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581.
Alejandro de la Fuente Alejandro Navarro Stephen E. Williams 《Global Change Biology》2023,29(8):2132-2140
Climate-driven biodiversity erosion is escalating at an alarming rate. The pressure imposed by climate change is exceptionally high in tropical ecosystems, where species adapted to narrow environmental ranges exhibit strong physiological constraints. Despite the observed detrimental effect of climate change on ecosystems at a global scale, our understanding of the extent to which multiple climatic drivers affect population dynamics is limited. Here, we disentangle the impact of different climatic stressors on 47 rainforest birds inhabiting the mountains of the Australian Wet Tropics using hierarchical population models. We estimate the effect of spatiotemporal changes in temperature, precipitation, heatwaves, droughts and cyclones on the population dynamics of rainforest birds between 2000 and 2016. We find a strong effect of warming and changes in rainfall patterns across the elevational-segregated bird communities, with lowland populations benefiting from increasing temperature and precipitation, while upland species show an inverse strong negative response to the same drivers. Additionally, we find a negative effect of heatwaves on lowland populations, a pattern associated with the observed distribution of these extreme events across elevations. In contrast, cyclones and droughts have a marginal effect on spatiotemporal changes in rainforest bird communities, suggesting a species-specific response unrelated to the elevational gradient. This study demonstrated the importance of unravelling the drivers of climate change impacts on population changes, providing significant insight into the mechanisms accelerating climate-induced biodiversity degradation. 相似文献
582.
Adriano Barbosa-Silva Theodoros G Soldatos Ivan LF Magalhães Georgios A Pavlopoulos Jean-Fred Fontaine Miguel A Andrade-Navarro Reinhard Schneider J Miguel Ortega 《BMC bioinformatics》2010,11(1):70
Background
Biological knowledge is represented in scientific literature that often describes the function of genes/proteins (bioentities) in terms of their interactions (biointeractions). Such bioentities are often related to biological concepts of interest that are specific of a determined research field. Therefore, the study of the current literature about a selected topic deposited in public databases, facilitates the generation of novel hypotheses associating a set of bioentities to a common context. 相似文献583.
The lectin from Phaseolus acutifolius var. latifolius has been purified to homogeneity by affinity chromatography using stroma-sephadex, gel filtration and electrofocusing. The purified lectin consists of four subunits of 21 Kd molecular mass each one with 7.4% w/w total carbohydrate. Red cells of human and animal species, are agglutinated but are not inhibited by a series of sugars. Mitogenicity and immunosuppressive activities were demonstrated. Agglutination requires magnesium and calcium ions. 相似文献
584.
Panagiota Koskinioti Antonios A. Augustinos Danilo O. Carvalho Muhammad Misbah-ul-Haq Gulizar Pillwax Lucia Duran de la Fuente Gustavo Salvador-Herranz Rafael Argils Herrero Kostas Bourtzis 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2021,376(1818)
Aedes aegypti is the primary vector of arthropod-borne viruses including dengue, chikungunya and Zika. Vector population control methods are reviving to impede disease transmission. An efficient sex separation for male-only releases is crucial for area-wide mosquito population suppression strategies. Here, we report on the construction of two genetic sexing strains using red- and white-eye colour mutations as selectable markers. Quality control analysis showed that the Red-eye genetic sexing strains (GSS) is better and more genetically stable than the White-eye GSS. The introduction of an irradiation-induced inversion (Inv35) increases genetic stability and reduces the probability of female contamination of the male release batches. Bi-weekly releases of irradiated males of both the Red-eye GSS and the Red-eye GSS/Inv35 fully suppressed target laboratory cage populations within six and nine weeks, respectively. An image analysis algorithm allowing sex determination based on eye colour identification at the pupal stage was developed. The next step is to automate the Red-eye-based genetic sexing and validate it in pilot trials prior to its integration in large-scale population suppression programmes.This article is part of the theme issue ‘Novel control strategies for mosquito-borne diseases’. 相似文献
585.
Daniela de la Fuente Arnaldo Maciá María Eugenia Brentassi Andrea Vanesa Toledo 《Journal of Applied Entomology》2021,145(8):810-821
Delphacodes kuscheli is the main vector of Mal de Río Cuarto, the most important viral disease of maize in Argentina. This planthopper harbours obligate fungal mutualists, known as yeast-like symbiotes (YLS), which play a key role in the host life cycle. Here, we evaluated the efficacy of six systemic fungicides, prothioconazole (P), prothioconazole & trifloxystrobin (PT), pyraclostrobin & epoxiconazole (PE), pyraclostrobin, epoxiconazole & fluxapyroxad (PEF), picoxystrobin & ciproconazole (PC), and tebuconazole (T) on the reduction of the abundance of YLS in nymphs and newly emerged adults, and the impact of such reduction on the vector performance. All fungicides, except PE, reduced the number of YLS in nymphs treated from 3rd instar five days after starting treatments. When 3rd instar nymphs were allowed to reach adulthood, the fungicides P, PT and PC caused the highest nymphal mortality, significantly reduced the number of YLS in newly emerged adults, lengthened development time and negatively affected morphometric variables of females. There was also a trend towards a higher occurrence of brachypters. In females, the fungicides P, PT and PC caused a greater reduction of YLS when nymphs were treated to these fungicides from 3rd instar compared with nymphs treated from 4th instar. In males, the YLS number was significantly less when nymphs were fed on plants treated with P, PT, PC, and T in 3rd instar. This showed that fungicide treatments caused a greater reduction of YLS when they were applied in early stages of development. Our results provide an effective method to reduce the abundance of YLS in D. kuscheli, contributing to understand the ecological role that these symbionts could be playing in the success of this maize planthopper pest. 相似文献
586.
Cell mediated immunity in ageing. 总被引:2,自引:0,他引:2
587.
Sandra Gomez-Fuentes Sarah Hernndez-de la Fuente Valeria Morales-Ruiz Dina Lpez-Recinos Adrin Guevara-Salinas María Cristina Parada-Colin Clara Espitia Adrin Ochoa-Leyva Filiberto Snchez Nelly Villalobos Asiel Arce-Sillas Marisela Hernndez Silvia Ivonne Mora Gladis Fragoso Edda Sciutto Laura Adalid-Peralta 《PLoS neglected tropical diseases》2021,15(2)
The flatworm Taenia solium causes human and pig cysticercosis. When cysticerci are established in the human central nervous system, they cause neurocysticercosis, a potentially fatal disease. Neurocysticercosis is a persisting public health problem in rural regions of Mexico and other developing countries of Latin America, Asia, and Africa, where the infection is endemic. The great variability observed in the phenotypic and genotypic traits of cysticerci result in a great heterogeneity in the patterns of molecules secreted by them within their host.This work is aimed to identify and characterize cysticercal secretion proteins of T. solium cysticerci obtained from 5 naturally infected pigs from Guerrero, Mexico, using 2D-PAGE proteomic analysis. The isoelectric point (IP) and molecular weight (MW) of the spots were identified using the software ImageMaster 2D Platinum v.7.0. Since most secreted proteins are impossible to identify by mass spectrometry (MS) due to their low concentration in the sample, a novel strategy to predict their sequence was applied. In total, 108 conserved and 186 differential proteins were identified in five cysticercus cultures. Interestingly, we predicted the sequence of 14 proteins that were common in four out of five cysticercus cultures, which could be used to design vaccines or diagnostic methods for neurocysticercosis. A functional characterization of all sequences was performed using the algorithms SecretomeP, SignalP, and BlastKOALA. We found a possible link between signal transduction pathways in parasite cells and human cancer due to deregulation in signal transduction pathways. Bioinformatics analysis also demonstrated that the parasite release proteins by an exosome-like mechanism, which could be of biological interest. 相似文献
588.
589.
590.
Sara Ferrando-Martínez Mónica de la Fuente Juan Miguel Guerrero Manuel Leal M. Ángeles Muñoz-Fernández 《Revista espa?ola de geriatría y gerontología》2013
Age-related biological deterioration also includes immune system deterioration and, in consequence, a rise in the incidence and prevalence of infections and cancers, as well as low responses to vaccination strategies. Out of all immune cell subsets, T-lymphocytes seem to be involved in most of the age-related defects. Since T-lymphocytes mature during their passage through the thymus, and the thymus shows an age-related process of atrophy, thymic regression has been proposed as the triggering event of this immune deterioration in elderly people. Historically, it has been accepted that the young thymus sets the T-lymphocyte repertoire during the childhood, whereupon atrophy begins until the elderly thymus is a non-functional evolutionary trace. However, a rising body of knowledge points toward the thymus functioning during adulthood. In the elderly, higher thymic function is associated with a younger immune system, while thymic function failure is associated with all-cause mortality. Therefore, any new strategy focused on the improvement of the elderly quality of life, especially those trying to influence the immune system, should take into account, together with peripheral homeostasis, thymus function as a key element in slowing down age-related decline. 相似文献