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1.
Small ; : e2400740, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693082

RESUMO

Integrating self-healing capabilities into printed stretchable electronic devices is important for improving performance and extending device life. However, achieving printed self-healing stretchable electronic devices with excellent device-level healing ability and stretchability while maintaining outstanding electrical performance remains challenging. Herein, a series of printed device-level self-healing stretchable electronic devices is achieved by depositing liquid metal/silver fractal dendrites/polystyrene-block-polyisoprene-block-polystyrene (LM/Ag FDs/SIS) conductive inks onto a self-healing thermoplastic polyurethane (TPU) film via screen printing method. Owing to the fluidic properties of the LM and the interfacial hydrogen bonding and disulfide bonds of TPU, the as-obtained stretchable electronic devices maintain good electronic properties under strain and exhibit device-level self-healing properties without external stimulation. Printed self-healing stretchable electrodes possess high electrical conductivity (1.6 × 105 S m-1), excellent electromechanical properties, and dynamic stability, with only a 2.5-fold increase in resistance at 200% strain, even after a complete cut and re-healing treatment. The printed self-healing capacitive stretchable strain sensor shows good linearity (R2 ≈0.9994) in a wide sensing range (0%-200%) and is successfully applied to bio-signal detection. Furthermore, the printed self-healing electronic smart label is designed and can be used for real-time environmental monitoring, which exhibits promising potential for practical application in food preservation packaging.

2.
Int J Mol Sci ; 22(23)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34884501

RESUMO

Protein tyrosine phosphatase 1B (PTP1B) is a critical negative modulator of insulin signaling and has attracted considerable attention in treating type 2 diabetes mellitus (T2DM). Low-molecular-weight polymannuronic acid phosphate (LPMP) was found to be a selective PTP1B inhibitor with an IC50 of 1.02 ± 0.17 µM. Cellular glucose consumption was significantly elevated in insulin-resistant HepG2 cells after LPMP treatment. LPMP could alleviate oxidative stress and endoplasmic reticulum stress, which are associated with the development of insulin resistance. Western blot and polymerase chain reaction (PCR) analysis demonstrated that LPMP could enhance insulin sensitivity through the PTP1B/IRS/Akt transduction pathway. Furthermore, animal study confirmed that LPMP could decrease blood glucose, alleviate insulin resistance, and exert hepatoprotective effects in diabetic mice. Taken together, LPMP can effectively inhibit insulin resistance and has high potential as an anti-diabetic drug candidate to be further developed.


Assuntos
Ácido Algínico/química , Inibidores Enzimáticos/farmacologia , Proteínas Substratos do Receptor de Insulina/metabolismo , Resistência à Insulina , Fosfatos/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Apoptose , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Proliferação de Células , Inibidores Enzimáticos/química , Humanos , Proteínas Substratos do Receptor de Insulina/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos , Proteínas Proto-Oncogênicas c-akt/genética , Células Tumorais Cultivadas
3.
Adv Mater ; 35(41): e2304420, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37358069

RESUMO

The utilization of printing techniques for the development of high-performance humidity sensors holds immense significance for various applications in the fields of the Internet of Things, agriculture, human healthcare, and storage environments. However, the long response time and low sensitivity of current printed humidity sensors limit their practical applications. Herein, a series of high-sensing-performance flexible resistive-type humidity sensors is fabricated by the screen-printing method, and hexagonal tungsten oxide (h-WO3 ) is employed as the humidity-sensing material due to its low cost, strong chemical adsorption ability, and excellent humidity-sensing ability. The as-prepared printed sensors exhibit high sensitivity, good repeatability, outstanding flexibility, low hysteresis, and fast response (1.5 s) in a wide relative humidity (RH) range (11-95% RH). Furthermore, the sensitivity of humidity sensors can be easily adjusted by altering the manufacturing parameters of the sensing layer and interdigital electrode to meet the diverse requirements of specific applications. The printed flexible humidity sensors possess immense potential in various applications, including wearable devices, non-contact measurements, and packaging opening state monitoring.

4.
Int J Biol Macromol ; 211: 249-258, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35568151

RESUMO

Maintaining a moist and sterile environment is conducive to accelerating wound healing. To develop a natural wound dressing with good water retention capacity and antibacterial activity, we prepared a novel natural multifunctional hydrogel for infected wound healing, which combines the advantages of Aloe polysaccharide (AP) and honey. AP was extracted from Aloe barbadensis, and its structure was characterized by fourier transform infra-red (FT-IR) spectoscopy and nuclear magnetic resonance (NMR) spectroscopy. AP is an acetylated mannan composed of (1 â†’ 4)ß-Manp, which is acetylated at C-2, C-3 and C-6 positions. AP/Honey@PVA hydrogel was prepared by cross-linking AP, honey, PVA with borax, which has good mechanical strength and excellent biocompatibility for blood cells, NIH-3T3 cells and L929 cells. The hydrogels showed significant inhibitory effect on Staphylococcus aureus, Escherichia coli and Candida albicans, as well as accelerated the healing of infected full-thickness wound. This study reveals the structure of AP and proves that AP and honey composite hydrogel has potential application prospect in the therapy of infected wounds.


Assuntos
Aloe , Mel , Infecção dos Ferimentos , Animais , Antibacterianos/farmacologia , Escherichia coli , Hidrogéis/farmacologia , Camundongos , Polissacarídeos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Cicatrização
5.
Int J Biol Macromol ; 216: 510-519, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35803409

RESUMO

The substituents and backbones are two main factors affecting immune activities of polysaccharides. In the present study, we firstly evaluated the immunostimulating effects of phosphorylated, sulfated, H-phosphonated and nitrated derivatives of low-molecular-weight polymannuronate (LPM) and polyguluronate (LPG) on splenocytes and peritoneal macrophages in vitro. The results showed that the phosphate group was the best substituent to enhance the immune activities, and LPG phosphate (LPGP) had much better activity than LPM phosphate (LPMP). Further studies showed that LPGP not only promoted the proliferation of mouse splenocytes in the presence of either LPS or Con A, but also acted as an excellent peritoneal macrophage activator to enhance the cell phagocytosis, energy metabolism, cytokines release and activities of intracellular enzymes. The studies in RAW264.7 cells revealed that LPGP activated the TBK1-IκBα-NF-κB and the TBK1-IRF3 pathway. Moreover, LPGP rescued the immune response in the Cyclophosphamide-treated mice in vivo. In conclusion, LPGP is a potential alginate-based biological response modifier (BRM).


Assuntos
Adjuvantes Imunológicos , Baço , Adjuvantes Imunológicos/metabolismo , Adjuvantes Imunológicos/farmacologia , Animais , Imunidade , Macrófagos , Camundongos , NF-kappa B/metabolismo , Fosfatos/farmacologia , Polissacarídeos Bacterianos/farmacologia
6.
Polymers (Basel) ; 14(4)2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35215682

RESUMO

The human gut microbiota plays a critical role in the metabolism of dietary carbohydrates. Previous studies have illustrated that marine algae oligosaccharides could be utilized and readily fermented by human gut microbiota. However, the human gut microbiota is classified into three different enterotypes, and how this may affect the fermentation processes of marine algae oligosaccharides has not been studied. Here, using in vitro fermentation and 16 S high-throughput sequencing techniques, we demonstrate that the human gut microbiota has an enterotype-specific effect on the fermentation outcomes of marine algae oligosaccharides. Notably, microbiota with a Bacteroides enterotype was more proficient at fermenting carrageenan oligosaccharides (KOS) as compared to that with a Prevotella enterotype and that with an Escherichia enterotype. Interestingly, the prebiotic effects of marine algae oligosaccharides were also found to be enterotype dependent. Altogether, our study demonstrates an enterotype-specific effect of human gut microbiota on the fermentation of marine algae oligosaccharides. However, due to the availability of the fecal samples, only one sample was used to represent each enterotype. Therefore, our research is a proof-of-concept study, and we anticipate that more detailed studies with larger sample sizes could be conducted to further explore the enterotype-specific prebiotic effects of marine oligosaccharides.

7.
Carbohydr Res ; 460: 8-13, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29476992

RESUMO

The sulfation pattern plays a crucial role in chondroitin sulfate (CS) biological activity, and preparation of CS with defined structure is essential for accurate pharmacological study. In this study, we focused on the preparation of regioselective 4-O/6-O-desulfated CS derived from porcine, employing a dimethyl sulfoxide-methanol (DMSO-MeOH) method and an N-methyl-N-(trimethylsilyl) -trifluoroacetamide (MTSTFA) method CS, respectively. Results showed that the sulfate at C4 position (4-O-S) of N-acetylgalactosamine (GalNAc) was selectively removed by the DMSO-MeOH method, and the sulfate at C6 position (6-O-S) of GalNAc was selectively removed by the MTSTFA method. Structures of desulfated CS were characterized by means of FT-IR, NMR and disaccharide composition analysis. The preparations of regioselective 4-O/6-O-desulfated CS are powerful for the study of structure-activity relationship of CS.


Assuntos
Sulfatos de Condroitina/química , Dissacarídeos/química , Acetamidas/química , Dimetil Sulfóxido/química , Fluoracetatos/química , Espectroscopia de Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Estereoisomerismo , Especificidade por Substrato
8.
Biomed Pharmacother ; 105: 677-682, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29906745

RESUMO

Emerging evidence reveal that long noncoding RNAs (lncRNAs) participates in the epigenetic regulation of pathophysiological process. However, the deepgoing role of lncRNAs on meningioma is still unclear. In present study, we investigate the roles of lncRNA LINC00460 in meningeoma tissue and uncover its molecular mechanism. Results revealed that LINC00460 expression level was significantly up-regulated in meningeoma tissues and malignant meningeoma cell lines (IOMM-Lee, CH157-MN). Mechanically, loss-of-function assays showed that LINC00460 knockdown significantly suppressed the proliferation ability, increased the apoptosis and decreased the proteins (MMP-2, MMP-9, ZEB1) expression. Bioinformatics tools predicted that miR-539 both targeted with the 3'-UTR of LINC00460 and MMP-9 mRNA, which was confirmed by luciferase reporter assay and western blot analysis. In summary, our study reveals that LINC00460 promotes MMP-9 expression through targeting miR-539, acting as an oncogenic RNA in the meningeoma malignancy and accelerating the proliferation and metastasis of meningeoma.


Assuntos
Apoptose/genética , Proliferação de Células/genética , Metaloproteinase 9 da Matriz/genética , Meningioma/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Linhagem Celular Tumoral , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Meningioma/patologia , Regulação para Cima
9.
Int J Biol Macromol ; 114: 26-34, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29550423

RESUMO

Cardiovascular disease (CVD) is the No. 1 cause of death worldwide. Hyperlipidemia is one of the major risk factors for CVD. Maintaining lipid homeostasis is an effective way to prevent CVD. We prepared propylene glycol guluronate sulfate (PGGS), a sulfated polysaccharide, and investigated its effect on lipid metabolism in HepG2 cells. We found that total cholesterol (TC) and triglycerides (TG) were significantly decreased in the cells after PGGS treatment. We have also shown that the AMPK signaling is activated after PGGS treatment as evidenced by changes in the expression of many AMPK downstream targets including SREBP-1c, SIRT-1, CPT1, PPARα, and FAS. Our results have demonstrated that PGGS is a potentially novel lipid-lowering agent for CVD prevention.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Colesterol/biossíntese , Metabolismo dos Lipídeos/efeitos dos fármacos , Ácido Palmítico/toxicidade , Propilenoglicol/farmacologia , Triglicerídeos/biossíntese , Células Hep G2 , Humanos
10.
Carbohydr Polym ; 155: 313-320, 2017 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-27702517

RESUMO

A series of low-molecular-weight polymannuronate (LPM) and polyguluronate (LPG) polyanionic derivatives, including LPM/LPG phosphate (LPMP/LPGP), LPM/LPG H-phosphonate (LPMHP/LPGHP) and LPM/LPG sulfate (LPMS/LPGS), were prepared as heparinoids by chemical modification of LPM and LPG. The structures and characteristics of LPM, LPG and their derivatives were elucidated based on high performance gel permeation chromatography (HPGPC), fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (NMR) and polyacrylamide gel electrophoresis (PAGE). In order to test the heparin-like activities of these derivatives and to reveal the activities affected by substituent groups and PM/PG polysaccharide backbones, the anticoagulant activities and FGF/FGFR1c signaling activation abilities were evaluated in vitro. The results showed that sulfate group was the best substituent group to improve the heparin-like activities of LPM/LPG compared with the other two anionic groups. The results also showed that sulfated derivative based on PG structure had better activities than that based on PM structure.

11.
Int J Biol Macromol ; 62: 281-6, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24060457

RESUMO

Three derivatives of polymannuronic acid (PM) were prepared by chemically polyanionic modification. PM was substituted with phosphate (OPO3(2-)), H-phosphonate (OPO2H(-)) and sulfate (OSO3(-)) groups with the degree of substitution (DS) of 0.41, 1.42 and 1.04, respectively. The structures of all PM derivatives were characterized by FT-IR, (31)P NMR and (13)C NMR spectroscopy. The weight average molecular weight (Mw) was determined by high performance gel permeation chromatography (HPGPC). The antioxidant activities of PM and its derivatives were evaluated in vitro. The results indicated that both phosphate and H-phosphonate groups improved the hydroxyl radical scavenging activity, while sulfate group enhanced the superoxide radical scavenging activity. However, all of the derivatives scavenged DPPH less effectively than PM. The mechanism for how the different anionic substituent groups influenced the antioxidant activities was discussed.


Assuntos
Sequestradores de Radicais Livres/química , Ácidos Hexurônicos/química , Organofosfonatos/química , Fosfatos/química , Sulfatos/química , Radicais Livres/química
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