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1.
Nature ; 627(8002): 174-181, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38355804

RESUMEN

Social interactions represent a ubiquitous aspect of our everyday life that we acquire by interpreting and responding to visual cues from conspecifics1. However, despite the general acceptance of this view, how visual information is used to guide the decision to cooperate is unknown. Here, we wirelessly recorded the spiking activity of populations of neurons in the visual and prefrontal cortex in conjunction with wireless recordings of oculomotor events while freely moving macaques engaged in social cooperation. As animals learned to cooperate, visual and executive areas refined the representation of social variables, such as the conspecific or reward, by distributing socially relevant information among neurons in each area. Decoding population activity showed that viewing social cues influences the decision to cooperate. Learning social events increased coordinated spiking between visual and prefrontal cortical neurons, which was associated with improved accuracy of neural populations to encode social cues and the decision to cooperate. These results indicate that the visual-frontal cortical network prioritizes relevant sensory information to facilitate learning social interactions while freely moving macaques interact in a naturalistic environment.


Asunto(s)
Macaca , Corteza Prefrontal , Aprendizaje Social , Corteza Visual , Animales , Potenciales de Acción , Conducta Cooperativa , Señales (Psicología) , Toma de Decisiones/fisiología , Función Ejecutiva/fisiología , Macaca/fisiología , Neuronas/fisiología , Estimulación Luminosa , Corteza Prefrontal/citología , Corteza Prefrontal/fisiología , Recompensa , Aprendizaje Social/fisiología , Corteza Visual/citología , Corteza Visual/fisiología , Tecnología Inalámbrica
3.
Learn Behav ; 51(3): 228-245, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-35882748

RESUMEN

Tests of visuospatial memory following short (<1 s) and medium (1 to 30 s) delays have revealed characteristically different patterns of behavior in humans. These data have been interpreted as evidence for different memory systems operating during short (iconic memory) and long delays (working memory). Leising et al. (2019, Behavioural Processes, 169, Article 103957 ) found evidence for both systems in pigeons and humans completing a location change-detection task using a visual mask that disrupted accuracy following a short (100 ms), but not a long (1,000 ms) delay. Another common finding is that adding to-be-remembered items should disrupt accuracy after a long, but not short, delay. Experiments 1a and 1b reported this memory system crossover effect in pigeons and people, respectively, tested on location change detection with delays of 0, 100, and 1,000 ms and displays of two to 16 items. Experiments 2a and 2b reported that the color of the items had little (pigeons) or no (humans) effect on change-detection accuracy. Pigeons tested in Experiment 3 with longer delays (2,000, 4,000, and 8,000 ms) and large set sizes demonstrated the crossover effect with most displays but did not demonstrate an abrupt drop in accuracy characteristic of iconic memory. In Experiment 4, accuracy with novel types of change (color, shape, and size) was better after a 0-ms delay and above-chance levels on color and shape trials. These data demonstrate the memory system crossover effect in both humans and pigeons and expand our knowledge of the properties of memory systems across species.


Asunto(s)
Columbidae , Memoria a Corto Plazo , Humanos , Animales , Recuerdo Mental , Probabilidad
4.
Mar Drugs ; 20(2)2022 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-35200640

RESUMEN

Schistosomiasis has been controlled for more than 40 years with a single drug, praziquantel, and only one molluscicide, niclosamide, raising concern of the possibility of the emergence of resistant strains. However, the molecular targets for both agents are thus far unknown. Consequently, the search for lead compounds from natural sources has been encouraged due to their diverse structure and function. Our search for natural compounds with potential use in schistosomiasis control led to the identification of an algal species, Laurencia dendroidea, whose extracts demonstrated significant activity toward both Schistosoma mansoni parasites and their intermediate host snails Biomphalaria glabrata. In the present study, three seaweed-derived halogenated sesquiterpenes, (-)-elatol, rogiolol, and obtusol are proposed as potential lead compounds for the development of anthelminthic drugs for the treatment of and pesticides for the environmental control of schistosomiasis. The three compounds were screened for their antischistosomal and molluscicidal activities. The screening revealed that rogiolol exhibits significant activity toward the survival of adult worms, and that all three compounds showed activity against S. mansoni cercariae and B. glabrata embryos. Biomonitored fractioning of L. dendroidea extracts indicated elatol as the most active compound toward cercariae larvae and snail embryos.


Asunto(s)
Antihelmínticos , Laurencia , Moluscocidas , Sesquiterpenos , Animales , Antihelmínticos/aislamiento & purificación , Antihelmínticos/farmacología , Larva , Laurencia/química , Moluscocidas/aislamiento & purificación , Moluscocidas/farmacología , Schistosoma mansoni/efectos de los fármacos , Esquistosomiasis/tratamiento farmacológico , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología , Compuestos de Espiro/aislamiento & purificación , Compuestos de Espiro/farmacología
5.
Prostaglandins Other Lipid Mediat ; 156: 106575, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34116165

RESUMEN

Human B-lymphocytes express 5-lipoxygenase (5-LOX) and 5-LOX activating protein (FLAP) and can convert arachidonic acid to leukotriene B4. Mantle cell lymphoma (MCL) cells contain similar amounts of 5-LOX as human neutrophils but the function and mechanism of activation of 5-LOX in MCL cells, and in normal B-lymphocytes, are unclear. Here we show that the intrinsic 5-LOX pathway in the MCL cell line JeKo-1 has an essential role in migration and adherence of the cells, which are important pathophysiological characteristics of B-cell lymphoma. Incubation of JeKo-1 with the FLAP inhibitor GSK2190915 or the 5-LOX inhibitor zileuton, at a concentration below 1 µM, prior to stimulation with the chemotactic agent CXCL12, led to a significant reduction of migration. CRISPR/Cas9 mediated deletion of ALOX5 gene in JeKo-1 cells also led to a significantly decreased migration of the cells. Furthermore, 5-LOX and FLAP inhibitors markedly decreased the adherence of JeKo-1 cells to stromal cells. In comparison, these drugs had a similar effect on adherence of JeKo-1 cells as the Bruton tyrosine kinase inhibitor ibrutinib, which has a proven anti-tumour effect. These results indicate that inhibition of 5-LOX may be a novel treatment for MCL and certain other B-cell lymphomas.


Asunto(s)
Linfoma de Células del Manto
6.
Learn Behav ; 49(1): 76-84, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33742425

RESUMEN

Same/different abstract-concept learning experiments were conducted with two primate species and three avian species by progressively increasing the size of the training stimulus set of distinctly different pictures from eight to 1,024 pictures. These same/different learning experiments were trained with two pictures presented simultaneously. Transfer tests of same and different learning employed interspersed trials of novel pictures to assess the level of correct performance on the very first time of subjects had seen those pictures. All of the species eventually performed these tests with high accuracy, contradicting the long-accepted notion that nonhuman animals are unable to learn the concept of same/different. Capuchin and rhesus monkeys learned the concept more readily than did pigeons. Clark's nutcrackers and black-billed magpies learned as readily as monkeys, and even showed a slight advantage with the smallest training stimulus sets. Those tests of same/different learning were followed by delay procedures, such that a delay was introduced after the subjects responded to the sample picture and before the test picture. In the sequential same/different task, accuracy was shown to diminish when the stimulus on a previous trial matched the test picture previously shown on a different trial. This effect is known as proactive interference. The pigeons' proactive interference was greater at 10-s delays than 1-s delays, revealing time-based interference. By contrast, time delays had little or no effect on rhesus monkeys' proactive interference, suggesting that rhesus monkeys have better explicit memory of where and when they saw the potential interfering picture, revealing better event-based memory.


Asunto(s)
Formación de Concepto , Aprendizaje , Animales , Columbidae , Condicionamiento Operante , Memoria
7.
Int J Mol Sci ; 22(12)2021 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-34200679

RESUMEN

Lymphocyte migration to and sequestration in specific microenvironments plays a crucial role in their differentiation and survival. Lymphocyte trafficking and homing are tightly regulated by signaling pathways and is mediated by cytokines, chemokines, cytokine/chemokine receptors and adhesion molecules. The production of cytokines and chemokines is largely controlled by transcription factors in the context of a specific epigenetic landscape. These regulatory factors are strongly interconnected, and they influence the gene expression pattern in lymphocytes, promoting processes such as cell survival. The epigenetic status of the genome plays a key role in regulating gene expression during many key biological processes, and it is becoming more evident that dysregulation of epigenetic mechanisms contributes to cancer initiation, progression and drug resistance. Here, we review the signaling pathways that regulate lymphoma cell migration and adhesion with a focus on Mantle cell lymphoma and highlight the fundamental role of epigenetic mechanisms in integrating signals at the level of gene expression throughout the genome.


Asunto(s)
Linfocitos B/patología , Adhesión Celular , Movimiento Celular , Epigénesis Genética , Linfoma de Células del Manto/patología , Microambiente Tumoral/inmunología , Animales , Humanos , Linfoma de Células del Manto/inmunología , Transducción de Señal
8.
Int J Mol Sci ; 22(12)2021 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-34198491

RESUMEN

Rare germline pathogenic TP53 missense variants often predispose to a wide spectrum of tumors characterized by Li-Fraumeni syndrome (LFS) but a subset of variants is also seen in families with exclusively hereditary breast cancer (HBC) outcomes. We have developed a logistic regression model with the aim of predicting LFS and HBC outcomes, based on the predicted effects of individual TP53 variants on aspects of protein conformation. A total of 48 missense variants either unique for LFS (n = 24) or exclusively reported in HBC (n = 24) were included. LFS-variants were over-represented in residues tending to be buried in the core of the tertiary structure of TP53 (p = 0.0014). The favored logistic regression model describes disease outcome in terms of explanatory variables related to the surface or buried status of residues as well as their propensity to contribute to protein compactness or protein-protein interactions. Reduced, internally validated models discriminated well between LFS and HBC (C-statistic = 0.78-0.84; equivalent to the area under the ROC (receiver operating characteristic) curve), had a low risk for over-fitting and were well calibrated in relation to the known outcome risk. In conclusion, this study presents a phenotypic prediction model of LFS and HBC risk for germline TP53 missense variants, in an attempt to provide a complementary tool for future decision making and clinical handling.


Asunto(s)
Neoplasias de la Mama/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Síndrome de Li-Fraumeni/genética , Mutación Missense/genética , Proteína p53 Supresora de Tumor/química , Proteína p53 Supresora de Tumor/genética , Secuencia de Aminoácidos , Femenino , Mutación de Línea Germinal/genética , Humanos , Modelos Logísticos , Análisis Multivariante , Fenotipo , Conformación Proteica
9.
J Neurosci Res ; 98(9): 1745-1763, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-31762086

RESUMEN

The aging cochlea is subjected to a number of pathological changes to play a role in the onset of age-related hearing loss (ARHL). Although ARHL has often been thought of as the result of the loss of hair cells, it is in fact a disorder with a complex etiology, arising from the changes to both the organ of Corti and its supporting structures. In this study, we examine two aging pathologies that have not been studied in detail despite their apparent prevalence; the fusion, elongation, and engulfment of cochlear inner hair cell stereocilia, and the changes that occur to the tectorial membrane (TM), a structure overlying the organ of Corti that modulates its physical properties in response to sound. Our work demonstrates that similar pathological changes occur in these two structures in the aging cochleae of both mice and humans, examines the ultrastructural changes that underlie stereocilial fusion, and identifies the lost TM components that lead to changes in membrane structure. We place these changes into the context of the wider pathology of the aging cochlea, and identify how they may be important in particular for understanding the more subtle hearing pathologies that precede auditory threshold loss in ARHL.


Asunto(s)
Envejecimiento/fisiología , Cóclea/patología , Pérdida Auditiva/etiología , Estereocilios/patología , Membrana Tectoria/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Cóclea/ultraestructura , Femenino , Células Ciliadas Auditivas , Audición , Humanos , Masculino , Ratones , Ratones Endogámicos CBA , Persona de Mediana Edad , Órgano Espiral , Estereocilios/ultraestructura , Membrana Tectoria/fisiología , Membrana Tectoria/ultraestructura
10.
BMC Musculoskelet Disord ; 21(1): 275, 2020 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-32345281

RESUMEN

BACKGROUND: Shockwave therapy (SWT) is a commonly used intervention for a number of musculoskeletal conditions with varying clinical outcomes. However, the capacity of SWT to influence pathophysiological processes and the morphology of affected tissues remains unclear. The objective of the current review is to evaluate changes in imaging outcomes of musculoskeletal conditions following SWT. METHODS: A comprehensive search of Medline, Embase, Cochrane Controlled Trials Register, CINAHL and SportDiscus was conducted from inception to October 2018. Prospective clinical trials evaluating the effectiveness of SWT based on changes in imaging outcomes were eligible for inclusion. Articles were evaluated independently for risk of bias using the Cochrane Risk of Bias list and the Methodological Index for Non-Randomized Studies. Random-effects meta-analysis and meta-regression with a priori determined covariates was conducted for each condition to determine potential predictors of SWT effects. RESULTS: Sixty-three studies were included, with data from 27 studies available for effect size pooling. Meta-analyses and meta-regression on imaging outcomes were performed for rotator cuff calcific tendinitis (n = 11), plantar fasciitis (n = 7) and osteonecrosis of the femoral head (n = 9). There was an overall reduction in the size of measured lesion following SWT (MD 8.44 mm (95%CI -4.30, 12.57), p < 0.001) for calcium deposit diameter, (MD 0.92 mm (95%CI -0.03, 1.81), p = 0.04) for plantar fascia thickness and (MD 4.84% (95%CI -0.06, 9.75), p = 0.05) for lesion size in femoral head osteonecrosis. Meta-regression showed no influence of SWT dosage parameters, however, baseline lesion size was an independent predictor for changes in imaging outcomes. CONCLUSIONS: SWT altered the morphology of musculoskeletal conditions, potentially reflecting changes in underlying pathophysiological processes. The parameters of SWT dosage are not significant predictors of changes in imaging outcomes. Lack of adequate reporting of imaging outcomes limited the conclusions that could be drawn from the current review. Registration number: PROSPERO CRD42018091140.


Asunto(s)
Calcinosis/terapia , Diagnóstico por Imagen/estadística & datos numéricos , Tratamiento con Ondas de Choque Extracorpóreas/métodos , Enfermedades Musculoesqueléticas/terapia , Adulto , Anciano , Anciano de 80 o más Años , Calcinosis/diagnóstico por imagen , Ensayos Clínicos como Asunto , Diagnóstico por Imagen/métodos , Fascitis Plantar/terapia , Femenino , Necrosis de la Cabeza Femoral/terapia , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Musculoesqueléticas/diagnóstico por imagen , Enfermedades Musculoesqueléticas/fisiopatología , Evaluación de Resultado en la Atención de Salud , Estudios Prospectivos , Lesiones del Manguito de los Rotadores/patología
11.
Haematologica ; 103(4): 666-678, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29449436

RESUMEN

A subset of hematologic cancer patients is refractory to treatment or suffers relapse, due in part to minimal residual disease, whereby some cancer cells survive treatment. Cell-adhesion-mediated drug resistance is an important mechanism, whereby cancer cells receive survival signals via interaction with e.g. stromal cells. No genome-wide studies of in vitro systems have yet been performed to compare gene expression in different cell subsets within a co-culture and cells grown separately. Using RNA sequencing and species-specific read mapping, we compared transcript levels in human Jeko-1 mantle cell lymphoma cells stably adhered to mouse MS-5 stromal cells or in suspension within a co-culture or cultured separately as well as in stromal cells in co-culture or in separate culture. From 1050 differentially expressed transcripts in adherent mantle cell lymphoma cells, we identified 24 functional categories that together represent four main functional themes, anti-apoptosis, B-cell signaling, cell adhesion/migration and early mitosis. A comparison with previous mantle cell lymphoma and chronic lymphocytic leukemia studies, of gene expression differences between lymph node and blood, identified 116 genes that are differentially expressed in all three studies. From these genes, we suggest a core set of genes (CCL3, CCL4, DUSP4, ETV5, ICAM1, IL15RA, IL21R, IL4I1, MFSD2A, NFKB1, NFKBIE, SEMA7A, TMEM2) characteristic of cells undergoing cell-adhesion-mediated microenvironment signaling in mantle cell lymphoma/chronic lymphocytic leukemia. The model system developed and characterized here together with the core gene set will be useful for future studies of pathways that mediate increased cancer cell survival and drug resistance mechanisms.


Asunto(s)
Adhesión Celular/fisiología , Perfilación de la Expresión Génica , Linfoma/patología , Análisis de Secuencia de ARN , Células del Estroma/citología , Animales , Línea Celular , Línea Celular Tumoral , Supervivencia Celular , Técnicas de Cocultivo , Resistencia a Medicamentos , Regulación Neoplásica de la Expresión Génica , Humanos , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/patología , Linfoma de Células del Manto/genética , Linfoma de Células del Manto/patología , Ratones , Comunicación Paracrina
12.
Biochim Biophys Acta Gen Subj ; 1862(6): 1452-1461, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29550429

RESUMEN

BACKGROUND: Adaptive mutations that alter protein functionality are enriched within intrinsically disordered protein regions (IDRs), thus conformational flexibility correlates with evolvability. Pre-structured motifs (PreSMos) with transient propensity for secondary structure conformation are believed to be important for IDR function. The glucocorticoid receptor tau1core transcriptional activation domain (GR tau1core) domain contains three α-helical PreSMos in physiological buffer conditions. METHODS: Sixty change-of-function mutants affecting the intrinsically disordered 58-residue GR tau1core were studied using disorder prediction and molecular dynamics simulations. RESULTS: Change-of-function mutations were partitioned into seven clusters based on their effect on IDR predictions and gene activation activity. Some mutations selected from clusters characterized by mutations altering the IDR prediction score, altered the apparent stability of the α-helical form of one of the PreSMos in molecular dynamics simulations, suggesting PreSMo stabilization or destabilization as strategies for functional adaptation. Indeed all tested gain-of-function mutations affecting this PreSMo were associated with increased stability of the α-helical PreSMo conformation, suggesting that PreSMo stabilization may be the main mechanism by which adaptive mutations can increase the activity of this IDR type. Some mutations did not appear to affect PreSMo stability. CONCLUSIONS: Changes in PreSMo stability account for the effects of a subset of change-of-function mutants affecting the GR tau1core IDR. GENERAL SIGNIFICANCE: Long IDRs occur in about 50% of human proteins. They are poorly characterized despite much recent attention. Our results suggest the importance of a subtle balance between PreSMo stability and IDR activity, which may provide a novel target for future pharmaceutical intervention.


Asunto(s)
Proteínas Intrínsecamente Desordenadas/química , Simulación de Dinámica Molecular , Mutación , Conformación Proteica en Hélice alfa , Receptores de Glucocorticoides/química , Humanos , Proteínas Intrínsecamente Desordenadas/genética , Receptores de Glucocorticoides/genética , Activación Transcripcional
13.
Learn Behav ; 46(2): 107-123, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29492785

RESUMEN

This article describes an approach for training a variety of species to learn the abstract concept of same/different, which in turn forms the basis for testing proactive interference and list memory. The stimulus set for concept-learning training was progressively doubled from 8, 16, 32, 64, 128 . . . to 1,024 different pictures with novel-stimulus transfer following learning. All species fully learned the same/different abstract concept: capuchin and rhesus monkeys learned more readily than pigeons; nutcrackers and magpies were at least equivalent to monkeys and transferred somewhat better following initial training sets. A similar task using the 1,024-picture set plus delays was used to test proactive interference on occasional trials. Pigeons revealed greater interference with 10-s than with 1-s delays, whereas delay time had no effect on rhesus monkeys, suggesting that the monkeys' interference was event based. This same single-item same/different task was expanded to a 4-item list memory task to test animal list memory. Humans were tested similarly with lists of kaleidoscope pictures. Delays between the list and test were manipulated, resulting in strong initial recency effects (i.e., strong 4th-item memory) at short delays and changing to a strong primacy effect (i.e., strong 1st-item memory) at long delays (pigeons 0-s to 10-s delays; monkeys 0-s to 30-s delays; humans 0-s to 100-s delays). Results and findings are discussed in terms of these species' cognition and memory comparisons, evolutionary implications, and future directions for testing other species in these synergistically related tasks.


Asunto(s)
Cognición/fisiología , Formación de Concepto/fisiología , Aprendizaje/fisiología , Animales , Aves , Aprendizaje Discriminativo/fisiología , Haplorrinos , Memoria/fisiología , Especificidad de la Especie
14.
Int J Mol Sci ; 19(10)2018 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-30308971

RESUMEN

Conformational protein properties are coupled to protein functionality and could provide a useful parameter for functional annotation of differentially expressed genes in transcriptome studies. The aim was to determine whether predicted intrinsic protein disorder was differentially associated with proteins encoded by genes that are differentially regulated in lymphoma cells upon interaction with stromal cells, an interaction that occurs in microenvironments, such as lymph nodes that are protective for lymphoma cells during chemotherapy. Intrinsic disorder protein properties were extracted from the Database of Disordered Protein Prediction (D²P²), which contains data from nine intrinsic disorder predictors. Proteins encoded by differentially regulated cell-adhesion regulated genes were enriched in intrinsically disordered regions (IDRs) compared to other genes both with regard to IDR number and length. The enrichment was further ascribed to down-regulated genes. Consistently, a higher proportion of proteins encoded by down-regulated genes contained at least one IDR or were completely disordered. We conclude that down-regulated genes in stromal cell-adherent lymphoma cells encode proteins that are characterized by elevated levels of intrinsically disordered conformation, indicating the importance of down-regulating functional mechanisms associated with intrinsically disordered proteins in these cells. Further, the approach provides a generally applicable and complementary alternative to classification of differentially regulated genes using gene ontology or pathway enrichment analysis.


Asunto(s)
Adhesión Celular/genética , Regulación Neoplásica de la Expresión Génica , Proteínas Intrínsecamente Desordenadas/genética , Linfoma/genética , Transcriptoma , Perfilación de la Expresión Génica , Humanos
15.
Psychol Sci ; 28(4): 437-444, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28151701

RESUMEN

Corvids (birds of the family Corvidae) display intelligent behavior previously ascribed only to primates, but such feats are not directly comparable across species. To make direct species comparisons, we used a same/different task in the laboratory to assess abstract-concept learning in black-billed magpies ( Pica hudsonia). Concept learning was tested with novel pictures after training. Concept learning improved with training-set size, and test accuracy eventually matched training accuracy-full concept learning-with a 128-picture set; this magpie performance was equivalent to that of Clark's nutcrackers (a species of corvid) and monkeys (rhesus, capuchin) and better than that of pigeons. Even with an initial 8-item picture set, both corvid species showed partial concept learning, outperforming both monkeys and pigeons. Similar corvid performance refutes the hypothesis that nutcrackers' prolific cache-location memory accounts for their superior concept learning, because magpies rely less on caching. That corvids with "primitive" neural architectures evolved to equal primates in full concept learning and even to outperform them on the initial 8-item picture test is a testament to the shared (convergent) survival importance of abstract-concept learning.


Asunto(s)
Conducta Animal/fisiología , Formación de Concepto/fisiología , Passeriformes/fisiología , Animales , Femenino , Masculino , Especificidad de la Especie
16.
J Vis ; 17(11): 4, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28877535

RESUMEN

Since sensory measurements are noisy, an observer is rarely certain about the identity of a stimulus. In visual perception tasks, observers generally take their uncertainty about a stimulus into account when doing so helps task performance. Whether the same holds in visual working memory tasks is largely unknown. Ten human and two monkey subjects localized a single change in orientation between a sample display containing three ellipses and a test display containing two ellipses. To manipulate uncertainty, we varied the reliability of orientation information by making each ellipse more or less elongated (two levels); reliability was independent across the stimuli. In both species, a variable-precision encoding model equipped with an "uncertainty-indifferent" decision rule, which uses only the noisy memories, fitted the data poorly. In both species, a much better fit was provided by a model in which the observer also takes the levels of reliability-driven uncertainty associated with the memories into account. In particular, a measured change in a low-reliability stimulus was given lower weight than the same change in a high-reliability stimulus. We did not find strong evidence that observers took reliability-independent variations in uncertainty into account. Our results illustrate the importance of studying the decision stage in comparison tasks and provide further evidence for evolutionary continuity of working memory systems between monkeys and humans.


Asunto(s)
Memoria a Corto Plazo/fisiología , Orientación/fisiología , Percepción Visual/fisiología , Adulto , Animales , Femenino , Haplorrinos , Humanos , Masculino , Reproducibilidad de los Resultados , Análisis y Desempeño de Tareas , Incertidumbre , Adulto Joven
17.
Environ Microbiol ; 18(8): 2319-25, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-25808912

RESUMEN

Antioxidant activity of symbiotic organisms known as lichens is an intriguing field of research because of its strong contribution to their ability to withstand extremes of physical and biological stress (e.g. desiccation, temperature, UV radiation and microbial infection). We present a comparative study on the antioxidant activities of 76 Icelandic and 41 Hawaiian lichen samples assessed employing the DPPH- and FRAP-based antioxidant assays. Utilizing this unprecedented sample size, we show that while highest individual sample activity is present in the Icelandic dataset, the overall antioxidant activity is higher for lichens found in Hawaii. Furthermore, we report that lichens from the genus Peltigera that have been described as strong antioxidant producers in studies on Chinese, Russian and Turkish lichens also show high antioxidant activities in both Icelandic and Hawaiian lichen samples. Finally, we show that opportunistic sampling of lichens in both Iceland and Hawaii will yield high numbers of lichen species that exclusively include green algae as photobiont.


Asunto(s)
Antioxidantes/análisis , Líquenes/química , Hawaii , Líquenes/clasificación , Líquenes/crecimiento & desarrollo , Líquenes/efectos de la radiación , Rayos Ultravioleta
18.
J Urban Health ; 93 Suppl 1: 68-77, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26696002

RESUMEN

This paper explores theoretical, spatial, and mediatized pathways through which policing poses harms to the health of marginalized communities in the urban USA, including analysis of two recent and widely publicized incidents of officer-involved killings in Ferguson, Missouri and Staten Island, New York. We examine the influence of the "broken windows" model in both policing and public health, revealing alternate institutional strategies for responding to urban disorder in the interests of the health and safety of the city. Drawing on ecosocial theory and medical anthropology, we consider the roles of the segregated built environment and historical experience in the embodiment of structural vulnerability with respect to police violence. We examine the recent shootings of Eric Garner and Michael Brown as the most visible, most circulated symbols of this complex and contradictory terrain, focusing on the pathways through which theories of causality authorize violent and/or caring intervention by the state. We show how police killings reveal an underlying and racialized association between disorder and deviance that becomes institutionalized and embodied through spatial and symbolic pathways. If public health workers and advocates are to play a role in responding to the call of the Black Lives Matter movement, it is important to understand the interpretations and translations of urban social life that circulate on the streets, in the media, in public policy, and in institutional practice.


Asunto(s)
Aplicación de la Ley/métodos , Policia , Seguridad , Salud Urbana , Violencia/prevención & control , Negro o Afroamericano , Ambiente , Humanos , Missouri , Ciudad de Nueva York , Áreas de Pobreza , Salud Pública , Política Pública , Características de la Residencia/estadística & datos numéricos
19.
Planta Med ; 82(9-10): 800-15, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27159673

RESUMEN

The following review covers the primary literature concerning marine natural products isolated for the first time from organisms collected around the islands of Hawaii published in the 51-year period 1964 to July 2015. The review is divided into seven main sections based on major taxonomic groupings; algae, sponges, mollusks, miscellaneous invertebrates, cyanobacteria, bacteria, and fungi. The aim of the review is to discuss the compounds and information concerning their original biological activity and other potentially interesting properties. The majority of the 320 structures of isolated compounds are not shown directly in the review but are contained in the Supporting Information section in 22 figures, Figs. 1 S-22 S. The Supporting Information section also contains Table 1 S that has information relating to the taxonomic identification of the source organism of each compound, collection location of the source organism, a trivial or semi-systematic name for each compound, as well as its general structural class. The authors hope that this review will be the spawning ground for other reviews and the basis for a great deal more research into the marine life found in Hawaiian waters.


Asunto(s)
Productos Biológicos/historia , Animales , Organismos Acuáticos , Hawaii , Historia del Siglo XX , Historia del Siglo XXI , Humanos
20.
Learn Behav ; 44(4): 320-328, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27059232

RESUMEN

Previous work in discrimination learning has shown that nonmatching (oddity) tasks are learned faster and more accurately than comparable matching tasks. This learning advantage has been coined the oddity preference effect (Wright & Delius in Journal of Experimental Psychology: Animal Behavior Processes, 31, 425-432. doi: 10.1037/0097-7403.31.4.425 , 2005). Pigeons trained in a nonmatching task, following training in a same/different (S/D) task, learned the abstract concept of difference (Daniel et al., in Animal Cognition, 18(4), 831-837, 2015), but they did not show the expected faster acquisition or high levels of transfer from the oddity preference effect. In the present study, experimentally naïve pigeons were trained in an identical nonmatching task to examine whether they would show the oddity preference effect on abstract-concept learning. These experimentally naïve pigeons did show an oddity preference effect; their transfer to novel configurations was above chance with the initial (smallest) set size (3-item set) and was substantially more accurate than novel transfer in similar match-to-sample (MTS) or S/D tasks (Bodily et al., in Journal of Experimental Psychology: Animal Behavior Processes, 34, 178-184. doi: 10.1037/0097-7403.34.1.178 , 2008; Katz & Wright in Journal of Experimental Psychology: Animal Behavior Processes, 32, 80-86. doi: 10.1037/0097-7403.32.1.80 , 2006). As the number exemplars in the training set increased, transfer to novel configurations increased and reached equivalence to trained-stimulus performance with a 24-item set. Despite this transfer being equal to baseline performance with a 24-item set, subsequent transfers following training with larger set sizes declined before eventually rising again to baseline performance. This unusual set-size function (with inflection points at the 24- and 96-set sizes) suggests that these pigeons may have combined item-specific and relational learning strategies with differing emphasis as they acquired the abstract concept.


Asunto(s)
Formación de Concepto , Aprendizaje Discriminativo , Transferencia de Experiencia en Psicología , Animales , Columbidae , Aprendizaje
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