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1.
Physiol Plant ; 176(3): e14356, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38828569

RESUMO

Halophyte Halogeton glomeratus mostly grows in saline desert areas in arid and semi-arid regions and is able to adapt to adverse conditions such as salinity and drought. Earlier transcriptomic studies revealed activation of the HgS2 gene in the leaf of H. glomeratus seedlings when exposed to saline conditions. To identify the properties of HgS2 in H. glomeratus, we used yeast transformation and overexpression in Arabidopsis. Yeast cells genetically transformed with HgS2 exhibited K+ uptake and Na+ efflux compared with control (empty vector). Stable overexpression of HgS2 in Arabidopsis improved its resistance to salt stress and led to a notable rise in seed germination in salinity conditions compared to the wild type (WT). Transgenic Arabidopsis regulated ion homeostasis in plant cells by increasing Na+ absorption and decreasing K+ efflux in leaves, while reducing Na+ absorption and K+ efflux in roots. In addition, overexpression of HgS2 altered transcription levels of stress response genes and regulated different metabolic pathways in roots and leaves of Arabidopsis. These results offer new insights into the role of HgS2 in plants' salt tolerance.


Assuntos
Amaranthaceae , Arabidopsis , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Plantas Geneticamente Modificadas , Tolerância ao Sal , Amaranthaceae/genética , Amaranthaceae/fisiologia , Arabidopsis/genética , Arabidopsis/fisiologia , Germinação/genética , Germinação/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/fisiologia , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Raízes de Plantas/metabolismo , Potássio/metabolismo , Tolerância ao Sal/genética , Plantas Tolerantes a Sal/genética , Plantas Tolerantes a Sal/fisiologia , Plantas Tolerantes a Sal/metabolismo , Sódio/metabolismo , Cloreto de Sódio/farmacologia
2.
Int J Mol Sci ; 25(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-39000330

RESUMO

Drought stress is a major meteorological threat to crop growth and yield. Barley (Hordeum vulgare L.) is a vital cereal crop with strong drought tolerance worldwide. However, the underlying growth properties and metabolomic regulatory module of drought tolerance remains less known. Here, we investigated the plant height, spike length, effective tiller, biomass, average spikelets, 1000-grain weight, number of seeds per plant, grain weight per plant, ash content, protein content, starch content, cellulose content, and metabolomic regulation mechanisms of drought stress in barley. Our results revealed that the growth properties were different between ZDM5430 and IL-12 under drought stress at different growth stages. We found that a total of 12,235 metabolites were identified in two barley genotype root samples with drought treatment. More than 50% of these metabolites showed significant differences between the ZDM5430 and IL-12 roots. The Kyoto Encyclopedia of Genes and Genomes pathway analysis identified 368 differential metabolites mainly involved in starch and sucrose metabolism, the pentose phosphate pathway, pyrimidine metabolism, phenylalanine, tyrosine, and tryptophan biosynthesis in ZDM5430 under drought stress, whereas the different metabolites of IL-12 under drought stress related to starch and sucrose metabolism, the pentose phosphate pathway, 2-oxocarboxylic acid metabolism, cutin, suberine and wax biosynthesis, carbon metabolism, fatty acid biosynthesis, and C5-branched dibasic acid metabolism. These metabolites have application in the tricarboxylic cycle, the urea cycle, the met salvage pathway, amino acid metabolism, unsaturated fatty acid biosynthesis, phenolic metabolism, and glycolysis. On the other hand, the expression patterns of 13 genes related to the abovementioned bioprocesses in different barley genotypes roots were proposed. These findings afford an overview for the understanding of barley roots' metabolic changes in the drought defense mechanism by revealing the differently accumulated compounds.


Assuntos
Secas , Hordeum , Metabolômica , Hordeum/genética , Hordeum/metabolismo , Hordeum/crescimento & desenvolvimento , Hordeum/fisiologia , Metabolômica/métodos , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico , Metaboloma , Raízes de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/genética , Amido/metabolismo , Resistência à Seca
3.
Int J Mol Sci ; 24(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36902137

RESUMO

Nitrogen is one of the most important mineral elements for plant growth and development. Excessive nitrogen application not only pollutes the environment, but also reduces the quality of crops. However, are few studies on the mechanism of barley tolerance to low nitrogen at both the transcriptome and metabolomics levels. In this study, the nitrogen-efficient genotype (W26) and the nitrogen-sensitive genotype (W20) of barley were treated with low nitrogen (LN) for 3 days and 18 days, then treated with resupplied nitrogen (RN) from 18 to 21 days. Later, the biomass and the nitrogen content were measured, and RNA-seq and metabolites were analyzed. The nitrogen use efficiency (NUE) of W26 and W20 treated with LN for 21 days was estimated by nitrogen content and dry weight, and the values were 87.54% and 61.74%, respectively. It turned out to have a significant difference in the two genotypes under the LN condition. According to the transcriptome analysis, 7926 differentially expressed genes (DEGs) and 7537 DEGs were identified in the leaves of W26 and W20, respectively, and 6579 DEGs and 7128 DEGs were found in the roots of W26 and W20, respectively. After analysis of the metabolites, 458 differentially expressed metabolites (DAMs) and 425 DAMs were found in the leaves of W26 and W20, respectively, and 486 DAMs and 368 DAMs were found in the roots of W26 and W20, respectively. According to the KEGG joint analysis of DEGs and DAMs, it was discovered that glutathione (GSH) metabolism was the pathway of significant enrichment in the leaves of both W26 and W20. In this study, the metabolic pathways of nitrogen metabolism and GSH metabolism of barley under nitrogen were constructed based on the related DAMs and DEGs. In leaves, GSH, amino acids, and amides were the main identified DAMs, while in roots, GSH, amino acids, and phenylpropanes were mainly found DAMs. Finally, some nitrogen-efficient candidate genes and metabolites were selected based on the results of this study. The responses of W26 and W20 to low nitrogen stress were significantly different at the transcriptional and metabolic levels. The candidate genes that have been screened will be verified in future. These data not only provide new insights into how barley responds to LN, but also provide new directions for studying the molecular mechanisms of barley under abiotic stress.


Assuntos
Hordeum , Transcriptoma , Hordeum/genética , Nitrogênio/metabolismo , Metaboloma/genética , Perfilação da Expressão Gênica/métodos , Genótipo , Aminoácidos/metabolismo , Regulação da Expressão Gênica de Plantas
4.
Int J Mol Sci ; 24(19)2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37834288

RESUMO

Low phosphorus (LP) stress leads to a significant reduction in wheat yield, primarily in the reduction of biomass, the number of tillers and spike grains, the delay in heading and flowering, and the inhibition of starch synthesis and grouting. However, the differences in regulatory pathway responses to low phosphorus stress among different wheat genotypes are still largely unknown. In this study, metabolome and transcriptome analyses of G28 (LP-tolerant) and L143 (LP-sensitive) wheat varieties after 72 h of normal phosphorus (CK) and LP stress were performed. A total of 181 and 163 differentially accumulated metabolites (DAMs) were detected for G28CK vs. G28LP and L143CK vs. L143LP, respectively. Notably, the expression of pilocarpine (C07474) in G28CK vs. G28LP was significantly downregulated 4.77-fold, while the expression of neochlorogenic acid (C17147) in L143CK vs. L143LP was significantly upregulated 2.34-fold. A total of 4023 differentially expressed genes (DEGs) were acquired between G28 and L143, of which 1120 DEGs were considered as the core DEGs of LP tolerance of wheat after LP treatment. The integration of metabolomics and transcriptomic data further revealed that the LP tolerance of wheat was closely related to 15 metabolites and 18 key genes in the sugar and amino acid metabolism pathway. The oxidative phosphorylation pathway was enriched to four ATPases, two cytochrome c reductase genes, and fumaric acid under LP treatment. Moreover, PHT1;1, TFs (ARFA, WRKY40, MYB4, MYB85), and IAA20 genes were related to the Pi starvation stress of wheat roots. Therefore, the differences in LP tolerance of different wheat varieties were related to energy metabolism, amino acid metabolism, phytohormones, and PHT proteins, and precisely regulated by the levels of various molecular pathways to adapt to Pi starvation stress. Taken together, this study may help to reveal the complex regulatory process of wheat adaptation to Pi starvation and provide new genetic clues for further study on improving plant Pi utilization efficiency.


Assuntos
Plântula , Transcriptoma , Plântula/genética , Plântula/metabolismo , Triticum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilação da Expressão Gênica , Metaboloma/genética , Fósforo/metabolismo , Aminoácidos/metabolismo , Regulação da Expressão Gênica de Plantas
5.
Cereb Cortex ; 31(3): 1848-1860, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30535355

RESUMO

Attention and salience processing have been linked to the intrinsic between- and within-network dynamics of large-scale networks engaged in internal (default network [DN]) and external attention allocation (dorsal attention network [DAN] and salience network [SN]). The central oxytocin (OXT) system appears ideally organized to modulate widely distributed neural systems and to regulate the switch between internal attention and salient stimuli in the environment. The current randomized placebo (PLC)-controlled between-subject pharmacological resting-state fMRI study in N = 187 (OXT, n = 94; PLC, n = 93; single-dose intranasal administration) healthy male and female participants employed an independent component analysis approach to determine the modulatory effects of OXT on the within- and between-network dynamics of the DAN-SN-DN triple network system. OXT increased the functional integration between subsystems within SN and DN and increased functional segregation of the DN with both attentional control networks (SN and DAN). Whereas no sex differences were observed, OXT effects on the DN-SN interaction were modulated by autistic traits. Together, the findings suggest that OXT may facilitate efficient attention allocation by modulating the intrinsic functional dynamics between DN components and large-scale networks involved in external attentional demands (SN and DAN).


Assuntos
Atenção/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Vias Neurais/efeitos dos fármacos , Ocitócicos/farmacologia , Ocitocina/farmacologia , Administração Intranasal , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
6.
Int J Mol Sci ; 23(18)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36142428

RESUMO

Salt stress is a major abiotic stress factor affecting crop production, and understanding of the response mechanisms of seed germination to salt stress can help to improve crop tolerance and yield. The differences in regulatory pathways during germination in different salt-tolerant barley seeds are not clear. Therefore, this study investigated the responses of different salt-tolerant barley seeds during germination to salt stress at the proteomic and metabolic levels. To do so, the proteomics and metabolomics of two barley seeds with different salt tolerances were comprehensively examined. Through comparative proteomic analysis, 778 differentially expressed proteins were identified, of which 335 were upregulated and 443 were downregulated. These proteins, were mainly involved in signal transduction, propanoate metabolism, phenylpropanoid biosynthesis, plant hormones and cell wall stress. In addition, a total of 187 salt-regulated metabolites were identified in this research, which were mainly related to ABC transporters, amino acid metabolism, carbohydrate metabolism and lipid metabolism; 72 were increased and 112 were decreased. Compared with salt-sensitive materials, salt-tolerant materials responded more positively to salt stress at the protein and metabolic levels. Taken together, these results suggest that salt-tolerant germplasm may enhance resilience by repairing intracellular structures, promoting lipid metabolism and increasing osmotic metabolites. These data not only provide new ideas for how seeds respond to salt stress but also provide new directions for studying the molecular mechanisms and the metabolic homeostasis of seeds in the early stages of germination under abiotic stresses.


Assuntos
Germinação , Hordeum , Sistemas de Transporte de Aminoácidos/metabolismo , Hordeum/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Propionatos/metabolismo , Proteômica/métodos , Estresse Salino , Sementes/metabolismo , Estresse Fisiológico
7.
Int J Mol Sci ; 23(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36361814

RESUMO

Cuticular waxes comprise the hydrophobic layer that protects crops against nonstomatal water loss and biotic and abiotic stresses. Expanding on our current knowledge of the genes that are involved in cuticular wax biosynthesis and regulation plays an important role in dissecting the processes of cuticular wax metabolism. In this study, we identified the Cer-GN1 barley (Hordeum vulgare L.) mutant that is generated by ethyl methanesulfonate mutagenesis with a glossy spike phenotype that is controlled by a single recessive nuclear gene. A physiological analysis showed that the total cuticular wax loads of Cer-GN1 were one-third that of the progenitor wild-type (WT), and its water loss rate was significantly accelerated (p < 0.05). In addition, Cer-GN1 was defective in the glume's cuticle according to the toluidine blue dye test, and it was deficient in the tubule-shaped crystals which were observed on the glume surfaces by scanning electron microscopy. Using metabolomics and transcriptomics, we investigated the impacts of cuticular wax composition and waxy regulatory genes on the loss of the glaucous wax in the spikes of Cer-GN1. Among the differential metabolites, we found that 16-hydroxyhexadecanoic acid, which is one of the predominant C16 and C18 fatty acid-derived cutin monomers, was significantly downregulated in Cer-GN1 when it was compared to that of WT. We identified two novel genes that are located on chromosome 4H and are downregulated in Cer-GN1 (HvMSTRG.29184 and HvMSTRG.29185) that encode long-chain fatty acid omega-monooxygenase CYP704B1, which regulates the conversion of C16 palmitic acid to 16-hydroxyhexadecanoic acid. A quantitative real-time PCR revealed that the expression levels of HvMSTRG.29184 and HvMSTRG.29185 were downregulated at 1, 4, 8, 12, and 16 days after the heading stage in Cer-GN1 when it was compared to those of WT. These results suggested that HvMSTRG.29184 and HvMSTRG.29185 have CYP704B1 activity, which could regulate the conversion of C16 palmitic acid to 16-hydroxyhexadecanoic acid in barley. Their downregulation in Cer-GN1 reduced the synthesis of the cuticular wax components and ultimately caused the loss of the glaucous wax in the spikes. It is necessary to verify whether HvMSTRG.29184 and HvMSTRG.29185 truly encode a CYP704B1 that regulates the conversion of C16 palmitic acid to 16-hydroxyhexadecanoic acid in barley.


Assuntos
Hordeum , Hordeum/genética , Hordeum/metabolismo , Ácido Palmítico/metabolismo , Folhas de Planta/metabolismo , Ceras/metabolismo , Água/metabolismo , Regulação da Expressão Gênica de Plantas
8.
Entropy (Basel) ; 24(5)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35626467

RESUMO

The methods based on the convolutional neural network have demonstrated its powerful information integration ability in image fusion. However, most of the existing methods based on neural networks are only applied to a part of the fusion process. In this paper, an end-to-end multi-focus image fusion method based on a multi-scale generative adversarial network (MsGAN) is proposed that makes full use of image features by a combination of multi-scale decomposition with a convolutional neural network. Extensive qualitative and quantitative experiments on the synthetic and Lytro datasets demonstrated the effectiveness and superiority of the proposed MsGAN compared to the state-of-the-art multi-focus image fusion methods.

9.
Neuroimage ; 227: 117668, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33359350

RESUMO

The neuropeptide oxytocin is a key modulator of social-emotional behavior and its intranasal administration can influence the functional connectivity of brain networks involved in the control of attention, emotion and reward reported in humans. However, no studies have systematically investigated the effects of oxytocin on dynamic or directional aspects of functional connectivity. The present study employed a novel computational framework to investigate these latter aspects in 15 oxytocin-sensitive regions using data from randomized placebo-controlled between-subject resting state functional MRI studies incorporating 200 healthy subjects. In order to characterize the temporal dynamics, the 'temporal state' was defined as a temporal segment of the whole functional MRI signal which exhibited a similar functional interaction pattern among brain regions of interest. Results showed that while no significant effects of oxytocin were found on brain temporal state related characteristics (including temporal state switching frequency, probability of transitions between neighboring states, and averaged dwell time on each state) oxytocin extensively (n = 54 links) modulated effective connectivity among the 15 regions. The effects of oxytocin were primarily characterized by increased effective connectivity both between and within emotion, reward, salience, attention and social cognition processing networks and their interactions with the default mode network. Top-down control over emotional processing regions such as the amygdala was particularly affected. Oxytocin also increased effective homotopic interhemispheric connectivity in almost all these regions. Additionally, the effects of oxytocin on effective connectivity were sex-dependent, being more extensive in males. Overall, these findings suggest that modulatory effects of oxytocin on both within- and between-network interactions may underlie its functional influence on social-emotional behaviors, although in a sex-dependent manner. These findings may be of particular relevance to potential therapeutic use of oxytocin in psychiatric disorders associated with social dysfunction, such as autism spectrum disorder and schizophrenia, where directionality of treatment effects on causal interactions between networks may be of key importance .


Assuntos
Encéfalo/efeitos dos fármacos , Rede Nervosa/efeitos dos fármacos , Vias Neurais/efeitos dos fármacos , Ocitocina/farmacologia , Adulto , Mapeamento Encefálico/métodos , Método Duplo-Cego , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Adulto Jovem
10.
Pers Individ Dif ; 168: 110399, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32982001

RESUMO

The outbreak of coronavirus disease 2019 (COVID-19) and its worldwide spread have brought economic, social and personal stress. To better understand human adjustments to this public health emergency and its underlying mechanism, the relationship between perceived parental psychological control in emerging adults and individual's emotional reactivity to COVID-19 as well as the role of empathy was examined. The study was conducted among 445 emerging adults using questionnaires measuring parental psychological control, empathy, and emotional reactivities in the initial stage of COVID-19. Results revealed that parental psychological control conferred risks for individual's increased negative emotional reactivity to this pandemic. Moreover, our findings shedlight on personal distress as a mechanism through which parental psychological control induces negative emotional reactivities. Although no direct effect between parental psychological control and positive emotional reactivity was found, personal distress and perspective taking mediate the association in an opposite way. Findings have implications for predicting and intervening mental health problems in COVID-19 pandemic and future public health emergency.

11.
Bull Environ Contam Toxicol ; 106(3): 545-556, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33638675

RESUMO

Heavy metals pollution and salinization of soils are widely distributed in agricultural soils. This study investigated the effects of five heavy metals and five heavy metals-contaminated salt on seed germination and seedling growth of halophyte Halogeton glomeratus (H. glomeratus). The results showed that seed germination, fresh weight (FW), dry weight (DW), radicles relative viability and ion contents (Cu2+, Ni2+, Zn2+, Cd2+ and Pb2+) of H. glomeratus were affected by different heavy metals and heavy metal-polluted 100 mM NaCl treatments. Ion contents in plumules increased with the increase of heavy metal concentrations with or without NaCl addition. Moreover, the accumulation levels of metals in the concentrations of Cu2+, Zn2+ and Pb2+ supplying 100 mM NaCl were higher than that without NaCl treatment. This can provide new insights into the value of H. glomeratus for phytoremediation of soil affected by heavy metals and also in combination with salinity.


Assuntos
Chenopodiaceae , Metais Pesados , Poluentes do Solo , Germinação , Metais Pesados/análise , Metais Pesados/toxicidade , Plantas Tolerantes a Sal , Plântula/química , Sementes/química , Cloreto de Sódio , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
12.
Entropy (Basel) ; 23(4)2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33808436

RESUMO

The unavoidable noise often present in synthetic aperture radar (SAR) images, such as speckle noise, negatively impacts the subsequent processing of SAR images. Further, it is not easy to find an appropriate application for SAR images, given that the human visual system is sensitive to color and SAR images are gray. As a result, a noisy SAR image fusion method based on nonlocal matching and generative adversarial networks is presented in this paper. A nonlocal matching method is applied to processing source images into similar block groups in the pre-processing step. Then, adversarial networks are employed to generate a final noise-free fused SAR image block, where the generator aims to generate a noise-free SAR image block with color information, and the discriminator tries to increase the spatial resolution of the generated image block. This step ensures that the fused image block contains high resolution and color information at the same time. Finally, a fused image can be obtained by aggregating all the image blocks. By extensive comparative experiments on the SEN1-2 datasets and source images, it can be found that the proposed method not only has better fusion results but is also robust to image noise, indicating the superiority of the proposed noisy SAR image fusion method over the state-of-the-art methods.

13.
Plant Dis ; 104(2): 320-322, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31804900

RESUMO

Pyrenophora graminea is the causative agent of barley leaf stripe disease. In this study, the strong pathogenic isolate QWC was used to generate DNA for Illumina sequencing. After assembly, its genome size was 42.5 Mb, consisting of 264 scaffolds, and a total of 10,376 genes was predicted. This is the first genome resource available for P. graminea. The genome sequences of P. graminea will accelerate the understanding interaction of P. graminea and barley.


Assuntos
Ascomicetos , Hordeum , Doenças das Plantas , Folhas de Planta
14.
Plant Dis ; 104(6): 1574-1577, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32293998

RESUMO

Spot blotch, caused by fungal pathogen Bipolaris sorokiniana Shoemaker, is one of the most frequent diseases affecting barley-growing regions worldwide. In this study, we reported the genome sequence of the highly virulent B. sorokiniana strain GN1 using the Illumina HiSeq 4000 platform. In total, 57 million 150-nucleotide paired-end clean reads were obtained and assembled into 96 scaffolds with an estimated genome size of 34.33 Mb. Furthermore, we identified genes that may be associated with strain-specific virulence and performed phylogenetic analysis of GN1 with five other Bipolaris spp. These results for GN1 will provide important information in understanding its molecular underpinning of pathogenicity and help identify novel sources of genetic resistance for improving disease resistance in barley.


Assuntos
Ascomicetos , Hordeum , Resistência à Doença , Humanos , Filogenia , Doenças das Plantas
15.
Neuroimage ; 184: 781-789, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30266264

RESUMO

Interactions between oxytocin and the basal ganglia are central in current overarching conceptualizations of its broad modulatory effects on behavior. Whereas evidence from animal models emphasizes the critical role of the ventral striatum in the behavioral effects of oxytocin, region-specific contributions of the basal ganglia have not been systematically explored in humans. The present study combined the randomized placebo-controlled administration of oxytocin versus placebo in healthy men (n = 144) with fMRI-based resting-state functional connectivity to determine the modulatory role of oxytocin on the major basal ganglia pathways. Oxytocin specifically increased connectivity between ventral striatal and pallidal nodes with upstream frontal regions, whereas it decreased the strengths of downstream pathways between the dorsal striatum and posterior cerebellum. These pathways have previously been implicated in salience, reward and behavioral flexibility, thus shaping goal-directed behavior. Given the importance of aberrant striatal intrinsic organization in autism, addiction and schizophrenia the present findings may suggest new mechanistic perspectives for the therapeutic potential of oxytocin in these disorders.


Assuntos
Cerebelo/fisiologia , Corpo Estriado/fisiologia , Lobo Frontal/fisiologia , Ocitocina/fisiologia , Adulto , Mapeamento Encefálico , Cerebelo/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Lobo Frontal/efeitos dos fármacos , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiologia , Ocitocina/administração & dosagem , Estriado Ventral/fisiologia , Adulto Jovem
16.
Neuroimage ; 183: 62-72, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30086408

RESUMO

We interact socially and form bonds with others because such experiences are rewarding. However, an insecure attachment style or social anxiety can reduce these rewarding effects. The neuropeptide oxytocin (OXT) may facilitate social interactions either by increasing their rewarding experience or by attenuating anxiety, although effects can be sex- and attachment-style dependent. In this study, 128 pairs of same-sex friends completed a social sharing paradigm in a double-blind, placebo-controlled, between-subject design with one friend inside an MRI scanner and the other in a remote behavioral testing room. In this way we could examine whether intranasal-OXT differentially modulated the emotional impact of social sharing and associated neural processing. Additionally, we investigated if OXT effects were modulated by sex and attachment style. Results showed that in women, but not men, OXT increased ratings for sharing stimuli with their friend but not with a stranger, particularly in the friend in the scanner. Corresponding neuroimaging results showed that OXT decreased both amygdala and insula activity as well as their functional connectivity in women when they shared with friends but had the opposite effect in men. On the other hand, OXT did not enhance responses in brain reward circuitry. In the PLC treated group amygdala responses in women when they shared pictures with their friend were positively associated with attachment anxiety and OXT uncoupled this. Our findings demonstrate that OXT facilitates the impact of sharing positive experiences with others in women, but not men, and that this is associated with differential effects on the amygdala and insula and their functional connections. Furthermore, OXT particularly reduced increased amygdala responses during sharing in individuals with higher attachment anxiety. Thus, OXT effects in this context may be due more to reduced anxiety when sharing with a friend than to enhanced social reward.


Assuntos
Tonsila do Cerebelo , Córtex Cerebral , Neuroimagem Funcional/métodos , Relações Interpessoais , Neuropeptídeos/farmacologia , Apego ao Objeto , Ocitocina/farmacologia , Recompensa , Facilitação Social , Adolescente , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/fisiologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/fisiologia , Feminino , Amigos , Humanos , Imageamento por Ressonância Magnética , Masculino , Neuropeptídeos/administração & dosagem , Ocitocina/administração & dosagem , Reconhecimento Visual de Modelos/fisiologia , Fatores Sexuais , Adulto Jovem
17.
Int J Neuropsychopharmacol ; 21(10): 918-925, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30085122

RESUMO

Background: The neuropeptide oxytocin can extensively modulate human social behavior and affective processing, and its effects can be interpreted in terms of mediating approach-avoidance motivational processes. However, little is known about how oxytocin mediates approach-avoidance behavior and particularly the underlying neural mechanisms. Methods: In a randomized, double-blind, between-subject design, the present pharmaco-fMRI study used an approach-avoidance paradigm to investigate oxytocin's effects on approach-avoidance behavior and associated neural mechanisms. Results: Results revealed that oxytocin generally decreased activity in the right striatum irrespective of response (approach/avoidance) and social context, suggesting an inhibitory effect on motivational representation during both appetitive approach and aversive avoidance. Importantly, while on the behavioral level oxytocin selectively enhanced accuracy when approaching social positive stimuli, on the neural level it decreased left ventral and right dorsal anterior insula activity in response to social vs nonsocial positive stimuli compared with the placebo treatment. The left ventral anterior insula activity was negatively correlated with the corresponding accuracy difference scores in the oxytocin but not in the placebo group. Conclusion: Given the role of the ventral anterior insula in emotional processing and the dorsal anterior insula in salience processing, the oxytocin-induced suppression of activity in these regions may indicate that oxytocin is acting to reduce interference from hyper-activity in core regions of the emotional and salience networks when approaching salient positive social stimuli and thereby to promote social interaction. Thus, oxytocin may be of potential therapeutic benefit for psychiatric disorders exhibiting avoidance of social stimuli.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Comportamento de Escolha/efeitos dos fármacos , Ocitocina/farmacologia , Comportamento Social , Administração Intranasal , Corpo Estriado/efeitos dos fármacos , Método Duplo-Cego , Neuroimagem Funcional , Voluntários Saudáveis , Humanos , Imageamento por Ressonância Magnética , Masculino , Neuropeptídeos/farmacologia , Ocitocina/administração & dosagem , Adulto Jovem
18.
Sensors (Basel) ; 18(10)2018 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-30322174

RESUMO

In this paper, we propose a boosting synthetic aperture radar (SAR) image despeckling method based on non-local weighted group low-rank representation (WGLRR). The spatial structure information of SAR images leads to the similarity of the patches. Furthermore, the data matrix grouped by the similar patches within the noise-free SAR image is often low-rank. Based on this, we use low-rank representation (LRR) to recover the noise-free group data matrix. To maintain the fidelity of the recovered image, we integrate the corrupted probability of each pixel into the group LRR model as a weight to constrain the fidelity of recovered noise-free patches. Each single patch might belong to several groups, so different estimations of each patch are aggregated with a weighted averaging procedure. The residual image contains signal leftovers due to the imperfect denoising, so we strengthen the signal by leveraging on the availability of the denoised image to suppress noise further. Experimental results on simulated and actual SAR images show the superior performance of the proposed method in terms of objective indicators and of perceived image quality.

19.
Neuroimage ; 162: 127-137, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28877512

RESUMO

In line with animal models indicating sexually dimorphic effects of oxytocin (OXT) on social-emotional processing, a growing number of OXT-administration studies in humans have also reported sex-dependent effects during social information processing. To explore whether sex-dependent effects already occur during early, subliminal, processing stages the present pharmacological fMRI-study combined the intranasal-application of either OXT or placebo (n = 86-43 males) with a backward-masking emotional face paradigm. Results showed that while OXT suppressed inferior frontal gyrus, dorsal anterior cingulate and anterior insula responses to threatening face stimuli in men it increased them in women. In women increased anterior cingulate reactivity during subliminal threat processing was also positively associated with trait anxiety. On the network level, sex-dependent effects were observed on amygdala, anterior cingulate and inferior frontal gyrus functional connectivity that were mainly driven by reduced coupling in women following OXT. Our findings demonstrate that OXT produces sex-dependent effects even at the early stages of social-emotional processing, and suggest that while it attenuates neural responses to threatening social stimuli in men it increases them in women. Thus in a therapeutic context OXT may potentially produce different effects on anxiety disorders in men and women.


Assuntos
Emoções/efeitos dos fármacos , Ocitocina/farmacologia , Caracteres Sexuais , Percepção Visual/efeitos dos fármacos , Adolescente , Adulto , Método Duplo-Cego , Emoções/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
20.
Inorg Chem ; 56(18): 11087-11095, 2017 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-28841298

RESUMO

On the basis of a rough rule of thumb that the difference in ionic radius for the interstitial cationic pair may affect the structure of some nitride and carbonitride compounds, a novel carbonitride phosphor, YScSi4N6C:Ce3+, was successfully designed. The crystal structure (space group P63mc (No. 186), a = b = 5.9109(8) Å, c = 9.67701(9) Å, α = ß = 90°, γ = 120°) was characterized by single-crystal synchrotron X-ray diffraction and further confirmed by powder X-ray diffraction and refined with Rietveld methods. Ce3+-doped YScSi4N6C shows a broad excitation band ranging from 280 to 425 nm and a broad cyan emission band peaking at about 469 nm upon excitation by near-UV light (400 nm). The mechanism of thermal quenching for this phosphor was also investigated. In addition, a white light-emitting diode (w-LED) was prepared by coating a near-UV chip (λem = 405 nm) with YScSi4N6C:Ce3+, ß-sialon:Eu2+ (green), and CaAlSiN3:Eu2+ (red) phosphors. It emitted a well-distributed warm white light with high color rendering index (CRI) of 94.7 and a correlated color temperature (CCT) of 4159 K. The special color rendering index R12 of the obtained white light was as high as 88. All of the results indicate that this novel phosphor can compensate for the cyan cavity and has potential applications in the full-spectrum lighting field.

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