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1.
Artigo em Inglês | MEDLINE | ID: mdl-38600805

RESUMO

In the era of the Internet of Things and the rapid progress of artificial intelligence, there is a growing demand for advanced dynamic vision systems. Vision systems are no longer confined to static object detection and recognition, as the detection and recognition of moving objects are becoming increasingly important. To meet the requirements for more precise and efficient dynamic vision, the development of adaptive multimodal motion detection devices becomes imperative. Inspired by the varied response rates in biological vision, we introduce the concept of critical flicker fusion frequency (cFFF) and develop an organic optoelectronic synaptic transistor with adjustable cFFF. In situ Kelvin probe force microscopy analysis reveals that light signal recognition in this device originates from charge transfer in the poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene)-co-(1,3-di(5-thiophene-2-yl)-5,7-bis(2-ethylhexyl)-benzo[1,2-c:4,5-c']dithiophene-4,8-dione)] (PBDB-T)/pentacene heterojunction, which can be effectively modulated by gate voltage. Building upon this, we implement different cFFF within a single device to facilitate the detection and recognition of objects moving at different speeds. This approach allows for resource allocation during dynamic detection, resulting in a reduction in power consumption. Our research holds great potential for enhancing the capabilities of dynamic visual systems.

2.
Adv Sci (Weinh) ; 11(9): e2302093, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38095513

RESUMO

Targeting ferroptosis has attracted exponential attention to eradicate cancer cells with high iron-dependent growth. Increasing the level of intracellular labile iron pool via small molecules and iron-containing nanomaterials is an effective approach to induce ferroptosis but often faces insufficient efficacy due to the fast drug metabolism and toxicity issues on normal tissues. Therefore, developing a long-acting and selective approach to regulate ferroptosis is highly demanded in cancer treatment. Herein, a lysosome-targeted magnetic nanotorquer (T7-MNT) is proposed as the mechanical tool to dynamically induce the endogenous Fe2+ pool outbreak for ferroptosis of breast cancer. T7-MNTs target lysosomes via the transferrin receptor-mediated endocytosis in breast cancer cells. Under the programmed rotating magnetic field, T7-MNTs generate torques to trigger endogenous Fe2+ release by disrupting the lysosomal membrane. This magneto-mechanical manipulation can induce oxidative damage and antioxidant defense imbalance to boost frequency- and time-dependent lipid peroxidization. Importantly, in vivo studies show that T7-MNTs can efficiently trigger ferroptosis under the magnetic field and play as a long-acting physical inducer to boost ferrotherapy efficacy in combination with RSL3. It is anticipated that this dynamic targeted strategy can be coupled with current ferroptosis inducers to achieve enhanced efficacy and inspire the design of mechanical-based ferroptosis inducers for cancer treatment.


Assuntos
Neoplasias da Mama , Ferroptose , Humanos , Feminino , Ferro , Lisossomos , Campos Magnéticos , Neoplasias da Mama/terapia
3.
Light Sci Appl ; 12(1): 264, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37932276

RESUMO

The neuromorphic vision sensor (NeuVS), which is based on organic field-effect transistors (OFETs), uses polar functional groups (PFGs) in polymer dielectrics as interfacial units to control charge carriers. However, the mechanism of modulating charge transport on basis of PFGs in devices is unclear. Here, the carboxyl group is introduced into polymer dielectrics in this study, and it can induce the charge transfer process at the semiconductor/dielectric interfaces for effective carrier transport, giving rise to the best device mobility up to 20 cm2 V-1 s-1 at a low operating voltage of -1 V. Furthermore, the polarity modulation effect could further increase the optical figures of merit in NeuVS devices by at least an order of magnitude more than the devices using carboxyl group-free polymer dielectrics. Additionally, devices containing carboxyl groups improved image sensing for light information decoding with 52 grayscale signals and memory capabilities at an incredibly low power consumption of 1.25 fJ/spike. Our findings provide insight into the production of high-performance polymer dielectrics for NeuVS devices.

4.
ACS Nano ; 17(21): 21690-21707, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37862095

RESUMO

Abnormal mechanical loading often leads to the progressive degradation of cartilage and causes osteoarthritis (OA). Although multiple mechanoresponsive strategies based on biomaterials have been designed to restore healthy cartilage microenvironments, methods to remotely control the on-demand mechanical forces for cartilage repair pose significant challenges. Here, a magneto-mechanically controlled mesenchymal stem cell (MSC) platform, based on the integration of intercellular mechanical communication and intracellular mechanosignaling processes, is developed for OA treatment. MSCs loaded with antioxidative melanin@Fe3O4 magnetic nanoparticles (Magcells) rapidly assemble into highly ordered cell clusters with enhanced cell-cell communication under a time-varying magnetic field, which enables long-term retention and differentiation of Magcells in the articular cavity. Subsequently, via mimicking the gait cycle, chondrogenesis can be further enhanced by the dynamic activation of mechanical signaling processes in Magcells. This sophisticated magneto-mechanical actuation strategy provides a paradigm for developing mechano-therapeutics to repair cartilage in OA treatment.


Assuntos
Cartilagem Articular , Células-Tronco Mesenquimais , Osteoartrite , Humanos , Condrogênese , Condrócitos/metabolismo , Osteoartrite/terapia , Diferenciação Celular
5.
DNA Cell Biol ; 33(11): 802-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25098449

RESUMO

The transforming growth factor-beta (TGF-ß) signaling pathway plays critical roles in the development of various diseases. The current study investigated whether TGF-ß was involved in the pathogenesis of osteosarcoma from the genetic polymorphism perspective and serum level perspective. We first examined two TGF-ß1 polymorphisms, rs1800469C/T and rs1800470T/C, in 202 osteosarcoma patients and 216 healthy controls. Data revealed that the prevalence of rs1800470TT genotype and T allele was significantly elevated in patients than in controls (odds ratio [OR]=2.28, 95% confidence interval [CI]: 1.30-3.98, p<0.001, and OR=1.49, 95% CI: 1.14-1.96, p<0.001). Function analyses showed that healthy controls carrying rs1800470TT genotype had a significantly higher serum level of TGF-ß than those carrying the rs1800470CC genotype (191.1±15.7 pg/mL vs. 129.4±10.9 pg/mL, p=0.003). We then compared the serum level of TGF-ß between osteosarcoma patients and healthy controls. Results demonstrated a significantly increased serum level of TGF-ß in patients than in controls. Further analyses identified that patients with metastasis had augmented levels of serum TGF-ß than those without metastasis. These data indicate that TGF-ß may be closely involved in the pathogenesis of osteosarcoma.


Assuntos
Neoplasias Ósseas/genética , Osteossarcoma/genética , Polimorfismo de Nucleotídeo Único , Fator de Crescimento Transformador beta1/genética , Adolescente , Adulto , Idoso , Neoplasias Ósseas/sangue , Estudos de Casos e Controles , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteossarcoma/sangue , Fator de Crescimento Transformador beta1/sangue , Adulto Jovem
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