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1.
J Am Chem Soc ; 146(5): 3553-3563, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38285529

RESUMEN

Flexible membranes with ultrathin thickness and excellent mechanical properties have shown great potential for broad uses in solid polymer electrolytes (SPEs), on-skin electronics, etc. However, an ultrathin membrane (<5 µm) is rarely reported in the above applications due to the inherent trade-off between thickness and antifailure ability. We discover a protic solvent penetration strategy to prepare ultrathin, ultrastrong layered films through a continuous interweaving of aramid nanofibers (ANFs) with the assistance of simultaneous protonation and penetration of a protic solvent. The thickness of a pure ANF film can be controlled below 5 µm, with a tensile strength of 556.6 MPa, allowing us to produce the thinnest SPE (3.4 µm). The resultant SPEs enable Li-S batteries to cycle over a thousand times at a high rate of 1C due to the small ionic impedance conferred by the ultrathin characteristic and regulated ionic transportation. Besides, a high loading of the sulfur cathode (4 mg cm-2) with good sulfur utilization was achieved at a mild temperature (35 °C), which is difficult to realize in previously reported solid-state Li-S batteries. Through a simple laminating process at the wet state, the thicker film (tens of micrometers) obtained exhibits mechanical properties comparable to those of thin films and possesses the capability to withstand high-velocity projectile impacts, indicating that our technique features a high degree of thickness controllability. We believe that it can serve as a valuable tool to assemble nanomaterials into ultrathin, ultrastrong membranes for various applications.

2.
Medicine (Baltimore) ; 103(4): e37000, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38277530

RESUMEN

INTRODUCTION: Klippel Trenaunay syndrome (KTS) is a rare congenital disorder characterized by wine staining, varicose veins, bone hypertrophy, and soft tissue hyperplasia. KTS usually occurs at birth, early infancy or childhood. The rarity of disease makes it difficult to calculate its incidence rate. However, few studies report the incidence rate of 2 to 5 cases per 100 thousand. Furthermore, evidence demonstrates that KTS is more prevalent among males compared to females. CASE PRESENTATION: An elderly male aged 67, was admitted to the hospital for chronic pain in his left knee. An outpatient physical examination reveals a significantly thicker left lower limb accompanied by multiple varicose veins. The right lower limb was 2 cm short on the opposite side, and the right foot was stunted with high arch deformity. The entire body was covered in a red grape globus, which faded after pressing. He was diagnosed with KTS. We performed TKA for him after blood coagulation examination. The patient recovered well after the operation. He was followed up for 1 year, The patient is in good condition and satisfied with the operation. CONCLUSION: For patients with KTS, total knee arthroplasty is an effective surgical procedure to treat arthritis. However, some risks must be considered, and appropriate surgical preparation must be undertaken.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Síndrome de Klippel-Trenaunay-Weber , Osteoartritis de la Rodilla , Várices , Anciano , Humanos , Masculino , Síndrome de Klippel-Trenaunay-Weber/complicaciones , Extremidad Inferior/cirugía , Osteoartritis de la Rodilla/cirugía , Osteoartritis de la Rodilla/complicaciones , Várices/cirugía
3.
ACS Omega ; 9(19): 21569-21579, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38764695

RESUMEN

Two cylindrical section hydrocyclones can suppress particle misplacement by regulating the circulation flow, but few researchers have investigated the effect of the cylindrical height ratio. In this paper, numerical simulations and physical tests were conducted to investigate the effect of height ratio on the particle motion behavior and separation performance of the two cylindrical section hydrocyclone. According to the numerical simulation results, with increasing height ratio, the separation cut size decreased, the separation accuracy and recovery rate of medium and coarse particles in the underflow increased, the coarse particle misplacement in overflow decreased significantly, and the proportion of medium particle circulation flow gradually increased. According to the test results, the number of misplaced fine particles in underflow could be effectively reduced when H1/H0 = 0.30. With increasing height ratio, the number of misplaced coarse particles in the overflow decreased and the classification efficiency of fine particles increased. The maximum separation efficiencies of medium and coarse particles could be obtained at H1/H0 values of 0.47 and 0.17, respectively. Therefore, increasing the height ratio could inhibit coarse particle misplacement in overflow and improve the separation performance of two cylindrical section hydrocyclones.

4.
Global Spine J ; : 21925682241226956, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38228505

RESUMEN

STUDY DESIGN: A retrospective study. OBJECTIVES: This study aimed to check how accurately cages were inserted and how they affected the radiological results in oblique lumbar interbody fusion (OLIF) at L2-L5. METHODS: A total of 137 patients diagnosed with lumbar degenerative disease, 184 intervertebral discs were included. We used a new cage deviation classification system on magnetic resonance imaging (MRI) to determine cage insertion accuracy. Cage deviation angles (CDA) were classified into four groups based on the angle formed by the long axis of the cage and the horizontal axis of the vertebral body. Other radiological parameters on plain radiographs and MRI were compared based on this classification. RESULTS: Among 183 cages, 19 were in zone Ⅰ-Ⅱ (10.32%), 163 were in zone II-III (88.59%), and two were in zone III-IV (1.09%). The median cage deviation was 4.97°. No significant differences (H = 2.479, P = .290 > .05) of CDA were found among different segments. Posterior cage deviation accounted 94.57%. The minimal, mild, moderate, and severe cage deviation was 89 (48.4%), 51 (27.7%), 30 (16.3%), and 14 (7.6%) respectively. No differences in radiological parameter changes were noted among different cage obliquity categories. CONCLUSIONS: Approximately 98.91% of cages were placed in zones I-II and II-III. Most cages deviated posteriorly with CDA ranging minimal to moderate. Minimal to moderate cage deviation did not impact radiological outcomes significantly in OLIF at L2-L5. However, avoiding severe cage deviation is crucial to prevent contralateral traversing nerve root injuries.

5.
Adv Mater ; : e2405790, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39015059

RESUMEN

Lithium-sulfur (Li-S) batteries suffer from severe polysulfide shuttle, retarded sulfur conversion kinetics and notorious lithium dendrites, which has curtailed the discharge capacity, cycling lifespan and safety. Engineered catalysts act as a feasible strategy to synchronously manipulate the evolution behaviors of sulfur and lithium species. Herein, a chlorine bridge-enabled binuclear copper complex (Cu-2-T) is in situ synthesized in electrolyte as homogeneous catalyst for rationalizing the Li-S redox reactions. The well-designed Cu-2-T provides completely active sites and sufficient contact for homogeneously guiding the Li2S nucleation/decomposition reactions, and stabilizing the lithium working interface according to the synchrotron radiation X-ray 3D nano-computed tomography, small angle neutron scattering and COMSOL results. Moreover, Cu-2-T with the content of 0.25 wt% approaching saturated concentration in electrolyte further boosts the homogeneous optimization function in really operated Li-S batteries. Accordingly, the capacity retention of the Li-S battery is elevated from 51.4% to 86.3% at 0.2 C, and reaches 77.0% at 1.0 C over 400 cycles. Furthermore, the sulfur cathode with the assistance of Cu-2-T realizes the stable cycling under the practical scenarios of soft-packaged pouch cell and high sulfur loading (6.5 mg cm-2 with the electrolyte usage of 4.5 µL mgS -1).

6.
ACS Nano ; 18(26): 16674-16683, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38907991

RESUMEN

Targeted nanoparticles have been extensively explored for their ability to deliver their payload to a selective cell population while reducing off-target side effects. The design of actively targeted nanoparticles requires the grafting of a ligand that specifically binds to a highly expressed receptor on the surface of the targeted cell population. Optimizing the interactions between the targeting ligand and the receptor can maximize the cellular uptake of the nanoparticles and subsequently improve their activity. Here, we evaluated how the density and presentation of the targeting ligands dictate the cellular uptake of nanoparticles. To do so, we used a DNA-scaffolded PLGA nanoparticle system to achieve efficient and tunable ligand conjugation. A prostate-specific membrane antigen (PSMA) expressing a prostate cancer cell line was used as a model. The density and presentation of PSMA targeting ligand ACUPA were precisely tuned on the DNA-scaffolded nanoparticle surface, and their impact on cellular uptake was evaluated. It was found that matching the ligand density with the cell receptor density achieved the maximum cellular uptake and specificity. Furthermore, DNA hybridization-mediated targeting chain rigidity of the DNA-scaffolded nanoparticle offered ∼3 times higher cellular uptake compared to the ACUPA-terminated PLGA nanoparticle. Our findings also indicated a ∼ 3.7-fold reduction in the cellular uptake for the DNA hybridization of the non-targeting chain. We showed that nanoparticle uptake is energy-dependent and follows a clathrin-mediated pathway. Finally, we validated the preferential tumor targeting of the nanoparticles in a bilateral tumor xenograft model. Our results provide a rational guideline for designing actively targeted nanoparticles and highlight the application of DNA-scaffolded nanoparticles as an efficient active targeting platform.


Asunto(s)
ADN , Glutamato Carboxipeptidasa II , Nanopartículas , Neoplasias de la Próstata , Nanopartículas/química , Humanos , ADN/química , ADN/metabolismo , Ligandos , Masculino , Glutamato Carboxipeptidasa II/metabolismo , Glutamato Carboxipeptidasa II/química , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Animales , Línea Celular Tumoral , Ratones , Antígenos de Superficie/metabolismo , Antígenos de Superficie/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química
7.
Nat Commun ; 15(1): 3231, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622167

RESUMEN

Engineering atom-scale sites are crucial to the mitigation of polysulfide shuttle, promotion of sulfur redox, and regulation of lithium deposition in lithium-sulfur batteries. Herein, a homonuclear copper dual-atom catalyst with a proximal distance of 3.5 Å is developed for lithium-sulfur batteries, wherein two adjacent copper atoms are linked by a pair of symmetrical chlorine bridge bonds. Benefiting from the proximal copper atoms and their unique coordination, the copper dual-atom catalyst with the increased active interface concentration synchronously guide the evolutions of sulfur and lithium species. Such a delicate design breaks through the activity limitation of mononuclear metal center and represents a catalyst concept for lithium-sulfur battery realm. Therefore, a remarkable areal capacity of 7.8 mA h cm-2 is achieved under the scenario of sulfur content of 60 wt.%, mass loading of 7.7 mg cm-2 and electrolyte dosage of 4.8 µL mg-1.

8.
Adv Mater ; 36(29): e2400115, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38752837

RESUMEN

All-solid-state lithium metal batteries (ASSLMBs) are considered as the most promising candidates for the next-generation high-safety batteries. To achieve high energy density in ASSLMBs, it is essential that the solid-state electrolytes (SSEs) are lightweight, thin, and possess superior electrochemical stability. In this study, a feasible and scalable fabrication approach to construct 3D supporting skeleton using an electro-blown spinning technique is proposed. This skeleton not only enhances the mechanical strength but also hinders the migration of Li-salt anions, improving the lithium-ion transference number of the SSE. This provides a homogeneous distribution of Li-ion flux and local current density, promoting uniform Li deposition. As a result, based on the mechanically robust and thin SSEs, the Li symmetric cells show outstanding Li plating/stripping reversibility. Besides, a stable interface contact between SSE and Li anode has been established with the formation of an F-enriched solid electrolyte interface layer. The solid-state Li|sulfurized polyacrylonitrile (Li|SPAN) cell achieves a capacity retention ratio of 94.0% after 350 cycles at 0.5 C. Also, the high-voltage Li|LCO cell shows a capacity retention of 92.4% at 0.5 C after 500 cycles. This fabrication approach for SSEs is applicable for commercially large-scale production and application in high-energy-density and high-safety ASSLMBs.

9.
Nat Commun ; 15(1): 3914, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724546

RESUMEN

Solid polymer electrolytes exhibit enhanced Li+ conductivity when plasticized with highly dielectric solvents such as N,N-dimethylformamide (DMF). However, the application of DMF-containing electrolytes in solid-state batteries is hindered by poor cycle life caused by continuous DMF degradation at the anode surface and the resulting unstable solid-electrolyte interphase. Here we report a composite polymer electrolyte with a rationally designed Hofmann-DMF coordination complex to address this issue. DMF is engineered on Hofmann frameworks as tethered ligands to construct a locally DMF-rich interface which promotes Li+ conduction through a ligand-assisted transport mechanism. A high ionic conductivity of 6.5 × 10-4 S cm-1 is achieved at room temperature. We demonstrate that the composite electrolyte effectively reduces the free shuttling and subsequent decomposition of DMF. The locally solvent-tethered electrolyte cycles stably for over 6000 h at 0.1 mA cm-2 in Li | |Li symmetric cell. When paired with sulfurized polyacrylonitrile cathodes, the full cell exhibits a prolonged cycle life of 1000 cycles at 1 C. This work will facilitate the development of practical polymer-based electrolytes with high ionic conductivity and long cycle life.

10.
Nat Cell Biol ; 26(6): 878-891, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38783142

RESUMEN

When cells are stressed, DNA from energy-producing mitochondria can leak out and drive inflammatory immune responses if not cleared. Cells employ a quality control system called autophagy to specifically degrade damaged components. We discovered that mitochondrial transcription factor A (TFAM)-a protein that binds mitochondrial DNA (mtDNA)-helps to eliminate leaked mtDNA by interacting with the autophagy protein LC3 through an autolysosomal pathway (we term this nucleoid-phagy). TFAM contains a molecular zip code called the LC3 interacting region (LIR) motif that enables this binding. Although mutating TFAM's LIR motif did not affect its normal mitochondrial functions, more mtDNA accumulated in the cell cytoplasm, activating inflammatory signalling pathways. Thus, TFAM mediates autophagic removal of leaked mtDNA to restrict inflammation. Identifying this mechanism advances understanding of how cells exploit autophagy machinery to selectively target and degrade inflammatory mtDNA. These findings could inform research on diseases involving mitochondrial damage and inflammation.


Asunto(s)
Autofagia , ADN Mitocondrial , Proteínas de Unión al ADN , Inflamación , Mitocondrias , Proteínas Mitocondriales , Factores de Transcripción , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Inflamación/metabolismo , Inflamación/patología , Inflamación/genética , Animales , Humanos , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Mitocondrias/metabolismo , Mitocondrias/genética , Ratones , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Asociadas a Microtúbulos/genética , Unión Proteica , Citoplasma/metabolismo , Lisosomas/metabolismo , Transducción de Señal , Células HEK293 , Ratones Endogámicos C57BL , Proteínas del Grupo de Alta Movilidad
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