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1.
Neotrop. ichthyol ; 20(3): e210160, 2022. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1406129

RESUMO

For 175 years, an unremarkable bass, the Grape-eye Seabass (Hemilutjanus macrophthalmos), has been known from coastal waters in the Eastern Pacific. To date, its phylogenetic placement and classification have been ignored. A preliminary osteological examination of Hemilutjanus hinted that it may have affinities with the Acropomatiformes. To test this hypothesis, we conducted a phylogenetic analysis using UCE and Sanger sequence data to study the placement of Hemilutjanus and the limits and relationships of the Acropomatiformes. We show that Hemilutjanus is a malakichthyid, and our results corroborate earlier studies that have resolved a polyphyletic Polyprionidae; accordingly, we describe Stereolepididae, new family, for Stereolepis. With these revisions, the Acropomatiformes is now composed of the: Acropomatidae; Banjosidae; Bathyclupeidae; Champsodontidae; Creediidae; Dinolestidae; Epigonidae; Glaucosomatidae; Hemerocoetidae; Howellidae; Lateolabracidae; Malakichthyidae; Ostracoberycidae; Pempheridae; Pentacerotidae; Polyprionidae; Scombropidae; Stereolepididae, new family; Symphysanodontidae; Synagropidae; and Schuettea. Finally, using our new hypothesis, we demonstrate that acropomatiforms repeatedly evolved bioluminescence and transitioned between shallow waters and the deep sea.


Durante más de 175 años el Serranido ojo de uva (Hemilutjanus macrophthalmos), un pez parecido a la lubina común, se conoce de las zonas costeras del Pacífico Oriental. Al día de hoy la posición filogenética de esta especie se desconoce. Un estudio preliminar de Hemilutjanus basado en caracteres osteológicos sugirió que esta especie puede tener afinidades con el orden Acropomatiformes. Para investigar la posición filogenética de Hemilutjanus y los límites y relaciones dentro del orden Acropomatiformes realizamos análisis filogenéticos utilizando datos de secuencias Sanger y de UCEs. Demostramos que Hemilutjanus es un malakichthyid y nuestros resultados recobran Polyprionidae como una familia polifilética corroboran así estudios anteriores. En consecuencia, diagnosticamos y describimos una nueva familia de peces, Stereolepididae, que incluye ambas especies del genero Stereolepis. Con esta revisión, ahora el orden Acropomatiformes se compone de las familias: Acropomatidae; Banjosidae; Bathyclupeidae; Champsodontidae; Creediidae; Dinolestidae; Epigonidae; Glaucosomatidae; Hemerocoetidae; Howellidae; Lateolabracidae; Malakichthyidae; Ostracoberycidae; Pempheridae; Pentacerotidae; Polyprionidae; Scombropidae; Stereolepididae, nueva familia; Symphysanodontidae; Synagropidae; y Schuettea. Finalmente, utilizando nuestra hipótesis filogenética, demostramos que bioluminiscencia ha evolucionado varias veces dentro de los miembros de Acropomatiformes y tambien demostramos múltiples transiciones entre aguas someras y zonas profundas del océano dentro de este grupo.


Assuntos
Animais , Filogenia , Especificidade da Espécie , Bass/anatomia & histologia , Perciformes/anatomia & histologia , Oceano Pacífico
2.
Chembiochem ; 20(18): 2390-2401, 2019 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-31026110

RESUMO

Class 1 myosins (Myo1s) were the first unconventional myosins identified and humans have eight known Myo1 isoforms. The Myo1 family is involved in the regulation of gene expression, cytoskeletal rearrangements, delivery of proteins to the cell surface, cell migration and spreading. Thus, the important role of Myo1s in different biological processes is evident. In this study, we have investigated the effects of pentachloropseudilin (PClP), a reversible and allosteric potent inhibitor of Myo1s, on angiogenesis. We demonstrated that treatment of cells with PClP promoted a decrease in the number of vessels. The observed inhibition of angiogenesis is likely to be related to the inhibition of cell proliferation, migration and adhesion, as well as to alteration of the actin cytoskeleton pattern, as shown on a PClP-treated HUVEC cell line. Moreover, we also demonstrated that PClP treatment partially prevented the delivery of integrins to the plasma membrane. Finally, we showed that PClP caused DNA strand breaks, which are probably repaired during the cell cycle arrest in the G1 phase. Taken together, our results suggest that Myo1s participate directly in the angiogenesis process.


Assuntos
Citoesqueleto de Actina/efeitos dos fármacos , Inibidores da Angiogênese/farmacologia , Ciclo Celular/efeitos dos fármacos , Hidrocarbonetos Clorados/farmacologia , Integrinas/metabolismo , Pirróis/farmacologia , Inibidores da Angiogênese/toxicidade , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Hidrocarbonetos Clorados/toxicidade , Integrinas/genética , Miosina Tipo I/metabolismo , Pirróis/toxicidade , RNA Mensageiro/metabolismo
3.
Chembiochem, v. 20, n. 18, p. 2390-2401, set. 2020
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3196

RESUMO

Class 1 myosins (Myo1s) were the first unconventional myosins identified and humans have eight known Myo1 isoforms. The Myo1 family is involved in the regulation of gene expression, cytoskeletal rearrangements, delivery of proteins to the cell surface, cell migration and spreading. Thus, the important role of Myo1s in different biological processes is evident. In this study, we have investigated the effects of pentachloropseudilin (PClP), a reversible and allosteric potent inhibitor of Myo1s, on angiogenesis. We demonstrated that treatment of cells with PClP promoted a decrease in the number of vessels. The observed inhibition of angiogenesis is likely to be related to the inhibition of cell proliferation, migration and adhesion, as well as to alteration of the actin cytoskeleton pattern, as shown on a PClP‐treated HUVEC cell line. Moreover, we also demonstrated that PClP treatment partially prevented the delivery of integrins to the plasma membrane. Finally, we showed that PClP caused DNA strand breaks, which are probably repaired during the cell cycle arrest in the G1 phase. Taken together, our results suggest that Myo1s participate directly in the angiogenesis process.

4.
Front Psychol ; 8: 204, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28261137

RESUMO

Many advances have been made over the last decades in describing, on the one hand, the link between reward-based learning and decision-making, and on the other hand, the link between impulsivity and decision-making. However, the association between reward-based learning and impulsivity remains poorly understood. In this study, we evaluated the association between individual differences in loss-minimizing and gain-maximizing behavior in a learning-based probabilistic decision-making task and individual differences in cognitive impulsivity. We found that low cognitive impulsivity was associated both with a better performance minimizing losses and maximizing gains during the task. These associations remained significant after controlling for mathematical skills and gender as potential confounders. We discuss potential mechanisms through which cognitive impulsivity might interact with reward-based learning and decision-making.

5.
Soc Cogn Affect Neurosci ; 11(6): 863-76, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27030510

RESUMO

Human altruism is often expressed through charitable donation-supporting a cause that benefits others in society, at cost to oneself. The underlying mechanisms of this other-regarding behavior remain imperfectly understood. By recording event-related-potential (ERP) measures of brain activity from human participants during a social gambling task, we identified markers of differential responses to receipt of monetary outcomes for oneself vs for a charitable cause. We focused our ERP analyses on the frontocentral feedback-related negativity (FRN) and three subcomponents of the attention-related P300 (P3) brain wave: the frontocentral P2 and P3a and the parietal P3b. The FRN distinguished between gains and losses for both self and charity outcomes. Importantly, this effect of outcome valence was greater for self than charity for both groups and was independent of two altruism-related measures: participants' pre-declared intended donations and the actual donations resulting from their choices. In contrast, differences in P3 subcomponents for outcomes for self vs charity strongly predicted both of our laboratory measures of altruism-as well as self-reported engagement in real-life altruistic behaviors. These results indicate that individual differences in altruism are linked to individual differences in the relative deployment of attention (as indexed by the P3) toward outcomes affecting other people.


Assuntos
Altruísmo , Ondas Encefálicas/fisiologia , Potenciais Evocados/fisiologia , Recompensa , Adolescente , Adulto , Potenciais Evocados P300/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
6.
Cereb Cortex ; 26(1): 1-11, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25139941

RESUMO

Adaptive choice behavior depends critically on identifying and learning from outcome-predicting cues. We hypothesized that attention may be preferentially directed toward certain outcome-predicting cues. We studied this possibility by analyzing event-related potential (ERP) responses in humans during a probabilistic decision-making task. Participants viewed pairs of outcome-predicting visual cues and then chose to wager either a small (i.e., loss-minimizing) or large (i.e., gain-maximizing) amount of money. The cues were bilaterally presented, which allowed us to extract the relative neural responses to each cue by using a contralateral-versus-ipsilateral ERP contrast. We found an early lateralized ERP response, whose features matched the attention-shift-related N2pc component and whose amplitude scaled with the learned reward-predicting value of the cues as predicted by an attention-for-reward model. Consistently, we found a double dissociation involving the N2pc. Across participants, gain-maximization positively correlated with the N2pc amplitude to the most reliable gain-predicting cue, suggesting an attentional bias toward such cues. Conversely, loss-minimization was negatively correlated with the N2pc amplitude to the most reliable loss-predicting cue, suggesting an attentional avoidance toward such stimuli. These results indicate that learned stimulus-reward associations can influence rapid attention allocation, and that differences in this process are associated with individual differences in economic decision-making performance.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Tomada de Decisões/fisiologia , Potenciais Evocados/fisiologia , Recompensa , Percepção Visual/fisiologia , Adolescente , Adulto , Mapeamento Encefálico/métodos , Sinais (Psicologia) , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Percepção Espacial/fisiologia , Adulto Jovem
7.
Front Behav Neurosci ; 7: 218, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24427126

RESUMO

Pupil dilation under constant illumination is a physiological marker where modulation is related to several cognitive functions involved in daily decision making. There is evidence for a role of pupil dilation change during decision-making tasks associated with uncertainty, reward-prediction errors and surprise. However, while some work suggests that pupil dilation is mainly modulated by reward predictions, others point out that this marker is related to uncertainty signaling and surprise. Supporting the latter hypothesis, the neural substrate of this marker is related to noradrenaline (NA) activity which has been also related to uncertainty signaling. In this work we aimed to test whether pupil dilation is a marker for uncertainty and surprise in a learning task. We recorded pupil dilation responses in 10 participants performing the Iowa Gambling Task (IGT), a decision-making task that requires learning and constant monitoring of outcomes' feedback, which are important variables within the traditional study of human decision making. Results showed that pupil dilation changes were modulated by learned uncertainty and surprise regardless of feedback magnitudes. Interestingly, greater pupil dilation changes were found during positive feedback (PF) presentation when there was lower uncertainty about a future negative feedback (NF); and by surprise during NF presentation. These results support the hypothesis that pupil dilation is a marker of learned uncertainty, and may be used as a marker of NA activity facing unfamiliar situations in humans.

8.
Front Hum Neurosci ; 6: 304, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23162451

RESUMO

In order to control behavior in an adaptive manner the brain has to learn how some situations and actions predict positive or negative outcomes. During the last decade cognitive neuroscientists have shown that the brain is able to evaluate and learn from outcomes within a few hundred milliseconds of their occurrence. This research has been primarily focused on the feedback-related negativity (FRN) and the P3, two event-related potential (ERP) components that are elicited by outcomes. The FRN is a frontally distributed negative-polarity ERP component that typically reaches its maximal amplitude 250 ms after outcome presentation and tends to be larger for negative than for positive outcomes. The FRN has been associated with activity in the anterior cingulate cortex (ACC). The P3 (~300-600 ms) is a parietally distributed positive-polarity ERP component that tends to be larger for large magnitude than for small magnitude outcomes. The neural sources of the P3 are probably distributed over different regions of the cortex. This paper examines the theories that have been proposed to explain the functional role of these two ERP components during outcome processing. Special attention is paid to extant literature addressing how these ERP components are modulated by outcome valence (negative vs. positive), outcome magnitude (large vs. small), outcome probability (unlikely vs. likely), and behavioral adjustment. The literature offers few generalizable conclusions, but is beset with a number of inconsistencies across studies. This paper discusses the potential reasons for these inconsistencies and points out some challenges that probably will shape the field over the next decade.

9.
Rev. latinoam. psicol ; Rev. latinoam. psicol;43(3): 455-471, sep. 2011. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-650079

RESUMO

Investigaciones con Potenciales Relacionados a Eventos han demostrado la existencia de un componente llamado Negatividad Relacionada a Retroalimentación de Error, el cual ha sido referido como una deflexión negativa que distingue entre ganancias y pérdidas, en tanto resultados esperados y no esperados respectivamente. Así, mientras algunos estudios han operacionalizado la idea de resultado esperado como la probabilidad de ganar vs. Perder, otros lo han hecho como la magnitud esperada de las recompensas. Hasta ahora existe poca investigación tendiente a observar cómo estas interpretaciones alternativas de "resultado esperado", o su interacción en términos de un modelo de "valor esperado" que las integre, afectan la Negatividad Relacionada a Retroalimentación de Error. El presente trabajo contextualiza el estudio de los mecanismos cerebrales asociados a la toma de decisiones, situando los estudios de Negatividad Relacionada a Retroalimentación de Error en su contexto teórico, revisa las dos tendencias de estudio desarrolladas hasta la fecha y explora posibilidades de ampliación del estudio de este componente en el contexto del naciente campo transdisciplinario de la neuroeconomía.


Studies using Event-Related Potentials have shown the existence of a component called Feedback Error-Related Negativity (fERN). This component has been characterized as a negative deflection which responds differentially to profits and losses in terms of expected and unexpected outcomes. Thus, while some studies have defined the idea of "expected outcome" as the probability to win vs. to lose, others have defined it as the expected size of rewards. How these alternative interpretations of "expected outcome" affect the fERN's research, and the effects of their interaction under a specific model of "expected value" has not been properly assessed. This work contextualizes the general study of neural mechanisms involved in decisionmaking processes, putting the fERN studies in context; besides, it reviews the two main approaches to its research; and finally, it explores the possibilities to further expand the fERN studies, in the context of the transdisciplinary rising field of neuroeconomics.

10.
Medisan ; 14(3)mar.-abr. 2010. ilus
Artigo em Espanhol | LILACS | ID: lil-576599

RESUMO

Se presenta el caso clínico de un adolescente con bajo peso, remitido desde el Hospital Infantil Sur de Santiago de Cuba a la consulta especializada de cirugía ortognática en el Hospital Provincial Docente Saturnino Lora, con vista a tratar de que pudiera cerrar la boca y masticar alimentos, lo cual era imposible con la malformación. Las graves complicaciones respiratorias después de la operación impidieron la rehabilitación adecuada.


A case report of a teenager underweight referred from Santiago de Cuba Southern Children Hospital to the Specialized Department of Orthognathic Surgery in Saturnino Lora Provincial Teaching Hospital is presented in order to try he could close his mouth and chew foods, which was impossible with the malformation. Severe respiratory complications after surgery impeded the appropriate rehabilitation.


Assuntos
Humanos , Masculino , Adolescente , Ossos Faciais , Músculos Faciais , Síndrome de Horner , Recém-Nascido , Paralisia Facial/congênito , Relatos de Casos
11.
Neuroimage ; 51(3): 1194-204, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20302950

RESUMO

Feedback error-related negativity (fERN) has been referred to as a negative deflection in the event related potential (ERP), which distinguishes between wins and losses in terms of expected and unexpected outcomes. Some studies refer to the "expected outcome" as the probability to win vs. to lose, and others as expected size of rewards. We still do not know much about whether these alternative interpretations of "expected outcome" affect the fERN in a different manner, nor do we know the effect of their interaction in an expected value fashion. We set a gambling task with four game categories; two had the same expected value, while the other two categories were equivalent to the first ones, but alternatively in the size or probability of the offered rewards. Results show that fERN preceded by a P200, and followed by a Pe-like wave differentiates between losing in the category with a higher expected value and the rest of the experimental conditions. fERN differentiates between wins and losses, but changes in the size and probability of rewards impact the fERN amplitude only in win conditions. Results also show greater positivity following win feedback when the size and/or probability of the outcome rewards were higher, so that the higher the expected value the greater the positivity following win feedback. Our findings support the notion that both the probability and size of the offered rewards modulate the motivational value for the win feedback, this being also true for their interaction in an expected value fashion.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Retroalimentação Fisiológica/fisiologia , Jogo de Azar , Reforço Psicológico , Recompensa , Assunção de Riscos , Adulto , Mapeamento Encefálico , Interpretação Estatística de Dados , Feminino , Humanos , Masculino
12.
Biol Res ; 41(3): 271-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19399340

RESUMO

In the last few decades, several works on event related potentials (ERPs hereafter) during sleep have been reported. In spite of numerous studies, clear methodological rules for this kind of study are often missing, making it difficult to valorize the scope of these results. We propose here a description of methodological aspects to be considered when evaluating ERPs during sleep. The use of Rechtschaffen and Kales rules versus automatic methods is assessed, plus the additional use of certain quantitative measures. Additionally, two topics are discussed which must be controlled in ERPs sleep studies: the First Night Effect, and sleep disturbances. Better control of experimental paradigms is relevant for the growth of the neuroscience of sleep.


Assuntos
Potenciais Evocados/fisiologia , Polissonografia/métodos , Fases do Sono/fisiologia , Eletroencefalografia , Eletromiografia , Eletroculografia , Humanos , Processamento de Sinais Assistido por Computador
13.
Biol. Res ; 41(3): 271-275, 2008. ilus, graf
Artigo em Inglês | LILACS | ID: lil-511917

RESUMO

In the last few decades, several works on event related potentials (ERPs hereafter) during sleep have been reported. In spite of numerous studies, clear methodological rules for this kind of study are often missing, making it difficult to valorize the scope of these results. We propose here a description of methodological aspects to be considered when evaluating ERPs during sleep. The use of Rechtschaffen and Kales rules versus automatic methods is assessed, plus the additional use of certain quantitative measures. Additionally, two topics are discussed which must be controlled in ERPs sleep studies: the First Night Effect, and sleep disturbances. Better control of experimental paradigms is relevant for the growth of the neuroscience of sleep.


Assuntos
Humanos , Potenciais Evocados/fisiologia , Polissonografia/métodos , Fases do Sono/fisiologia , Eletroencefalografia , Eletromiografia , Eletroculografia , Processamento de Sinais Assistido por Computador
14.
Acta med. Hosp. Clin. Quir. Hermanos Ameijeiras ; 4(2): 247-60, jul.-dic. 1990. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-112003

RESUMO

Los nuevos betalactámicos representan una valiosa adquisición en el tratamiento de las infecciones graves y moderadas. Estos novedosos antibióticos tienen un amplio espectro antimicrobiano, excelentes propiedades farmacocinéticas y muy baja toxicidad. Los betalactámicos de reciente adquisición incluyen los carbapenem y los monobactámicos. Los monobactámicos están representados fundamentalmente por el aztreonam, y los carbapenem por la combinación de thienamicin más cilastatín. Constituyen una alternativa excelente en la antibioticoterapia futura. En este artículo se revisan estos nuevos antibióticos en su espectro de acción y fundamentalmente su uso clínico


Assuntos
Carbapenêmicos/uso terapêutico , Monobactamas/uso terapêutico
15.
Rev. cuba. estomatol ; 27(1): 94-106, ene.-mar. 1990. tab
Artigo em Espanhol | LILACS | ID: lil-88794

RESUMO

Se realiza un estudio de 115 pacientes afectados de quistes y fístulas del conducto tirogloso (78 quistes y 37 fístulas), diagnosticados en los hospitales "Saturnino Lora" y Pediátrico Sur de Santiago de Cuba, desde 1972 hasta 1982, ambos años inclusive. Se analizan las distribuciones por edad y sexo de estas afecciones, sus hallazgos anatomopatológicos, así como sus aspectos diagnosticos y terapéuticos. Finalmente, se comentan los resultados obtenidos y se comparan con los de la literatura revisada, de cuyo análisis se extraen las conclusiones finales


Assuntos
Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Fístula , Cisto Tireoglosso
16.
Rev. cuba. estomatol ; 24(1): 93-100, ene.-abr. 1987. tab
Artigo em Espanhol | LILACS | ID: lil-96972

RESUMO

Se realiza un estudio retrospectivo sobre quistes y fístulas embrionarios del cuello durante el período comprendido entre enero de 1972 hasta diciembre de 1981, ambos inclusive. Dicha investigación se basó en 85 pacientes con afecciones confirmadas hísticamente; los quistes fueron más frecuentes que las fístulas con 59 y 26 respectivamente; el que más se presentó fue el tirogloso, así como la fístula tiroglosa. El grupo de edades más afectado correspondió a la tercera década y se encontró prevalencia del sexo femenino. La localización predominante fue en la línea media. Todos los datos fueron procesados por el método normal y el trabajo se ilustra mediante fotos y cuadros


Assuntos
Adolescente , Adulto , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Cistos/epidemiologia , Fístula/epidemiologia , Cuba
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