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1.
Nano Lett ; 22(3): 1039-1046, 2022 Feb 09.
Article in English | MEDLINE | ID: mdl-35048710

ABSTRACT

The interfacial properties within a composite structure of membranes play a vital role in the separation properties and application performances. Building an interlayer can facilitate the formation of a highly selective layer as well as improve the interfacial properties of the composite membrane. However, it is difficult for a nanomaterial-based interlayer to increase the flux and retention of nanofiltration membranes simultaneously. Here, we report a nanofiltration membrane with a hybrid dimensional titania interlayer that exhibits excellent separation performance. The interlayer, composed of Fe-doped titania nanosheets and titania nanoparticles, helps the formation of an ultrathin (∼30 nm thick) and defect-free polyamide selective layer with an ideal nanostructure. The hybrid dimensional interlayer endows the membrane with a superior permeability and alleviates flux decline. In addition, the rigid interlayer framework on a PVDF support drastically improves the pressure resistance of nanofiltration membranes and shows negligible flux loss up to 1.5 MPa of pressure.

2.
Curr Pharm Des ; 26(1): 138-159, 2020.
Article in English | MEDLINE | ID: mdl-31840598

ABSTRACT

Plants of the genus Vitex (Verbenaceae) are mainly distributed throughout tropical and temperate regions, and many Vitex plants have been traditionally used in folk medicine. Plants of this genus are a rich source of diterpenoids, which not only displayed versatile structural diversity with potential chemotaxonomical significance but also exhibited a wide range of biological activities, mainly including in vitro cytotoxic, antiinflammatory, antimicrobial, hormone level-regulating and antiangiogenic activities. Recently, a series of bioactive diterpenoids, with interesting carbon skeletons, have been reported and gathered considerable interest. This article systematically reviewed diterpenoids isolated from the genus Vitex that appeared in the literature up to December 2018, critically highlighting their structural diversity and pharmacological activities. Up to now, a total of 154 diterpenoids with diverse structures have been isolated and identified from Vitex plants. The authors also summarized the reported structure-activity relationships of those well explored Vitex diterpenoids. Finally, the authors discussed the challenges and potential applications of these diterpenoids in the future.


Subject(s)
Diterpenes , Phytochemicals/pharmacology , Vitex/chemistry , Diterpenes/chemistry , Diterpenes/pharmacology , Phytochemicals/chemistry , Structure-Activity Relationship
3.
Phytomedicine ; 58: 152825, 2019 May.
Article in English | MEDLINE | ID: mdl-30831463

ABSTRACT

BACKGROUND: The seeds of Vitex negundo, with rich lignans metabolites, have been widely used as a traditional Chinese medicine and Ayurvedic herbal medicine for the treatment of rheumatism and joint inflammation. The total lignans of Vitex negundo seeds (TOV) were suggested to play an important role in the treatment of arthritis. PURPOSE: The aim of the study was designed to investigate the anti-arthritic effects of TOV on collagen-induced arthritis (CIA) in rats as well as its possible mechanisms. METHODS: TOV was prepared by combined macroporous resin and polyamide column chromatography, and constituents of TOV were analyzed by HPLC. CIA model in rats was established by immunization with chicken type II collagen and then the rats were intragastrically administrated with TOV for 30 days. Rat arthritis was evaluated by measurements of hind paw edema, arthritis index score, weight growth and indices of thymus and spleen, and by histological examination. Levels of serum MMP-2, MMP-3, MMP-9, IL-1ß, IL-6, IL-8, IL-10, IL-17A and TNF-α were also examined. In addition, the expression of COX-2, iNOS and IκB, p-IκB in synovial tissues was evaluated by western blotting. The analgesic and anti-inflammatory effects of TOV were also evaluated in acetic acid-induced writhing and xylene-induced ear edema in mice, respectively. In addition, acute toxicity test was employed to preliminarily assess the safety of TOV. RESULTS: TOV significantly inhibited the paw edema and decreased the arthritis index, with no influence on the body weight and the indices of thymus and spleen of CIA rats. Meanwhile, TOV dose-dependently reduced the infiltration of inflammatory cells, synovial hyperplasia and attenuated cartilage damage. Additionally, the serum levels of IL-1ß, IL-6, IL-8, IL-17A, TNF-α, MMP-3 and MMP-9 were markedly decreased, while the level of serum IL-10 was increased in TOV-treated rats. The significant reduction of the expression of COX-2, iNOS and p-IκB and the notable increase of IκB in synovial tissues were also observed in TOV-treated animals. TOV also significantly inhibited acetic acid-induced writhing and decreased xylene-induced ear edema in mice. Finally, the maximal tolerable dose (MTD) of TOV was determined to be 16.0 g/kg. CONCLUSION: These results suggest that TOV has significant anti-arthritic effects on collagen-induced arthritis in rats, which may be attributed to the inhibition of the levels of IL-1ß, IL-6, IL-8, IL-17A, TNF-α, MMP-3 and MMP-9, and the increase of IL-10 in serum as well as down-regulation of the protein expression of COX-2 and iNOS in synovial tissues via suppressing the phosphorylation and degradation of IκB. Due to its high efficacy and safety, TOV can be regarded as a promising drug candidate for rheumatoid arthritis treatment.


Subject(s)
Arthritis, Experimental/drug therapy , Edema/drug therapy , Lignans/pharmacology , Medicine, Chinese Traditional , Vitex/chemistry , Animals , Arthritis, Experimental/chemically induced , Arthritis, Experimental/pathology , Chickens , Collagen Type II/adverse effects , Cyclooxygenase 2/metabolism , Cytokines/blood , Edema/pathology , Female , Male , Matrix Metalloproteinase 3/metabolism , Matrix Metalloproteinase 9/metabolism , Mice , Mice, Inbred ICR , Nitric Oxide Synthase Type II/metabolism , Rats , Rats, Sprague-Dawley , Seeds/chemistry , Synovial Membrane/drug effects , Synovial Membrane/pathology
4.
Int J Biol Macromol ; 122: 882-892, 2019 Feb 01.
Article in English | MEDLINE | ID: mdl-30408452

ABSTRACT

Anoectochilus roxburghii, a famous Chinese herbal medicine, has been commonly used for the treatment of liver disease, diabetes, and rheumatoid arthritis. Our study aimed to investigate the anti-rheumatoid arthritis effects of A. roxburghii polysaccharides (ARP), using the rat's model of type II collagen-induced arthritis (CIA). ARP was prepared by alcohol sedimentation and structurally characterized based on combined chemical, chromatographic and spectroscopic methods. High Performance Size Exclusion Chromatography-Multiangle Laser Light Scattering-Refrative Index (HPSEC-MALLS-RI) analysis revealed that ARP includes two peaks, and the weight-average molecular weight (Mw) of the principal one was estimated as 5.90 kDa with a relative content of 98.2%. Pharmacological results exhibited that ARP significantly decreased the arthritis index and ameliorated the inflammatory cell infiltration and the synovial tissue destruction in CIA rats. Additionally, ARP possessed significant NO production inhibitory effects and antioxidant activity. Further anti-inflammatory mechanism investigations indicated that ARP significantly inhibited the activation of nuclear factor κB (NF-κB) pathway by suppressing the phosphorylation of IκB and p65, which subsequently down-regulated the mRNA expressions of IL-1ß and IL-6 in LPS-stimulated RAW 264.7 cells. These findings suggested that ARP has great potential in the development of functional foods and dietary supplements for the treatment of rheumatoid arthritis.


Subject(s)
Antioxidants/pharmacology , Arthritis, Experimental/chemically induced , Arthritis, Experimental/drug therapy , Collagen Type II/pharmacology , Orchidaceae/chemistry , Polysaccharides/pharmacology , Animals , Antioxidants/chemistry , Antioxidants/therapeutic use , Arthritis, Experimental/blood , Arthritis, Experimental/pathology , Interleukin-10/blood , Interleukin-1beta/blood , Interleukin-6/blood , Male , Molecular Weight , Monosaccharides/analysis , Polysaccharides/chemistry , Polysaccharides/therapeutic use , Rats , Rats, Wistar , Tumor Necrosis Factor-alpha/blood
5.
Materials (Basel) ; 11(8)2018 Aug 13.
Article in English | MEDLINE | ID: mdl-30104493

ABSTRACT

Mixed matrix membranes (MMMs) attract great attention due to their outstanding gas separation performance. The compatibility between the fillers and the polymer matrix is one of the key points for the preparation of high-performance MMMs. In this work, MMMs consisting of metal-organic frameworks (MOFs) of amine-modified Cu-BTC (NH2-Cu-BTC; BTC = 1,3,5-benzenetricarboxylic acid) and submicrometer-sized amine-modified Cu-BTC (sub-NH2-Cu-BTC) incorporated into a Pebax-1657 polymer were fabricated for the gas separation. The SEM image and Fourier transform infrared spectroscopy (FTIR) spectra showed an increase in the surface roughness of MOFs and the presence of amino groups on the surface of Cu-BTC after the amination modification, and a decrease in the size of MOFs crystals after the submicrometer-sized aminated modification. Gas adsorption analysis indicated that NH2-Cu-BTC and sub-NH2-Cu-BTC had a higher gas adsorption capacity for CO2 compared to the unmodified Cu-BTC. The scanning electron microscopy (SEM) image showed that NH2-Cu-BTC and sub-NH2-Cu-BTC, especially sub-NH2-Cu-BTC, had a better compatibility with a polyether-block-amide (Pebax) matrix in the MMMs. The gas separation performance indicated that the Pebax/sub-NH2-Cu-BTC MMMs evidently improved the CO2/N2 and CO2/CH4 selectivity at the expense of a slight CO2 permeability. The results reveal that modified MOF-filled MMMs possess great potential for applications in the CO2 separation field.

6.
Fitoterapia ; 127: 362-366, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29626624

ABSTRACT

Chemical investigation on the solid rice culture of Trichoderma atroviride S361, an endophyte isolated from Cephalotaxus fortunei, has afforded a pair of novel N-furanone amide enantiomers, (-)-trichodermadione A (1a) and (+)-trichodermadione A (1b), and a new cyclohexenone sesquiterpenoid, trichodermadione B (2), together with six known secondary metabolites. Chiral separation of compound 1 was successfully performed on a Lux Cellulose-2 column. Their structures were elucidated by detailed spectroscopic analyses on the basis of NMR, HRMS, and ECD data, and the absolute configurations of the new compounds were determined by computational analyses of their electronic circular dichroism (ECD) spectra and Snatzke's method. Compounds 1a, 1b and 2 were also evaluated for their cytotoxicity against DU145 and PC3 cell lines, as well as inhibitory effects against the production of NO in LPS-stimulated RAW264.7 cells.


Subject(s)
Cephalotaxus/microbiology , Trichoderma/chemistry , Animals , Cell Line, Tumor , Endophytes/chemistry , Humans , Mice , Molecular Structure , RAW 264.7 Cells
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