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1.
Angew Chem Int Ed Engl ; 63(21): e202401576, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38546410

RESUMEN

The generation of solid electrolyte interphase (SEI) largely determines the comprehensive performance of all-solid-state batteries. Herein, a novel "carrier-catalytic" integrated design is strategically exploited to in situ construct a stable LiF-LiBr rich SEI by improving the electron transfer kinetics to accelerate the bond-breaking dynamics. Specifically, the high electron transport capacity of Br-TPOM skeleton increases the polarity of C-Br, thus promoting the generation of LiBr. Then, the enhancement of electron transfer kinetics further promotes the fracture of C-F from TFSI- to form LiF. Finally, the stable and homogeneous artificial-SEI with enriched lithium dihalide is constructed through the in situ co-growth mechanism of LiF and LiBr, which facilitatse the Li-ion transport kinetics and regulates the lithium deposition behavior. Impressively, the PEO-Br-TPOM paired with LiFePO4 delivers ultra-long cycling stability over 1000 cycles with 81 % capacity retention at 1 C while the pouch cells possess 88 % superior capacity retention after 550 cycles with initial discharge capacity of 145 mAh g-1at 0.2 C in the absence of external pressure. Even under stringent conditions, the practical pouch cells possess the practical capacity with stable electric quantities plateau in 30 cycles demonstrates its application potential in energy storage field.

2.
Angew Chem Int Ed Engl ; 62(39): e202308738, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37528636

RESUMEN

Lithium fluoride (LiF) at the solid electrolyte interface (SEI) contributes to the stable operation of polymer-based solid-state lithium metal batteries. Currently, most of the methods for constructing lithium fluoride SEI are based on the design of polar groups of fillers. However, the mechanism behind how steric hindrance of fillers impacts LiF formation remains unclear. This study synthesizes three kinds of porous polyacetal amides (PAN-X, X=NH2 , NH-CH3 , N-(CH3 )2 ) with varying steric hindrances by regulating the number of methyl substitutions of nitrogen atoms on the reaction monomer, which are incorporated into polymer composite solid electrolytes, to investigate the regulation mechanism of steric hindrance on the content of lithium fluoride in SEI. The results show that bis(trifluoromethanesulfonyl)imide (TFSI- ) will compete for the charge without steric effect, while excessive steric hindrance hinders the interaction between TFSI- and polar groups, reducing charge acquisition. Only when one hydrogen atom on the amino group is replaced by a methyl group, steric hindrance from the methyl group prevents TFSI- from capturing charge in that direction, thereby facilitating the transfer of charge from the polar group to a separate TFSI- and promoting maximum LiF formation. This work provides a novel perspective on constructing LiF-rich SEI.

3.
Hortic Res ; 8(1): 10, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33384411

RESUMEN

Water-soluble phenolic acids are major bioactive compounds in the medicinal plant species Salvia miltiorrhiza. Phenolic acid biosynthesis is induced by methyl jasmonate (MeJA) in this important Chinese herb. Here, we investigated the mechanism underlying this induction by analyzing a transcriptome library of S. miltiorrhiza in response to MeJA. Global transcriptome analysis identified the MeJA-responsive R2R3-MYB transcription factor-encoding gene SmMYB1. Overexpressing SmMYB1 significantly promoted phenolic acid accumulation and upregulated the expression of genes encoding key enzymes in the phenolic acid biosynthesis pathway, including cytochrome P450-dependent monooxygenase (CYP98A14). Dual-luciferase (dual-LUC) assays and/or an electrophoretic mobility shift assays (EMSAs) indicated that SmMYB1 activated the expression of CYP98A14, as well as the expression of genes encoding anthocyanin biosynthesis pathway enzymes, including chalcone isomerase (CHI) and anthocyanidin synthase (ANS). In addition, SmMYB1 was shown to interact with SmMYC2 to additively promote CYP98A14 expression compared to the action of SmMYB1 alone. Taken together, these results demonstrate that SmMYB1 is an activator that improves the accumulation of phenolic acids and anthocyanins in S. miltiorrhiza. These findings lay the foundation for in-depth studies of the molecular mechanism underlying MeJA-mediated phenolic acid biosynthesis and for the metabolic engineering of bioactive ingredients in S. miltiorrhiza.

4.
J Integr Plant Biol ; 62(11): 1688-1702, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32343491

RESUMEN

MYB transcription factors play vital roles in plant growth and metabolism. The phytohormone methyl jasmonate (MeJA) promotes phenolic acid accumulation in the medicinal herb Salvia miltiorrhiza, but the regulatory mechanism is poorly understood. Here, we identified the MeJA-responsive R2R3-MYB transcription factor gene SmMYB2 from a transcriptome library produced from MeJA-treated S. miltiorrhiza hairy roots. SmMYB2 expression was tightly correlated with the expression of key salvianolic acid biosynthetic genes including CYP98A14. SmMYB2 was highly expressed in the periderm of S. miltiorrhiza and SmMYB2 localized to the nucleus. Overexpressing SmMYB2 in S. miltiorrhiza hairy roots significantly increased the levels of salvianolic acids (including rosmarinic acid and salvianolic acid B) by upregulating salvianolic acid biosynthetic genes such as CYP98A14. SmMYB2 binds to the MYB-binding motifs in the promoter of CYP98A14, as confirmed by a dual-luciferase assay and electrophoretic mobility shift assays. Anthocyanin contents were significantly higher in SmMYB2-overexpressing hairy root lines than the control, primarily due to the increased expression of CHI, DFR, and ANS. These findings reveal the novel regulatory role of SmMYB2 in MeJA-mediated phenolic acid biosynthesis, providing a useful target gene for metabolic engineering and shedding light on the salvianolic acid regulatory network.


Asunto(s)
Alquenos/metabolismo , Proteínas de Plantas/metabolismo , Plantas Medicinales/metabolismo , Polifenoles/metabolismo , Salvia miltiorrhiza/metabolismo , Regulación de la Expresión Génica de las Plantas
5.
Crit Rev Food Sci Nutr ; 59(6): 953-964, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29746788

RESUMEN

Salvia miltiorrhiza (Danshen in Chinese), is a well-known traditional Chinese medicinal plant, which is used as not only human medicine but also health-promotion food. Danshen has been extensively used for the treatment of various cardiovascular and cerebrovascular diseases. As a major group of bioactive constituents from S. miltiorrhiza, water-soluble phenolic acids such as salvianolic acid B possessed good bioactivities including antioxidant, anti-inflammatory, anti-cancer and other health-promoting activities. It is of significance to improve the production of phenolic acids by modern biotechnology approaches to meet the increasing market demand. Significant progresses have been made in understanding the biosynthetic pathway and regulation mechanism of phenolic acids in S.miltiorrhiza, which will facilitate the process of targeted metabolic engineering or synthetic biology. Furthermore, multiple biotechnology methods such as in vitro culture, elicitation, hairy roots, endophytic fungi and bioreactors have been also used to obtain pharmaceutically active phenolic acids from S. miltiorrhiza. In this review, recent advances in bioactivities, biosynthetic pathway and biotechnological production of phenolic acid ingredients were summarized and future prospective was also discussed.


Asunto(s)
Biotecnología , Medicamentos Herbarios Chinos/química , Hidroxibenzoatos/metabolismo , Fitoquímicos/biosíntesis , Salvia miltiorrhiza/química , Antibacterianos/farmacología , Antineoplásicos/farmacología , Antioxidantes , Antivirales/farmacología , Vías Biosintéticas/genética , Técnicas de Cultivo de Célula , Medicamentos Herbarios Chinos/farmacología , Endófitos/metabolismo , Humanos , Hidroxibenzoatos/farmacología , Ingeniería Metabólica , Fitoquímicos/farmacología , Salvia miltiorrhiza/genética , Metabolismo Secundario
6.
Sci Rep ; 7(1): 10554, 2017 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-28874707

RESUMEN

Tanshinones and phenolic acids are crucial bioactive compounds biosynthesized in Salvia miltiorrhiza. Methyl jasmonate (MeJA) is an effective elicitor to enhance the production of phenolic acids and tanshinones simultaneously, while yeast extract (YE) is used as a biotic elicitor that only induce tanshinones accumulation. However, little was known about the different molecular mechanism. To identify the downstream and regulatory genes involved in tanshinone and phenolic acid biosynthesis, we conducted comprehensive transcriptome profiling of S. miltiorrhiza hairy roots treated with either MeJA or YE. Total 55588 unigenes were assembled from about 1.72 billion clean reads, of which 42458 unigenes (76.4%) were successfully annotated. The expression patterns of 19 selected genes in the significantly upregulated unigenes were verified by quantitative real-time PCR. The candidate downstream genes and other cytochrome P450s involved in the late steps of tanshinone and phenolic acid biosynthesis pathways were screened from the RNA-seq dataset based on co-expression pattern analysis with specific biosynthetic genes. Additionally, 375 transcription factors were identified to exhibit a significant up-regulated expression pattern in response to induction. This study can provide us a valuable gene resource for elucidating the molecular mechanism of tanshinones and phenolic acids biosynthesis in hairy roots of S. miltiorrhiza.


Asunto(s)
Abietanos/biosíntesis , Hidroxibenzoatos/metabolismo , Salvia miltiorrhiza/genética , Transcriptoma , Abietanos/genética , Genes de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Salvia miltiorrhiza/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
7.
Oncol Lett ; 10(3): 1477-1480, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26622694

RESUMEN

The aim of the present study was to investigate the mutational status of exons 1 and 2 of the p16 gene in the exhaled breath condensate (EBC) of patients with non-small-cell lung cancer (NSCLC) and determine the feasibility and clinical significance of applying EBC in the diagnosis of NSCLC. Polymerase chain reaction and DNA sequencing were applied to detect exon 1 and 2 alterations of the p16 gene in EBC by comparing 58 samples from NSCLC patients and 30 from healthy controls. Of the 58 EBC samples from NSCLC patients, 54 were successfully tested and 8 cases of mutations were identified, of which 3 were in exon 1 and 5 in exon 2. The mutation rate was 14.81% (8/54). There were no p16 gene mutations in the 30 samples obtained from healthy controls. EBC p16 gene mutations exhibited no statistically significant differences according to gender, smoking history, pathological type, degree of differentiation and presence or absence of lymph node metastasis. The p16 gene mutation rate was proportional to the tumor stage (P<0.05). Therefore, the detection of the p16 gene mutation in EBC may be used as a novel molecular marker to assist in the diagnosis of NSCLC.

8.
Technol Health Care ; 24 Suppl 1: S205-11, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26444802

RESUMEN

Mobile apps provide diverse services and various convenient functions. This study applied the modified technology acceptance model (MTAM) in information systems research to the use of the mobile hospital registration system in Taiwan. The MTAM posits that perceived ease of use and perceived usefulness of technology influence users' attitudes toward using technology. Research studies using MTAM have determined information technology experience as a factor in predicting attitude. The objective of this present study is to test the validity of the MTAM model when it is being applied to the mobile registration system. The data was collected from 501 patients in a Taiwan's medical center. Path analysis results have shown that TAM is an applicable model in examining factors influencing users' attitudes of using the mobile registration system. It can be found that the perceived usefulness and the perceived ease of use are positively associated with users' attitudes toward using the mobile registration system, and they can improve users' attitudes of using it. In addition, the perceived ease of use is positively associated with the perceived usefulness. As for the personal prior experience, the information technology experience is positively associated with perceived usefulness and the perceived ease of use.


Asunto(s)
Citas y Horarios , Actitud hacia los Computadores , Administración Hospitalaria , Aplicaciones Móviles/estadística & datos numéricos , Modelos Psicológicos , Adulto , Escolaridad , Humanos , Persona de Mediana Edad , Percepción , Taiwán
9.
Mol Genet Genomics ; 290(4): 1367-77, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25876163

RESUMEN

Tropane alkaloids (TAs) such as anisodamine, anisodine, hyoscyamine and scopolamine are extensively used in clinical practice as anticholinergic agents. Anisodus acutangulus produces TAs in root tissue, and although several genes involved in scopolamine biosynthesis have been cloned, yet the biosynthetic pathway of TAs remains poorly understood. To further understand TAs biosynthesis mechanism, transcriptome analysis with deep RNA sequencing in A. acutangulus roots was performed in this study; 48 unigenes related to tropane, piperidine and pyridine alkaloid biosynthesis, 145 linked to the distribution of arginine to TAs biosynthesis, and 86 categorized to terpenoid backbone biosynthesis have been identified in pathway enrichment analyses with eukaryotic orthologous groups (KOG) and Kyoto encyclopedia of genes and genomes. Additionally, 82 unigenes annotated as cytochrome P450 family members seemed to be involved in secondary metabolism. Genes encoding littorine mutase/monooxygenase (CYP80F1), diamine oxidase (DAO), alcohol dehydrogenase (ADH) and aromatic amino acid aminotransferase (ArAT) may also play roles in TAs biosynthetic pathways. Furthermore, over 1,000 unigenes were identified as potential transcription factors of WRKY, AP2/ERF, MYB and bHLH families, which would be helpful to understand transcriptional regulation of secondary metabolite biosynthesis. These data enable novel insights into A. acutangulus transcriptome, updating the knowledge of TAs biosynthetic mechanism at molecular level.


Asunto(s)
Alcaloides/biosíntesis , Regulación de la Expresión Génica de las Plantas , Solanaceae/genética , Transcriptoma/genética , Tropanos/metabolismo , Vías Biosintéticas/genética , Sistema Enzimático del Citocromo P-450/clasificación , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Filogenia , Proteínas de Plantas/clasificación , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ARN , Solanaceae/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
10.
Chem Commun (Camb) ; 51(38): 8157-60, 2015 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-25872748

RESUMEN

Fast optimization of mesoporous ternary metal oxide (CuCeZrO(w)) catalysts for n-hexane oxidation is achieved via a newly developed combinatorial approach based on ink-jet printing assisted synthesis and multi-dimensional group testing.

11.
Virol J ; 9: 264, 2012 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-23134633

RESUMEN

BACKGROUND: Four major genotypes of hepatitis E virus (HEV), the causative agent of hepatitis E, have so far been recognized. While genotypes 3 and 4 are both zoonotic, the disease symptoms caused by the latter tend to be more severe. To examine if specific nucleotide/amino acid variations between genotypes 3 and 4 play a role in determining the severity of hepatitis E disease, the complete genome of one swine HEV genotype 4 isolate, SAAS-FX17, was determined and compared with other genotype 4 and genotype 3 genomes to identify putative HEV genotype 4 virulence determinants. RESULTS: A total of 42 conformable nt/aa variations between genotype 3 and 4 HEVs were detected, of which 19 were proposed to be potential disease severity determinants for genotype 4 strains. CONCLUSIONS: One potential determinant was located in each of the 5'-UTR and 3'-UTR, 3 and 12 within ORF1 and ORF2 respectively, and 2 in the junction region.


Asunto(s)
Genoma Viral , Genotipo , Virus de la Hepatitis E/genética , Virus de la Hepatitis E/patogenicidad , Regiones no Traducidas 3' , Regiones no Traducidas 5' , Animales , Secuencia de Bases , Virus de la Hepatitis E/clasificación , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Sistemas de Lectura Abierta , Filogenia , ARN Viral/química , ARN Viral/genética , Alineación de Secuencia , Análisis de Secuencia de ADN , Porcinos , Virulencia
12.
Virol J ; 8: 541, 2011 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-22168371

RESUMEN

BACKGROUND: Hepatitis E virus (HEV) causes acute or fulminant hepatitis in humans and is an important public health concern in many developing countries. China has a high incidence of HEV epidemics, with at least three genotypes (1, 3 and 4) and nine subtypes (1b, 1c, 3b, 4a, 4b, 4d, 4g, 4h and 4i) so far identified. Since genotype 3 and the newly identified subtype 4i have been exclusively limited geographically to Shanghai and its neighboring provinces, the epidemiology of HEV infections within the municipality, a major industrial and commercial center, deserves closer attention. FINDINGS: A total of 65 sequences, 60 located within the HEV SH-SW-zs1 genome [GenBank:EF570133], together with five full-length swine and human HEV genomic sequences, all emanating from Shanghai, were retrieved from GenBank. Consistent with the primary role of genotype 4 in China overall, analysis of the sequences revealed this to have been the dominant genotype (58/65) in Shanghai. Six HEV subtypes (3b, 4a, 4b, 4d, 4h and 4i) were also represented. However, although subtype 4a is the dominant subtype throughout China, subtype 4i (29/65) was the most prevalent subtype among the Shanghai sequences, followed by subtypes 4d (10/65) and 4h (9/65). Subtypes 4h, 4i and 4d were found in both swine and humans, whereas 4b was found only in swine and subtype 4a only in humans. CONCLUSIONS: Six different swine and human HEV subtypes have so far been documented in Shanghai. More molecular epidemiological investigations of HEV in swine, and particularly among the human population, should be undertaken.


Asunto(s)
Virus de la Hepatitis E/genética , Hepatitis E/epidemiología , Epidemiología Molecular , Enfermedades de los Porcinos/epidemiología , Población Urbana , Animales , China/epidemiología , Genotipo , Hepatitis E/genética , Hepatitis E/veterinaria , Hepatitis E/virología , Virus de la Hepatitis E/clasificación , Virus de la Hepatitis E/aislamiento & purificación , Humanos , Filogenia , Prevalencia , Análisis de Secuencia de ADN , Porcinos , Enfermedades de los Porcinos/virología
13.
Langmuir ; 26(20): 15761-78, 2010 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-20849093

RESUMEN

This study examines the transport of surfactant that occurs when an aqueous micellar phase is placed in contact with a clean oil phase in which the surfactant is soluble. Upon contact with oil, surfactant monomer on the aqueous side of the interface adsorbs onto the oil/water interface and subsequently desorbs into the oil and diffuses away from the surface. The depletion of aqueous monomer underneath the interface disturbs the monomer-micelle equilibrium, and aggregates break down to replenish the monomer concentration and accelerate the interfacial transport. The depletion of monomer and micelles drives the diffusive flux of these species toward the surface, and the combined effects of diffusion and aggregate kinetic disassembly, alongside kinetic adsorption and desorption at the interface and diffusion away from the interface into the oil, determine the interfacial transport rate. This interfacial transport is examined here in the quasi-static limit in which the diffusion of monomer and micelles in the aqueous phase is much slower than the time scale for micelle disassembly. In this limit, when the initial bulk concentration of micelles in the aqueous solution is small, the micelle diffusive flux to the surface cannot keep up with the micelle breakdown under the interface, and a micelle-free zone forms. This zone extends from the surface into the aqueous phase up to a boundary that demarcates the beginning of a zone, containing micelles, that extends further into the aqueous phase. Micelles diffuse from the micelle zone to the boundary, where they break down, causing the boundary to retreat. Released monomer diffuses through the micelle-free zone and partitions into the oil phase. The focus of this study is to verify this transport picture by visualizing the micelle-free zone and comparing the movement of the zone to predictions obtained from a transport model based on this two-zone picture. A small hydrophobic dye molecule (Nile red) is incorporated into the micelles; the dye fluoresces only in the hydrophobic environment of the micelles, providing visual contrast between the two zones. Through spatial mapping of the fluorescence using confocal microscopy, the movement of the micelle-free zone boundary can be measured and is shown to compare favorably with simulations of the transport model.

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