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1.
Int J Biol Macromol ; 268(Pt 2): 131684, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38663695

RESUMO

Cracking, warping, and decaying stemming from wood's poor dimensional stability and durability are the most annoying issues of natural wood. There is an urgent need to address these issues, of which, sustainable and green chemical treatments are favorably welcomed. Herein, we developed a facile method through the incorporation of environmentally friendly biopolymer lignin into wood cells for wood dimensional stability and durability enhancement. Enzymatic hydrolysis lignin (EHL) was dissolved into various solvents followed by impregnation and drying to incorporate lignin into wood cells. Impregnation treatment was developed to incorporate into wood to improve its dimensional stability, durability, and micromechanics. The anti-swelling efficiency reached up to 99.4 %, the moisture absorption decreased down to 0.55 %, the mass loss after brown rot decay decreased to 7.22 %, and the cell wall elasticity as well as hardness increased 8.7 % and 10.3 %, respectively. Analyses acquired from scanning electron microscopy, fluorescent microscopy, and Raman imaging revealed that the EHL was successfully colonized in cell lumen as well as in cell walls, thus improved wood dimensional stability and durability. Moreover, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy confirmed EHL interaction with the cell wall components, thus the wood mechanical property was not impaired significantly, whereas nanoindentation data indicated even slight mechanical enhancement on the cell walls. This facile approach can improve the wood properties in multiple aspects and remarkably enhance the outdoor performance of modified wood products. In addition, using lignin as a natural modifying agent to improve wood performance will have a great positive impact on the environment.


Assuntos
Lignina , Madeira , Lignina/química , Madeira/química , Parede Celular/química , Hidrólise , Espectroscopia de Infravermelho com Transformada de Fourier
2.
J Colloid Interface Sci ; 668: 272-281, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38678883

RESUMO

HYPOTHESIS: Microcapsules with osmotically-inflated elastic shells exhibit an ultrafast release of encapsulants while mechanically stimulating the microenvironments, akin to popping balloons. EXPERIMENTS: To prepare elastic shells with uniform thickness and size, monodisperse water-in-oil-in-water (W/O/W) double-emulsion drops are produced in a capillary microfluidic device. The polydimethylsiloxane (PDMS)-containing oil phase is thermally cured to create the elastic shell. The elastic shells are inflated by pumping water into the lumen in hypotonic conditions. The inflated microcapsules produced undergo mechanical compression, and their release properties are studied. FINDINGS: By controlling the osmotic pressure difference, Microballoons are inflated into a diameter of 200 µm - 316 µm and shell thickness of 7.8 µm - 0.7 µm, respectively. The inflated shell pops due to mechanical failure when subjected to mechanical stress above a certain threshold, resembling a balloon. During popping, the stretched shell rapidly retracts to the original uninflated state, resulting in an ultrafast release of encapsulants from the lumen within a millisecond. This process converts elastic potential energy stored in the shell into mechanical energy with substantial power. The microballoons mechanically stimulate the local environment, leading to the direct and rapid release of encapsulants. This has the potential to improve absorption efficiency.

3.
J Cosmet Dermatol ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38501159

RESUMO

BACKGROUND: AGEs accumulate in the skin as a result of a high-sugar diet and play an important role in the skin aging process. OBJECTIVES: The aim of this study was to characterize the mechanism underlying the effect of a high-sugar diet on skin aging damage at a holistic level. METHODS: We established a high-sugar diet mouse model to compare and analyze differences in physiological indexes. The effect of a high-sugar diet on skin aging damage was analyzed by means of a transcriptome study and staining of pathological sections. Furthermore, the differences in the protein expression of AGEs and ECM components between the HSD and control groups were further verified by immunohistochemistry. RESULTS: The skin in the HSD group mice tended toward a red, yellow, dark, and deep color. In addition, the epidermis was irregular with anomalous phenomena, the epidermis was thinned, and the dermis lost its normal structure and showed vacuolated changes. Transcriptomics results revealed significant downregulation of the ECM-receptor interaction pathway, significant upregulation of the expression of AGEs and significant downregulation of the expression levels of COLI, FN1, LM5, and TNC, among others ECM proteins and ECM receptors. CONCLUSIONS: High-sugar diets cause skin aging damage by inducing the accumulation of AGEs, disrupting the expression of ECM proteins and their receptors, and downregulating the ECM-receptor interaction pathway, which affects cellular behavioral functions such as cell proliferation, migration, and adhesion, as well as normal skin tissue structure.

4.
Int Immunopharmacol ; 119: 110213, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37137266

RESUMO

P-Hydroxylcinnamaldehyde (CMSP) was firstly isolated from Chinese medicine Cochinchinnamomordica seed (CMS) by our team and has been verified to have growth-inhibiting abilities in malignant tumors including esophageal squamous cell carcinoma (ESCC). However, the detailed mechanism of its function is still unclear. Tumor-associated macrophages (TAMs) are an essential component of the tumor microenvironment (TME), playing important roles in tumor growth, metastasis, angiogenesis, and epithelial-mesenchymal transition (EMT). In the present study, we found that the percentage of M1-like macrophages was significantly increased in TME of ESCC cell derivedxenograft tumor model after CMSP treatment, while the ratios of other immune cells showed relatively low variation. To confirm these results, we further examined the effect of CMSP on macrophage polarization in vitro. The results revealed that CMSP also could induce phorbol-12-myristate-13-acetate (PMA)-induced M0 macrophages from THP-1 and mouse peritoneal macrophages toward the M1-like macrophages. Furthermore, CMSP could exert anti-tumor effect through TAMs in vitro co-culture model, in addition, the growth inhibition effect of CMSP was partly abolished in macrophage depletion model. To determine the potential pathway of CMSP induced polarization, we used quantitative proteomics (label-free) technology to explore the proteomic changes under CMSP treatment. The results revealed that immune-activating protein and M1 macrophage biomarkers were significantly increased after CMSP treatment. More importantly, CMSP stimulated pathways related to M1 macrophage polarization, such as the NF-κB signaling pathway and Toll-like receptor pathway, indicating that CMSP might induce M1-type macrophage polarization through these pathways. In conclusion, CMSP can regulate immune microenvironment in vivo and induce TAM polarization toward the M1 type by promoting proteomic changes, and exert anti-tumor effect through TAMs.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Animais , Camundongos , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Proteoma , Neoplasias Esofágicas/tratamento farmacológico , Macrófagos Associados a Tumor/metabolismo , Proteômica , Microambiente Tumoral , Linhagem Celular Tumoral
5.
ACS Appl Mater Interfaces ; 14(16): 18159-18169, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35426298

RESUMO

There is a demand for submillimeter-sized capsules with an ultrathin shell with high visibility and no tactile sensation after release for cosmetic applications. However, neither bulk emulsification nor droplet microfluidics can directly produce such capsules in a controlled manner. Herein, we report the microfluidic production of submillimeter-sized capsules with a spacious lumen and ultrathin biodegradable shell through osmotic inflation of water-in-oil-in-water (W/O/W) double-emulsion drops. Monodisperse double-emulsion drops are produced with a capillary microfluidic device to have an organic solution of poly(lactic-co-glycolic acid) (PLGA) in the middle oil layer. Hypotonic conditions inflate the drops, leading to core volume expansion and oil-layer thickness reduction. Afterward, the oil layer is consolidated to the PLGA shell through solvent evaporation. The degree of inflation is controllable with the osmotic pressure. With a strong hypotonic condition, the capsule radius increases up to 330 µm and the shell thickness decreases to 1 µm so that the ratio of the thickness to radius is as small as 0.006. The large capsules with an ultrathin shell readily release their encapsulant under an external force by shell rupture. In the mechanical test of single capsules, the threshold strain for shell rupture is reduced from 75 to 12%, and the threshold stress is decreased by two orders for highly inflated capsules in comparison with noninflated ones. During the shell rupture, the tactile sensation of capsules gradually disappears as the capsules lose volume and the residual shells are ultrathin.


Assuntos
Cosméticos , Microfluídica , Cápsulas , Emulsões , Osmose , Água
6.
RSC Adv ; 9(34): 19441-19449, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-35519395

RESUMO

A rapid, simple and cost-effective approach to prepare hierarchical porous carbons (PCs) for supercapacitors is reported by microwave activation of abundant and low-cost waste palm, biochar (BC) and KOH. BCs from waste palm at different carbonization temperatures (300-700 °C), as catalysts and microwave receptors, were used here for the first time to facilitate the conversion of waste palm into hierarchical PCs. As a result, the high-graphitization PC obtained at a BC carbonization temperature of 300 °C (PC-300) possessed a high surface area (1755 m2 g-1), a high pore volume (0.942 cm3 g-1) and a moderate mesoporosity (37.79%). Besides their high-graphitization and hierarchical porous structure, the oxygen doping in PC-300 can also promote the rapid transport of electrolyte ions. The symmetric supercapacitor based on the PC-300 even in PVA/LiCl gel electrolyte exhibited a high specific capacitance of 164.8 F g-1 at a current density of 0.5 A g-1 and retained a specific capacitance of 121.3 F g-1 at 10 A g-1, demonstrating a superior rate capacity of 73.6%. Additionally, the PC-300 supercapacitor delivered a high energy density of 14.6 W h kg-1 at a power density of 398.9 W kg-1 and maintained an energy density of 10.8 W h kg-1 at a high power density of 8016.5 W kg-1, as well as an excellent cycling stability after 2000 cycles with a capacitance retention of 92.06%.

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