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1.
Nano Lett ; 24(29): 8988-8995, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38985015

RESUMO

Exciton-polaritons, hybrid quasiparticles from the strong coupling of excitons and cavity photons in semiconductor microcavities, offer a platform for exploring quantum coherence and nonlinear optical properties. The unique polariton parametric scattering (PPS) laser is of interest for its potential in quantum technologies and nonlinear devices. However, direct resonant excitation of polaritons in strong-coupling microcavities is challenging. This study proposes an innovative two-photon absorption (TPA) pump mechanism to address this. We observe TPA-driven PPS lasing in a strongly coupled microcavity at room temperature. High K-value exciton injections promote coherent stimulated emission of polariton scattering through intermode channels. Angle-resolved spectra confirm a TPA process, showing evolution from pump-state to signal-state. Hanbury Brown-Twiss measurement of second-order correlation g2(τ) of signal state indicates a phase transition from a classical thermal state to a quantum coherent state. Theoretical modeling provides insights into the physical mechanisms of PPS. Our work advances nonlinear phenomena exploration in strongly coupled light-matter systems, contributing to quantum polaritonics and nonlinear optics.

2.
Biol Cybern ; 114(3): 317-336, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32107623

RESUMO

In order to explore the neural mechanism underlying salamander terrestrial turning, an improved biomechanical model is proposed by modifying the forelimb structure of the existing biomechanical model. Based on the proposed improved biomechanical model, a new spinal locomotor network model is constructed which contains the interneuron networks and motoneuron pool. Control methods are also developed for the new model which increase its transient response speed, control the initial swing order of the forelimbs, and generate different walking turning gait and turning on the spot (turning without moving forward). The simulation results show that the biomechanical model controlled by the new spinal locomotor network model can generate different walking turning and turning on the spot, and can control posture and the initial swing order of the forelimbs. Moreover, the transient response speed of the proposed model is very rapid. This paper thus provides a useful tool for exploring the operational mechanism of the spinal circuitry of the salamander. In addition, the research results presented here may inspire the construction of artificial spinal control networks for bionic robots.


Assuntos
Locomoção/fisiologia , Modelos Neurológicos , Redes Neurais de Computação , Territorialidade , Urodelos/fisiologia , Animais , Fenômenos Biomecânicos/fisiologia , Membro Anterior/fisiologia , Caminhada/fisiologia
3.
Biol Cybern ; 112(4): 369-385, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29790009

RESUMO

A salamander is an ideal animal for studying the spinal locomotor network mechanism of vertebrates from an evolutionary perspective since it represents the transition from an aquatic to a terrestrial animal. However, little is known about the spinal locomotor network of a salamander. A spinal locomotor network model is a useful tool for exploring the working mechanism of the spinal networks of salamanders. A new spinal locomotor network model for a salamander is built for a three-dimensional (3D) biomechanical model of the salamander using a novel locomotion-controlled neural network model. Based on recent experimental data on the spinal circuitry and observational results of gaits of vertebrates, we assume that different interneuron sets recruited for mediating the frequency of spinal circuits are also related to the generation of different gaits. The spinal locomotor networks of salamanders are divided into low-frequency networks for walking and high-frequency networks for swimming. Additionally, a new topological structure between the body networks and limb networks is built, which only uses the body networks to coordinate the motion of limbs. There are no direct synaptic connections among limb networks. These techniques differ from existing salamander spinal locomotor network models. A simulation is performed and analyzed to validate the properties of the new spinal locomotor networks of salamanders. The simulation results show that the new spinal locomotor networks can generate a forward walking gait, a backward walking gait, a swimming gait, and a turning gait during swimming and walking. These gaits can be switched smoothly by changing external inputs from the brainstem. These properties are consistent with those of a real salamander. However, it is still difficult for the new spinal locomotor networks to generate highly efficient turning during walking, 3D swimming, nonrhythmic movements, and so on. New experimental data are required for further validation.


Assuntos
Locomoção/fisiologia , Modelos Neurológicos , Vias Neurais/fisiologia , Neurônios/fisiologia , Medula Espinal/fisiologia , Animais , Fenômenos Biomecânicos , Modelos Teóricos , Rede Nervosa/fisiologia , Natação , Urodelos/fisiologia
4.
Nanoscale ; 9(39): 14846-14853, 2017 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-28782781

RESUMO

In recent years, it is prevalent to treat various kinds of the tumors through microwave ablation method. However, it is still very difficult to ablate large tumors by the traditional microwave ablation therapy. In this work, an effective microwave embolization agent designed by encapsulating molybdenum sulfide nanosheets in the sodium alginate microcapsules, denoted as MSMCs, was prepared for the effective therapy of large tumor. The toxicity evaluation showed that MSMC had a good biocompatibility in vitro. The in vitro and in vivo experiments demonstrated that the MSMC was an excellent embolic and microwave susceptible agent that could be used for dual-enhanced microwave ablation therapy. As such, the MSMC showed excellent tumor therapeutic effect with 5 times larger ablation zone observed by magnetic resonance (MR) imaging than the microwave alone after 3 days treating. Besides, the tumor is nearly completely ablated and can not be recurrent due to the persistent hyperthermia. Moreover, MSMCs have a good biocompatibility and can be degraded and cleared from the body. It is believed that the MSMC is demonstrated to be a promising multifunctional theranostic agent used for treating the larger tumor via the synergistic therapy of enhanced microwave ablation and transcatheter arterial embolization (TAE).


Assuntos
Ácido Algínico , Quimioembolização Terapêutica , Neoplasias Hepáticas/terapia , Micro-Ondas , Animais , Cápsulas , Células Hep G2 , Humanos , Camundongos , Nanomedicina Teranóstica
5.
Nanoscale ; 9(25): 8834-8847, 2017 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-28632268

RESUMO

Combined thermo-chemotherapy displays outstanding synergically therapeutic efficiency when compared with standalone thermotherapy and chemotherapy. Herein, we developed a smart tri-stimuli-responsive drug delivery system involving X@BB-ZrO2 NPs (X represents loaded IL, DOX, keratin and tetradecanol) based on novel ball-in-ball-structured ZrO2 nanoparticles (BB-ZrO2 NPs). The microwave energy conversion efficiency of BB-ZrO2 NPs was 41.2% higher than that of traditional single-layer NPs due to the cooperative action of self-reflection and spatial confinement effect of the special two-layer hollow nanostructure. The tri-stimuli-responsive controlled release strategy indicate that integrated pH, redox and microwaves in single NPs based on keratin and tetradecanol could effectively enhance the specific controlled release of DOX. The release of DOX was only 8.1% in PBS with pH = 7.2 and GSH = 20 µM. However, the release could reach about 50% at the tumor site (pH = 5.5, GSH = 13 mM) under microwave ablation. The as-made X@BB-ZrO2 NPs exhibited perfect synergic therapy effect of chemotherapy and microwave ablation both in subcutaneous tumors (H22 tumor-bearing mice) and deep tumors (liver transplantation VX2 tumor-bearing rabbit model). There was no recurrence and death in the X@BB-ZrO2 + MW group during the therapy of subcutaneous tumors even on the 42nd day. The growth rates in the deep tumor of the control, MW and X@BB-ZrO2 + MW groups were 290.1%, 14.1% and -42% 6 days after ablation, respectively. Dual-source CT was used to monitor the metabolism behavior of the as-made BB-ZrO2 NPs and traditional CT was utilized to monitor the tumor growth in rabbits. Frozen section examination and ICP results indicated the precise control of drug delivery and enhanced cytotoxicity by the tri-stimuli-responsive controlled release strategy. The ball-in-ball ZrO2 NPs with high microwave energy conversion efficiency were first developed for synergic microwave ablation and tri-stimuli-responsive chemotherapy, which may have potential applications in clinic.


Assuntos
Nanopartículas , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/tratamento farmacológico , Tomografia Computadorizada por Raios X , Zircônio , Animais , Doxorrubicina , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos ICR , Micro-Ondas , Coelhos , Testes de Toxicidade Aguda
6.
Biomaterials ; 133: 144-153, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28437625

RESUMO

It is an ambitious target to improve overall Hepatocellular Carcinoma therapeutic effects. Recently, MW ablation has emerged as a powerful thermal ablation technique, affording favorable survival with excellent local tumor control. To achieve better therapeutic effects of MW ablation, MW sensitizers are prepared for enhanced MW ablation to preferentially heat tumor territory. However, it is still not practicable for treatment of the orthotopic transplantation tumor. Herein, biocompatible and degradable methoxy poly(ethylene glycol)-poly(lactic-co-glycolic acid) (mPEG-PLGA) microcapsules with hierarchical structure have been designed for microwave-induced tumor therapy. Chemical drug doxorubicin hydrochloride (DOX·HCl), microwave (MW) sensitizers and CT imaging contrast MoS2 nanosheets and MR imaging contrast Fe3O4 nanoparticles are co-incorporated into the microcapsules. In vitro/vivo MR/CT dual-modal imaging results prove the potential application for guiding synergetic therapy and predicting post-therapy tumor progression in the orthotopic transplantation tumor model. After blocking the tumor-feeding arteries, these microcapsules not only exclude the cooling effect by cutting off the blood flow but also enhance MW heating conversion at tumor site. The focused MW heating makes microcapsules mollescent or ruptured and releases DOX·HCl from the microcapsules, achieving the controlled release of drugs for chemical therapy. Compared with MW ablation, 29.4% increase of necrosis diameter of normal liver in rabbit is obtained under MW ablation combined with transcatheter arterial blocking, and the average size of necrosis and inhibition rate of VX-2 liver orthotopic transplantation tumor in rabbit has increased by 129.33% and 73.46%. Moreover, it is proved that the superselectively arterial administration of the as-prepared microcapsules has no recognizable toxicity on the animals. Therefore, this research provides a novel strategy for the construction of MW-induced microcapsules for orthotopic transplantation tumor ablation with the properties of MW sensitizing, superselective arterial blocking, control release and enhanced accumulation of DOX·HCl, and MR/CT dual-modal imaging, which exhibits great potential applications in the field of HCC therapy.


Assuntos
Cápsulas/química , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Micro-Ondas/uso terapêutico , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Doxorrubicina/química , Doxorrubicina/uso terapêutico , Lactatos/química , Ácido Láctico/química , Neoplasias Hepáticas/tratamento farmacológico , Poliésteres/química , Polietilenoglicóis/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos
7.
J Cardiovasc Pharmacol ; 67(1): 57-67, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26335222

RESUMO

Recent evidence has indicated that type 2 diabetes mellitus is related to an increased risk of atrial arrhythmias, which might result from atrial structural and electrical remodeling. Inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase (statins), known as lipid-lowering agents, have been shown to exert antiarrhythmic effects both in experimental models and in humans. In this study, we postulate that atrial structural and calcium channel remodeling may occur in streptozotocin-induced type 2 diabetic rats and can be alleviated by rosuvastatin (RSV) therapy. We randomly divided Wistar rats into control, untreated diabetic, RSV-treated control, and RSV-treated diabetic animals. After treatment with RSV for 4 weeks, rats were assessed by metabolic tests, histopathology, and transmission electron microscopy. The expression of Cav1.2, Cav3.1, and Cav3.2 in atrial tissues was detected by real-time reverse transcriptase polymerase chain reaction and Western blot, and inward calcium currents (l(Ca-L) and l(Ca-T)) were recorded in isolated atrial myocytes using patch-clamp techniques. Compared with controls, diabetic rats displayed severe metabolic disorders and a disorganized cellular ultrastructure. In diabetic rats, the expression of Cav1.2 mRNA and protein was significantly decreased, whereas that of Cav3.1 was significantly increased. Long-term RSV treatment partially relieved some pathological changes in diabetic rats. However, Cav3.2 mRNA and protein remained unchanged in control and diabetic groups and was unaffected by RSV. Diabetic atrial myocytes showed significantly reduced L-type but increased T-type, Ca (2+) currents, and this effect was significantly reversed by RSV. In conclusion, long-term RSV therapy can alleviate structural and calcium channel remodeling in the type 2 diabetic rat atrium.


Assuntos
Canais de Cálcio Tipo L/biossíntese , Canais de Cálcio Tipo T/biossíntese , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Átrios do Coração/efeitos dos fármacos , Átrios do Coração/metabolismo , Rosuvastatina Cálcica/uso terapêutico , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/patologia , Átrios do Coração/patologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Ratos , Ratos Wistar , Rosuvastatina Cálcica/farmacologia
8.
J Mater Chem B ; 4(12): 2133-2141, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-32263180

RESUMO

Microwave (MW) hyperthermia has received great attention as an emerging green tumor thermotherapy. In this work, layered MoS2 nanoflowers were prepared through a simple bottom-up hydrothermal process. By coating MoS2 nanoflowers with bovine serum albumin (BSA-MoS2), BSA-MoS2 exhibits low biotoxicity and excellent microwave susceptive properties in vitro. Meanwhile, the heating effect improvement by the layered structure was confirmed via a computer-simulated experiment. Finally, layered BSA-MoS2 nanoflowers are designed as MW hyperthermia susceptible agents for in vivo cancer therapy with 100% tumor elimination via MW irradiation at 1.8 W, 450 MHz.

9.
Biomaterials ; 44: 91-102, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25617129

RESUMO

This work develops a kind of sodium alginate (SA) microcapsules as microwave susceptible agents for in vivo tumor microwave thermal therapy for the first time. Due to the excellent microwave susceptible properties and low bio-toxicity, excellent therapy efficiency can be achieved with the tumor inhibiting ratio of 97.85% after one-time microwave thermal therapy with ultralow power (1.8 W, 450 MHz). Meanwhile, the mechanism of high microwave heating efficiency was confirmed via computer-simulated model in theory, demonstrating that the spatial confinement efficiency of microcapsule walls endows the inside ions with high microwave susceptible properties. This strategy offers tremendous potential applications in clinical tumor treatment with the benefits of safety, reliability, effectiveness and minimally invasiveness.


Assuntos
Hipertermia Induzida/métodos , Micro-Ondas , Neoplasias/terapia , Animais , Cápsulas , Morte Celular , Sobrevivência Celular , Simulação por Computador , Feminino , Calefação , Hemólise , Células Hep G2 , Humanos , Injeções Subcutâneas , Camundongos Endogâmicos ICR , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Coelhos , Termogravimetria , Testes de Toxicidade
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