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1.
Plants (Basel) ; 13(12)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38931057

RESUMO

This research aimed to explore the diverse phenotypic characteristics of moso bamboo in China and pinpoint essential characteristics of moso bamboo. In this study, 63 grids were selected using the grid method to investigate 28 phenotypic traits of moso bamboo across the entire distribution area of China. The results suggest that the phenotypic traits of moso bamboo exhibit rich diversity, with coefficients of variation ranging from 5.87% to 36.57%. The phenotypic traits of moso bamboo showed varying degrees of correlation. A principal component analysis was used to identify seven main phenotypic trait indicators: diameter at breast height (DBH), leaf area (LA), leaf weight (LW), branch-to-leaf ratio (BLr), leaf moisture content (Lmc), wall-to-cavity ratio (WCr), and node length at breast height (LN), which accounted for 81.64% of the total information. A random forest model was used, which gave good results to validate the results. The average combined phenotypic trait value (D-value) of most germplasm was 0.563. The highest D-value was found in Wuyi 1 moso in Fujian (0.803), while the lowest D-value was observed in Pingle 2 moso in Guangxi (0.317). The clustering analysis of phenotypic traits classified China's moso bamboo germplasm into four groups. Group I had the highest D-value and is an important candidate germplasm for excellent germplasm screening.

3.
Mech Ageing Dev ; 218: 111902, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38218462

RESUMO

Senescent cells are known to be accumulated in aged organisms. Although the two main characteristics, cell cycle arrest (for dividing cells) and secretion of senescence-associated secretory phenotype (SASP) factors, have been well described, the lack of sufficient senescent markers and incomplete understanding of mechanisms have limited the progress of the anti-senescence field. Calcium transferred from the endoplasmic reticulum (ER) via inositol 1, 4, 5-trisphosphate receptor type 2 (ITPR2) to mitochondria has emerged as a key player during cellular senescence and aging. However, the internal regulatory mechanisms, particularly those of endogenous molecules, remain only partially understood. Here we identified miRNA-129 (miR-129) as a direct repressor of ITPR2. Interestingly, miR-129 controlled a cascade of intracellular calcium signaling, mitochondrial membrane potential (MMP), reactive oxygen species (ROS), DNA damage, and consequently cellular senescence through ITPR2 and mitochondrial calcium uniporter (MCU). In addition, miR-129 was repressed in different senescence models and delayed bleomycin-induced cellular senescence. Importantly, intraperitoneal injection of miR-129 partly postponed bleomycin-accelerated lung aging and natural aging markers as well as reduced immunosenescence markers in mice. Altogether, these findings demonstrated that miR-129 regulated cellular senescence and aging markers via intracellular calcium signaling by directly targeting ITPR2.


Assuntos
MicroRNAs , Animais , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Cálcio/metabolismo , Mitocôndrias/metabolismo , Senescência Celular , Retículo Endoplasmático/metabolismo , Sinalização do Cálcio , Bleomicina/metabolismo
5.
Front Psychol ; 14: 1131387, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37260959

RESUMO

Many studies emphasize the need of verbally representing pictorial metaphors, but few have empirically investigated whether and how the particular verbalization form match different types of pictorial metaphors. Using evoked response potentials (ERP), a 3 (pictorial structure: fusion, juxtaposition, literal image) × 2 [verbalization form: A(is) B, A(is like) B] within-group experiment was conducted among 36 participants. ERPs were time-locked to the onset of the verb [/(is/is like)] of the metaphor sentence that follows a pictorial metaphor to detect the verbo-pictorial incongruity in metaphor comprehension. The incongruity-based ERP analysis showed that pictorial metaphors, when verbalized in two forms, all induced frontal N1 effect, regardless of pictorial structures, only with a larger N1 amplitude for literal images in "A(is) B." A central stronger P2 was observed in "A(is like) B" for three structures. Despite a general elicitation of posterior P3 in all conditions, a larger P3 was found for juxtapositions verbalized in "A(is like) B" and for literal images verbalized in "A(is) B." There was no significant difference between two verbalization forms for fusion-structured pictorial metaphors. These findings suggest: (1) verbo-pictorial metaphors could induce incongruity-based attention; (2) higher verbo-pictorial semantic congruity and relatedness, indexed by stronger P2 and P3, confirmed "A(is like) B" to be the more effective verbalization form in representing pictorial metaphors, specifically for juxtaposition-structured pictorial metaphors; (3) for non-metaphor advertising pictures, verbal metaphor showed an interference effect. The study not only reveals the neuro-cognitive mechanism of processing verbo-pictorial metaphors, but also offers neural reference for the design of effective multi-modal metaphor by finding an optimal match between PMs and verbalization forms.

6.
Oxid Med Cell Longev ; 2022: 2286598, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35965680

RESUMO

The aim of the study was to investigate the clinical effects of abdominal massage on patients with type 2 diabetes mellitus (T2DM) and its influence on the intestinal microflora. We conducted a randomized, controlled clinical trial. A total of 60 patients with T2DM, who met the inclusion criteria, were randomly allocated to the control group, the routine massage group, and the abdominal massage group. The control group received health education and maintained their hypoglycemic drug treatment plan. The routine massage group and the abdominal massage group received different massage interventions. In addition to glucose and lipid metabolism indicators, we quantitatively analyzed the gut microbiota to assess the effects of massage on the intestinal microflora of patients with T2DM. Compared with the control group, the abdominal massage improved levels of glycated hemoglobin, total cholesterol, Enterobacter, and Bifidobacteria with significant differences (P = 0.02, P = 0.03, P = 0.03, and P = 0.03). The comparison within group showed that the levels of the four bacterial genera in the abdominal massage group revealed significant differences before and after treatment (P = 0.006, P < 0.001, P < 0.001, and P = 0.002). The comparison between the routine massage group and the abdominal massage group was not significantly different in all levels of test indices. The abdominal massage group regulated levels of Enterobacter and Lactobacilli to a greater extent than the routine massage group. Additionally, abdominal massage decreased Enterococcus levels. The results of this study showed that abdominal massage has clinical advantages over routine massage. Specifically, this intervention may correct microflora disturbances to a certain extent.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Glicemia , Diabetes Mellitus Tipo 2/terapia , Hemoglobinas Glicadas , Humanos , Massagem/métodos
7.
J Environ Public Health ; 2022: 4848738, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35774192

RESUMO

Based on the role separation scenario in which students need parental support, this paper explores the effect of parents' attitude on secondary school students' online learning. Through structural equation model analysis and regression analysis of 745 valid responses to a questionnaire, the data results show that parents' subjective dimension includes perceived gain and perceived loss, and social factor dimension includes teachers' influence and online comments. Perceived value is the key influencing factor of parents' attitude towards secondary school students in online learning platform. Perceived usefulness and platform information influence parents' attitude positively and significantly, while perceived risk influences parents' attitude negatively and significantly. In the dimension of social factors, teachers' influence positively influences parents' attitude, and online comments modulate the influence of perceived value on parents' attitude.


Assuntos
Educação a Distância , Atitude , Humanos , Estudantes , Inquéritos e Questionários
8.
Entropy (Basel) ; 22(6)2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-33286391

RESUMO

With the development of credit businesses, privacy data leakage and data accuracy in loan transactions among different banks tend to be worrisome issues hindering the prosperity of the industry. To address the problem, we propose a blockchain-based cross-bank over-loan prevention (CBOL-ring) mechanism, which ensures that, on the one hand, the plaintext of loan transactions cannot be access to neither participants on the nodes except the bank that handles loan/repayment requests, so as to prevent the borrower from loaning without revealing their privacy data; on the other hand, the other participants are able to prove the effectiveness of the plaintexts through checking the ciphertexts on the blockchain. In addition, we propose a blockchain-based cross-bank over-loan prevention mechanism with low communication volume (CBOL-bullet), which reduces the size of the range proof generated by the BBCBOLP mechanism, thereby reducing the size of the communication volume and saving resources during the data transmission process. Finally, we analyze the security and performance of the two mechanisms, and compare the communication volume of the two mechanisms.

9.
Entropy (Basel) ; 22(7)2020 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-33286484

RESUMO

As the blockchain 2.0 platform, Ethereum's turing complete programming language and smart contract components make it play an important role in the commercialization of blockchain. With the further development of blockchain applications, the privacy and security issues of Ethereum have gradually emerged. To solve this problem, we proposed a blockchain privacy protection model called RZcash in the previous work. It implements the dynamically updateable and verifiable hiding of the asset information in Ethereum, namely the account balance and transaction amount. However, RZcash does not pay attention to the key redundancy problem that may be caused by the creation of secret accounts. In addition, the large size of proofs gives it high communication costs. In response to these problems, we further improve RZcash. For the key redundancy problem, we construct a new signature scheme based on the ciphertext equivalent test commitment. Moreover, we use the Schnorr signature and bulletproof to improve the corresponding proof scheme in RZcash, thereby reducing the size of proof. Based on these improvements, we propose a decentralized payment system, called RZcoin, based on Ethereum. Finally, we implement the algorithm model of RZcoin and evaluate its security and performance. The results show that RZcoin has higher security and Lower communication cost than RZcash.

10.
Entropy (Basel) ; 22(11)2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33287014

RESUMO

Identity-based encryption (IBE), and its hierarchical extension (HIBE), are interesting cryptographic primitives that aim at the implicit authentication on the users' public keys by using users' identities directly. During the past several decades, numerous elegant pairing-based (H)IBE schemes were proposed. However, most pairing-related security assumptions suffer from known quantum algorithmic attacks. Therefore, the construction of lattice-based (H)IBE became one of the hot directions in recent years. In the setting of most existing lattice-based (H)IBE schemes, each bit of a user's identity is always associated with a parameter matrix. This always leads to drastic but unfavorable increases in the sizes of the system public parameters. To overcome this issue, we propose a flexible trade-off mechanism between the size of the public parameters and the involved computational cost using the blocking technique. More specifically, we divide an identity into l' segments and associate each segment with a matrix, while increasing the lattice modulo slightly for maintaining the same security level. As a result, for the setting of 160-bit identities, we show that the size of the public parameters can be reduced by almost 89.7% (resp. 93.8%) while increasing the computational cost by merely 5.2% (resp. 12.25%) when l' is a set of 16 (resp. 8). Finally, our IBE scheme is extended to an HIBE scheme, and both of them are proved to achieve the indistinguishability of ciphertexts against adaptively chosen identity and chosen plaintext attack (IND-ID-CPA) in the standard model, assuming that the well-known ring learning with error (RLWE) problem over the involved ideal lattices is intractable, even in the post-quantum era.

11.
Chem Commun (Camb) ; 56(9): 1397-1400, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31912815

RESUMO

NAMI-A is highly reactive to Sp1, a tumor metastasis related protein, resulting in the perturbation of the protein structure and disruption of the DNA recognition of Sp1. Interestingly, Sp1 is more susceptible than other zinc finger proteins to NAMI-A, suggesting that Sp1 could be the anti-metastasis target of NAMI-A.


Assuntos
Antineoplásicos/química , Dimetil Sulfóxido/análogos & derivados , Compostos Organometálicos/química , Compostos de Rutênio/química , Fator de Transcrição Sp1/química , DNA/metabolismo , Dimetil Sulfóxido/química , Glutationa/química , Ligação Proteica , Multimerização Proteica/efeitos dos fármacos , Estrutura Secundária de Proteína/efeitos dos fármacos , Desdobramento de Proteína/efeitos dos fármacos , Fator de Transcrição Sp1/metabolismo
12.
Rapid Commun Mass Spectrom ; 33(19): 1502-1511, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31151135

RESUMO

RATIONALE: Previous studies found that charge state could affect both specific and nonspecific binding of protein-metal ion interactions in nanoelectrospray ionization mass spectrometry (nESI-MS). However, the two kinds of interactions have been studied individually in spite of the problem that they often coexist in the same system. Thus, it is necessary to study the effects of charge state on specific and nonspecific protein-metal ion interactions in one system to reveal more accurate binding state. METHODS: The HIV-1 nucleocapsid protein (NCp7(31-55)) which can bind specifically and nonspecifically to Zn2+ served as the model to show the charge-dependent protein-metal ion interactions. Hydrogen/deuterium exchange (HDX) and photodissociation (PD) were used to demonstrate that specific binding state was correlated with protein structure. In addition to NCp7(31-55), three other model proteins were used to investigate the reason for the charge-dependent nonspecific binding. RESULTS: For specific binding, we proposed that protein ions with different charge states had different conformations. The HDX results showed that labile protons in the NCp7(31-55)-Zn complex were exchanged in a charge-state-dependent way. The PD experiments revealed differential fragment yields for different charge states. For nonspecific binding, higher charge states had more Zn2+ additions, but less SO4 2- additions. The effects of charge states on nonspecific binding levels were entirely the opposite for Zn2+ and SO4 2- . These results could reveal that the nonspecific binding was caused by electrostatic interaction. CONCLUSIONS: For specific binding, NCp7(31-55) with lower charge states have folding and undenatured structures. The binding states of lower charge states can better reflect more native binding states. For nonspecific binding, when multiple metal ions adduct to proteins, the proteins have more net positive charges, which tend to generate higher charge ions during electrospray.


Assuntos
Meliteno/química , Quinase de Cadeia Leve de Miosina/química , Proteínas do Nucleocapsídeo/química , Zinco/química , HIV-1/química , Íons/química , Nanotecnologia , Ligação Proteica , Espectrometria de Massas por Ionização por Electrospray/métodos , Eletricidade Estática
13.
Metallomics ; 10(11): 1564-1569, 2018 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-30259936

RESUMO

Arsenic trioxide (ATO) is used in the clinic for the treatment of acute promyelocytic leukemia by targeting the protein PML. However, many zinc-finger proteins could also be reactive to arsenic in cells. Here we found that ATO preferentially binds to the ring-finger domain of PML in a protein mixture with zinc-finger domains. These results provide the molecular basis of the target selection of ATO in cells.


Assuntos
Antineoplásicos/metabolismo , Trióxido de Arsênio/metabolismo , Proteína da Leucemia Promielocítica/metabolismo , Dedos de Zinco , Humanos
14.
Anal Chem ; 90(13): 7997-8001, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29894165

RESUMO

Sequential unfolding of monomeric proteins is important for the global understanding of local conformational elements (e.g., secondary structures and domain connections) within those protein assemblies. Ion mobility-mass spectrometry (IM-MS) is an emerging and promising technique for probing gradual protein structural perturbations in the gas phase. However, it is still challenging to track sequential unfolding in the solution phase. Here, we extended IM-MS to track in-solution sequential unfolding of monomeric proteins having single and/or multidomains. The present method combines ultrafast local heating effect (LHE)-driven sequential unfolding with IM-MS identification. Protein sequential unfolding in solution is demonstrated by the rapid and controllable IM-MS data switch between native and gradually unfolded states. Our results show that LHE induces gradual protein conformational transitions associated with biological functions, where IM-MS tracks the sequential unfolding of monomeric proteins.


Assuntos
Espectrometria de Mobilidade Iônica/métodos , Desdobramento de Proteína , Temperatura , Soluções Tampão , Calmodulina/química , Modelos Moleculares , Conformação Proteica , Soluções , Fatores de Tempo
15.
Anal Chem ; 90(5): 3409-3415, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29406694

RESUMO

In situ living cell protein analysis would enable the structural identification and functional interrogation of intracellular proteins in native cellular environments. Previously, we have presented an in situ mass spectrometry (MS) strategy to identify protein and protein/metal ion complex with relatively small molecular weight ( Anal. Chem. 2016, 88, 10860-10866). However, it is still challenging to directly identify larger proteins and protein/ligand complexes in cell, due to numerous nonspecific bindings of ligands, solvents, and other cellular constituents. Here we present a versatile single-step mass spectrometric strategy, "in-cell" mass spectrometry ("in-cell" MS), for in situ protein identification and dynamic protein-ligand interaction monitoring directly from living cells. "In-cell" MS combined all-ion-fragmentation mode with our previous method; thus, on a high-resolution MS instrument, we can greatly improve the signal/noise ratio of the larger proteins and protein/ligand complexes. Meanwhile, we also achieved a much wider mass range for protein complex and detection of 17 proteins with molecular weight ranging from 4 to 44 kDa. In addition, "in-cell" MS could also monitor dynamic protein interactions in living cells. Calcium-regulated calmodulin-melittin interaction was tested to demonstrate the proof of concept. "In-cell" MS provides an alternative for in situ analysis of living cells, which might contribute to rapid protein analysis and quality control in biochemistry laboratories, protein engineering, and even protein industry.


Assuntos
Espectrometria de Massas/métodos , Proteínas/análise , Calmodulina/análise , Sobrevivência Celular , Escherichia coli/química , Conformação Proteica , Proteômica/métodos , Proteínas Recombinantes/análise
16.
J Am Soc Mass Spectrom ; 28(12): 2658-2664, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28887698

RESUMO

Specific protein-metal interactions (PMIs) fulfill essential functions in cells and organic bodies, and activation of these functions in vivo are mostly modulated by the complex environmental factors, including pH value, small biomolecules, and salts. Specifically, the role of salts in promoting specific PMIs and their competition among various metals has remained untapped mainly due to the difficulty to distinguish nonspecific PMIs from specific PMIs by classic spectroscopic techniques. Herein, we report Hofmeister salts differentially promote the specific PMIs by combining nanoelectrospray ionization mass spectrometry and spectroscopic techniques (fluorescence measurement and circular dichroism). Furthermore, to explore the influence of salts in competitive binding between metalloproteins and various metals, we designed a series of competitive experiments and applied to a well-defined model system, the competitive binding of zinc (II) and arsenic (III) to holo-promyelocytic leukemia protein (PML). These experiments not only provided new insights at the molecular scale as complementary to previous NMR and spectroscopic results, but also deduced the relative binding ability between zinc finger proteins and metals at the molecular scale, which avoids the mass spectrometric titration-based determination of binding constants that is frequently affected and often degraded by variable solution conditions including salt contents. Graphical Abstract ᅟ.


Assuntos
Metais/metabolismo , Proteína da Leucemia Promielocítica/metabolismo , Sais/metabolismo , Dedos de Zinco , Arsênio/metabolismo , Dicroísmo Circular , Humanos , Ligação Proteica , Espectrometria de Massas por Ionização por Electrospray , Zinco/metabolismo
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