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1.
RSC Adv ; 14(18): 12864-12872, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38650686

RESUMEN

Ferroptosis is a newly discovered iron-dependent form of regulated cell death associated with high levels of hydroxyl radical (˙OH) production. Meanwhile, lysosome dysfunction has been shown to be one of the causes of ferroptosis. Although a variety of ˙OH-responsive fluorescent probes have been developed for detecting intracellular ˙OH in living cells, there are still only few lysosome-targeted probes to monitor the variation in lysosomal ˙OH levels during ferroptosis. Herein, we report a novel ˙OH-specific fluorescent probe HCy-Lyso, which is composed of the hydrocyanine and morpholine moiety. Upon treatment with ˙OH, its hydrocyanine unit was converted to the corresponding cyanine group, thus leading to a large π-conjugation extension of HCy-Lyso, accompanied by a significant fluorescence off-on response. Moreover, after reacting with ˙OH in an acidic environment, the protonation product of HCy-Lyso exhibits a higher fluorescence enhancement, which is suitable for detecting lysosomal ˙OH variation. HCy-Lyso has been utilized for imaging endogenous ˙OH in living cells under phorbol myristate acetate (PMA) stimuli and monitoring the changes in lysosomal ˙OH levels during ferroptosis. Thus, our study proposes a new strategy to design lysosome-targeted and ˙OH-responsive fluorescent probes to investigate the relationship between lysosomes and ferroptosis.

2.
Environ Pollut ; 349: 123856, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38556152

RESUMEN

BACKGROUND: Polycyclic aromatic hydrocarbons (PAHs) are well-acknowledged pro-inflammatory chemicals, but their associations with blood cell-based inflammatory biomarkers need further investigation. Moreover, the effects and mechanisms of essential metals on PAH-related inflammation remain poorly understood. OBJECTS: To elucidate the associations of PAHs on inflammatory biomarkers, as well as the effects and mechanisms of essential metals on these associations. METHODS: A cross-sectional study was conducted on 1388 coke oven workers. We analyzed the modification effects of key essential metal(s) on PAHs-inflammatory biomarkers associations. To explore the possible mechanisms from an inflammation perspective, we performed a bioinformatic analysis on the genes of PAHs and essential metals obtained from the Comparative Toxicogenomics Database (CTD) and performed a mediation analysis. RESULTS: We observed associations of PAHs and essential metals with lymphocyte-to-monocyte ratio (LMR) (P < 0.05). PAH mixtures were inversely associated with LMR (ßQGC-index = -0.18, P < 0.001), with 1-hydroxypyrene (1-OH-Pyr) being the most prominent contributor (weight = 63.37%), whereas a positive association between essential metal mixtures and LMR was observed (ßQGC-index = 0.14, P < 0.001), with tin being the most significant contributor (weight = 51.61%). An inverse association of 1-OH-Pyr with LMR was weakened by increased tin exposure (P < 0.05). The CTD database showed that PAHs and tin compounds co-regulated 22 inflammation-associated genes, but they regulated most genes in opposite directions. Further identified the involvement of oxidative stress and mediation analysis showed that the mediation effect of 8-hydroxydeoxyguanosine (8-OHdG) on 1-OH-Pyr-LMR association presented heterogeneity between low and high tin tertile groups (I2 = 37.84%). CONCLUSION: 1-OH-Pyr and tin were significantly associated with LMR. Modification effects indicated that the inverse association of 1-OH-Pyr with LMR was mitigated with an increase in tin. The mediation effect of 8-OHdG on the inverse association of 1-OH-Pyr with LMR may be partially dependent on tin.


Asunto(s)
Biomarcadores , Inflamación , Exposición Profesional , Hidrocarburos Policíclicos Aromáticos , Hidrocarburos Policíclicos Aromáticos/toxicidad , Humanos , Biomarcadores/sangre , Estudios Transversales , Adulto , Masculino , Metales , Coque , Persona de Mediana Edad
3.
Theor Appl Genet ; 137(4): 90, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38555318

RESUMEN

KEY MESSAGE: Fine mapping of the maize QTL qSRC3, responsible for red silk, uncovered the candidate gene ZmMYB20, which encodes an R2R3-MYB transcription factor, has light-sensitive expression, and putatively regulates genes expression associated with anthocyanin biosynthesis. Colorless silk is a key characteristic contributing to the visual quality of fresh corn intended for market distribution. Nonetheless, the identification of Mendelian trait loci and associated genes that control silk color has been scarce. In this study, a F2 population arising from the hybridization of the single-segment substitution line qSRC3MT1 with red silk, carrying an introgressed allele from teosinte (Zea mays ssp. mexicana), and the recurrent maize inbred line Mo17, characterized by light green silk, was utilized for fine mapping. We found that the red silk trait is controlled by a semi-dominant genetic locus known as qSRC3, and its expression is susceptible to light-mediated inhibition. Moreover, qSRC3 explained 68.78% of the phenotypic variance and was delimited to a 133.2 kb region, which includes three genes. Subsequent expression analyses revealed that ZmMYB20 (Zm00001d039700), which encodes an R2R3-MYB transcription factor, was the key candidate gene within qSRC3. Yeast one-hybrid and dual-luciferase reporter assays provided evidence that ZmMYB20 suppresses the expression of two crucial anthocyanin biosynthesis genes, namely ZmF3H and ZmUFGT, by directly binding to their respective promoter regions. Our findings underscore the significance of light-inhibited ZmMYB20 in orchestrating the spatial and temporal regulation of anthocyanin biosynthesis. These results advance the production of colorless silk in fresh corn, responding to the misconception that fresh corn with withered colored silk is not fresh and providing valuable genetic resources for the improvement of sweet and waxy maize.


Asunto(s)
Antocianinas , Zea mays , Mapeo Cromosómico/métodos , Zea mays/genética , Factores de Transcripción/genética , Estudios de Asociación Genética
4.
ACS Appl Mater Interfaces ; 16(11): 14026-14037, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38447136

RESUMEN

With the rapid development of small-molecule electron acceptors, polymer electron donors are becoming more important than ever in organic photovoltaics, and there is still room for the currently available high-performance polymer donors. To further develop polymer donors with finely tunable structures to achieve better photovoltaic performances, random ternary copolymerization is a useful technique. Herein, by incorporating a new electron-withdrawing segment 2,3-bis(3-octyloxyphenyl)dithieno[3,2-f:2',3'-h]quinoxaline derivative (C12T-TQ) to PM6, a series of terpolymers were synthesized. It is worth noting that the introduction of the C12T-TQ unit can deepen the highest occupied molecular orbital energy levels of the resultant polymers. In addition, the polymer Z6 with a 10% C12T-TQ ratio possesses the highest film absorption coefficient (9.86 × 104 cm-1) among the four polymers. When blended with Y6, it exhibited superior miscibility and mutual crystallinity enhancement between Z6 and Y6, suppressed recombination, better exciton separation and charge collection characteristics, and faster hole transfer in the D-A interface. Consequently, the device of Z6:Y6 successfully achieved enhanced photovoltaic parameters and yielded an efficiency of 17.01%, higher than the 16.18% of the PM6:Y6 device, demonstrating the effectiveness of the meta-octyloxy-phenyl-modified dithieno[3,2-f:2',3'-h]quinoxaline moiety to build promising terpolymer donors for high-performance organic solar cells.

5.
Int J Hyg Environ Health ; 256: 114323, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38237548

RESUMEN

Whether adopting healthy lifestyles and maintaining moderate levels of essential metals could attenuate the reduction of heart rate variability (HRV) related to polycyclic aromatic hydrocarbons (PAHs) exposure are largely unknown. In this study, we measured urinary metals and PAHs as well as HRV, and constructed a healthy lifestyle score in 1267 coke oven workers. Linear regression models were used to explore the association of healthy lifestyle score and essential metals with HRV, and interaction analysis was performed to investigate the potential interaction between healthy lifestyle score, essential metals, and PAHs on HRV. Mean age of the participants was 41.9 years (84.5% male). Per one point higher healthy lifestyle score was associated with a 2.5% (95% CI, 1.0%-3.9%) higher standard deviation of all normal to normal intervals (SDNN), 2.1% (95% CI, 0.5%-3.6%) higher root mean square of successive differences in adjacent NN intervals (r-MSSD), 4.3% (95% CI, 0.4%-8.2%) higher low frequency, 4.4% (95% CI, 0.2%-8.5%) higher high frequency, and 4.4% (95% CI, 1.2%-7.6%) higher total power, respectively. Urinary level of chromium was positively associated with HRV indices, with the corresponding ß (95% CI) (%) was 5.17 (2.84, 7.50) for SDNN, 4.29 (1.74, 6.84) for r-MSSD, 12.26 (6.08, 18.45) for low frequency, 12.61 (5.87, 19.36) for high frequency, and 11.31 (6.19, 16.43) for total power. Additionally, a significant interaction was found between healthy lifestyle score and urinary total hydroxynaphthalene on SDNN (Pinteraction = 0.04), and higher level of urinary chromium could attenuate the adverse effect of total hydroxynaphthalene level on HRV (all Pinteraction <0.05). Findings of our study suggest adopting healthy lifestyle and maintaining a relatively high level of chromium might attenuate the reduction of HRV related to total hydroxynaphthalene exposure.


Asunto(s)
Coque , Exposición Profesional , Hidrocarburos Policíclicos Aromáticos , Humanos , Masculino , Adulto , Femenino , Hidrocarburos Policíclicos Aromáticos/orina , Frecuencia Cardíaca , Coque/análisis , Naftoles/análisis , Naftoles/farmacología , Metales/orina , Cromo/análisis , Cromo/farmacología , Estilo de Vida Saludable , Exposición Profesional/análisis
6.
Adv Healthc Mater ; 13(10): e2303192, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38011625

RESUMEN

Exploring the preparation of multifunctional hydrogels from a bionic perspective is an appealing strategy. Here, a multifunctional hydrogel dressing inspired by the characteristics of porous extracellular matrix produced during Acomys wound healing is prepared. These dressings are printed by digital light processing printing of hydrogels composed of gelatin methacrylate, hyaluronic acid methacrylate, and pretreated platelet-rich plasma (PRP) to shape out triply periodic minimal surface structures, which are freeze-dried for long-term storage. These dressings mimic the porous extracellular matrix of Acomys, while the freeze-drying technique effectively extends the storage duration of PRP viability. Through in vivo and in vitro experiments, the biomimetic dressings developed in this study modulate cell behavior and facilitate wound healing. Consequently, this research offers a novel approach for the advancement of regenerative wound dressings.


Asunto(s)
Diabetes Mellitus , Plasma Rico en Plaquetas , Animales , Hidrogeles/farmacología , Hidrogeles/química , Biomimética , Cicatrización de Heridas , Murinae , Metacrilatos
7.
Mol Breed ; 43(12): 88, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38045561

RESUMEN

The tassel competes with the ear for nutrients and shields the upper leaves, thereby reducing the yield of grain. The tassel branch number (TBN) is a pivotal determinant of tassel size, wherein the reduced TBN has the potential to enhance the transmission of light and reduce the consumption of nutrients, which should ultimately result in increased yield. Consequently, the TBN has emerged as a vital target trait in contemporary breeding programs that focus on compact maize varieties. In this study, QTL-seq technology and advanced population mapping were used to rapidly identify and dissect the major effects of the TBN on QTL. Advanced mapping populations (BC4F2 and BC4F3) were derived from the inbred lines 18-599 (8-11 TBN) and 3237 (0-1 TBN) through phenotypic recurrent selection. First, 13 genomic regions associated with the TBN were detected using quantitative trait locus (QTL)-seq and were located on chromosomes 2 and 5. Subsequently, validated loci within these regions were identified by QTL-seq. Three QTLs for TBN were identified in the BC4F2 populations by traditional QTL mapping, with each QTL explaining the phenotypic variation of 6.13-18.17%. In addition, for the major QTL (qTBN2-2 and qTBN5-1), residual heterozygous lines (RHLs) were developed from the BC4F2 population. These two major QTLs were verified in the RHLs by QTL mapping, with the phenotypic variation explained (PVE) of 21.57% and 30.75%, respectively. Near-isogenic lines (NILs) of qTBN2-2 and qTBN5-1 were constructed. There were significant differences between the NILs in TBN. These results will enhance our understanding of the genetic basis of TBN and provide a solid foundation for the fine-mapping of TBN. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01431-y.

8.
RSC Adv ; 13(32): 22367-22374, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37497090

RESUMEN

Although disrupted redox homeostasis has emerged as a promising approach for tumor therapy, most existing photosensitizers are not able to simultaneously improve the reactive oxygen species level and reduce the glutathione (GSH) level. Therefore, designing photosensitizers that can achieve these two aspects of this goal is still urgent and challenging. In this work, an organic activatable near-infrared (NIR) photosensitizer, CyI-S-diCF3, is developed for GSH depletion-assisted enhanced photodynamic therapy. CyI-S-diCF3, composed of an iodinated heptamethine cyanine skeleton linked with a recognition unit of 3,5-bis(trifluoromethyl)benzenethiol, can specifically react with GSH by nucleophilic substitution, resulting in intracellular GSH depletion and redox imbalance. Moreover, the activated photosensitizer can produce abundant singlet oxygen (1O2) under NIR light irradiation, further heightening the cellular oxidative stress. By this unique nature, CyI-S-diCF3 exhibits excellent toxicity to cancer cells, followed by inducing earlier apoptosis. Thus, our study may propose a new strategy to design an activatable photosensitizer for breaking the redox homeostasis in tumor cells.

9.
Front Pharmacol ; 14: 1124015, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37229248

RESUMEN

Yajieshaba (YJSB), a traditional Dai medicine formula containing botanical drugs, is commonly employed in Yunnan due to its significant therapeutic effects on liver protection. Consequently, to determine the efficacy of YJSB and the mechanism of action of Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) pathway against liver fibrosis. We wanted to see if YJSB could treat CCl4-induced liver fibrosis by regulating the Keap1-Nrf2 signaling pathway. YJSB significantly improved liver function biochemical indices, liver fibrosis quadruple, hydroxyproline (Hyp), and transforming growth factor-ß1 (TGF-ß1) levels. The staining results demonstrated that the degree of liver fibrosis was significantly reduced. YJSB reduced the content of malondialdehyde (MDA) and elevated the content of superoxide dismutase (SOD) in the liver, exhibiting antioxidant effects; meanwhile, it regulated the expression of Keap1-Nrf2 pathway protein, increased the expression of NAD(P)H: Quinone oxidoreductase (NQO1), Heme Oxygenase 1 (HO-1), Glutamate cysteine ligase modifier subunit (GCLM), and Glutamate cysteine ligase catalytic subunit (GCLC) expression in the liver decreased while Nrf2 expression increased. Fluorescence immunoassay studies demonstrated that YJSB promoted the trans-nuclearization of Nrf2. YJSB possesses anti-liver fibrosis pharmacological effects that improve liver function and effectively counteract CCl4-induced liver fibrosis damage. The mechanism of action might be related to the regulation of protein expression of the Keap1-Nrf2 pathway, increasing the ability of the body to resist oxidative stress and reduce oxidative stress injury.

10.
Environ Pollut ; 318: 120891, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36529338

RESUMEN

Ubiquitous polycyclic aromatic hydrocarbons (PAHs) and metals could induce hyperuricemia and oxidative damage individually, while their co-exposure effects on hyperuricemia risk and the potential roles of oxidative damage in these health outcomes remain poorly understood. We conducted a cross-sectional study in 1379 coke oven workers. We evaluated the levels of PAH-metal exposure and oxidative damage by urinary monohydroxy-PAHs, plasma benzo [a]pyrene-7,8-diol-9,10-epoxide-albumin (BPDE-Alb) adducts, urinary metals, urinary 8-iso-prostaglandin-F2α, and urinary 8-hydroxydeoxyguanosine (8-OH-dG). The subjects were classified into cases of hyperuricemia and controls by the levels of blood uric acid. We found that the sum of multiple hydroxyphenanthrene (ΣOH-Phe) was robustly associated with the increase in hyperuricemia risk, while rubidium and strontium had robust protective associations with hyperuricemia risk (Ptrend<0.05). The risk association of ΣOH-Phe was weaker in workers with high levels of rubidium and strontium [P for modifying effect (PME) < 0.030]. The protective association of strontium was more pronounced in workers with higher ΣOH-Phe (PME = 0.014). We also found that 8-OH-dG was a risk factor for hyperuricemia (Ptrend = 0.006) and mediated 10.13% of the elevated hyperuricemia risk associated with ΣOH-Phe. Our findings suggested that individual PAHs and metals, as well as their co-exposure, may influence hyperuricemia risk among coke oven workers, with oxidative DNA damage playing a potential mediating role in their associations.


Asunto(s)
Coque , Hiperuricemia , Exposición Profesional , Hidrocarburos Policíclicos Aromáticos , Humanos , Hidrocarburos Policíclicos Aromáticos/toxicidad , 8-Hidroxi-2'-Desoxicoguanosina , Exposición Profesional/efectos adversos , Exposición Profesional/análisis , Rubidio , Estudios Transversales , Pueblos del Este de Asia , Hiperuricemia/inducido químicamente , Hiperuricemia/epidemiología , Metales , Estroncio , Estrés Oxidativo , Daño del ADN
11.
ACS Appl Mater Interfaces ; 12(21): 23904-23913, 2020 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-32362118

RESUMEN

Recently, benefiting from the merits of small-molecule acceptors (NFAs), polymer solar cells (PSCs) have achieved tremendous advances. From the perspective of the structural characteristics of the π-conjugated acceptor-donor-acceptor (A-D-A) type of organic molecules, the backbone's planarity and the terminal groups and their substituents have strong influences on the performances of the constructed NFAs. Through enlarging the dihedral angle of the conjugated main chain of NFAs, a certain degree of enhancement of photovoltaic parameters has been achieved. To further probe the influences of ending groups on the performances of nonplanar NFAs, we synthesized two new NFAs i-cc23 and i-cc34 with isomerized thiophene-fused ending groups and a twisted π-conjugated main chain. Compared to i-cc23 containing the 2-(6-oxo-5,6-dihydro-4H-cyclopenta[b]thiophen-4-ylidene)malononitrile ending group, the acceptor i-cc34 containing 2-(6-oxo-5,6-dihydro-4H-cyclopenta[c]thiophen-4-ylidene)malononitrile has a relatively higher molar extinction coefficient, bathochromic-shifted absorption spectrum, and deepened energy levels. When mixed with PBDB-T in solar cells, the i-cc23-based device achieved an excellent open-circuit voltage (VOC) of 1.10 V and a moderate power conversion efficiency of 7.34%. Although the VOC of the i-cc34-related device was decreased to 0.96 V, the short-circuit current density and fill factor were improved, giving rise to an enhanced efficiency of 9.51%. Apart from the distinct photovoltaic performances, the two isomer-based devices exhibit a high radiative efficiency of 8 × 10-4, leading to a very small nonradiative loss of 0.19 V. Our results emphasize the importance of the isomerized thiophene-fused ending groups on the performances of nonplanar NFA-based PSCs.

12.
Anal Chem ; 92(7): 5200-5206, 2020 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-32186358

RESUMEN

Measuring the conformations of protein and protein-ligand complexes in solution is critical for investigating protein bioactivities, but their rapid analyses remain as challenging problems. Here, we report the coupling of Taylor dispersion analysis (TDA) with mass spectrometry (MS) for the rapid conformation differentiation of protein and noncovalent protein complex in solution environments. First, a branched capillary design was applied to achieve double band detection for the peak retention time correction in TDA measurements. After ionization, analytes were further detected and distinguished by their mass to charge (m/z) ratios in the consequent MS analysis. As a result, protein or protein complex in a mixture could be analyzed in terms of both hydrodynamic radius and m/z. The feasibility of this method was verified by analyzing a mixture of angiotensin II and phenylalanine, and the conformations of cytochrome C at different pH conditions were then investigated. As proof-of-concept demonstrations, the complexes of tri-N-acetylchitotriose with two proteins (lysozyme and cytochrome C) were characterized with results verified by molecular dynamics simulations. The TDA-MS method is promising for rapid structural analyses of trace amounts protein-ligand complexes, which could potentially be used to differentiate intact protein or protein complex conformations.


Asunto(s)
Proteínas/química , Teoría Funcional de la Densidad , Espectrometría de Masas , Simulación de Dinámica Molecular , Conformación Proteica
13.
Chem Sci ; 11(18): 4758-4765, 2020 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-34122932

RESUMEN

Established high-throughput proteomics methods provide limited information on the stereostructures of proteins. Traditional technologies for protein structure determination typically require laborious steps and cannot be performed in a high-throughput fashion. Here, we report a new medium throughput method by combining mobility capillary electrophoresis (MCE) and native mass spectrometry (MS) for the 3-dimensional (3D) shape determination of globular proteins in the liquid phase, which provides both the geometric structure and molecular mass information of proteins. A theory was established to correlate the ion hydrodynamic radius and charge state distribution in the native mass spectrum with protein geometrical parameters, through which a low-resolution structure (shape) of the protein could be determined. Our test data of 11 different globular proteins showed that this approach allows us to determine the shapes of individual proteins, protein complexes and proteins in a mixture, and to monitor protein conformational changes. Besides providing complementary protein structure information and having mixture analysis capability, this MCE and native MS based method is fast in speed and low in sample consumption, making it potentially applicable in top-down proteomics and structural biology for intact globular protein or protein complex analysis.

14.
ACS Appl Mater Interfaces ; 12(1): 789-797, 2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-31801347

RESUMEN

Recently, main-chain twisted small molecules are attractive as electron-acceptors in polymer solar cells (PSCs) for their upshifted molecular energy levels, enhanced extinction coefficients, and better charge extraction properties along with longer carrier lifetimes and lower recombination rates relative to their planar analogues, which are conducive to the power conversion efficiency (PCE) promotion of PSCs. To further probe the "structure-performance" correlation of main-chain twisted acceptors, in particular the monofluorine-substituted sites on the performances of the resultant acceptors, two new main-chain twisted small molecules were synthesized, in which a fluorine atom was introduced at different sites on the end-capping group 2-(3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (INCN). Although fine structural modification was adopted, quite different performances were obtained for the two acceptors. Compared to the 3-fluorinated analogue (i-IEICO-F3), a mixture of 4-fluorinated and 5-fluorinated isomers (i-IEICO-2F) exhibited a higher dipole moment, enlarged molar extinction coefficient with a bathochromic-shifted absorption region, suppressed charge recombinations with balanced charge mobilities, and slightly enhanced crystallinity. In combination with a fluorobenzotriazole-based medium-band gap polymer (J52), a high efficiency of 12.86% was resultantly achieved in an i-IEICO-2F-based device, which is superior to the result (7.65%) of the i-IEICO-F3 device, revealing the importance of monofluorinated positions on the performances of main-chain twisted non-fullerene acceptors.

15.
Chem Sci ; 10(33): 7779-7787, 2019 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-31588326

RESUMEN

Measuring the conformations and effective charges of proteins in solution is critical for investigating protein bioactivity, but their rapid analysis remains a challenging problem. Here we report a mobility capillary electrophoresis (MCE) based method for the rapid analysis of protein stereo-structures and effective charges in different solution environments. With the capability of mixture separation, MCE measures the hydrodynamic radius of a protein through Taylor dispersion analysis and its effective charge through ion mobility analysis. The experimental results acquired from MCE are then utilized to restrain molecular dynamics simulations, so that the most probable conformation of that protein can be obtained. As proof-of-concept demonstrations, the charge states and structures of five proteins were analyzed under close to native environments. The conformation transitions and charge state variations of bovine serum albumin and lysozyme under different pH conditions were also investigated. This method is promising for high-throughput protein analysis, which could potentially be coupled with mass spectrometry for investigating protein stereo-structures and functions in top-down proteomics.

16.
ACS Omega ; 4(1): 2377-2386, 2019 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-31459477

RESUMEN

The 3D structures of biomolecules determine their biological function. Established methods in biomolecule structure determination typically require purification, crystallization, or modification of target molecules, which limits their applications for analyzing trace amounts of biomolecules in complex matrices. Here, we developed instruments and methods of mobility capillary electrophoresis (MCE) and its coupling with MS for the 3D structural analysis of biomolecules in the liquid phase. Biomolecules in complex matrices could be separated by MCE and sequentially detected by MS. The effective radius and the aspect ratio of each separated biomolecule were simultaneously determined through the separation by MCE, which were then used as restraints in determining biomolecule conformations through modeling. Feasibility of this method was verified by analyzing a mixture of somatostatin and bradykinin, two peptides with known liquid-phase structures. Proteins could also be structurally analyzed using this method, which was demonstrated for lysozyme. The combination of MCE and MS for complex sample analysis was also demonstrated. MCE and MCE-MS would allow us to analyze trace amounts of biomolecules in complex matrices, which has the potential to be an alternative and powerful biomolecule structure analysis technique.

17.
Sensors (Basel) ; 19(12)2019 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-31207984

RESUMEN

Due to the flexible and compact structures, spherical joints are widely used in parallel manipulators and industrial robots. Real-time detection of the clearance between the ball and the socket in spherical joints is beneficial to compensate motion errors of mechanical systems and improve their transmission accuracy. This work proposes an improved capacitive sensor for detecting the micro-clearance of spherical joints. First, the structure of the capacitive sensor is proposed. Then, the mathematical model for the differential capacitance of the sensor and the eccentric micro-displacement of the ball is deduced. Finally, the capacitance values of the capacitive sensor are simulated with Ansoft Maxwell. The simulated values of the differential capacitances at different eccentric displacements agree well with the theoretical ones, indicating the feasibility of the proposed detection method. In addition, the simulated results show that the proposed capacitive sensor could effectively reduce the capacitive fringe effect, improving the measurement accuracy.

18.
ACS Appl Mater Interfaces ; 11(18): 16795-16803, 2019 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-30987422

RESUMEN

A new main-chain twisted small molecular acceptor with nonhalogenated end groups (i-IEICO) is designed and synthesized. In contrast to its planar analogue IECIO, i-IEICO possesses an obviously twisted backbone, leading to significant hypsochromic shift in film absorption, slight enhancement in solution extinction coefficient, and significantly elevated molecular energy level. Benefited from these features, i-IEICO is matched well with two wide band gap polymer donor materials (J52 and PBDB-T) both in absorption spectra and molecular energy levels. Relative to the planar-molecule IEICO-based devices, the open-circuit voltage ( VOC), short-circuit current density, and fill factor of the i-IEICO-based devices are simultaneously improved, giving rising to a 10.48% (with J52) and 8.79% (with PBDB-T) power conversion efficiency, respectively. Moreover, J52:i-IEICO device exhibits a high VOC of 0.96 V accompanied by a small energy loss of 0.64 eV, which can be further improved to 1.01 V and 0.59 eV for the PBDB-T-based device. The obtained VOC of i-IEICO-based devices are among one of the highest values of either J52 or PBDB-T-based binary devices, suggesting the effectiveness of main-chain twisted strategy coupled with end-group modification to achieve highly efficient nonfullerene acceptors with low energy loss and high VOC.

19.
J Phys Chem B ; 123(10): 2335-2341, 2019 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-30807169

RESUMEN

Protein stereostructure analysis in mixtures still remains challenging, especially large-scale analysis such as in proteomics. With the capability of measuring the hydrodynamic radius of ions in the liquid phase, mobility capillary electrophoresis (MCE) has been applied to study the structure of peptides. In this study, MCE was extended for protein mixture separation and their corresponding hydrodynamic radius analyses. After ellipsoid approximation, the results obtained by MCE experiments were then used as a restraint in molecular dynamics simulations to predict the most probable structure of each protein. Besides a three-protein mixture, a mixture of disulfide bond reduced insulin was also studied by this MCE-restrained modeling method. The results obtained by this method agree with literature studies, and mass spectrometry experiments were also carried out to confirm our findings.


Asunto(s)
Modelos Químicos , Péptidos/química , Proteínas/química , Proteómica/métodos , Electroforesis Capilar , Espectrometría de Masas , Simulación de Dinámica Molecular , Conformación Proteica , Proteómica/instrumentación , Espectrometría de Masa por Ionización de Electrospray , Estereoisomerismo
20.
J Sep Sci ; 37(18): 2513-22, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24975485

RESUMEN

Meconopsis horridula Hook.f. Thoms has been used as a traditional Tibetan medicine to clear away heat, relieve pain, and mobilize static blood. In this study, a reliable method based on high-performance liquid chromatography with diode array detection and electrospray ionization quadrupole time-of-flight tandem mass spectrometry was established for the identification of components in this herb. A total of 40 compounds (including 17 flavonoids, 15 alkaloids, and eight phenylpropanoids) were identified or tentatively identified. Among them, 17 components were identified in the herb for the first time. Compound 39 appears to be a novel compound, which is confirmed as 3-(kaempferol-8-yl)-2,3-epoxyflavanone by NMR spectroscopy and mass spectrometry. Moreover, seven major constituents were simultaneously quantified by the developed high-performance liquid chromatography with tandem triple-quadrupole mass spectrometry method. The quantitative method was validated and quality parameters were established. The study provides a comprehensive approach for understanding this herbal medicine.


Asunto(s)
Alcaloides/análisis , Flavonoides/análisis , Papaveraceae/química , Fenilpropionatos/análisis , Cromatografía Líquida de Alta Presión , Estructura Molecular , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem , Factores de Tiempo
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