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As part of the human microbiota, the fungus Candida albicans colonizes the oral cavity and other mucosal surfaces of the human body. Commensalism is tightly controlled by complex interactions of the fungus and the host to preclude fungal elimination but also fungal overgrowth and invasion, which can result in disease. As such, defects in antifungal T cell immunity render individuals susceptible to oral thrush due to interrupted immunosurveillance of the oral mucosa. The factors that promote commensalism and ensure persistence of C. albicans in a fully immunocompetent host remain less clear. Using an experimental model of C. albicans oral colonization in mice we explored fungal determinants of commensalism in the oral cavity. Transcript profiling of the oral isolate 101 in the murine tongue tissue revealed a characteristic metabolic profile tailored to the nutrient poor conditions in the stratum corneum of the epithelium where the fungus resides. Metabolic adaptation of isolate 101 was also reflected in enhanced nutrient acquisition when grown on oral mucosa substrates. Persistent colonization of the oral mucosa by C. albicans also correlated inversely with the capacity of the fungus to induce epithelial cell damage and to elicit an inflammatory response. Here we show that these immune evasive properties of isolate 101 are explained by a strong attenuation of a number of virulence genes, including those linked to filamentation. De-repression of the hyphal program by deletion or conditional repression of NRG1 abolished the commensal behaviour of isolate 101, thereby establishing a central role of this factor in the commensal lifestyle of C. albicans in the oral niche of the host.
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Candida albicans , Candidiasis Bucal , Animales , Candidiasis Bucal/microbiología , Proteínas Fúngicas , Ratones , Mucosa Bucal/microbiología , Simbiosis , VirulenciaRESUMEN
PURPOSE: The use of strength and conditioning training in childhood is a hot topic surrounded by myths and misconceptions. Despite scientific evidence supporting the safety and benefits of this training for children, the lack of representation of their voices poses a challenge in designing training programs that meet their specific needs and requirements. METHODS: Children's views, experiences, and perceptions of strength and conditioning training were explored by Write, Draw, Show and Tell techniques. Sixteen grassroots soccer players aged 11-12 years took part in one of 3 focus groups exploring the topic. Data were analyzed following an inductive approach enabling themes to be explored and later deductive analyses using the Youth Physical Activity Promotion model to create pen profile diagrams. RESULTS: Strength and conditioning were frequently associated with muscle growth, coordination, endurance, and rest. Enabling factors included autonomy, resilience, physical development, and training opportunities. Reinforcing factors included social support, social interference, coaches' communication, role models, and the ways of implementation. CONCLUSIONS: Participants favor integrating strength and conditioning into their soccer training rather than conducting it as a separate session, which is reflected in their enjoyment. Nonetheless, children remain apprehensive about the potential effects of this type of training on their growth.
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Using two imaging modalities, that is, Pittsburgh compound B (PiB) positron emission tomography (PET) and diffusion tensor imaging (DTI) the present study tested associations between cortical amyloid-beta (Aß) burden and fornix microstructural changes with cognitive deficits in early Alzheimer's disease (AD), namely deficits in working memory (1-back) processing of visual object categories (faces, places, objects, bodies and verbal material). Second, we examined cortical Aß associations with fornix microstructure. Seventeen early AD patients and 17 healthy-matched controls were included. Constrained spherical deconvolution-based tractography was used to segment the fornix and a control tract the central branch of the superior longitudinal fasciculus (CB-SLF) previously implicated in working memory processes. Standard uptake value ratios (SUVR) of Aß were extracted from 45 cortical/subcortical regions from the AAL atlas and subject to principal component analysis for data reduction. Patients exhibited (i) impairments in cognitive performance (ii) reductions in fornix fractional anisotropy (FA) and (iii) increases in a component that loaded highly on cortical Aß. There were no group differences in CB-SLF FA and in a component loading highly on subcortical Aß. Partial correlation analysis in the patient group showed (i) positive associations between fornix FA and performance for all the visual object categories and (ii) a negative association between the cortical Aß component and performance for the object categories but not for the remaining classes of visual stimuli. A subsequent analysis showed a positive association between overall cognition (performance across distinct 1-back task conditions) with fornix FA but no association with cortical Aß burden, in keeping with influential accounts on early onset AD. This indicates that the fornix degenerates early in AD and contributes to deficits in working memory processing of visual object categories; though it is also important to acknowledge the importance of prospective longitudinal studies with larger samples. Overall, the effect sizes of fornical degeneration on visual working memory appeared stronger than the ones related to amyloid burden.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Péptidos beta-Amiloides , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/psicología , Imagen de Difusión Tensora/métodos , Estudios Prospectivos , Cognición , Tomografía de Emisión de Positrones/métodosRESUMEN
The Laser Interferometer Space Antenna (LISA) will be the first space-based gravitational wave observatory. LISA uses continuous-wave, infrared laser beams propagating among three widely separated spacecrafts to measure their distances with picometer accuracy via time-delay interferometry. These measurements put very high demands on the laser wavefront and are thus very sensitive to any deposits on laser optics that could be induced by laser-induced molecular contamination (LIMC). In this work, we describe the results of an extensive experimental test campaign assessing LIMC related risks for LISA. We find that the LIMC concern for LISA, even considering the high demands on the laser wavefront, may be greatly reduced compared to that observed at shorter wavelengths or with pulsed laser radiation. This result is very promising for LISA as well as for other space missions using continuous-wave, infrared laser radiation, e.g., in free space laser communication or quantum key distribution.
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Bird nests on transmission lines can cause electrical faults which reduce service reliability. To address this problem, since the mid-90s, the Portuguese Transmission System Operator (TSO) has undertaken management actions to discourage white storks Ciconia ciconia from nesting in hazardous locations of the pylons. Here, we compiled and analyzed an 18-year series of data on electrical faults, TSO management actions to tackle these, and stork nests on transmission pylons in Portugal to: (a) determine the relative importance of bird-related faults over the total number of faults; (b) describe variations in bird-related faults across time (season of the year and time of the day); (c) describe spatial variations in bird-related faults and their association with the occurrence of white stork nests on pylons; and (d) analyze the trends, over the years, of the number of white stork nests on pylons, the TSO management actions and their effectiveness in reducing bird-related fault rates. Overall, birds accounted, on average, for 25.3% of the electrical faults in the transmission network, with the vast majority being attributed to white storks. The seasonal pattern of bird-related faults showed higher rates in April and in October-November. Faults occurred more often during the night period, when storks spend more time on the pylons. We found a positive spatial relationship between the electrical fault rate and the proportion of pylons with stork nests (and the correlated number of nests per 100 km of line). There was, however, considerable variation in the fault rates not explained by the stork nest variables, particularly during the non-breeding season. The TSO management actions (namely removal/translocation of nests in hazardous locations of the pylons, installation of anti-perching devices and provision of alternative nesting platforms) significantly reduced, as a whole, the annual number of bird-related faults between 2001 and 2018, despite the three-fold increase in the number of white stork nests on transmission pylons. A deeper understanding of how white storks use the transmission pylons outside the breeding season is needed, so that targeted management actions can be taken to reduce the remaining bird-related fault rates to residual levels.
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Aves , Animales , Reproducibilidad de los Resultados , Estaciones del Año , PortugalRESUMEN
Mutanobactin D is a non-ribosomal, cyclic peptide isolated from Streptococcus mutans and shows activity reducing yeast-to-hyphae transition as well as biofilm formation of the pathogenic yeast Candida albicans. We report the first total synthesis of this natural product, which relies on enantioselective, zinc-mediated 1,3-dipolar cycloaddition and a sequence of cascading reactions, providing the key lipidated γ-amino acid found in mutanobactin D. The synthesis enables configurational assignment, determination of the dominant solution-state structure, and studies to assess the stability of the lipopeptide substructure found in the natural product. The information stored in the fingerprint region of the IR spectra in combination with quantum chemical calculations proved key to distinguishing between epimers of the α-substituted ß-keto amide. Synthetic mutanobactin D drives discovery and analysis of its effect on growth of other members of the human oral consortium. Our results showcase how total synthesis is central for elucidating the complex network of interspecies communications of human colonizers.
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Antifúngicos/farmacología , Péptidos Cíclicos , Antifúngicos/química , Candida albicans/efectos de los fármacos , Hifa/efectos de los fármacos , Modelos Moleculares , Péptidos Cíclicos/síntesis química , Péptidos Cíclicos/química , Péptidos Cíclicos/farmacologíaRESUMEN
Neuroimaging studies have suggested that hMT+ encodes global motion interpretation, but this contradicts the notion that BOLD activity mainly reflects neuronal input. While measuring fMRI responses at 7 Tesla, we used an ambiguous moving stimulus, yielding the perception of two incoherently moving surfaces-component motion-or only one coherently moving surface-pattern motion, to induce perceptual fluctuations and identify perceptual organization size-matched domains in hMT+. Then, moving gratings, exactly matching either the direction of component or pattern motion percepts of the ambiguous stimulus, were shown to the participants to investigate whether response properties reflect the input or decision. If hMT+ responses reflect the input, component motion domains (selective to incoherent percept) should show grating direction stimulus-dependent changes, unlike pattern motion domains (selective to the coherent percept). This hypothesis is based on the known direction-selective nature of inputs in component motion perceptual domains versus non-selectivity in pattern motion perceptual domains. The response amplitude of pattern motion domains did not change with grating direction (consistently with their non-selective input), in contrast to what happened for the component motion domains (consistently with their selective input). However, when we analyzed relative ratio measures they mirrored perceptual interpretation. These findings are consistent with the notion that patterns of BOLD responses reflect both sensory input and perceptual read-out.
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Mapeo Encefálico , Percepción de Movimiento/fisiología , Reconocimiento Visual de Modelos/fisiología , Corteza Visual Primaria/fisiología , Adulto , Toma de Decisiones/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Corteza Visual Primaria/diagnóstico por imagen , Adulto JovenRESUMEN
Granuloma formation is a hallmark of several infectious diseases, including those caused by Mycobacterium sp These structures are composed of accumulations of inflammatory cells, and it has been shown that cytokines such as IFN-γ and TNF-α are required for granuloma assembly during M. avium infections in mice. Macrophages (MΦs) insensitive to IFN-γ (MIIG) mice have MΦs, monocytes, and dendritic cells that are unresponsive to IFN-γ. We observed that although IFN-γ-/- mice present an exacerbated infection, the same is not true for MIIG animals, where the same levels of protection as the wild-type animals were observed in the liver and partial protection in the spleen. Unlike IFN-γ-/- mice, MIIG mice still develop well-defined granulomas, suggesting that IFN-γ-mediated MΦ activation is not required for granuloma assembly. This work also shows that MIIG animals exhibit increased cell recruitment with higher CD4+ T cells numbers as well as increased IFN-γ and TNF-α expression, suggesting that TNF-α may have a role in protection and may compensate the lack of MΦ response to IFN-γ in the MIIG model. TNF-α-deficient MIIG mice (MIIG.TNF-α-/-) exhibited increased bacterial burdens when compared with MIIG mice. These results suggest that in the absence of IFN-γ signaling in MΦs, TNF-α has a protective role against M. avium.
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Interferón gamma/fisiología , Activación de Macrófagos/inmunología , Mycobacterium avium/inmunología , Factor de Necrosis Tumoral alfa/fisiología , Animales , Linfocitos T CD4-Positivos/fisiología , Granuloma/etiología , Ratones , Ratones Endogámicos C57BL , Transducción de SeñalRESUMEN
Taking into account that the industrial processing of passion fruit generates significant amounts of waste (only the peels represent 51% of the total mass of the fruit), in the present study an economic analysis was conducted to evaluate industrial line viability for pectin extraction from passion fruit peels. Knowing that absolute ethanol (99.50% purity), used in the precipitation and washing steps, has a higher cost, a simulation of extractive distillation was performed using solvents ethylene glycol and glycerol, in the software Aspen Plus v.11, being possible to recover 99.63% of ethanol for both solvents. The results of the economic evaluation showed that the process using ethylene glycol has an advantage, mainly due to its higher profitability (1.13 times higher), lower production cost (94.86% of the price using glycerol), and a lower breakeven point (around 3% smaller). The financial indicators showed profitability and attractiveness for the implementation of this processing line.
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Biotecnología/métodos , Etanol/química , Pectinas/biosíntesis , Biotecnología/economía , Brasil , Simulación por Computador , Glicol de Etileno/química , Tecnología de Alimentos , Glicerol/química , Passiflora , Pectinas/economía , Reproducibilidad de los Resultados , Riesgo , Sensibilidad y Especificidad , Programas Informáticos , Solventes/químicaRESUMEN
Hysteresis is a well-known phenomenon in physics that relates changes in a system with its prior history. It is also part of human visual experience (perceptual hysteresis), and two different neural mechanisms might explain it: persistence (a cause of positive hysteresis), which forces to keep a current percept for longer, and adaptation (a cause of negative hysteresis), which in turn favors the switch to a competing percept early on. In this study, we explore the neural correlates underlying these mechanisms and the hypothesis of their competitive balance, by combining behavioral assessment with fMRI. We used machine learning on the behavioral data to distinguish between positive and negative hysteresis, and discovered a neural correlate of persistence at a core region of the ventral attention network, the anterior insula. Our results add to the understanding of perceptual multistability and reveal a possible mechanistic explanation for the regulation of different forms of perceptual hysteresis.
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Adaptación Fisiológica/fisiología , Corteza Cerebral/fisiología , Neuroimagen Funcional , Aprendizaje Automático , Red Nerviosa/fisiología , Percepción Visual/fisiología , Adulto , Corteza Cerebral/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Percepción de Movimiento/fisiología , Red Nerviosa/diagnóstico por imagen , Adulto JovenRESUMEN
The retina may serve as putative window into neuropathology of synaptic loss in Alzheimer's disease (AD). Here, we investigated synapse-rich layers versus layers composed by nuclei/cell bodies in an early stage of AD. In addition, we examined the associations between retinal changes and molecular and structural markers of cortical damage. We recruited 20 AD patients and 17 healthy controls (HC). Combining optical coherence tomography (OCT), magnetic resonance (MR), and positron emission tomography (PET) imaging, we measured retinal and primary visual cortex (V1) thicknesses, along with V1 amyloid ß (Aß) retention ([11C]-PiB PET tracer) and neuroinflammation ([11C]-PK11195 PET tracer). We found that V1 showed increased amyloid-binding potential, in the absence of neuroinflammation. Although thickness changes were still absent, we identified a positive association between the synapse-rich inner plexiform layer (IPL) and V1 in AD. This retinocortical interplay might reflect changes in synaptic function resulting from Aß deposition, contributing to early visual loss.
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Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Sustancia Gris/patología , Retina/patología , Sinapsis/patología , Corteza Visual/patología , Anciano , Femenino , Sustancia Gris/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Retina/metabolismo , Sinapsis/metabolismo , Corteza Visual/metabolismoRESUMEN
Martins, RS, Girouard, P, Elliott, E, and Mekary, S. Physiological responses of a jaw repositioning custom-made mouthguard on airway and their effects on athletic performance. J Strength Cond Res 34(2): 422-429, 2020-Advanced dental techniques such as jaw-repositioning have shown to increase lower body muscular power such as vertical jump, but its effects on acceleration and speed have not been studied. Similarly, jaw repositioning is commonly used to increase airways volume and ventilation in a special population (i.e., obstructive sleep apnea); however, its ergogenic effects on aerobic performance have yet not been studied. The purpose of the cross-over study was to investigate the effects of a jaw-repositioning custom-made mouthguard (JCM) on volumetric changes in airway and jaw position and determine the effects this may have on aerobic and anaerobic performance. Results indicated that jaw-repositioning custom-made mouthguard may have an ergogenic effect on performance. The JCM condition showed an increase of 13% in upper airway volume (p = 0.04), 10% in upper airway width (p = 0.004), 7% in ventilation (p = 0.006), 5% in maximal aerobic power (p = 0.003), 4% in time to exhaustion (p = 0.03), 3% in vertical jump (p = 0.03), 2% in broad jump (p = 0.009), and a decrease of 4% in 20-m (p = 0.04) and 2% in 40-m (p = 0.001) sprint times. This is the first study to demonstrate a significant link between jaw repositioning, airway volumetric change, and performance enhancement in both aerobic and anaerobic performances. The results of this study may lead to a change in culture for the use of mouthguards in different sports applications, from high orofacial injury risk sports to other sports, specifically for ergogenic enhancement.
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Rendimiento Atlético/fisiología , Maxilares/fisiología , Protectores Bucales , Mecánica Respiratoria/fisiología , Estudios Cruzados , Humanos , Masculino , Respiración , Pruebas de Función Respiratoria , Adulto JovenRESUMEN
The expansion of overhead power lines worldwide challenges companies of energy transmission and distribution, regulators and environmental consultants, among other stakeholders, to effectively mitigate their negative impacts on wildlife. Wire-marking is currently the most widespread and recommended measure to reduce bird collisions with these infrastructures. Nevertheless, and despite its importance for a bird-friendly development of energy projects, there is still much uncertainty about what explains wire-marking effectiveness. We performed an extensive literature review and meta-analysis to evaluate the overall effectiveness of wire-marking in reducing bird collisions with power lines, including the possible influencing factors of power line voltage, habitat and type of device. We gathered data from 35 field studies across the world (which included 66 trials) assessing the effectiveness of wire-marking based on regular carcass searches beneath power lines. Overall, wire-marking reduced bird collisions with power lines by half (50.4%; 95% Confidence Interval Estimate: 40.4-58.8%), although this estimate of effectiveness is lower than the one reported in a meta-analysis performed in 2011. Despite the effort to include both peer-reviewed and grey literature studies in the present meta-analysis, the risk of publication bias could not be entirely excluded and may be still overestimating the true overall effect of wire-marking. High heterogeneity among the study outcomes hindered the power to detect clear moderating effects, with none of explanatory variables being statistically significant. Large between-study heterogeneity is (to some extent) explained by the variety of anti-collision devices available, wire-marking intensities used and ecological circumstances in which the experiments were carried out. Nonetheless, it may be also related to within-study methodological biases and reporting gaps in the existing field studies. Robust experimental designs (ideally using Before-After-Control-Impact approaches), comprehensive reporting of results and broad dissemination of study findings are needed to increase the statistical power of future meta-analyses. Ways to achieve these improvements in field studies are presented in detail. Their inclusion in future meta-analyses will increase the knowledge on the drivers of wire-marking effectiveness, which is critical to better inform decision-making processes and environmental management plans.
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Animales Salvajes , Aves , Animales , EcosistemaRESUMEN
Visual adaptation describes the processes by which the visual system alters its operating properties in response to changes in the environment. It is one of the mechanisms controlling visual perceptual bistability - when two perceptual solutions are available - by controlling the duration of each percept. Moving plaids are an example of such ambiguity. They can be perceived as two surfaces sliding incoherently over each other or as a single coherent surface. Here, we investigated, using fMRI, whether activity in the human motion complex (hMT+), a region tightly related to the perceptual integration of visual motion, is modulated by distinct forms of visual adaptation to coherent or incoherent perception of moving plaids. Our hypothesis is that exposure to global coherent or incoherent moving stimuli leads to different levels of measurable adaptation, reflected in hMT+ activity. We found that the strength of the measured visual adaptation effect depended on whether subjects integrated (coherent percept) or segregated (incoherent percept) surface motion signals. Visual motion adaptation was significant both for coherent motion and globally incoherent surface motion. Although not as strong as to the coherent percept, visual adaptation due to the incoherent percept also affects hMT+. This shows that adaptation can contribute to regulate percept duration during visual bistability, with distinct weights, depending on the type of percept. Our findings suggest a link between bistability and adaptation mechanisms, both due to coherent and incoherent motion percepts, but in an asymmetric manner. These asymmetric adaptation weights have strong implications in models of perceptual decision and may explain asymmetry of perceptual interpretation periods.
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Adaptación Fisiológica/fisiología , Percepción de Movimiento/fisiología , Corteza Visual/fisiología , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Estimulación LuminosaRESUMEN
In vision, perceptual features are processed in several regions distributed across the brain. Yet, the brain achieves a coherent perception of visual scenes and objects through integration of these features, which are encoded in spatially segregated brain areas. How the brain seamlessly achieves this accurate integration is currently unknown and is referred to as the "binding problem." Among the proposed mechanisms meant to resolve the binding problem, the binding-by-synchrony hypothesis proposes that binding is carried out by the synchronization of distant neuronal assemblies. This study aimed at providing a critical test to the binding-by-synchrony hypothesis by evaluating long-range connectivity using EEG during a motion integration visual task that entails binding across hemispheres. Our results show that large-scale perceptual binding is not associated with long-range interhemispheric gamma synchrony. However, distinct perceptual interpretations were found to correlate with changes in beta power. Increased beta activity was observed during binding under ambiguous conditions and originates mainly from parietal regions. These findings reveal that the visual experience of binding can be identified by distinct signatures of oscillatory activity, regardless of long-range gamma synchrony, suggesting that such type of synchrony does not underlie perceptual binding.
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Ritmo beta/fisiología , Encéfalo/fisiología , Lateralidad Funcional/fisiología , Ritmo Gamma/fisiología , Percepción de Movimiento/fisiología , Adulto , Electroencefalografía , Procesamiento Automatizado de Datos , Femenino , Humanos , Masculino , Movimiento (Física) , Estimulación Luminosa , Análisis Espectral , Factores de Tiempo , Adulto JovenRESUMEN
It remains an open question whether long-range disambiguation of ambiguous surface motion can be achieved in early visual cortex or instead in higher level regions, which concerns object/surface segmentation/integration mechanisms. We used a bistable moving stimulus that can be perceived as a pattern comprehending both visual hemi-fields moving coherently downward or as two widely segregated nonoverlapping component objects (in each visual hemi-field) moving separately inward. This paradigm requires long-range integration across the vertical meridian leading to interhemispheric binding. Our fMRI study (n = 30) revealed a close relation between activity in hMT+ and perceptual switches involving interhemispheric segregation/integration of motion signals, crucially under nonlocal conditions where components do not overlap and belong to distinct hemispheres. Higher signal changes were found in hMT+ in response to spatially segregated component (incoherent) percepts than to pattern (coherent) percepts. This did not occur in early visual cortex, unlike apparent motion, which does not entail surface segmentation. We also identified a role for top-down mechanisms in state transitions. Deconvolution analysis of switch-related changes revealed prefrontal, insula, and cingulate areas, with the right superior parietal lobule (SPL) being particularly involved. We observed that directed influences could emerge either from left or right hMT+ during bistable motion integration/segregation. SPL also exhibited significant directed functional connectivity with hMT+, during perceptual state maintenance (Granger causality analysis). Our results suggest that long-range interhemispheric binding of ambiguous motion representations mainly reflect bottom-up processes from hMT+ during perceptual state maintenance. In contrast, state transitions maybe influenced by high-level regions such as the SPL. Hum Brain Mapp 38:4882-4897, 2017. © 2017 Wiley Periodicals, Inc.
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Lateralidad Funcional/fisiología , Percepción de Movimiento/fisiología , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/fisiología , Adulto , Mapeo Encefálico/métodos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Modelos Estadísticos , Estimulación Luminosa/métodosRESUMEN
Taxonomical analyses were performed on strain CPA58T, a novel isolate obtained from surface-sterilized aboveground tissues of the halophyte Halimione portulacoides, collected from a salt marsh in Ria de Aveiro, Portugal. The strain was Gram-stain-negative, rod-shaped, oxidase-negative and catalase-positive. Optimal growth was observed at 26 °C, at pH 6-8 and in the presence of 2 to 3â% (w/v) NaCl. Phylogenetic analyses, based on the 16S rRNA gene sequence, showed that strain CPA58T belongs to the genus Zunongwangia, with highest sequence similarities to both Zunongwangia profunda SM-A87T and Zunongwangia mangrovi P2E16T (96.5â%), followed by Zunongwangia atlantica 22II14-10F7T (95.9â%). The principal fatty acids were iso-C15â:â0, summed feature 3 (C16â:â1ω7c and/or iso-C15â:â0 2-OH) and iso-C17â:â0 3-OH. The major respiratory quinone was MK-6 and the DNA G+C content was 35.1 mol%. Phylogenetic and chemotaxonomic analyses clearly placed strain CPA58T in the genus Zunongwangia. However, 16S rRNA gene sequence analysis showed that the threshold for same species relatedness was not surpassed, and biochemical tests revealed diagnostic characteristics that differentiated this strain from other type strains of species of the genus Zunongwangia. Overall, the analyses showed that strain CPA58T represents a novel species within the genus Zunongwangia, for which the name Zunongwangia endophytica sp. nov. is proposed, with the type strain CPA58T (=CECT 9128T=LMG 29517T).
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Amaranthaceae/microbiología , Flavobacteriaceae/clasificación , Filogenia , Plantas Tolerantes a la Sal/microbiología , Humedales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Endófitos/clasificación , Endófitos/genética , Endófitos/aislamiento & purificación , Ácidos Grasos/química , Flavobacteriaceae/genética , Flavobacteriaceae/aislamiento & purificación , Portugal , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
Two Gram-negative, rod-shaped, motile bacterial strains, named CPA5T and BR75T, were isolated from the halophyte Halimione portulacoides. Both presented optimum growth at 30 °C, pH 7.0-7.5 and 1-2â% NaCl (w/v) for strain CPA5T, and pH 7.5-8.0 and 2â% NaCl (w/v) for strain BR75T. Phylogenetic analyses based on 16S rRNA gene sequences affiliated both strains to the genus Altererythrobacter. CPA5T presented highest 16S rRNA gene sequence similarity with Altererythrobacter aestuarii KYW147T (96.5â%), followed by Altererythrobacter namhicola KYW48T (95.9â%), Novosphingobium indicum H25T (95.6â%) and Altererythrobacter oceanensis Y2T (95.5â%). BR75T displayed highest similarity with Altererythrobacter marensis MSW-14T (96.5â%), followed by Altererythrobacter xinjiangensis S3-63T, Altererythrobacter luteolus SW-109T and Altererythrobacter indicus MSSRF26T (96.1â%). Neither strain contained Bacteriochlorophyll a. The main fatty acids observed for CPA5T were C17â:â1ω6c and summed features 3 (C16â:â1ω7c and/or iso-C15â:â0 2-OH) and 8 (C18â:â1 ω7c and/or C18â:â1ω6c). The latter summed feature was the dominant fatty acid observed for strain BR75T as well. The major polar lipids were phosphatidylethanolamine, unidentified phospholipids and unidentified glycolipids for both strains. The predominant ubiquinone was Q-10 for both strains, and the DNA G+C contents were 63.4 mol% and 58.3 mol% for CPA5T and BR75T, respectively. Based on phenotypic and genotypic results, both strains represent novel species belonging to the genus Altererythrobacter for which the names Altererythrobacter halimionae sp. nov. (type strain CPA5T=CECT 9130T=LMG 29519T) and Altererythrobacter endophyticus sp. nov (type strain BR75T=CECT 9129T=LMG 29518T) are proposed.
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Alphaproteobacteria/clasificación , Chenopodiaceae/microbiología , Filogenia , Humedales , Alphaproteobacteria/genética , Alphaproteobacteria/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Endófitos/clasificación , Endófitos/genética , Endófitos/aislamiento & purificación , Ácidos Grasos/química , Glucolípidos/química , Fosfolípidos/química , Portugal , ARN Ribosómico 16S/genética , Plantas Tolerantes a la Sal/microbiología , Análisis de Secuencia de ADN , Ubiquinona/químicaRESUMEN
BACKGROUND: The Associating Liver Partition and Portal Ligation for Staged Hepatectomy (ALPPS) depends on a significant inter-stages kinetic growth rate (KGR). Liver regeneration is highly energy-dependent. The metabolic adaptations in ALPPS are unknown. AIMS: i) Assess bioenergetics in both stages of ALPPS (T1 and T2) and compare them with control patients undergoing minor (miHp) and major hepatectomy (MaHp), respectively; ii) Correlate findings in ALPPS with volumetric data; iii) Investigate expression of genes involved in liver regeneration and energy metabolism. METHODS: Five patients undergoing ALPPS, five controls undergoing miHp and five undergoing MaHp. Assessment of remnant liver bioenergetics in T1, T2 and controls. Analysis of gene expression and protein content in ALPPS. RESULTS: Mitochondrial function was worsened in T1 versus miHp; and in T2 versus MaHp (p < 0.05); but improved from T1 to T2 (p < 0.05). Liver bioenergetics in T1 strongly correlated with KGR (p < 0.01). An increased expression of genes associated with liver regeneration (STAT3, ALR) and energy metabolism (PGC-1α, COX, Nampt) was found in T2 (p < 0.05). CONCLUSION: Metabolic capacity in ALPPS is worse than in controls, improves between stages and correlates with volumetric growth. Bioenergetic adaptations in ALPPS could serve as surrogate markers of liver reserve and as target for energetic conditioning.