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1.
Nutrients ; 16(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38732499

RESUMO

Individuals exhibiting high scores on the fatness subscale of the negative-physical-self scale (NPSS-F) are characterized by heightened preoccupation with body fat accompanied by negative body image perceptions, often leading to excessive dieting behaviors. This demographic constitutes a considerable segment of the populace in China, even among those who are not obese. Nonetheless, scant empirical inquiries have delved into the behavioral and neurophysiological profiles of individuals possessing a healthy body mass index (BMI) alongside elevated NPSS-F scores. This study employed an experimental paradigm integrating go/no-go and one-back tasks to assess inhibitory control and working memory capacities concerning food-related stimuli across three adult cohorts: those with normal weight and low NPSS-F scores, those with normal weight and high NPSS-F scores, and individuals classified as obese. Experimental stimuli comprised high- and low-caloric-food pictures with concurrent electroencephalogram (EEG) and photoplethysmogram (PPG) recordings. Individuals characterized by high NPSS-F scores and normal weight exhibited distinctive electrophysiological responses compared to the other two cohorts, evident in event-related potential (ERP) components, theta and alpha band oscillations, and heart rate variability (HRV) patterns. In essence, the findings underscore alterations in electrophysiological reactivity among individuals possessing high NPSS-F scores and a healthy BMI in the context of food-related stimuli, underscoring the necessity for increased attention to this demographic alongside individuals affected by obesity.


Assuntos
Índice de Massa Corporal , Obesidade , Humanos , Masculino , Feminino , Obesidade/fisiopatologia , Obesidade/psicologia , Adulto , Adulto Jovem , Eletroencefalografia , Potenciais Evocados , Memória de Curto Prazo/fisiologia , Frequência Cardíaca/fisiologia , Inibição Psicológica , China , Imagem Corporal/psicologia
2.
Cogn Neurodyn ; 15(6): 1015-1022, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34790268

RESUMO

It is well known that different names of color can lead to distinct attractions to people. To study the neural mechanism underlying this phenomenon, an implicit association test task was designed for color names, in which participants were required to select the possible meanings of a Greek phrase from two color names (in Chinese). The behavioral results showed that the participants were more likely to select novel names for long Greek phrases and dates names for short Greek phrases. The EEG results showed that the mean amplitude of N1 was greater for selections of novel color names than selections of dates names for Greek phrases. Meanwhile, the mean amplitude of N3 for novel color names was more negative than that of dates color names. Significant interaction effect of N3 was also found for the four kinds of selections between Greek phrases and Chinese color names. Moreover, a frontal-positive and occipital-negative distribution for scalp topography of N1 was found, while the scalp topography of N3 was opposite as frontal-negative and occipital-positive distribution, suggesting the importance of visual cortex for perception of the color names and prefrontal cortex for integration and decision of selection. In summary, the results here indicated that colors with novel names could easily attract people's attention than colors with dates names, which might shed light on the usage of color names in real life.

3.
Neural Plast ; 2021: 6692411, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33531892

RESUMO

Postinhibitory facilitation (PIF) of neural firing presents a paradoxical phenomenon that the inhibitory effect induces enhancement instead of reduction of the firing activity, which plays important roles in sound location of the auditory nervous system, awaited theoretical explanations. In the present paper, excitability and threshold mechanism for the PIF phenomenon is presented in the Morris-Lecar model with type I, II, and III excitabilities. Firstly, compared with the purely excitatory stimulations applied to the steady state, the inhibitory preceding excitatory stimulation to form pairs induces the firing rate increased for type II and III excitabilities instead of type I excitability, when the interval between the inhibitory and excitatory stimulation within each pair is suitable. Secondly, the threshold mechanism for the PIF phenomenon is acquired. For type II and III excitabilities, the inhibitory stimulation induces subthreshold oscillations around the steady state. During the middle and ending phase of the ascending part and the beginning phase of the descending part within a period of the subthreshold oscillations, the threshold to evoke an action potential by an excitatory stimulation becomes weaker, which is the cause for the PIF phenomenon. Last, a theoretical estimation for the range of the interval between the inhibitory and excitatory stimulation for the PIF phenomenon is acquired, which approximates half of the intrinsic period of the subthreshold oscillations for the relatively strong stimulations and becomes narrower for the relatively weak stimulations. The interval for the PIF phenomenon is much shorter for type III excitability, which is closer to the experiment observation, due to the shorter period of the subthreshold oscillations. The results present the excitability and threshold mechanism for the PIF phenomenon, which provide comprehensive and deep explanations to the PIF phenomenon.


Assuntos
Potenciais de Ação/fisiologia , Modelos Neurológicos , Inibição Neural/fisiologia , Neurônios/fisiologia , Limiar Diferencial/fisiologia , Humanos
4.
Bioresour Technol ; 298: 122576, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31851897

RESUMO

Biochar from pyrolysis/gasification is relatively poor in oxygen-containing groups and low in micro/mesoporosity, which constrains its adsorption performance. Here, thermal air treatment (TAT) at a mild condition (300 °C in air) was applied to oxygenate the surfaces of various biochars and modify their pore structures for the promotion of their uranium (U(VI)) adsorptions. Results showed that TAT had a high product yield (>76%), increased the O contents, O/C ratios and O-containing groups in biochars, and substantially developed the micro/mesoporosities of biochars. Batch adsorption results showed that TAT remarkably improved U(VI) adsorption capacities of various biochars. Specifically, the maximum U(VI) adsorption capacities of ash-poor corn cob biochar and ash-rich sewage sludge biochar were increased by 137% to 163 mg/g and 23% to 97 mg/g, respectively. Thus, TAT might be a promising strategy to engineer various biochars for adsorptive applications.


Assuntos
Urânio , Adsorção , Carvão Vegetal , Esgotos
5.
Bioresour Technol ; 294: 122142, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31561155

RESUMO

Compared to pyrochar (PC), little is known about the capability of torrefaction char (TC) in water pollution control. In this study, the physicochemical properties of TC and PC, and their adsorption performances for uranium (U(VI)) and methylene blue (MB) were investigated. Results showed that TC was higher in oxygen content, and richer in oxygen-containing functional groups. The maximum U(VI) and MB adsorption capacities were increased from 56.21 and 192.67 mg/g for PC, respectively, to >100 and >350 mg/g for TC, respectively, indicating that TC was much more efficient than PC. Furthermore, torrefaction atmosphere affected the adsorption performance of resulting TC. For example, TC from N2 was more efficient in MB adsorption, while TC from air was more efficient in U(VI) adsorption. Thus, attributed to the lower processing temperature, simpler preparation route, and higher adsorption capacity, TC could be a competent candidate for water pollution control.


Assuntos
Oxigênio , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Cinética , Poluição da Água
6.
PLoS One ; 10(8): e0135374, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26273833

RESUMO

Periostin (PN, gene name POSTN) is an extracellular matrix protein that is up-regulated in bronchial epithelial cells and lung fibroblasts by TH-2 cytokines. Its paralog, TGF-ß-induced protein (ßig-h3, gene name TGFBI), is also expressed in the lung and up-regulated in bronchial myofibroblasts by TGF-ß. PN and ßig-h3 contain fasciclin 1 modules that harbor putative recognition sequences for γ-glutamyl carboxylase and are annotated in UniProt as undergoing vitamin K-dependent γ-carboxylation of multiple glutamic acid residues. γ-carboxylation profoundly alters activities of other proteins subject to the modification, e.g., blood coagulation factors, and would be expected to alter the structure and function of PN and ßig-h3. To analyze for the presence of γ-carboxylation, proteins extracted from fibrotic lung were reacted with monoclonal antibodies specific for PN, ßig-h3, or modification with γ-carboxyglutamic acid (Gla). In Western blots of 1-dimensional gels, bands stained with anti-PN or -ßig-h3 did not match those stained with anti-Gla. In 2-dimensional gels, anti-PN-positive spots had pIs of 7.0 to >8, as expected for the unmodified protein, and there was no overlap between anti-PN-positive and anti-Gla-positive spots. Recombinant PN and blood coagulation factor VII were produced in HEK293 cells that had been transfected with vitamin K 2, 3-epoxide reductase C1 to optimize γ-carboxylation. Recombinant PN secreted from these cells did not react with anti-Gla antibody and had pIs similar to that found in extracts of fibrotic lung whereas secreted factor VII reacted strongly with anti-Gla antibody. Over 67% coverage of recombinant PN was achieved by mass spectrometry, including peptides with 19 of the 24 glutamates considered targets of γ-carboxylation, but analysis revealed no modification. Over 86% sequence coverage and three modified glutamic acid residues were identified in recombinant fVII. These data indicate that PN and ßig-h3 are not subject to vitamin K-dependent γ-carboxylation.


Assuntos
Moléculas de Adesão Celular/metabolismo , Pulmão/metabolismo , Processamento de Proteína Pós-Traducional , Fibrose Pulmonar/metabolismo , Vitamina K/metabolismo , Moléculas de Adesão Celular/genética , Feminino , Células HEK293 , Humanos , Pulmão/patologia , Masculino , Engenharia Metabólica , Fibrose Pulmonar/genética , Fibrose Pulmonar/patologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
7.
PLoS One ; 10(4): e0124941, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25919138

RESUMO

Intrinsically disordered sequences within bacterial adhesins bind to E-strands in the ß-sheets of multiple FNI modules of fibronectin (FN) by anti-parallel ß-strand addition, also called tandem ß-zipper formation. The FUD segment of SfbI of Streptococcus pyogenes and Bbk32 segment of BBK32 of Borrelia burgdorferi, despite being imbedded in different adhesins from different bacteria, target the same 2-5,8-9 FNI modules, 2-5,8-9 FNI, in the N-terminal 70-kDa region (FN70K) of FN. To facilitate further comparisons, FUD, Bbk32, two other polypeptides based on SfbI that target 1-5 FNI (HADD) and 2-5 FNI (FRD), and mutant Bbk32 (ΔBbk32) were produced with fluorochromes placed just outside of the binding sequences. Unlabeled FUD competed ~ 1000-fold better for binding of labeled Bbk32 to FN than unlabeled Bbk32 competed for binding of labeled FUD to FN. Binding kinetics were determined by fluorescence polarization in a stopped-flow apparatus. On-rates for FUD, Bbk32, HADD, and FRD were similar, and all bound more rapidly to FN70K fragment than to full length FN. In stopped-flow displacement and size exclusion chromatographic assays, however, k off for FUD or HADD to FN70K or FN was considerably lower compared to k off of FRD or Bbk32. FUD and Bbk32 differ in the spacing between sequences that interact with 3FNI and 4FNI or with 5FNI and 8FNI. ΔBbk32, in which 2 residues were removed from Bbk32 to make the spacing more like FUD, had a k off intermediate between that of Bbk32 and FUD. These results indicate a "folding-after-binding" process after initial association of certain polypeptide sequences to FN that results in formation of a stable complex and is a function of number of FNI modules engaged by the polypeptide, spacing of engagement sites, and perhaps flexibility within the polypeptide-FN complex. We suggest that contributions of SfbI and BBK32 adhesins to bacterial pathogenicity may be determined in part by stability of adhesin-FN complexes.


Assuntos
Fibronectinas/química , Fibronectinas/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Ligação Competitiva , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Fluorometria , Cinética , Ligantes , Dados de Sequência Molecular , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Peptídeos/química , Peptídeos/metabolismo , Ligação Proteica , Estabilidade Proteica , Estrutura Secundária de Proteína , Solubilidade
8.
J Biol Chem ; 290(8): 4866-4876, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25525266

RESUMO

SFS is a non-anchored protein of Streptococcus equi subspecies equi that causes upper respiratory infection in horses. SFS has been shown to bind to fibronectin (FN) and block interaction of FN with type I collagen. We have characterized interactions of a recombinant 60-mer polypeptide, R1R2, with FN. R1R2 contains two copies of collagen-like 19-residue repeats. Experiments utilizing various FN fragments and epitope-mapped anti-FN monoclonal antibodies located the binding site to (8-9)FNI modules of the gelatin-binding domain. Fluorescence polarization and competitive enzyme-linked assays demonstrated that R1R2 binds preferentially to compact dimeric FN rather than monomeric constructs containing (8-9)FNI or a large dimeric FN construct that is constitutively in an extended conformation. In contrast to bacterial peptides that bind (2-5)FNI in addition to (8-9)FNI, R1R2 did not cause conformational extension of FN as assessed by a conformationally sensitive antibody. Equilibrium and stopped-flow binding assays and size exclusion chromatography were compatible with a two-step binding reaction in which each of the repeats of R1R2 interacts with one of the subunits of dimeric FN, resulting in a stable complex with a slow koff. In addition to not binding to type I collagen, the R1R2·FN complex incorporated less efficiently into extracellular matrix than free FN. Thus, R1R2 binds to FN utilizing features of compact soluble FN and in doing so interferes with the organization of the extracellular matrix. A similar bivalent binding strategy may underlie the collagen-FN interaction.


Assuntos
Proteínas de Bactérias/química , Fibronectinas/química , Streptococcus equi/química , Proteínas de Bactérias/genética , Fibronectinas/genética , Estrutura Terciária de Proteína , Streptococcus equi/genética
9.
Int J Environ Res Public Health ; 6(12): 3025-39, 2009 12.
Artigo em Inglês | MEDLINE | ID: mdl-20049243

RESUMO

The natural environment factor is one of the main indexes for evaluating human habitats, sustained economic growth and ecological health status. Based on Geographic Information System (GIS) technology and an analytic hierarchy process method, this article presents the construction of the Natural Environment Suitability Index (NESI) model of China by using natural environment data including climate, hydrology, surface configuration and ecological conditions. The NESI value is calculated in grids of 1 km by 1 km through ArcGIS. The spatial regularity of NESI is analyzed according to its spatial distribution and proportional structure. The relationship of NESI with population distribution and economic growth is also discussed by analyzing NESI results with population distribution data and GDP data in 1 km by 1 km grids. The study shows that: (1) the value of NESI is higher in the East and lower in the West in China; The best natural environment area is the Yangtze River Delta region and the worst are the northwest of Tibet and southwest of Xinjiang. (2) There is a close correlation among natural environment, population distribution and economic growth; the best natural environment area, the Yangtze River Delta region, is also the region with higher population density and richer economy. The worst natural environment areas, Northwest and Tibetan Plateau, are also regions with lower population density and poorer economies.


Assuntos
Conservação dos Recursos Naturais/estatística & dados numéricos , Crescimento Demográfico , China , Demografia , Sistemas de Informação Geográfica , Produto Interno Bruto/estatística & dados numéricos , Humanos , Modelos Estatísticos , Modelos Teóricos , Estatística como Assunto
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