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1.
Nat Mater ; 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702413

RESUMEN

Electrochemomechanical degradation is one of the most common causes of capacity deterioration in high-energy-density cathodes, particularly intercalation-based layered oxides. Here we reveal the presence of rotational stacking faults (RSFs) in layered lithium transition-metal oxides, arising from specific stacking sequences at different angles, and demonstrate their critical role in determining structural/electrochemical stability. Our combined experiments and calculations show that RSFs facilitate oxygen dimerization and transition-metal migration in layered oxides, fostering microcrack nucleation/propagation concurrently with cumulative electrochemomechanical degradation on cycling. We further show that thermal defect annihilation as a potential solution can suppress RSFs, reducing microcracks and enhancing cyclability in lithium-rich layered cathodes. The common but previously overlooked occurrence of RSFs suggests a new synthesis guideline of high-energy-density layered oxide cathodes.

2.
Nat Commun ; 15(1): 1288, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38346943

RESUMEN

O2-type lithium-rich layered oxides, known for mitigating irreversible transition metal migration and voltage decay, provide suitable framework for exploring the inherent properties of oxygen redox. Here, we present a series of O2-type lithium-rich layered oxides exhibiting minimal structural disordering and stable voltage retention even with high anionic redox participation based on the nominal composition. Notably, we observe a distinct asymmetric lattice breathing phenomenon within the layered framework driven by excessive oxygen redox, which includes substantial particle-level mechanical stress and the microcracks formation during cycling. This chemo-mechanical degradation can be effectively mitigated by balancing the anionic and cationic redox capabilities, securing both high discharge voltage (~ 3.43 V vs. Li/Li+) and capacity (~ 200 mAh g-1) over extended cycles. The observed correlation between the oxygen redox capability and the structural evolution of the layered framework suggests the distinct intrinsic capacity fading mechanism that differs from the previously proposed voltage fading mode.

3.
Science ; 382(6670): 573-579, 2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37917684

RESUMEN

Lithium-metal-halides have emerged as a class of solid electrolytes that can deliver superionic conductivity comparable to that of state-of-the-art sulfide electrolytes, as well as electrochemical stability that is suitable for high-voltage (>4 volt) operations. We show that the superionic conduction in a trigonal halide, such as Li3MCl6 [where metal (M) is Y or Er], is governed by the in-plane lithium percolation paths and stacking interlayer distance. These two factors are inversely correlated with each other by the partial occupancy of M, serving as both a diffusion inhibitor and pillar for maintaining interlayer distance. These findings suggest that a critical range or ordering of M exists in trigonal halides, and we showcase the achievement of high ionic conductivity by adjusting the simple M ratio (per Cl or Li). We provide general design criteria for superionic trigonal halide electrolytes.

4.
BMC Cancer ; 23(1): 831, 2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37670250

RESUMEN

BACKGROUND: Heterogeneous tumor cells are thought to be a significant factor in the failure of endocrine therapy in estrogen receptor-positive (ER+) cancers. Culturing patient-derived breast cancer cells (PDBCCs) provides an invaluable tool in pre-clinical and translational research for the heterogeneity of cancer cells. This study aimed to investigate the effects of different media components and culture methods on the BCSC-associated immunophenotypes and gene expression in ER + PDBCCs. METHODS: Ten patients with ER + breast cancer were employed in this study, six of whom had neoadjuvant chemotherapy and four of whom did not. PDBCCs were isolated by enzymatic methods using collagen I and hyaluronidase. PDBCCs were grown as monolayers in mediums with different compositions and as multicellular spheroid in a suspended condition. Collagen I-coated plate and ultralow attachment plate coated with polymer-X were used for monolayer and spheroid culture. Flow cytometry, immunofluorescent staining, RT-PCR, and RNA-sequencing were employed to examine the immunophenotype and genetic profile of PDBCCs. RESULTS: More than 95% of PDBCCs sustain EpCAM high/+/fibroblast marker- phenotypes in monolayer conditions by subculturing 3-4 times. A83-01 removal induced senescent cells with high ß-galactosidase activity. PDBCCs grown as monolayers were characterized by the majority of cells having an EpCAM+/CD49f + phenotype. Compared to full media in monolayer culture, EGF removal increased EpCAM+/CD49f - phenotype (13.8-fold, p = 0.028), whereas R-spondin removal reduced it (0.8-fold, p = 0.02). A83-01 removal increased EpCAM+/CD24 + phenotype (1.82-fold, p = 0.023) and decreased EpCAM low/-/CD44+/CD24- phenotype (0.45-fold, p = 0.026). Compared to monolayer, spheroid resulted in a significant increase in the population with EpCAM-/CD49+ (14.6-fold, p = 0.006) and EpCAM low/-/CD44+/CD24- phenotypes (4.16-fold, p = 0.022) and ALDH high activity (9.66-fold, p = 0.037). ALDH1A and EMT-related genes were upregulated. In RNA-sequencing analysis between spheroids and monolayers, a total of 561 differentially expressed genes (2-fold change, p < 0.05) were enriched in 27 KEGG pathways including signaling pathways regulating pluripotency of stem cells. In a recurrence-free survival analysis based on the Kaplan-Meier Plotter database of the up-and down-regulated genes identified in spheroids, 15 up-, and 14 down-regulated genes were associated with poor prognosis of breast cancer patients. CONCLUSION: The media composition and spheroid culture method change in the BCSCs and EMT markers of PDBCCs, implying the importance of defining the media composition and culture method for studying PDBCCs in vitro.


Asunto(s)
Colágeno Tipo I , Neoplasias , Molécula de Adhesión Celular Epitelial , Integrina alfa6 , ARN
5.
Nat Commun ; 14(1): 4149, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37438468

RESUMEN

Lithium-rich layered oxides, despite their potential as high-energy-density cathode materials, are impeded by electrochemical performance deterioration upon anionic redox. Although this deterioration is believed to primarily result from structural disordering, our understanding of how it is triggered and/or occurs remains incomplete. Herein, we propose a theoretical picture that clarifies the irreversible transformation and redox asymmetry of lithium-rich layered oxides by introducing a series of global and local dynamic structural evolution processes involving slab gliding and transition-metal migration. We show that slab gliding plays a key role in trigger/initiating the structural disordering and consequent degradation of the anionic redox reaction. We further reveal that the 'concerted disordering mechanism' of slab gliding and transition-metal migration produces spontaneously irreversible/asymmetric lithiation and de-lithiation pathways, causing irreversible structural deterioration and the asymmetry of the anionic redox reaction. Our findings suggest slab gliding as a crucial, yet underexplored, method for achieving a reversible anionic redox reaction.

6.
Artículo en Inglés | MEDLINE | ID: mdl-37013725

RESUMEN

Recently, the impressive efficacy of JAK-inhibitors (JAK-I) in alopecia areata (AA) has been described in several studies; however, to date, there is limited information on the safety of JAK-I in AA patients. For this reason, on 18 August 2022, a systematic review was performed to collect the premarketing and postmarketing data on the safety of JAK-I in patients treated for AA, evaluating for each molecule the reported adverse events (AEs) in indexed literature and their frequency. The keywords 'alopecia areata' AND 'Jak-inhibitors OR Janus-kinase Inhibitors' were searched on PubMed, Embase and Cochrane databases. Of 407 studies retrieved, 28 papers met the requirements and were used in our review, including five RCTs and 23 case series; overall, 1719 patients were included, and the safety of 6 JAK-I was assessed (baricitinib, brepocitinib, deuruxolitinib, ritlecitinib, ruxolitinib and tofacitinib). Systemic JAK-I were well-tolerated, most of the AEs were mild, and the withdrawal rate for AEs was very low and inferior to placebo in controlled studies (1.6% vs. 2.2%). Laboratory abnormalities represented 40.1% of AEs associated with oral JAK-I, which mostly included the rise in cholesterol, transaminase, triglycerides, creatine phosphokinase (CPK) and sporadic cases of neutro/lymphocytopenia. The remaining AEs involved the respiratory tract (20.8%), the skin (17.2%), the urogenital (3.8%), or the gastroenterological (3.4%) tract. Increased rates of infections involved not only the upper (19.0%) and lower (0.3%) respiratory tract, but also the urogenital system (3.6%) and the skin (4.6%). Isolated cases of grade 3 to 4 AEs have been reported, including myocardial infarction, hypertensive urgencies, cellulitis, rhabdomyolysis, neutropenia and high elevation of creatinine kinase. No fatal outcomes were reported. AEs reported with topical formulation included scalp irritation and folliculitis. The main limit of this review is the lack of data related to postmarketing surveillance, which should be maintained on a long-term basis.

7.
Biomedicines ; 10(11)2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36359204

RESUMEN

Cancer stem-like cells (CSCs) are considered promising targets for anti-cancer therapy owing to their role in tumor progression. Extensive research is, therefore, being carried out on CSCs to identify potential targets for anti-cancer therapy. However, this requires the availability of patient-derived CSCs ex vivo, which remains restricted due to the low availability and diversity of CSCs. To address this limitation, a functional polymer thin-film (PTF) platform was invented to induce the transformation of cancer cells into tumorigenic spheroids. In this study, we demonstrated the functionality of a new PTF, polymer X, using a streamlined production process. Polymer X induced the formation of tumor spheroids with properties of CSCs, as revealed through the upregulated expression of CSC-related genes. Signal transducer and activator of transcription 3 (STAT3) phosphorylation in the cancer cells cultured on polymer X was upregulated by the fibronectin-integrin α5-Janus kinase 2 (JAK2) axis and maintained by the cytosolic LMO2/LBD1 complex. In addition, STAT3 signaling was critical in spheroid formation on polymer X. Our PTF platform allows the efficient generation of tumor spheroids from cancer cells, thereby overcoming the existing limitations of cancer research.

8.
Nat Mater ; 21(6): 664-672, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35301474

RESUMEN

Lattice oxygen redox offers an unexplored way to access superior electrochemical properties of transition metal oxides (TMOs) for rechargeable batteries. However, the reaction is often accompanied by unfavourable structural transformations and persistent electrochemical degradation, thereby precluding the practical application of this strategy. Here we explore the close interplay between the local structural change and oxygen electrochemistry during short- and long-term battery operation for layered TMOs. The substantially distinct evolution of the oxygen-redox activity and reversibility are demonstrated to stem from the different cation-migration mechanisms during the dynamic de/intercalation process. We show that the π stabilization on the oxygen oxidation initially aids in the reversibility of the oxygen redox and is predominant in the absence of cation migrations; however, the π-interacting oxygen is gradually replaced by σ-interacting oxygen that triggers the formation of O-O dimers and structural destabilization as cycling progresses. More importantly, it is revealed that the distinct cation-migration paths available in the layered TMOs govern the conversion kinetics from π to σ interactions. These findings constitute a step forward in unravelling the correlation between the local structural evolution and the reversibility of oxygen electrochemistry and provide guidance for further development of oxygen-redox layered electrode materials.


Asunto(s)
Óxidos , Oxígeno , Suministros de Energía Eléctrica , Electroquímica , Oxidación-Reducción , Oxígeno/química
9.
Adv Mater ; 33(10): e2004902, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33533125

RESUMEN

The production of rechargeable batteries is rapidly expanding, and there are going to be new challenges in the near future about how the potential environmental impact caused by the disposal of the large volume of the used batteries can be minimized. Herein, a novel strategy is proposed to address these concerns by applying biodegradable device technology. An eco-friendly and biodegradable sodium-ion secondary battery (SIB) is developed through extensive material screening followed by the synthesis of biodegradable electrodes and their seamless assembly with an unconventional biodegradable separator, electrolyte, and package. Each battery component decomposes in nature into non-toxic compounds or elements via hydrolysis and/or fungal degradation, with all of the biodegradation products naturally abundant and eco-friendly. Detailed biodegradation mechanisms and toxicity influence of each component on living organisms are determined. In addition, this new SIB delivers performance comparable to that of conventional non-degradable SIBs. The strategy and findings suggest a novel eco-friendly biodegradable paradigm for large-scale rechargeable battery systems.

10.
Nanotechnology ; 30(31): 315502, 2019 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-30893673

RESUMEN

In the last decade, extensive studies have been conducted to realize the functions of human skin based on stretchable electronics. An artificial skin, recognizing complex mechanical stimulation including pressure, strain and shear, and composed of transparent material, is an essential goal but has hardly been achieved. We fabricated a transparent integrated sensor system that can sense the strain direction and normal pressure of applied mechanical stimulation. Each sensor is composed of micropatterned Ag nanowire, forming a composite stretchable conductor with a block copolymer elastomer. The micropatterning and transfer process using thermoplastic elastomer facilitates the transparent conductor to show high transmittance with low sheet resistance at the same time. The designed transparent strain sensor responds linearly to strain, but does not respond to the orthogonal direction, which enables it to have strain-directionality. The applied mechanical signal, comprising normal force and directional strain, can be interpreted through the electrical signal observed from integrated sensors.

11.
Cancer Res ; 78(24): 6890-6902, 2018 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-30352813

RESUMEN

: Although cancer stem cells (CSC) are thought to be responsible for tumor recurrence and resistance to chemotherapy, CSC-related research and drug development have been hampered by the limited supply of diverse, patient-derived CSC. Here, we present a functional polymer thin film (PTF) platform that promotes conversion of cancer cells to highly tumorigenic three-dimensional (3D) spheroids without the use of biochemical or genetic manipulations. Culturing various human cancer cells on the specific PTF, poly(2,4,6,8-tetravinyl-2,4,6,8-tetramethyl cyclotetrasiloxane) (pV4D4), gave rise to numerous multicellular tumor spheroids within 24 hours with high efficiency and reproducibility. Cancer cells in the resulting spheroids showed a significant increase in the expression of CSC-associated genes and acquired increased drug resistance compared with two-dimensional monolayer-cultured controls. These spheroids also exhibited enhanced xenograft tumor-forming ability and metastatic capacity in nude mice. By enabling the generation of tumorigenic spheroids from diverse cancer cells, the surface platform described here harbors the potential to contribute to CSC-related basic research and drug development. SIGNIFICANCE: A new cell culture technology enables highly tumorigenic 3D spheroids to be easily generated from various cancer cell sources in the common laboratory.


Asunto(s)
Células Madre Neoplásicas/citología , Polímeros/química , Esferoides Celulares/citología , Animales , Carcinogénesis/metabolismo , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Femenino , Genoma , Células HeLa , Células Hep G2 , Humanos , Células MCF-7 , Ensayo de Materiales , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/patología , Reproducibilidad de los Resultados
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