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1.
Small ; 20(34): e2401057, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38587966

RESUMEN

Oxygen evolution reaction (OER) is a widely employed half-electrode reaction in oxygen electrochemistry, in applications such as hydrogen evolution, carbon dioxide reduction, ammonia synthesis, and electrocatalytic hydrogenation. Unfortunately, its slow kinetics limits the commercialization of such applications. It is therefore highly imperative to develop highly robust electrocatalysts with high activity, long-term durability, and low noble-metal contents. Previously intensive efforts have been made to introduce the advancements on developing non-precious transition metal electrocatalysts and their OER mechanisms. Electronic structure tuning is one of the most effective and interesting ways to boost OER activity and spin angular momentum is an intrinsic property of the electron. Therefore, modulation on the spin states and the magnetic properties of the electrocatalyst enables the changes on energy associated with interacting electron clouds with radical absorbance, affecting the OER activity and stability. Given that few review efforts have been made on this topic, in this review, the-state-of-the-art research progress on spin-dependent effects in OER will be briefed. Spin engineering strategies, such as strain, crystal surface engineering, crystal doping, etc., will be introduced. The related mechanism for spin manipulation to boost OER activity will also be discussed. Finally, the challenges and prospects for the development of spin catalysis are presented. This review aims to highlight the significance of spin engineering in breaking the bottleneck of electrocatalysis and promoting the practical application of high-efficiency electrocatalysts.

2.
Small ; 20(21): e2309363, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38098307

RESUMEN

The challenge of the practical application of a water electrolyzer system lies in the development of low-manufacturing cost, highly active, and stable electrocatalysts to replace the noble metal ones, in order to enable environmentally friendly hydrogen production on a large scale. Herein, a facile method is proposed for boosting the performance of Co3O4 through the incorporation of large-sized single atoms. Due to the larger ionic radius of rare earth metals than that of Co, the incorporation elongates the bond length of Co─O, resulting in the narrowed d-p band centers and the high spin configuration, which is favorable for the interaction and charge transfer with absorbent (*OH). As a result, the Ce-incorporated Co3O4 with the longest Co─O bond length exhibits the best oxygen evolution reaction (OER) performance, specifically, the turnover frequency is over 17 times higher than that of pristine Co3O4 nanosheet under an overpotential of 400 mV. Powered by a commercial Si solar cell, a two-electrode solar water-splitting device combining Ce-incorporated Co3O4 and Pt delivers a solar-to-hydrogen conversion efficiency of 13.53%. The strategy could provide a new insight for improving the performance of OER electrocatalysts in acid toward practical applications.

3.
J Nutr ; 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39303797

RESUMEN

BACKGROUND: Silent information regulator protein 1 (Sirt1) is crucial in regulating lipid metabolism, but its specific role and mechanism in fish hepatic lipotoxic injury remain undefined. OBJECTIVES: This study aimed to elucidate the regulatory role of Sirt1 and the underlying mechanisms in dietary lipid-induced hepatic lipotoxic injury in a marine teleost black seabream. METHODS: Black seabream were fed a control diet (12% lipid level), high-fat diet (HFD) [18% lipid level, oleic acid (OA)-rich], or HFD supplemented with 0.25%, 0.50%, or 1.00% resveratrol (RSV) for 8 wk. The cultured hepatocytes were stimulated by OA (200 µM), OA supplemented with RSV (20 µM), or transfection with sirt1-small interfering RNA (sisirt1). Biochemical indices, gene expression (qPCR), histology, transmission electron microscope, immunofluorescence, Western blot, flow cytometry, and immunoprecipitation assays were conducted to evaluate hepatic lipid deposition, lipid metabolism, endoplasmic reticulum stress, inflammation and apoptosis, and determine protein interactions between Sirt1 and Ire1α. RESULTS: In vivo, RSV supplementation increased mRNA and protein expression levels of sirt1 (236.2% ± 16.1% and 53.1% ± 14.3%) and downregulated the mRNA and phosphorylated protein expression levels of ire1α/Ire1α (46.0% ± 7.6% and 38.6% ± 7.0%), jnk/Jnk (57.6% ± 7.3% and 122.1%), and nuclear factor κ B (nf-κb/Nf-κb) p65 (41.7% ± 7.1% and 24.6% ± 0.8%) compared with the HFD group. Similar patterns were found in the in vitro experiments; however, after knockdown of sirt1, although the cells were incubated with RSV, the expression levels of ire1α/ Ire1α, jnk/Jnk, and nf-κb/Nf-κb p65 showed no significant differences compared with the OA treatment. Moreover, we found that mutation of K61 to arginine to mimic Ire1α deacetylation confers protection against Ire1α-mediated OA-rich HFD-induced inflammation and apoptosis. CONCLUSIONS: The findings revealed that Sirt1 protects against OA-rich HFD-induced hepatic lipotoxic injury via the deacetylation of Ire1α on K61, hence reducing Ire1α autophosphorylation level, and suppressing Jnk and Nf-κb p65 activation. This mechanism is elucidated for the first time in fish.

4.
Inorg Chem ; 63(4): 1947-1953, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38215462

RESUMEN

Oxygen evolution reaction (OER) plays an important role in energy conversion processes such as water electrolysis and metal-air batteries. At present, finding a high-performance and low-cost catalyst for the OER in acidic media remains a great challenge. It is therefore important to develop efficient, robust, and inexpensive electrocatalysts by replacing noble metal-based catalysts with transition-metal electrocatalysts. Herein, we propose a facile method for incorporating Ce-metal single atoms into Co3O4 nanosheets to boost their OER activity and stability. Owing to the enhanced charge transfer and improved electronic structure resulting from Ce incorporation, the obtained Ce single-atom-doped Co3O4 nanosheet exhibits greatly enhanced OER performance. It achieves a 10 mA cm-2 current density under a low overpotential of 348 mV in a 0.5 M H2SO4 solution with excellent stability, outperforming the state-of-the-art non-noble electrocatalysts recently reported in acid.

5.
Sci Technol Adv Mater ; 25(1): 2309912, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38333111

RESUMEN

The control incorporation of metals in silica hollow spheres (SHSs) may bring new functions to silica mesoporous structures for applications including catalysis, sensing, molecular delivery, adsorption filtration, and storage. However, the strategies for incorporating metals, whether through pre-loading in the hollow interior or post-encapsulation in the mesoporous shell, still face challenges in achieving quantitative doping of various metals and preventing metal aggregation or channel blockage during usage. In this study, we explored the doping of different metals into silica hollow spheres based on the dissolution-regrowth process of silica. The process may promote the formation of more structural defects and functional silanol groups, which could facilitate the fixation of metals in the silica networks. With this simple and efficient approach, we successfully achieved the integration of ten diverse metal species into silica hollow sphere (SHS). Various single-metal, dual-metal, triple-metal, and quadruple-metal doped SHSs have been prepared, with the doped metals being stable and homogeneously dispersed in the structure. Based on the structural characterizations, we analyzed the influence of metal types on the morphology features of SHSs. The synergistic effects of multi-metals on the catalysis applications were also studied and compared.


Significance of this work: The control incorporation of metals in silica hollow spheres (SHSs) may bring new functions to silica mesoporous structures for applications including catalysis, sensing, molecular delivery, adsorption filtration, and storage. The incorporation of metals within SHSs is always either at the interior core or in the porous shells. The former method mainly utilizes metal nanoparticles as the core and regulates the synthesis of outer porous silica shells. The latter is primarily driven by the capillary force or intermolecular interactions with surface ligands to facilitate the post-loading of metal species in porous silica structures. The main problems associated with metal-doped SHSs include 1) controlled loading of different metals with a homogeneous distribution; 2) fixation of metal species in the structures to prevent aggregation during usage, particularly at high temperatures; 3) pore channel blockage after metal loading, which may hinder the loading of other external molecules. In this work, we developed the dissolution-regrowth of silica strategy for integrating various metals in porous SHSs (M@SHSs) by a one-pot hydrothermal process without using any anchoring molecules. Unlike other sol-gel formations, the growth rate of silica in this process is greatly reduced. It thus may bring more possibilities to introduce external metals within the silica frameworks instead of in the porous channels. By regulating the addition of metal salts in the silica nanoparticles dispersions, we have successfully synthesized stable and highly homogeneous single-metal, dual-metal, triple-metal, and quadruplemetal doped SHSs. Based on the structural characterizations, we analyzed the influence of metal types on the morphology features of SHSs. The synergistic effects of multi-metals on the catalysis applications were also studied and compared. Our results offer a facile and effective strategy for preparing multi-metals as nano-catalysts. Through proper design of the doped metals in SHSs, the structures should find more applications in catalysis, drug delivery, and adsorption with unique and enhanced properties.

6.
J Biol Chem ; 298(2): 101565, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34999119

RESUMEN

Trehalose is the major "blood sugar" of insects and it plays a crucial role in energy supply and as a stress protectant. The hydrolysis of trehalose occurs only under the enzymatic control of trehalase (Treh), which plays important roles in growth and development, energy supply, chitin biosynthesis, and abiotic stress responses. Previous reports have revealed that the vital hormone 20-hydroxyecdysone (20E) regulates Treh, but the detailed mechanism underlying 20E regulating Treh remains unclear. In this study, we investigated the function of HaTreh1 in Helicoverpa armigera larvae. The results showed that the transcript levels and enzymatic activity of HaTreh1 were elevated during molting and metamorphosis stages in the epidermis, midgut, and fat body, and that 20E upregulated the transcript levels of HaTreh1 through the classical nuclear receptor complex EcR-B1/USP1. HaTreh1 is a mitochondria protein. We also found that knockdown of HaTreh1 in the fifth- or sixth-instar larvae resulted in weight loss and increased mortality. Yeast two-hybrid, coimmunoprecipitation, and glutathione-S-transferase (GST) pull-down experiments demonstrated that HaTreh1 bound with ATP synthase subunit alpha (HaATPs-α) and that this binding increased under 20E treatment. In addition, 20E enhanced the transcript level of HaATPs-α and ATP content. Finally, the knockdown of HaTreh1 or HaATPs-α decreased the induction effect of 20E on ATP content. Altogether, these findings demonstrate that 20E controls ATP production by up-regulating the binding of HaTreh1 to HaATPs-α in H. armigera.


Asunto(s)
Ecdisterona , Proteínas de Insectos , Mariposas Nocturnas , Trehalasa , Adenosina Trifosfato/metabolismo , Animales , Ecdisterona/metabolismo , Proteínas de Insectos/metabolismo , Larva/metabolismo , ATPasas de Translocación de Protón Mitocondriales/metabolismo , Mariposas Nocturnas/enzimología , Mariposas Nocturnas/genética , Trehalasa/metabolismo , Trehalosa/metabolismo
7.
Cancer Sci ; 114(5): 2014-2028, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36715549

RESUMEN

Increasing evidence indicates that angiogenesis plays a pivotal role in tumor progression. Formin-like 2 (FMNL2) is well-known for promoting metastasis; however, the molecular mechanisms by which FMNL2 promotes angiogenesis in colorectal cancer (CRC) remain unclear. Here, we found that FMNL2 promotes angiogenesis and metastasis of CRC in vitro and in vivo. The GDB/FH3 domain of FMNL2 directly interacts with epidermal growth factor-like protein 6 (EGFL6). Formin-like 2 promotes EGFL6 paracrine signaling by exosomes to regulate angiogenesis in CRC. Cytoskeleton associated protein 4 (CKAP4) is a downstream target of EGFL6 and is involved in CRC angiogenesis. Epidermal growth factor-like protein 6 binds to the N-terminus of CKAP4 to promote the migration of HUVECs by activating the ERK/MMP pathway. These findings suggest that FMNL2 promotes the migration of HUVECs and enhances angiogenesis and tumorigenesis in CRC by regulating the EGFL6/CKAP4/ERK axis. Therefore, the EGFL6/CKAP4/ERK axis could be a candidate therapeutic target for CRC treatment.


Asunto(s)
Neoplasias Colorrectales , Citoesqueleto , Humanos , Proteínas de Unión al Calcio/genética , Moléculas de Adhesión Celular/metabolismo , Línea Celular Tumoral , Neoplasias Colorrectales/patología , Citoesqueleto/metabolismo , Familia de Proteínas EGF/metabolismo , Forminas/metabolismo , Proteínas de la Membrana/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo
8.
Plant Biotechnol J ; 21(10): 2033-2046, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37384619

RESUMEN

Sugar deficiency is the persistent challenge for plants during development. Trehalose-6-phosphate (T6P) is recognized as a key regulator in balancing plant sugar homeostasis. However, the underlying mechanisms by which sugar starvation limits plant development are unclear. Here, a basic helix-loop-helix (bHLH) transcription factor (OsbHLH111) was named starvation-associated growth inhibitor 1 (OsSGI1) and the focus is on the sugar shortage of rice. The transcript and protein levels of OsSGI1 were markedly increased during sugar starvation. The knockout mutants sgi1-1/2/3 exhibited increased grain size and promoted seed germination and vegetative growth, which were opposite to those of overexpression lines. The direct binding of OsSGI1 to sucrose non-fermenting-1 (SNF1)-related protein kinase 1a (OsSnRK1a) was enhanced during sugar shortage. Subsequently, OsSnRK1a-dependent phosphorylation of OsSGI1 enhanced the direct binding to the E-box of trehalose 6-phosphate phosphatase 7 (OsTPP7) promoter, thus rose the transcription inhibition on OsTPP7, then elevated trehalose 6-phosphate (Tre6P) content but decreased sucrose content. Meanwhile, OsSnRK1a degraded phosphorylated-OsSGI1 by proteasome pathway to prevent the cumulative toxicity of OsSGI1. Overall, we established the OsSGI1-OsTPP7-Tre6P loop with OsSnRK1a as center and OsSGI1 as forward, which is activated by sugar starvation to regulate sugar homeostasis and thus inhibits rice growth.


Asunto(s)
Oryza , Azúcares , Azúcares/metabolismo , Oryza/genética , Oryza/metabolismo , Trehalosa/metabolismo , Plantas/metabolismo , Sacarosa/metabolismo , Fosfatos/metabolismo , Regulación de la Expresión Génica de las Plantas/genética
9.
Rev Cardiovasc Med ; 24(11): 325, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39076451

RESUMEN

Background: Systematic evaluation of the effects of vitamin D supplementation in heart failure (HF) patients. Methods: Searches were conducted on National Library of Medicine, Web of Science, Cochrane Library, Google Scholar, China National Knowledge Infrastructure, and WANFANG databases. We analyzed data by using Review Manager 5.4 software. All are from the earliest records to March 2023. Outcome indicators analyzed the left ventricular ejection fraction (LVEF), the left ventricular end-diastolic internal diameter (LVEDD), the B-type brain natriuretic peptide (BNP) level and the 25-hydroxy vitamin D (25(OH)D) level. Results: Ten studies with 1099 patients were included. LVEF (mean difference (MD) = 0.74, 95% CI: -0.29 to 1.76, p = 0.41), LVEDD (MD = -0.59, 95% CI: -1.83 to 0.66, p = 0.25), BNP (MD = -0.08, 95% CI: -0.24 to 0.08, p = 0.34), 25(OH)D (MD = 0.41, 95% CI: -0.28 to 1.11, p = 0.25) are not statistically significant. And there is no heterogeneity in the results of LVEF, LVEDD and BNP indicators. Conclusions: Vitamin D supplementation may not be helpful in the clinical management of patients with HF.

10.
Inorg Chem ; 62(42): 17522-17529, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37826858

RESUMEN

Nonlinear optical (NLO) materials have aroused increasing interest owing to their promising applications in optoelectronic technologies. Herein, we present the synthesis of an acentric niobium tellurite crystal, Nb2Te3O11, extracted via a spontaneous crystallization approach. It adopts a unique three-dimensional (3D) structure constructed by the distorted [TeO3], [TeO4], and [NbO6] fundamental building units. The title compound undergoes incongruent melting at approximately 807 °C. Optical characterizations demonstrate that Nb2Te3O11 possesses an extended transparency window beyond 5 µm, along with a large band gap value of 3.1 eV. Moreover, the as-synthesized Nb2Te3O11 displays an appreciable second-harmonic generation (SHG) response of 2 × KDP and a notable birefringence of 0.11 under 1064 nm for achieving phase-matching. In addition, theoretical calculation investigations suggest that the intriguing optical properties are ascribed to the cooperative effect of three types of NLO-active motifs: [TeO3] pyramids, [TeO4] seesaws, and [NbO6] octahedra. These attributes provide new functional insights into Nb2Te3O11 and enrich the family of NLO crystals in the mid-infrared region.

11.
Fish Shellfish Immunol ; 143: 109212, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37926203

RESUMEN

The present study aimed to reveal the role of inositol-requiring enzyme 1α (Ire1α) in mediating high-fat-diet (HFD) induced inflammation and apoptosis in fish and elucidate underling mechanisms of action. In experiment 1, black seabream juveniles were fed a control diet (Control, 12 % dietary lipid) or a high fat diet (HFD, 19 % dietary lipid) for eight weeks. In experiment 2, primary hepatocytes were isolated from black seabream juveniles and treated with oleic acid (OA, 200 µmol/L), OA + transfection with non-silencing control siRNA (negative control) (OA + NC), and OA + transfection with ire1α-small interfering RNA (OA + siire1α) for 48 h versus untreated (Control). Results indicated that fish fed HFD increased lipid deposition in the liver and caused hepatic steatosis. HFD group had significantly higher ire1α/Ire1α mRNA and phosphorylated protein expression and endoplasmic reticulum stress (ERS) related genes expression compared to the Control group, indicating that ERS was triggered. Meanwhile, feeding HFD induced inflammation and apoptosis by evaluated nuclear factor kappa B (nf-κb) mRNA and phosphorylated Nf-κb p65 protein expression, and c-Jun N-terminal kinase (jnk) mRNA and protein expression. However, knock down of ire1α (OA + siire1α) in primary hepatocytes alleviated OA-induced increased expression of ire1α/Ire1α mRNA and protein expression, nf-κb/Nf-κb p65 mRNA and phosphorylated protein expression, and jnk/Jnk mRNA and phosphorylated protein expression. These findings revealed the underling mechanism of action of HFD in fish, confirming that HFD increased ESR stress and Ire1α that, in turn, activated Nf-κb and Jnk pathways in hepatocytes and liver mediating HFD-induced inflammation and apoptosis.


Asunto(s)
Dorada , Animales , Dorada/metabolismo , FN-kappa B/metabolismo , Dieta Alta en Grasa/efectos adversos , Dieta Alta en Grasa/veterinaria , Endorribonucleasas/genética , Endorribonucleasas/metabolismo , Inositol , Proteínas Serina-Treonina Quinasas/genética , Hígado/metabolismo , Hepatocitos/metabolismo , Apoptosis , Inflamación/veterinaria , Inflamación/metabolismo , Grasas de la Dieta/metabolismo , ARN Mensajero/metabolismo , Estrés del Retículo Endoplásmico
12.
Bioorg Med Chem ; 91: 117385, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37364415

RESUMEN

Receptor-interacting protein kinase 1 (RIPK1)-mediated necroptosis is believed to have a significant role in contributing to inflammatory diseases. Inhibiting RIPK1 has shown promise in effectively alleviating the inflammation process. In our current study, we employed scaffold hopping to develop a series of novel benzoxazepinone derivatives. Among these derivatives, compound o1 displayed the most potent antinecroptosis activity (EC50=16.17±1.878nM) in cellular assays and exhibited the strongest binding affinity to the target site. Molecular docking analyses further elucidated the mechanism of action of o1, revealing its ability to fully occupy the protein pocket and form hydrogen bonds with the amino acid residue Asp156. Our findings highlight that o1 specifically inhibits necroptosis, rather than apoptosis, by impeding the RIPK1/Receptor-interacting protein kinase 3 (RIPK3)/mixed-lineage kinase domain-like (MLKL) pathway's phosphorylation, triggered by TNFα, Smac mimetic, and z-VAD (TSZ). Additionally, o1 demonstrated dose-dependent improvements in the survival rate of mice with Systemic Inflammatory Response Syndrome (SIRS), surpassing the protective effect observed with GSK'772.


Asunto(s)
Necroptosis , Inhibidores de Proteínas Quinasas , Proteína Serina-Treonina Quinasas de Interacción con Receptores , Animales , Ratones , Apoptosis , Simulación del Acoplamiento Molecular , Fosforilación , Proteínas Quinasas/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/antagonistas & inhibidores , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Necroptosis/efectos de los fármacos , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología
13.
Fish Physiol Biochem ; 49(6): 1115-1128, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37855969

RESUMEN

Glucose-regulated protein 78 (grp78) and activating transcription factor 6α (atf6α) are considered vital endoplasmic reticulum (ER) molecular chaperones and ER stress (ERS) sensors, respectively. In the present study, the full cDNA sequences of these two ERS-related genes were first cloned and characterized from black seabream (Acanthopagrus schlegelii). The grp78 cDNA sequence is 2606 base pair (bp) encoding a protein of 654 amino acids (aa). The atf6α cDNA sequence is 2168 base pair (bp) encoding a protein of 645 aa. The predicted aa sequences of A. schlegelii grp78 and atf6α indicated that the proteins contain all the structural features, which were characteristic of the two genes in other species. Tissues transcript abundance analysis revealed that the mRNAs of grp78 and atf6α were expressed in all measured tissues, but the highest expression of these two genes was all recorded in the gill followed by liver/ brain. Moreover, in vivo experiment found that fish intake of a high lipid diet (HLD) can trigger ERS by activating grp78/Grp78 and atf6α/Atf6α. However, it can be alleviated by dietary betaine supplementation, similar results were also obtained by in vitro experiment using primary hepatocytes of A. schlegelii. These findings will be beneficial for us to evaluate the regulator effects of HLD supplemented with betaine on ERS at the molecular level, and thus provide some novel insights into the functions of betaine in marine fish fed with an HLD.


Asunto(s)
Perciformes , Dorada , Animales , Chaperón BiP del Retículo Endoplásmico , Dorada/genética , Betaína , ADN Complementario/genética , Perciformes/genética , Estrés del Retículo Endoplásmico , Factores de Transcripción Activadores/genética , Clonación Molecular
14.
Int Wound J ; 21(3): e14468, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38050652

RESUMEN

Studies showed that integrating coating or valve into Peripherally Inserted Central (PICC) can prevent related complications. However, data regarding efficiency were controversial. Therefore, a systematic review was needed to analyse the effect of PICC materials and designs on reduction of PICC-related complications. We searched PubMed, Cochrane library, EMbase, grey literature and referent literature from inception to 5 August 2022. Randomized controlled trials (RCTs) and case-control study were included. Two authors extracted data independently, using a predesigned Excel form, and assessed the quality of included RCTs according to the Cochrane Handbook for Systematic Reviews (V5.1.0), case-control study was assessed by the Newcastle-Ottawa Scale. Data were analysed using Review Manager (v5.3.0). A total of 10 RCTs and one case-control study were included. Meta-analysis results showed that PICC designs reduce the incidence of obstruction, and at the critical value of PICC-associated bloodstream infection, but may have no effects on other complications. Based on the literature reviewed, we can only say PICC new materials did not reflect significant reduction on complications, what's more, the result needs more multicentre, large RCTs to support. We suggested clinicians combine descriptive research and cost-effect analysis to select appropriate PICC materials and designs for patients.

15.
Small ; 18(50): e2205495, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36310342

RESUMEN

The sluggish kinetics of the oxygen evolution reaction (OER) limits the commercialization of oxygen electrochemistry, which plays a key role in renewable energy technologies such as fuel cells and electrolyzers. Herein, a facile and practical strategy is developed to successfully incorporate Ir single atoms into the lattice of transition metal oxides (TMOs). The chemical environment of Ir and its neighboring lattice oxygen is modulated, and the lattice oxygen provides lone-pair electrons and charge balance to stabilize Ir single atoms, resulting in the enhancement of both OER activity and durability. In particular, Ir0.08 Co2.92 O4 NWs exhibit an excellent mass activity of 1343.1 A g-1 and turnover frequency (TOF) of 0.04 s-1 at overpotentials of 300 mV. And this catalyst also displays significant stability in acid at 10 mA cm-2 over 100 h. Overall water splitting using Pt/C as the hydrogen evolution reaction catalyst and Ir0.08 Co2.92 O4 NWs as the OER catalyst takes only a cell voltage of 1.494 V to achieve 10 mA cm-2 with a perfect stability. This work demonstrates a simple approach to produce highly active and acid-stable transition metal oxides electrocatalysts with trace Ir.

16.
Plant Cell Environ ; 45(3): 900-914, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34490900

RESUMEN

Plant root morphology is constantly reshaped in response to triggers from the soil environment. Such modifications in root system architecture involve changes in the abundance of reactive oxygen species (ROS) in the apoplast and in cell wall (CW) composition. The hybrid proline-rich proteins (HyPRPs) gene family in higher plants is considered important in the regulation of CW structure. However, the functions of HyPRPs remain to be characterized. We therefore analysed the functions of OsR3L1 (Os04g0554500) in rice. qRT-PCR and GUS staining revealed that OsR3L1 is expressed in roots. While the r3l1 mutants had a defective root system with fewer adventitious roots (ARs) and lateral roots (LRs) than the wild type, lines overexpressing OsR3L1 (R3L1-OE) showed more extensive LR formation but with a shorter root length. The expression of OsR3L1 was initiated by the OsMADS25 transcription factor. Moreover, the abundance of OsR3L1 transcripts was increased by NaCl. The R3L1-OE-3 line exhibited enhanced salt tolerance, whereas the r3l1-2 mutant showed greater salt sensitivity. The addition of H2 O2 increased the levels of OsR3L1 transcripts. Data are presented indicating that OsR3L1 modulates H2 O2 accumulation in the apoplast. We conclude that OsR3L1 regulates salt tolerance through regulation of peroxidases and apoplastic H2 O2 metabolism.


Asunto(s)
Oryza , Regulación de la Expresión Génica de las Plantas , Homeostasis , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Tolerancia a la Sal/genética
17.
Insect Mol Biol ; 31(3): 334-345, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35084068

RESUMEN

Trehalase (Treh) hydrolyzes trehalose to generate glucose and it plays important role in many physiological processes. Acetyl-CoA, the precursor of sex pheromone biosynthesis in the pheromone gland (PG) of Helicoverpa armigera, originates from glucose during glycolysis. However, the function of Treh in sex pheromone biosynthesis remains elusive. In the present study, H. armigera was used as a model to investigate the function of two Trehs (Treh1 and Treh2) in sex pheromone biosynthesis. Results demonstrated that knockdown of HaTreh1 or HaTreh2 in female PGs led to significant decreases in Z11-16:Ald production, female ability to attract males, and successful mating proportions. Pheromone biosynthesis activating neuropeptide (PBAN) treatment triggered HaTreh1 and HaTreh2 activities in the isolated PGs and Sf9 cells. However, the activities of HaTreh1 and HaTreh2 triggered by PBAN were offset by H-89, the specific inhibitor of protein kinase A (PKA). Furthermore, the H-89 treatment significantly decreased the phosphorylation level of Trhe2, which was induced by PBAN. In addition, sugar feeding (5% sugar) increased the enzyme activities of Treh1 and Treh2. In summary, our findings confirmed that PBAN activates Treh1/2 activities by recruiting cAMP/PKA signalling, promotes glycolysis to ensure the supply of acetyl-CoA, and ultimately facilitates sex pheromone biosynthesis and mating behaviour.


Asunto(s)
Mariposas Nocturnas , Neuropéptidos , Atractivos Sexuales , Acetilcoenzima A/metabolismo , Animales , Femenino , Glucosa/metabolismo , Masculino , Mariposas Nocturnas/metabolismo , Neuropéptidos/genética , Neuropéptidos/metabolismo , Atractivos Sexuales/metabolismo , Azúcares/metabolismo , Trehalasa/genética , Trehalasa/metabolismo
18.
Insect Mol Biol ; 31(5): 647-658, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35652818

RESUMEN

The biosynthesis and termination of insect sex pheromones should be accurately regulated. In most moths, the biosynthesis and release of sex pheromones are regulated by a class of neuropeptides known as pheromone biosynthesis activating neuropeptides (PBANs). However, endogenous mechanisms underlying the termination of sex pheromone biosynthesis in moths remain elusive. In the present study, Helicoverpa armigera was employed as a model to investigate the role of octopamine (OA) in the inhibition of sex pheromone biosynthesis. Results demonstrated that the release of sex pheromones decreased with an increase in OA titres in older female moths. Moreover, OA treatment led to a significant decrease in sex pheromone production, female capability to attract male counterparts and subsequent female acceptance, indicating its inhibitory role in sex pheromone release. Subsequent qPCR and RNAi analyses revealed that OctßR was a key receptor of OA that regulated sex pheromone biosynthesis. In addition, the OA/OctßR signal suppressed intracellular Ca2+ levels and attenuated PBAN-mediated increase in the enzyme activities of calcineurin and acetyl-CoA carboxylase as demonstrated by OA treatment and OctßR-RNAi. Altogether, these results revealed a mechanism underlying the inhibition of sex pheromone production by OA via suppression of PBAN signalling in moths.


Asunto(s)
Mariposas Nocturnas , Neuropéptidos , Atractivos Sexuales , Animales , Calcineurina , Femenino , Masculino , Mariposas Nocturnas/genética , Neuropéptidos/genética , Octopamina
19.
J Endovasc Ther ; : 15266028221139194, 2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36444636

RESUMEN

PURPOSE: We evaluated the feasibility and safety of using a new unibody outer double-branched stent-graft system to reconstruct the canine ascending aorta, aortic arch, and supra-aortic vessels. MATERIALS AND METHODS: The outer-branched stent-graft was a unibody design. The branched stent-graft consisted of a main stent-graft and 2 branches. The introducer system included a tri-channel catheter, 2 detachable sleeves, a front fixing device, a constraining wire, and a curved outer sheath. The branched stent-graft was loaded into the introducer system. Ten adult mongrel dogs underwent general anesthesia, and the branched stent-grafts were deployed into the canine ascending aorta, aortic arch, and supra-aortic vessels by the introducer system. All animals were followed up for 3 months. At the end of the follow-up period, computed tomographic angiography (CTA) was performed to observe the patency of the branched stent-grafts. RESULTS: The mean operation time was 142.7±13.7 minutes. The mean fluoroscopy time was 20.73±2.22 minutes. The mean dosage of contrast agent was 95.9±8.7 mL. During the operation, the tri-channel catheters successfully paralleled the wires in the aorta. All 10 branched stent-grafts were successfully implanted into the canine ascending aorta and aortic arch. There were no symptoms of cerebral embolization and no incision infection during the follow-up period. Computed tomographic angiography and specimens showed that the branched stent-grafts and native vessels were patent, the inner surfaces of the branched stent-grafts were covered by neointima, and there was no retrograde aortic dissection in the ascending aorta. CONCLUSIONS: This animal research demonstrated that the unibody outer double-branched stent-graft system could be applied to reconstruct the canine ascending aorta, aortic arch, and supra-aortic vessels. CLINICAL IMPACT: Thoracic endovascular aortic repair has been the main treatment method for aortic aneurysms or dissections involving the descending thoracic aorta. However, the aortic arch and ascending aorta remain the last segments of the aorta without a validated and routinely used endovascular option. In this research, we designed a new unibody outer branched stent-graft system to reconstruct the distal ascending aorta, aortic arch and supra-aortic vessels. The unibody outer branched stent-graft system could be applied to treat aortic pathologies which involve the middle and distal proximal ascending aorta, aortic arch and proximal descending aorta.

20.
Inorg Chem ; 61(1): 706-712, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-34935373

RESUMEN

A quaternary nonlinear-optical (NLO) zinc germanate, Rb2ZnGe2O6 (RZGO), was prepared from its stoichiometric melts, which belongs to the noncentrosymmetric space group C2221 (No. 20) and features a 3D framework formed by GeO4 tetrahedra, ZnO4 tetrahedra, and Rb+ cations filling into the void space. RZGO displays a good phase-matchable second-harmonic-generation (SHG) intensity similar to that of KH2PO4. The UV cutoff edge for RZGO was found to be approximately 0.37 µm with a broad optical band gap of 3.22 eV, indicating a large laser-induced damage threshold. Further characterizations suggested that this compound displays an excellent thermal stability (1014 °C) and melts congruently. Besides, theoretical analysis was also implemented to investigate the electronic structures and effective NLO coefficients as well as the origin of the observed SHG response for RZGO. The present study can enrich the diversity of acentric germanate structures and pave the way for the synthesis of new NLO compounds.

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