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1.
Nature ; 592(7855): 551-557, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33883734

RESUMEN

Solid-state lithium (Li)-air batteries are recognized as a next-generation solution for energy storage to address the safety and electrochemical stability issues that are encountered in liquid battery systems1-4. However, conventional solid electrolytes are unsuitable for use in solid-state Li-air systems owing to their instability towards lithium metal and/or air, as well as the difficulty in constructing low-resistance interfaces5. Here we present an integrated solid-state Li-air battery that contains an ultrathin, high-ion-conductive lithium-ion-exchanged zeolite X (LiX) membrane as the sole solid electrolyte. This electrolyte is integrated with cast lithium as the anode and carbon nanotubes as the cathode using an in situ assembly strategy. Owing to the intrinsic chemical stability of the zeolite, degeneration of the electrolyte from the effects of lithium or air is effectively suppressed. The battery has a capacity of 12,020 milliamp hours per gram of carbon nanotubes, and has a cycle life of 149 cycles at a current density of 500 milliamps per gram and at a capacity of 1,000 milliamp hours per gram. This cycle life is greater than those of batteries based on lithium aluminium germanium phosphate (12 cycles) and organic electrolytes (102 cycles) under the same conditions. The electrochemical performance, flexibility and stability of zeolite-based Li-air batteries confer practical applicability that could extend to other energy-storage systems, such as Li-ion, Na-air and Na-ion batteries.

2.
Nucleic Acids Res ; 52(6): 2886-2903, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38142446

RESUMEN

Adjusting intracellular metabolic pathways and adopting suitable live state such as biofilms, are crucial for bacteria to survive environmental changes. Although substantial progress has been made in understanding how the histone-like nucleoid-structuring (H-NS) protein modulates the expression of the genes involved in biofilm formation, the precise modification that the H-NS protein undergoes to alter its DNA binding activity is still largely uncharacterized. This study revealed that acetylation of H-NS at Lys19 inhibits biofilm development in Shewanella oneidensis MR-1 by downregulating the expression of glutamine synthetase, a critical enzyme in glutamine synthesis. We further found that nitrogen starvation, a likely condition in biofilm development, induces deacetylation of H-NS and the trimerization of nitrogen assimilation regulator GlnB. The acetylated H-NS strain exhibits significantly lower cellular glutamine concentration, emphasizing the requirement of H-NS deacetylation in Shewanella biofilm development. Moreover, we discovered in vivo that the activation of glutamine biosynthesis pathway and the concurrent suppression of the arginine synthesis pathway during both pellicle and attached biofilms development, further suggesting the importance of fine tune nitrogen assimilation by H-NS acetylation in Shewanella. In summary, posttranslational modification of H-NS endows Shewanella with the ability to respond to environmental needs by adjusting the intracellular metabolism pathways.


Asunto(s)
Histonas , Shewanella , Acetilación , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biopelículas , Glutamina/genética , Histonas/metabolismo , Homeostasis , Procesamiento Proteico-Postraduccional , Shewanella/genética , Shewanella/metabolismo
3.
PLoS Pathog ; 19(6): e1011470, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37347782

RESUMEN

The study of carrier state phages challenged the canonical lytic-lysogenic binary, and carrier state appears to be ubiquitous and ecologically important. However, the mechanisms of the carrier state are not well elucidated due to the limited phage models. Herein, we reported phage HQ103, similar to Escherichia coli phage P2. In contrast to the temperate P2 phage, the HQ103 phage does not insert its genome into the bacterial chromosome and displays a dual behavior depending on the temperature. At 37°C, HQ103 lyses the host and forms clear plaques due to the truncation of repressor CI and mutation of promoter Pc. In contrast, HQ103 maintains a carrier state lifestyle with Y. pestis at an environmental temperature (21°C). Mechanistically, we found that the host-encoded histone-like nucleoid-structuring protein H-NS, which is highly expressed at 21°C to silence the Cox promoter Pe and inhibits the phage lytic cycle. Subsequently, the HQ103 carrier state Y. pestis could grow and co-exist with the phage in the soil at 21°C for one month. Thus, this study reveals a novel carrier state lifestyle of phage HQ103 due to the H-NS mediated xenogeneic silencing and demonstrates that the carrier state lifestyle could promote long-term phage-host coexist in nature.


Asunto(s)
Bacteriófagos , Yersinia pestis , Bacteriófagos/genética , Suelo , Portador Sano , Temperatura , Lisogenia
4.
Nature ; 566(7744): 368-372, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30692651

RESUMEN

The mechanical and electronic properties of two-dimensional materials make them promising for use in flexible electronics1-3. Their atomic thickness and large-scale synthesis capability could enable the development of 'smart skin'1,3-5, which could transform ordinary objects into an intelligent distributed sensor network6. However, although many important components of such a distributed electronic system have already been demonstrated (for example, transistors, sensors and memory devices based on two-dimensional materials1,2,4,7), an efficient, flexible and always-on energy-harvesting solution, which is indispensable for self-powered systems, is still missing. Electromagnetic radiation from Wi-Fi systems operating at 2.4 and 5.9 gigahertz8 is becoming increasingly ubiquitous and would be ideal to harvest for powering future distributed electronics. However, the high frequencies used for Wi-Fi communications have remained elusive to radiofrequency harvesters (that is, rectennas) made of flexible semiconductors owing to their limited transport properties9-12. Here we demonstrate an atomically thin and flexible rectenna based on a MoS2 semiconducting-metallic-phase heterojunction with a cutoff frequency of 10 gigahertz, which represents an improvement in speed of roughly one order of magnitude compared with current state-of-the-art flexible rectifiers9-12. This flexible MoS2-based rectifier operates up to the X-band8 (8 to 12 gigahertz) and covers most of the unlicensed industrial, scientific and medical radio band, including the Wi-Fi channels. By integrating the ultrafast MoS2 rectifier with a flexible Wi-Fi-band antenna, we fabricate a fully flexible and integrated rectenna that achieves wireless energy harvesting of electromagnetic radiation in the Wi-Fi band with zero external bias (battery-free). Moreover, our MoS2 rectifier acts as a flexible mixer, realizing frequency conversion beyond 10 gigahertz. This work provides a universal energy-harvesting building block that can be integrated with various flexible electronic systems.

5.
BMC Genomics ; 25(1): 50, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38212691

RESUMEN

BACKGROUND: Even though the Buyei are a recognised ethnic group in southwestern China, there hasn't been much work done on forensic population genetics, notably using mitochondrial DNA. The sequences and haplogroups of mitochondrial DNA control regions of the Buyei peoples were studied to provide support for the establishment of a reference database for forensic DNA analysis in East Asia. METHODS AND RESULTS: The mitochondrial DNA control region sequences of 200 Buyei individuals in Guizhou were investigated. The haplotype frequencies and haplogroup distribution of the Buyei nationality in Guizhou were calculated. At the same time, the paired Fst values of the study population and other populations around the world were computed, to explore their genetic polymorphism and population relationship. A total of 179 haplotypes were detected in the Buyei population, with frequencies of 0.005-0.015. All haplotypes were assigned to 89 different haplogroups. The haplotype diversity and random matching probability were 0.999283 and 0.0063, respectively. The paired Fst genetic distances and correlation p-values among the 54 populations revealed that the Guizhou Buyei was most closely related to the Henan Han and the Guizhou Miao, and closer to the Hazara population in Pakistan and the Chiang Mai population. CONCLUSIONS: The study of mitochondrial DNA based on the maternal genetic structure of the Buyei nationality in Guizhou will benefit the establishment of an East Asian forensic DNA reference database and provide a reference for anthropological research in the future.


Asunto(s)
ADN Mitocondrial , Polimorfismo Genético , Humanos , ADN Mitocondrial/genética , Genética de Población , Haplotipos , China , Repeticiones de Microsatélite , Filogenia
6.
J Am Chem Soc ; 146(5): 3373-3382, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38272666

RESUMEN

Reticular chemistry effectively yields porous structures with distinct topological lattices for a broad range of applications. Polyhedral oligomeric silsesquioxane (POSS)-based octatopic building blocks with a rare Oh symmetric configuration and attracting inorganic features have great potential for creating three-dimensional (3D) covalent organic frameworks (COFs) with new topologies. However, the intrinsic flexibility and intensive motion of cubane-type POSS molecules make the construction of 3D regular frameworks challenging. Herein, by fastening three or four POSS cores with per aromatic rigid linker from rational steric directions, we successfully developed serial crystalline 3D COFs with unpresented "the" and scu topologies. Both the experimental and theoretical results proved the formation of target 3D POSS-based COFs. The resultant hybrid networks with designable chemical skeletons and high surface areas maintain the superiorities of both the inorganic and organic components, such as their high compatibility with inorganic salts, abundant periodic electroactive sites, excellent thermal stability, and open multilevel nanochannels. Consequently, the polycubane COFs could serve as outstanding solid electrolytes with a high ionic conductivity of 1.23 × 10-4 S cm-1 and a lithium-ion transference number of 0.86 at room temperature. This work offers a pathway to generate ordered lattices with multiconnected flexible cube motifs and enrich the topologies of 3D COFs for potential applications.

7.
J Am Chem Soc ; 146(2): 1305-1317, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38169369

RESUMEN

Aprotic lithium-oxygen (Li-O2) batteries are considered to be a promising alternative option to lithium-ion batteries for high gravimetric energy storage devices. However, the sluggish electrochemical kinetics, the passivation, and the structural damage to the cathode caused by the solid discharge products have greatly hindered the practical application of Li-O2 batteries. Herein, the nonsolid-state discharge products of the off-stoichiometric Li1-xO2 in the electrolyte solutions are achieved by iridium (Ir) single-atom-based porous organic polymers (termed as Ir/AP-POP) as a homogeneous, soluble electrocatalyst for Li-O2 batteries. In particular, the numerous atomic active sites act as the main nucleation sites of O2-related discharge reactions, which are favorable to interacting with O2-/LiO2 intermediates in the electrolyte solutions, owing to the highly similar lattice-matching effect between the in situ-formed Ir3Li and LiO2, achieving a nonsolid LiO2 as the final discharge product in the electrolyte solutions for Li-O2 batteries. Consequently, the Li-O2 battery with a soluble Ir/AP-POP electrocatalyst exhibits an ultrahigh discharge capacity of 12.8 mAh, an ultralow overpotential of 0.03 V, and a long cyclic life of 700 h with the carbon cloth cathode. The manipulation of nonsolid discharge products in aprotic Li-O2 batteries breaks the traditional growth mode of Li2O2, bringing Li-O2 batteries closer to being a viable technology.

8.
Appl Environ Microbiol ; 90(4): e0009524, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38497640

RESUMEN

Horizontal gene transfer, facilitated by mobile genetic elements (MGEs), is an adaptive evolutionary process that contributes to the evolution of bacterial populations and infectious diseases. A variety of MGEs not only can integrate into the bacterial genome but also can survive or even replicate like plasmids in the cytoplasm, thus requiring precise and complete removal for studying their strategies in benefiting host cells. Existing methods for MGE removal, such as homologous recombination-based deletion and excisionase-based methods, have limitations in effectively eliminating certain MGEs. To overcome these limitations, we developed the Cas9-NE method, which combines the CRISPR/Cas9 system with the natural excision of MGEs. In this approach, a specialized single guide RNA (sgRNA) element is designed with a 20-nucleotide region that pairs with the MGE sequence. This sgRNA is expressed from a plasmid that also carries the Cas9 gene. By utilizing the Cas9-NE method, both the integrative and circular forms of MGEs can be precisely and completely eliminated through Cas9 cleavage, generating MGE-removed cells. We have successfully applied the Cas9-NE method to remove four representative MGEs, including plasmids, prophages, and genomic islands, from Vibrio strains. This new approach not only enables various investigations on MGEs but also has significant implications for the rapid generation of strains for commercial purposes.IMPORTANCEMobile genetic elements (MGEs) are of utmost importance for bacterial adaptation and pathogenicity, existing in various forms and multiple copies within bacterial cells. Integrated MGEs play dual roles in bacterial hosts, enhancing the fitness of the host by delivering cargo genes and potentially modifying the bacterial genome through the integration/excision process. This process can lead to alterations in promoters or coding sequences or even gene disruptions at integration sites, influencing the physiological functions of host bacteria. Here, we developed a new approach called Cas9-NE, allowing them to maintain the natural sequence changes associated with MGE excision. Cas9-NE allows the one-step removal of integrated and circular MGEs, addressing the challenge of eliminating various MGE forms efficiently. This approach simplifies MGE elimination in bacteria, expediting research on MGEs.


Asunto(s)
Sistemas CRISPR-Cas , ARN Guía de Sistemas CRISPR-Cas , Bacterias/genética , Islas Genómicas , Transferencia de Gen Horizontal , Plásmidos/genética , Secuencias Repetitivas Esparcidas
9.
Plant Physiol ; 192(1): 205-221, 2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-36756926

RESUMEN

Flowering time is one of the most important agronomic traits affecting the adaptation and yield of rice (Oryza sativa). Heading date 1 (Hd1) is a key factor in the photoperiodic control of flowering time. In this study, two basic helix-loop-helix (bHLH) transcription factors, Hd1 Binding Protein 1 (HBP1) and Partner of HBP1 (POH1) were identified as transcriptional regulators of Hd1. We generated knockout mutants of HBP1 and ectopically expressed transgenic lines of the two bHLH transcription factors and used these lines to investigate the roles of these two factors in regulating flowering time. HBP1 physically associated with POH1 forming homo- or heterodimers to perform their functions. Both HBP1 and POH1 bound directly to the cis-acting elements located in the promoter of Hd1 to activate its expression. CRISPR/Cas9-generated knockout mutations of HBP1, but not POH1 mutations, promoted earlier flowering time; conversely, HBP1 and POH1 overexpression delayed flowering time in rice under long-day and short-day conditions by activating the expression of Hd1 and suppressing the expression of Early heading date 1 (Ehd1), Heading date 3a (Hd3a), and Rice Flowering locus T 1 (RFT1), thus controlling flowering time in rice. Our findings revealed a mechanism for flowering time control through transcriptional regulation of Hd1 and laid theoretical and practical foundations for improving the growth period, adaptation, and yield of rice.


Asunto(s)
Flores , Oryza , Oryza/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Fotoperiodo , Fenotipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas
10.
Bioorg Chem ; 143: 107004, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38086238

RESUMEN

In this study, we identified a newly synthesized compound 7o with potent inhibition on EGFR primary mutants (L858R, Del19) and drug-resistant mutant T790M with nanomolar IC50 values. 7o showed strong antiproliferative effects against EGFR mutant-driven non-small cell lung cancer (NSCLC) cells such as H1975, PC-9 and HCC827, over cells expressing EGFRWT. Molecular docking was performed to investigate the possible binding modes of 7o inside the binding site of EGFRL858R/T790M and EGFRWT. Analysis of cell cycle evidenced that 7o induced cell cycle arrest in G1 phases in the EGFR mutant cells, H1975 and PC-9, which resulted in decreased S-phase populations. Moreover, compound 7o induced cancer cell apoptosis in in vitro assays. In addition, 7o inhibited cellular phosphorylation of EGFR. In vivo, oral administration of 7o caused rapid tumor regression in H1975 xenograft model. Therefore, 7o might deserve further optimization as cancer treatment agent for EGFR mutant-driven NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Receptores ErbB , Simulación del Acoplamiento Molecular , Proliferación Celular , Inhibidores de Proteínas Quinasas , Mutación , Línea Celular Tumoral , Resistencia a Antineoplásicos
11.
Cell Mol Biol Lett ; 29(1): 5, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172714

RESUMEN

BACKGROUND: The abnormality of chromosomal karyotype is one factor causing poor prognosis of lymphoma. In the analysis of abnormal karyotype of lymphoma patients, three smallest overlap regions were found, in which MYCT1 was located. MYCT1 is the first tumor suppressor gene cloned by our research team, but its studies relating to the occurrence and development of lymphoma have not been reported. METHODS: R banding analyses were employed to screen the abnormality of chromosomal karyotype in clinical specimen and MYCT1 over-expression cell lines. FISH was to monitor MYCT1 copy number aberration. RT-PCR and Western blot were to detect the mRNA and protein levels of the MYCT1 and RUNX1 genes, respectively. The MYCT1 and RUNX1 protein levels in clinical specimen were evaluated by immunohistochemical DAB staining. The interaction between MYCT1 and MAX proteins was identified via Co-IP and IF. The binding of MAX on the promoter of the RUNX1 gene was detected by ChIP and Dual-luciferase reporter assay, respectively. Flow cytometry and CCK-8 assay were to explore the effects of MYCT1 and RUNX1 on the cell cycle and proliferation, respectively. RESULTS: MYCT1 was located in one of three smallest overlap regions of diffuse large B-cell lymphoma, it altered chromosomal instability of diffuse large B-cell lymphoma cells. MYCT1 negatively correlated with RUNX1 in lymphoma tissues of the patients. MAX directly promoted the RUNX1 gene transcription by binding to its promoter region. MYCT1 may represses RUNX1 transcription by binding MAX in diffuse large B-cell lymphoma cells. MYCT1 binding to MAX probably suppressed RUNX1 transcription, leading to the inhibition of proliferation and cell cycle of the diffuse large B-cell lymphoma cells. CONCLUSION: This study finds that there is a MYCT1-MAX-RUNX1 signaling pathway in diffuse large B-cell lymphoma. And the study provides clues and basis for the in-depth studies of MYCT1 in the diagnosis, treatment and prognosis of lymphoma.


Asunto(s)
Subunidad alfa 2 del Factor de Unión al Sitio Principal , Linfoma de Células B Grandes Difuso , Humanos , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 2 del Factor de Unión al Sitio Principal/metabolismo , Regiones Promotoras Genéticas , Linfoma de Células B Grandes Difuso/genética , Hematopoyesis , Línea Celular Tumoral , Proteínas Nucleares/metabolismo
12.
BMC Public Health ; 24(1): 1074, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38632558

RESUMEN

BACKGROUND: The prevalence of hyperuricemia in China has been consistently increasing, particularly among the younger generation. The excessive consumption of sugar-sweetened beverages is associated with hyperuricemia. This study examined the knowledge, attitudes, and practices (KAP) of Chinese young adults regarding sugar-sweetened beverage consumption and the correlation with hyperuricemia. METHODS: This cross-sectional investigation was conducted from June 28th, 2023, to July 21st, 2023, and enrolled Chinese young adults. Demographics and KAP were evaluated using a questionnaire (Cronbach's α = 0.787). Factors influencing KAP scores were analyzed using multivariable analyses. RESULTS: A total of 1288 valid questionnaires were analyzed. The median knowledge, attitude, and practice scores were 16 (12,19)/22, 22 (20,24)/30, and 27.5 (23,31.75)/40. The multivariable analysis showed that bachelor's/associate education (OR = 1.912, 95%CI: 1.128-3.239), white collar/employee (OR = 0.147, 95%CI: 0.105-0.206), educator (OR = 0.300, 95%CI: 0.174-0.518), healthcare worker (OR = 0.277, 95%CI: 0.188-0.407), not suffering from hyperuricemia (OR = 0.386, 95%CI: 0.253-0.590), and not having gout (OR = 0.456, 95%CI: 0.282-0.736) were independently associated with knowledge. Age 26-30 (OR = 1.470, 95%CI: 1.052-2.052), age 31-35 (OR = 1.489, 95%CI: 1.097-2.022), age 36-40 (OR = 0.328, 95%CI: 1.010-1.746), age 41-44 (OR = 1.548, 95%CI: 1.091-2.198), and not having hyperuricemia (OR = 0.512, 95%CI: 0.345-0.760) were independently associated with attitude. White collar/employee (OR = 0.386, 95%CI: 0.285-0.521), educator (OR = 0.534, 95%CI: 0.317-0.899), healthcare worker (OR = 0.341, 95%CI: 0.236-0.493), having siblings (OR = 0.725, 95%CI: 0.573-0.917), and not suffering from hyperuricemia (OR = 0.442, 95%CI: 0.296-0.659), were independently associated with practice. CONCLUSION: Chinese young adults display moderate KAP toward sugar-sweetened beverages. Notably, an association was observed between hyperuricemia and each KAP dimension.


Asunto(s)
Hiperuricemia , Bebidas Azucaradas , Humanos , Adulto Joven , Adulto , Hiperuricemia/epidemiología , Estudios Transversales , Encuestas y Cuestionarios , China , Bebidas
13.
Proc Natl Acad Sci U S A ; 118(4)2021 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-33483419

RESUMEN

Toxin-antitoxin (TA) loci were initially identified on conjugative plasmids, and one function of plasmid-encoded TA systems is to stabilize plasmids or increase plasmid competition via postsegregational killing. Here, we discovered that the type II TA system, Pseudoalteromonas rubra plasmid toxin-antitoxin PrpT/PrpA, on a low-copy-number conjugative plasmid, directly controls plasmid replication. Toxin PrpT resembles ParE of plasmid RK2 while antitoxin PrpA (PF03693) shares no similarity with previously characterized antitoxins. Surprisingly, deleting this prpA-prpT operon from the plasmid does not result in plasmid segregational loss, but greatly increases plasmid copy number. Mechanistically, the antitoxin PrpA functions as a negative regulator of plasmid replication, by binding to the iterons in the plasmid origin that inhibits the binding of the replication initiator to the iterons. We also demonstrated that PrpA is produced at a higher level than PrpT to prevent the plasmid from overreplicating, while partial or complete degradation of labile PrpA derepresses plasmid replication. Importantly, the PrpT/PrpA TA system is conserved and is widespread on many conjugative plasmids. Altogether, we discovered a function of a plasmid-encoded TA system that provides new insights into the physiological significance of TA systems.


Asunto(s)
Replicación del ADN/genética , Plásmidos/genética , Pseudoalteromonas/genética , Sistemas Toxina-Antitoxina/genética , Proteínas Bacterianas/genética , Toxinas Bacterianas/genética , Variaciones en el Número de Copia de ADN/genética , Topoisomerasa de ADN IV/genética , Escherichia coli/genética
14.
Angew Chem Int Ed Engl ; 63(11): e202319211, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38198190

RESUMEN

Li-N2 batteries have received widespread attention for their potential to integrate N2 fixation, energy storage, and conversion. However, because of the low activity and poor stability of cathode catalysts, the electrochemical performance of Li-N2 batteries is suboptimal, and their electrochemical reversibility has rarely been proven. In this study, a novel bifunctional photo-assisted Li-N2 battery system was established by employing a plasmonic Au nanoparticles (NPs)-modified defective carbon nitride (Au-Nv -C3 N4 ) photocathode. The Au-Nv -C3 N4 exhibits strong light-harvesting, N2 adsorption, and N2 activation abilities, and the photogenerated electrons and hot electrons are remarkably beneficial for accelerating the discharge and charge reaction kinetics. These advantages enable the photo-assisted Li-N2 battery to achieve a low overpotential of 1.32 V, which is the lowest overpotential reported to date, as well as superior rate capability and prolonged cycle stability (≈500 h). Remarkably, a combination of theoretical and experimental results demonstrates the high reversibility of the photo-assisted Li-N2 battery. The proposed novel strategy for developing efficient cathode catalysts and fabricating photo-assisted battery systems breaks through the overpotential bottleneck of Li-N2 batteries, providing important insights into the mechanism underlying N2 fixation and storage.

15.
Angew Chem Int Ed Engl ; 63(5): e202317949, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38078904

RESUMEN

Solid-state lithium (Li) batteries promise both high energy density and safety while existing solid-state electrolytes (SSEs) fail to satisfy the rigorous requirements of battery operations. Herein, novel polyoxometalate SSEs, Li3 PW12 O40 and Li3 PMo12 O40 , are synthesized, which exhibit excellent interfacial compatibility with electrodes and chemical stability, overcoming the limitations of conventional SSEs. A high ionic conductivity of 0.89 mS cm-1 and a low activation energy of 0.23 eV are obtained due to the optimized three-dimensional Li+ migration network of Li3 PW12 O40 . Li3 PW12 O40 exhibits a wide window of electrochemical stability that can both accommodate the Li anode and high-voltage cathodes. As a result, all-solid-state Li metal batteries fabricated with Li/Li3 PW12 O40 /LiNi0.5 Co0.2 Mn0.3 O2 display a stable cycling up to 100 cycles with a cutoff voltage of 4.35 V and an areal capacity of more than 4 mAh cm-2 , as well as a cost-competitive SSEs price of $5.68 kg-1 . Moreover, Li3 PMo12 O40 homologous to Li3 PW12 O40 was obtained via isomorphous substitution, which formed a low-resistance interface with Li3 PW12 O40 . Applications of Li3 PW12 O40 and Li3 PMo12 O40 in Li-air batteries further demonstrate that long cycle life (650 cycles) can be achieved. This strategy provides a facile, low-cost strategy to construct efficient and scalable solid polyoxometalate electrolytes for high-energy solid-state Li metal batteries.

16.
J Am Chem Soc ; 145(10): 5718-5729, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36880105

RESUMEN

The demand for high-energy sustainable rechargeable batteries has motivated the development of lithium-oxygen (Li-O2) batteries. However, the inherent safety issues of liquid electrolytes and the sluggish reaction kinetics of existing cathodes remain fundamental challenges. Herein, we demonstrate a promising photo-assisted solid-state Li-O2 battery based on metal-organic framework-derived mixed ionic/electronic conductors, which simultaneously serve as the solid-state electrolytes (SSEs) and the cathode. The mixed conductors could effectively harvest ultraviolet-visible light to generate numerous photoelectrons and holes, which is favorable to participate in the electrochemical reaction, contributing to greatly improved reaction kinetics. According to the study on conduction behavior, we discover that the mixed conductors as SSEs possess outstanding Li+ conductivity (1.52 × 10-4 S cm-1 at 25 °C) and superior chemical/electrochemical stability (especially toward H2O, O2-, etc.). Application of mixed ionic electronic conductors in photo-assisted solid-state Li-O2 batteries further reveals that a high energy efficiency (94.2%) and a long life (320 cycles) can be achieved with a simultaneous design of SSEs and cathodes. The achievements present the widespread universality in accelerating the development of safe and high-performance solid-state batteries.

17.
Anal Chem ; 95(2): 1065-1073, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36542087

RESUMEN

Protein aggregation has been found in a wide range of neurodegenerative protein-misfolding diseases. The demand for in vivo technologies to identify protein aggregation is at the leading edge for the pathogenic study, diagnostic development, and therapeutic intervention of these devastating disorders. Herein, we report a series of luminol analogues to construct a facile chemiluminescence (CL)-based approach for in vivo detection and imaging of ß-sheet protein aggregates. The synthesized compounds exhibited a distinct chemiluminescent response with long emission wavelengths toward reactive oxygen species under physiological conditions and displayed signal amplification in the presence of ß-sheet protein aggregates, including α-synuclein, ß-amyloid, and tau. Among them, CyLumi-3 was further evaluated as a chemiluminescent probe in preclinical models. By intravenous administration into the model mice via the tail vein, in vivo CL imaging noninvasively detected the specific CL of the probe targeting the α-synuclein aggregates in the brains of living mice. Based on its structural characteristics, CyLumi-3 can readily interact with α-synuclein aggregates with significantly enhanced fluorescence and can identify α-synuclein aggregates in vivo via distinctive CL amplification, which could pave the way for a more comprehensive understanding of protein aggregation in preclinical studies and would provide new hints for developing small-molecule chemiluminophores for protein aggregates.


Asunto(s)
Agregado de Proteínas , alfa-Sinucleína , Animales , Ratones , alfa-Sinucleína/química , Luminol/química , Conformación Proteica en Lámina beta , Especies Reactivas de Oxígeno/metabolismo , Técnicas Biosensibles/métodos
18.
Metab Eng ; 79: 86-96, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37451534

RESUMEN

Approaches to improve plasmid-mediated transgene expression are needed for gene therapy and genetic immunization applications. The backbone sequences needed for the production of plasmids in bacterial hosts and the use of antibiotic resistance genes as selection markers represent biological safety risks. Here, we report the development of an antibiotic-free expression plasmid vector with a minimized backbone utilizing a new toxin-antitoxin (TA) system. The Rs_0636/Rs_0637 TA pair was derived from the coral-associated bacterium Roseivirga sp. The toxin gene is integrated into the chromosome of Escherichia coli host cells, and a recombinant mammalian expression plasmid is constructed by replacing the antibiotic resistance gene with the antitoxin gene Rs_0637 (here named Tiniplasmid). The Tiniplasmid system affords high selection efficiency (∼80%) for target gene insertion into the plasmid and has high plasmid stability in E. coli (at least 9 days) in antibiotic-free conditions. Furthermore, with the aim of reducing the size of the backbone sequence, we found that the antitoxin gene can be reduced to 153 bp without a significant reduction in selection efficiency. To develop its applications in gene therapy and DNA vaccines, the biosafety and efficiency of the Tiniplasmid-based eukaryotic gene delivery and expression were further evaluated in CHO-K1 cells. The results showed that Rs_0636/Rs_0637 has no cell toxicity and that the Tiniplasmid vector has a higher gene expression efficiency than the commercial vectors pCpGfree and pSTD in the eukaryotic cells. Altogether, the results demonstrate the potential of the Rs_0636/Rs_0637-based antibiotic-free plasmid vector for the development and production of safe and efficacious DNA vaccines.


Asunto(s)
Antitoxinas , Sistemas Toxina-Antitoxina , Vacunas de ADN , Animales , Escherichia coli/metabolismo , Antibacterianos , Sistemas Toxina-Antitoxina/genética , Vacunas de ADN/genética , Plásmidos/genética , Antitoxinas/genética , Antitoxinas/metabolismo , Terapia Genética , Mamíferos/genética , Mamíferos/metabolismo
19.
Chemistry ; 29(53): e202301722, 2023 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-37382478

RESUMEN

Graphynes (GYs) are a novel type of carbon allotrope composed of sp and sp2 hybridized carbon atoms, boasting both a planar conjugated structure akin to graphene and a pore-like configuration in three-dimensional space. Graphdiyne (GDY), the first successfully synthesized member of GYs family, has gained much interest due to its fascinating electrochemical properties including a greater theoretical capacity, high charge mobility and advanced electronic transport properties, making it a promising material for energy storage applications for lithium-ion and hydrogen storage. Various methods, including heteroatom substitution, embedding, strain, and nanomorphology control, have been employed to further enhance the energy storage performance of GDY. Despite the potential of GDY in energy storage applications, there are still challenges to overcome in scaling up mass production. This review summarizes recent progress in the synthesis and application of GDY in lithium-ion and hydrogen storage, highlighting the obstacles faced in large-scale commercial application of GDY-based energy storage devices. Suggestions on possible solutions to overcome these hurdles have also been provided. Overall, the unique properties of GDY make it a promising material for energy storage applications in lithium-ion and hydrogen storage devices. The findings presented here will inspire further development of energy storage devices utilizing GDY.

20.
J Muscle Res Cell Motil ; 44(4): 311-323, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37889396

RESUMEN

This study aimed to explore the occurrence of necroptosis in skeletal muscle after eccentric exercise and investigate the role and possible mechanisms of ZBP1 and its related pathway proteins in the process, providing a theoretical basis for the study of exercise-induced skeletal muscle injury and recovery. Forty-eight male adult Sprague-Dawley rats were randomly divided into a control group (C, n = 8) and an exercise group (E, n = 40). The exercise group was further divided into 0 h (E0), 12 h (E12), 24 h (E24), 48 h (E48), and 72 h (E72) after exercise, with 8 rats in each subgroup. At each time point, gastrocnemius muscle was collected under general anesthesia. The expression levels of ZBP1 and its related pathway proteins were assessed using Western blot analysis. The colocalization of pathway proteins was examined using immunofluorescence staining. After 48 h of eccentric exercise, the expression of necroptosis marker protein MLKL reached its peak (P < 0.01), and the protein levels of ZBP1, RIPK3, and HMGB1 also peaked (P < 0.01). At 48 h post high-load eccentric exercise, there was a significant increase in colocalization of ZBP1/RIPK3 pathway proteins, reaching a peak (P < 0.01). (1) Eccentric exercise induced necroptosis in skeletal muscle, with MLKL, p-MLKLS358, and HMGB1 significantly elevated, especially at 48 h after exercise. (2) After eccentric exercise, the ZBP1/RIPK3-related pathway proteins ZBP1, RIPK3, and p-RIPK3S232 were significantly elevated, particularly at 48 h after exercise. (3) Following high-load eccentric exercise, there was a significant increase in the colocalization of ZBP1/RIPK3 pathway proteins, with a particularly pronounced elevation observed at 48 h post-exercise.


Asunto(s)
Proteína HMGB1 , Proteínas Quinasas , Animales , Masculino , Ratas , Músculo Esquelético/metabolismo , Necroptosis , Proteínas Quinasas/metabolismo , Ratas Sprague-Dawley
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