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1.
Angew Chem Int Ed Engl ; : e202402497, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38679571

RESUMO

The large size of K-ion makes the pursuit of stable high-capacity anodes for K-ion batteries (KIBs) a formidable challenge, particularly for high temperature KIBs as the electrode instability becomes more aggravated with temperature climbing. Herein, we demonstrate that a hollow ZnS@C nanocomposite (h-ZnS@C) with a precise shell modulation can resist electrode disintegration to enable stable high-capacity potassium storage at room and high temperature. Based on a model electrode, we identify an interesting structure-function correlation of the h-ZnS@C: with an increase in the shell thickness, the cyclability increases while the rate and capacity decreases, shedding light on the design of high-performance h-ZnS@C anodes via engineering the shell thickness. Typically, the h-ZnS@C anode with a shell thickness of 60 nm can deliver an impressive comprehensive performance at room temperature; the h-ZnS@C with shell thickness increasing to 75 nm can achieve an extraordinary stability (88.6% capacity retention over 450 cycles) with a high capacity (450 mAh g-1) and a superb rate even at an extreme temperature of 60 ℃, which is much superior than those reported anodes. This contribution envisions new perspectives on rational design of functional metal sulfides composite toward high-performance KIBs with insights into the significant structure-function correlation.

2.
Plant Cell Environ ; 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38679901

RESUMO

Plant JASMONATE ZIM-DOMAIN (JAZ) genes play crucial roles in regulating the biosynthesis of specialized metabolites and stressful responses. However, understanding of JAZs controlling these biological processes lags due to numerous JAZ copies. Here, we found that two leaf-specific CwJAZ4/9 genes from Curcuma wenyujin are strongly induced by methyl-jasmonate (MeJA) and negatively correlated with terpenoid biosynthesis. Yeast two-hybrid, luciferase complementation imaging and in vitro pull-down assays confirmed that CwJAZ4/9 proteins interact with CwMYC2 to form the CwJAZ4/9-CwMYC2 regulatory cascade. Furthermore, transgenic hairy roots showed that CwJAZ4/9 acts as repressors of MeJA-induced terpenoid biosynthesis by inhibiting the terpenoid pathway and jasmonate response, thus reducing terpenoid accumulation. In addition, we revealed that CwJAZ4/9 decreases salt sensitivity and sustains the growth of hairy roots under salt stress by suppressing the salt-mediated jasmonate responses. Transcriptome analysis for MeJA-mediated transgenic hairy root lines further confirmed that CwJAZ4/9 negatively regulates the terpenoid pathway genes and massively alters the expression of genes related to salt stress signaling and responses, and crosstalks of multiple phytohormones. Altogether, our results establish a genetic framework to understand how CwJAZ4/9 inhibits terpenoid biosynthesis and confers salt tolerance, which provides a potential strategy for producing high-value pharmaceutical terpenoids and improving resistant C. wenyujin varieties by a genetic approach.

3.
Int J Biol Macromol ; 226: 1360-1373, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36442554

RESUMO

Plant-derived monoterpene indole alkaloids (MIAs) from Uncaria rhynchophylla (UR) have huge medicinal properties in treating Alzheimer's disease, Parkinson's disease, and depression. Although many bioactive UR-MIA products have been isolated as drugs, their biosynthetic pathway remains largely unexplored. In this study, untargeted metabolome identified 79 MIA features in UR tissues (leaf, branch stem, hook stem, and stem), of which 30 MIAs were differentially accumulated among different tissues. Short time series expression analysis captured 58 pathway genes and 12 hub regulators responsible for UR-MIA biosynthesis and regulation, which were strong links with main UR-MIA features. Coexpression networks further pointed to two strictosidine synthases (UrSTR1/5) that were coregulated with multiple MIA-related genes and highly correlated with UR-MIA features (r > 0.7, P < 0.005). Both UrSTR1/5 catalyzed the formation of strictosidine with tryptamine and secologanin as substrates, highlighting the importance of key residues (UrSTR1: Glu309, Tyr155; UrSTR5: Glu295, Tyr141). Further, overexpression of UrSTR1/5 in UR hairy roots constitutively increased the biosynthesis of bioactive UR-MIAs (rhynchophylline, isorhynchophylline, corynoxeine, etc), whereas RNAi of UrSTR1/5 significantly decreased UR-MIA biosynthesis. Collectively, our work not only provides candidates for reconstituting the biosynthesis of bioactive UR-MIAs in heterologous hosts but also highlights a powerful strategy for mining natural product biosynthesis in medicinal plants.


Assuntos
Alcaloides , Alcaloides de Vinca , Monoterpenos/metabolismo , Alcaloides Indólicos/metabolismo , Alcaloides de Vinca/química , Alcaloides de Vinca/metabolismo
4.
JBI Evid Implement ; 19(2): 198-207, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32815858

RESUMO

BACKGROUND: Enteral nutrition is commonly used in patients with gastric cancer after a partial or full gastrectomy since it is safe to use and nutrient delivery is in line with human physiological characteristics. However, enteral feeding often leads to deficiency, when the actual intake of the patient is lower than the target demand, which seriously affects the recovery of patients. OBJECTIVE: To implement the best practice for preventing and managing underfeeding during enteral nutrition, and to improve the nutritional status of patients with gastric cancer. METHODS: The current study was conducted following the Joanna Briggs Institute Practical Application of Clinical Evidence System program. Phase one referred to the development of the project, consisting of the generation of the best evidence, mainly based on literature review and discussions within a panel of experts. Phase two was the implementation of the project, including baseline audit, training of enteral nutrition and change of clinical practice. Phase three was a postimplementation reaudit. The intake of enteral nutrition was observed in the first 3 days, and feeding intolerance of enteral nutrition was observed within the first week of enteral nutrition. Data were collected using self-designed questionnaires. The nutritional status of patients was measured using Patient-Generated Subjective Global Assessment (PG-SGA) at admission, and 1 week after surgery. RESULTS: A total of 60 patients with gastric cancer and 10 registered nurses were enrolled in this study. The compliance rate for all audit criteria increased postimplementation. The feeding rate of enteral nutrition postimplementation was higher than the baseline audit on the third day, 54.29% (±12.01) vs. 42.89% (±10.63), and the incidence of underfeeding was lower (30%, n = 30) than the baseline audit (76.67%, n = 30). Furthermore, the feeding intolerance postimplementation (26.67%, n = 30) was lower than the baseline audit (76.67%, n = 30) within 1 week of enteral nutrition. The PG-SGA scores were not significantly different between the baseline audit and postimplementation on the day of admission, while the scores were lower postimplementation (12.90 ±â€Š1.47) compared with the baseline audit (14.00 ±â€Š1.82). CONCLUSION: In this study, we performed an audit of the clinical nursing quality, which can guide nurses to accurately identify obstacles to the implementation of enteral nutrition, and standardize the implementation and management process, thereby improving the quality of nursing and the nutritional status of patients. RELEVANCE TO CLINICAL PRACTICE: The evidence-based practice might optimize the enteral nutrition process, enhance the efficacy of enteral nutrition, and improve the nutritional status of patients. Medical staff should develop an individualized nutritional support protocol for patients based on the results of nutritional status assessments.


Assuntos
Nutrição Enteral/métodos , Gastrectomia , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Nutrição Enteral/efeitos adversos , Prática Clínica Baseada em Evidências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros , Avaliação Nutricional , Estado Nutricional , Cuidados Pós-Operatórios
5.
Research (Wash D C) ; 2019: 5178573, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31912039

RESUMO

Xylitol is one of the most famous chemicals known to people as the essential ingredient of chewing gum and as the sugar alternative for diabetics. Catalytic hydrogenation of biomass-derived xylose with H2 to produce high-value xylitol has been carried out under harsh reaction conditions. Herein, we exhibit the combination of Ru NPs with an environmentally benign MOF (ZIF-67) to afford a heterogeneous composite catalyst. Complete conversion of xylose with 100% selectivity to xylitol was achieved at 50°C and 1 atm H2. This is the first successful attempt to produce xylitol with ambient pressure H2 as well as the first time to achieve a 100% selectivity of xylitol for applicable catalysts. We also proved the universality of the Ru@ZIF-67 towards other hydrogenation processes. Under 1 atm H2, we achieved 100% conversion and >99% selectivity of 1-phenylethanol at 50°C for the hydrogenation of acetophenone. This is also the first report of hydrogenating acetophenone to 1-phenylethanol under 1 atm H2, which confirms that our result not only contributes to enhance the industrial yields of xylitol and reduces both the economical and energy costs but also provides new perspectives on the other hydrogenation process with H2.

6.
Dalton Trans ; 47(6): 1768-1771, 2018 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-29337323

RESUMO

The Co(ii) metal-organic framework (MOF) {[Co(µ3-L)(H2O)]·0.5H2O}n (1, H2L = thiazolidine 2,4-dicarboxylic acid) with rich Lewis acid sites was used as a catalyst for the conversion of CO2 and propylene oxide into propylene carbonate with a yield of up to 98% under 50 °C and 1 atm. 1 exhibited excellent reusability, which could be regenerated easily for at least five runs without a decrease in the yield. Importantly, we synthesized two types of nano-crystals (N1 and N2) of 1 with polyvinylpyrrolidone (PVP) and hexadecyltrimethylammonium bromide (CTAB) as surfactants, respectively, and investigated their catalytic properties in comparison with that of 1 in the powder phase. A significant enhancement in both catalytic efficiency and product yield was observed when 1 was nano-crystallized. This is the first investigation about the relationship between the morphology and the catalytic parameters of MOFs. The results showed a strategy for efficiently applying MOFs as catalysts towards CO2 conversion, which could also be used in other MOF-catalyzed processes.

7.
Inorg Chem ; 56(6): 3414-3420, 2017 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-28263612

RESUMO

The materials Ag@MIL-100(Fe) and Ag@UIO-66(Zr) are obtained for the capture and transformation of CO2 into alkynyl carboxylic acids, which are environmental friendly, facile to synthesize, and exhibit excellent efficiency and reusability. The influence on the catalytic activity of such Ag@MOF systems by metal-organic frameworks' (MOFs) surface area, thermal, and chemical stability, especially the acid-base characteristics of the pores, are compared and discussed systematically.

8.
AORN J ; 105(4): 355-364, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28336024

RESUMO

The self-management of acute postoperative pain is not well researched. This cross-sectional study investigates postoperative pain and pain self-management behavior. We recruited 127 patients who underwent total knee or total hip arthroplasty in an acute care hospital. We measured postoperative pain intensity and pain self-management behavior for three postoperative days. The results showed that the participants experienced mild and moderate pain intensity and perceived moderate to severe pain interference, which influenced their mood, sleep patterns, ability to walk, and performance of general activities and rehabilitation exercises. Female participants reported significantly higher pain intensity and lower pain self-management behavior; highly educated participants reported significantly lower pain intensity and higher self-management behavior. Pain intensity scores had a significant negative correlation with the total self-management behavior score (r = -0.719, P < .01). Health care professionals must consider patients' demographic characteristics when providing education and support regarding pain self-management for postoperative pain control.


Assuntos
Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Dor Pós-Operatória/terapia , Autocuidado , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/diagnóstico , Fatores Sexuais
9.
Biosens Bioelectron ; 48: 210-5, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23685561

RESUMO

This paper describes the synthesis and characterization of a novel electrochemical label for sensitive electrochemical stripping detection of DNA hybridization based on dendrimer-encapsulated copper. The generation 4.5 (G 4.5) carboxyl-terminated poly(amidoamine) dendrimer with a trimesyl core was used as a template for synthesis of Cu²âº/dendrimer nanocomposites (Cu-DNCs). Ratios of Cu²âº/dendrimer were optimized in order to obtain stable nanocomposites with maximal copper loading in the interior of a polymeric shell. Cu-DNCs labeled DNA probe was employed for determining a target ssDNA immobilized on multi-walled carbon nanotubes-modified glassy carbon electrode (GCE) based on a specific hybridization reaction. The hybridization events were monitored by electrochemical detection of Cu anchored on the hybrids after the release in a diluted nitric acid by anodic stripping differential pulse voltammetry (ASDPV). The results showed that only a complementary sequence could form a dsDNA with the Cu-DNCs DNA probe and give an obvious electrochemical signal. The non-complementary sequence exhibited negligible signal change compared with the blank measurement (means: the electrode containing no target DNA incubating in hybridization buffer solution containing Cu-DNCs DNA probe for a certain time). The use of Cu encapsulated-dendrimer as tags and ASDPV for the detection of the released Cu ions could enhance the hybridization signal, and result in the increase of the sensitivity for the target DNA. Under the conditions employed here, the detection limit for measuring the full complementary sequence is down to pM level.


Assuntos
Cobre/química , DNA/análise , Dendrímeros/química , Hibridização de Ácido Nucleico/métodos , Oligonucleotídeos/química , Sondas de DNA/química , Técnicas Eletroquímicas/métodos , Eletrodos , Limite de Detecção , Reprodutibilidade dos Testes
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