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1.
Heliyon ; 9(11): e21919, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38028004

RESUMO

Background: Evidence on the potential negative health effects of short working hours remains limited. This study aimed to investigate the association between short working hours and perceived stress in a population-based sample from China. Methods: This cross-sectional study included 4368 participants aged 18-65 years from the China Health and Nutrition Surveys (CHNS) 2015. Working hours were categorized into <35, 35-40, 41-54, and ≥55 h/week. Perceived stress was assessed using the Perceived Stress Scale-14 (PSS-14). Results: Of the 4368 participants, 817 (18.7 %) reported short working hours (<35 h/week) and 1817 (41.6 %) reported perceived stress. Short working hours were associated with higher perceived stress compared to standard working hours (35-40 h/week) (Adjusted odds ratios (AOR) = 1.25, 95 % confidential intervals (CI): 1.04-1.51). Stratified analysis showed that short working hours were significantly associated with more perceived stress in subjects aged 36-50 years (AOR = 1.43, 95 % CI: 1.16-1.70), while long working hours (≥55 h/week) were significantly related to less perceived stress among low-income subjects (AOR = 0.56, 95 % CI: 0.33-0.94). Reduced income partially mediated the effects of short working hours on perceived stress (indirect effects = -0.002, 95 % CI: -0.007∼-0.001). Conclusion: Reduced working hours may be associated with increased risk of perceived stress in China, particularly among people aged 36-50 years and those with low income. Reduced income may be a possible reason for the increased perceived stress caused by short working hours. Future longitudinal studies are needed to examine these relationships and to explore mechanisms.

2.
J Phys Chem Lett ; 14(20): 4760-4765, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37184776

RESUMO

The adsorption energy of adsorbed molecules on single-atom catalysts is a key indicator of the catalytic activity of the catalysts. Developing a generic and interpretable structure-property prediction model from numerous influencing factors is a challenging task. In this work, we constructed a machine learning (ML) model from first-principles calculations of the adsorption energy data of O2 on Ni(II), Co(II), Cu(II), Fe(II), Fe(III), and Mn(II) single-atom catalysts supported on 15 different N-C substrates under various spin states. A mathematic formula is proposed to predict the adsorption energy by a novel data-driven descriptor derived from physically meaningful factors such as geometric distances and atomic charges. This data-driven descriptor is relevant to only the geometrical configuration of the adsorbate, while the parameters in the linear formulas contain only substrate-specific information. This ML model with the ability to decouple variables will greatly advance the understanding of metal-N-C single-atom catalysts and help in the design of new substrates to modulate catalytic activity.

3.
Angew Chem Int Ed Engl ; 62(18): e202301925, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-36866977

RESUMO

Spin manipulation of transition-metal catalysts has great potential in mimicking enzyme electronic structures to improve activity and/or selectivity. However, it remains a great challenge to manipulate room-temperature spin state of catalytic centers. Herein, we report a mechanical exfoliation strategy to in situ induce partial spin crossover from high-spin (s=5/2) to low-spin (s=1/2) of the ferric center. Due to spin transition of catalytic center, mixed-spin catalyst exhibits a high CO yield of 19.7 mmol g-1 with selectivity of 91.6 %, much superior to that of high-spin bulk counterpart (50 % selectivity). Density functional theory calculations reveal that low-spin 3d-orbital electronic configuration performs a key function in promoting CO2 adsorption and reducing activation barrier. Hence, the spin manipulation highlights a new insight into designing highly efficient biomimetic catalysts via optimizing spin state.

4.
Front Nutr ; 7: 596823, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33392238

RESUMO

Theacrine, i.e., 1,3,7,9-tetramethyluric acid, is one of the major purine alkaloids found in leaf of a wild tea plant species Camellia kucha Hung T. Chang. Theacrine has been attracted great attentions academically owing to its diverse health benefits. Present review examines the advances in the research on the health beneficial effects of theacrine, including antioxidant effect, anti-inflammatory effect, locomotor activation and reducing fatigue effects, improving cognitive effect, hypnotic effect, ameliorating lipid metabolism and inhibiting breast cancer cell metastasis effect. The inconsistent results in this research field and further expectations were also discussed.

5.
Food Chem ; 311: 125894, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31787396

RESUMO

This work aims to use defatted rice bran albumin (RBA) for delivering epigallocatechin gallate (EGCg). The mode of RBA particle size shifted from 142 nm to 164 nm upon interaction with EGCg. Hydrophobic interaction is the major force between EGCg and RBA resulted in the formation of EGCg-RBA complex based on fluorescence quenching. Upon incorporation into RBA, the recovery of EGCg in pH 7.4 phosphate buffer was elevated by 2 folds. The recovery of EGCg in EGCg-RBA was 18.9% after 2 h intestinal digestion, being higher than 7.6% of native EGCg. The pretreatments of HT-29 cells with EGCg, RBA and EGCg-RBA significantly repressed the transcriptional activation of mitogen-activated protein kinase 14, nuclear transcription factor-κB, and activators of transcription 3 as stimulated with interleukin-1ß afterwards, leading to attenuated expressions of corresponding downstream genes. Antioxidant ability importantly functioned in anti-inflammation. RBA is a promising vehicle with inherent anti-inflammatory property for stabilizing and delivering EGCg.


Assuntos
Albuminas/química , Catequina/análogos & derivados , Oryza/metabolismo , Antioxidantes/metabolismo , Catequina/química , Catequina/farmacologia , Células HT29 , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Proteína Quinase 14 Ativada por Mitógeno/genética , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Tamanho da Partícula , Ativação Transcricional/efeitos dos fármacos
6.
Molecules ; 23(3)2018 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-29495349

RESUMO

As the population ages, neurodegenerative diseases such as Parkinson's disease (PD) and Alzheimer's disease (AD) impose a heavy burden on society and families. The pathogeneses of PD and AD are complex. There are no radical cures for the diseases, and existing therapeutic agents for PD and AD have diverse side effects. Tea contains many bioactive components such as polyphenols, theanine, caffeine, and theaflavins. Some investigations of epidemiology have demonstrated that drinking tea can decrease the risk of PD and AD. Tea polyphenols can lower the morbidity of PD and AD by reducing oxidative stress and regulating signaling pathways and metal chelation. Theanine can inhibit the glutamate receptors and regulate the extracellular concentration of glutamine, presenting neuroprotective effects. Additionally, the neuroprotective mechanisms of caffeine and theaflavins may contribute to the ability to antagonize the adenosine receptor A2AR and the antioxidant properties, respectively. Thus, tea bioactive components might be useful for neuronal degeneration treatment in the future. In the present paper, the neuro protection and the mechanisms of tea and its bioactive components are reviewed. Moreover, the potential challenges and future work are also discussed.


Assuntos
Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Chá/química , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Biflavonoides/química , Biflavonoides/farmacologia , Cafeína/química , Cafeína/farmacologia , Catequina/química , Catequina/farmacologia , Glutamatos/química , Glutamatos/farmacologia , Interações Ervas-Drogas , Humanos , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/epidemiologia , Doenças Neurodegenerativas/etiologia , Doenças Neurodegenerativas/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Compostos Fitoquímicos/uso terapêutico , Extratos Vegetais/uso terapêutico , Polifenóis/química , Polifenóis/farmacologia , Transdução de Sinais/efeitos dos fármacos
7.
Protein Cell ; 7(5): 325-37, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27085723

RESUMO

G protein-coupled receptors (GPCRs) are involved in all human physiological systems where they are responsible for transducing extracellular signals into cells. GPCRs signal in response to a diverse array of stimuli including light, hormones, and lipids, where these signals affect downstream cascades to impact both health and disease states. Yet, despite their importance as therapeutic targets, detailed molecular structures of only 30 GPCRs have been determined to date. A key challenge to their structure determination is adequate protein expression. Here we report the quantification of protein expression in an insect cell expression system for all 826 human GPCRs using two different fusion constructs. Expression characteristics are analyzed in aggregate and among each of the five distinct subfamilies. These data can be used to identify trends related to GPCR expression between different fusion constructs and between different GPCR families, and to prioritize lead candidates for future structure determination feasibility.


Assuntos
Receptores Acoplados a Proteínas G/metabolismo , Animais , Biologia Computacional , Cristalografia por Raios X , Expressão Gênica , Humanos , Plasmídeos/genética , Plasmídeos/metabolismo , Domínios Proteicos , Receptores Adrenérgicos beta 1 , Receptores Acoplados a Proteínas G/classificação , Receptores Acoplados a Proteínas G/genética , Receptores Odorantes/metabolismo , Receptores Purinérgicos P1/genética , Receptores Purinérgicos P1/metabolismo , Células Sf9 , Spodoptera
8.
PLoS One ; 10(7): e0131711, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26158525

RESUMO

Nacrein is the first identified and widely investigated molluscan matrix protein and is considered to play an important role in the shell formation of the pearl oyster, Pinctada fucata. Here, we investigate the effect of the NF-κB signalling pathway on Nacrein gene expression in P. fucata to elucidate the mechanisms involved in shell formation. Inhibition of NF-κB signalling decreased Nacrein promoter-dependent luciferase activity. However, co-transfection of the Nacrein promoter vector with Pf-IKK or Pf-Rel expression plasmids could enhance luciferase activity, thus proving NF-κB signalling could regulate the transcriptional activity of the Nacrein promoter. Gene silencing by RNA interference and subsequent observation of the inner surface of the nacreous layer of oyster shells by SEM, showed that suppression of the gene Pf-Rel lead to a partial inhibition of Nacrein expression, not only at the mRNA level but also at the protein level. The inner surface of the shells became abnormal. Electrophoretic mobility shift assays (EMSAs) revealed that Pf-Rel could directly bind to the relative sites of the Nacrein promoter. These results confirm that an important component of the NF-κB signalling pathway, Pf-Rel, can directly bind the Nacrein promoter in P. fucata, and regulate its transcription and shell formation.


Assuntos
Anidrases Carbônicas/genética , Expressão Gênica , NF-kappa B/metabolismo , Pinctada/genética , Transdução de Sinais , Exoesqueleto/metabolismo , Exoesqueleto/ultraestrutura , Animais , Sequência de Bases , Sítios de Ligação/genética , Anidrases Carbônicas/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Luciferases/genética , Luciferases/metabolismo , Microscopia Eletrônica de Varredura , NF-kappa B/genética , Pinctada/metabolismo , Pinctada/ultraestrutura , Regiões Promotoras Genéticas/genética , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ativação Transcricional
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