Analysis of Magnetoencephalography Signals from Alzheimer’s Disease Patients Using Granger Causality

Producción CientíficaThe aim of this study was to analyze resting-state magnetoencephalography (MEG) activity in Alzheimer’s disease (AD) by means of Granger Causality (GC), an effective connectivity measure that provides an estimation of the information flow between brain regions. For this task, five minutes of MEG recordings were acquired with a 148-channel whole-head magnetometer from 36 AD patients and 26 healthy controls. Abnormalities in AD connectivity were found in the five typical frequency bands: delta (δ, 1-4 Hz), theta (θ, 4-8 Hz), alpha (α, 8-13 Hz), beta (β, 13-30 Hz), and gamma (γ, 30-65 Hz). Noteworthy increments in delta band and decrements in beta and gamma bands revealed disrupted connections in AD brain activity. Our analyses suggest that GC may be useful to characterize the brain impairment in AD.Ministerio de Economía y Competitividad (TEC2014-53196-R)Junta de Castilla y León (VA059U13 y BIO/VA08/15

Sinorhizobium fredii HH103 RirA is required for oxidative stress resistance and efficient symbiosis with Soybean

Members of Rhizobiaceae contain a homologue of the iron-responsive regulatory protein RirA. In different bacteria, RirA acts as a repressor of iron uptake systems under iron-replete conditions and contributes to ameliorate cell damage during oxidative stress. In Rhizobium leguminosarum and Sinorhizobium meliloti, mutations in rirA do not impair symbiotic nitrogen fixation. In this study, a rirA mutant of broad host range S. fredii HH103 has been constructed (SVQ780) and its free-living and symbiotic phenotypes evaluated. No production of siderophores could be detected in either the wild-type or SVQ780. The rirA mutant exhibited a growth advantage under iron-deficient conditions and hypersensitivity to hydrogen peroxide in iron-rich medium. Transcription of rirA in HH103 is subject to autoregulation and inactivation of the gene upregulates fbpA, a gene putatively involved in iron transport. The S. fredii rirA mutant was able to nodulate soybean plants, but symbiotic nitrogen fixation was impaired. Nodules induced by the mutant were poorly infected compared to those induced by the wild-type. Genetic complementation reversed the mutant’s hypersensitivity to H2O2, expression of fbpA, and symbiotic deficiency in soybean plants. This is the first report that demonstrates a role for RirA in the Rhizobium-legume symbiosis.Andalucian Government Grant No. P11-CVI-7500Spanish Government Grant Nos. BIO2013-42801-P and BIO2016-78409-REuropean Regional Development Funds (ERDF)VPPI (V Plan Propio de Investigación) of University of Seville

Alterations of Effective Connectivity Patterns in Mild Cognitive Impairment: An MEG Study

Producción CientíficaNeuroimaging techniques have demonstrated over the years their ability to characterize the brain abnormalities associated with different neurodegenerative diseases. Among all these techniques, magnetoencephalography (MEG) stands out by its high temporal resolution and noninvasiveness. The aim of the present study is to explore the coupling patterns of resting-state MEG activity in subjects with mild cognitive impairment (MCI). To achieve this goal, five minutes of spontaneous MEG activity were acquired with a 148- channel whole-head magnetometer from 18 MCI patients and 26 healthy controls. Interchannel relationships were investigated by means of two complementary coupling measures: coherence and Granger causality. Coherence is a classical method of functional connectivity, while Granger causality quantifies effective (or causal) connectivity. Both measures were calculated in the five conventional frequency bands: delta (d, 1-4 Hz), theta (q, 4-8 Hz), alpha (a, 8-13 Hz), beta (b, 13-30 Hz), and gamma (g, 30-45Hz). Our results showed that connectivity values were lower for MCI patients than for controls in all frequency bands. However, only Granger causality revealed statistically significant differences between groups (p-values < 0.05, FDR corrected Mann-Whitney U-test), mainly in the beta band. Our results support the role of MCI as a disconnection syndrome, which elicits early alterations in effective connectivity patterns. These findings can be helpful to identify the neural substrates involved in prodromal stages of dementia.This research was supported by ‘Ministerio de Economía y Competitividad’ and ‘European Regional Development Fund’ under project TEC2014-53196-R, by ‘European Commission’ and ‘European Regional Development Fund’ under project ‘Análisis y correlación entre el genoma completo y la actividad cerebral para la ayuda en el diagnóstico de la enfermedad de Alzheimer’ (‘Cooperation Programme Interreg V-A Spain-Portugal POCTEP 2014-2020’), and by ‘Consejería de Educación de la Junta de Castilla y León’ under project VA037U16. Pablo Núñez was in receipt of a ‘Promoción de empleo joven e implantación de la Garantía Juvenil en I+D+i’ grant from ‘Ministerio de Economía y Competitividad’ and University of Valladolid

Analysis of Spontaneous EEG Activity in Alzheimer’s Disease Using Cross-Sample Entropy and Graph Theory

Producción CientíficaThe aim of this pilot study was to analyze spontaneous electroencephalography (EEG) activity in Alzheimer’s disease (AD) by means of Cross-Sample Entropy (Cross-SampEn) and two local measures derived from graph theory: clustering coefficient (CC) and characteristic path length (PL). Five minutes of EEG activity were recorded from 37 patients with dementia due to AD and 29 elderly controls. Our results showed that Cross-SampEn values were lower in the AD group than in the control one for all the interactions among EEG channels. This finding indicates that EEG activity in AD is characterized by a lower statistical dissimilarity among channels. Significant differences were found mainly for fronto-central interactions (p < 0.01, permutation test). Additionally, the application of graph theory measures revealed diverse neural network changes, i.e. lower CC and higher PL values in AD group, leading to a less efficient brain organization. This study suggests the usefulness of our approach to provide further insights into the underlying brain dynamics associated with AD.Ministerio de Economía y Competitividad (TEC2014-53196-R)Junta de Castilla y León (proyecto VA037U16 y BIO/VA08/15

Residuos de productos lácteos y de grasa de carne en dos recipientes cerámicos de la Edad del Bronce del Valle Medio del Duero

A través de análisis por cromatografía de gases-espectrometría de masas y del estudio de las reacciones inmunoquímicas de la caseína, se ha logrado identificar el residuo de sendos vasos cerámicos del horizonte inicial de Cogotas I de la provincia de Valladolid: un preparado de leche con cereales y grasa de carne. A partir de ahí, se insiste en la importancia de la actividad ganadera entre las comunidades del Bronce Medio de la Meseta y se considera, asimismo, la posibilidad de que el contenido de tales vasijas "completas" representara una ofrenda entre tantas otras atestiguadas en los "campos de hoyos" cogotianos.Through the application of Gas Chromatography-Mass Spectrometry and the determination of casein based on its immunochemical reactions, residues of animal fats and dairy products have been detected in two Bronze Age (Early Cogotas I culture) pottery vessels from Valladolid. The importance of cattle raising activities among the Middle Bronze Age societies of the Spanish Meseta is assessed here. It is argued that the original contents deposited in these vessels may have been offerings, as is the case with other materials that are found in the Cogotas I pit fields

Etología. Introducción a la ciencia del comportamiento

1ª ed., 3ª reimp.El objetivo de este libro es proporcionar una introducción a la Etología. Ésta ciencia responde al interés por profundizar en el conocimiento de las costumbres animales; por comprender la variedad de comportamientos que en diferentes situaciones exhiben los individuos de diferentes especies. Una posible definición de Etología podría ser: el estudio científico del comportamiento de los seres vivos. A lo largo de esta obra se analizan todos los aspectos que tienen que ver con el comportamiento animal, desde las causas y mecanismos de actuación o la adaptación y evolución y el bienestar animal.The purpose of this book is to provide an introduction to Ethology. This science responds to the interest in deepening the knowledge of animal customs; to understand the variety of behaviour that in different situations exhibit individuals of different species. A possible definition of ethology could be: the scientific study of the behavior of living beings. Throughout this book all aspects related to animal behavior, from the causes and mechanisms of action or adaptation and evolution and animal welfare, are analyzed

Regulation and symbiotic significance of nodulation outer proteins secretion in Sinorhizobium fredii HH103

In this work we show that the Sinorhizobium fredii HH103 ttsI gene is essential for the expression of the tts genes and secretion of nodulation outer proteins (Nops). Moreover, we demonstrate for the first time, to our knowledge, that the nod box preceding ttsI is necessary for Nops secretion. TtsI is responsible for the transcriptional activation of nopX, nopA, rhcJ and rhcQ. We confirm that the S. fredii HH103 ttsI gene is activated by NodD1 and repressed by NolR. In contrast, NodD2 is not involved in the regulation of ttsI expression. Despite the dependence of expression of both ttsI and nodA on NodD1 and flavonoids, clear differences in the capacity of some flavonoids to activate these genes were found. The expression of the ttsI and nodA genes was also sensitive to differences in the pH of the media. Secretion of Nops in the ttsI mutant could not be complemented with a DNA fragment containing the ttsI gene and its nod box, but it was restored when a plasmid harbouring the ttsI, rhcC2 and y4xK genes was transferred to the mutant strain. The symbiotic effect of Nops secretion was host-dependent but independent of the type of nodule formed by the host legume. Nops are beneficial in the symbiosis with Glycine max and Glycyrrhiza uralensis, and detrimental in the case of the tropical legume Erythrina variegata

Exopolysaccharide Production by Sinorhizobium fredii HH103 Is Repressed by Genistein in a NodD1-Dependent Manner

In the rhizobia-legume symbiotic interaction, bacterial surface polysaccharides, such as exopolysaccharide (EPS), lipopolysaccharide (LPS), K-antigen polysaccharide (KPS) or cyclic glucans (CG), appear to play crucial roles either acting as signals required for the progression of the interaction and/or preventing host defence mechanisms. The symbiotic significance of each of these polysaccharides varies depending on the specific rhizobialegume couple. In this work we show that the production of exopolysaccharide by Sinorhizobium fredii HH103, but not by other S. fredii strains such as USDA257 or NGR234, is repressed by nod gene inducing flavonoids such as genistein and that this repression is dependent on the presence of a functional NodD1 protein. In agreement with the importance of EPS for bacterial biofilms, this reduced EPS production upon treatment with flavonoids correlates with decreased biofilm formation ability. By using quantitative RT-PCR analysis we show that expression of the exoY2 and exoK genes is repressed in late stationary cultures of S. fredii HH103 upon treatment with genistein. Results presented in this work show that in S. fredii HH103 EPS production is regulated just in the opposite way than other bacterial signals such as Nod factors and type 3 secreted effectors: it is repressed by flavonoids and NodD1 and enhanced by the nod repressor NolR. These results are in agreement with our previous observations showing that lack of EPS production by S. fredii HH103 is not only non-detrimental but even beneficial for symbiosis with soybeanMinisterio de Ciencia e Investigación BIO2011-30229-C02-01Junta de Andalucía P11-CVI-750

Mycorrhizal-assisted phytoremediation and intercropping strategies improved the health of contaminated soil in a peri-urban area

[EN] Soils of abandoned and vacant lands in the periphery of cities are frequently subjected to illegal dumping and can undergo degradation processes such as depletion of organic matter and nutrients, reduced biodiversity, and the presence of contaminants, which may exert an intense abiotic stress on biological communities. Mycorrhizalassisted phytoremediation and intercropping strategies are highly suitable options for remediation of these sites. A two-year field experiment was conducted at a periurban site contaminated with petroleum hydrocarbons and polychlorinated biphenyls, to assess the effects of plant growth (spontaneous plant species, Medicago sativa, and Populus canadensis, alone vs. intercropped) and inoculation of a commercial arbuscular mycorrhizal and ectomycorrhizal inoculum. Contaminant degradation, plant performance, and biodiversity, as well as a variety of microbial indicators of soil health (microbial biomass, activity, and diversity parameters) were determined. The rhizosphere bacterial and fungal microbiomes were assessed by measuring the structural diversity and composition via amplicon sequencing. Establishment of spontaneous vegetation led to greater plant and soil microbial diversity. Intercropping enhanced the activity of soil enzymes involved in nutrient cycling. The mycorrhizal treatment was a key contributor to the establishment of intercropping with poplar and alfalfa. Inoculated and poplar-alfalfa intercropped soils had a higher microbial abundance than soils colonized by spontaneous vegetation. Our study provided evidence of the potential of mycorrhizal-assisted phytoremediation and intercropping strategies to improve soil health in degraded peri-urban areas.This study was supported by the PhytoSUDOE (SOE1/P5/E0189) and Phy2SUDOE (SOE4/P5/E1021) projects funded by the Interreg Sudoe Programme through the European Regional Development Fund (ERDF), PRADA project (PID2019- 110055RB-C21 and PID2019-110055RB-C22) from MINECO, and the Consolidated Research Group of the Basque Government (GV ITO18-16)