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101.
Yasmin Vázquez-Santos Yuriana Martínez-Orea Javier Álvarez-Sánchez Noé Manuel Montaño Sara Lucía Camargo-Ricalde Silvia Castillo-Argüero 《Phyton》2021,90(2):605-619
The aim of this study was to analyze the performance of Acaena elongata colonized by arbuscular mycorrhizal
fungi (AMF) to different phosphorus (P) concentrations, as a measure of AMF dependency. A. elongata, is a species from soils where P availability is limited, such as temperate forests. Our research questions were: 1) How do
different P concentrations affect the AMF association in Acaena elongata, and 2) How does the AMF association
influence A. elongata’s growth under different P concentrations? A. elongata’s growth, P content in plant tissue,
AMF colonization and dependency were measured under four P concentrations: control (0 g P kg−1
), low
(0.05 g P kg−1
), intermediate (0.2 g P kg−1
) and high (2 g P kg−1
) in different harvests. A complete randomized
block design was applied. A. elongata’s growth was higher under -AMF in intermediate and high P concentrations, and the lowest growth corresponded to +AMF in the low and intermediate P concentration. We observed
a negative effect on the root biomass under +AMF in intermediate P concentration, while the P concentration had
a positive effect on the leaf area ratio. The AMF colonization in A. elongata decreased in the highest P concentration and it was favored under intermediate P concentration; while the low and the high concentrations generated a cost-benefit imbalance. Our results suggest that the performance of some plant species in soils with
low P availability may not be favored by their association with AMF, but a synergy between AMF and intermediate P concentrations might drive A. elongata’s growth. 相似文献
102.
Quero Gastón Bonnecarrère Victoria Simondi Sebastián Santos Jorge Fernández Sebastián Gutierrez Lucía Garaycochea Silvia Borsani Omar 《Photosynthesis research》2021,150(1-3):97-115
Photosynthesis Research - The photosynthesis process is determined by the intensity level and spectral quality of the light; therefore, leaves need to adapt to a changing environment. The incident... 相似文献
103.
Plant and Soil - The ecological study of root systems lags behind the understanding of the aboveground components of plant communities, mainly due to methodological challenges. As ecological root... 相似文献
104.
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108.
Synaptic transmission is the key system for the information transfer and elaboration among neurons. Nevertheless, a synapse is not a standing alone structure but it is a part of a population of synapses inputting the information from several neurons on a specific area of the dendritic tree of a single neuron. This population consists of excitatory and inhibitory synapses the inputs of which drive the postsynaptic membrane potential in the depolarizing (excitatory synapses) or depolarizing (inhibitory synapses) direction modulating in such a way the postsynaptic membrane potential. The postsynaptic response of a single synapse depends on several biophysical factors the most important of which is the value of the membrane potential at which the response occurs. The concurrence in a specific time window of inputs by several synapses located in a specific area of the dendritic tree can, consequently, modulate the membrane potential such to severely influence the single postsynaptic response. The degree of modulation operated by the synaptic population depends on the number of synapses active, on the relative proportion between excitatory and inbibitory synapses belonging to the population and on their specific mean firing frequencies. In the present paper we show results obtained by the simulation of the activity of a single Glutamatergic excitatory synapse under the influence of two different populations composed of the same proportion of excitatory and inhibitory synapses but having two different sizes (total number of synapses). The most relevant conclusion of the present simulations is that the information transferred by the single synapse is not and independent simple transition between a pre- and a postsynaptic neuron but is the result of the cooperation of all the synapses which concurrently try to transfer the information to the postsynaptic neuron in a given time window. This cooperativeness is mainly operated by a simple mechanism of modulation of the postsynaptic membrane potential which influences the amplitude of the different components forming the postsynaptic excitatory response. 相似文献
109.
Gabriella Gruden Patrizia Carucci Federica Barutta Davina Burt Arianna Ferro Emanuela Rolle Silvia Pinach Maria Lorena Abate Donata Campra Marilena Durazzo 《Cell stress & chaperones》2021,26(1):151
Heat shock protein 27 (HSP27), an intracellular molecular chaperone, is involved in the pathogenesis of cancer by promoting both tumor cell proliferation and resistance to therapy. HSP27 is also present in the circulation and circulating HSP27 (sHSP27) can elicit an autoimmune response with production of antibodies. Levels of sHSP27 are enhanced in patients with hepatocellular carcinoma (HCC); it is, however, unknown whether changes in HSP27 antibody levels occur in patients with HCC and can be exploited as a circulating biomarker of HCC. Our aim was to assess the potential association between newly diagnosed HCC and serum anti-HSP27 antibody levels. In this cross-sectional study, anti-HSP27 antibody levels were measured in serum samples from 71 HCC patients, 80 subjects with chronic liver disease, and 38 control subjects by immunoenzymatic assay. Anti-HSP27 antibody levels did not differ significantly among groups. However, in patients with chronic active hepatitis/cirrhosis, anti-HSP27 levels were significantly higher in subjects with a positive history of alcoholism (p = 0.03). Our data do not support the hypothesis that anti-HSP27 antibody levels may help identify patients with HCC among subjects with chronic liver disease. However, our finding that alcohol-related liver disease is associated with higher anti-HSP27 levels is novel and deserves further investigations. 相似文献
110.
Alonso Alberto Pérez Javier Monroy Silvia López-Rojo Naiara Basaguren Ana Bosch Jaime Boyero Luz 《Ecosystems》2021,24(6):1436-1449
Ecosystems - Leaf litter of alder (Alnus glutinosa) is a key resource to detrital stream food webs. Due to its high quality and palatability, it is readily colonised by microorganisms and consumed... 相似文献