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1.
Angew Chem Int Ed Engl ; : e202411029, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38955769

RESUMO

Graphite (Gr)-based lithium-ion batteries with admirable electrochemical performance below -20 °C are desired but are hindered by sluggish interfacial charge transport and desolvation process. Li salt dissociation via Li+-solvent interaction enables mobile Li+ liberation and contributes to bulk ion transport, while is contradictory to fast interfacial desolvation. Designing kinetically-stable solid electrolyte interphase (SEI) without compromising strong Li+-solvent interaction is expected to compatibly improve interfacial charge transport and desolvation kinetics. However, the relationship between physicochemical features and temperature-dependent kinetics properties of SEI remains vague. Herein, we propose four key thermodynamics parameters of SEI potentially influencing low-temperature electrochemistry, including electron work function, Li+ transfer barrier, surface energy, and desolvation energy. Based on the above parameters, we further define a novel descriptor, separation factor of SEI (SSEI), to quantitatively depict charge (Li+/e-) transport and solvent deprivation processes at Gr/electrolyte interface. A Li3PO4-based, inorganics-enriched SEI derived by Li difluorophosphate (LiDFP) additive exhibits the highest SSEI (4.89×103) to enable efficient Li+ conduction, e- blocking and rapid desolvation, and as a result, much suppressed Li-metal precipitation, electrolyte decomposition and Gr sheets exfoliation, thus improving low-temperature battery performances. Overall, our work originally provides visualized guides to improve low-temperature reaction kinetics/thermodynamics by constructing desirable SEI chemistry.

2.
Expert Rev Anti Infect Ther ; : 1-12, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38975666

RESUMO

BACKGROUND: The potential of ursodeoxycholic acid (UDCA) in inhibiting angiotensin-converting enzyme 2 was demonstrated. However, conflicting evidence emerged regarding the association between UDCA and COVID-19 outcomes, prompting the need for a comprehensive investigation. RESEARCH DESIGN AND METHODS: Patients diagnosed with COVID-19 infection were retrospectively analyzed and divided into two groups: the UDCA-treated group and the control group. Kaplan-Meier recovery analysis and Cox proportional hazards models were used to evaluate the recovery time and hazard ratios. Additionally, study-level pooled analyses for multiple clinical outcomes were performed. RESULTS: In the 115-patient cohort, UDCA treatment was significantly associated with a reduced recovery time. The subgroup analysis suggests that the 300 mg subgroup had a significant (adjusted hazard ratio: 1.63 [95% CI, 1.01 to 2.60]) benefit with a shorter duration of fever. The results of pooled analyses also show that UDCA treatment can significantly reduce the incidence of severe/critical diseases in COVID-19 (adjusted odds ratio: 0.68 [95% CI, 0.50 to 0.94]). CONCLUSIONS: UDCA treatment notably improves the recovery time following an Omicron strain infection without observed safety concerns. These promising results advocate for UDCA as a viable treatment for COVID-19, paving the way for further large-scale and prospective research to explore the full potential of UDCA.

3.
Biotechnol Bioeng ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978393

RESUMO

ß-Alanine is the only ß-amino acid in nature and one of the most important three-carbon chemicals. This work was aimed to construct a non-inducible ß-alanine producer with enhanced metabolic flux towards ß-alanine biosynthesis in Escherichia coli. First of all, the assembled E. coli endogenous promoters and 5'-untranslated regions (PUTR) were screened to finely regulate the combinatorial expression of genes panDBS and aspBCG for an optimal flux match between two key pathways. Subsequently, additional copies of key genes (panDBS K104S and ppc) were chromosomally introduced into the host A1. On these bases, dynamical regulation of the gene thrA was performed to reduce the carbon flux directed in the competitive pathway. Finally, the ß-alanine titer reached 10.25 g/L by strain A14-R15, 361.7% higher than that of the original strain. Under fed-batch fermentation in a 5-L fermentor, a titer of 57.13 g/L ß-alanine was achieved at 80 h. This is the highest titer of ß-alanine production ever reported using non-inducible engineered E. coli. This metabolic modification strategy for optimal carbon flux distribution developed in this work could also be used for the production of various metabolic products.

4.
Plant Physiol Biochem ; 214: 108925, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39002306

RESUMO

The effect mechanism of Mn on Cd uptake by Celosia argentea was investigated via a series of hydroponics experiments. The results showed that different manganese treatments had different effects on Cd uptake by C. argentea. Mn pretreatment increased Cd uptake by root protoplasts at Cd concentrations (4 and 6 µM). Protoplasts reached peak Cd uptake rate at 6 µM Cd and 25 °C, with 67.71 ± 0.13 µM h-1 mL-1 in the control, and 77.99 ± 0.49 µM h-1 mL-1 in the 50 µM Mn pretreatment group. However, simultaneous treatment with Cd and Mn reduced the Cd2+ uptake by root protoplasts. This discrepancy may be attributed to the fact that cadmium and manganese share some transporters in root cells. The transcriptome analysis in roots revealed that ten genes (including ABCC, ABCA, ABCG, ABCB, ABC1, BZIP19, and ZIP5) were significantly upregulated in response to Mn stress (p < 0.05). These genes regulate the expression of transporters belonging to the ABC, and ZIP families, which may be involved in Cd uptake by root cells of C. argentea. Mn pretreatment upregulates the expression of Mn/Cd transporters, enhancing Cd uptake by root protoplasts. For the simultaneous treatment of Cd and Mn, inhibition of Cd uptake was due to the competition of the same transporters. These findings provide helpful insights for understanding the mechanism of Mn and Cd uptake in hyperaccumulators and give implications to improve the phytoremediation of Cd-contaminated soil by C. argentea.

5.
Chem Soc Rev ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38962926

RESUMO

Rechargeable sodium-ion batteries (SIBs) have emerged as an advanced electrochemical energy storage technology with potential to alleviate the dependence on lithium resources. Similar to Li-ion batteries, the cathode materials play a decisive role in the cost and energy output of SIBs. Among various cathode materials, Na layered transition-metal (TM) oxides have become an appealing choice owing to their facile synthesis, high Na storage capacity/voltage that are suitable for use in high-energy SIBs, and high adaptivity to the large-scale manufacture of Li layered oxide analogues. However, going from the lab to the market, the practical use of Na layered oxide cathodes is limited by the ambiguous understanding of the fundamental structure-performance correlation of cathode materials and lack of customized material design strategies to meet the diverse demands in practical storage applications. In this review, we attempt to clarify the fundamental misunderstandings by elaborating the correlations between the electron configuration of the critical capacity-contributing elements (e.g., TM cations and oxygen anion) in oxides and their influence on the Na (de)intercalation (electro)chemistry and storage properties of the cathode. Subsequently, we discuss the issues that hinder the practical use of layered oxide cathodes, their origins and the corresponding strategies to address their issues and accelerate the target-oriented research and development of cathode materials. Finally, we discuss several new Na layered cathode materials that show prospects for next-generation SIBs, including layered oxides with anion redox and high entropy and highlight the use of layered oxides as cathodes for solid-state SIBs with higher energy and safety. In summary, we aim to offer insights into the rational design of high-performance Na layered oxide cathode materials towards the practical realization of sustainable electrochemical energy storage at a low cost.

6.
Biotechnol J ; 19(7): e2400287, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39014925

RESUMO

The d-amino acid oxidase (DAAO) is pivotal in obtaining optically pure l-glufosinate (l-PPT) by converting d-glufosinate (d-PPT) to its deamination product. We screened and designed a Rasamsonia emersonii DAAO (ReDAAO), making it more suitable for oxidizing d-PPT. Using Caver 3.0, we delineated three substrate binding pockets and, via alanine scanning, identified nearby key residues. Pinpointing key residues influencing activity, we applied virtual saturation mutagenesis (VSM), and experimentally validated mutants which reduced substrate binding energy. Analysis of positive mutants revealed elongated side-chain prevalence in substrate binding pocket periphery. Although computer-aided approaches can rapidly identify advantageous mutants and guide further design, the mutations obtained in the first round may not be suitable for combination with other advantageous mutations. Therefore, each round of combination requires reasonable iteration. Employing VSM-assisted screening multiple times and after four rounds of combining mutations, we ultimately obtained a mutant, N53V/F57Q/V94R/V242R, resulting in a mutant with a 5097% increase in enzyme activity compared to the wild type. It provides valuable insights into the structural determinants of enzyme activity and introduces a novel rational design procedure.


Assuntos
D-Aminoácido Oxidase , Engenharia de Proteínas , D-Aminoácido Oxidase/genética , D-Aminoácido Oxidase/metabolismo , D-Aminoácido Oxidase/química , Engenharia de Proteínas/métodos , Especificidade por Substrato , Mutagênese , Mutagênese Sítio-Dirigida/métodos , Aminobutiratos/metabolismo , Modelos Moleculares , Mutação , Sítios de Ligação
7.
Biotechnol Bioeng ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822747

RESUMO

D-amino acid oxidase (DAAO)-catalyzed selective oxidative deamination is a very promising process for synthesizing l-amino acids including l-phosphinothricin ( l-PPT, a high-efficiency and broad-spectrum herbicide). However, the wild-type DAAO's low activity toward unnatural substrates like d-phosphinothricin ( d-PPT) hampers its application. Herein, a DAAO from Caenorhabditis elegans (CeDAAO) was screened and engineered to improve the catalytic potential on d-PPT. First, we designed a novel growth selection system, taking into account the intricate relationship between the growth of Escherichia coli (E. coli) and the catalytic mechanism of DAAO. The developed system was used for high-throughput screening of gene libraries, resulting in the discovery of a variant (M6) with significantly increased catalytic activity against d-PPT. The variant displays different catalytic properties on substrates with varying hydrophobicity and hydrophilicity. Analysis using Alphafold2 modeling and molecular dynamic simulations showed that the reason for the enhanced activity was the substrate-binding pocket with enlarged size and suitable charge distribution. Further QM/MM calculations revealed that the crucial factor for enhancing activity lies in reducing the initial energy barrier of the reductive half reaction. Finally, a comprehensive binding-model index to predict the enhanced activity of DAAO toward d-PPT, and an enzymatic deracemization approach was developed, enabling the efficient synthesis of l-PPT with remarkable efficiency.

8.
J Agric Food Chem ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842002

RESUMO

The nicotinamide phosphoribosyltransferase (NAMPT)-catalyzed substitution reaction plays a pivotal role in the biosynthesis of nucleotide compounds. However, industrial applications are hindered by the low activity of NAMPTs. In this study, a novel dual-channel protein engineering strategy was developed to increase NAMPT activity by enhancing substrate accessibility. The best mutant (CpNAMPTY13G+Y15S+F76P) with a remarkable 5-fold increase in enzyme activity was obtained. By utilizing CpNAMPTY13G+Y15S+F76P as a biocatalyst, the accumulation of ß-nicotinamide mononucleotide reached as high as 19.94 g L-1 within 3 h with an impressive substrate conversion rate of 99.8%. Further analysis revealed that the newly generated substrate channel, formed through crack propagation, facilitated substrate binding and enhanced byproduct tolerance. In addition, three NAMPTs from different sources were designed based on the dual-channel protein engineering strategy, and the corresponding dual-channel mutants with improved enzyme activity were obtained, which proved the effectiveness and practicability of the approach.

9.
World J Otorhinolaryngol Head Neck Surg ; 10(2): 113-120, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38855290

RESUMO

Objective: This cross-sectional study aimed to determine the epidemiology of olfactory and gustatory dysfunctions related to COVID-19 in China. Methods: This study was conducted by 45 tertiary Grade-A hospitals in China. Online and offline questionnaire data were obtained from patients infected with COVID-19 between December 28, 2022, and February 21, 2023. The collected information included basic demographics, medical history, smoking and drinking history, vaccination history, changes in olfactory and gustatory functions before and after infection, and other postinfection symptoms, as well as the duration and improvement status of olfactory and gustatory disorders. Results: Complete questionnaires were obtained from 35,566 subjects. The overall incidence of olfactory and taste dysfunction was 67.75%. Being female or being a cigarette smoker increased the likelihood of developing olfactory and taste dysfunction. Having received four doses of the vaccine or having good oral health or being a alcohol drinker decreased the risk of such dysfunction. Before infection, the average olfactory and taste VAS scores were 8.41 and 8.51, respectively; after infection, they decreased to 3.69 and 4.29 and recovered to 5.83 and 6.55 by the time of the survey. The median duration of dysosmia and dysgeusia was 15 and 12 days, respectively, with 0.5% of patients having symptoms lasting for more than 28 days. The overall self-reported improvement rate was 59.16%. Recovery was higher in males, never smokers, those who received two or three vaccine doses, and those that had never experienced dental health issues, or chronic accompanying symptoms. Conclusions: The incidence of dysosmia and dysgeusia following infection with the SARS-CoV-2 virus is high in China. Incidence and prognosis are influenced by several factors, including sex, SARS-CoV-2 vaccination, history of head-facial trauma, nasal and oral health status, smoking and drinking history, and the persistence of accompanying symptoms.

10.
BMC Oral Health ; 24(1): 695, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879477

RESUMO

BACKGROUND: The status of dental caries is closely related to changes in the oral microbiome. In this study, we compared the diversity and structure of the dental plaque microbiome in children with severe early childhood caries (S-ECC) before and after general anaesthesia and outpatient treatment. METHODS: Forty children aged 3 to 5 years with S-ECC who had completed whole-mouth dental treatment under general anaesthesia (C1) or in outpatient settings (C2) were selected, 20 in each group. The basic information and oral health status of the children were recorded, and the microbial community structure and diversity of dental plaque before treatment (C1, C2), the day after treatment(C2_0D), 7 days after treatment (C1_7D, C2_7D), 1 month after treatment (C1_1M, C2_1M), and 3 months after treatment (C1_3M, C2_3M) were analysed via 16 S rRNA high-throughput sequencing technology. RESULTS: (1) The alpha diversity test showed that the flora richness in the multiappointment group was significantly greater at posttreatment than at pretreatment (P < 0.05), and the remaining alpha diversity index did not significantly differ between the 2 groups (P > 0.05). The beta diversity analysis revealed that the flora structures of the C1_7D group and the C2_3M group were significantly different from those of the other time points within the respective groups (P < 0.05). (2) The core flora existed in both the pre- and posttreatment groups, and the proportion of their flora abundance could be altered depending on the caries status of the children in both groups. Leptotrichia abundance was significantly (P < 0.05) lower at 7 days posttreatment in both the single- and multiappointment groups. Corynebacterium and Corynebacterium_matruchotii were significantly more abundant in the C1_1M and C1_3M groups than in the C1 and C1_7D groups (P < 0.05). Streptococcus, Haemophilus and Haemophilus_parainfluenzae were significantly more abundant in the C1_7D group than in the other groups (P < 0.05). CONCLUSION: A single session of treatment under general anaesthesia can cause dramatic changes in the microbial community structure and composition within 7 days after treatment, whereas treatment over multiple appointments may cause slow changes in oral flora diversity.


Assuntos
Cárie Dentária , Placa Dentária , Humanos , Placa Dentária/microbiologia , Cárie Dentária/microbiologia , Cárie Dentária/terapia , Pré-Escolar , Masculino , Feminino , Microbiota , Anestesia Geral , RNA Ribossômico 16S
12.
Angew Chem Int Ed Engl ; : e202409435, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38945832

RESUMO

Visualizing lithium (Li) ions and understanding Li plating/stripping processes as well as evolution of solid electrolyte interface (SEI) are critical for optimizing all-solid-state Li metal batteries (ASSLMB). However, the buried solid-solid interfaces present a challenge for detection which preclude the employment of multiple analysis techniques. Herein, by employing complementary in situ characterizations, morphological/chemical evolution, Li plating/stripping dynamics and SEI dynamics were efficiently decoupled and Li ion behavior at interface between different solid-state electrolytes (SSE) was successfully detected. The innovative combining experiments of in situ atomic force microscopy and in situ X-ray photoelectron spectroscopy on Li metal anode revealed interfacial morphological/chemical evolution and decoupled Li plating/stripping process from SEI evolution. Though Li plating speed in Li10GeP2S12 (LGPS) was higher than Li3PS4 (LPS), speed of SSE decomposition was similar and ~85% interfacial SSE turned into SEI during plating and remained unchanged in stripping. To leverage strengths of different SSEs, an LPS-LGPS-LPS sandwich electrolyte was developed, demonstrating enhanced ionic conductivity and improved interfacial stability with less SSE decomposition (25%). Using in situ Kelvin Probe Force Microscopy, Li-ion behavior at interface between different SSEs was effectively visualized, uncovering distribution of Li ions at LGPS|LPS interface under different potentials.

13.
Adv Mater ; : e2405238, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38923661

RESUMO

The ongoing tide of spent lithium-ion batteries (LIBs) urgently calls for high-value output in efficient recycling. Recently, direct regeneration has emerged as a novel recycling strategy but fails to repair the irreversible morphology and structure damage of the highly degraded polycrystalline layered oxide materials. Here, this work carries out a solid-state upcycling study for the severely cracked LiNi1-x-yCoxMnyO2 cathodes. The specific single-crystallization process during calcination is investigated and the surface rock salt phase is recognized as the intrinsic obstacle to the crystal growth of the degraded cathodes due to sluggish diffusion in the heterogeneous grain boundary. Accordingly, this work revives the fatigue rock salt phase by restoring a layered surface and successfully reshapes severely broken cathodes into the high-performance single-crystalline particles. Benefiting from morphological and structural integrity, the upcycled single-crystalline cathode materials exhibit an enhanced capacity retention rate of 93.5% after 150 cycles at 1C compared with 61.7% of the regenerated polycrystalline materials. The performance is also beyond that of the commercial cathodes even under a high cut-off voltage (4.5 V) or high operating temperature (45 °C). This work provides scientific insights for the upcycling of the highly degraded cathodes in spent LIBs.

14.
Nat Commun ; 15(1): 4985, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862515

RESUMO

Hyperglycemia accelerates calcification of atherosclerotic plaques in diabetic patients, and the accumulation of advanced glycation end products (AGEs) is closely related to the atherosclerotic calcification. Here, we show that hyperglycemia-mediated AGEs markedly increase vascular smooth muscle cells (VSMCs) NF90/110 activation in male diabetic patients with atherosclerotic calcified samples. VSMC-specific NF90/110 knockout in male mice decreases obviously AGEs-induced atherosclerotic calcification, along with the inhibitions of VSMC phenotypic changes to osteoblast-like cells, apoptosis, and matrix vesicle release. Mechanistically, AGEs increase the activity of NF90, which then enhances ubiquitination and degradation of AGE receptor 1 (AGER1) by stabilizing the mRNA of E3 ubiquitin ligase FBXW7, thus causing the accumulation of more AGEs and atherosclerotic calcification. Collectively, our study demonstrates the effects of VSMC NF90 in mediating the metabolic imbalance of AGEs to accelerate diabetic atherosclerotic calcification. Therefore, inhibition of VSMC NF90 may be a potential therapeutic target for diabetic atherosclerotic calcification.


Assuntos
Aterosclerose , Proteína 7 com Repetições F-Box-WD , Produtos Finais de Glicação Avançada , Camundongos Knockout , Músculo Liso Vascular , Miócitos de Músculo Liso , Proteínas do Fator Nuclear 90 , Receptor para Produtos Finais de Glicação Avançada , Animais , Masculino , Camundongos , Produtos Finais de Glicação Avançada/metabolismo , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Aterosclerose/metabolismo , Aterosclerose/genética , Aterosclerose/patologia , Humanos , Proteína 7 com Repetições F-Box-WD/metabolismo , Proteína 7 com Repetições F-Box-WD/genética , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Proteínas do Fator Nuclear 90/metabolismo , Proteínas do Fator Nuclear 90/genética , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Receptor para Produtos Finais de Glicação Avançada/genética , Calcificação Vascular/metabolismo , Calcificação Vascular/patologia , Calcificação Vascular/genética , Camundongos Endogâmicos C57BL , Ubiquitinação , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Hiperglicemia/metabolismo , Hiperglicemia/genética , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Placa Aterosclerótica/genética , Apoptose
15.
Materials (Basel) ; 17(9)2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38730890

RESUMO

A modified 3D re-entrant honeycomb is designed and fabricated utilizing Laser Cladding Deposition (LCD) technology, the mechanical properties of which are systematically investigated by experimental and finite element (FE) methods. Firstly, the influences of honeycomb angle on localized deformation and the response of force are studied by an experiment. Experimental results reveal that the honeycomb angles have a significant effect on deformation and force. Secondly, a series of numerical studies are conducted to analyze stress characteristics and energy absorption under different angles (α) and velocities (v). It is evident that two variables play an important role in stress and energy. Thirdly, response surface methodology (RSM) and the Non-Dominated Sorting Genetic Algorithm II (NSGA-II) are implemented with high precision to solve multi-objective optimization. Finally, the final compromise solution is determined based on the fitness function, with an angle of 49.23° and an impact velocity of 16.40 m/s. Through simulation verification, the errors of energy absorption (EA) and peak crush stress (PCS) are 9.26% and 0.4%, respectively. The findings of this study offer valuable design guidance for selecting the optimal design parameters under the same mass conditions to effectively enhance the performance of the honeycomb.

17.
J Hazard Mater ; 472: 134551, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38743979

RESUMO

Most hyperaccumulators cannot maintain vigorous growth throughout the year, which may result in a low phytoextraction efficiency for a few months. In the present study, rotation of two hyperaccumulators is proposed to address this issue. An 18-month field experiment was conducted to evaluate the phytoextraction efficiency of Cd by the monoculture and rotation of Celosia argentea and Sedum plumbizincicola. The results showed that rotation increased amount of extracted Cd increased by 2.3 and 1.6 times compared with monoculture of C. argentea and S. plumbizincicola. In rotation system, the biomass of S. plumbizincicola and Cd accumulation in C. argentea increased by 54.4% and 40.7%, respectively. Rotation reduced fallow time and increased harvesting frequency, thereby enhancing Cd phytoextraction. Planting C. argentea significantly decreased soil pathogenic microbes and increased the abundances of plant growth-promoting rhizobacteria (PGPR) and 1-aminocyclopropane-1-carboxylate (ACC) deaminase genes, which may be beneficial for the growth of S. plumbizincicola. Planting S. plumbizincicola increased the abundance of sulfur oxidization (SOX) system genes and decreased soil pH (p < 0.05), thereby increasing the Cd uptake by C. argentea. These findings indicated that rotation of C. argentea and S. plumbizincicola is a promising method for promoting Cd phytoextraction.


Assuntos
Biodegradação Ambiental , Cádmio , Celosia , Sedum , Poluentes do Solo , Cádmio/metabolismo , Sedum/metabolismo , Sedum/crescimento & desenvolvimento , Poluentes do Solo/metabolismo , Celosia/metabolismo , Microbiologia do Solo , Agricultura , Biomassa
18.
J Am Chem Soc ; 146(21): 14889-14897, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38747066

RESUMO

Ni-rich cathodes are some of the most promising candidates for advanced lithium-ion batteries, but their available capacities have been stagnant due to the intrinsic Li+ storage sites. Extending the voltage window down can induce the phase transition from O3 to 1T of LiNiO2-derived cathodes to accommodate excess Li+ and dramatically increase the capacity. By setting the discharge cutoff voltage of LiNi0.6Co0.2Mn0.2O2 to 1.4 V, we can reach an extremely high capacity of 393 mAh g-1 and an energy density of 1070 Wh kg-1 here. However, the phase transition causes fast capacity decay and related structural evolution is rarely understood, hindering the utilization of this feature. We find that the overlithiated phase transition is self-limiting, which will transform into solid-solution reaction with cycling and make the cathode degradation slow down. This is attributed to the migration of abundant transition metal ions into lithium layers induced by the overlithiation, allowing the intercalation of overstoichiometric Li+ into the crystal without the O3 framework change. Based on this, the wide-potential cycling stability is further improved via a facile charge-discharge protocol. This work provides deep insight into the overstoichiometric Li+ storage behaviors in conventional layered cathodes and opens a new avenue toward high-energy batteries.

19.
Appl Microbiol Biotechnol ; 108(1): 320, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709366

RESUMO

The unspecific peroxygenase (UPO) from Cyclocybe aegerita (AaeUPO) can selectively oxidize C-H bonds using hydrogen peroxide as an oxygen donor without cofactors, which has drawn significant industrial attention. Many studies have made efforts to enhance the overall activity of AaeUPO expressed in Komagataella phaffii by employing strategies such as enzyme-directed evolution, utilizing appropriate promoters, and screening secretion peptides. Building upon these previous studies, the objective of this study was to further enhance the expression of a mutant of AaeUPO with improved activity (PaDa-I) by increasing the gene copy number, co-expressing chaperones, and optimizing culture conditions. Our results demonstrated that a strain carrying approximately three copies of expression cassettes and co-expressing the protein disulfide isomerase showed an approximately 10.7-fold increase in volumetric enzyme activity, using the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) as the substrate. After optimizing the culture conditions, the volumetric enzyme activity of this strain further increased by approximately 48.7%, reaching 117.3 U/mL. Additionally, the purified catalytic domain of PaDa-I displayed regioselective hydroxylation of R-2-phenoxypropionic acid. The results of this study may facilitate the industrial application of UPOs. KEY POINTS: • The secretion of the catalytic domain of PaDa-I can be significantly enhanced through increasing gene copy numbers and co-expressing of protein disulfide isomerase. • After optimizing the culture conditions, the volumetric enzyme activity can reach 117.3 U/mL, using the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) as the substrate. • The R-2-phenoxypropionic acid can undergo the specific hydroxylation reaction catalyzed by catalytic domain of PaDa-I, resulting in the formation of R-2-(4-hydroxyphenoxy)propionic acid.


Assuntos
Oxigenases de Função Mista , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Oxigenases de Função Mista/química , Saccharomycetales/genética , Saccharomycetales/enzimologia , Saccharomycetales/metabolismo , Dosagem de Genes , Isomerases de Dissulfetos de Proteínas/genética , Isomerases de Dissulfetos de Proteínas/metabolismo , Expressão Gênica , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/química
20.
Drug Des Devel Ther ; 18: 1439-1457, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38707616

RESUMO

Background: Acteoside, an active ingredient found in various medicinal herbs, is effective in the treatment of diabetic kidney disease (DKD); however, the intrinsic pharmacological mechanism of action of acteoside in the treatment of DKD remains unclear. This study utilizes a combined approach of network pharmacology and experimental validation to investigate the potential molecular mechanism systematically. Methods: First, acteoside potential targets and DKD-associated targets were aggregated from public databases. Subsequently, utilizing protein-protein interaction (PPI) networks, alongside GO and KEGG pathway enrichment analyses, we established target-pathway networks to identify core potential therapeutic targets and pathways. Further, molecular docking facilitated the confirmation of interactions between acteoside and central targets. Finally, the conjectured molecular mechanisms of acteoside against DKD were verified through experimentation on unilateral nephrectomy combined with streptozotocin (STZ) rat model. The underlying downstream mechanisms were further investigated. Results: Network pharmacology identified 129 potential intersected targets of acteoside for DKD treatment, including targets such as AKT1, TNF, Casp3, MMP9, SRC, IGF1, EGFR, HRAS, CASP8, and MAPK8. Enrichment analyses indicated the PI3K-Akt, MAPK, Metabolic, and Relaxin signaling pathways could be involved in this therapeutic context. Molecular docking revealed high-affinity binding of acteoside to PIK3R1, AKT1, and NF-κB1. In vivo studies validated the therapeutic efficacy of acteoside, demonstrating reduced blood glucose levels, improved serum Scr and BUN levels, decreased 24-hour urinary total protein (P<0.05), alongside mitigated podocyte injury (P<0.05) and ameliorated renal pathological lesions. Furthermore, this finding indicates that acteoside inhibits the expression of pyroptosis markers NLRP3, Caspase-1, IL-1ß, and IL-18 through the modulation of the PI3K/AKT/NF-κB pathway. Conclusion: Acteoside demonstrates renoprotective effects in DKD by regulating the PI3K/AKT/NF-κB signaling pathway and alleviating pyroptosis. This study explores the pharmacological mechanism underlying acteoside's efficacy in DKD treatment, providing a foundation for further basic and clinical research.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Glucosídeos , Simulação de Acoplamento Molecular , Farmacologia em Rede , Fenóis , Polifenóis , Estreptozocina , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Animais , Ratos , Glucosídeos/farmacologia , Glucosídeos/química , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Masculino , Fenóis/farmacologia , Fenóis/química , Ratos Sprague-Dawley
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