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1.
ACS Nanosci Au ; 4(2): 128-135, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38644965

RESUMO

Surface-catalyzed reactions have been used to synthesize carbon nanomaterials with atomically predefined structures. The recent discovery of a gold surface-catalyzed [3 + 3] cycloaromatization of isopropyl substituted arenes has enabled the on-surface synthesis of arylene-phenylene copolymers, where the surface activates the isopropyl substituents to form phenylene rings by intermolecular coupling. However, the resulting polymers suffered from undesired cross-linking when more than two molecules reacted at a single site. Here we show that such cross-links can be prevented through steric protection by attaching the isopropyl groups to larger arene cores. Upon thermal activation of isopropyl-substituted 8,9-dioxa-8a-borabenzo[fg]tetracene on Au(111), cycloaromatization is observed to occur exclusively between the two molecules. The cycloaromatization intermediate formed by the covalent linking of two molecules is prevented from reacting with further molecules by the wide benzotetracene core, resulting in highly selective one-to-one coupling. Our findings extend the versatility of the [3 + 3] cycloaromatization of isopropyl substituents and point toward steric protection as a powerful concept for suppressing competing reaction pathways in on-surface synthesis.

2.
Small ; : e2311914, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566542

RESUMO

The high-performance hole transporting material (HTM) is one of the most important components for the perovskite solar cells (PSCs) in promoting power conversion efficiency (PCE). However, the low conductivity of HTMs and their additional requirements for doping and post-oxidation greatly limits the device performance. In this work, three novel pyrene-based derivatives containing methoxy-substituted triphenylamines units (PyTPA, PyTPA-OH and PyTPA-2OH) are designed and synthesized, where different numbers of hydroxyl groups are connected at the 2- or 2,7-positions of the pyrene core. These hydroxyl groups at the 2- or 2,7-positions of pyrene play a significantly role to enhance the intermolecular interactions that are able to generate in situ radicals with the assistance of visible light irradiation, resulting in enhanced hole transferring ability, as well as an enhanced conductivity and suppressed recombination. These pyrene-core based HTMs exhibit excellent performance in PSCs, which possess a higher PCE than those control devices using the traditional spiro-OMeTAD as the HTM. The best performance can be found in the devices with PyTPA-2OH. It has an average PCE of 23.44% (PCEmax = 23.50%), which is the highest PCE among the reported PSCs with the pyrene-core based HTMs up to date. This research offers a novel avenue to design a dopant-free HTM by the combination of the pyrene core, methoxy triphenylamines, and hydroxy groups.

3.
Sci Adv ; 10(11): eadl4871, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489356

RESUMO

Noise-enhanced applications in open quantum walk (QW) has recently seen a surge due to their ability to improve performance. However, verifying the success of open QW is challenging, as mixed-state tomography is a resource-intensive process, and implementing all required measurements is almost impossible due to various physical constraints. To address this challenge, we present a neural-network-based method for reconstructing mixed states with a high fidelity (∼97.5%) while costing only 50% of the number of measurements typically required for open discrete-time QW in one dimension. Our method uses a neural density operator that models the system and environment, followed by a generalized natural gradient descent procedure that significantly speeds up the training process. Moreover, we introduce a compact interferometric measurement device, improving the scalability of our photonic QW setup that enables experimental learning of mixed states. Our results demonstrate that highly expressive neural networks can serve as powerful alternatives to traditional state tomography.

4.
Nat Commun ; 15(1): 2684, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538576

RESUMO

It is a long-standing scientific controversy to achieve anti-Kasha-type multiple emissions by tuning the structures at a molecular level. Although it is known that some conjugated structures have excitation-dependent multiple emissions, no all-benzenoid molecules have yet been reported, the emissions of which originate from different excited states. Herein, we report the design of two symmetry-breaking heterogeneous carbon bisnanohoops that in solution become multiple fluorescent emitters with unusual anti-Kasha characteristics. This phenomenon can be spectroscopically and theoretically explained and will find applications in a wide range of sensing and imaging technologies.

5.
ACS Appl Mater Interfaces ; 16(11): 13927-13937, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38456299

RESUMO

Two-dimensional van der Waals (2D vdW) heterostructure photodetectors have garnered significant attention for their potential applications in next-generation optoelectronic systems. However, current 2D vdW photodetectors inevitably encounter compromises between responsivity, detectivity, and response time due to the absence of multilevel regulation for free and photoexcited carriers, thereby restricting their widespread applications. To address this challenge, we propose an efficient 2D WS2/CuInP2S6 vdW heterostructure photodetector by combining band engineering and ferroelectric modulation. In this device, the asymmetric conduction and valence band offsets effectively block the majority carriers (free electrons), while photoexcited holes are efficiently tunneled and rapidly collected by the bottom electrode. Additionally, the ferroelectric CuInP2S6 layer generates polarization states that reconfigure the built-in electric field, reducing dark current and facilitating the separation of photocarriers. Moreover, photoelectrons are trapped during long-distance lateral transport, resulting in a high photoconductivity gain. Consequently, the device achieves an impressive responsivity of 88 A W-1, an outstanding specific detectivity of 3.4 × 1013 Jones, and a fast response time of 37.6/371.3 µs. Moreover, the capability of high-resolution imaging under various wavelengths and fast optical communication has been successfully demonstrated using this device, highlighting its promising application prospects in future optoelectronic systems.

6.
ACS Omega ; 9(8): 9720-9727, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38434812

RESUMO

An inverse opal structure of SnO2 with a honeycomb morphology is introduced as the framework for the attached perovskite materials and functional layers in the hybrid perovskite-based solar cells simultaneously. Three different pore sizes of polystyrene microsphere layers, with diameters of 350, 480, and 600 nm, were fabricated through a vertical self-assembly vaporization technique. The polystyrene (PS) layer served as the sacrificial template for the inverse opal structure. By controlling the spinning parameters, the inverse opal-structured SnO2 layer was used to constrain them into a single-layer stacking structure. These layers with varying pore sizes were subsequently applied onto a dense electron transport layer that is in contact with the perovskite layer. A carbon electrode is used as photovoltaic solar cells. The major benefits of this approach were systematically analyzed through structural characterizations and various means. The semiphotonic crystal layer induces modulation effects, resulting in increased light absorption and surface area, which leads to a substantial increase in short-circuit density. By studying the electrochemical properties in the dark to exclude the influence of optical effects, we attribute the slight increase in the fill factor to the increased surface area, which enhances carrier transport. Among the different layers, the inverse opal layer prepared with 480 nm polystyrene microspheres displayed superior photovoltaic performance parameters due to its appropriate surface area and relatively higher light absorption. The power conversion efficiency of the MAPbI3 perovskite solar cell showed a relative enhancement of 55%. Additionally, aging tests demonstrated that devices with the additional structural layer exhibited good endurance under conventional atmospheric conditions after 1440 h of aging.

7.
JCI Insight ; 9(4)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38385749

RESUMO

RNA-binding proteins (RBPs) interact with RNA and ubiquitously regulate RNA transcripts during their life cycle, playing a fundamental role in the progression of angiogenesis-related diseases. In the skeletal system, endothelium-dependent angiogenesis is indispensable for bone formation. However, the role of RBPs in endothelium-dependent bone formation is unclear. Here, we show that RBP-Y-box-binding protein 1 (YBX1) was strongly reduced in the bone vasculature of ovariectomy (OVX) mice. Endothelial cell-specific deletion of Ybx1 impaired CD31-high, endomucin-high (CD31hiEMCNhi) endothelium morphology and resulted in low bone mass whereas Ybx1 overexpression promoted angiogenesis-dependent osteogenesis and ameliorated bone loss. Mechanistically, YBX1 deletion disrupted CD31, EMCN, and bone morphogenetic protein 4 (BMP4) stability in an m5C-dependent manner and blocked endothelium-derived BMP4 release, thereby inhibiting osteogenic differentiation of bone mesenchymal stromal cells. Administration of recombinant BMP4 protein restored impaired bone formation in Ybx1 deletion mice. Tail vein injection of CD31-modified polyethylene glycol-poly (lactic-co-glycolic acid) carrying sciadopitysin, a natural YBX1 agonist, pharmacologically partially reversed CD31hiEMCNhi vessels' decline and improved bone mass in both OVX and aging animals. These findings demonstrated the role of RBP-YBX1 in angiogenesis-dependent bone formation and provided a therapeutic approach for ameliorating osteoporosis.


Assuntos
Osteogênese , Osteoporose , Fatores de Transcrição , Animais , Feminino , Camundongos , Osso e Ossos/metabolismo , Endotélio/metabolismo , Osteogênese/fisiologia , Osteoporose/genética , RNA , Fatores de Transcrição/genética
8.
Front Med (Lausanne) ; 11: 1268008, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38384406

RESUMO

Bronchopulmonary foregut malformation (BPFM) is a rare developmental malformation disease due to embryonic defects, with an even rarer occurrence in adults. We report a diagnosed case in an adult patient, and notably, this is the first reported case of such advanced age. Additionally, she experienced coughing up approximately 1 liter of blood and partial lung tissue, accompanied by respiratory failure and shock. Following treatment with transcatheter arterial embolization, her condition improved, and she has remained stable during follow-up. We present a case report and conducted a systematic review on this particular case.

10.
Angew Chem Int Ed Engl ; 63(11): e202316596, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38216533

RESUMO

Embedding both boron and nitrogen into the backbone of acenes to generate their isoelectronic structures has significantly enriched the acene chemistry to offer appealing properties. However, only small BN-heteroacenes have been extensively investigated, with BN-heptacenes as the hitherto longest homologue. Herein, we report the synthesis of three new nonacene BN-isosteres via incorporating a pair of antiaromatic B2 C4 and N2 C4 heterocycles, representing a new length record for BN-heteroacenes. The distance between the B2 C4 and N2 C4 rings affects the contribution of the charge-separated resonance forms, leading to tunable antiaromaticity of the two heterocycles. The adjusted local antiaromaticity manifests substantial influence on the molecular orbital arrangement, and consequently, the radiative transition rate of BN-3 is greatly enhanced compared with BN-1 and BN-2, realizing a high fluorescence quantum yield of 92 %. This work provides a novel design concept of large acene BN-isosteres and reveals the importance of BN/CC isosterism on their luminescent properties.

11.
Bone Res ; 12(1): 6, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38267422

RESUMO

Skeletal stem/progenitor cell (SSPC) senescence is a major cause of decreased bone regenerative potential with aging, but the causes of SSPC senescence remain unclear. In this study, we revealed that macrophages in calluses secrete prosenescent factors, including grancalcin (GCA), during aging, which triggers SSPC senescence and impairs fracture healing. Local injection of human rGCA in young mice induced SSPC senescence and delayed fracture repair. Genetic deletion of Gca in monocytes/macrophages was sufficient to rejuvenate fracture repair in aged mice and alleviate SSPC senescence. Mechanistically, GCA binds to the plexin-B2 receptor and activates Arg2-mediated mitochondrial dysfunction, resulting in cellular senescence. Depletion of Plxnb2 in SSPCs impaired fracture healing. Administration of GCA-neutralizing antibody enhanced fracture healing in aged mice. Thus, our study revealed that senescent macrophages within calluses secrete GCA to trigger SSPC secondary senescence, and GCA neutralization represents a promising therapy for nonunion or delayed union in elderly individuals.


Assuntos
Calosidades , Fraturas Ósseas , Idoso , Humanos , Animais , Camundongos , Consolidação da Fratura , Senescência Celular , Envelhecimento , Macrófagos , Células-Tronco
12.
Nat Protoc ; 19(4): 1252-1287, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38253658

RESUMO

N6-methyladenosine (m6A) is the most abundant posttranscriptional chemical modification in mRNA, involved in regulating various physiological and pathological processes throughout mRNA metabolism. Recently, we developed GLORI, a sequencing method that enables the production of a globally absolute-quantitative m6A map at single-base resolution. Our technique utilizes the glyoxal- and nitrite-based chemical reaction, which selectively deaminates unmethylated adenosines while leaving m6A intact. The RNA library can then be prepared using a modified library construction protocol from enhanced UV crosslinking and immunoprecipitation (eCLIP) or commercial kits. Here we provide a detailed protocol for proper RNA sample handling and provide further guidelines for the use of a tailored bioinformatics pipeline (GLORI-tools) for subsequent data analysis. Compared with current methods, this new method is both exceptionally sensitive and robust, capable of identifying ~80,000 m6A sites with 50 Gb sequencing data in mammalian cells. It also provides a quantitative readout for m6A sites at single-base resolution. We hope the technique will provide a precise and unbiased tool for investigating m6A biology across various fields. Basic expertise in molecular biology and knowledge of bioinformatics are required for the protocol. The entire procedure can be completed within a week, with the library construction process taking ~4 d.


Assuntos
RNA , Transcriptoma , Animais , RNA/genética , RNA Mensageiro/metabolismo , Metilação , Biblioteca Gênica , Mamíferos/genética
13.
J Multidiscip Healthc ; 17: 111-121, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38205129

RESUMO

Objective: To understand the status of media exposure, social support, self-efficacy, and health literacy among middle-aged and older adults in China, and explore the impact path of media exposure on the health literacy of this population, providing a reference for promoting their physical and mental health. Methods: From July to November 2022, a multi-stage random sampling method was employed to survey 16,938 Chinese middle-aged and older adults aged 46 and above. Structural equation modeling and statistical analysis were conducted using LISREL 8.8 and Mplus 8.3 software. Results: The average score for media exposure among Chinese middle-aged and older adults was (18.55±5.36), perceived social support was (60.68±12.51), self-efficacy was (28.76±5.40), and health literacy was (35.49±6.05). Statistical results revealed that media exposure has a positive impact on the health literacy of middle-aged and older adults, with a direct effect of 0.091 (p < 0.001). Mediation analysis showed that media exposure can affect the health literacy of this population through the independent mediating effects of perceived social support (ß = 0.013, p < 0.001) and self-efficacy (ß = 0.029, p < 0.001), as well as through a chain mediation effect involving perceived social support and self-efficacy (ß = 0.015, p < 0.001). Conclusion: As a pathway for health information dissemination, media exposure plays a crucial role in the intervention of health literacy among middle-aged and older adults. Perceived social support and self-efficacy not only have independent mediating effects but also significant chain mediating effects in the relationship between media exposure and health literacy among this population. Therefore, improving the health literacy of middle-aged and older people can be popularized through media and improved in a multi-path, all-round, and precise way with the help of related technologies and social forces from which media literacy can be improved.

14.
Nat Commun ; 15(1): 97, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167327

RESUMO

The crosstalk between the bone and adipose tissue is known to orchestrate metabolic homeostasis, but the underlying mechanisms are largely unknown. Herein, we find that GCA + (grancalcin) immune cells accumulate in the bone marrow and release a considerable amount of GCA into circulation during obesity. Genetic deletion of Gca in myeloid cells attenuates metabolic dysfunction in obese male mice, whereas injection of recombinant GCA into male mice causes adipose tissue inflammation and insulin resistance. Mechanistically, we found that GCA binds to the Prohibitin-2 (PHB2) receptor on adipocytes and activates the innate and adaptive immune response of adipocytes via the PAK1-NF-κB signaling pathway, thus provoking the infiltration of inflammatory immune cells. Moreover, we show that GCA-neutralizing antibodies improve adipose tissue inflammation and insulin sensitivity in obese male mice. Together, these observations define a mechanism whereby bone marrow factor GCA initiates adipose tissue inflammation and insulin resistance, showing that GCA could be a potential target to treat metainflammation.


Assuntos
Resistência à Insulina , Masculino , Camundongos , Animais , Resistência à Insulina/genética , Tecido Adiposo/metabolismo , Adipócitos/metabolismo , Obesidade/metabolismo , Inflamação/metabolismo , Camundongos Endogâmicos C57BL
15.
Int J Clin Pharm ; 46(1): 90-100, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37817027

RESUMO

BACKGROUND: Various genetic and nongenetic variables influence the high on-treatment platelet reactivity (HTPR) in patients taking clopidogrel. AIM: This study aimed to develop a novel machine learning (ML) model to predict HTPR in Chinese patients after percutaneous coronary intervention (PCI). METHOD: This cohort study collected information on 507 patients taking clopidogrel. Data were randomly divided into a training set (90%) and a testing set (10%). Nine candidate Machine learning (ML) models and multiple logistic regression (LR) analysis were developed on the training set. Their performance was assessed according to the area under the receiver operating characteristic curve, precision, recall, F1 score, and accuracy on the test set. Model interpretations were generated using importance scores by transforming model variables into scaled features and representing in radar plots. Finally, we established a prediction platform for the prediction of HTPR. RESULTS: A total of 461 patients (HTPR rate: 19.52%) were enrolled in building the prediction model for HTPR. The XGBoost model had an optimized performance, with an AUC of 0.82, a precision of 0.80, a recall of 0.44, an F1 score of 0.57, and an accuracy of 0.87, which was superior to those of LR. Furthermore, the XGBoost method identified 7 main predictive variables. To facilitate the application of the model, we established an XGBoost prediction platform consisting of 7 variables and all variables for the HTPR prediction. CONCLUSION: A ML-based approach, such as XGBoost, showed optimum performance and might help predict HTPR on clopidogrel after PCI and guide clinical decision-making. Further validated studies will strengthen this finding.


Assuntos
Clopidogrel , População do Leste Asiático , Intervenção Coronária Percutânea , Humanos , Clopidogrel/farmacologia , Estudos de Coortes , Inibidores da Agregação Plaquetária/farmacologia , Aprendizado de Máquina
16.
Environ Geochem Health ; 46(1): 19, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38147168

RESUMO

Antimony (Sb) and arsenic (As) contamination in agricultural soil poses human health risks through agricultural products. Soil washing with degradable low molecular weight organic acids (LMWOAs) is an eco-friendly strategy to remediate agricultural soils. In this study, three eco-friendly LMWOAs, oxalic acid (OA), tartaric acid (TA), and citric acid (CA), were used to treat Sb and As co-contaminated agricultural soil from Xikuangshan mine area. The OA, TA, and CA washed out 18.4, 16.8, and 26.6% of Sb and 15.3, 19.9, and 23.8% of As from the agricultural soil, with CA being the most efficient reagent for the soil washing. These organic acids also led to pH decline and macronutrients losses. Fraction analysis using a sequential extraction procedure showed that the three organic acids targeted and decreased the specifically sorbed (F2) (by 19.3-37.6% and 2.41-23.5%), amorphous iron oxide associated (F3) (by 49.1-61.2% and 51.2-70.2%), and crystallized iron oxide associated (F4) (by 12.3-26.0% and 26.1-29.1%) Sb and As. The leachability of Sb and As, as well as their concentrations and bioconcentration factor (BCF) in vegetables reduced due to the soil washing. It demonstrated that the bioavailability of both the elements was decreased by the organic acids washing. The concentrations of Sb and As in typical vegetable species cultivated in CA washed soil were less than the threshold value for consumption safety, while those in OA and TA washed soils were still higher than the value, suggesting that only CA is a potential washing reagent in soil washing for Sb- and As-contaminated agricultural soil.


Assuntos
Arsênio , Solo , Humanos , Antimônio , Disponibilidade Biológica , Compostos Orgânicos , Ácido Oxálico , Ácido Cítrico
17.
J Physiol Sci ; 73(1): 32, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37990150

RESUMO

This study was designed to probe the effect of chaperone-assisted selective autophagy (CASA) on the maintenance of proteostasis during exhaustive exercise and uncover the alteration of CASA in muscle fibers with pre-high-intensity interval training (HIIT) intervention-induced muscle adaptation in response to exhaustive exercise. Rats were randomly divided into a control group; an exhaustive exercise group; and an HIIT + exhaustive exercise group. Results show myofibril damage and BiP levels were increased after exhaustive exercise, and the levels of the HSP70, BAG3, ubiquitin, autophagy-related proteins, and their interactions were increased. HIIT intervention before exhaustive exercise could decrease myofibril injury and BiP levels, accompanied by down-regulation of HSP70/BAG3 complex and selective autophagy. In conclusion, exhaustive exercise promotes CASA to clear protein aggregation for keeping proteostasis in muscle fibers; pre-HIIT intervention improves myofibril injury and unfold protein response caused by exhaustive exercise, which might contribute to inhibit the augmentation of CASA.


Assuntos
Treinamento Intervalado de Alta Intensidade , Ratos , Animais , Autofagia/fisiologia , Músculo Esquelético/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Chaperonas Moleculares/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo
18.
Acc Chem Res ; 56(21): 2980-2991, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37851547

RESUMO

Since the discovery of the first chemically modified RNA nucleotide in 1951, more than 170 types of chemical modifications have been characterized in RNA so far. Since the discovery of the reversible and dynamic nature of N6-methyladenosine (m6A) in mRNA modification, researchers have identified about ten modifications in eukaryotic mRNA; together with modifications on the noncoding RNAs, the term "epitranscriptome" has been coined to describe the ensemble of various chemical RNA modifications. The past decade has witnessed the discovery of many novel molecular functions of mRNA modifications, demonstrating their crucial roles in gene expression regulation. As the most abundant modifications in mRNA, the study of m6A and Ψ has been facilitated by innovative high-throughput sequencing technologies, which can be based on antibodies, enzymes, or novel chemistry. Among them, chemical-assisted methods utilize selective chemistry that can discriminate modified versus unmodified nucleotides, enabling the transcriptome-wide mapping of m6A and Ψ modifications and functional studies.Our group has developed several sequencing technologies to investigate these epitranscriptomic marks including m6A, Ψ, m1A, and m6Am. Among them, we have recently developed two methods for absolute quantification of m6A and Ψ in the transcriptome based on chemical reactivity to distinguish and measure the two modifications. In GLORI, we used glyoxal and nitrite to mediate efficient deamination of regular adenosine, while m6A remained unaffected, thereby enabling efficient and unbiased detection of single-base resolution and absolute quantification of m6A modification. In CeU-seq and PRAISE, we used different chemistry to achieve selective labeling and detection of transcriptome-wide Ψ. CeU-seq is based on an azido-derivatized carbodiimide compound, while PRAISE utilizes the unique activity of bisulfite to Ψ. PRAISE results in the formation of ring-opening Ψ-bisulfite adduct and quantitatively detects Ψ as 1-2 nt deletion signatures during sequencing. The resulting base-resolution and stoichiometric information expanded our understanding to the profiles of RNA modifications in the transcriptome. In particular, the quantitative information on RNA methylome is critical for characterizing the dynamic and reversible nature of RNA modifications, for instance, under environmental stress or during development. Additionally, base-resolution and stoichiometric information can greatly facilitate the analysis and characterization of functional modification sites that are important for gene expression regulation, especially when one modification type may have multiple or even opposing functions within a specific transcript. Together, the quantitative profiling methods provide the modification stoichiometry information, which is critical to study the regulatory roles of RNA modifications.In this Account, we will focus on the quantitative sequencing technologies of m6A and Ψ developed in our group, review recent advances in chemical-assisted reactions for m6A and Ψ detection, and discuss the challenges and future opportunities of transcriptome-wide mapping technologies for RNA modifications.


Assuntos
RNA , Transcriptoma , RNA/química , Sulfitos , RNA Mensageiro , Processamento Pós-Transcricional do RNA
19.
Neurotoxicology ; 99: 24-33, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37717738

RESUMO

Methamphetamine (METH) has been established to selectively target and impair dopaminergic neurons through multiple pathways. Ferroptosis is a unique form of non-apoptotic cell death driven by cellular iron accumulation-induced lipid peroxidation. Nonetheless, it remains unclear whether METH can induce ferroptosis. In the present study, we sought to assess alterations in iron levels after chronic METH exposure and reveal the modulatory role of iron on METH-induced pathologies. Importantly, we demonstrated that METH increased iron deposition in the nigrostriatal system, including the substantia nigra (SN) and caudate putamen (CPu). Moreover, decreases in GPx4 levels, increases in lipid peroxidation products, and pathological alterations were observed in the nigrostriatal system as a consequence of chronic METH exposure. The iron chelator deferiprone not only alleviated nigrostriatal iron deposition, dopaminergic cell death, and lipid peroxidation, but alsoattenuated the decreases in GPx4 induced by METH. These findings suggest an alleviation of ferroptosis in dopaminergic neurons. In addition, we found that the ferroptosis inhibitor liproxstatin-1 attenuated METH-induced dopaminergic degeneration in the nigrostriatal system. Our findings corroborated that METH might induce dopaminergic neurodegeneration through iron-dependent ferroptosis. Interestingly, reducing iron levels or inhibiting ferroptosis may alleviate METH-induced dopaminergic neurodegeneration.


Assuntos
Metanfetamina , Camundongos , Animais , Metanfetamina/toxicidade , Dopamina/metabolismo , Encéfalo/metabolismo , Ferro/metabolismo , Quelantes de Ferro/farmacologia
20.
Adv Mater ; 35(42): e2301881, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37718507

RESUMO

The Li-plating behavior of Li-ion batteries under fast-charging conditions is elusive due to a lack of reliable indicators of the Li-plating onset. In this work, the relaxation time constant of the charge-transfer process (τCT ) is proposed to be promising for the determination of Li-plating onset. A novel pulse/relaxation test method enables rapid access to the τCT of the graphite anode during battery operation, applicable to both half and full batteries. The diagnosis of Li plating at varying temperatures and charging rates enriches the cognition of Li-plating behaviors. Li plating at low temperatures and high charging rates can be avoided because of the battery voltage limitations. Nevertheless, after the onset, severe Li plating evolves rapidly under harsh charging conditions, while the Li-plating process under benign charging conditions is accompanied by a simultaneous Li-intercalation process. The quantitative estimates indicate that Li plating at high temperatures/high charging rates leads to more irreversible capacity losses. This facile method with rational scientific principles can provide inspiration for exploring the safe boundaries of Li-ion batteries.

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