet, how the use of intramuscular carbohydrate and lipid energy stores are coordinated during different types of exercise remains a subject of debate. Controversy arises from contradicting data from numerous studies, which used different methodological approaches. Here we review the “pros and cons” of previously used histochemical methods and describe an optimized method to ensure the preservation and specificity of detection of both intramyocellular carbohydrate and lipid stores. For optimal preservation of muscle energy stores, air drying cryosections or cycles of freezing-thawing need to be avoided. Furthermore, optimization of the imaging settings in order to specifically image intracellular lipid droplets stained with oil red O or Bodipy-493/503 is shown. When co-staining lipid droplets with associated proteins, Bodipy-493/503 should be the dye of choice, since oil red O creates precipitates on the lipid droplets blocking the light. In order to increase the specificity of glycogen stain, an antibody against glycogen is used. The resulting method reveals the existence of two metabolically distinct myosin heavy chain I expressing fibers: I-1 fibers have a smaller crossectional area, a higher density of lipid droplets, and a tendency to lower glycogen content compared to I-2 fibers. Type I-2 fibers have similar lipid content than IIA. Exhaustive exercise lead to glycogen depletion in type IIA and IIX fibers, a reduction in lipid droplets density in both type I-1 and I-2 fibers, and a decrease in the size of lipid droplets exclusively in type I-1 fibers. 相似文献
998.
Clara Cristina Jost Mafra 《Ethnos》2013,78(4):448-468
Taking into account the composition of Pentecostalism – a mixture of, on one side, a Protestant tradition that allows the constitution of the ‘sincere person’, and, on the other side, the enchanted aspects of personhood – what happens when this message is disseminated in a context with a long Catholic tradition by ‘translators’ socialized in the Catholic culture; in other words, by people with a particular interpretation of the Protestant tradition? In this article, the author explores this question and shows how the Catholic framing impacts the arrangements for accommodating the semiotic ideologies of ‘sincerity’ and ‘saintliness’ within Pentecostal religiosity, resulting in singular manifestations of the collective project and of the regional Christian Person. 相似文献
999.
Clara Ros‐Simó Maria Moscoso‐Castro Jéssica Ruiz‐Medina Joaquim Ros Olga Valverde 《Journal of neurochemistry》2013,125(5):736-746
Ethanol and 3, 4‐Methylenedioxymethamphetamine (MDMA) are popular recreational drugs widely abused by adolescents that may induce neurotoxic processes associated with behavioural alterations. Adolescent CD1 mice were subjected to ethanol intake using the drinking in the dark (DID) procedure, acute MDMA or a combination. Considering that both drugs of abuse cause oxidative stress in the brain, protein oxidative damage in different brain areas was analysed 72 h after treatment using a proteomic approach. Damage to specific proteins in treated animals was significant in the hippocampus but not in the prefrontal cortex. The damaged hippocampus proteins were then identified by mass spectrometry, revealing their involvement in energy metabolism, structural function, axonal outgrowth and stability, and neurotransmitter release. Mice treated with MDMA displayed higher oxidative damage than ethanol‐treated mice. To determine whether this oxidative damage was affecting hippocampus activity, declarative memory was evaluated at 72 h after treatment using the object recognition assay and the radial arm maze. Although acquisition in the radial arm maze was not impaired by ethanol intake, MDMA treatment impaired long‐term memory in both tests. Therefore, oxidative damage to specific proteins observed under MDMA treatment affects important cellular function on the hippocampus that may contribute to declarative memory deficits. 相似文献
1000.
T. C. Hales Clara Cole-Hawthorne Laurence Lovell Samuel L. Evans 《Plant and Soil》2013,372(1-2):553-565