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1.
ACS Nano ; 16(3): 3554-3562, 2022 Mar 22.
Article in English | MEDLINE | ID: mdl-35231174

ABSTRACT

Interfacial solar steam generation (ISSG) utilizing local heating technology for evaporation at the water-to-steam interface is drawing great attention because of its high efficiency of solar-thermal conversion for a sustainable and eco-friendly drinking water regeneration process. Here, inspired by the structure of penguin feathers and polar bear hairs that both have macropores to trap air for thermal insulation, we report a bionic solar evaporator (BSE) with macroporous skeleton for partial thermal management and macro patulous channels for abundant water transportation and rapid steam extraction. Meanwhile, the 3D hierarchical isotropic truss structures can induce multiple light reflections to enable omnidirectional light absorption, and bimodal pores facilitate ion diffusion to suppress salt deposits. This BSE exhibits an evaporation rate of 2.3 kg m-2 h-1 and efficiency of 93% under 1 sun. The multiple advantages of high efficiency and salt resistance make BSE available for future practical sewage purification and desalination applications.

2.
Article in English | MEDLINE | ID: mdl-33995546

ABSTRACT

Melanoma is a serious malignant form of skin cancer. Euphorbiaceae compound B (ECB, 2,4-dihydroxy-6-methoxy-3-methylacetophenone) is an acetophenone compound that is isolated from Euphorbia ebracteolata Hayata (EEH), an herbaceous perennial, and has antitumor activity. Here, we transplanted human melanoma cells into zebrafish embryos to establish a zebrafish/melanoma model. We showed that this model can be used to evaluate the therapeutic effect of EEH and ECB and discussed its potential mechanism of action. The results showed that ECB was an active ingredient of EEH in inhibiting melanoma-induced hyperplasia of blood vessels in zebrafish embryos, similar to the angiogenic inhibitor vatalanib. ECB inhibited the number and length of subintestinal veins (p < 0.05), as well as the distribution of melanoma in zebrafish embryos (p < 0.05). More importantly, unlike vatalanib, ECB only inhibited melanoma-induced abnormal and excessive growth of blood vessels in xenografts. In addition, ECB inhibited the mRNA expression of vegfr2 and vegfr3 in zebrafish. Both vegfr2 and vegfr3 are essential genes that regulate blood vessel formation and upregulate the expression of p53 and casp3a genes in zebrafish. Together, the above-mentioned results indicate that ECB has a potential antimelanoma effect in vivo, which may be mediated by inhibiting vascular endothelial growth factor receptors.

3.
J Appl Toxicol ; 41(3): 483-492, 2021 03.
Article in English | MEDLINE | ID: mdl-33085127

ABSTRACT

Medicinal plants of the genus Aconitum are one of the most commonly used herbs in traditional medicine in East Asia to treat conditions related to the heart, pain, or inflammation. However, these herbs are also dangerous as accidental poisoning due to misuse is a recurring issue. These plants contain a number of diester-diterpenoid alkaloid compounds and aconitine is the most abundant and active one. This study investigated neurotoxicity of aconitine to zebrafish embryos in early development in relation to serotonin regulation. Experimental results showed that aconitine exposure (1, 10, and 100 µM) increased frequency of coiling behavior in zebrafish embryos in a dose-dependent manner and this effect can be triggered by either exposure to 5-hydroxytryptamine 1A (5-HT1A) receptor agonist (±)-8-hydroxy-2-(dipropylamino)tetralin (8-OH-DPAT) or overexpression of serotonin receptor 5-htr1ab. At the same time, coiling behavior caused by aconitine exposure could be rescued by co-exposure to 5-HT1A receptor antagonist WAY-100635 Maleate (WAY100635) and knockdown of 5-htr1ab using morpholino. Exposure to aconitine also significantly increased serotonin receptor 5-htr1ab and 5-htr1bd gene expression at 24 h post fertilization (hpf), but decreased their expression and protein expression of the serotonin receptor at 96 hpf with the high dose. These results suggest that neurotoxicity caused by aconitine is mediated through the 5-HT receptor.


Subject(s)
Aconitine/toxicity , Embryo, Nonmammalian/drug effects , Embryonic Development/drug effects , Plants, Medicinal/toxicity , Receptors, Serotonin/drug effects , Synaptic Transmission/drug effects , Zebrafish/growth & development , Aconitum/chemistry , Animals
4.
Polymers (Basel) ; 12(10)2020 Oct 18.
Article in English | MEDLINE | ID: mdl-33081063

ABSTRACT

There has been a growing interest in polymer applied for soil reinforcement in recent years. However, there little attention has been paid to the effects of polymer on soil cracking behavior, and cracks significantly change soil strength and hydraulic properties and alter reinforcement effectiveness. This study investigated the desiccation cracking behavior of polyurethane (PU) and polyacrylamide (PAM) admixed clayey soils with different polymer concentrations by performing desiccation cracking tests. Scanning electron microscope (SEM) observation was also carried out to obtain the internal structure of these soils. The results show that PU and PAM addition both prolonged the initial evaporation stage, accelerated later evaporation processes, and the effects were related to polymer concentration. Final cracks morphology analyses show that PAM addition slightly reduced the cracking and crushing degree and kept the soil relatively intact, while PU addition slightly enhanced the cracking and crushing degree of soil. In addition, PU and PAM addition both increased the width and length of cracks. The scanning electron microscopy (SEM) analyses show that the effects of polymer on soil evaporation and cracking could be concluded as: (1) storing water in voids, (2) influencing water immigration channel, (3) providing space for soil shrinkage, and (4) enhancing the connection between aggregates, which did not fully come into play because of the existence of hydrogel form. These achievements provide a certain basis for the research of desiccation cracking behavior of polymer treated soil and make significant sense for the safe and effective running of related projects.

5.
Polymers (Basel) ; 11(10)2019 Sep 27.
Article in English | MEDLINE | ID: mdl-31569683

ABSTRACT

As renewable and environment-friendly materials, coir and sisal natural fibers can be used in soil reinforcement with minimum cost and other benefits. In this study, we focused on their improvements of unconfined compressive properties of polymer treated sand. In total, 36 groups of unconfined compressive strength tests, combined with X-ray diffraction and scanning electron microscope investigations were performed. We had studied the effects of polymer and fiber contents, and fiber types on the reinforcement effectiveness. The results showed that both coir and sisal fiber can improve the mechanical properties and microstructure of treated sand. In terms of strength properties, sisal fiber inclusion was better than coir fiber, while both have a similar reinforcement benefit on soil ductile behaviors. The strength and compressive energy increased with an increment in polymer and fiber content. The reinforced sand can have up to 1 MPa compressive strength and 140 kPa compressive energy for coir fiber inclusion, while 1.2 MPa and 170 kPa, respectively, for sisal fiber. The axial stress-strain characteristics and failure patterns were also improved, and the brittle index decreased toward zero, which suggests an increasing ductile. The polymer membrane enwrapping and bonding sand grains, and the network structure built by fiber crossing and overlapping among sand grains, as well as the interfacial attachment conferred by polymer between sand grains and fiber, all contributed to the reinforcement of treated sand.

6.
Polymers (Basel) ; 11(3)2019 Mar 17.
Article in English | MEDLINE | ID: mdl-30960490

ABSTRACT

The significant criterion for evaluating the merits of a new type of high molecular polymer lies in its engineering properties and eco-friendliness. The focus of this study was to determine the effects of preparation conditions on the viscosity of the polyvinyl acetate (PVAc) emulsion, including reaction temperature (Tr), initiator concentration (CAPS), monomer concentration (CVA), pH value, and degree of dilution (Ddi). Based on the results of a series of laboratory tests, the range of viscosity value of PVAc was obtained under different conditions, and one set of viscosity values out of these was applied to soil reinforcement tests. Meanwhile, based on the test results, the engineering properties of PVAc solution were evaluated using strength and moisture retention tests, and the reinforcement mechanism was analyzed using scanning electron microscopy (SEM). In addition, it was proven through a vegetation growth test that the PVAc was eco-friendly.

7.
Zhongguo Zhong Yao Za Zhi ; 43(19): 3962-3969, 2018 Oct.
Article in Chinese | MEDLINE | ID: mdl-30453724

ABSTRACT

To establish the high performance liquid chromatography (HPLC) fingerprint for Digeda-4 decoction (DGD-4D), determine the contents of aesculetin, geniposide, picroside Ⅰ, picroside Ⅱ and ellagicacid in DGD-4D, and provide the scientific foundation for quality control of DGD-4D. The analysis was performed on Diamonsil(2) C18 (4.6 mm×250 mm,5 µm) column, with methanol-0.1% phosphoric acid aqueous solution as mobile phase for gradient elution. The flow rate was 1.0 mL·min⁻¹; injection size was 10 µL; temperature was maintained at 30 °C, and the detection wavelength was set at 254 nm. The common mode of DGD-4D HPLC fingerprint was established, and the hidden information was analyzed by Chemometrics. Chromatographic peaks for DGD-4D were identified by HPLC and quantitative analysis was conducted for characteristic peaks. There were 17 common peaks in the fingerprints and the similarity of the fingerprints was over 0.9 in all 15 batches. The samples were broadly divided into four kinds by principal component analysis and clustering analysis. Four marker compounds were verified by partial least squares discriminant analysis, and No. 9, 12 and 14 peaks were identified as geniposide, picroside Ⅱ, and picroside Ⅰ respectively. The average recoveries were in the range of 95.91%-97.31%. The HPLC fingerprint method for content determination is reliable, accurate, rapid, simple, and reproducible, and can be used as one of the effective methods to control the quality of DGD-4D.


Subject(s)
Drugs, Chinese Herbal/analysis , Drugs, Chinese Herbal/standards , Chromatography, High Pressure Liquid , Cinnamates , Iridoid Glucosides , Iridoids , Methanol , Principal Component Analysis , Quality Control
8.
Chem Biodivers ; 15(10): e1800215, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30027551

ABSTRACT

A cobalt(III) complex, [Co(L)2 ](ClO4 )3 (1), in which the ligand L was N,N-diethyl-4-(2,2':6',2''-terpyridin-4'-yl)aniline (L), was synthesized and fully characterized. This new cobalt(III) complex 1 exhibited selective cytotoxicity against HeLa, T-24, A549, MGC80-3, HepG2, and SK-OV-3 cells with IC50 values in the micromolar range (0.52 - 4.33 µm), and it exhibited low cytotoxicity against normal HL-7702 cells. The complex 1 was the most potent against the T-24 cells. It was found that 1 could cause the cell cycle arrest in G1 phase, and it exerted its antitumor activity mainly via disruption of mitochondrial function.


Subject(s)
Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cobalt/chemistry , Cobalt/pharmacology , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Aniline Compounds/chemical synthesis , Aniline Compounds/chemistry , Aniline Compounds/pharmacology , Antineoplastic Agents/chemical synthesis , Apoptosis/drug effects , Cell Line, Tumor , Coordination Complexes/chemical synthesis , Drug Screening Assays, Antitumor , G1 Phase Cell Cycle Checkpoints/drug effects , Humans , Membrane Potentials/drug effects , Mitochondria/drug effects , Mitochondria/metabolism , Mitochondria/pathology , Models, Molecular , Neoplasms/drug therapy , Neoplasms/metabolism , Neoplasms/pathology
9.
Polymers (Basel) ; 10(3)2018 Mar 08.
Article in English | MEDLINE | ID: mdl-30966322

ABSTRACT

Due to weak physical properties of sand, chemical reinforcement methods are widely used to improve sand properties to meet the engineering requirements. However, most of the traditional additives cause environmental problems. Therefore, non-traditional additives such as liquid polymers, enzymes, ions, and lignin derivatives have been studied extensively. In this study, organic polymer is used as a soil stabilizer to reinforce the sand. To evaluate the effectiveness of the organic polymer as soil stabilizer, a series of unconfined compression strength (UCS) tests, direct shear tests, and tensile tests were carried out on reinforced sand with different polymer concentrations and dry densities of sand. The reinforcement mechanism was analysed with scanning electron microscopy (SEM) images. The results indicated that the polymer concentration and dry density of sand had significant effects on the strength characteristics of reinforced sand specimens. The unconfined compressive strength, cohesion, and tensile strength of specimens with the same dry density increased with the increasing polymer concentration. The polymer membranes-formed by the mixture of polymer and water-enwrap the sand particles and interlink them to form a stable structure. The efficiency of this stabilization changed with dry sand density.

10.
Polymers (Basel) ; 10(5)2018 May 04.
Article in English | MEDLINE | ID: mdl-30966533

ABSTRACT

Physical and chemical reinforcements are commonly used to improve sand properties for engineering requirements. Many researchers have concluded that composite reinforcement can greatly improve sand property strength. In this paper, polyurethane organic polymer (PU) and polypropylene fiber (PF) were used to reinforce sand. It is found that composite reinforcement has great effects on tensile strength. A series of direct tensile tests were conducted to demonstrate this reinforcement and to investigate the effects of PF content, PU content, dry density, and curing time. Additionally, the reinforcement mechanism was analyzed by scanning electron microscope images. The tensile strength increases with curing time until it reaches a plateau. The composite reinforcement improves the tensile strength exponentially with the increase of PF and PU contents. For the effect due to dry density, the tensile strength first increased and then decreased with the peak at approximately 1.55 g/cm³. Through the interaction force among fibers and sand particles and the bonding force of polymer among sand particles, tensile strength of reinforced sand is greatly improved.

11.
Polymers (Basel) ; 10(8)2018 Aug 18.
Article in English | MEDLINE | ID: mdl-30960849

ABSTRACT

Sand mixed with geotextile/fiber/cement/lime or non-traditional chemical additives to form composite materials is recognized as an effective method for improving the sand properties. In this work, the variation in properties of composite materials after immersion is reported which has rarely appeared in the literature. The focus of this study is to evaluate the shear behaviors of polymer-sand composite material after immersion with direct shear tests. Several factors which may influence the shear behaviors after immersion are analyzed. The results demonstrate that this composite material still has good shear behaviors after immersion when compared to the purely sand material. The shear behaviors are improved with an increment in the curing time, polymer content and sand dry density while there is a decrease in the shear behaviors with increasing immersion time. The interaction between sand particles and the polymer are analyzed with Scanning Electron Microscope (SEM). The polymer membranes are formed by polymer enwrapping and connected sand particles to build an elastic and viscous structure in the sand that increases the interlocking forces between sand particles and decreases the void ratio of this material. The membranes are softened in water resulting in a decrease in the shear strength. Moreover, other factors affect the shear behaviors by improving the completeness and stability of this structure.

12.
Medchemcomm ; 8(3): 633-639, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-30108780

ABSTRACT

A new iron(iii) complex with 5,7-dichloro-2-methyl-8-quinolinol (HClMQ) as ligands, i.e., [Fe(ClMQ)2Cl] (1), was synthesized and evaluated for its anticancer activity. Compared to the HClMQ ligand, complex 1 showed a higher cytotoxicity towards a series of tumor cell lines, including Hep-G2, BEL-7404, NCI-H460, A549, and T-24, with IC50 values in the range of 5.04-14.35 µM. Notably, the Hep-G2 cell line was the most sensitive to complex 1. Mechanistic studies indicated that complex 1 is a telomerase inhibitor targeting c-myc G-quadruplex DNA and can trigger cell apoptosis via inducing cell cycle arrest and DNA damage.

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