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1.
Neuroimage ; 276: 120200, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37245560

RESUMEN

Anticipating social stress evokes strong reactions in the organism, including interoceptive modulations. However, evidence for this claim comes from behavioral studies, often with inconsistent results, and relates almost solely to the reactive and recovery phase of social stress exposure. Here, we adopted an allostatic-interoceptive predictive coding framework to study interoceptive and exteroceptive anticipatory brain responses using a social rejection task. We analyzed the heart-evoked potential (HEP) and task-related oscillatory activity of 58 adolescents via scalp EEG, and 385 human intracranial recordings of three patients with intractable epilepsy. We found that anticipatory interoceptive signals increased in the face of unexpected social outcomes, reflected in larger negative HEP modulations. Such signals emerged from key brain allostatic-interoceptive network hubs, as shown by intracranial recordings. Exteroceptive signals were characterized by early activity between 1-15 Hz across conditions, and modulated by the probabilistic anticipation of reward-related outcomes, observed over distributed brain regions. Our findings suggest that the anticipation of a social outcome is characterized by allostatic-interoceptive modulations that prepare the organism for possible rejection. These results inform our understanding of interoceptive processing and constrain neurobiological models of social stress.


Asunto(s)
Interocepción , Estatus Social , Adolescente , Humanos , Encéfalo/fisiología , Potenciales Evocados/fisiología , Electroencefalografía , Corazón , Interocepción/fisiología
2.
Neuroendocrinology ; 113(6): 657-666, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36693324

RESUMEN

INTRODUCTION: It is estimated that 30-40% of patients with apparently sporadic pheochromocytomas (PHEOs) have an inherited predisposition syndrome. The aim of our study was to develop a predictive model of hereditary PHEO based on the clinical, hormonal, and radiological features present at the diagnosis of patients with PHEOs. METHODS: A retrospective multicenter cohort study of patients with PHEOs with available genetic study from 18 tertiary hospitals. Clinical, biochemical, and radiological features were used to build a multivariate logistic regression model. The estimation of all possible equations was used to select the model with the best diagnostic accuracy (lower Akaike index). RESULTS: A total of 245 patients were included: 169 (69.0%) patients with sporadic PHEOs and 76 (31%) with hereditary PHEOs. The parsimonious predictive model with the highest diagnostic accuracy for the prediction of hereditary PHEO combined the variables age, non-cardiovascular disease, urinary norepinephrine levels, and tumor size. The area under the ROC curve of this model was 0.800 (0.705-0.887). Based on the predictive model, the probability of hereditary PHEO in patients older than 60 years with cardiovascular disease, high levels of urinary norepinephrine and unilateral PHEOs >60 mm was <2%. And if the age was above 80 years, lower than 1%. The probability of sporadic PHEO linearly increased with age (MH Test for linear Trend: χ2 (1) = 30.05; p < 0.001). CONCLUSION: In certain populations such as old patients with cardiovascular disease, with high levels of urinary norepinephrine and large tumors in which the probability of hereditary PHEO is very low, genetic testing could be avoided in the absence of specific suspicion.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales , Feocromocitoma , Humanos , Anciano de 80 o más Años , Feocromocitoma/diagnóstico , Feocromocitoma/genética , Feocromocitoma/patología , Estudios de Cohortes , Pruebas Genéticas , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Neoplasias de las Glándulas Suprarrenales/genética , Neoplasias de las Glándulas Suprarrenales/patología , Norepinefrina
3.
Biofouling ; 39(5): 483-501, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37394974

RESUMEN

In order to build an efficient closed-photobioreactor (PBR) in which biofouling formation is avoided, a non-toxic coating with high transparency is required, which can be applied to the interior surface of the PBR walls. Nowadays, amphiphilic copolymers are being used to inhibit microorganism adhesion, so poly(dimethylsiloxane)-based coatings mixed with poly(ethylene glycol)-based copolymers could be a good option. The 7 poly(dimethylsiloxane)-based coatings tested in this work contained 4% w/w of poly(ethylene glycol)-based copolymers. All were a good alternative to glass because they presented lower cell adhesion. However, the DBE-311 copolymer proved the best option due to its very low cell adhesion and high transmittance. Furthermore, XDLVO theory indicates that these coatings should have no cell adhesion at time 0 since they create a very high-energy barrier that microalgae cells cannot overcome. Nevertheless, this theory also shows that their surface properties change over time, making cell adhesion possible on all coatings after 8 months of immersion. The theory is useful in explaining the interaction forces between the surface and microalgae cells at any moment in time, but it should be complemented with models to predict the conditioning film formation and the contribution of the PBR's fluid dynamics over time.


Asunto(s)
Incrustaciones Biológicas , Incrustaciones Biológicas/prevención & control , Fotobiorreactores , Biopelículas , Polietilenglicoles/farmacología , Polímeros/farmacología , Propiedades de Superficie
4.
Biofouling ; 38(5): 507-520, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35729852

RESUMEN

This work analyses the adhesion of flagellated microalgae to seven surfaces that have different water adhesion tension characteristics. Chlamydomonas reinhardtii and Isochrysis galbana, were cultivated in batch and fed-batch mode at four nitrogen/phosphorus (N/P) ratios (from 1.29 to 70) and subjected to four irradiance levels (50, 100, 200 and 400 µE·s-1·m-2) at 23 °C. Cell adhesion was greater in C. reinhardtii and a higher biomass concentration was obtained for this strain, reaching 2 g·L-1 compared to 1 g·L-1 for I. galbana. The adhesion of cells and exopolymeric substances was measured upon the batch and the first fed-batch reaching the stationary growth phase, observing a direct correlation between them and inversely to biomass generation in the cultures. The protein adhesion data for the different materials are comparable to those for cell adhesion coinciding with minimums of Baier's theory and Vogler. It is observed displacements in the curves as a function of the irradiance level.


Asunto(s)
Incrustaciones Biológicas , Microalgas , Biopelículas , Biomasa , Nitrógeno , Fotobiorreactores
5.
Sensors (Basel) ; 22(11)2022 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-35684734

RESUMEN

Pisum sativum L. ssp. arvense, is colloquially called tirabeque or mangetout because it is eaten whole; its pods are recognized as a delicatessen in cooking due to its crunch on the palate and high sweetness. Furthermore, this legume is an important source of protein and antioxidant compounds. Quality control in this species requires the analysis of a large number of samples using costly and laborious conventional methods. For this reason, a non-chemical and rapid technique as near-infrared reflectance spectroscopy (NIRS) was explored to determine its physicochemical quality (color, firmness, total soluble solids, pH, total polyphenols, ascorbic acid and protein content). Pod samples from different cultivars and grown under different fertigation treatments were added to the NIRS analysis to increase spectral and chemical variability in the calibration set. Modified partial least squares regression was used for obtaining the calibration models of these parameters. The coefficients of determination in the external validation ranged from 0.50 to 0.88. The RPD (standard deviation to standard error of prediction ratio) and RER (standard deviation to range) were variable for quality parameters and showed values that were characteristic of equations suitable for quantitative prediction and screening purposes, except for the total soluble solid calibration model.


Asunto(s)
Pisum sativum , Espectroscopía Infrarroja Corta , Calibración , Análisis de los Mínimos Cuadrados , Espectroscopía Infrarroja Corta/métodos
6.
Int J Mol Sci ; 23(22)2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36430401

RESUMEN

An improved method that allows the robust characterization of surfaces is necessary to accurately predict the biofouling formation on construction materials of photobioreactors (PBR). Exopolymeric substances (EPS), such as proteins and polysaccharides, have been demonstrated to present a similar behavior to cells in terms of surface adhesion. In this work, these EPS were used to optimize parameters, such as EPS concentration or adsorption time, to evaluate accurately the adsorption capacity of surfaces and, with it, predict the biofouling formation in contact with microalgae cultures. Once the method was optimized, the characterization of seven commercial polymeric surfaces was submitted to different abrasive particles sizes, which modified the roughness of the samples, as well as protein and polysaccharide lawns, which were prepared and carried out in order to evaluate the characteristics of these substances. The characterization consisted of the determination of surface free energy, water adhesion tension, and critical tension determined from the measurement of the contact angle, roughness, surface zeta potential, and the EPS adhesion capacity of each material. This will be useful to understand the behavior of the surface in the function of its characteristics and the interaction with the solutions of EPS, concluding that the hydrophobic and smooth surfaces present good anti-biofouling characteristics.


Asunto(s)
Incrustaciones Biológicas , Microalgas , Fotobiorreactores , Adsorción , Matriz Extracelular de Sustancias Poliméricas , Incrustaciones Biológicas/prevención & control
7.
Eur J Clin Microbiol Infect Dis ; 40(11): 2411-2419, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33864153

RESUMEN

PURPOSE: To evaluate preoperative asymptomatic bacteriuria (ASB) treatment to reduce early-periprosthetic joint infections (early-PJIs) after hip hemiarthroplasty (HHA) for fracture. METHODS: Open-label, multicenter RCT comparing fosfomycin-trometamol versus no intervention with a parallel follow-up cohort without ASB. PRIMARY OUTCOME: early-PJI after HHA. RESULTS: Five hundred ninety-four patients enrolled (mean age 84.3); 152(25%) with ASB (77 treated with fosfomycin-trometamol/75 controls) and 442(75%) without. Despite the study closed without the intended sample size, ASB was not predictive of early-PJI (OR: 1.06 [95%CI: 0.33-3.38]), and its treatment did not modify early-PJI incidence (OR: 1.03 [95%CI: 0.15-7.10]). CONCLUSIONS: Neither preoperative ASB nor its treatment appears to be risk factors of early-PJI after HHA. ClinicalTrials.gov Identifier: Eudra CT 2016-001108-47.


Asunto(s)
Artroplastia de Reemplazo de Cadera/efectos adversos , Bacteriuria/microbiología , Artropatías/microbiología , Infecciones Relacionadas con Prótesis/microbiología , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Infecciones Asintomáticas/terapia , Bacteriuria/tratamiento farmacológico , Bacteriuria/etiología , Femenino , Fosfomicina/uso terapéutico , Humanos , Artropatías/tratamiento farmacológico , Artropatías/etiología , Masculino , Infecciones Relacionadas con Prótesis/tratamiento farmacológico , Infecciones Relacionadas con Prótesis/etiología , Trometamina/uso terapéutico
8.
CNS Spectr ; : 1-9, 2021 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-34121647

RESUMEN

BACKGROUND: Few studies have analyzed compulsive buying behavior in relation to a specific product. Smartphones are hugely popular products today, especially among young people. These two aspects have motivated this research into the compulsive buying behavior of Smartphones by university students. METHODS: To study this behavior, the main features that differentiate compulsive buyers from those that are not are analyzed, and their risk profiles are obtained through a discrete choice model. RESULTS: Sociodemographic features that define buyers with the greatest propensity to compulsiveness are younger age, longer time spent daily using social networks, higher spending on the acquisition of Smartphones and having owned a greater number of these devices. These buyers also show shopping addiction and greater feelings of guilt after the purchase as well as more positive and negative affective states when purchasing Smartphones. CONCLUSIONS: This analysis not only determines the characteristics that define young individuals with a tendency toward compulsiveness in Smartphone purchases, but also contributes to quantifying the probability of having this tendency.

9.
Cereb Cortex ; 30(8): 4563-4580, 2020 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-32219312

RESUMEN

At any given moment, we experience a perceptual scene as a single whole and yet we may distinguish a variety of objects within it. This phenomenon instantiates two properties of conscious perception: integration and differentiation. Integration is the property of experiencing a collection of objects as a unitary percept and differentiation is the property of experiencing these objects as distinct from each other. Here, we evaluated the neural information dynamics underlying integration and differentiation of perceptual contents during bistable perception. Participants listened to a sequence of tones (auditory bistable stimuli) experienced either as a single stream (perceptual integration) or as two parallel streams (perceptual differentiation) of sounds. We computed neurophysiological indices of information integration and information differentiation with electroencephalographic and intracranial recordings. When perceptual alternations were endogenously driven, the integrated percept was associated with an increase in neural information integration and a decrease in neural differentiation across frontoparietal regions, whereas the opposite pattern was observed for the differentiated percept. However, when perception was exogenously driven by a change in the sound stream (no bistability), neural oscillatory power distinguished between percepts but information measures did not. We demonstrate that perceptual integration and differentiation can be mapped to theoretically motivated neural information signatures, suggesting a direct relationship between phenomenology and neurophysiology.


Asunto(s)
Percepción Auditiva/fisiología , Encéfalo/fisiología , Estimulación Acústica , Electroencefalografía , Femenino , Humanos , Masculino , Adulto Joven
10.
Sensors (Basel) ; 21(6)2021 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-33808978

RESUMEN

Liver transplantation is the only curative treatment option in patients diagnosed with end-stage liver disease. The low availability of organs demands an accurate selection procedure based on histological analysis, in order to evaluate the allograft. This assessment, traditionally carried out by a pathologist, is not exempt from subjectivity. In this sense, new tools based on machine learning and artificial vision are continuously being developed for the analysis of medical images of different typologies. Accordingly, in this work, we develop a computer vision-based application for the fast and automatic objective quantification of macrovesicular steatosis in histopathological liver section slides stained with Sudan stain. For this purpose, digital microscopy images were used to obtain thousands of feature vectors based on the RGB and CIE L*a*b* pixel values. These vectors, under a supervised process, were labelled as fat vacuole or non-fat vacuole, and a set of classifiers based on different algorithms were trained, accordingly. The results obtained showed an overall high accuracy for all classifiers (>0.99) with a sensitivity between 0.844 and 1, together with a specificity >0.99. In relation to their speed when classifying images, KNN and Naïve Bayes were substantially faster than other classification algorithms. Sudan stain is a convenient technique for evaluating ME in pre-transplant liver biopsies, providing reliable contrast and facilitating fast and accurate quantification through the machine learning algorithms tested.


Asunto(s)
Trasplante de Hígado , Algoritmos , Teorema de Bayes , Secciones por Congelación , Humanos , Aprendizaje Automático , Sudán
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