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1.
Exp Brain Res ; 241(7): 1905-1917, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37349405

RESUMO

This study investigates whether and how parent's cooperation affects child's cooperation, and whether that differs between children with/without autism spectrum disorder (ASD). The experiment involved a cooperative key-pressing task completed first by parent-parent dyads and then by parent-child dyads, meanwhile brain activity in the right frontal-parietal cortex of dyad partners was measured synchronously. The results showed the following: ASD children exhibited performance comparable to those of their peers, as was the level of brain synchronization with their parents, which was mainly due to parents with ASD children tending to adjust their own response patterns to match those of their children. These findings suggest that parents can somewhat actively mitigate the lower interpersonal synchronization ability of ASD children, in behavioral or/and neural level.


Assuntos
Transtorno do Espectro Autista , Humanos , Pais , Encéfalo , Lobo Frontal , Relações Pais-Filho
2.
Brain Cogn ; 168: 105972, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37079997

RESUMO

Pain elicits the desire for a reward to alleviate the unpleasant sensation. This may be a consequence of facilitated neural activities in the reward circuit. However, the temporal modulation of pain on reward processing remains unclear. We addressed this issue by recording electroencephalogram when participants received win or loss feedback in a simple gambling task. Pain treatment was conducted on 33 participants with topical capsaicin cream and on 33 participants with hand cream as a control. Results showed that pain generally increased the P300 amplitude for both types of feedback but did not affect feedback-related negativity (FRN). A significant interaction effect of treatment (painful, non-painful) and outcome (win, loss) was observed on delta oscillation as pain only enhanced the power of win feedback. In addition, the FRN and theta oscillation responded more to loss feedback, but this effect was unaffected by pain. These findings indicate that pain may enhance secondary value representation and evaluation processes of rewards, but does not influence primary distinction of reward or reward expectation. The temporal unfolding of how pain affects reward-related neural activities highlights the prominent impact of pain on high-level cognitive processes associated with reward.


Assuntos
Potenciais Evocados , Jogo de Azar , Humanos , Eletroencefalografia , Recompensa , Jogo de Azar/psicologia , Dor , Retroalimentação Psicológica
3.
Hum Brain Mapp ; 41(5): 1372-1381, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31785068

RESUMO

Pain has been found to promote reward-seeking behaviors, which might be a consequence of modulated brain activities in the reward neural circuitry in a painful state. The present study investigated how pain affected reward processing and reward-related neural activities using fMRI technique. A total of 50 healthy participants were recruited and used for data analyses, with half being treated with topical capsaicin cream and the other half with hand cream (treatment: pain or control). The participants were asked to perform a card-guessing game when their brain activities responding to feedbacks (outcome: win or loss) were recorded. Behavioral results showed that participants in pain group overestimated their correct choices in the card-guess game. Whole-brain fMRI analysis revealed that the main effect of outcome (win vs. loss) activated a typical network of the reward neural circuitry, including the medial prefrontal cortex (mPFC) and the bilateral nucleus accumbens (NAcc). Importantly, the region of interest analysis revealed a significant interaction of treatment and outcome in the mPFC, with increased mPFC neural activity responding to win outcome in pain condition. Moreover, the functional connectivity between the mPFC and the NAcc was decreased in pain condition. We conclude that the pain-induced modulation of the mPFC activity could result in alterations of both the emotional response to and the cognitive evaluation of reward.


Assuntos
Dor/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Recompensa , Mapeamento Encefálico , Capsaicina , Retroalimentação Psicológica , Feminino , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Núcleo Accumbens/diagnóstico por imagem , Núcleo Accumbens/fisiopatologia , Oxigênio/sangue , Dor/induzido quimicamente , Dor/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Psicofísica , Autoimagem , Adulto Jovem
4.
Hum Brain Mapp ; 40(11): 3222-3232, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30950151

RESUMO

Individuals in pain are motivated to be cooperative in social interaction. Yet, there has been little research on how pain dynamically affects cooperation at a neural level. The present study investigated the cooperative behavior under acute physical pain by asking dyads to complete three blocks of button-press cooperative task, while neural activities were recorded simultaneously on each subject by the fNIRS-based hyperscanning. Results showed that individuals in pain improved their cooperation rate across task blocks. Accordingly, increased interpersonal neural synchronization (INS) was found at the left prefrontal cortex in second block, whereas increased INS was found at the right prefrontal cortex and the right parietal cortex in third block compared to the first block. Moreover, the change of INS in right parietal cortex was positively correlated with subjective pain rating in the pain treatment group. In addition, dynamic interpersonal neural networks were identified in painful condition with increasing frontoparietal networks across time. By uncovering dissociative neural processes involved in how pain affects cooperation in social interaction, the present work provides the first interbrain evidence to highlight the sociality of pain on social interaction in perspective of motivational aspect of pain.


Assuntos
Encéfalo/diagnóstico por imagem , Comportamento Cooperativo , Rede Nervosa/diagnóstico por imagem , Dor/diagnóstico por imagem , Adolescente , Feminino , Neuroimagem Funcional , Humanos , Relações Interpessoais , Dor/psicologia , Medição da Dor , Espectroscopia de Luz Próxima ao Infravermelho , Adulto Jovem
5.
Proc Natl Acad Sci U S A ; 113(33): 9256-61, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27482087

RESUMO

Humans update their beliefs upon feedback and, accordingly, modify their behaviors to adapt to the complex, changing social environment. However, people tend to incorporate desirable (better than expected) feedback into their beliefs but to discount undesirable (worse than expected) feedback. Such optimistic updating has evolved as an advantageous mechanism for social adaptation. Here, we examine the role of oxytocin (OT)-an evolutionary ancient neuropeptide pivotal for social adaptation-in belief updating upon desirable and undesirable feedback in three studies (n = 320). Using a double-blind, placebo-controlled between-subjects design, we show that intranasally administered OT (IN-OT) augments optimistic belief updating by facilitating updates of desirable feedback but impairing updates of undesirable feedback. The IN-OT-induced impairment in belief updating upon undesirable feedback is more salient in individuals with high, rather than with low, depression or anxiety traits. IN-OT selectively enhances learning rate (the strength of association between estimation error and subsequent update) of desirable feedback. IN-OT also increases participants' confidence in their estimates after receiving desirable but not undesirable feedback, and the OT effect on confidence updating upon desirable feedback mediates the effect of IN-OT on optimistic belief updating. Our findings reveal distinct functional roles of OT in updating the first-order estimation and second-order confidence judgment in response to desirable and undesirable feedback, suggesting a molecular substrate for optimistic belief updating.


Assuntos
Cultura , Retroalimentação Psicológica , Ocitocina/farmacologia , Administração Intranasal , Ansiedade/psicologia , Depressão/psicologia , Método Duplo-Cego , Humanos , Julgamento , Aprendizagem/efeitos dos fármacos , Masculino , Ajustamento Social
6.
Nature ; 479(7371): 88-93, 2011 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-22051677

RESUMO

Many natural products contain a C = C double bond through which various other derivatives can be prepared; the stereochemical identity of the alkene can be critical to the biological activities of such molecules. Catalytic ring-closing metathesis (RCM) is a widely used method for the synthesis of large unsaturated rings; however, cyclizations often proceed without control of alkene stereochemistry. This shortcoming is particularly costly when the cyclization reaction is performed after a long sequence of other chemical transformations. Here we outline a reliable, practical and general approach for the efficient and highly stereoselective synthesis of macrocyclic alkenes by catalytic RCM; transformations deliver up to 97% of the Z isomer owing to control induced by a tungsten-based alkylidene. Utility is demonstrated through the stereoselective preparation of epothilone C (refs 3-5) and nakadomarin A (ref. 6), the previously reported syntheses of which have been marred by late-stage, non-selective RCM. The tungsten alkylidene can be manipulated in air, delivering the products in useful yields with high stereoselectivity. As a result of efficient RCM and re-incorporation of side products into the catalytic cycle with minimal alkene isomerization, desired cyclizations proceed in preference to alternative pathways, even under relatively high substrate concentration.


Assuntos
Produtos Biológicos/síntese química , Técnicas de Química Sintética/métodos , Alcanos/química , Alcenos/química , Produtos Biológicos/química , Carbolinas/síntese química , Carbolinas/química , Catálise , Ciclização , Epotilonas/síntese química , Epotilonas/química , Estereoisomerismo
7.
Neuroimage ; 135: 186-96, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27132044

RESUMO

Humans exhibit substantial inter-individual differences in pain perception, which contributes to variability in analgesic efficacy. Individual differences in pain sensitivity have been linked with variation in the serotonin transporter gene (5-HTTLPR), and selective serotonin reuptake inhibitors (SSRIs) such as citalopram have been increasingly used as treatments for multiple pain conditions. We combined genotyping, pharmacological challenge, and neuroimaging during painful electrical stimulation to reveal how serotonin genetics and pharmacology interact to influence pain perception and its underlying neurobiological mechanisms. In a double-blind, placebo-controlled procedure, we acutely administrated citalopram (30mgpo) to short/short (s/s) and long/long (l/l) healthy male 5-HTTLPR homozygotes during functional MRI with painful and non-painful electrical stimulation. 5-HTTLPR genotype modulated citalopram effects on pain-related brain responses in the thalamus, cerebellum, anterior insula, midcingulate cortex and inferior frontal cortex. Specifically, citalopram significantly reduced pain-related brain responses in l/l but not in s/s homozygotes. Moreover, the interaction between 5-HTTLPR genotype and pain-related brain activity was a good predictor of the citalopram-induced reductions in pain reports. The genetic modulations of citalopram effects on brain-wide pain processing were paralleled by significant effects on the Neurological Pain Signature, a multivariate brain pattern validated to be sensitive and specific to physical pain. This work provides neurobiological mechanism by which genetic variation shapes brain responses to pain perception and treatment efficacy. These findings have important implications for the types of individuals for whom serotonergic treatments provide effective pain relief, which is critical for advancing personalized pain treatment.


Assuntos
Citalopram/administração & dosagem , Percepção da Dor/efeitos dos fármacos , Limiar da Dor/efeitos dos fármacos , Polimorfismo de Nucleotídeo Único/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Analgésicos/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Masculino , Medição da Dor/efeitos dos fármacos , Testes Farmacogenômicos/métodos , Efeito Placebo , Inibidores Seletivos de Recaptação de Serotonina/administração & dosagem , Resultado do Tratamento , Adulto Jovem
8.
Br J Psychiatry ; 206(5): 385-92, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25745133

RESUMO

BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs), such as citalopram, which selectively block serotonin transporter (5-HTT) activity, are widely used in the treatment of depression and anxiety disorders. Numerous neuroimaging studies have examined the effects of SSRIs on emotional processes. However, there are considerable inter-individual differences in SSRI effect, and a recent meta-analysis further revealed discrepant effects of acute SSRI administration on neural responses to negative emotions in healthy adults. AIMS: We examined how a variant of the serotonin-transporter polymorphism (5-HTTLPR), which affects the expression and function of 5-HTT, influenced the acute effects of an SSRI (citalopram) on emotion-related brain activity in healthy adults. METHOD: Combining genetic neuroimaging, pharmacological technique and a psychological paradigm of emotion recognition, we scanned the short/short (s/s) and long/long (l/l) variants of 5-HTTLPR during perception of fearful, happy and neutral facial expressions after the acute administration of an SSRI (i.e. 30 mg citalopram administered orally) or placebo administration. RESULTS: We found that 5-HTTLPR modulated the acute effects of citalopram on neural responses to negative emotions. Specifically, relative to placebo, citalopram increased amygdala and insula activity in l/l but not s/s homozygotes during perception of fearful faces. Similar analyses of brain activity in response to happy faces did not show any significant effects. CONCLUSIONS: Our combined pharmacogenetic and functional imaging results provide a neurogenetic mechanism for discrepant acute effects of SSRIs.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Citalopram/administração & dosagem , Emoções/efeitos dos fármacos , Rede Nervosa/efeitos dos fármacos , Inibidores Seletivos de Recaptação de Serotonina/administração & dosagem , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Adolescente , Alelos , Expressão Facial , Medo/efeitos dos fármacos , Voluntários Saudáveis , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
9.
Cereb Cortex ; 24(9): 2421-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23588187

RESUMO

Cognitive distortion in depression is characterized by enhanced negative thoughts about both environment and oneself. Carriers of a risk allele for depression, that is, the short (s) allele of the serotonin transporter promoter polymorphism (5-HTTLPR), exhibit amygdala hyperresponsiveness to negative environmental stimuli relative to homozygous long variant (l/l). However, the neural correlates of negative self-schema in s allele carriers remain unknown. Using functional MRI, we scanned individuals with s/s or l/l genotype of the 5-HTTLPR during reflection on their own personality traits or a friend's personality traits. We found that relative to l/l carriers, s/s carriers showed stronger distressed feelings and greater activity in the dorsal anterior cingulate (dACC)/dorsal medial prefrontal cortex (dmPFC) and the right anterior insula (AI) during negative self-reflection. The 5-HTTLPR effect on the distressed feelings was mediated by the AI/inferior frontal (IF) activity during negative self-reflection. The dACC/dmPFC activity explained 20% of the variation in harm-avoidance tendency in s/s but not l/l carriers. The genotype effects on distress and brain activity were not observed during reflection on a friend's negative traits. Our findings reveal that 5-HTTLPR polymorphism modulates distressed feelings and brain activities associated with negative self-schema and suggest a potential neurogenetic susceptibility mechanism for depression.


Assuntos
Encéfalo/fisiologia , Polimorfismo Genético , Autoimagem , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Mapeamento Encefálico , Feminino , Amigos , Técnicas de Genotipagem , Humanos , Julgamento/fisiologia , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiologia , Testes Neuropsicológicos , Oxigênio/sangue , Personalidade , Adulto Jovem
10.
ScientificWorldJournal ; 2014: 797814, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25133260

RESUMO

Assessment of ecoenvironmental vulnerability plays an important role in the guidance of regional planning, the construction and protection of ecological environment, which requires comprehensive consideration on regional resources, environment, ecology, society and other factors. Based on the driving mechanism and evolution characteristics of ecoenvironmental vulnerability in cold and arid regions of China, a novel evaluation index system on ecoenvironmental vulnerability is proposed in this paper. For the disadvantages of conventional entropy weight method, an improved entropy weight assessment model on ecoenvironmental vulnerability is developed and applied to evaluate the ecoenvironmental vulnerability in western Jilin Province of China. The assessing results indicate that the model is suitable for ecoenvironmental vulnerability assessment, and it shows more reasonable evaluation criterion, more distinct insights and satisfactory results combined with the practical conditions. The model can provide a new method for regional ecoenvironmental vulnerability evaluation.


Assuntos
Entropia , Monitoramento Ambiental/métodos , Modelos Teóricos , China
11.
Int J Nanomedicine ; 19: 6295-6317, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38919774

RESUMO

Nanoscale metal-organic frameworks (MOFs) offer high biocompatibility, nanomaterial permeability, substantial specific surface area, and well-defined pores. These properties make MOFs valuable in biomedical applications, including biological targeting and drug delivery. They also play a critical role in tumor diagnosis and treatment, including tumor cell targeting, identification, imaging, and therapeutic methods such as drug delivery, photothermal effects, photodynamic therapy, and immunogenic cell death. The diversity of MOFs with different metal centers, organics, and surface modifications underscores their multifaceted contributions to tumor research and treatment. This review is a summary of these roles and mechanisms. The final section of this review summarizes the current state of the field and discusses prospects that may bring MOFs closer to pharmaceutical applications.


Assuntos
Estruturas Metalorgânicas , Nanocompostos , Neoplasias , Estruturas Metalorgânicas/química , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Nanocompostos/química , Nanocompostos/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Animais , Fotoquimioterapia/métodos , Antineoplásicos/química , Nanomedicina/métodos
12.
Chemistry ; 19(8): 2726-40, 2013 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-23345004

RESUMO

The first broadly applicable set of protocols for efficient Z-selective formation of macrocyclic disubstituted alkenes through catalytic ring-closing metathesis (RCM) is described. Cyclizations are performed with 1.2-7.5 mol% of a Mo- or W-based monoaryloxide pyrrolide (MAP) complex at 22 °C and proceed to complete conversion typically within two hours. Utility is demonstrated by synthesis of representative macrocyclic alkenes, such as natural products yuzu lactone (13-membered ring: 73% Z) epilachnene (15-membered ring: 91% Z), ambrettolide (17-membered ring: 91% Z), an advanced precursor to epothilones C and A (16-membered ring: up to 97% Z), and nakadomarin A (15-membered ring: up to 97% Z). We show that catalytic Z-selective cyclizations can be performed efficiently on gram-scale with complex molecule starting materials and catalysts that can be handled in air. We elucidate several critical principles of the catalytic protocol: 1) The complementary nature of the Mo catalysts, which deliver high activity but can be more prone towards engendering post-RCM stereoisomerization, versus W variants, which furnish lower activity but are less inclined to cause loss of kinetic Z selectivity. 2) Reaction time is critical to retaining kinetic Z selectivity not only with MAP species but with the widely used Mo bis(hexafluoro-tert-butoxide) complex as well. 3) Polycyclic structures can be accessed without significant isomerization at the existing Z alkenes within the molecule.


Assuntos
Alcaloides/síntese química , Produtos Biológicos/síntese química , Hidrocarbonetos Aromáticos com Pontes/síntese química , Carbolinas/síntese química , Cicloparafinas/síntese química , Epotilonas/síntese química , Lactonas/síntese química , Compostos Macrocíclicos/síntese química , Molibdênio/química , Rutênio/química , Alcaloides/química , Produtos Biológicos/química , Hidrocarbonetos Aromáticos com Pontes/química , Carbolinas/química , Catálise , Ciclização , Cicloparafinas/química , Epotilonas/química , Cinética , Lactonas/química , Compostos Macrocíclicos/química , Estrutura Molecular , Estereoisomerismo
13.
Soc Cogn Affect Neurosci ; 18(1)2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35894605

RESUMO

Physical pain may lead to aggressive behavior in a social context. However, it is unclear whether this is related to changes of social information processing. Thus, this study aimed to investigate the neural mechanisms underlying pain-induced aggression using functional magnetic resonance imaging. In the experiment, 59 healthy participants were recruited: 31 were treated with topical capsaicin cream (pain group) and 28 with hand cream (control group). Participants completed a social network aggression task, during which they underwent two phases: feedback processing and attack exerting. The results revealed that participants in the pain group exhibited more aggression than those in the control group. During the feedback-processing phase, physical pain reduced brain activation in the right insula, left orbitofrontal cortex and anterior cingulate cortex, which typically exhibited stronger activation in response to negative (and positive) vs neutral social feedback in the control group. However, during the attack-exerting phase, pain did not significantly alter the activation of the dorsolateral prefrontal cortex. These findings suggest that pain increased aggression, while before that, it suppressed brain activities of the salience network involved in the process of salient social information and the value system associated with the value representation of social events.


Assuntos
Agressão , Encéfalo , Humanos , Retroalimentação , Agressão/fisiologia , Encéfalo/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Mapeamento Encefálico , Dor , Imageamento por Ressonância Magnética/métodos
14.
ACS Catal ; 13(14): 9558-9566, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37497376

RESUMO

Single-site catalysts (SSCs) have attracted significant research interest due to their high metal atom utilization. Platinum single sites trapped in the defects of carbon substrates (trapped Pt-SSCs) have been proposed as efficient and stable electrocatalysts for the hydrogen evolution reaction (HER). However, the correlation between Pt bonding environment, its evolution during operation, and catalytic activity is still unclear. Here, a trapped Pt-SSC is synthesized by pyrolysis of H2PtCl6 chemisorbed on a polyaniline substrate. In situ heated scanning transmission electron microscopy and temperature-dependent X-ray photoelectron spectroscopy clarify the thermally induced structural evolution of Pt during pyrolysis. The results show that the nitrogen in polyaniline coordinates with Pt ions and atomically disperses them before pyrolysis and traps Pt sites at pyridinic N defects generated during the substrate graphitization. Operando X-ray absorption spectroscopy confirms that the trapped Pt-SSC is stable at the HER working potentials but with inferior electrocatalytic activity compared with metallic Pt nanoparticles. First principle calculations suggest that the inferior activity of trapped Pt-SSCs is due to their unfavorable hydrogen chemisorption energy relative to metallic Pt(111) surfaces. These results further the understanding of the structure-property relationship in trapped Pt-SSCs and motivate a detailed techno-economic analysis to evaluate their commercial applicability.

15.
ACS Catal ; 12(5): 3173-3180, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35558899

RESUMO

Platinum single-site catalysts (SSCs) are a promising technology for the production of hydrogen from clean energy sources. They have high activity and maximal platinum-atom utilization. However, the bonding environment of platinum during operation is poorly understood. In this work, we present a mechanistic study of platinum SSCs using operando, synchrotron-X-ray absorption spectroscopy. We synthesize an atomically dispersed platinum complex with aniline and chloride ligands onto graphene and characterize it with ex-situ electron microscopy, X-ray diffractometry, X-ray photoelectron spectroscopy, X-ray absorption near-edge structure spectroscopy (XANES), and extended X-ray absorption fine structure spectroscopy (EXAFS). Then, by operando EXAFS and XANES, we show that as a negatively biased potential is applied, the Pt-N bonds break first followed by the Pt-Cl bonds. The platinum is reduced from platinum(II) to metallic platinum(0) by the onset of the hydrogen-evolution reaction at 0 V. Furthermore, we observe an increase in Pt-Pt bonding, indicating the formation of platinum agglomerates. Together, these results indicate that while aniline is used to prepare platinum SSCs, the single-site complexes are decomposed and platinum agglomerates at operating potentials. This work is an important contribution to the understanding of the evolution of bonding environment in SSCs and provides some molecular insights into how platinum agglomeration causes the deactivation of SSCs over time.

16.
Neuroimage ; 57(3): 1273-80, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21596143

RESUMO

Empathy has been proposed to be a proximate mechanism underlying altruistic behavior. However, both empathy and altruistic behavior differ between human individuals with low and high socioeconomic status. Here we investigated whether subjective socioeconomic status (SSS) modulates the relationship between neural activity to perceived pain in others and human altruistic behaviors in a real-life situation. After being scanned using functional MRI while observing videos of others in pain, participants were invited to make an anonymous monetary donation to a charitable organization. Painful stimuli increased activity in the inferior frontal, insula and somatosensory cortices compared to non-painful stimuli. A hierarchical regression analysis revealed that neural responses to perceived pain predicted the amount of monetary donations with different patterns in high and low SSS individuals. Stronger neural responses to perceived pain were associated with greater monetary donations in high SSS individuals, whereas a reverse pattern was observed in low SSS individuals. Our results suggest that SSS moderates the functional role of empathy-related neural activity in predicting altruistic behavior. Empathy may follow different mechanisms involved in altruistic behaviors (e.g., donation) depending on the social environment.


Assuntos
Altruísmo , Mapeamento Encefálico , Encéfalo/fisiologia , Empatia/fisiologia , Adulto , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Dor , Fatores Socioeconômicos , Adulto Jovem
17.
Carbohydr Polym ; 263: 117950, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33858567

RESUMO

Under the assistance of 13C NMR and 1H-13C HSQC, we develop a novel 1H NMR assay for the substitution sites and degrees in hydroxypropyl chitosan (HPCS) by optimizing sample preparation and measurement method. We find that the chemical shift of HOD peak increases linearly with the increase of DCl concentration but declines with the rise of measurement temperature. According to the regression line, the HOD peak could be moved to a desired position of non-interference with other peaks by changing DCl concentration. Other DCl-responsive peaks are found and elucidated. Accordingly, the substitution fraction (NH2-substitution and OH-substitution) and the degree of acetylation are well discriminated and determined. The total molar degree of substitution (MS) obtained is basically consistent with those of elemental analysis and the existing NMR methods. This structural analysis is extendable to other amino-containing saccharides. The 1H NMR method could be used widely in acid-soluble polysaccharides and their derivatives.


Assuntos
Técnicas de Química Analítica/métodos , Quitosana/análise , Quitosana/química , Espectroscopia de Prótons por Ressonância Magnética/métodos , Acetilação , Quitosana/análogos & derivados , Temperatura , Água/química
18.
Brain Behav ; 10(9): e01768, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32710600

RESUMO

INTRODUCTION: Individuals may employ different strategies when cooperating with others. For example, when two participants are asked to press buttons simultaneously, they may press the buttons as quickly as possible (immediate response strategy) or press them in a delayed pattern (delayed response strategy). Despite recognition of interpersonal brain synchronization (IBS) as a fundamental neural mechanism of cooperation, it remains unclear how various strategies influence cooperative behavior and its neural activities. METHODS: To address this issue, 43 married couples were recruited to complete a button-press cooperative task, during which IBS was recorded by functional near-infrared spectroscopy hyperscanning. RESULTS: Behavioral results showed that couples who adopted a delayed response strategy performed better than those who adopted an immediate response strategy and those without any obvious strategy, and a new measure (cooperation coefficient) was used to index the level of cooperation. In addition, stronger IBS in the right frontal cortex was observed in the delayed response condition. The greater couples' perceived parenting stress, the more likely they were to perform well in tasks and the stronger their brain synchronization, since they tended to choose the delayed response strategy. CONCLUSION: The delayed response strategy may better unify dyad partners' response modes, trigger synchronized psychological processes, and enable their brains to become synchronized. The study extends understanding of cooperation by comparing the contributions of different strategies underlying cooperative behavior with corresponding neural evidence.


Assuntos
Mapeamento Encefálico , Relações Interpessoais , Encéfalo , Comportamento Cooperativo , Humanos , Espectroscopia de Luz Próxima ao Infravermelho
19.
Front Hum Neurosci ; 14: 569010, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33132882

RESUMO

BACKGROUND: The beneficial effects of acute exercise on executive function have been well-documented, but the influence of cardiorespiratory fitness on this effect requires further investigations, especially using imaging technique. This study aimed to examine the effects of cardiorespiratory fitness on acute exercise-induced changes on behavioral performance and on functional brain activation. METHOD: Based on their cardiorespiratory fitness level, 62 participants ranked in the top and bottom of the maximum oxygen consumption (VO2 max) were finally selected and allocated to high-fit group or low-fit group. Both groups were asked to complete the Stroop task after 30 min of aerobic exercise and chair-seated rest (control session). Among them, 26 participants were randomly selected and asked to undergo the Functional Magnetic Resonance Imaging (fMRI). RESULTS: Behavioral results showed that individuals responded significantly faster after exercise than those in the control session. The fMRI results revealed a significant interaction effects of Group by Session in brain regions including anterior cingulate cortex (ACC) and bilateral dorsal lateral prefrontal cortex (DLPFC). For the ACC, activation in the high-fit group was significantly decreased after aerobic exercise compared to those in the control session; whereas an increased activation was noticed in the low-fit group. Regarding to the bilateral DLPFC, activation in high-fit group was significantly decreased after exercise compared to those in the control session, while no significant differences were found in the low-fit group. In addition, for the post-exercise session, a significant positive correlations between activation of the ACC and left DLPFC in the high-fit group was observed. There was a significant negative correlation between activation of the ACC and reaction time in the congruent condition after exercise in the low-fit group. CONCLUSION: Findings further clarify the neurophysiological processes of acute exercise-induced changes in cognitive performance as they suggest that cardiorespiratory fitness is an important factor which influences changes in brain activation patterns in response to acute aerobic exercises.

20.
Org Lett ; 21(5): 1538-1541, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30779589

RESUMO

A ketene [2 + 2]-addition, an intramolecular aldol reaction, a Suzuki-Miyaura coupling, and a chemoselective lactam reduction were used to prepare a late-stage precursor of haouamine A. Exposure to acid led to a Grob-type fragmentation of the strained 3-aza[7]paracyclophane ring, followed by a tandem Pictet-Spengler reaction of the intermediate iminium ion and conversion to a novel 1,4a-propanocyclopenta[ b]pyridine. This cascade reaction might also be relevant for the mechanism of action of the natural product.


Assuntos
Aldeídos/química , Etilenos/química , Compostos Heterocíclicos de 4 ou mais Anéis/química , Cetonas/química , Piridinas/química , Estrutura Molecular
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