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1.
Langmuir ; 40(24): 12709-12720, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38843518

RESUMO

Great aqueous dispersibility, a large specific surface area, and high impermeability make graphene oxide (GO) the ideal candidate for a high-performance corrosion inhibitor. Numerous symmetrical modification methods have been reported to enhance the adsorption of GO on metal surfaces in various corrosive media. This work aims to investigate the enhancement and mechanism of unilateral hydrophobic modification on the corrosion inhibition performance of GO. In this study, amphiphilic Janus GO (JGO) was prepared by grafting hydrophobic alkyl chains on one side of GO, and its anticorrosion performance was evaluated via weight loss experiments and electrochemical tests. The results revealed that the corrosion inhibition efficiency for Q235 mild steel (MS) in a 1 M HCl aqueous solution of 25 ppm JGO (81.08%) was much higher than that of GO at the same concentration (22.12%). Furthermore, the Langmuir adsorption isotherm and computational study demonstrated that the synergistic effect of physical adsorption and chemical adsorption promoted the hydrophilic side of JGO close to the surface of the metal, and the dense protective layer was formed by the hydrophobic chains toward the corrosive medium, which effectively hindered the corrosion of MS by the acidic liquid. This study emphasizes the significant role of asymmetrically modified hydrophobic alkyl chains in improving the corrosion prevention performance of GO and provides a perspective for the structural design of GO-based corrosion inhibitors.

2.
BMC Geriatr ; 23(1): 379, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37340377

RESUMO

BACKGROUND: This study aimed to evaluate whether the low appendicular skeletal muscle index (ASMI) is closely associated with the risk of carotid artery plaque (CAP) in postmenopausal women with and without hypertension/hyperglycemia stratified by body mass index (BMI) categories. METHODS: A total of 2048 Chinese postmenopausal women aged 40-88 years were eventually enrolled in this retrospective study. Skeletal muscle mass was estimated by using segmental multifrequency bioelectrical impedance analysis. ASMI was defined as follows: appendicular skeletal muscle mass(kg)/[height(m)]2. CAP was assessed by B-mode ultrasound. We explored the association between ASMI quartiles or low skeletal muscle mass and the risk of CAP by using multivariate-adjusted logistic regression models. A potential nonlinear relationship was also tested using restricted cubic spline regression. RESULTS: CAP was observed in 289/1074 (26.9%) normal-weight and 319/974 (32.8%) overweight/obese postmenopausal women. Individuals with CAP had significantly lower ASMI values than those without (P < 0.001). The ASMI value also showed a linear relationship with the CAP risk in postmenopausal women stratified by BMI category (Pfor non-linearity > 0.05). In comparison with the highest ASMI quartile, the lowest ASMI quartile was significantly associated with a high risk of CAP development in non-hypertensive individuals with normal weight (odds ratio [OR] = 2.43; 95% confidence interval [CI]: 1.44 ~ 4.12) or overweight/obesity (OR = 4.82, 95% CI: 2.79 ~ 8.33), hypertensive individuals with normal weight (OR = 5.90, 95% CI: 1.46 ~ 11.49) or overweight/obesity (OR = 7.63, 95% CI: 1.62 ~ 35.86), non-hyperglycemic individuals with normal weight (OR = 2.61, 95% CI: 1.54 ~ 4.43) or overweight/obesity (OR = 2.94, 95% CI: 1.84 ~ 4.70), and hyperglycemic individuals with normal weight (OR = 6.66, 95% CI: 1.08 ~ 41.10) or overweight/obesity (OR = 8.11, 95% CI: 2.69 ~ 24.49). Moreover, low skeletal muscle was independently associated with the risk of CAP in postmenopausal women, regardless of the BMI category. CONCLUSION: ASMI was inversely associated with the risk of CAP development in postmenopausal women, especially in patients with high blood sugar and/or hypertension, indicating that skeletal muscle mass maintenance may contribute to prevention of CAP in postmenopausal women.


Assuntos
Estenose das Carótidas , Hipertensão , Humanos , Feminino , Estudos Retrospectivos , Sobrepeso , Pós-Menopausa , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/epidemiologia , Músculo Esquelético/fisiologia , Obesidade/complicações , Obesidade/epidemiologia , Índice de Massa Corporal , Hipertensão/complicações , Hipertensão/epidemiologia
3.
Anesthesiology ; 136(4): 551-566, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35226725

RESUMO

BACKGROUND: Postoperative pulmonary complications are common. Aging and respiratory disease provoke airway hyperresponsiveness, high-risk surgery induces diaphragmatic dysfunction, and general anesthesia contributes to atelectasis and peripheral airway injury. This study therefore tested the hypothesis that inhalation of penehyclidine, a long-acting muscarinic antagonist, reduces the incidence of pulmonary complications in high-risk patients over the initial 30 postoperative days. METHODS: This single-center double-blind trial enrolled 864 patients age over 50 yr who were scheduled for major upper-abdominal or noncardiac thoracic surgery lasting 2 h or more and who had an Assess Respiratory Risk in Surgical Patients in Catalonia score of 45 or higher. The patients were randomly assigned to placebo or prophylactic penehyclidine inhalation from the night before surgery through postoperative day 2 at 12-h intervals. The primary outcome was the incidence of a composite of pulmonary complications within 30 postoperative days, including respiratory infection, respiratory failure, pleural effusion, atelectasis, pneumothorax, bronchospasm, and aspiration pneumonitis. RESULTS: A total of 826 patients (mean age, 64 yr; 63% male) were included in the intention-to-treat analysis. A composite of pulmonary complications was less common in patients assigned to penehyclidine (18.9% [79 of 417]) than those receiving the placebo (26.4% [108 of 409]; relative risk, 0.72; 95% CI, 0.56 to 0.93; P = 0.010; number needed to treat, 13). Bronchospasm was less common in penehyclidine than placebo patients: 1.4% (6 of 417) versus 4.4% (18 of 409; relative risk, 0.327; 95% CI, 0.131 to 0.82; P = 0.011). None of the other individual pulmonary complications differed significantly. Peak airway pressures greater than 40 cm H2O were also less common in patients given penehyclidine: 1.9% (8 of 432) versus 4.9% (21 of 432; relative risk, 0.381; 95% CI, 0.171 to 0.85; P = 0.014). The incidence of other adverse events, including dry mouth and delirium, that were potentially related to penehyclidine inhalation did not differ between the groups. CONCLUSIONS: In high-risk patients having major upper-abdominal or noncardiac thoracic surgery, prophylactic penehyclidine inhalation reduced the incidence of pulmonary complications without provoking complications.


Assuntos
Espasmo Brônquico , Atelectasia Pulmonar , Espasmo Brônquico/induzido quimicamente , Espasmo Brônquico/complicações , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Atelectasia Pulmonar/complicações , Quinuclidinas/efeitos adversos , Quinuclidinas/uso terapêutico
4.
BMC Plant Biol ; 21(1): 478, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34670494

RESUMO

BACKGROUND: Catechins are crucial in determining the flavour and health benefits of tea, but it remains unclear that how the light intensity regulates catechins biosynthesis. Therefore, we cultivated tea plants in a phytotron to elucidate the response mechanism of catechins biosynthesis to light intensity changes. RESULTS: In the 250 µmol·m- 2·s- 1 treatment, the contents of epigallocatechin, epigallocatechin gallate and total catechins were increased by 98.94, 14.5 and 13.0% respectively, compared with those in the 550 µmol·m- 2·s- 1 treatment. Meanwhile, the photosynthetic capacity was enhanced in the 250 µmol·m- 2·s- 1 treatment, including the electron transport rate, net photosynthetic rate, transpiration rate and expression of related genes (such as CspsbA, CspsbB, CspsbC, CspsbD, CsPsbR and CsGLK1). In contrast, the extremely low or high light intensity decreased the catechins accumulation and photosynthetic capacity of the tea plants. The comprehensive analysis revealed that the response of catechins biosynthesis to the light intensity was mediated by the photosynthetic capacity of the tea plants. Appropriately high light upregulated the expression of genes related to photosynthetic capacity to improve the net photosynthetic rate (Pn), transpiration rate (Tr), and electron transfer rate (ETR), which enhanced the contents of substrates for non-esterified catechins biosynthesis (such as EGC). Meanwhile, these photosynthetic capacity-related genes and gallic acid (GA) biosynthesis-related genes (CsaroB, CsaroDE1, CsaroDE2 and CsaroDE3) co-regulated the response of GA accumulation to light intensity. Eventually, the epigallocatechin gallate content was enhanced by the increased contents of its precursors (EGC and GA) and the upregulation of the CsSCPL gene. CONCLUSIONS: In this study, the catechin content and photosynthetic capacity of tea plants increased under appropriately high light intensities (250 µmol·m- 2·s- 1 and 350 µmol·m- 2·s- 1) but decreased under extremely low or high light intensities (150 µmol·m- 2·s- 1 or 550 µmol·m- 2·s- 1). We found that the control of catechin accumulation by light intensity in tea plants is mediated by the plant photosynthetic capacity. The research provided useful information for improving catechins content and its light-intensity regulation mechanism in tea plant.


Assuntos
Camellia sinensis/efeitos da radiação , Catequina/análogos & derivados , Catequina/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Fotossíntese/efeitos da radiação , Proteínas de Plantas/metabolismo , Camellia sinensis/genética , Camellia sinensis/fisiologia , Catequina/efeitos da radiação , Luz , Proteínas de Plantas/genética , Plântula/genética , Plântula/fisiologia , Plântula/efeitos da radiação , Regulação para Cima
5.
Molecules ; 25(18)2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32947902

RESUMO

The NaOH-HCl- and ethanol-pretreated pomelo peel samples were prepared to apply to the batch adsorption for epigallocatechin-3-gallate (EGCG). The characteristics of peel samples were determined by Fourier transform infrared spectroscopy, scanning electron microscopy and a laser particle analyzer. The results of the physiochemical properties of the peel samples demonstrate that these peel samples have a promising adsorption capacity for EGCG, because of the increased potential binding sites on the surface compared with those of untreated peel samples. These two peel samples showed enhanced adsorption capacities of EGCG compared with that of unmodified peel in terms of the isothermal adsorption process, which could be described by both Langmuir and Freundlich models, with the theoretical maximum adsorption capacity of 77.52 and 94.34 mg g-1 for the NaOH-HCl and ethanol-treated peel samples, respectively. The adsorption kinetics demonstrated an excellent fitness to pseudo-second-order, showing that chemisorption was the rate-limiting step. The thermodynamics analysis revealed that the adsorption reaction was a spontaneous and endothermic process. This work highlights that the processed pomelo peels have outstanding adsorption capacities for EGCG, which could be promising candidates for EGCG delivering in functional food application.


Assuntos
Catequina/análogos & derivados , Citrus/química , Adsorção , Catequina/química , Citrus/metabolismo , Frutas/química , Frutas/metabolismo , Cinética , Termodinâmica , Poluentes Químicos da Água/química
6.
J Proteome Res ; 18(1): 252-264, 2019 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-30427694

RESUMO

The quality of tea is highly related with the maturity of the fresh tea leaves at harvest. The present study investigated the proteomic and transcriptomic profiles of tea leaves with different maturity, using iTRAQ and RNA-seq technologies. A total of 4455 proteins and 27 930 unigenes were identified, with functional enrichment analyses of GO categorization and KEGG annotation. The compositions of flavonoids (catechins and flavonols) in tea leaves were determined. The total content of flavonoids decreased with leaf maturity, in accordance with the protein regulation patterns of shikimate, phenylpropanoid, and flavonoid pathways. The abundance of ANR had a positive correlation with epi-catechin content, while LAR abundance was positively related with catechin content ( P < 0.05). The biosynthetic network of flavonoid biosynthesis was discussed in combination with photosynthesis, primary metabolism, and transcription factors. Bud had the lowest activities of photosynthesis and carbon fixation but the highest flavonoid biosynthesis ability in opposite to mature leaf. SUS-INV switch might be an important joint for carbon flow shifting into the follow-up biochemical syntheses. This work provided a comprehensive overview on the functional protein profile changes of tea leaves at different growing stages and also proposed a research direction regarding the correlations between primary metabolism and flavonoid biosynthesis.


Assuntos
Camellia sinensis/química , Flavonoides/biossíntese , Perfilação da Expressão Gênica/métodos , Folhas de Planta/crescimento & desenvolvimento , Proteômica/métodos , Camellia sinensis/metabolismo , Catequina/metabolismo , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Folhas de Planta/química , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Chá/normas
7.
Int J Mol Sci ; 20(21)2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31694334

RESUMO

Hydrodynamic behaviors of bubble stream flow in fractal tree-shaped microchannels is investigated numerically based on a two-dimensional volume of fluid (VOF) method. Bubble breakup is examined in each level of bifurcation and the transition of breakup regimes is discussed in particular. The pressure variations at the center of different levels of bifurcations are analyzed in an effort to gain further insight into the underlying mechanism of bubble breakup affected by multi-levels of bifurcations in tree-shaped microchannel. The results indicate that due to the structure of the fractal tree-shaped microchannel, both lengths of bubbles and local capillary numbers decrease along the microchannel under a constant inlet capillary number. Hence the transition from the obstructed breakup and obstructed-tunnel combined breakup to coalescence breakup is observed when the bubbles are flowing into a higher level of bifurcations. Compared with the breakup of the bubbles in the higher level of bifurcations, the behaviors of bubbles show stronger periodicity in the lower level of bifurcations. Perturbations grow and magnify along the flow direction and the flow field becomes more chaotic at higher level of bifurcations. Besides, the feedback from the unequal downstream pressure to the upstream lower level of bifurcations affects the bubble breakup and enhances the upstream asymmetrical behaviors.


Assuntos
Fractais , Hidrodinâmica , Técnicas Analíticas Microfluídicas , Simulação por Computador , Desenho de Equipamento , Técnicas Analíticas Microfluídicas/instrumentação , Pressão
8.
Molecules ; 24(10)2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31108938

RESUMO

The distribution and diffusion behaviors of microscopic particles at fluorobenzene-water and pentanol-water interfaces are investigated using molecular dynamics simulation. The influences of Na+/Cl- ions and the steric effects of organic molecules are examined. The concentration distributions of different species, the orientations of oil molecules at the interface, and oil-water interface morphology as well as the diffusion behaviors of water molecules are explored and analyzed. The results indicate that a few fluorobenzene molecules move into the water phase influenced by Na+/Cl- ions, while the pentanol molecules at the interface prefer orientating their hydrophilic groups toward the water phase due to their large size. The water molecules more easily burst into the pentanol phase with larger molecular spaces. As the concentration of ions in the water phase increases, more water molecules enter into the pentanol molecules, leading to larger interface roughness and interface thickness. In addition, a lower diffusion coefficient for water molecules at the fluorobenzene-water interface are observed when introducing Na+/Cl- ions in the water phase, while for the pentanol-water system, the mobility of interfacial water molecules are enhanced with less ions and inhibited with more ions.


Assuntos
Fluorbenzenos/química , Pentanóis/química , Água/química , Cloretos/química , Difusão , Modelos Moleculares , Simulação de Dinâmica Molecular , Sódio/química
9.
J Sci Food Agric ; 98(11): 4135-4141, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29393516

RESUMO

BACKGROUND: Pomelo (Citrus grandis) is the largest citrus fruit, the peel of which is a well-known agricultural wastes. Disposal of pomelo peel after consumption is a serious environment problem. As a natural, versatile bio-absorbent, pomelo peel has shown excellent adsorption capacity for several pollutants, attributed to its micro-pores; however, there is no relevant report on its adsorption capacity for natural products or food ingredients. The ability of pomelo peel to adsorb epigallocatechin-3-gallate (EGCG) was examined in this study. The physicochemical characterizations of pomelo peel were determined by Fourier transform infrared spectroscopy, scanning electron microscopy and high-performance liquid chromatography. The adsorption process of EGCG onto pomelo peel from aqueous solution was carried out at a range of concentrations (50-800 mg L-1 ) and temperatures (25, 40 and 55 °C). RESULTS: The main components of pomelo peel are composed of dietary fiber, which provide sufficient adsorption sites during the adsorption process. The adsorption of EGCG onto pomelo peel showed excellent fitness with a pseudo-second-order model. Both Langmuir and Freundlich models were able to describe the isothermal adsorption of EGCG onto pomelo peel. The results of thermodynamic analysis suggested that adsorption is spontaneous and endothermic in nature, and that the process is likely to be dominated by a physisorption mechanism. CONCLUSION: The results of this study indicate that pomelo peel has potential adsorption capacity for EGCG, which can be used as an effective, low-cost carrier for delivery of natural products in functional food and dietary supplement applications. © 2018 Society of Chemical Industry.


Assuntos
Catequina/análogos & derivados , Citrus/química , Extratos Vegetais/química , Adsorção , Catequina/química , Portadores de Fármacos/química , Frutas/química , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier
10.
J Asian Nat Prod Res ; 17(3): 306-17, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25621771

RESUMO

Alzheimer's disease (AD) is the most common neurodegenerative disorder in which neuroinflammation plays an important role. FLZ is a novel synthetic derivative of natural squamosamide. Previous studies demonstrated that FLZ had neuroprotective effects on AD models and showed strong anti-inflammatory property in Parkinson's disease models. However, whether the neuroprotective effects of FLZ on AD are associated with its anti-inflammatory property is still not fully elucidated. In this study, we aimed to investigate the ability of FLZ in modulating inflammation. The results showed that FLZ significantly improved memory deficits and alleviated neuronal damage as well as neuronal loss in the hippocampus of mice intracerebroventricular injected with lipopolysaccharide (LPS). Mechanistic studies revealed that the neuroprotective effects of FLZ were due to the suppression of neuroinflammation induced by LPS, as indicated by inactivation of astrocytes and microglia, reduced production of tumor necrosis factor-α, interleukin-1ß, and nitric oxide, as well as decreased expression of cyclooxygenase-2 and inducible nitric oxide synthase. The beneficial effects of FLZ on AD were further supported by the finding that FLZ attenuated ß-amyloid production through inhibiting ß-amyloid precursor protein cleaving enzyme 1 expression. These results suggested that anti-inflammatory agent could be useful for the treatment of AD.


Assuntos
Benzenoacetamidas/farmacologia , Lipopolissacarídeos/farmacologia , Fenóis/farmacologia , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides , Animais , Benzenoacetamidas/química , Ciclo-Oxigenase 2 , Hipocampo/efeitos dos fármacos , Inflamação/tratamento farmacológico , Interleucina-1beta/metabolismo , Aprendizagem/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Microglia/efeitos dos fármacos , Estrutura Molecular , Fármacos Neuroprotetores/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fenóis/química , Fator de Necrose Tumoral alfa/metabolismo
11.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 36(3): 330-5, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24997829

RESUMO

Neuroinflammation in central nervous system, featured by glial cells activation, can always be found during the development of neurodegenerative diseases. Astrocytes, the most abundant glial cells in the brain, can release both pro-inflammatory and anti-inflammatory factors, thus playing a crucial role in the neuroinflammation. A variety of pattern-recognition receptors on astrocytes are involve d in the inflammatory response, particularly the scavenger receptor. Scavenger receptor is a cell surface glycoprotein and can identify diverse ligands. With a variety of biological functions, it may activate many signal pathways related to neuroinflammation, regulate the host defense and the development of neuroinflammation, and eventually regulate the process of neuroinflammation. Thus, it play a key role in the development of neurodegenerative diseases and many other conditions. This review summarizes the scavenger receptor expressed on astrocytes and how it regulates signal transduction pathways associated with neuroinflammation and thus participates in regulating neuroinflammation.


Assuntos
Astrócitos , Neurite (Inflamação) , Receptores Depuradores , Humanos
12.
Nurs Open ; 11(8): e70006, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39161133

RESUMO

AIM: To explore the correlations between examination tolerance and anxiety, knowledge needs and examination cooperation in sedation-free gastroscopy examinees. DESIGN: Cross-sectional survey using convenience sampling. METHODS: A total of 170 healthy adults who underwent sedation-free gastroenteroscopy were asked to complete a visual analogue scale (VAS) to rate their examination tolerance, the state anxiety questionnaire (S-AI), a newly designed knowledge needs questionnaire and a cooperation questionnaire. RESULTS: The VAS score was 4.47 ± 1.96, the state anxiety score was 39.46 ± 9.81, the total score for knowledge needs was 44.89 ± 11.02, and the average cooperation score was 2.47 ± 0.38. The VAS score during the examination positively correlated with the pretest state anxiety score and pretest knowledge needs score and negatively correlated with the examination cooperation score. The results of multiple linear regression analysis showed that after undergoing the examination for the first time, anxiety, body position and swallowing control were the main factors influencing the examination tolerance of sedation-free gastroscopy examinees. PATIENT OR PUBLIC CONTRIBUTION: We would like to thank the staff and patients of the participating hospital for their assistance and cooperation in performing the current study.


Assuntos
Ansiedade , Gastroscopia , Humanos , Feminino , Masculino , Estudos Transversais , Adulto , Ansiedade/psicologia , Estudos Prospectivos , Inquéritos e Questionários , Pessoa de Meia-Idade , Conhecimentos, Atitudes e Prática em Saúde
13.
PLoS One ; 19(8): e0308295, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39102395

RESUMO

Film cognition explores the influence of cinematic elements, such as editing and film color, on viewers' perception. The Kuleshov effect, a famous example of how editing influences viewers' emotional perception, was initially proposed to support montage theory through the Kuleshov experiment. This effect, which has since been recognized as a manifestation of point-of-view (POV) editing practices, posits that the emotional interpretation of neutral facial expressions is influenced by the accompanying emotional scene in a face-scene-face sequence. However, concerns persist regarding the validity of previous studies, often employing inauthentic film materials like static images, leaving the question of its existence in authentic films unanswered. This study addresses these concerns by utilizing authentic films in two experiments. In Experiment 1, multiple film clips were captured under the guidance of a professional film director and seamlessly integrated into authentic film sequences. 59 participants viewed these face-scene-face film sequences and were tasked with rating the valence and emotional intensity of neutral faces. The findings revealed that the accompanying fearful or happy scenes significantly influence the interpretation of emotion on neutral faces, eliciting perceptions of negative or positive emotions from the neutral face. These results affirm the existence of the Kuleshov effect within authentic films. In Experiment 2, 31 participants rated the valence and arousal of neutral faces while undergoing functional magnetic resonance imaging (fMRI). The behavioral results confirm the Kuleshov effect in the MRI scanner, while the neural data identify neural correlates that support its existence at the neural level. These correlates include the cuneus, precuneus, hippocampus, parahippocampal gyrus, post cingulate gyrus, orbitofrontal cortex, fusiform gyrus, and insula. These findings also underscore the contextual framing inherent in the Kuleshov effect. Overall, the study integrates film theory and cognitive neuroscience experiments, providing robust evidence supporting the existence of the Kuleshov effect through both subjective ratings and objective neuroimaging measurements. This research also contributes to a deeper understanding of the impact of film editing on viewers' emotional perception from the contemporary POV editing practices and neurocinematic perspective, advancing the knowledge of film cognition.


Assuntos
Emoções , Expressão Facial , Imageamento por Ressonância Magnética , Filmes Cinematográficos , Humanos , Emoções/fisiologia , Feminino , Masculino , Adulto , Adulto Jovem , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Estimulação Luminosa , Percepção Visual/fisiologia
14.
Food Res Int ; 194: 114939, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39232552

RESUMO

Understanding the epigenetic responses to mechanical wounding stress during the postharvest processing of oolong tea provides insight into the reprogramming of the tea genome and its impact on tea quality. Here, we characterized the 5mC DNA methylation and chromatin accessibility landscapes of tea leaves subjected to mechanical wounding stress during the postharvest processing of oolong tea. Analysis of the differentially methylated regions and preferentially accessible promoters revealed many overrepresented TF-binding motifs, highlighting sets of TFs that are likely important for the quality of oolong tea. Within these sets, we constructed a chromatin accessibility-mediated gene regulatory network specific to mechanical wounding stress. In combination with the results of the TF-centred yeast one-hybrid assay, we identified potential binding sites of CsMYC2 and constructed a gene regulatory network centred on CsMYC2, clarifying the potential regulatory role of CsMYC2 in the postharvest processing of oolong tea. Interestingly, highly accessible chromatin and hypomethylated cytosine were found to coexist in the promoter region of the indole biosynthesis gene (tryptophan synthase ß-subunit, CsTSB) under wounding stress, which indicates that these two important epigenetic regulatory mechanisms are jointly involved in regulating the synthesis of indole during the postharvest processing of oolong tea. These findings improve our understanding of the epigenetic regulatory mechanisms involved in quality formation during the postharvest processing of oolong tea.


Assuntos
Camellia sinensis , Metilação de DNA , Epigênese Genética , Regulação da Expressão Gênica de Plantas , Folhas de Planta , Folhas de Planta/genética , Camellia sinensis/genética , Regiões Promotoras Genéticas , Manipulação de Alimentos/métodos , Chá/genética , Estresse Mecânico , Genoma de Planta , Redes Reguladoras de Genes , Cromatina/metabolismo , Cromatina/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
15.
Food Res Int ; 181: 114136, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38448105

RESUMO

To achieve an integrative understanding of the spatial distribution and chronological flavoring compounds accumulation, desorption-electrospray-ionization coupled mass-spectrometry-imaging (DESI-MSI) and multi-omics techniques were performed on the leaf samples collected from the enzymatic-catalyzed-process (ECP) stage of Tieguanyin oolong tea manufacturing. The result of DESI-MSI visualization indicated transform or re-distribution of catechins, flavonols and amino acids were on-going attributing to the multi-stress over ECP stage. Out of identified 2621 non-volatiles and 45,771 transcripts, 43 non-volatiles and 12 co-expressed pathways were screened out as biomarkers and key cascades in response to adverse conditions. The targeted metabolic analysis on the characteristic flavoring compounds showed that the accumulations of free amino acids were enhanced, while catechins, flavonol glycosides, and alkaloids exhibited dynamic changes. This result suggests withering and turning-over process are compatible and collectively regulate the metabolic accumulation and development of flavoring metabolites, facilitating to the development of characteristic quality of Tieguanyin tea.


Assuntos
Aminoácidos , Catequina , Comércio , Flavonóis , Aromatizantes , Catálise , Chá
16.
Food Chem X ; 21: 101139, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38304047

RESUMO

The pile-up processing has a great impact on the flavor of white tea. To investigate the effects of the volatile accumulation of white tea with different piling thickness treatments, tea leaves from different thickness treatments were subjected to sensory quantitative description analysis and ATD-GC-MS detection in this study. As a result, 122 volatile components were identified from white tea with different treatments. A total of 8 key compounds, including isovaleraldehyde, isobutyraldehyde, 2-methyl-butanal, 1-octene-3-ol, linalool, pentanoic acid, hexanal and 1-hexanol were screened out using multivariate statistical analysis, which were characteristic components of grassy, floral-fruity, pekoe aroma and sweet flavors. The results of the selected key characteristic volatile compounds were consistent with the sensory quantitative description. The aroma of mid-pile dried tea (MD) was exhibited a harmonious and pleasant overall flavor. This study provides a novel insight into the accumulation of volatile during the withering step of white tea production.

17.
Front Nutr ; 10: 1026054, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36713086

RESUMO

Background and aims: Although the association between low muscle mass and the risk of non-alcoholic fatty liver disease is well-known, it has not been explored in viscerally obese populations by gender. Besides, whether low muscle mass still increases the NAFLD risk in subjects with visceral obesity, independent of obesity, is still unknown. The aim of this study was to explore the gender-specific association between low muscle mass and the risk of non-alcoholic fatty liver disease (NAFLD) in subjects with visceral obesity. Methods: Overall, 1,114 participants aged 19-89 years were recruited in this retrospective study. Liver disease was diagnosed by hepatic ultrasound. Skeletal muscle mass was estimated by bioimpedance analysis and defined by the appendicular skeletal muscle index (ASMI). Gender-specific differences in the ASMI value were compared between NAFLD and control groups. Restricted cubic spline and multivariate logistic regression were performed to analyze the association (stratified by gender and age) between the ASMI and the risk of NAFLD, respectively. Results: Middle-aged females (40-60 years) and males (of any age) with NAFLD had a significantly lower ASMI compared with controls (P-value < 0.05). An inverse linear association was found between the ASMI and risk of NAFLD (all P fornon-linearity > 0.05). Lower quartiles of the ASMI conferred independent risk of NAFLD compared to higher quartiles (all P for trend < 0.001). Low muscle mass conferred a higher risk of NAFLD in middle-aged females (adjusted odds ratio = 2.43, 95% confidence interval: 1.19-4.95) and males [18-39 years: 3.76 (1.79-7.91); 40-60 years: 4.50 (2.16-9.39); and >60 years: 4.10 (1.13-14.84)]. Besides, Low muscle mass and low muscle mass with obesity increase the risk of developing NAFLD, independent of obesity. Conclusion: Among those with visceral obesity, low muscle mass increased the risk of NAFLD in males of any age, and middle-aged females, this may be explained by the postmenopausal decline in estrogen.

18.
Food Chem X ; 20: 100952, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-37920364

RESUMO

To interpret the formation characteristic flavor during oolong tea manufacturing process, the dynamic changes of key flavor components in samples from various processing steps of Tieguanyin oolong tea production were investigated using widely-targeted metabolomic and the transcriptomic approaches. As a result, a total of 1078 metabolites were determined, of which 62 compounds were identified as biomarkers significantly changed over the manufacturing process. Quantitative determination of the total 50,343 transcripts showed 7480 of them were co-expressed different genes. Glutamic acid served as a critical metabolism hub and a signaling molecule for diverse stress responses. Additionally, the targeted quantification results showed that the contents of catechins and xanthine alkaloids in dried tea were dramatically decreased by 20.19% and 7.15% respectively than those in fresh leaves, which potentially contributed to the alleviation of astringent or bitter palates, promoting the characteristic mellow and rich flavor of Tieguanyin oolong tea.

19.
Food Res Int ; 166: 112591, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36914346

RESUMO

Epigallocatechin-3-gallate (EGCG), a flavoured and healthy compounds in tea, is affected by the ecological factors. However, the biosynthetic mechanisms of EGCG in response to the ecological factors remian unclear. In this study, a response surface method with a Box-Behnken design was used to investigate the relationship between EGCG accumulation and ecological factors; further, integrative transcriptome and metabolome analyses were performed to explore the mechanism underlying EGCG biosynthesis in response to environmental factors. The optimal environmental conditions obtained for EGCG biosynthesis were as follows: 28℃, 70 % relative humidity of the substrate, and 280 µmol·m-2·s-1 light intensity; the EGCG content was increased by 86.83 % compared to the control (CK1). Meanwhile, the order of EGCG content in response to the interaction of ecological factors was as follows: interaction of temperature and light intensity > interaction of temperature and relative humidity of the substrate > interaction of light intensity and relative humidity of the substrate, indicating that temperature was the dominant ecological factors. EGCG biosynthesis in tea plants was found to be comprehensively regulated by a series of structural genes (CsANS, CsF3H, CsCHI, CsCHS, and CsaroDE), miRNAs (miR164, miR396d, miR5264, miR166a, miR171d, miR529, miR396a, miR169, miR7814, miR3444b, and miR5240), and transcription factors (MYB93, NAC2, NAC6, NAC43, WRK24, bHLH30, and WRK70); further, the metabolic flux was regulated and converted from phenolic acid to the flavonoid biosynthesis pathway based on accelerated consumption of phosphoenolpyruvic acid, d-erythrose-4-phosphate, and l-phenylalanine in response to ambient changes in temperature and light intensity. Overall, the results of this study reveal the effect of ecological factors on EGCG biosynthesis in tea plants, providing novel insights for improving tea quality.


Assuntos
Camellia sinensis , Camellia sinensis/química , Transcriptoma , Metaboloma , Chá/química
20.
Foods ; 12(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38231828

RESUMO

Catechins are the major flavor substances in teas, which have a variety of health effects; however, high catechin and high sensory quality are a pair of contradictions that are difficult to coordinate. To explore the processing procedure with high catechins and high sensory quality, a single-factor processing experiment was carried out over the processing production of oolong tea. Combined with orthogonal partial least square discriminant analysis (OPLS-DA), correlation analysis, and principal component analysis (PCA), the optimal production procedure for oolong tea is as follows: red light withering for 8 h, leaf rotating for 10 min with a total standing time for 8 h, drum roasting for 5 min at 290 °C, low-temperature rolling (flattening at 4 °C for 5 min, without pressure for 1 min and under pressure for 5 min), microwave drying (800 W for 7.5 min). This study demonstrates a significant increase in the retention of catechins, which contributes to the mellow and brisk tastes of oolong tea, addressing the challenge of catechin content and sensory quality. Our study provides a novel insight into the relationship between the oolong tea processing and flavor formation.

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