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1.
Ann Neurol ; 96(1): 46-60, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38624158

RESUMEN

OBJECTIVE: Recent evidence shows that during slow-wave sleep (SWS), the brain is cleared from potentially toxic metabolites, such as the amyloid-beta protein. Poor sleep or elevated cortisol levels can worsen amyloid-beta clearance, potentially leading to the formation of amyloid plaques, a neuropathological hallmark of Alzheimer disease. Here, we explored how nocturnal neural and endocrine activity affects amyloid-beta fluctuations in the peripheral blood. METHODS: We acquired simultaneous polysomnography and all-night blood sampling in 60 healthy volunteers aged 20-68 years. Nocturnal plasma concentrations of amyloid-beta-40, amyloid-beta-42, cortisol, and growth hormone were assessed every 20 minutes. Amyloid-beta fluctuations were modeled with sleep stages, (non)oscillatory power, and hormones as predictors while controlling for age and participant-specific random effects. RESULTS: Amyloid-beta-40 and amyloid-beta-42 levels correlated positively with growth hormone concentrations, SWS proportion, and slow-wave (0.3-4Hz) oscillatory and high-band (30-48Hz) nonoscillatory power, but negatively with cortisol concentrations and rapid eye movement sleep (REM) proportion measured 40-100 minutes previously (all t values > |3|, p values < 0.003). Older participants showed higher amyloid-beta-40 levels. INTERPRETATION: Slow-wave oscillations are associated with higher plasma amyloid-beta levels, whereas REM sleep is related to decreased amyloid-beta plasma levels, possibly representing changes in central amyloid-beta production or clearance. Strong associations between cortisol, growth hormone, and amyloid-beta presumably reflect the sleep-regulating role of the corresponding releasing hormones. A positive association between age and amyloid-beta-40 may indicate that peripheral clearance becomes less efficient with age. ANN NEUROL 2024;96:46-60.


Asunto(s)
Péptidos beta-Amiloides , Polisomnografía , Sueño REM , Sueño de Onda Lenta , Humanos , Persona de Mediana Edad , Péptidos beta-Amiloides/sangre , Péptidos beta-Amiloides/metabolismo , Adulto , Masculino , Anciano , Femenino , Sueño de Onda Lenta/fisiología , Adulto Joven , Sueño REM/fisiología , Hidrocortisona/sangre , Fragmentos de Péptidos/sangre
2.
Forensic Sci Int ; 337: 111372, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35780517

RESUMEN

The process of linking an offender to a crime scene via their fingerprints has historically required significant human effort to compare latent fingerprints recovered from the scene with known fingerprints of a suspect. Increasing the speed of such comparisons, whilst maintaining accuracy and reliability and minimising error, is crucial for providing rapid intelligence to police investigators. One major opportunity for streamlining fingerprint examination is the adaptation of 'lights-out' technology to the comparison and matching of latent fingerprints. Here, we review the development, trial and validation process undertaken by the Queensland Police Service (QPS), Australia, to support implementation of a lights-out latent (LOL) workflow for automated latent fingerprint searching that is fully integrated with the existing case management systems. Targeted trials were undertaken using random selections of previously identified latent fingerprints that were searched using the LOL workflow against a local 10-print database. The results suggested that the LOL workflow could identify up to 44% of latent fingerprints with minimal human intervention and supported its implementation for all latent fingerprint comparisons in QPS casework. Review of LOL casework comparison outcomes for 2019 revealed that LOL-based identifications contributed approximately one quarter of all fingerprint identifications. Several procedural and technical factors that influenced the speed and efficiency of the LOL workflow are discussed, along with opportunities for improvement and future validation as an expert system.


Asunto(s)
Dermatoglifia , Bases de Datos Factuales , Humanos , Queensland , Reproducibilidad de los Resultados , Flujo de Trabajo
3.
PLoS One ; 16(12): e0260954, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34932587

RESUMEN

Elimination of the binding of immunoglobulin Fc to Fc gamma receptors (FcγR) is highly desirable for the avoidance of unwanted inflammatory responses to therapeutic antibodies and fusion proteins. Many different approaches have been described in the literature but none of them completely eliminates binding to all of the Fcγ receptors. Here we describe a set of novel variants having specific amino acid substitutions in the Fc region at L234 and L235 combined with the substitution G236R. They show no detectable binding to Fcγ receptors or to C1q, are inactive in functional cell-based assays and do not elicit inflammatory cytokine responses. Meanwhile, binding to FcRn, manufacturability, stability and potential for immunogenicity are unaffected. These variants have the potential to improve the safety and efficacy of therapeutic antibodies and Fc fusion proteins.


Asunto(s)
Citotoxicidad Celular Dependiente de Anticuerpos , Complemento C1q/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Fragmentos Fc de Inmunoglobulinas/metabolismo , Inmunoglobulina G/metabolismo , Receptores Fc/metabolismo , Receptores de IgG/metabolismo , Sustitución de Aminoácidos , Afinidad de Anticuerpos , Complemento C1q/genética , Complemento C1q/inmunología , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Fragmentos Fc de Inmunoglobulinas/genética , Fragmentos Fc de Inmunoglobulinas/inmunología , Inmunoglobulina G/genética , Inmunoglobulina G/inmunología , Unión Proteica , Ingeniería de Proteínas , Receptores Fc/genética , Receptores Fc/inmunología , Receptores de IgG/genética , Receptores de IgG/inmunología
4.
Br J Nutr ; : 1-18, 2021 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-34505561

RESUMEN

Food manufacturers are under increasing pressure to limit the amount of free sugars in their products. Many have reformulated products to replace sucrose, glucose and fructose with alternative sweeteners, but some of these have been associated with additional health concerns. Rare sugars are 'monosaccharides and their derivatives that hardly exist in nature', and there is increasing evidence that they could have health benefits. This review aimed to scope the existing literature in order to identify the most commonly researched rare sugars, to ascertain their proposed health benefits, mechanisms of action and potential uses and to highlight knowledge gaps. A process of iterative database searching identified fifty-five relevant articles. The reported effects of rare sugars were noted, along with details of the research methodologies conducted. Our results indicated that the most common rare sugars investigated are d-psicose and d-tagatose, with the potential health benefits divided into three topics: glycaemic control, body composition and CVD. All the rare sugars investigated have the potential to suppress postprandial elevation of blood glucose and improve glycaemic control in both human and animal models. Some animal studies have suggested that certain rare sugars may also improve lipid profiles, alter the gut microbiome and reduce pro-inflammatory cytokine expression. The present review demonstrates that rare sugars could play a role in reducing the development of obesity, type 2 diabetes and/or CVD. However, understanding of the mechanisms by which rare sugars may exert their effects is limited, and their effectiveness when used in reformulated products is unknown.

5.
J Neurosci ; 41(36): 7675-7686, 2021 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-34330775

RESUMEN

A key aspect of conceptual knowledge is that it can be flexibly applied at different levels of abstraction, implying a hierarchical organization. It is yet unclear how this hierarchical structure is acquired and represented in the brain. Here we investigate the computations underlying the acquisition and representation of the hierarchical structure of conceptual knowledge in the hippocampal-prefrontal system of 32 human participants (22 females). We assessed the hierarchical nature of learning during a novel tree-like categorization task via computational model comparisons. The winning model allowed to extract and quantify estimates for accumulation and updating of hierarchical compared with single-feature-based concepts from behavior. We find that mPFC tracks accumulation of hierarchical conceptual knowledge over time, and mPFC and hippocampus both support trial-to-trial updating. As a function of those learning parameters, mPFC and hippocampus further show connectivity changes to rostro-lateral PFC, which ultimately represented the hierarchical structure of the concept in the final stages of learning. Our results suggest that mPFC and hippocampus support the integration of accumulated evidence and instantaneous updates into hierarchical concept representations in rostro-lateral PFC.SIGNIFICANCE STATEMENT A hallmark of human cognition is the flexible use of conceptual knowledge at different levels of abstraction, ranging from a coarse category level to a fine-grained subcategory level. While previous work probed the representational geometry of long-term category knowledge, it is unclear how this hierarchical structure inherent to conceptual knowledge is acquired and represented. By combining a novel hierarchical concept learning task with computational modeling of categorization behavior and concurrent fMRI, we differentiate the roles of key concept learning regions in hippocampus and PFC in learning computations and the representation of a hierarchical category structure.


Asunto(s)
Formación de Concepto/fisiología , Hipocampo/diagnóstico por imagen , Aprendizaje/fisiología , Corteza Prefrontal/diagnóstico por imagen , Adulto , Mapeo Encefálico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Solución de Problemas/fisiología , Adulto Joven
6.
Front Psychol ; 11: 955, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32793015

RESUMEN

Words can either boost or hinder the processing of visual information, which can lead to facilitation or interference of the behavioral response. We investigated the stage (response execution or target processing) of verbal interference/facilitation in the response priming paradigm with a gender categorization task. Participants in our study were asked to judge whether the presented stimulus was a female or male face that was briefly preceded by a gender word either congruent (prime: "man," target: "man"), incongruent (prime: "woman," target: "man") or neutral (prime: "day," target: "man") with respect to the face stimulus. We investigated whether related word-picture pairs resulted in faster reaction times in comparison to the neutral word-picture pairs (facilitation) and whether unrelated word-picture pairs resulted in slower reaction times in comparison to neutral word-picture pairs (interference). We further examined whether these effects (if any) map onto response conflict or aspects of target processing. In addition, identity ("man," "woman") and associative ("tie," "dress") primes were introduced to investigate the cognitive mechanisms of semantic and Stroop-like effects in response priming (introduced respectively by associations and identity words). We analyzed responses and reaction times using the drift diffusion model to examine the effect of facilitation and/or interference as a function of the prime type. We found that regardless of prime type words introduce a facilitatory effect, which maps to the processes of visual attention and response execution.

7.
Neuropsychologia ; 146: 107560, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32679135

RESUMEN

Flexible language use requires coordinated functioning of two systems: conceptual representations and control. The interaction between the two systems can be observed when people are asked to match a word to a picture. Participants are slower and less accurate for related word-picture pairs (word: banana, picture: apple) relative to unrelated pairs (word: banjo, picture: apple). The mechanism underlying interference however is still unclear. We analyzed word-picture matching (WPM) performance of patients with stroke-induced lesions to the left-temporal (N = 5) or left-frontal cortex (N = 5) and matched controls (N = 12) using the drift diffusion model (DDM). In DDM, the process of making a decision is described as the stochastic accumulation of evidence towards a response. The parameters of the DDM model that characterize this process are decision threshold, drift rate, starting point and non-decision time, each of which bears cognitive interpretability. We compared the estimated model parameters from controls and patients to investigate the mechanisms of WPM interference. WPM performance in controls was explained by the amount of information needed to make a decision (decision threshold): a higher threshold was associated with related word-picture pairs relative to unrelated ones. No difference was found in the quality of the evidence (drift rate). This suggests an executive rather than semantic mechanism underlying WPM interference. Both patients with temporal and frontal lesions exhibited both increased drift rate and decision threshold for unrelated pairs relative to related ones. Left-frontal and temporal damage affected the computations required by WPM similarly, resulting in systematic deficits across lexical-semantic memory and executive functions. These results support a diverse but interactive role of lexical-semantic memory and semantic control mechanisms.


Asunto(s)
Simulación por Computador , Función Ejecutiva , Lóbulo Frontal/fisiopatología , Modelos Neurológicos , Semántica , Accidente Cerebrovascular/fisiopatología , Lóbulo Temporal/fisiopatología , Anciano , Femenino , Humanos , Masculino , Memoria , Persona de Mediana Edad
8.
Food Chem ; 316: 126350, 2020 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-32045819

RESUMEN

This work characterises the peptide and protein profiles of Theobroma cacao beans of the genotype IMC 67 at different fermentation stages, using the Styrofoam-box fermentation method and employing UHPLC-ESI MS/MS for the analysis of peptides and proteins extracted from the beans. A total of 1058 endogenous peptides were identified and quantified over four fermentation time points. The majority of these peptides were formed after 2 and 4 days of fermentation, and originated predominantly from the proteolysis of two storage proteins - vicilin and a 21 kDa albumin. The changes in the peptide profile over fermentation were subsequently evaluated, and potential markers for assessing the degree of fermentation were identified. In particular, changes of the relative abundance of the major cocoa proteins detected can be proposed as potential markers for the fermentation stage. Furthermore, PCA of both the peptidomic and proteomic data has allowed differentiation of beans at different fermentation stages.


Asunto(s)
Cacao/metabolismo , Péptidos/metabolismo , Proteómica , Albúminas/metabolismo , Reactores Biológicos , Cromatografía Líquida de Alta Presión , Fermentación , Poliestirenos , Proteínas de Almacenamiento de Semillas/metabolismo , Espectrometría de Masas en Tándem
9.
Food Chem ; 303: 125244, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31445177

RESUMEN

In this study the proteomic profiles of cocoa beans from four genotypes with different flavour profiles were analysed by bottom-up label-free UHPLC-MS/MS. From a total of 430 identified proteins, 61 proteins were found significantly differentially expressed among the four cocoa genotypes analysed with a fold change of ≥2. PCA analysis allowed clear separation of the genotypes based on their proteomic profiles. Genotype-specific abundances were recorded for proteases involved in the degradation of storage proteins and release of flavour precursors. Different genotype-specific levels of other enzymes, which generate volatiles compounds that could potentially lead to flavour-inducing compounds, were also detected. Overall, this study shows that UHPLC-MS/MS data can differentiate cocoa bean varieties.


Asunto(s)
Cacao/genética , Cacao/metabolismo , Cromatografía Líquida de Alta Presión , Genotipo , Proteómica , Espectrometría de Masas en Tándem , Gusto
10.
Brain ; 142(10): 3217-3229, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31560064

RESUMEN

The generation of hierarchical structures is central to language, music and complex action. Understanding this capacity and its potential impairments requires mapping its underlying cognitive processes to the respective neuronal underpinnings. In language, left inferior frontal gyrus and left posterior temporal cortex (superior temporal sulcus/middle temporal gyrus) are considered hubs for syntactic processing. However, it is unclear whether these regions support computations specific to language or more generally support analyses of hierarchical structure. Here, we address this issue by investigating hierarchical processing in a non-linguistic task. We test the ability to represent recursive hierarchical embedding in the visual domain by contrasting a recursion task with an iteration task. The recursion task requires participants to correctly identify continuations of a hierarchy generating procedure, while the iteration task applies a serial procedure that does not generate new hierarchical levels. In a lesion-based approach, we asked 44 patients with left hemispheric chronic brain lesion to perform recursion and iteration tasks. We modelled accuracies and response times with a drift diffusion model and for each participant obtained parametric estimates for the velocity of information accumulation (drift rates) and for the amount of information accumulated before a decision (boundary separation). We then used these estimates in lesion-behaviour analyses to investigate how brain lesions affect specific aspects of recursive hierarchical embedding. We found that lesions in the posterior temporal cortex decreased drift rate in recursive hierarchical embedding, suggesting an impaired process of rule extraction from recursive structures. Moreover, lesions in inferior temporal gyrus decreased boundary separation. The latter finding does not survive conservative correction but suggests a shift in the decision criterion. As patients also participated in a grammar comprehension experiment, we performed explorative correlation-analyses and found that visual and linguistic recursive hierarchical embedding accuracies are correlated when the latter is instantiated as sentences with two nested embedding levels. While the roles of the inferior temporal gyrus and posterior temporal cortex in linguistic processes are well established, here we show that posterior temporal cortex lesions slow information accumulation (drift rate) in the visual domain. This suggests that posterior temporal cortex is essential to acquire the (knowledge) representations necessary to parse recursive hierarchical embedding in visual structures, a finding mimicking language acquisition in young children. On the contrary, inferior frontal gyrus lesions seem to affect recursive hierarchical embedding processing by interfering with more general cognitive control (boundary separation). This interesting separation of roles, rooted on a domain-general taxonomy, raises the question of whether such cognitive framing is also applicable to other domains.


Asunto(s)
Cognición/fisiología , Comprensión/fisiología , Corteza Prefrontal/fisiología , Adulto , Anciano , Encéfalo/fisiología , Mapeo Encefálico/métodos , Toma de Decisiones , Femenino , Humanos , Lenguaje , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Música , Red Nerviosa/fisiología , Desempeño Psicomotor/fisiología , Lóbulo Temporal/fisiología , Percepción Visual/fisiología
11.
J Abnorm Child Psychol ; 47(3): 543-555, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-29946886

RESUMEN

This study aimed to disentangle the effects of Mild-to-Borderline Intellectual Disability (MBID) and Behavior Disorders (BD)on risk taking in circumstances where peer influence was absent or present. We studied 319 adolescents in four groups: MBID-only, MBID+BD, BD-only, and typically developing controls. The Balloon Analogue Risk-Task (BART), in a solo or peer condition, was used as a proxy of real-life risk-taking. Results show a significant main effect of BART condition. Post-hoc tests indicated higher risk-taking in the peer compared to the solo condition in all groups except BD-only. Moreover, risk taking was increased in adolescents with MBID compared to adolescents without MBID, but only under peer-influence. No main or interaction effects with BD were observed. Model based decomposition of BART performance in underlying processes showed that the MBID related increase in risk-taking under peer-influence was mainly related to increased risk-taking propensity, and in the MBID-only group also to increased safety estimates and increased confidence in these safety estimates. The present study shows that risk-taking in MBID may be better explained by low intellectual functioning than by comorbid BD, and may not originate in increased risk taking per se, but may rather be related to risk-taking under peer-influence, which is a complex, multifaceted risk-taking context. Therefore, interventions to decrease risk-taking by adolescents with MBID that specifically target peer-influence may be successful.


Asunto(s)
Conducta del Adolescente/fisiología , Trastornos de la Conducta Infantil/fisiopatología , Discapacidad Intelectual/fisiopatología , Influencia de los Compañeros , Asunción de Riesgos , Adolescente , Niño , Humanos , Masculino , Índice de Severidad de la Enfermedad
12.
J Neurosci ; 38(40): 8694-8706, 2018 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-30181134

RESUMEN

Improving extinction learning is essential to optimize psychotherapy for persistent fear-related disorders. In two independent studies (both n = 24), we found that goal-directed eye movements activate a dorsal frontoparietal network and transiently deactivate the amygdala (η p2 = 0.17). Connectivity analyses revealed that this downregulation potentially engages a ventromedial prefrontal pathway known to be involved in cognitive regulation of emotion. Critically, when eye movements followed memory reactivation during extinction learning, it reduced spontaneous fear recovery 24 h later (η p2 = 0.21). Stronger amygdala deactivation furthermore predicted a stronger reduction in subsequent fear recovery after reinstatement (r = 0.39). In conclusion, we show that extinction learning can be improved with a noninvasive eye-movement intervention that triggers a transient suppression of the amygdala. Our finding that another task which taxes working memory leads to a similar amygdala suppression furthermore indicates that this effect is likely not specific to eye movements, which is in line with a large body of behavioral studies. This study contributes to the understanding of a widely used treatment for traumatic symptoms by providing a parsimonious account for how working-memory tasks and goal-directed eye movements can enhance extinction-based psychotherapy, namely through neural circuits (e.g., amygdala deactivation) similar to those that support cognitive control of emotion.SIGNIFICANCE STATEMENT Fear-related disorders represent a significant burden on individual sufferers and society. There is a high need to optimize treatment, in particular via noninvasive means. One potentially effective intervention is execution of eye movements following trauma recall. However, a neurobiological understanding of how eye movements reduce traumatic symptoms is lacking. We demonstrate that goal-directed eye-movements, like working-memory tasks, deactivate the amygdala, the core neural substrate of fear learning. Effective connectivity analyses revealed amygdala deactivation potentially engaged dorsolateral and ventromedial prefrontal pathways. When applied during safety learning, this deactivation predicts a reduction in later fear recovery. These findings provide a parsimonious and mechanistic account of how behavioral manipulations taxing working memory and suppressing amygdala activity can alter retention of emotional memories.


Asunto(s)
Amígdala del Cerebelo/fisiología , Extinción Psicológica/fisiología , Movimientos Oculares , Miedo/fisiología , Adulto , Mapeo Encefálico , Condicionamiento Clásico , Electrochoque , Femenino , Lóbulo Frontal/fisiología , Respuesta Galvánica de la Piel , Objetivos , Humanos , Imagen por Resonancia Magnética , Masculino , Memoria a Corto Plazo , Vías Nerviosas/fisiología , Lóbulo Parietal/fisiología , Adulto Joven
13.
Med J Aust ; 209(7): 306-311, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30257623

RESUMEN

OBJECTIVE: To determine whether the risk of upper gastrointestinal bleeding in patients taking low dose aspirin (≤ 325 mg/day) is increased in people with Helicobacter pylori infections. STUDY DESIGN: A systematic search for all publications since 1989 (when H. pylori was named) using search term equivalents for "upper gastrointestinal haemorrhage" and "aspirin". Articles were assessed individually for inclusion of data on H. pylori infection, as not all relevant papers were indexed with this term. Data that could be pooled were then subjected to meta-analysis, using a random effects model. DATA SOURCES: MEDLINE, Embase, Scopus, the Cochrane Library. DATA SYNTHESIS: Of 7599 retrieved publications, reports for seven case-control studies contained data suitable for meta-analysis; four were deemed high quality on the Newcastle-Ottawa scale. Upper gastrointestinal haemorrhage was more frequent in aspirin users infected with H. pylori than in those who were not (odds ratio [OR], 2.32; 95% CI, 1.25-4.33; P = 0.008). The heterogeneity of the studies was significant (Q = 19.3, P = 0.004; I2 = 68.9%, 95% CI, 31.5-85.9%), but the pooled odds ratio was similar after removing the two studies that contributed most to heterogeneity (OR, 2.34; 95% CI, 1.56-3.53; P < 0.001). The number needed to treat to prevent one bleeding event annually was estimated to be between 100 and more than 1000. CONCLUSIONS: The odds of upper gastrointestinal bleeding in patients taking low dose aspirin is about twice as great in those infected with H. pylori. Testing for and treating the infection should be considered in such patients, especially if their underlying risk of peptic ulcer bleeding is already high.


Asunto(s)
Aspirina/efectos adversos , Infecciones por Helicobacter , Úlcera Péptica Hemorrágica , Adulto , Anciano , Anciano de 80 o más Años , Aspirina/administración & dosificación , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/epidemiología , Helicobacter pylori , Humanos , Persona de Mediana Edad , Úlcera Péptica Hemorrágica/complicaciones , Úlcera Péptica Hemorrágica/epidemiología , Factores de Riesgo
14.
Sci Rep ; 8(1): 14156, 2018 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-30237542

RESUMEN

Linguistic labels are known to facilitate object recognition, yet the mechanism of this facilitation is not well understood. Previous psychophysical studies have suggested that words guide visual perception by activating information about visual object shape. Here we aimed to test this hypothesis at the neural level, and to tease apart the visual and semantic contribution of words to visual object recognition. We created a set of object pictures from two semantic categories with varying shapes, and obtained subjective ratings of their shape and category similarity. We then conducted a word-picture matching experiment, while recording participants' EEG, and tested if the shape or the category similarity between the word's referent and target picture explained the spatiotemporal pattern of the picture-evoked responses. The results show that hearing a word activates representations of its referent's shape, which interacts with the visual processing of a subsequent picture within 100 ms from its onset. Furthermore, non-visual categorical information, carried by the word, affects the visual processing at later stages. These findings advance our understanding of the interaction between language and visual perception and provide insights into how the meanings of words are represented in the brain.


Asunto(s)
Encéfalo/fisiología , Comprensión/fisiología , Potenciales Evocados Visuales/fisiología , Reconocimiento Visual de Modelos/fisiología , Adulto , Femenino , Humanos , Lenguaje , Masculino , Semántica
15.
Proteomics ; 18(3-4)2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29280563

RESUMEN

Cocoa seed storage proteins play an important role in flavour development as aroma precursors are formed from their degradation during fermentation. Major proteins in the beans of Theobroma cacao are the storage proteins belonging to the vicilin and albumin classes. Although both these classes of proteins have been extensively characterized, there is still limited information on the expression and abundance of other proteins present in cocoa beans. This work is the first attempt to characterize the whole cocoa bean proteome by nano-UHPLC-ESI MS/MS analysis using tryptic digests of cocoa bean protein extracts. The results of this analysis show that >1000 proteins could be identified using a species-specific Theobroma cacao database. The majority of the identified proteins were involved with metabolism and energy. Additionally, a significant number of the identified proteins were linked to protein synthesis and processing. Several proteins were also involved with plant response to stress conditions and defence. Albumin and vicilin storage proteins showed the highest intensity values among all detected proteins, although only seven entries were identified as storage proteins. A comparison of MS/MS data searches carried out against larger non-specific databases confirmed that using a species-specific database can increase the number of identified proteins, and at the same time reduce the number of false positives. The results of this work will be useful in developing tools that can allow the comparison of the proteomic profile of cocoa beans from different genotypes and geographic origins. Data are available via ProteomeXchange with identifier PXD005586.


Asunto(s)
Cacao/metabolismo , Cromatografía Líquida de Alta Presión/métodos , Nanotecnología/métodos , Proteoma/análisis , Proteínas de Almacenamiento de Semillas/metabolismo , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Cacao/crecimiento & desarrollo , Semillas/metabolismo
16.
Brain ; 140(5): 1231-1237, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-28122878

RESUMEN

In extensive studies with two split-brain patients we replicate the standard finding that stimuli cannot be compared across visual half-fields, indicating that each hemisphere processes information independently of the other. Yet, crucially, we show that the canonical textbook findings that a split-brain patient can only respond to stimuli in the left visual half-field with the left hand, and to stimuli in the right visual half-field with the right hand and verbally, are not universally true. Across a wide variety of tasks, split-brain patients with a complete and radiologically confirmed transection of the corpus callosum showed full awareness of presence, and well above chance-level recognition of location, orientation and identity of stimuli throughout the entire visual field, irrespective of response type (left hand, right hand, or verbally). Crucially, we used confidence ratings to assess conscious awareness. This revealed that also on high confidence trials, indicative of conscious perception, response type did not affect performance. These findings suggest that severing the cortical connections between hemispheres splits visual perception, but does not create two independent conscious perceivers within one brain.


Asunto(s)
Estado de Conciencia/fisiología , Lateralidad Funcional/fisiología , Procedimiento de Escisión Encefálica/efectos adversos , Campos Visuales/fisiología , Percepción Visual/fisiología , Encéfalo/fisiología , Humanos , Pruebas del Campo Visual
17.
PLoS One ; 11(6): e0157770, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27333186

RESUMEN

The ability to consolidate procedural memories declines with increasing age. Prior knowledge enhances learning and memory consolidation of novel but related information in various domains. Here, we present evidence that prior motor experience-in our case piano skills-increases procedural learning and has a protective effect against age-related decline for the consolidation of novel but related manual movements. In our main experiment, we tested 128 participants with a sequential finger-tapping motor task during two sessions 24 hours apart. We observed enhanced online learning speed and offline memory consolidation for piano players. Enhanced memory consolidation was driven by a strong effect in older participants, whereas younger participants did not benefit significantly from prior piano experience. In a follow up independent control experiment, this compensatory effect of piano experience was not visible after a brief offline period of 30 minutes, hence requiring an extended consolidation window potentially involving sleep. Through a further control experiment, we rejected the possibility that the decreased effect in younger participants was caused by training saturation. We discuss our results in the context of the neurobiological schema approach and suggest that prior experience has the potential to rescue memory consolidation from age-related cognitive decline.


Asunto(s)
Envejecimiento/fisiología , Trastornos de la Memoria/fisiopatología , Memoria/fisiología , Destreza Motora/fisiología , Adolescente , Adulto , Anciano , Femenino , Dedos , Humanos , Internet , Masculino , Consolidación de la Memoria/fisiología , Persona de Mediana Edad , Adulto Joven
18.
Haematologica ; 100(6): 794-800, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25795722

RESUMEN

Resimmune is a second-generation recombinant immunotoxin composed of the catalytic and translocation domains of diphtheria toxin fused to two single chain antibody fragments reactive with the extracellular domain of CD3ε. We gave intravenous infusions of Resimmune 2.5 - 11.25 µg/kg over 15 minutes to 30 patients (25 with cutaneous T-cell lymphoma, 3 with peripheral T-cell lymphoma, 1 with T-cell large granular lymphocytic leukemia and 1 with T-cell prolymphocytic leukemia) in an inter-patient dose escalation trial. The most common adverse events were fever, chills, hypotension, edema, hypoalbuminemia, hypophosphatemia, and transaminasemia. Among the 25 patients with cutaneous T-cell lymphoma, there were nine responses for a response rate of 36% (95% CI, 18%-57%) including four complete remissions (16%, 95% CI, 5%-36%). The durations of the complete remissions were 72+, 72+, 60+ and 38+ months. There were five partial remissions lasting 3, 3, 3+, 6+ and 14 months. Of 17 patients with a modified skin weighted assessment tool score <50, 17 patients with stage IB/IIB, and 11 patients with both a score <50 and stage IB/IIB, nine (53%), eight (47%), and eight (73%) had responses, respectively. Further studies of Resimmune in patients with low tumor burden, stage IB-IIB cutaneous T-cell lymphoma are warranted. This trial is registered at clinicaltrials.gov as #NCT00611208.


Asunto(s)
Complejo CD3/inmunología , Toxina Diftérica/administración & dosificación , Fragmentos de Inmunoglobulinas/administración & dosificación , Inmunotoxinas/administración & dosificación , Linfoma Cutáneo de Células T/tratamiento farmacológico , Linfoma Cutáneo de Células T/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Toxina Diftérica/efectos adversos , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Fragmentos de Inmunoglobulinas/efectos adversos , Inmunotoxinas/efectos adversos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/efectos adversos , Inducción de Remisión/métodos , Enfermedades Vasculares/inducido químicamente , Adulto Joven
19.
J Neurodev Disord ; 5(1): 9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23566357

RESUMEN

BACKGROUND: Minocycline is a tetracycline derivative that readily crosses the blood brain barrier and appears to have beneficial effects on neuroinflammation, microglial activation and neuroprotection in a variety of neurological disorders. Both microglial activation and neuroinflammation have been reported to be associated with autism. The study was designed to evaluate the effects of minocycline treatment on markers of neuroinflammation and autism symptomatology in children with autism and a history of developmental regression. METHODS: Eleven children were enrolled in an open-label trial of six months of minocycline (1.4 mg/kg). Ten children completed the trial. Behavioral measures were collected and cerebrospinal fluid (CSF), serum and plasma were obtained before and at the end of minocycline treatment and were analyzed for markers of neuroinflammation. RESULTS: Clinical improvements were negligible. The laboratory assays demonstrated significant changes in the expression profile of the truncated form of brain derived neurotrophic factor (BDNF) (P = 0.042) and hepatic growth factor (HGF) (P = 0.028) in CSF. In serum, the ratio of the truncated BDNF form and α-2 macroglobulin (α-2 M), was also significantly lower (P = 0.028) while the mature BDNF/α-2 M ratio revealed no difference following treatment. Only the chemokine CXCL8 (IL-8) was significantly different (P = 0.047) in serum while no significant changes were observed in CSF or serum in chemokines such as CCL2 (MCP-1) or cytokines such as TNF-α, CD40L, IL-6, IFN-γ and IL-1ß when pre- and post-treatment levels of these proteins were compared. No significant pre- and post-treatment changes were seen in the profiles of plasma metalloproteinases, putative targets of the effects of minocycline. CONCLUSIONS: Changes in the pre- and post-treatment profiles of BDNF in CSF and blood, HGF in CSF and CXCL8 (IL-8) in serum, suggest that minocycline may have effects in the CNS by modulating the production of neurotrophic growth factors. However, in this small group of children, no clinical improvements were observed during or after the six months of minocycline administration. TRIAL REGISTRATION: NCT00409747.

20.
J Immunol Methods ; 391(1-2): 103-11, 2013 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-23470981

RESUMEN

Targeted cell therapies are possible through the generation of recombinant fusion proteins that combine a toxin, such as diphtheria toxin (DT), with an antibody or other molecule that confers specificity. Upon binding of the fusion protein to the cell of interest, the diphtheria toxin is internalized which results in protein synthesis inhibition and subsequent cell death. We have recently expressed and purified the recombinant soluble porcine CTLA-4 both with and without N-glycosylation in yeast Pichia pastoris for in vivo use in our preclinical swine model. The glycosylated and non-N-glycosylated versions of this recombinant protein each bind to a porcine CD80 expressing B-cell lymphoma line (LCL13271) with equal affinity (K(D)=13 nM). In this study we have linked each of the glycosylated and non-N-glycosylated soluble porcine CTLA-4 proteins to the truncated diphtheria toxin DT390 through genetic engineering yielding three versions of the porcine CTLA-4 fusion toxins: 1) monovalent glycosylated soluble porcine CTLA-4 fusion toxin; 2) monovalent non-N-glycosylated soluble porcine CTLA-4 fusion toxin and 3) bivalent non-N-glycosylated soluble porcine CTLA-4 fusion toxin. Protein synthesis inhibition analysis demonstrated that while all three fusion toxins are capable of inhibiting protein synthesis in vitro, the non-N-glycosylated porcine CTLA-4 isoforms function most efficiently. Binding analysis using flow cytometry of the porcine CTLA-4 fusion toxins to LCL13271 cells also demonstrated that the non-N-glycosylated porcine CTLA-4 isoforms bind to these cells with higher affinity compared to the glycosylated fusion toxin. The monovalent non-N-glycosylated porcine CTLA-4 fusion toxin was tested in vivo. NSG (NOD/SCID IL-2 receptor γ(-)/(-)) mice were injected with porcine CD80(+) LCL13271 tumor cells. All animals succumbed to tumors and those treated with the monovalent non-N-glycosylated porcine CTLA-4 fusion toxin survived longer based on a symptomatic scoring system compared to the untreated controls. This recombinant protein may therefore provide a novel approach for in vivo depletion of porcine antigen presenting cells (APCs) for studies investigating the induction of transplantation tolerance, autoimmune disease and cancer treatment.


Asunto(s)
Antígeno CTLA-4/administración & dosificación , Toxina Diftérica/administración & dosificación , Inmunoterapia/métodos , Inmunotoxinas/administración & dosificación , Linfoma de Células B/terapia , Animales , Antígeno B7-1/inmunología , Antígeno B7-1/metabolismo , Antígeno CTLA-4/biosíntesis , Antígeno CTLA-4/genética , Antígeno CTLA-4/metabolismo , Línea Celular , Toxina Diftérica/biosíntesis , Toxina Diftérica/genética , Toxina Diftérica/metabolismo , Citometría de Flujo , Glicosilación , Inmunotoxinas/genética , Inmunotoxinas/metabolismo , Subunidad gamma Común de Receptores de Interleucina/deficiencia , Subunidad gamma Común de Receptores de Interleucina/genética , Linfoma de Células B/inmunología , Linfoma de Células B/metabolismo , Ratones , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Pichia/genética , Pichia/metabolismo , Unión Proteica , Biosíntesis de Proteínas , Procesamiento Proteico-Postraduccional , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Recombinantes de Fusión/farmacología , Porcinos
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