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1.
Opt Lett ; 49(16): 4589-4592, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39146110

RESUMO

Free-space strong-field terahertz (THz) electromagnetic pulses have emerged as a potent tool for non-equilibrium quantum state control. However, these applications predominantly rely on electric field components, with limited utilization of magnetic field components. A traditional electro-optical sampling technique may encounter constraints due to the field strength saturation effect when detecting strong-field THz pulses. Here we have identified intense THz-induced Zeeman torque signals in CoFe and successfully detected the THz magnetic field components. Through variations in the type of ferromagnetic materials and the thickness of ferromagnetic films, we further refined the detection of THz magnetic field components. Our research revealed that a 15-nm CoFe thin film is more responsive in measuring magnetic field components.

2.
Comput Biol Med ; 165: 107369, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37625259

RESUMO

Porous scaffold (PorS) implants, particularly those that mimic the structural features of natural cancellous bone (NCanB), are increasingly essential for the treatment of large-area bone defects. However, the mechanical properties of NCanB-based bionic bone scaffold (BioS) and its performance as a bone repair material have not been fully explored. This study investigates the effect of bionic structure parameters on the mechanical properties and bone reconstruction performance of BioS. Using laser powder bed fusion (L-PBF) technology, different BioS with various structural parameters were created and evaluated using Micro-CT, compression testing, Finite Element (FE) Simulation, and computational fluid dynamics (CFD), and compared to commonly used clinical PorS. Assess the capacity of the BioS scaffold to support and enhance bone reconstruction following implantation through the evaluation of its mechanical properties, permeability, and fluid shear stress (FSS). BioS-85-90 and BioS-80-50 showed suitable mechanical properties, performed well in FE simulation of implantation, demonstrated outstanding abilities for osteoinductive ingrowth and bone tissue differentiation, and proved to be reliable materials for the reconstruction of bone defects. Therefore, BioS shows significant potential for clinical application as a bone reconstruction material, providing a solid foundation for the integration of tissue engineering and bionic design.


Assuntos
Biomimética , Osso e Ossos , Teste de Materiais , Osso e Ossos/cirurgia , Engenharia Tecidual , Próteses e Implantes , Porosidade
3.
Adv Mater ; 35(23): e2208947, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36932897

RESUMO

Extremely strong-field terahertz (THz) radiation in free space has compelling applications in nonequilibrium condensed matter state regulation, all-optical THz electron acceleration and manipulation, THz biological effects, etc. However, these practical applications are constrained by the absence of high-intensity, high-efficiency, high-beam-quality, and stable solid-state THz light sources. Here, the generation of single-cycle 13.9-mJ extreme THz pulses from cryogenically cooled lithium niobate crystals and a 1.2% energy conversion efficiency from 800 nm to THz are demonstrated experimentally using the tilted pulse-front technique driven by a home-built 30-fs, 1.2-Joule Ti:sapphire laser amplifier. The focused peak electric field strength is estimated to be 7.5 MV cm-1 . A record of 1.1-mJ THz single-pulse energy at a 450 mJ pump at room temperature is produced and observed that the self-phase modulation of the optical pump can induce THz saturation behavior from the crystals in the substantially nonlinear pump regime. This study lays the foundation for the generation of sub-Joule THz radiation from lithium niobate crystals and will inspire more innovations in extreme THz science and applications.

4.
Carbohydr Polym ; 251: 117081, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142624

RESUMO

It seems quite necessary for obtaining effective substances from natural products against the diabetic nephropathic (DN) with the presently clinical problems of accompanying side-effects and lowing life qualities. This work aimed to characterize the primary structure of Coprinus comatus mycelium polysaccharides (CMP) and investigate the abilities against DN in streptozotocin induced mice models. The results indicated that CMP could improve insulin resistance and energy metabolism, and significantly suppress dysfunction on kidney and relieve the renal oxidative stress and inflammation in DN mice. Besides, the western blot results suggested that CMP reversed renal injury by modulating the PTEN/PI3K/Akt and Wnt-1/ß-catenin pathways. The structure analysis indicated the typical characterizations with the major monosaccharide-compositions of galactose, α-pyranose configuration and proper molecular weights of 495.8 kDa possibly contributed to the anti-diabetic nephropathic effects of CMP. The results suggested that polysaccharides form C. comatus could be used as functional foods/drugs on preventing diabetic nephropathy.


Assuntos
Antioxidantes/metabolismo , Coprinus/química , Diabetes Mellitus Experimental/complicações , Nefropatias Diabéticas/tratamento farmacológico , Micélio/química , Polissacarídeos/farmacologia , Animais , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/metabolismo , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Masculino , Metformina/farmacologia , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Polissacarídeos/química , Via de Sinalização Wnt
5.
Biomed Pharmacother ; 130: 110516, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32674018

RESUMO

Autologous or allogeneic bone grafts are common methods to treat bone defects. Bone tissue engineering combining carrier material with the active factor can induce a generation of new bone at the bone defect site. However, its clinical application is restricted by the limited donors, the high morbidity at the donor site, the low activity in vivo, and dose-independent adverse effect. To overcome the limitations of traditional therapies, it is urgent to find and develop a repair material that can replace natural bones. Hence, we designed and prepared suitable MPEG-PCL microspheres loaded bone morphogenetic protein-2 (BMP-2/MPEG-PCL-MS) to effectively solve the problem mentioned above, prolong its reaction time at the targeted site, and avoid the pain of patients caused by frequent administration. The physicochemical properties and in vitro release behaviors were good. The microspheres showed high biocompatibility and strongly induced osteogenesis in vivo. BMP-2/MPEG-PCL-MS has been proven to exert sustained-release in vivo and maintain the inherent BMP-2 activity. They can be directly injected into the bone defect site, or implanted to a large bone defect site together with stent material to exert therapeutic effects. Hence, this smart drug delivery system has promising potential for clinical applications and provides a well-controlled design for combination of tissue engineering and pharmaceutics for further exploration.


Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Osso e Ossos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Animais , Materiais Biocompatíveis , Proteína Morfogenética Óssea 2/administração & dosagem , Proteína Morfogenética Óssea 2/química , Osso e Ossos/diagnóstico por imagem , Linhagem Celular , Preparações de Ação Retardada , Composição de Medicamentos , Liberação Controlada de Fármacos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/tratamento farmacológico , Humanos , Camundongos , Microesferas , Poliésteres , Polietilenoglicóis , Microtomografia por Raio-X
6.
Comput Methods Programs Biomed ; 193: 105493, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32408237

RESUMO

BACKGROUND AND OBJECTIVE: Although nanoparticle preparations have great potential in the treatment of tumors, nanoparticle preparations have not achieved the desired therapeutic effect. The reason is that the abnormal tumor microenvironment prevents nanoparticles from effective concentrating and reaching tumor area. Therefore, it's very necessary to better understand the effect of the abnormal tumor microenvironment on the transvascular transport of nanoparticles to overcome this critical problem. METHODS: In this paper, a tumor abnormal vascular-interstitial model was established, and the transvascular transport process of nanoparticles was simulated in the model by computational fluid dynamics (CFD) modeling. RESULTS: The simulation results showed that the transport efficiency of nanoparticles decreased with increasing interstitial fluid pressure (IFP), and nanoparticles could not cross the blood vessel wall when the IFP approached the blood vessel wall pressure. Interestingly, the transport efficiency of nanoparticles first increased with blood flow velocity, and then decreased with blood flow velocity. CONCLUSIONS: The results showed that with the continuous malignant development of tumors, the ability of nanoparticles to passively diffuse has almost disappeared. The enhanced permeability and retention (EPR) effect of the nanoparticles disappeared with the disappearance of the pressure gradient inside the tumor. These results provided guidance for future research on the vascular transport pathways and mechanisms of nanoparticles.


Assuntos
Nanopartículas , Neoplasias , Velocidade do Fluxo Sanguíneo , Simulação por Computador , Líquido Extracelular , Humanos , Neoplasias/tratamento farmacológico , Microambiente Tumoral
7.
Opt Express ; 26(14): 17964-17976, 2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-30114078

RESUMO

We systematically investigate the data analysis methods in terahertz frequency domain spectroscopy (THz-FDS) with coherent detection. We demonstrate that the Hilbert transform method is one of the most appropriate for data processing in THz-FDS. By converting frequency-domain signal into time domain with further data processing, the system noise due to Fabry-Pérot (FP) interference is greatly restrained. Accurate permittivity of lactose monohydrate is successfully extracted under the condition of the existence of atmospheric water vapor. Our work greatly promotes the development of THz spectroscopy in practical applications.

8.
Opt Express ; 26(6): 7107-7116, 2018 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-29609397

RESUMO

We demonstrate generation of 0.2 mJ terahertz (THz) pulses in lithium niobate driven by Ti:sapphire laser pulses at room temperature. Employing tilted pulse front technique, the 800 nm-to-THz energy conversion efficiency has been optimized to 0.3% through chirping the sub-50 fs pump laser pulses to overcome multi-photon absorption and to extend effective interaction length for phase matching. Our approach paves the way for mJ-level THz generation via optical rectification using existing Ti:sapphire laser systems which can deliver Joule-level pulse energy with sub-50 fs pulse duration.

9.
Zhonghua Nan Ke Xue ; 19(8): 732-5, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24010210

RESUMO

OBJECTIVE: To evaluate the clinical efficacy of bladder gasification and stasis dispersion combined with antibiotic therapy in the treatment of III A chronic prostatitis. METHODS: We conducted a randomized controlled clinical study on 120 III A prostatitis patients that all met the diagnostic criteria. We divided the patients into groups A, B and C of equal number to receive oral medication of sparfloxacin, sparfloxacin + tamsulosin, and sparfloxacin + herbal decoction, respectively, all for a course of 4 weeks. We evaluated the primary therapeutic indexes according to the total scores of the patients on traditional Chinese medicine (TCM) syndrome and NIH-CPSI and the secondary therapeutic indexes based on the count of white blood cells (WBC) in the expressed prostatic secretion (EPS). RESULTS: After treatment, the total scores on TCM syndrome and NIH-CPSI were significantly reduced in groups B (42.15 +/- 10.29 and 13.25 +/- 6.04) and C (41.26 +/- 11.25 and 12.38 +/- 7.19) than in A (49.43 +/- 11.09 and 17.62 +/- 5.84) ( P < 0.05), and so was the WBC count in EPS in group C (7.76 +/- 15.73) than in groups A (11.45 +/- 10.33) and B (12.28 +/- 13.81) (P < 0.05). The difference between pre- and post-treatment scores on TCM syndrome was more significant in group C (12.65 +/- 11.76) than in B (8.55 +/- 10.15) (P < 0.05). CONCLUSION: Bladder gasification and stasis dispersion combined with antibiotic therapy is effective for the treatment of III A chronic prostatitis, and therefore deserves wide clinical application.


Assuntos
Antibacterianos/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Fitoterapia , Prostatite/tratamento farmacológico , Adulto , Doença Crônica , Terapia Combinada , Humanos , Masculino , Medicina Tradicional Chinesa , Prostatite/classificação , Resultado do Tratamento
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