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1.
Phys Chem Chem Phys ; 26(17): 13395-13404, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38647031

RESUMEN

Carbonaceous materials are promising candidates as anode materials for non-lithium-ion batteries (NLIBs) due to their appealing properties such as good electrical conductivity, low cost, and high safety. However, graphene, a classic two-dimensional (2D) carbon material, is chemically inert to most metal atoms, hindering its application as an electrode material for metal-ion batteries. Inspired by the unique geometry of a four-penta unit, we explore a metallic 2D carbon allotrope C5-10-16 composed of 5-10-16 carbon rings. The C5-10-16 monolayer is free from any imaginary frequencies in the whole Brillouin zone. Due to the introduction of a non-sp2 hybridization state into C5-10-16, the extended conjugation of π-electrons is disrupted, leading to the enhanced surface activity toward metal ions. We investigate the performance of C5-10-16 as the anode for sodium/potassium-ion batteries by using first-principles calculations. The C5-10-16 sheet has high theoretical specific capacities of Na (850.84 mA h g-1) and K (743.87 mA h g-1). Besides, C5-10-16 exhibits a moderate migration barrier of 0.63 (0.32) eV for Na (K), ensuring rapid charging/discharging processes. The average open-circuit voltages of Na and K are 0.33 and 0.62 V, respectively, which are within the voltage acceptance range of anode materials. The fully sodiated (potassiated) C5-10-16 shows tiny lattice expansions of 1.4% (1.3%), suggesting the good reversibility. Moreover, bilayer C5-10-16 significantly affects both the adsorption strength and the mobility of Na or K. All these results show that C5-10-16 could be used as a promising anode material for NLIBs.

2.
Br J Pharmacol ; 2024 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-38644540

RESUMEN

BACKGROUND AND PURPOSE: White adipose tissue (WAT) is involved in rheumatoid arthritis (RA). This study explored its potential as an antirheumatic target. EXPERIMENTAL APPROACH: WAT status of healthy and adjuvant-induced arthritis (AIA) rats were compared. The contribution of WAT to RA pathology was evaluated by pre-adipocyte transplant experiments and by dissecting perirenal fat pads of AIA rats. The impact of RA on WAT was investigated by culturing pre-adipocytes. Proteins differentially expressed in WAT of healthy and AIA rats were identified by the UPLC/MS2 method. These together with PPARγ siRNA and agonist were used to treat pre-adipocytes in vitro. The medium was used for THP-1 monocyte culture. KEY RESULTS: Compared with healthy controls, AIA WAT was smaller but secreted more leptin, eNAMPT, MCP-1, TNF-α, and IL-6. AIA rat pre-adipocytes increased the levels of these adipokines in healthy recipients. RA patients' serum induced a similar secretion change and impaired differentiation of pre-adipocytes. Adipectomy eased AIA-related immune abnormalities and arthritic manifestations. Hepatokines PON1, IGFBP4, and GPIHBP1 were among the differential proteins in high levels in RA blood, and induced inflammatory secretions by pre-adipocytes. GPIHBP1 inhibited PPARγ expression and caused differentiation impairment and inflammatory secretion by pre-adipocytes, a similar outcome to PPARγ-silencing. This endowed the cells with an ability to activate monocytes, which can be abrogated by rosiglitazone. CONCLUSION AND IMPLICATIONS: Certain hepatokines potentiate inflammatory secretions by pre-adipocytes and expedite RA progression by inhibiting PPARγ. Targeting this signalling or abnormal WAT secretion by various approaches may reduce RA severity.

3.
Phys Chem Chem Phys ; 26(15): 11738-11745, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38563831

RESUMEN

High-performance sodium-ion batteries (SIBs) require anode materials with high capacity and fast kinetics. Based on first-principles calculations, we propose BC3N2 and BC3N2/graphene (B/G) heterostructure as potential SIB anode materials. The BC3N2 monolayer exhibits intrinsic metallic behavior. In addition, BC3N2 possesses a low Na+ diffusion barrier (0.15 eV), a high storage capacity (777 mA h g-1), a low open-circuit voltage (0.72 V), and a tiny axial expansion (0.36%). Compared with the BC3N2 monolayer, the B/G heterostructure exhibits a lower diffusion barrier of 0.027 eV, suggesting a much faster diffusion. More importantly, although the B/G heterostructure possesses heavier molar weight, its theoretical capacity (689 mA h g-1) is comparable to that of the BC3N2 monolayer. Based on the above-mentioned properties, we hope both the BC3N2 monolayer and the B/G heterostructure would be promising anodes for SIBs.

4.
J Phys Chem Lett ; 15(9): 2485-2492, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38408427

RESUMEN

We propose a two-dimensional carbon allotrope (named KT-graphene) by incorporating kagome and tetragonal lattices consisting of trigonal, quadrilateral, octagonal, and dodecagonal rings. The introduction of non-hexagonal rings can give rise to the localized electronic states that improve the chemical reactivity toward potassium, making KT-graphene a high-performance anode material for potassium-ion batteries. It shows a high theoretical capacity (892 mAh g-1), a low diffusion barrier (0.33 eV), and a low average open-circuit voltage (0.51 V). The presence of electrolyte solvents is propitious to boost the K-ion adsorption and diffusion capabilities. Moreover, one-dimensional nanotubes (KT-CNTs), rolled up by the KT-graphene sheet, are metallic regardless of the tube diameter. As the curvature increases, KT-CNTs exhibit significantly increased surface activity, which can promote the electron-donating ability of K. Furthermore, the curvature effect greatly enhances the efficiency of K diffusion on the inner surface compared to that on the outer surface.

5.
Phys Chem Chem Phys ; 26(5): 4589-4596, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38250962

RESUMEN

Multivalent-ion batteries have garnered significant attention due to their high energy density, low cost, and superior safety. Calcium-ion batteries (CIBs) are regarded as the next-generation energy storage systems for their abundant natural resources and bivalent characteristics. However, the absence of high-performance anode materials poses a significant obstacle to the progress of battery technology. Two-dimensional (2D) Dirac materials have excellent conductivity and abundant active sites, rendering them promising candidates as anode materials. A novel 2D Dirac material known as "graphene+" has been theoretically reported, exhibiting prominent properties including good stability, exceptional ductility, and remarkable electronic conductivity. By using first-principles calculations, we systematically investigate the performance of graphene+ as an anode material for CIBs. Graphene+ exhibits an ultra-high theoretical capacity (1487.7 mA h g-1), a small diffusion barrier (0.21 eV), and a low average open-circuit voltage (0.51 V). Furthermore, we investigate the impact of the electrolyte solvation on the performance of Ca-ion adsorption and migration. Upon contact with electrolyte solvents, graphene+ exhibits strong adsorption strength and rapid migration of Ca-ions on its surface. These results demonstrate the promising potential of graphene+ as a high-performance anode material for CIBs.

6.
Phys Chem Chem Phys ; 25(42): 28814-28823, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37850539

RESUMEN

Sodium-ion batteries (SIBs) have attracted much attention due to their abundant earth-reserves and low cost. Two-dimensional (2D) Dirac materials show great application prospects as anodes for SIBs because of their excellent electronic conductivity. We explore the performances of AlB4 (Al2B2) monolayers and bilayers as anodes for SIBs by using first-principles calculations. The AlB4 (Al2B2) monolayer exhibits a high theoretical storage capacity of 954.15 (709.17) mA h g-1 and a low diffusion barrier of 0.36 (0.03) eV. The calculated average open-circuit voltage (0.68/0.18 V) falls within the acceptance range of 0.1-1.0 V for anode materials. The fully sodiated AlB4 (Al2B2) monolayer shows a tiny lattice expansion of 0.9% (2.4%), suggesting good reversibility. Furthermore, in comparison with the AlB4 (Al2B2) monolayer, the AlB4 (Al2B2) bilayer can provide stronger binding with Na on the outside surface. These results contribute to a better understanding of the AlB4 (Al2B2) monolayers and bilayers as potential high-performance anode materials for SIBs.

7.
Phys Chem Chem Phys ; 25(42): 29224-29232, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37873573

RESUMEN

Lithium-ion batteries (LIBs) remain irreplaceable for clean energy storage applications. The intrinsic metallic nature of penta-SiCN ensures its promising application in the electrodes of LIBs. Using first-principles calculations, we evaluate the performance of the intrinsic metallic penta-SiCN monolayer as the anode material for LIBs. Penta-SiCN exhibits a low diffusion energy barrier (0.107 eV) for Li atom migration on Si18C18N18, while the diffusion energy barrier for vacancy migration on Li17Si18C18N18 is only 0.006 eV. Additionally, penta-SiCN possesses a high theoretical capacity of 1485.98 mA h g-1, average open-circuit voltage of 0.97 V, and small volume expansion of 1%. Remarkably, penta-SiCN exhibits robust wettability towards the electrolytes (solvent molecules and metal salts) widely used in commercial LIBs, indicating the excellent compatibility in electrode applications. These intriguing theoretical findings make penta-SiCN a high performance anode material for LIBs.

8.
Phys Chem Chem Phys ; 25(37): 25344-25352, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37703031

RESUMEN

Giant magnetoresistance was first experimentally discovered in three-dimensional magnetic tunnel junctions (MTJs) in the late 1980s and is of great importance in nonvolatile memory applications. How to achieve a magnetoresistance as large as possible is always a central task in the study of MTJs. However, it is normally only of the order of magnitude of tens of percent in traditional MTJs. The ideal situation is the metal-insulator transition together with the magnetization reversal of one magnetic lead. In this work, we will show that this can be achieved using a two-dimensional ferromagnetic zigzag SiC nanoribbon junction based on quantum transport calculations performed with a combination of density functional theory and non-equilibrium Green's function. Specifically, with the magnetization configuration switching of the two leads from parallel to anti-parallel, the junction will change abruptly from a conducting state to an insulating state, although the two leads are always metallic, with both spin up and spin down channels crossing the Fermi level simultaneously. Extensive analysis indicates that the insulating state in the anti-parallel magnetic configuration originates not from any present mechanisms that cause full suppression of electron transmission but from momentum direction mismatching. This finding suggests a fantastic mechanism for achieving magnetoresistance or electrical switching in nanoscale devices by manipulating band dispersion.

9.
Phys Chem Chem Phys ; 25(27): 18158-18165, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37386910

RESUMEN

Ferroelectric tunnel junctions (FTJs) have great potential in nonvolatile memory devices and have been extensively studied in recent years. Compared with conventional FTJs based on perovskite-type oxide materials as the barrier layer, two-dimensional (2D) van der Waals ferroelectric materials are advantageous in improving the performance of FTJs and achieving miniaturization of FTJ devices due to the features such as atomic thickness and ideal interfaces. In this work, we present a 2D out-of-plane ferroelectric tunnel junction (FTJ) constructed using graphene and bilayer-In2Se3. Using density functional calculations combined with the nonequilibrium Green's function technique, we investigate the electron transport properties in the graphene/bilayer-In2Se3 (BIS) vdW FTJ. Our calculations show that the FTJ we constructed can be switched from ferroelectric to antiferroelectric by changing the relative dipole arrangement of the BIS to form multiple nonvolatile resistance states. Since the charge transfer between the layers varies for the four different polarization states, the TER ratios range from 103% to 1010%. The giant tunneling electroresistance and multiple resistance states in the 2D BIS-based FTJ suggest that it has great potential for application in nanoscale nonvolatile ferroelectric memory devices.

10.
Phys Chem Chem Phys ; 25(22): 15295-15301, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37222137

RESUMEN

Two-dimensional (2D) carbon materials integrated with planar tetracoordinate carbon (ptC) and negative Poisson's ratio (NPR) provide a cornerstone for constructing multifunctional energy-storage devices. As a typical 2D carbon material, the pristine graphene is chemically inert, hindering its application in metal-ion batteries. Introducing the ptC in graphene can break the extended conjugation of π-electrons and lead to an enhanced surface reactivity. Inspired by the unique geometry of [4.6.4.6] fenestrane skeleton with ptC, we theoretically design a ptC-containing 2D carbon allotrope, namely THFS-carbon. It is intrinsically metallic with excellent dynamical, thermal, and mechanical stabilities. The Young's modulus along the x direction (311.37 N m-1) is comparable to that of graphene. Intriguingly, THFS-carbon possesses an in-plane half-NPR distinct from most other 2D crystals. As a promising anode for sodium-ion batteries, THFS-carbon delivers an ultra-high theoretical storage capacity (2233 mA h g-1), a low diffusion energy barrier (0.03-0.05 eV), a low open-circuit voltage (0.14-0.40 V), and a good reversibility for Na insertion/extraction.

11.
Phys Chem Chem Phys ; 25(16): 11513-11521, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37039312

RESUMEN

Na-ion batteries (NIBs) have attracted a great deal of attention for large-scale electric energy storage due to their inherent safety, natural abundant resources, and low cost. The exploration of suitable anode materials is the major challenge in advancing NIB technology. On the basis of first-principles calculations, we systematically explore the potential performance of two-dimensional (2D) TiCl2 as an electrode material for NIBs. Monolayer TiCl2 can be easily exfoliated from the bulk structure with a small exfoliation energy of 0.64 J m-2. It shows good stability, as demonstrated by its high cohesive energy, positive phonon modes, and high thermal stability. Monolayer TiCl2 has high storage capacity (451.3 mA h g-1), low diffusion energy barrier (0.02-0.14 eV), moderate average open-circuit voltage (0.81 V), and small lattice change (2.37%). Moreover, bilayer TiCl2 can significantly enhance the Na adsorption strength but reduce the Na-ion diffusion ability. These results suggest that TiCl2 is a promising anode candidate for NIBs.

12.
J Agric Food Chem ; 71(13): 5391-5402, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36971245

RESUMEN

Drought adaptation of plants is closely related to resistance and tolerance to drought stress as well as the ability to recover after the elimination of the stress. Glycyrrhiza uralensis Fisch is a commonly applied herb whose growth and development are greatly affected by drought. Here, we provide the first comprehensive analysis of the transcriptomic, epigenetic, and metabolic responses of G. uralensis to drought stress and rewatering. The hyper-/hypomethylation of genes may lead to up-/downregulated gene expression, and epigenetic changes can be regarded as an important regulatory mechanism of G. uralensis under drought stress and rewatering. Moreover, integrated transcriptome and metabolome analysis revealed that genes and metabolites involved in pathways of antioxidation, osmoregulation, phenylpropanoid biosynthesis, and flavonoid biosynthesis may regulate the drought adaptation of G. uralensis. This work provides crucial insights into the drought adaptation of G. uralensis and offers epigenetic resources for cultivating G. uralensis with high drought adaptation.


Asunto(s)
Glycyrrhiza uralensis , Glycyrrhiza , Glycyrrhiza uralensis/genética , Glycyrrhiza uralensis/metabolismo , Multiómica , Sequías , Antioxidantes/metabolismo , Transcriptoma , Glycyrrhiza/genética
13.
Phys Chem Chem Phys ; 25(8): 6519-6526, 2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36786369

RESUMEN

High specific capacity and fast charge/discharge rate are important indicators for the development of next-generation ion batteries. Compared with conventional monovalent ion batteries like lithium-ion batteries and sodium-ion batteries, multivalent ion batteries have attracted extensive attention owing to their high energy densities. Here, we systematically explore the interactions between Mg atoms and α-beryllene monolayers by means of density functional theory calculations. Mg atoms can be adsorbed stably on α-beryllene monolayers with the adsorption energy of -0.24 eV. The low diffusion energy barriers (0.099/0.101 eV) indicate the rapid mobility of Mg during the charge/discharge process. Moreover, the α-beryllene monolayer exhibits an ultra-high theoretical specific capacity of 5956 mA h g-1 for Mg, a low average open-circuit voltage of 0.24 V, and a tiny volume change of -1.08%. Finally, the constructed h-BN/α-beryllene heterostructure shows that h-BN can serve as a protective cover to preserve pristine α-beryllene in respect of metallicity, Mg adsorption capability, and fast ionic mobility. The above mentioned outstanding results make α-beryllene a promising anode material for magnesium-ion batteries.

14.
Zhongguo Zhong Yao Za Zhi ; 48(24): 6812-6816, 2023 Dec.
Artículo en Chino | MEDLINE | ID: mdl-38212039

RESUMEN

By studying various ancient texts such as herbal classics and medical literature from different eras, it was found that there were discrepancies in the records about Bambusae Concretio Silicea(Tian Zhu Huang). In order to establish an accurate foundation, this research was based on ancient herbal literature and combined with plant morphology and investigative studies to examine its earliest mentions in ancient texts, nomenclature, medicinal properties, indications, and quality assessment standards. In the early records, Bambusae Concretio Silicea was referred to by several different names, such as "Zhu Huang" "Tian Zhu Huang" "Zhu Gao" "Zhu Tang", and "Zhu Huang". The earliest known formal usage of the name "Tian Zhu Huang" was found in the book Ri Hua-zi's Materia Medica(Ri Hua Zi Ben Cao). Throughout various ancient texts, the earliest recorded information about Bambusae Concretio Silicea also appeared in Ri Hua-zi's Materia Medica, not in Materia Medica of Sichuan(Shu Ben Cao) or other ancient texts. Ri Hua-zi's Materia Medica provided relevant descriptions of its origin, medicinal properties, and indications, albeit with some errors due to limited knowledge. However, this has been a valuable starting point for future research on Bambusae Concretio Silicea and holds pioneering significance in forming a mature system. As the research delved deeper, the medicinal properties of Bambusae Concretio Silicea have been consistent since Ri Hua-zi's Materia Medica, and the understanding has gradually improved through years of clinical verification. During the investigation process, the authors found limited records on the quality evaluation of Bambusae Concretio Silicea in ancient texts. Although the information is scarce, it serves as a foundational basis for establishing corresponding quality grading standards for Bambusae Concretio Silicea in the future.


Asunto(s)
Materia Medica , China , Medicina Tradicional China
15.
Zhongguo Zhong Yao Za Zhi ; 47(15): 4055-4065, 2022 Aug.
Artículo en Chino | MEDLINE | ID: mdl-36046895

RESUMEN

The content of total flavonol glycosides in Ginkgo Folium in the planting bases was determined by high performance liquid chromatography(HPLC).The samples were extracted by reflux with methanol-25% hydrochloric acid.The HPLC conditions were as follows: Agilent ZORBAX SB-C_(18) column(4.6 mm×250 mm, 5 µm), isocratic elution with mobile phase of 0.4% phosphoric acid solution-methanol(45∶55), flow rate of 1 mL·min~(-1), column temperature of 30 ℃, detection wavelength of 360 nm, and injection vo-lume of 10 µL.A method for the determination of terpene lactones in Ginkgo Folium was established based on ultra-high performance liquid chromatograph-triple-quadrupole/linear ion-trap tandem mass spectrometry(UPLC-QTRAP-MS/MS).The UPLC conditions were as below: gradient elution with acetonitrile-0.1% formic acid, flow rate of 0.2 mL·min~(-1), column temperature of 30 ℃, sample chamber temperature of 10 ℃, and injection volume of 10 µL.The ESI~+and multiple reaction monitoring(MRM) were adopted for the MS.The above methods were used to determine the content of total flavonol glycosides and terpene lactones in 99 batches of Ginkgo Folium from 6 planting bases, and the results were statistically analyzed.The content of flavonoids and terpene lactones in Ginkgo Folium from different origins, from trees of different ages, harvested at different time, from trees of different genders, and processed with different methods was compared.The results showed that the content of total flavonol glucosides in 99 Ginkgo Folium samples ranged from 0.38% to 2.08%, and the total content of the four terpene lactones was in the range of 0.03%-0.87%.The method established in this study is simple and reliable, which can be used for the quantitative analysis of Ginkgo Folium.The research results lay a basis for the quality control of Ginkgo Folium.


Asunto(s)
Flavonoides , Ginkgo biloba , Cromatografía Líquida de Alta Presión/métodos , Flavonoides/análisis , Flavonoles , Glicósidos/análisis , Lactonas/análisis , Metanol , Hojas de la Planta/química , Espectrometría de Masas en Tándem/métodos , Terpenos/análisis , Árboles
16.
J Phys Condens Matter ; 34(36)2022 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-35767983

RESUMEN

Two-dimensional (2D) materials provide tremendous opportunities for next-generation energy storage technologies. We theoretically propose 2D group-IV oxides (α-, ß-, andγ-CXO, X = Si/Ge). Among them,α-CXO monolayers, composed of the C-O-X skeleton of silyl (germyl) methyl ether molecules, are the most stable phase.α-CXO possess robust dynamical, mechanical, and thermal stabilities. Remarkably,α-CGeO has an unusual negative Poisson's ratio (NPR). However,α-CSiO displays a bidirectional half-auxeticity, different from all the already known NPR behaviors. The intrinsic moderate direct-band-gap, high carrier mobility, and superior optical absorption ofα-CXO make them attractive for optoelectronics applications. A series ofα-CXO-based excitonic solar cells can achieve high power conversion efficiencies. Besides,α-CXO monolayers are promising anode materials for sodium- and potassium-ion batteries, exhibiting not only the high specific capacity (532-1433 mA h g-1) but also low diffusion barrier and open-circuit voltage. In particular, the specific capacity of K onα-CSiO exhibits one of the highest values ever recorded in 2D materials. The multifunctionality rendersα-CXO promising candidates for nanomechanics, nanoelectronics, and nano-optics.

17.
Nanoscale ; 14(16): 6118-6125, 2022 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-35388866

RESUMEN

Sodium-ion batteries (SIBs) have attracted great attention owing to their low cost and inherent safety. High-performance anode materials for SIBs should possess intrinsically metallic characteristic and be composed of non-toxic, earth abundant, and lightweight elements. We predict a two-dimensional Mg material (named magnesene) to be an excellent anode material, which can meet these design requirements. It is demonstrated to be stable in terms of the cohesive energy, phonon spectrum, ab initio molecular dynamics simulation, and elastic constants. The magnesene monolayer exhibits good SIB performances, including a high storage capacity of 551.3 mA h g-1, low diffusion energy barrier (0.16-0.19 eV), low open-circuit voltage (0.71-0.82 V), and small volume change (4.7%). Moreover, graphene or h-BN on top of magnesene could serve as a protective cover to preserve the performances of pristine magnesene, such as metallicity, strong Na adsorption capability, and fast ionic mobility. These intriguing theoretical findings make magnesene a promising anode material for SIBs.

18.
J Agric Food Chem ; 70(13): 4076-4085, 2022 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-35321541

RESUMEN

Quercetin 3-O-N-acetylgalactosamine (Q3GalNAc), a derivative of dietary hyperoside, had never been enzymatically synthesized due to the lack of well-identified N-acetylgalactosamine-transferase (GalNAc-T). Herein, PhUGT, an identified flavonoid 3-O-galactosyltransferase from Petunia hybrida, was demonstrated to display quercetin GalNAc-T activity, transferring a N-acetylgalactosamine (GalNAc) from UDP-N-acetylgalactosamine (UDP-GalNAc) to the 3-OH of quercetin to form Q3GalNAc with a low conversion of 11.7% at 40 °C for 2 h. Protein engineering was thus performed, and the resultant PhUGT variant F368T got an enhanced conversion of 75.5% toward UDP-GalNAc. The enzymatically synthesized Q3GalNAc exhibited a comparable antioxidant activity with other quercetin 3-O-glycosides. Further studies revealed that PhUGT was a donor promiscuous glycosyltransferase (GT), recognizing seven sugar donors. This finding overturned a previous notion that PhUGT exclusively recognized UDP-galactose (UDP-Gal). The reason why PhUGT was mistaken for a UDP-Gal-specific GT was demonstrated to be a shorter reaction time, in which many quercetin 3-O-glycosides, except hyperoside, could not be effectively synthesized. The fact that the microbial cell factory expressing PhUGT could yield an array of Q3Gs further confirmed the donor promiscuity of PhUGT. This study laid a foundation for the scale production of Q3GalNAc and provided a potent biocatalyst capable of glycodiversifying quercetin as well.


Asunto(s)
Acetilgalactosamina , Glicosiltransferasas , Acetilgalactosamina/metabolismo , Antioxidantes , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Ingeniería de Proteínas , Quercetina
19.
Chin Med J (Engl) ; 134(22): 2721-2729, 2021 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-34732665

RESUMEN

BACKGROUND: The chaperonin containing t-complex (CCT) proteins play an important role in cell cycle-related protein degradation in yeast and mammals. The role of the chaperonin containing t-complex 4 (CCT4), one subtype of CCT proteins, in the progress of hepatocellular carcinoma (HCC) was not fully elucidated. Here, we aimed to explore the mechanisms of CCT4 in HCC. METHODS: In this study, we used the UALCAN platform to analyze the relationship between CCT4 and HCC, and the association of CCT4 with the overall survival (OS) of HCC patients was also analyzed. CCT4 expression in HCC tumor tissues and normal tissues was also determined by western blot (WB) assay. Lentivirus vector was used to knock down the CCT4 expression, and quantitative polymerase chain reaction and WB were used to determine the level of CCT4 in HCC cell lines. Cell counting kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) assays were used to detect the cell proliferation, and flow cytometry (FCM) was performed to evaluate the effect of CCT4 on the apoptosis of HCC cells. Co-immunoprecipitation (co-IP) assay and WB were used to explore the mechanisms of CCT4 regulating the growth of HCC. Data were calculated from at least three replicate experiments and expressed as mean ± standard deviation. Student's t test, paired t test, and Kaplan-Meier analysis were used to compare across different groups. RESULTS: We found CCT4 was upregulated in HCC tissues compared with normal tissues, and its high expression was associated with poor prognosis (P < 0.001). CCT4 was significantly increased in HCC tumor tissues compared with normal tissues (0.98 ±â€Š0.12 vs. 0.23 ±â€Š0.05, t = 7.73, P < 0.001). After being transfected with CCT4 short-hairpin RNA (shRNA), CCT4 was decreased in mRNA level and protein level in both Huh7 (mRNA level: 0.41 ±â€Š0.07 vs. 1.01 ±â€Š0.11, t = 8.09, P = 0.001; protein level: 0.61 ±â€Š0.03 vs. 0.93 ±â€Š0.07, t = 7.19, P = 0.002) and Hep3b cells (mRNA level: 0.55 ±â€Š0.11 vs. 1.04 ±â€Š0.15, t = 4.51, P = 0.011; protein level: 0.64 ±â€Š0.10 vs. 0.95 ±â€Š0.08, t = 4.32, P = 0.012). CCK8 assay indicated that CCT4 knockdown inhibited cell proliferation in both Huh7 (OD value of 3 days: 0.60 ±â€Š0.14 vs. 0.97 ±â€Š0.16, t = 3.13, P = 0.036; OD value of 4 days: 1.03 ±â€Š0.07 vs. 1.50 ±â€Š0.12, t = 5.97, P = 0.004) and Hep3b (OD value of 3 days: 0.69 ±â€Š0.14 vs. 1.10 ±â€Š0.11, t = 3.91, P = 0.017; OD value of 4 days: 1.12 ±â€Š0.12 vs. 1.48 ±â€Š0.13, t = 3.55, P = 0.024) cells. EdU assay showed that CCT4 knockdown inhibited the cell proliferation in both Huh7 (EdU positive rate: [31.25 ±â€Š3.41]% vs. [58.72 ±â€Š3.78]%, t = 9.34, P = 0.001) and Hep3b cells (EdU positive rate: [44.13 ±â€Š7.02]% vs. [61.79 ±â€Š3.96]%, t = 3.79, P = 0.019). FCM assay suggested that CCT4 knockdown induced apoptosis in HCC cells (apoptosis rate of Huh7: [9.10 ±â€Š0.80]% vs. [3.66 ±â€Š0.64]%, t = -9.18, P = 0.001; apoptosis rate of Hep3b: [6.69 ±â€Š0.72]% vs. [4.20 ±â€Š0.86]%, t = -3.84, P = 0.018). We also found that CCT4 could regulate anaphase-promoting complex (APC)Cdc20 activity via interacting with Cdc20. Furthermore, CCT4 knockdown induced securin (0.65 ±â€Š0.06 vs. 0.44 ±â€Š0.05, t = -4.69, P = 0.009) and B-cell lymphoma-2 (Bcl-2) interacting mediator of cell death (Bim; 0.96 ±â€Š0.06 vs. 0.61 ±â€Š0.09, t = -5.65, P = 0.005) accumulation. The upregulation of securin inhibited cell growth by downregulating cyclin D1 (0.65 ±â€Š0.05 vs. 1.04 ±â€Š0.07, t = 8.12, P = 0.001), and the accumulation of Bim inhibited Bcl-2 (0.77 ±â€Š0.04 vs. 0.87 ±â€Š0.04, t = 3.00, P = 0.040) and activated caspase 9 (caspase 9: 0.77 ±â€Š0.04 vs. 0.84 ±â€Š0.05, t = 1.81, P = 0.145; cleaved caspase 9: 0.64 ±â€Š0.06 vs. 0.16 ±â€Š0.07, t = 1.81, P = 0.001), which led to elevated apoptosis. CONCLUSIONS: Overall, these results showed that CCT4 played an important role in HCC pathogenesis through, at least partly, interacting with Cdc20.


Asunto(s)
Carcinoma Hepatocelular , Chaperonina con TCP-1/metabolismo , Neoplasias Hepáticas , Apoptosis , Carcinoma Hepatocelular/genética , Proteínas Cdc20 , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/genética
20.
J Phys Condens Matter ; 33(31)2021 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-34132204

RESUMEN

Pristine germanene is a zero-gap semi-metal, which may hinder its practical application in semiconducting devices. Here, on the basis of the structural characteristics of digermyl ether, we theoretically design a two-dimensional crystal, namely germanether. Germanether exhibits excellent dynamical and thermal stability. It possesses an indirect band gap of 1.37 eV and a high electron mobility of 2.32 × 103 cm2 V-1 s-1. The uniaxial strain and layer stacking order can trigger an indirect-to-direct band gap transition. More interestingly, germanether has remarkable in-plane negative Poisson's ratios with the largest one (∼-0.2) five times of borophenes and three times of penta-graphene. The negative Poisson's ratio arises from the interplay of Ge-O tetrahedron symmetry and Ge-4d orbitals involvement, which is different from previously reported auxetic materials. All these findings render germanether is a competitive material for the future application in nanomechanics and nanoelectronics.

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