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1.
Front Chem ; 10: 1037995, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36311437

RESUMO

The zinc metal anode is the most promising metal anode material in aqueous battery systems due to its low cost and high theoretical capacity. However, it still undergoes irreversible reactions such as premature failure of the dendrites/dead Zn during Zn stripping/plating, resulting in the inferior cycling stability of the Zn-based full cell. Here, we demonstrate a facile 3D-Cu alloy coating to improve Zn reversibility by providing spatial voids to accommodate the plated Zn to form dendrite-free morphology. Combining the larger 3D surface and the alloying-dealloying process, the Zn anode reactions exhibit enhanced reaction kinetics to meet large operating current densities. The 3D-Cu-coated Zn anode can deliver improved cycling stability for 350 h under a large areal capacity of 3 mAh cm-2. It also enables MnO2-Zn at the full cell level to achieve a specific capacity of 205 mAh g-1 and longer cycling for 350 cycles with 87.4% retention of the initial capacity. This research provides a new pathway to achieve high reversible Zn metal chemistry.

2.
Theranostics ; 11(20): 10001-10011, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34815800

RESUMO

Rationale: Glucose oxidase (GOx)-based biocatalytic nanoreactors can cut off the energy supply of tumors for starvation therapy and deoxygenation-activated chemotherapy. However, these nanoreactors, including mesoporous silica, calcium phosphate, metal-organic framework, or polymer nanocarriers, cannot completely block the reaction of GOx with glucose in the blood, inducing systemic toxicity from hydrogen peroxide (H2O2) and anoxia. The low enzyme loading capacity can reduce systemic toxicity but limits its therapeutic effect. Here, we describe a real 'ON/OFF' intelligent nanoreactor with a core-shell structure (GOx + tirazapamine (TPZ))/ZIF-8@ZIF-8 modified with the red cell membrane (GTZ@Z-RBM) for cargo delivery. Methods: GTZ@Z-RBM nanoparticles (NPs) were prepared by the co-precipitation and epitaxial growth process under mild conditions. The core-shell structure loaded with GOx and TPZ was characterized for hydrate particle size and surface charge. The GTZ@Z-RBM NPs morphology, drug, and GOx loading/releasing abilities, system toxicity, multimodal synergistic therapy, and tumor metastasis suppression were investigated. The in vitro and in vivo outcomes of GTZ@Z-RBM NPs were assessed in 4T1 breast cancer cells. Results: GTZ@Z-RBM NPs could spatially isolate the enzyme from glucose in a physiological environment, reducing systemic toxicity. The fabricated nanoreactor with high enzyme loading capacity and good biocompatibility could deliver GOx and TPZ to the tumors, thereby exhausting glucose, generating H2O2, and aggravating hypoxic microenvironment for starvation therapy, DNA damage, and deoxygenation-activated chemotherapy. Significantly, the synergistic therapy effectively suppressed the breast cancer metastasis in mice and prolonged life without systemic toxicity. The in vitro and in vivo results provided evidence that our biomimetic nanoreactor had a powerful synergistic cascade effect in treating breast cancer. Conclusion: GTZ@Z-RBM NPs can be used as an 'ON/OFF' intelligent nanoreactor to deliver GOx and TPZ for multimodal synergistic therapy and tumor metastasis suppression.


Assuntos
Glucose Oxidase/farmacologia , Sistemas de Liberação de Fármacos por Nanopartículas/farmacologia , Nanotecnologia/métodos , Animais , Biomimética , Linhagem Celular Tumoral , China , Terapia Combinada , Feminino , Glucose Oxidase/administração & dosagem , Concentração de Íons de Hidrogênio , Camundongos , Nanopartículas/química , Neoplasias/tratamento farmacológico , Tirapazamina/administração & dosagem , Tirapazamina/farmacologia , Microambiente Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
3.
Nanotechnology ; 33(2)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34571495

RESUMO

We developed a rapid synthesis method for monodispersed Au-Ag alloy nanosponges (NSs) with high density of 'hotspots' for near-infrared surface enhanced Raman scattering (NIR-SERS) by a selective laser-irradiation melting and chemical dealloying process. Au@Ag core-shell nanocubes were firstin situconverted into solid alloyed Au-Ag nanospheres by a rapid laser irradiation igniting quick fusion and quenching process within two minutes. The alloyed Au-Ag nanospheres transformed into Au-Ag alloy NSs after treated by a chemical dealloying process. Different from traditional thermal annealing, it thus can effectively avoid the heat fusion between nanoparticles, and maintain the alloyed Au-Ag nanospheres and NSs in high monodispersity. Importantly, due to the strong plasmonic coupling in nanopores (pore size less than 10 nm), the obtained Au-Ag alloy NSs show a broad and intense localized surface plasmon resonances absorption ranging from visible to near-Infrared region (500-1200 nm). The accessibly open structures for absorbing targets and high-density of 'NIR-hotspots' endow the Au-Ag alloy NSs substrate with superior sensitivity in NIR-SERS detection of 4-aminothiophenol with an enhancement factor of ∼107. This work not only provides a simple pathway for rapid preparation of NIR-SERS substrate for biosensing, but also might open up a new horizon for fabricating spongy nanostructures with other elements.

4.
Sci Rep ; 11(1): 16322, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381144

RESUMO

Neuroimaging studies have documented brain structural alterations induced by chronic pain, particularly in gray matter volume. However, the effects of trigeminal neuralgia (TN), a severe paroxysmal pain disorder, on cortical morphology are not yet known. In this study, we recruited 30 TN patients and 30 age-, and gender-matched healthy controls (HCs). Using Computational Anatomy Toolbox (CAT12), we calculated and compared group differences in cortical thickness, gyrification, and sulcal depth with two-sample t tests (p < 0.05, multiple comparison corrected). Relationships between altered cortical characteristics and pain intensity were investigated with correlation analysis. Compared to HCs, TN patients exhibited significantly decreased cortical thickness in the left inferior frontal, and left medial orbitofrontal cortex; decreased gyrification in the left superior frontal cortex; and decreased sulcal depth in the bilateral superior frontal (extending to anterior cingulate) cortex. In addition, we found significantly negative correlations between the mean cortical thickness in left medial orbitofrontal cortex and pain intensity, and between the mean gyrification in left superior frontal cortex and pain intensity. Chronic pain may be associated with abnormal cortical thickness, gyrification and sulcal depth in trigeminal neuralgia. These morphological changes might contribute to understand the underlying neurobiological mechanism of trigeminal neuralgia.


Assuntos
Córtex Cerebral/fisiopatologia , Neuralgia do Trigêmeo/fisiopatologia , Dor Crônica/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade
5.
Eye Sci ; 26(3): 173-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21913351

RESUMO

PURPOSE: To preliminarily investigate the application value of rapid sequences FFE and SSh-TSE in ocular magnetic resonance imaging (MRI). METHODS: Ocular MRI was performed in 18 subjects without ocular conditions,and demonstration of 15 delicate anatomic structures on two sequences in each subject was rated by three proficient physicians. RESULTS: FFE sequence was comparatively advantageous in demonstrating delicate structures on ocular wall and ocular adnexa (P<0.001) over SSh-TSE; while SSh-TSE sequence better revealed the delicate anatomy within anterior chamber (P<0.001) and optic nerve sheath (P<0.05), with statistically significant differences compared with FFE. CONCLUSION: Optimized FFE and SSh-TSE sequences are able to effectively eliminate the impact from motion artifact and thus result in desirable images with high spatial resolution. The application of high-resolution MR microscopic imaging technique has improved the ability to demonstrate delicate ocular structures.


Assuntos
Imageamento por Ressonância Magnética/métodos , Bainha de Mielina/fisiologia , Nervo Óptico/fisiologia , Artefatos , Feminino , Humanos , Movimento , Projetos Piloto
6.
Nan Fang Yi Ke Da Xue Xue Bao ; 29(11): 2197-200, 2009 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19923065

RESUMO

OBJECTIVE: To analyze the correlation between the perfusion data and microvessel density (MVD) in ovarian tumors, and investigate the hemodynamic features of the tumors in terms of anatomy and functional CT imaging. METHODS: Six patients with surgically confirmed benign ovarian tumors and 6 with malignant ovarian tumors underwent multi-slice CT perfusion imaging to acquire the perfusion parameters including perfusion, PEI, TTP, BV peak enhancement image(PEI), time to peak(TTP) and blood volume(BV). The tumors were stained and counted by Immunohistochemical staining of the microvessels in the tumor was performed to detect the MVD. RESULTS: s The time-density curves of the benign ovarian tumors increased slowly, reaching the peak at 40 s; the curves of the malignant tumors rose rapidly and continuously and reached the peak at 25 s. The differences in the perfusion data (PEI, TTP, BV) were statistically significant between the benign and malignant tumors (P<0.05). The MVD of the malignant tumors was significantly greater than that of the benign tumors (P<0.05). The mean BV of the malignant ovarian tumor was positively correlated to MVD (r=0.786, P<0.05). CONCLUSION: Multi-slice spiral CT perfusion imaging can provide accurate enhancement data of the ovarian tumors and helps in the diagnosis and differential diagnosis of the ovarian tumors by presenting the changes of the hemodynamic features in the tumors.


Assuntos
Neoplasias Ovarianas/irrigação sanguínea , Neoplasias Ovarianas/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Adulto , Idoso , Capilares/patologia , Cistadenocarcinoma/irrigação sanguínea , Cistadenocarcinoma/diagnóstico por imagem , Feminino , Fibroma/irrigação sanguínea , Fibroma/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade
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