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1.
Gels ; 10(8)2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39195070

RESUMEN

The pH- and thermo-responsive behavior of polymeric hydrogels MC-co-MA have been studied in detail using dynamic light scattering DLS, scanning electron microscopy SEM, nuclear magnetic resonance (1H NMR) and rheology to evaluate the conformational changes, swelling-shrinkage, stability, the ability to flow and the diffusion process of nanoparticles at several temperatures. Furthermore, polymeric systems functionalized with acrylic acid MC and acrylamide MA were subjected to a titration process with a calcium chloride CaCl2 solution to analyze its effect on the average particle diameter Dz, polymer structure and the intra- and intermolecular interactions in order to provide a responsive polymer network that can be used as a possible nanocarrier for drug delivery with several benefits. The results confirmed that the structural changes in the sensitive hydrogels are highly dependent on the corresponding critical solution temperature CST of the carboxylic (-COOH) and amide (-CONH2) functional groups and the influence of calcium ions Ca2+ on the formation or breaking of hydrogen bonds, as well as the decrease in electrostatic repulsions generated between the polymer chains contributing to a particle agglomeration phenomenon. The temperature leads to a re-arrangement of the polymer chains, affecting the viscoelastic properties of the hydrogels. In addition, the diffusion coefficients D of nanoparticles were evaluated, showing a closeness among with the morphology, shape, size and temperature, resulting in slower diffusions for larger particles size and, conversely, the diffusion in the medium increasing as the polymer size is reduced. Therefore, the hydrogels exhibited a remarkable response to pH and temperature variations in the environment. During this research, the functionality and behavior of the polymeric nanoparticles were observed under different analysis conditions, which revealed notable structural changes and further demonstrated the nanoparticles promising high potential for drug delivery applications. Hence, these results have sparked significant interest in various scientific, industrial and technological fields.

2.
Pharmaceutics ; 16(8)2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39204362

RESUMEN

Over the last decade, scientists have shifted their focus to the development of smart carriers for the delivery of chemotherapeutics in order to overcome the problems associated with traditional chemotherapy, such as poor aqueous solubility and bioavailability, low selectivity and targeting specificity, off-target drug side effects, and damage to surrounding healthy tissues. Nanofiber-based drug delivery systems have recently emerged as a promising drug delivery system in cancer therapy owing to their unique structural and functional properties, including tunable interconnected porosity, a high surface-to-volume ratio associated with high entrapment efficiency and drug loading capacity, and high mass transport properties, which allow for controlled and targeted drug delivery. In addition, they are biocompatible, biodegradable, and capable of surface functionalization, allowing for target-specific delivery and drug release. One of the most common fiber production methods is electrospinning, even though the relatively two-dimensional (2D) tightly packed fiber structures and low production rates have limited its performance. Forcespinning is an alternative spinning technology that generates high-throughput, continuous polymeric nanofibers with 3D structures. Unlike electrospinning, forcespinning generates fibers by centrifugal forces rather than electrostatic forces, resulting in significantly higher fiber production. The functionalization of nanocarriers on nanofibers can result in smart nanofibers with anticancer capabilities that can be activated by external stimuli, such as light. This review addresses current trends and potential applications of light-responsive and dual-stimuli-responsive electro- and forcespun smart nanofibers in cancer therapy, with a particular emphasis on functionalizing nanofiber surfaces and developing nano-in-nanofiber emerging delivery systems for dual-controlled drug release and high-precision tumor targeting. In addition, the progress and prospective diagnostic and therapeutic applications of light-responsive and dual-stimuli-responsive smart nanofibers are discussed in the context of combination cancer therapy.

3.
Environ Sci Technol ; 2024 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-39034620

RESUMEN

Sublethal exposure to imidacloprid and other neonicotinoid insecticides may affect the neurological functions of birds. As such, behavior may be compromised. Here, we tested experimentally the effects of 1 and 6 mg/kg bw of imidacloprid on the antipredator behavioral responses of the red-legged partridge (Alectoris rufa) to simulated predator threats. Sixty-six partridges were challenged in groups or individually to intra- and interspecific alarm calls, to a raptor silhouette (aerial predation risk), and to a fox model (terrestrial predation risk). Antipredator behaviors were recorded as active (escape, active vigilance) and passive (passive vigilance, crouching, and freezing) responses. Latency in response to the stimuli, percentage of individuals who responded, response duration, speed of active responses, and vocalizations were measured. In experiments with partridges in the group, crouching against simulated predation risk lasted less time in birds treated with 6 mg a.i./kg bw than in control birds. In the experiments with individual partridges, passive vigilance against the intraspecific alarm lasted longer in birds treated with 6 mg a.i./kg bw than in control birds. The observed hyperreactivity to the predatory threat after a sublethal imidacloprid exposure can have consequences on survival under field conditions, where predation is a main driver of population dynamics.

4.
Adipocyte ; 13(1): 2374062, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38953241

RESUMEN

Obesity is associated with a low-grade chronic inflammatory process characterized by higher circulating TNFα levels, thus contributing to insulin resistance. This study evaluated the effect of silybin, the main bioactive component of silymarin, which has anti-inflammatory properties, on TNFα levels and its impact on glucose uptake in the adipocyte cell line 3T3-L1 challenged with two different inflammatory stimuli, TNFα or lipopolysaccharide (LPS). Silybin's pre-treatment effect was evaluated in adipocytes pre-incubated with silybin (30 or 80 µM) before challenging with the inflammatory stimuli (TNFα or LPS). For the post-treatment effect, the adipocytes were first challenged with the inflammatory stimuli and then post-treated with silybin. After treatments, TNFα production, glucose uptake, and GLUT4 protein expression were determined. Both inflammatory stimuli increased TNFα secretion, diminished GLUT4 expression, and significantly decreased glucose uptake. Silybin 30 µM only reduced TNFα secretion after the LPS challenge. Silybin 80 µM as post-treatment or pre-treatment decreased TNFα levels, improving glucose uptake. However, glucose uptake enhancement induced by silybin did not depend on GLUT4 protein expression. These results show that silybin importantly reduced TNFα levels and upregulates glucose uptake, independently of GLUT4 protein expression.


Asunto(s)
Células 3T3-L1 , Adipocitos , Glucosa , Lipopolisacáridos , Silibina , Factor de Necrosis Tumoral alfa , Animales , Silibina/farmacología , Ratones , Factor de Necrosis Tumoral alfa/metabolismo , Glucosa/metabolismo , Adipocitos/metabolismo , Adipocitos/efectos de los fármacos , Lipopolisacáridos/farmacología , Transportador de Glucosa de Tipo 4/metabolismo , Silimarina/farmacología
5.
Naturwissenschaften ; 111(4): 32, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856769

RESUMEN

Insects, despite possessing relatively small brains, exhibit noteworthy adaptive behaviors, making them intriguing subjects for understanding learning mechanisms. This study explores the learning capabilities of dragonfly larvae (Anisoptera: Aeshnidae) in conditioning experiments, shedding light on the cognitive processes that underpin their remarkable abilities. As apex predators, dragonflies play a crucial role in ecosystems, necessitating a diverse range of learning behaviors for survival and reproductive success. We addressed whether dragonfly larvae can differentiate between different colored stimuli and associate color with prey. Our experimental design demonstrated that dragonfly larvae are able to recognize conditioning stimuli. The findings contribute valuable insights into the cognitive abilities of dragonflies, suggesting that these insects can learn and discriminate colors of stimuli. Overall, this research broadens our understanding of insect learning and cognition, contributing to the broader field of animal behavior and memory.


Asunto(s)
Larva , Aprendizaje , Odonata , Animales , Odonata/fisiología , Larva/fisiología , Aprendizaje/fisiología , Color , Conducta Animal/fisiología
6.
Biomed Phys Eng Express ; 10(4)2024 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-38834037

RESUMEN

Understanding the brain response to thermal stimuli is crucial in the sensory experience. This study focuses on non-painful thermal stimuli, which are sensations induced by temperature changes without causing discomfort. These stimuli are transmitted to the central nervous system through specific nerve fibers and are processed in various regions of the brain, including the insular cortex, the prefrontal cortex, and anterior cingulate cortex. Despite the prevalence of studies on painful stimuli, non-painful thermal stimuli have been less explored. This research aims to bridge this gap by investigating brain functional connectivity during the perception of non-painful warm and cold stimuli using electroencephalography (EEG) and the partial directed coherence technique (PDC). Our results demonstrate a clear contrast in the direction of information flow between warm and cold stimuli, particularly in the theta and alpha frequency bands, mainly in frontal and temporal regions. The use of PDC highlights the complexity of brain connectivity during these stimuli and reinforces the existence of different pathways in the brain to process different types of non-painful warm and cold stimuli.


Asunto(s)
Encéfalo , Electroencefalografía , Humanos , Electroencefalografía/métodos , Masculino , Encéfalo/fisiología , Encéfalo/diagnóstico por imagen , Adulto , Femenino , Adulto Joven , Frío , Mapeo Encefálico/métodos , Calor , Dolor , Sensación Térmica/fisiología
7.
Perspect Behav Sci ; 47(1): 55-70, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38660498

RESUMEN

Stimuli produced by verbal responses (verbal stimuli) usually reveal something about the speakers who emitted them and about the environment where the verbal responses occurred (i.e., verbal stimuli can evoke in the listeners responses concerning the speakers and their environments). Verbal stimuli can also constitute supplementary stimulation that evokes responses which are already strong in the repertoire of some listeners or readers. Stimuli not produced by verbal responses (nonverbal stimuli), topographically similar to verbal stimuli, cannot reveal anything about speakers and their environments, but some of them can evoke responses that are already strong in the repertoire of some listeners or readers. Therefore, nonverbal stimuli allow one to distinguish clearly between the two functions of verbal stimuli. This article adopts a Skinnerian perspective and explores the implications of the supplementary function of stimuli for what is usually called understanding (and misunderstanding). Even when verbal stimuli are misunderstood, they can evoke verbal or nonverbal responses that are useful to the listeners. This effect can play a major role when it comes to aesthetic responses made to literary works, for example. Implications of the supplementary function of verbal stimuli for translations of ancient texts are also discussed. As supplementary stimulation, verbal stimuli can produce notable effects on the behavior of listeners and readers (even when the stimuli are misunderstood), although traditional mentalistic approaches to verbal behavior tend to neglect them.

8.
Cogn Emot ; 38(6): 954-962, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38554265

RESUMEN

Features of threatening cues and the associated context influence the perceived imminence of threat and the defensive responses evoked. To provide additional knowledge about how the directionality of a threat (i.e. directed-towards or away from the viewer) might impact defensive responses in humans, participants were shown pictures of a man carrying a gun (threat) or nonlethal object (neutral) directed-away from or towards the participant. Cardiac and electrodermal responses were collected. Compared to neutral images, threatening images depicting a gun directed-towards the participant induced sustained bradycardia and an increased electrodermal response, interpreted as immobility under attack. This defensive immobility reaction is evoked by high perceived threat and inescapable situations and indicates intense action preparation. Pictures of guns directed-away from the participant induced shorter bradycardia and no significant modulation of the electrodermal response compared to neutral pictures, which might be consistent with the perception of a less threatening situation. The results show that the directionality of threat stimuli is a key factor that prompts different patterns of defensive responses.


Asunto(s)
Miedo , Respuesta Galvánica de la Piel , Frecuencia Cardíaca , Humanos , Respuesta Galvánica de la Piel/fisiología , Masculino , Femenino , Frecuencia Cardíaca/fisiología , Adulto , Adulto Joven , Miedo/fisiología , Miedo/psicología , Estimulación Luminosa , Señales (Psicología)
9.
Molecules ; 29(3)2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38338380

RESUMEN

In recent years, nanocarriers have played an ever-increasing role in clinical and biomedical applications owing to their unique physicochemical properties and surface functionalities. Lately, much effort has been directed towards the development of smart, stimuli-responsive nanocarriers that are capable of releasing their cargos in response to specific stimuli. These intelligent-responsive nanocarriers can be further surface-functionalized so as to achieve active tumor targeting in a sequential manner, which can be simply modulated by the stimuli. By applying this methodological approach, these intelligent-responsive nanocarriers can be directed to different target-specific organs, tissues, or cells and exhibit on-demand controlled drug release that may enhance therapeutic effectiveness and reduce systemic toxicity. Light, an external stimulus, is one of the most promising triggers for use in nanomedicine to stimulate on-demand drug release from nanocarriers. Light-triggered drug release can be achieved through light irradiation at different wavelengths, either in the UV, visible, or even NIR region, depending on the photophysical properties of the photo-responsive molecule embedded in the nanocarrier system, the structural characteristics, and the material composition of the nanocarrier system. In this review, we highlighted the emerging functional role of light in nanocarriers, with an emphasis on light-responsive liposomes and dual-targeted stimuli-responsive liposomes. Moreover, we provided the most up-to-date photo-triggered targeting strategies and mechanisms of light-triggered drug release from liposomes and NIR-responsive nanocarriers. Lastly, we addressed the current challenges, advances, and future perspectives for the deployment of light-responsive liposomes in targeted drug delivery and therapy.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Liposomas/uso terapéutico , Portadores de Fármacos/química , Nanopartículas/química , Sistemas de Liberación de Medicamentos , Neoplasias/tratamiento farmacológico
10.
Environ Pollut ; 345: 123504, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38325509

RESUMEN

Low glyphosate doses that produce hormesis may alter the susceptibility to herbicides of weeds or enhance their propagation and dispersal. The objective of this work was to evaluate the hormetic effects of glyphosate on the vegetative, phenological and reproductive development in resistant (R) and susceptible (S) Conyza sumatrensis biotypes. The glyphosate resistance level of biotype R was 11.2-fold compared to the S biotype. Glyphosate doses <11.25 g ae ha-1 induced temporary and permanent hormetic effects for the number of leaves, plant height and dry mass accumulation up to 28 d after application in both R and S biotypes. The S biotype required 15-19% fewer thermal units at 1.4 and 2.8 g ae ha-1 glyphosate than untreated plants to reach the bolting stage. Also, this biotype had less thermal units associated with the appearance (1225 vs 1408 units) and opening (1520 vs 1765 units) of the first capitulum than the R biotype. In addition, glyphosate affected reproductive traits of both biotypes compared to their controls, increasing the number of capitulum's and seeds per plant up to 37 and 41% (at 2.8 and 0.7 g ae h-1, respectively) in the S biotype, and by 48 and 114% (both at 5.6 g ae ha-1) in the R biotype. Depending on environmental parameters, glyphosate may or may not cause hormetic effects on the vegetative and phenological development of C. sumatrenis biotypes; however, this herbicide increases the speed and fecundity of reproduction, regardless of the glyphosate susceptibility level, which can alter the population dynamics and glyphosate susceptibility of future generations.


Asunto(s)
Conyza , Herbicidas , Glifosato , Glicina/toxicidad , Hormesis , Resistencia a los Herbicidas , Herbicidas/toxicidad , Plantas
11.
CoDAS ; 36(1): e20220341, 2024. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1514026

RESUMEN

ABSTRACT Purpose Due to the pandemic of the Covid-19 disease, it became common to wear masks on some public spaces. By covering mouth and nose, visual-related speech cues are greatly reduced, while the auditory signal is both distorted and attenuated. The present study aimed to analyze the multisensory effects of mask wearing on speech intelligibility and the differences in these effects between participants who spoke 1, 2 and 3 languages. Methods The study consisted of the presentation of sentences from the SPIN test to 40 participants. Participants were asked to report the perceived sentences. There were four conditions: auditory with mask; audiovisual with mask; auditory without mask; audiovisual without mask. Two sessions were conducted, one week apart, each with the same stimuli but with a different signal-to-noise ratio. Results Results demonstrated that the use of the mask decreased speech intelligibility, both due to a decrease in the quality of auditory stimuli and due to the loss of visual information. Signal-to-noise ratio largely affects speech intelligibility and higher ratios are needed in mask-wearing conditions to obtain any degree of intelligibility. Those who speak more than one language are less affected by mask wearing, as are younger listeners. Conclusion Wearing a facial mask reduces speech intelligibility, both due to visual and auditory factors. Older people and people who only speak one language are affected the most.


RESUMO Objetivo Devido à pandemia da doença Covid-19, o uso de máscaras em espaços públicos tornou-se comum. Ao cobrir a boca e o nariz, reduzem-se amplamente as pistas visuais associadas à fala, assim como se distorce e atenua o sinal auditivo. Este estudo teve como objetivo analisar os efeitos multissensoriais do uso da máscara na percepção da fala e a diferença entre participantes falantes de uma, duas ou três línguas. Método Este estudo consistiu na apresentação de frases do SPIN teste a 40 participantes. Os participantes tinham como tarefa reportar as frases percebidas em quatro condições: Auditiva com máscara, audiovisual com máscara, auditiva sem máscara, audiovisual sem máscara. Conduziram-se duas sessões, com uma semana de intervalo, cada uma com os mesmos estímulos mas com diferente relação sinal-ruído. Resultados Os resultados demonstraram que o uso de máscara reduz a inteligibilidade da fala, tanto devido à diminuição da qualidade do estímulo auditivo, como devido à perda de informação visual. A relação sinal-ruído afeta a inteligibilidade e com o uso de máscara são necessárias relações mais altas para obter qualquer identificação correta. Aqueles que falam mais do que uma língua, assim como os mais novos, são menos afetados na percepção de fala com uso de máscara. Conclusão O uso de máscara facial reduz a inteligibilidade da fala, tanto devido a fatores visuais como auditivos. Indivíduos monolíngues, assim como os mais velhos, são os mais afetados nesta tarefa.

12.
Pharmaceutics ; 15(12)2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38140084

RESUMEN

Additive manufacturing, widely known as 3D printing, has revolutionized the production of biomaterials. While conventional 3D-printed structures are perceived as static, 4D printing introduces the ability to fabricate materials capable of self-transforming their configuration or function over time in response to external stimuli such as temperature, light, or electric field. This transformative technology has garnered significant attention in the field of biomedical engineering due to its potential to address limitations associated with traditional therapies. Here, we delve into an in-depth review of 4D-printing systems, exploring their diverse biomedical applications and meticulously evaluating their advantages and disadvantages. We emphasize the novelty of this review paper by highlighting the latest advancements and emerging trends in 4D-printing technology, particularly in the context of biomedical applications.

13.
J Fungi (Basel) ; 9(12)2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-38132736

RESUMEN

Beauveria bassiana is a dimorphic and entomopathogenic fungus with different ecological roles in nature. In pathogenic fungi, yeast-to-mycelial conversion, which is controlled by environmental factors, is required for virulence. Here, we studied the effects of different stimuli on the morphology of two B. bassiana strains and compared the toxicities of culture filtrates. In addition, we explored the role of volatiles as quorum sensing-like signals during dimorphic transition. The killing assays in Caenorhabditis elegans (Nematoda: Rhabditidae) showed that strain AI2 isolated from a mycosed insect cadaver had higher toxicity than strain AS5 isolated from soil. Furthermore, AI2 showed earlier yeast-to-mycelial switching than AS5. However, an increase in inoculum size induced faster yeast-to-mycelium conversion in AS5 cells, suggesting a cell-density-dependent phenomenon. Gas chromatography-mass spectrometry (GC-MS) analyses showed that the fingerprint of the volatiles was strain-specific; however, during the morphological switching, an inverse relationship between the abundance of total terpenes and 3-methylbutanol was observed in both strains. Fungal exposure to 3-methylbutanol retarded the yeast-to-mycelium transition. Hence, this study provides evidence that volatile compounds are associated with critical events in the life cycle of B. bassiana.

14.
Polymers (Basel) ; 15(21)2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37959981

RESUMEN

Electrospun nanofibrous membranes have garnered significant attention in antimicrobial applications, owing to their intricate three-dimensional network that confers an interconnected porous structure, high specific surface area, and tunable physicochemical properties, as well as their notable capacity for loading and sustained release of antimicrobial agents. Tailoring polymer or hybrid-based nanofibrous membranes with stimuli-responsive characteristics further enhances their versatility, enabling them to exhibit broad-spectrum or specific activity against diverse microorganisms. In this review, we elucidate the pivotal advancements achieved in the realm of stimuli-responsive antimicrobial electrospun nanofibers operating by light, temperature, pH, humidity, and electric field, among others. We provide a concise introduction to the strategies employed to design smart electrospun nanofibers with antimicrobial properties. The core section of our review spotlights recent progress in electrospun nanofiber-based systems triggered by single- and multi-stimuli. Within each stimulus category, we explore recent examples of nanofibers based on different polymers and antimicrobial agents. Finally, we delve into the constraints and future directions of stimuli-responsive nanofibrous materials, paving the way for their wider application spectrum and catalyzing progress toward industrial utilization.

15.
Nucl Med Biol ; 126-127: 108390, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37804561

RESUMEN

This study aimed to evaluate the repeatability of brown adipose tissue (BAT) activation measured by [18F]FDG-PET after beta3-adrenergic stimuli with CL316243 in mice. METHODS: Male C57BL/6 mice underwent [18F]FDG-PET at baseline without stimulation (T0-NS), on three consecutive days after intravenous administration of the selective ß3-adrenergic agonist CL316243 (T1-CL, T2-CL, T3-CL), and without stimuli after 1 and 2 weeks (T7-NS and T14-NS). The standardized uptake value (SUVmax), BAT metabolic volume (BMV), and total BAT glycolysis (TBG) were measured in each scanning session, with statistical groupwise comparisons by ANOVA and post hoc Tukey test. RESULTS: SUVmax, BMV, and TBG values showed no significant differences between the three PET scans without stimuli, but were significantly higher after CL316243 administration (p < 0.0001). The mean coefficient of variation (CoV) of PET within individuals was 49 % at baseline but only 9 % with pharmacological stimulation. CONCLUSIONS: The study demonstrated that administration of the selective ß3-adrenergic receptor agonist CL316243 (CL) in mice leads to consistent metabolic activation of brown adipose tissue (BAT), as measured by [18F]FDG-PET. We also demonstrated metabolic activation by repeated pharmacological challenge, without evidence of hysteresis. Thus, the methods used in the current work should serve for further studies on BAT metabolism in experimental animals, with translational value for clinical research.


Asunto(s)
Tejido Adiposo Pardo , Fluorodesoxiglucosa F18 , Masculino , Ratones , Animales , Fluorodesoxiglucosa F18/metabolismo , Tejido Adiposo Pardo/diagnóstico por imagen , Adrenérgicos/metabolismo , Adrenérgicos/farmacología , Ratones Endogámicos C57BL , Tomografía de Emisión de Positrones/métodos , Modelos Animales de Enfermedad , Tejido Adiposo/metabolismo
16.
J Exp Anal Behav ; 120(3): 394-405, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37710382

RESUMEN

Empirical evidence has supported that musical excerpts written in major and minor modes are responsible for evoking happiness and sadness, respectively. In this study, we evaluated whether the emotional content evoked by musical stimuli would transfer to abstract figures when they became members of the same equivalence class. Participants assigned to the experimental group were submitted to a training procedure to form equivalence classes comprising musical excerpts (A) and meaningless abstract figures (B, C, and D). Afterward, transfer of function was evaluated using a semantic differential. Participants in the control group showed positive semantic differential scores for major mode musical excerpts, negative scores for minor mode musical excerpts, and neutral scores for the B, C, and D stimuli. Participants in the experimental groups showed positive semantic differential scores for visual stimuli equivalent to the major modes and negative semantic differential scores for visual stimuli equivalent to the minor modes. These results indicate transfer of function of emotional content present in musical stimuli through equivalence class formation. These findings could provide a more comprehensive understanding of the effects of using emotional stimuli in equivalence class formation experiments and in transfer of function itself.


Asunto(s)
Aprendizaje Discriminativo , Música , Humanos
17.
Brain Sci ; 13(6)2023 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-37371383

RESUMEN

Naturalistic paradigms are being increasingly applied to investigate human brain function. Compared with resting-state and task-based paradigms in neuroimaging, naturalistic stimuli and situations can be potentially more readily translated to daily-life applications. Among neuroimaging modalities, functional near-infrared spectroscopy (fNIRS) is particularly suitable for naturalistic investigations and applications. However, specific and tailored statistical analysis to interrogate brain function using naturalistic fNIRS is warranted. Here, we describe an exploratory graph-centrality-based approach to investigating participants' spatiotemporal similarities from the fNIRS signal. We illustrate the usefulness of our approach in a sample of typically developing children (10 males and 9 females; mean age of 5.2 years old; sd = 0.78) while they watch the Inscapes movie designed for neuroimaging acquisition. A node in the left dorsal prefrontal cortex presented similar responses across children, and those fNIRS responses were in line with scene transitions in the movie stimulus. Our results suggest the feasibility of applying centrality graph-based measures to investigate brain function in naturalistic fNIRS during development.

18.
Behav Brain Res ; 447: 114398, 2023 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-36966939

RESUMEN

Social cues are valuable sensorial stimuli to the acquisition and retrieval of contextual memories. Here, we asked whether the valence of social cues would impact the formation of contextual memories. Adult male C57/BL6 mice were exposed to either conditioned place preference (CPP) or avoidance (CPA). As positive stimuli we used social interaction with a female (IF), while interaction with a male CD1 mice (IM) was used as negative stimulus. Contextual memory was tested 24 h and 7 days after conditioning. Aggressive behavior of CD1, as well as interaction with the female were quantified along the conditioning sessions. IM, but not IF, was salient enough to induce contextual memory estimated by the difference between the time in the conditioned context during test and habituation. Next, we chose two odors with innate behavioral responses and opposite valence to narrow down the sociability to one of its sensorial sources of information - the olfaction. We used urine from females in proestrus (U) and 2,4,5-trimethyl thiazoline (TMT), a predator odor. TMT decreased and U increased the time in the conditioned context during the test performed 24 h and 7 days after conditioning. Taken together, our results suggest that contextual memories conditioned to social encounters are difficult to stablish in mice, specially the one with positive valence. On the other hand, using odors with ecological relevance is a promising strategy to study long-term contextual memories with opposite valences. Ultimately, the behavioral protocol proposed here offers the advantage of studying contextual memories with opposite valences using unconditioned stimulus from the same sensorial category such as olfaction.


Asunto(s)
Condicionamiento Clásico , Señales (Psicología) , Masculino , Ratones , Femenino , Animales , Condicionamiento Clásico/fisiología , Condicionamiento Operante , Memoria a Largo Plazo , Odorantes
19.
Front Hum Neurosci ; 16: 909939, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35966986

RESUMEN

Interpersonal coordination requires precise actions concerted in space and time in a self-organized manner. We found, using soccer teams as a testing ground, that a common timeframe provided by adequate acoustic stimuli improves the interplay between teammates. We provide quantitative evidence that the connectivity between teammates and the scoring rate of male soccer teams improve significantly when playing under the influence of an appropriate acoustic environment. Unexpectedly, female teams do not show any improvement under the same experimental conditions. We show by follow-up experiments that the acoustic rhythm modulates the attention level of the participants with a pronounced tempo preference and a marked gender difference in the preferred tempo. These results lead to a consistent explanation in terms of the dynamical system theory, nonlinear resonances, and dynamic attention theory, which may illuminate generic mechanisms of the brain dynamics and may have an impact on the design of novel training strategies in team sports.

20.
J Econ Entomol ; 115(4): 1156-1163, 2022 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-35796144

RESUMEN

Alphitobius diaperinus is one of the most significant pests in the poultry industry. Identifying the role of self-produced chemical signals can help control it. Here, we exposed adults to the olfactory signals of other adults of similar and different genders (either males or females) and sexual experiences (i.e., virgin and experienced) to assess their long-range attractiveness and, at short-range, their mating behavior responses (i.e., touching, mounting, and copulation). In olfactometric experiments, our results indicate that adults are attracted to the olfactory signals of other male adults, independently of gender, or sexual condition, indicating the presence of generalized long-range attractive signals, in contrast to female signals, can be both factor-dependent. However, in mating experiments, virgin males developed more robust mating responses (i.e., they mount and copulate longer with females) compared to sexually experienced males, even though they both have similar precopulatory behavioral responses (i.e., time of antennal and leg touching). These results address the importance of short-range chemical signals in eliciting copulation. Furthermore, when virgins of both genders were tested, their mating responses were significantly longer than any other pair combination, indicating that sexual experience also affects mating behavior. Chemical analyses of adult extracts showed that sexual experience, but not gender, is linked to differences in chemical profiles of adults, primarily involved in short-range signaling. These findings provide new insights into the attractiveness and mating responses of A. diaperinus and the role of sexual experience in shaping the behavior and chemical profile of insects that mate multiple times during their lifetime.


Asunto(s)
Escarabajos , Animales , Escarabajos/fisiología , Femenino , Masculino , Aves de Corral , Reproducción , Conducta Sexual Animal/fisiología
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