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1.
Chemistry ; 30(22): e202304252, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38369896

RESUMO

Ta-doped Li7La3Zr2O12 (LLZTO) solid-state electrolytes (SEs) show great promise for solid-state batteries due to its high conductivity and safety. However, one of the challenges it faces is lithium dendrite propagation upon long-term cycling. To address this issue, we propose the incorporation of fumed silica (FS) at the grain boundaries of LLZTO to modify the properties of the garnet pellet, which effectively inhibits the dendrite growth. The introduction of FS has demonstrated several beneficial effects. Firstly, it reduces the migration barrier of lithium ions, which helps prevent dendrite formation and propagation. Additionally, FS reduces the electronic conductivity of the SEs pellet, suppressing the dendrite formation. Moreover, the formed lithium silicates from FS might also be acted as electron inhibitor, thus inhibiting the lithium dendrite growth upon cycling. By investigating the use of FS as a modifier in LLZTO-based electrolytes, our study contributes to advancing dendrite-free solid-state electrolytes and thus the development of high-performance all-solid-state batteries.

2.
Phys Chem Chem Phys ; 26(7): 6037-6048, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38295373

RESUMO

Porous carbons (PCs) have been widely investigated as electrode materials for supercapacitors. However, during the preparation process, intense pore formation reactions result in an amorphous carbon structure, which limits the rate performance of the electrode material. Herein, coal is chosen as a carbon source and making use of different reaction characteristics of vitrinite and inertinite with a KOH activator, an interconnected porous structure carbon material with an abundant graphite microcrystalline structure is obtained; the organic relationships between the ratio of vitrinite and inertinite, carbonization conditions, material structure and capacity performance were researched. At the ratio of vitrinite to inertinite of 1 : 2, the sample shows a specific surface area of 2507 m2 g-1 and its ID1/IG is 1.31, which is lower than that of raw coal (1.36). Due to the synergistic effect of the pore structure and graphite microcrystals, PC-900-40 exhibits an improved specific capacitance of 229.40 F g-1 at a current density of 1.0 A g-1, and even at a high current density of 10.0 A g-1 it delivers a specific capacitance of 170.04 F g-1. The PC-900-40//PC-900-40 symmetrical capacitor retains 96% of its initial capacitance after 20 000 cycles.

3.
Int J Mol Sci ; 23(3)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35163033

RESUMO

In conifers, somatic embryogenesis is uniquely initiated from immature embryos in a narrow time window, which is considerably hindered by the difficulty to induce embryogenic tissue (ET) from other tissues, including mature somatic embryos. In this study, the embryogenic ability of newly induced ET and DNA methylation levels was detected, and whole-transcriptome sequencing analyses were carried out. The results showed that ultra-low temperature treatment significantly enhanced ET induction from mature somatic embryos, with the induction rate from 0.4% to 15.5%, but the underlying mechanisms remain unclear. The newly induced ET showed higher capability in generating mature embryos than the original ET. DNA methylation levels fluctuated during the ET induction process. Here, WGCNA analysis revealed that OPT4, TIP1-1, Chi I, GASA5, GST, LAX3, WRKY7, MYBS3, LRR-RLK, PBL7, and WIN1 genes are involved in stress response and auxin signal transduction. Through co-expression analysis, lncRNAs MSTRG.505746.1, MSTRG.1070680.1, and MSTRG.33602.1 might bind to pre-novel_miR_339 to promote the expression of WRKY7 genes for stress response; LAX3 could be protected by lncRNAs MSTRG.1070680.1 and MSTRG.33602.1 via serving as sponges for novel_miR_495 to initiate auxin signal transduction; lncRNAs MSTRG.505746.1, MSTRG.1070680.1, and MSTRG.33602.1 might serve as sponges for novel_miR_527 to enhance the expression of Chi I for early somatic embryo development. This study provides new insight into the area of stress-enhanced early somatic embryogenesis in conifers, which is also attributable to practical applications.


Assuntos
Criopreservação/métodos , MicroRNAs/genética , Picea/embriologia , Picea/genética , Proteínas de Plantas/metabolismo , RNA Longo não Codificante/genética , RNA Mensageiro/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Picea/metabolismo , Proteínas de Plantas/genética , Técnicas de Embriogênese Somática de Plantas , RNA Mensageiro/genética
4.
Angew Chem Int Ed Engl ; 61(10): e202114789, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34939320

RESUMO

Artificial interfaces can alleviate the side reactions and the formation of the metallic (e.g., Li, Na, and Zn) dendrites. However, the traditional ones always breakdown during the repeated plating/stripping and fail to regulate the electrodeposition behaviors of the electrodes. Herein, a self-healable ion regulator (SIR) is designed as a desolvation shield to protect the Zn electrodes and guide the Zn electrodeposition. Benefiting from the intermolecular hydrogen bonds, SIR shows a superb capability to in situ repair the plating/stripping-induced cracks. Besides, the results of theoretical calculations and electrochemical characterizations show that the coating reduces water molecules in the solvated sheath of hydrated Zn2+ and restrains the random Zn2+ diffusion on the Zn surface. Even with a coating layer of only 360 nm, the SIR-modified Zn electrode exhibits excellent long-term stability for >3500 h at 2 mAh cm-2 and >950 h at an ultrahigh areal capacity of 20 mAh cm-2 .

5.
Analyst ; 146(4): 1340-1345, 2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33367331

RESUMO

Prostate specific antigen (PSA) has been considered as the most potential serological biomarker for the early stage detection of prostate cancer. Here, a label-free fluorescence aptasensing strategy for detecting PSA based on hybridization chain reaction (HCR) and G-quadruplex DNAzymes has been developed. This designed strategy consists of three DNA probes, aptamer probe (AP), hairpin probe 1 (H1) and hairpin probe 2 (H2). In the presence of target PSA, the aptamer sequences in AP specifically recognized PSA to form a PSA-aptamer complex, causing an AP conformation change and thus releasing the initiator, which triggered the chain-like assembly of H1 and H2 that yielded extended nicked double-stranded DNA through HCR. Upon the addition of hemin, the G-rich segments at the end of H1 and H2 self-assembled into the peroxidase-mimicking hemin/G-quadruplex DNAzymes, which catalyzed the hydrogen peroxide-mediated oxidation of thiamine to give a fluorescence signal dependent on the concentration of PSA. Under optimal conditions, a limit of detection of 0.05 nM and a linear range from 0.1 nM to 1 nM (R2 = 0.9942) were achieved by this assay. In addition, other interfering proteins, such as IgG, AFP and CEA, did not produce any significant change in the fluorescence intensity response, indicating good selectivity of this sensor for PSA detection. Finally, this proposed aptasensor was successfully used for diluted serum samples.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , DNA Catalítico , Quadruplex G , Humanos , Limite de Detecção , Masculino , Antígeno Prostático Específico
6.
Inorg Chem ; 60(5): 3015-3024, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33577307

RESUMO

Trace doping is an efficient way to improve the stability of nickel-rich layered cathodes for lithium-ion batteries, but the structural origin of such improvement, rather than a simple replacement, has been rarely explored. Herein, Ga dopants have been introduced into a nickel-rich host, LiNi0.9Co0.1O2, by a combination of coprecipitation and the solid-state sintering method. Structural analyses based on high-resolution synchrotron powder diffraction data and X-ray absorption spectra suggest that Ga preferentially sits in the NiO6 slabs, resulting in reduced Ni/Li cationic mixing and depressed lattice vibration. Due to the smaller dissociation energy of Ga-O bonds, some Ga3+ cations migrate first toward Li layers upon delithiation and form the GaO4 tetrahedral symmetry irreversibly during the electrochemical process, which acts as a pillar in the subsequent electrochemical processes. As a result, the doped material exhibits both improved cycling performance and rate capability under a high operating voltage (4.5 V) due to the stabilized structure in the lithiation/delithiation process. This study illustrates how a dopant enhances the electrochemical stability in views of both pristine and charged structure and suggests that a positive effect is expected from the dopant favoring the tetrahedral symmetry (e.g., Al).

7.
Pharmacol Res ; 159: 105031, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32562816

RESUMO

Thrombosis initiated by abnormal platelet aggregation is a pivotal pathological event that precedes most cases of cardiovascular diseases (CVD). Recently, growing evidence indicates that platelet could be a potential target for CVD prevention. However, as the conventional antithrombotic management strategy, applications of current antiplatelet agents are somewhat limited by their various side effects, such as bleeding risk and drug resistance. Hence, efforts have been made to search for agents as complementary therapies. Ginsenoside, the principal active component extracted from Panax ginseng, has gained much attention for its regulations on multiple crucial events of platelet aggregation. From structural characteristics to clinical applications, this review anatomized the intrinsic structure-function relationship of antiplatelet potency of ginsenosides, and the involved signal pathways were specifically summarized. Additionally, the emphasis was placed on clinical studies that investigate the antithrombotic efficacy of ginsenosides in the treatment of CVD. Further, a broad overview of approaches for improving the bioavailability of ginsenosides was concluded. Limitations and prospects of current studies were also discussed. This study may provide some new insights into the systematic understanding of ginsenosides in CVD treatment and lay a foundation for future research.


Assuntos
Plaquetas/efeitos dos fármacos , Fármacos Cardiovasculares/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Ginsenosídeos/uso terapêutico , Músculo Liso Vascular/efeitos dos fármacos , Neointima , Inibidores da Agregação Plaquetária/uso terapêutico , Agregação Plaquetária/efeitos dos fármacos , Remodelação Vascular/efeitos dos fármacos , Animais , Disponibilidade Biológica , Plaquetas/metabolismo , Fármacos Cardiovasculares/efeitos adversos , Fármacos Cardiovasculares/farmacocinética , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/patologia , Ginsenosídeos/efeitos adversos , Ginsenosídeos/farmacocinética , Humanos , Estrutura Molecular , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Inibidores da Agregação Plaquetária/efeitos adversos , Inibidores da Agregação Plaquetária/farmacocinética , Transdução de Sinais , Relação Estrutura-Atividade
8.
Physiol Plant ; 170(4): 569-579, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32840878

RESUMO

Tomato is one of the most popular horticultural crops, and many commercial tomato cultivars are particularly susceptible to Botrytis cinerea. Non-expressor of pathogenesis-related gene 1 (NPR1) is a critical component of the plant defense mechanisms. However, our understanding of how SlNPR1 influences disease resistance in tomato is still limited. In this study, two independent slnpr1 mutants were used to study the role of SlNPR1 in tomato resistance against B. cinerea. Compared to (WT), slnpr1 leaves exhibited enhanced resistance against B. cinerea with smaller lesion sizes, higher activities of chitinase (CHI), ß-1, 3-glucanases (GLU) and phenylalanine ammonia-lyase (PAL), and significantly increased expressions of pathogenesis-related genes (PRs). The increased activities of peroxidase (POD), ascorbate peroxidase (APX) and decreased catalase (CAT) activities collectively regulated reactive oxygen species (ROS) homeostasis in slnpr1 mutants. The integrity of the cell wall in slnpr1 mutants was maintained. Moreover, the enhanced resistance was further reflected by induction of defense genes involved in jasmonic acid (JA) and ethylene (ET) signaling pathways. Taken together, these findings revealed that knocking out SlNPR1 resulted in increased activities of defense enzymes, changes in ROS homeostasis and integrity of cell walls, and activation of JA and ET pathways, which confers resistance against B. cinerea in tomato plants.


Assuntos
Solanum lycopersicum , Botrytis , Ciclopentanos , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Técnicas de Inativação de Genes , Homeostase , Humanos , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Oxilipinas , Doenças das Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo
9.
BMC Plant Biol ; 19(1): 354, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31412779

RESUMO

BACKGROUND: High temperature is a major environmental stress that limits plant growth and agriculture productivity. Mitogen-activated protein kinases (MAPKs) are highly conserved serine and threonine protein kinases that participate in response to diverse environmental stresses in plants. A total of 16 putative SlMAPK genes are identified in tomato, and SlMAPK3 is one of the most extensively studied SlMAPKs. However, the role of SlMAPK3 in response to heat stress is not clearly understood in tomato plants. In this study, we performed functional analysis of SlMAPK3 for its possible role in response to heat stress. RESULTS: qRT-PCR analyses revealed that SlMAPK3 relative expression was depressed by heat stress. Here, wild-type (WT) tomato plants and CRISPR/Cas9-mediated slmapk3 mutant lines (L8 and L13) were used to investigate the function of SlMAPK3 in response to heat stress. Compared with WT plants, slmapk3 mutants exhibited less severe wilting and less membrane damage, showed lower reactive oxygen species (ROS) contents, and presented higher both activities and transcript levels of antioxidant enzymes, as well as elevated expressions of genes encoding heat stress transcription factors (HSFs) and heat shock proteins (HSPs). CONCLUSIONS: CRISPR/Cas9-mediated slmapk3 mutants exhibited more tolerance to heat stress than WT plants, suggesting that SlMAPK3 was a negative regulator of thermotolerance. Moreover, antioxidant enzymes and HSPs/HSFs genes expression were involved in SlMAPK3-mediated heat stress response in tomato plants.


Assuntos
Resposta ao Choque Térmico/genética , Proteínas de Plantas/genética , Espécies Reativas de Oxigênio/metabolismo , Solanum lycopersicum/genética , Antioxidantes/metabolismo , Técnicas de Inativação de Genes , Homeostase , Solanum lycopersicum/metabolismo , Proteínas de Plantas/metabolismo
10.
BMC Plant Biol ; 19(1): 38, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30669982

RESUMO

BACKGROUND: NPR1, nonexpressor of pathogenesis-related gene 1, is a master regulator involved in plant defense response to pathogens, and its regulatory mechanism in the defense pathway has been relatively clear. However, information about the function of NPR1 in plant response to abiotic stress is still limited. Tomato is the fourth most economically crop worldwide and also one of the best-characterized model plants employed in genetic studies. Because of the lack of a stable tomato NPR1 (SlNPR1) mutant, little is known about the function of SlNPR1 in tomato response to biotic and abiotic stresses. RESULTS: Here we isolated SlNPR1 from tomato 'Ailsa Craig' and generated slnpr1 mutants using the CRISPR/Cas9 system. Analysis of the cis-acting elements indicated that SlNPR1 might be involved in tomato plant response to drought stress. Expression pattern analysis showed that SlNPR1 was expressed in all plant tissues, and it was strongly induced by drought stress. Thus, we investigated the function of SlNPR1 in tomato-plant drought tolerance. Results showed that slnpr1 mutants exhibited reduced drought tolerance with increased stomatal aperture, higher electrolytic leakage, malondialdehyde (MDA) and hydrogen peroxide (H2O2) levels, and lower activity levels of antioxidant enzymes, compared to wild type (WT) plants. The reduced drought tolerance of slnpr1 mutants was further reflected by the down-regulated expression of drought related key genes, including SlGST, SlDHN, and SlDREB. CONCLUSIONS: Collectively, the data suggest that SlNPR1 is involved in regulating tomato plant drought response. These results aid in further understanding the molecular basis underlying SlNPR1 mediation of tomato drought sensitivity.


Assuntos
Secas , Genes de Plantas , Solanum lycopersicum/genética , Adaptação Fisiológica/genética , Sistemas CRISPR-Cas , Solanum lycopersicum/fisiologia , Mutagênese , Estresse Fisiológico/genética
11.
Planta ; 250(2): 643-655, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31144110

RESUMO

MAIN CONCLUSION: Trehalose increased drought tolerance of tomato plants, accompanied by reduced water loss and closed stomata, which was associated with the upregulated ABA signaling-related genes expression, but not in ABA accumulation. Drought is one of the principal abiotic stresses that negatively influence the growth of plant and yield. Trehalose has great agronomic potential to improve the stress tolerance of plants. However, little information is available on the role of ABA and its signaling components in trehalose-induced drought tolerance. The aim of this study is to elucidate the potential mechanism by which trehalose regulates ABA in response to drought stress. In this study, 6-week-old tomato (Solanum lycopersicum cv. Ailsa Craig) plants were treated with 0 or 15.0 mM trehalose solution. Results showed that trehalose treatment significantly enhanced drought tolerance of tomato plants, accompanied by encouraged stomatal closure and protected chloroplast ultrastructure. Compared with controls, trehalose-treated plants showed lower hydrogen peroxide content and higher antioxidant enzymes activities, which contributed to alleviate oxidative damage caused by drought. Moreover, trehalose treatment decreased ABA content, which was followed by the downregulation of ABA biosynthesis genes expression and the upregulation of ABA catabolism genes expression. In contrast, exogenous trehalose upregulated transcript levels of ABA signaling-related genes, including SlPYL1/3/4/5/6/7/9, SlSnRK2.3/4, SlAREB1/2, and SlDREB1. These results suggested that trehalose treatment enhanced drought tolerance of tomato plants, and it's ABA signaling rather than ABA metabolism that was involved in trehalose-induced drought tolerance in tomato plants. These findings provide evidence for the physiological role of trehalose and bring about a new understanding of the possible relationship between trehalose and ABA.


Assuntos
Ácido Abscísico/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Transdução de Sinais , Solanum lycopersicum/fisiologia , Trealose/farmacologia , Cloroplastos/fisiologia , Cloroplastos/ultraestrutura , Secas , Solanum lycopersicum/genética , Solanum lycopersicum/ultraestrutura , Fenótipo , Proteínas de Plantas/genética , Estômatos de Plantas/genética , Estômatos de Plantas/fisiologia , Estômatos de Plantas/ultraestrutura , Estresse Fisiológico
12.
Opt Express ; 27(21): 30798-30809, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31684323

RESUMO

Ultrashort laser pulses, featuring remarkable spectral tunability, are highly demanded for nonlinear light-matter interactions in a variety of molecules. Here, we report on the generation of soliton-plasma-driven ultrashort pulses with both bandwidth- and wavelength-tunability in the visible spectral region. Using He-filled single-ring photonic crystal fiber (SR-PCF), we demonstrate in the experiments that the spectral bandwidths of blueshifting solitons can be manipulated by adjusting the input pulse energy, gas pressure and core diameter of the SR-PCF, while the central wavelengths of these solitons can be continuously tuned over 200 nm. We found that in a large-core SR-PCF (24.6-µm core diameter), the bandwidths of blueshifting solitons can be effectively broaden to near 100 nm, pointing out the possibility of generating few-cycle, wavelength-tunable visible pulses using this set-up. In addition, we observed in the experiments that in a small-core SR-PCF (with a core diameter of 17 µm), the blueshifting solitons show little residual light near the pump wavelength, resulting in a high-efficiency frequency up-conversion process. These experimental results, confirmed by numerical simulations, pave the way to a new generation of compact, ultrashort light sources with excellent tunability at visible wavelengths, which may have many applications in the fields of time-resolved spectroscopy and ultrafast nonlinear optics.

13.
Bull Environ Contam Toxicol ; 102(3): 432-438, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30726510

RESUMO

The washed and unwashed current (C) and previous year (C + 1) needles, branches and top soils of Pinus tabulaeformis trees were sampled at five sites Haitai industrial district (HT), Puji River (PJ), Fukang road (FK), Residential area (RA) and Baxian Mountain (BX) in Tianjin along an urban-rural gradient and analyzed for heavy metals (Cu, Mn, Zn, Pb and Cd) concentrations via ICP. C + 1 needles generally had higher Mn, Pb, Cd than C needles while the opposite was for Cu and Zn. Total Cu, Zn, Pb, Cd in soils peaked at HT and decreased at RA and BX. Heavy metals were generally higher in the unwashed needles than the washed needles at all sites. Meanwhile MDA, soluble sugar and free proline concentration in needles were increased with the increasing of heavy metal contents along the urban-rural gradient, further correlated with the heavy metal contents.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Metais Pesados/análise , Pinus/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Urbanização , China , Pinus/química , Folhas de Planta/química
14.
Bioconjug Chem ; 29(10): 3495-3502, 2018 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-30252441

RESUMO

The nanocarrier-based delivery system has emerged as a promising candidate for cancer therapy; nevertheless, their quality problems, variation between batches, and carrier-related toxicity issues have restricted their clinical utilization. Compared with traditional carrier-based nanoparticles, carrier-free nanodrug delivery systems preferred to overcome all these drawbacks and will have a wide range of applications in biomedicine and nanotechnology. Herein, we developed a novel carrier-free nanodrug Asp-UA consisted of the classical drug aspirin and the natural plant drug UA via a green and simple approach. The Asp-UA NPs were investigated for shape, particle size, zeta potential, stability, and UV-vis spectroscopy absorption. Cellular uptake study showed that Asp-UA NPs could be easily internalized by HepG2 cells; cellular study demonstrated that Asp-UA NPs held better inhibitory efficiency on tumor metastasis with low toxicity in vitro and in vivo. Moreover, Asp-UA NPs could obviously suppress the progress of cancer metastasis by H22 cells in vivo. Overall, Asp-UA NPs possess a variety of advantages and hold promise to become an alternative to the treatment of cancer metastasis.


Assuntos
Antineoplásicos/uso terapêutico , Nanopartículas , Metástase Neoplásica/tratamento farmacológico , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Aspirina/administração & dosagem , Linhagem Celular Tumoral , Portadores de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Estabilidade de Medicamentos , Humanos , Masculino , Camundongos , Compostos Fitoquímicos/administração & dosagem
15.
Opt Express ; 26(26): 34977-34993, 2018 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-30650913

RESUMO

We numerically investigate the generation of wavelength-tunable few-cycle pulses in the visible spectral region through soliton-plasma interactions. We found that in a He-filled single-ring photonic crystal fiber (SR-PCF), soliton-plasma interactions could shift the optical spectra of pulses propagating in the fiber to shorter wavelengths. Through adjusting the single pulse energy launched into the fiber, the central wavelength of these blueshifting pulses could be continuously tuned over hundreds of nanometers, while maintaining a high energy conversion efficiency of >57%. Moreover, we observed that during the nonlinear pulse propagation in the SR-PCF, soliton self-compression effects enhanced the plasma density in the fiber at high pulse energies, which could modulate the phase-matching condition of ultraviolet (UV) dispersive wave (DW) generation. Furthermore, we employed the recently-developed model to study numerically the loss and dispersion of the SR-PCF in its resonant and anti-resonant spectral regions, and demonstrated the remarkable influence of the core-cladding resonance on the process of soliton-plasma interactions. The numerical results demonstrated here pave the way to develop wavelength-tunable, few-cycle light sources in the visible region, which may have considerable application potential in pump-probe spectroscopy and strong-field physics.

16.
Opt Lett ; 43(9): 2197-2200, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29714788

RESUMO

A carrier-envelope-phase-stable near-single-cycle mid-infrared laser based on optical parametric chirped pulse amplification and hollow-core fiber compression is demonstrated. A 4 µm laser pulse with 11.8 mJ energy is delivered from a KTA-based optical parametric chirped pulse amplification (OPCPA) with 100 Hz repetition rate, and compressed to 105 fs by a two-grating compressor with efficiency over 50%. Subsequently, the pulse spectrum is broadened by employing a krypton gas-filled hollow-core fiber. Then, the pulse duration is further compressed to 21.5 fs through a CaF2 bulk material with energy of 2.6 mJ and energy stability of 0.9% RMS, which is about 1.6 cycles for a 4 µm laser pulse. The carrier envelope phase of the near-single-cycle 4 µm laser pulse is passively stabilized with 370 mrad.

17.
Mol Pharm ; 15(6): 2466-2478, 2018 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-29727577

RESUMO

Ursolic acid (UA) is a food-plant-derived natural product which has good anticancer activities and low toxicity. However, the poor water solubility of UA limits its application in clinic. To address this issue, we developed a carrier-free nanodrug by self-assembly of UA. Here, we showed that UA nanoparticles (NPs) have a near-spherical shape with a diameter of ∼150 nm. UA NPs exhibited higher antiproliferative activity; significantly caused apoptosis; decreased the expression of COX-2/VEGFR2/VEGFA; and increased the immunostimulatory activity of TNF-α, IL-6, and IFN-ß and decreased the activity of STAT-3 in A549 cells in vitro. Furthermore, UA NPs could inhibit tumor growth and have the ability of liver protection in vivo. More importantly, UA NPs could significantly improve the activation of CD4+ T-cells, which indicated that UA NPs have the potential for immunotherapy. Overall, a carrier-free UA nanodrug may be a promising drug to further enhance their anticancer efficacy and immune function.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Imunoterapia/métodos , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Triterpenos/administração & dosagem , Células A549 , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Desenho de Fármacos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias/imunologia , Neoplasias/patologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Triterpenos/química , Triterpenos/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , Ácido Ursólico
18.
Nanomedicine ; 14(2): 227-236, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29128661

RESUMO

Ursolic acid (UA), a natural triterpene acid, is a promising anti-cancer drug due to its inhibitory effect on tumor growth and metastasis. However, clinical translation of UA is limited by its poor water solubility and low bioavailability. To overcome these problems, herein an amphiphilic self-assembly nanodrug composed of UA, lactobionic acid (LA) and low-polyamidoamine (low-PAMAM) dendrimers is developed. This near-spherical nanodrug with a uniform size (~180 nm) demonstrated to have an enhanced cytotoxicity against liver cancer SMMC7721 cells, and could attenuate the migration and adhesion of SMMC7721 cells at non-toxic concentrations by suppressing metastasis-related protein MMP-9 expression. Furthermore, in vivo study indicates that the nanodrug exhibited prolonged circulation time in blood as well as increased AUC, MRT and Cmax, and could effectively inhibit the tumor growth in H22 mice model. Overall, the UA-based nanodrug delivery system reported in the present work represents a novel strategy for targeted tumor therapy.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Dendrímeros/química , Sistemas de Liberação de Medicamentos , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Nanopartículas/administração & dosagem , Triterpenos/química , Animais , Antineoplásicos/química , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dissacarídeos/química , Portadores de Fármacos , Neoplasias Hepáticas Experimentais/patologia , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Nanopartículas/química , Metástase Neoplásica , Ratos , Ratos Sprague-Dawley , Células Tumorais Cultivadas , Ácido Ursólico
19.
J Craniofac Surg ; 29(5): 1258-1260, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29521746

RESUMO

Cranioplasty (CP) is considered a low-risk operation in the field of neurosurgery following decompression craniectomy. Nevertheless, CP is still burdened by surgical complications, among which early or late infections are the most common outcome-threatening ones. Most of infection cases occur within a week after CP. Except that, implant-associated scalp infection is the most common complication, and leads to implant removal in many patients with refractory and recurrent infection. The authors reported a patient presenting with epidural infection about 3 months after titanium implant and cured by anti-infective treatment for 2 weeks.


Assuntos
Procedimentos de Cirurgia Plástica , Crânio/cirurgia , Infecção da Ferida Cirúrgica/tratamento farmacológico , Titânio/uso terapêutico , Anti-Infecciosos/uso terapêutico , Tratamento Conservador , Humanos , Procedimentos de Cirurgia Plástica/efeitos adversos , Procedimentos de Cirurgia Plástica/métodos
20.
Opt Express ; 25(4): 3083-3091, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28241525

RESUMO

The propagation dynamics of radially polarized (RP) pulses in a gas-filled hollow-core fiber (HCF) is numerically studied. It is found that the stable transverse mode of RP pulse in HCF is not TM01 mode, nor any eigenmodes in terms of Bessel functions. Compared with linearly polarized (LP) pulses, the RP pulses with the same initial pulse duration and energy have higher transmission efficiency, more uniform spectral broadening, and cleaner temporal profile after highly nonlinear propagation in HCF and better focusing properties. These results suggest that energetic few-cycle RP pulses can be generated more efficiently by directly spectral broadening the RP pulses in HCF followed by temporal compression.

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