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1.
Adv Mater ; 34(38): e2205563, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35918709

RESUMO

Due to the intrinsic lack of spatial order and self-supported shape, liquids are often incompatible with precision manufacturing/processing and are potentially limited for advanced functionality. Herein, an optothermal strategy is developed to fully command phase-separated liquids with unprecedented spatiotemporal addressability. Specifically, a laser is focused onto an Au film to create a hot spot that locally demixes a temperature-responsive solution to produce a single optothermal droplet. Spatial precision is assured by the well-defined thermal field and temporal accuracy guaranteed by the fast heating and response rate. Time-multiplexed laser foci are deployed to engineer the thermal landscape as desired, which in turn dictates the formation/dissolution, positioning, shaping, and dynamic reconfiguration of the phase-separated liquids. Further, laser foci are programmed to orchestrate the liquid patterns in a time-continuous manner to produce liquid animations on the microscale with high fidelity. While focused lasers are routinely used to manipulate solid particles or to microfabricate solid materials, the current strategy embraces the merits of liquids and features functional complexity in information encryption, payload transportation, and reaction localization. The strategy is further applicable in scenarios such as subcellular organization of biomolecular condensates and programmable modulation of non-equilibrium systems.


Assuntos
Lasers , Temperatura
2.
Soft Matter ; 18(26): 4881-4886, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35730484

RESUMO

Originated from supramolecular chemistry, the host-guest concept is generalized and appreciated across the fields of enzyme catalysis, biological channel conduction, and carbon nanotube transport, to name a few. Despite the extensive study of host-guest thermodynamics, it is still a fundamental challenge to directly measure its dynamics in real-space and real-time. Herein we approach such dynamics by direct imaging and tracking in a colloid-in-tube system, where self-assembled tubes are the hosts and sphere particles are the guests. The key difference from a previously reported static 1D confinement is that the present tubes are thermally actuated and capable of translations and rotations. It is the host tube thermal motions that impose a number of anomalies to guest particle dynamics including broadened distribution perpendicular to the tube, enhanced diffusion parallel to the tube phenomenologically resembling the rapid flow in ion channels or carbon nanotubes, and induced long-range particle-particle attraction analogous to capillary condensation. This work in the colloidal system is of wide implications for host-guest systems that are naturally embedded in thermal fluctuations such as transmembrane ion channels and carbon nanotube arrays in a soft matrix.

3.
Carbohydr Polym ; 137: 701-708, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26686182

RESUMO

A novel polysaccharide-peptide complex CNP-1-2 with molecular weight of 9.17 × 10(4) Da was obtained from Clinacanthus nutans Lindau leaves by hot water extraction, ethanol precipitation, and purification with Superdex 200 and DEAE-Sepharose Fast Flow column chromatography. CNP-1-2 exhibited the highest growth inhibitory effect on human gastric cancer cells SGC-7901 with inhibition ratio of 92.34% and stimulated activation of macrophages with NO secretion level of 47.53 µmol/L among the polysaccharide fractions. CNP-1-2 comprised approximately 87.25% carbohydrate and 9.37% protein. Monosaccharide analysis suggested that CNP-1-2 was composed of L-rhamnose, l-arabinose, D-mannose, D-glucose and D-galactose with a molar ratio of 1.30:1.00:2.56:4.95:5.09. Methylation analysis, FT-IR, and (1)H NMR spectroscopy analysis revealed that CNP-1-2 might have a backbone consisting of 1,4-linked Glcp, 1,3-linked Glcp, 1,3-linked Manp, 1,4-linked Galp, 1,2,6-linked Galp and 1,2,6-linked Galp. Its side chain might be composed of 1-linked Araf, 1,6-linked Galp and 1-linked Rhap residues. AFM (atomic force micrograph) analysis revealed that CNP-1-2 had the molecular aggregation along with branched and entangled structure.


Assuntos
Acanthaceae/química , Folhas de Planta/química , Polissacarídeos/química , Proteoglicanas/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular , Humanos , Espectroscopia de Ressonância Magnética , Peso Molecular , Polissacarídeos/farmacologia , Proteoglicanas/química , Proteoglicanas/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico
4.
Molecules ; 20(9): 17405-28, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26393569

RESUMO

Clinacanthans nutans (Burm. f.) Lindau is a popular medicinal vegetable in Southern Asia, and its extracts have displayed significant anti-proliferative effects on cancer cells in vitro. However, the underlying mechanism for this effect has yet to be established. This study investigated the antitumor and immunomodulatory activity of C. nutans (Burm. f.) Lindau 30% ethanol extract (CN30) in vivo. CN30 was prepared and its main components were identified using high-performance liquid chromatography (HPLC) and mass spectrometry (LC/MS/MS). CN30 had a significant inhibitory effect on tumor volume and weight. Hematoxylin and eosin (H & E) staining and TUNEL assay revealed that hepatoma cells underwent significant apoptosis with CN30 treatment, while expression levels of proliferation markers PCNA and p-AKT were significantly decreased when treated with low or high doses of CN30 treatment. Western blot analysis of PAPR, caspase-3, BAX, and Bcl2 also showed that CN30 induced apoptosis in hepatoma cells. Furthermore, intracellular staining analysis showed that CN30 treatment increased the number of IFN-γ⁺ T cells and decreased the number of IL-4⁺ T cells. Serum IFN-γ and interleukin-2 levels also significantly improved. Our findings indicated that CN30 demonstrated antitumor properties by up-regulating the immune response, and warrants further evaluation as a potential therapeutic agent for the treatment and prevention of cancers.


Assuntos
Acanthaceae/química , Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Hepatite A/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Extratos Vegetais/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/virologia , Cromatografia Líquida , Etanol/química , Etanol/isolamento & purificação , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hepatite A/imunologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/virologia , Camundongos , Estrutura Molecular , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Espectrometria de Massas em Tandem , Ensaios Antitumorais Modelo de Xenoenxerto
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