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As a type of reactive oxygen species (ROS), hydroxyl radical (·OH) is closely associated with many kinds of diseases. The present study aimed to develo p a novel OH fluorescent probe based on coumarin, a new compound that has not been previously reported. This probe exhibited good linear range and selectivity for ·OHl, and is able to avoid interference from some metal ions and other kinds of ROS (H 2 O 2 , O 2 .- , 1 O 2 , and HClO). Meanwhile, this probe has been used to evaluate the ·OH-scavenging efficiency of different compounds, such as isopropyl alcohol, cytosine, uracil, Tempo, Glutathione (GSH), and dimethyl sulfoxide (DMSO). Therefore, the present study shows that this probe not only can effectively measure the level of ·OH, but also can assess the ·OH-scavenging efficiency of different compounds. Furthermore this current study suggested that following further optimization, this probe may be potentially applied in the diagnosis of oxidative stress in human body., (© 2019 John Wiley & Sons, Ltd.)

This study was designed to systematically elucidate the immunomodulation effect of glycosaminoglycan from Apostichopus japonicus (AHG) in cyclophosphamide (CY)-induced immunosuppression model and potential mechanism responsible for the activation of macrophages. The results showed that the treatment with AHG could increase natural killer (NK) cell cytotoxicity, carbon clearance and marker enzymes activities in CY-induced immunosuppression mice, indicating that the innate immunity experienced recovery to some extent. Moreover, CY-induced reductions in thymus and spleen indices, serum levels of cytokines, immunoglobulins and hemolysin, as well as the ratio of spleen lymphocyte subsets were recovered by AHG, suggesting that AHG could improve the adaptive immunity through cellular immunity and humoral immunity. Delightedly, it was found that AHG at 10 mg/kg body weight could restore the CY-induced immunosuppression in mice to normal level on both innate and adaptive immunity. Furthermore, AHG also promoted both the expression of NO, TNF-α, IL-6, IL-1β, IL-18 and MCP-1 protein and related mRNA in macrophages. It was revealed that AHG activated macrophages through the phosphorylation of mitogen-activated protein kinase (MAPK) and nuclear factor-B (NF-κB). In conclusion, AHG exerts remarkable immunomodulatory activities in both innate and adaptive immune system. These findings should have great value for further study on the immunopotentiating mechanisms of this biomacromolecule., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Aim: Sini decoction (SND) is a commonly used herbal formula showing lipid-lowering effects and is applied in traditional Chinese medicine (TCM) for the treatment of cardiovascular disease (CVD) and atherosclerosis (AS). However, the mechanisms behind its anti-atherosclerotic effects are still unknown, and will be investigated in this study., Methods: AS was induced in rabbits by high fat diet (HFD) and treated with solvent (HFD group), atorvastatin (Ator group), or SND (SND group) for 12 weeks. Healthy rabbits (Chow group) were used as control. Serum and liver homogenates were collected, and lipid profiles as well as serum ApoA-I and ApoB were examined. Histopathological changes and lipid deposition in the proximal aorta and liver were detected by Oil red O staining. Western blot was used to detect the expression of ABCA1, ApoA-I, ApoB, PPARγ, and LXRα in liver, peritoneal macrophages, peripheral mononuclear cells (PMC), and adipose tissues., Results: SND significantly attenuated the levels of total cholesterol (TC), triglyceride (TG), and low density lipoprotein cholesterol(LDL-C) in serum and liver. However, high density lipoprotein cholesterol (HDL-C) dramatically increased. SND treatment also decreased lipid deposition and improved the structure of the liver and aorta. Furthermore, SND enhanced the expression levels of ABCA1, PPARγ, and LXRα in liver, adipose tissues, PMC, and peritoneal macrophages. It also upregulated hepatic and serum ApoA-I expression and serum ApoA-I/ApoB ratio. CONCLUSIONS:SND treatment relieved AS, improved lipid profiles, and increased serum HDL-C level. The potential mechanism behind this might be the improvement of reverse cholesterol transport (RCT) involved with enhanced expression of ABCA1, ApoA-I, PPARγ, and LXRα., Competing Interests: Conflict of interest: Authors state no conflict of interest, (© 2018 Shicong Ju et al., published by De Gruyter.)

In this study, a new fucosylated chondroitin sulfate (HsG) with an average molecular weight of 69.1 kDa was isolated from sea cucumber Holothuria scabra. We investigated the structure of the HsG by adopting monosaccharide composition analysis, disaccharide composition analysis, IR, 1 H and 13 C NMR spectra and methylation analysis. According to methylation results of desulfated/carboxyl-reduced polysaccharides and the analysis of unsaturated disaccharides generated through the enzymolysis of the defucosed polysaccharides, it is shown that each branch is formed by one fucopyranosyl residue, wherein 55.7% of the fucopyranosyl residues are linked to the O-6 position of the N-acetylgalactosamine moiety, 21.2% of the fucopyranosyl residues are linked to the O-3 position of β-d-glucuronic acid, 13.0% of the fucopyranosyl residues are linked to the O-4 positions of the N-acetylgalactosamine moiety, and 10.1% of the fucopyranosyl residues are not linked to sulfate groups on the backbone. The backbone →4)GlcUAβ(1 → 3)GalNAcβ(1→ and sulfated fucose branches were composed of the β-d-glucuronic acid, N-acetyl-β-d- galactosamine, α-l-fucose and sulfate groups by the molar ratio of 1:1.72:2.34:3.29. The anticoagulant activities of the HsG was evaluated and compared with heparin. The result showed that the HsG could prolong the activated partial thromboplastin time., (Copyright © 2017. Published by Elsevier B.V.)

The redox reaction between KMnO 4 and Ni was carried out on a chain-like Ni surface under hydrothermal conditions and γ-MnO 2 nanosheets were produced through this facile route. The original Ni nanochains, as cores, dominated the final morphology of the composites with MnO 2 nanosheets loaded on their surface. The uniform assemblies of MnO 2 , with large amounts of exposed sites, allowed them to be good candidates for application in various fields. The reduction of 4-nitrophenol by NaBH 4 was selected as model reaction to test the catalytic activity of the samples and the samples could also be made into electrodes for supercapacitor measurement. Both the results revealed the advantages of the γ-MnO 2 assembled on the Ni chain surfaces. Furthermore, the magnetic cores facilitated the recycling of the sample and increased the stability upon charge-discharge cycles., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Sixteen polycyclic aromatic hydrocarbons (PAHs) were isolated from indoor dust from various categories of rooms in Changchun city, northeast China, including dormitory, office, kitchen, and living rooms. PAH concentrations ranged from 33.9 to 196.4 μg g -1 and 21.8 to 329.6 μg g -1 during summer and winter, respectively, indicating that total PAH concentrations in indoor dust are much higher than those in other media from the urban environment, including soils and sediments. The percentage of five- to six-ring PAHs was high, indicating that PAHs found in indoor dust mainly originate from pyrolysis rather than a petrogenic source. Rooms were divided into three groups using cluster analysis on the basis of 16 PAH compositions, namely smoke-free homes, homes exposed to smoke and offices. Results showed that the source of PAHs in smoke-free residential homes is primarily the burning of fossil fuels. In addition to the burning of fossil fuels, biomass combustion and cooking contributed to PAHs in houses exposed to smoke (including kitchens). Motor vehicles are an additional source of PAHs in offices because of greater interactions with the outdoor environment. The results of health risk assessment showed that the cancer risk levels by dermal contact and ingestion are 10 4 - to 10 5 -fold higher than that by inhalation, suggesting that ingestion and dermal contact of carcinogenic PAHs in dust are more important exposure routes than inhalation of PAHs from air. Although the results showed high potential of PAH concentrations in indoor dust in Changchun for human health risk, caution should be taken to evaluate the risk of PAHs calculated by USEPA standard models with default parameters because habitation styles are different in various categories of rooms.

In this paper, ZnO nanorods-Ag nanoparticles hybrids were first synthesized via a facile, rapid, and in situ plasma sputtering method without using any silver precursor. The obtained materials were then characterized by scanning electron microscopy, high-resolution transmission electron microscopy, energy-dispersive x-ray spectroscopy, and cyclic voltammetry. Based on the electrochemical catalytic properties of the obtained nanohybrids, a non-enzymatic hydrogen peroxide biosensor was constructed by immobilizing the obtained ZnO nanorods-Ag nanoparticles hybrids on the surface of a glassy carbon electrode. Under optimal conditions, the resulting biosensor displayed a good response for H2O2 with a linear range of 0.2 to 12.8 mM, and a detection limit of 7.8 μM at a signal-to-noise ratio of 3. In addition, it exhibited excellent anti-interference ability and fast response. The current work provides a feasible platform to fabricate a variety of non-enzymatic biosensors.

A novel glucosidic pattern of fucose branches was found in the glycosaminoglycan from the sea cucumber Apostichopus japonicus in China. The methylation of desulfated/carboxyl-reduced polysaccharides and analysis of unsaturated disaccharides generated from the enzymolysis of the defucosed polysaccharides demonstrated that the branch is formed by one fucopyranosyl residue, 46.5% of which is linked through the O-3 position of β-D-glucuronic acid, while 8.7% and 43.9% are linked through the O-6 and O-4 positions of the N-acetylgalactosamine moiety. The β-D-glucuronic acid, N-acetyl-β-D-galactosamine, α-L-fucose and sulfate ester with the molecular ratio of 0.97:1.00:1.13:3.85 composed the backbone → 4)GlcUAβ(1 → 3)GalNAcβ(1 → and sulfated fucose branches. The sulfation patterns of fucose branches and the linkage pattern of the backbone structure were determined by 1/2 dimension NMR. The most abundant branch species were 2,4-di-O-sulfated and 3,4-di-O-sulfated fucose, but 4-mono-O-sulfated residue was also present. The structure of presently obtained glycosaminoglycan is different from that previously obtained from Stichopus japonicus (Kariya et al., Carbohyd. Res. 297 (1997) 273-279), which suggests that the structures of glycosaminoglycans from the same species of different regions somehow differ. The anticoagulant assay indicated that the polysaccharide possessed a high anticoagulant activity and the sulfated fucose branches were essential to the activity., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A controlled Cu(2+) catalytic free-radical depolymerization process of fucosylated chondroitin sulfate from sea cucumber Apostichopus japonicus was established. The results showed a good linear relationship between 1/Mw and time during the depolymerization. A series of fractions with different molecular weight were obtained, and the physicochemical properties of them were investigated and compared utilizing the chemical method, IR spectra and NMR spectra. The results showed no significant variations of the backbone and branches structures during the depolymerization. Furthermore, the anticoagulant activities of the depolymerized fractions were evaluated by the activated partial thromboplastin time (APTT). The APTT decreases in proportion to the molecular weight following a linear relationship and the prolongation of APTT activity requires at least oligosaccharide of 4 trisaccharide units (about 4000 Da). Their anticoagulant activity of low molecular weight fraction (Mw = 24,755 Da) is similar to LMWH with significantly less bleeding risk. The results suggest that the low molecular weight fraction could be used as a novel anticoagulant with less undesired side effects., (Copyright © 2014 Elsevier B.V. All rights reserved.)

An ionic liquid-based single-drop microextraction (IL-SDME) procedure using IL as an extractant on-line coupled to capillary electrophoresis (CE) is proposed. The method is capable of quantifying trace amounts of bromophenols in water samples. The extraction parameters such as extraction solvent, extraction time, ionic liquid single-drop volume, ionic strength and organic solvent were systematically investigated. For the SDME of the three bromophenols, a [C4MIM] [ PF6,] microdrop was exposed for 8 min to the aqueous sample with 10% (w/w) NaCI and then was directly injected into a capillary column for analysis. Under the optimal conditions, good linear relationships were obtained in the concentration range of 1 - 100 mg/L with the correlation coefficients of 0. 993 9 - 0. 998 8 for the bromophenols. The detection limits of the three bromophenols were 0. 3 mg/L. The RSDs of peak areas of the standards were 5. 21%- 6.47% (n =6). And the enrichment factors for the three bromophenols were 115.8, 327.0 and 569. 8. The proposed method was applied to the determination of the three bromophenols in tap, river and lake waters with the recoveries of the three bromophenols in the range of 87.8% - 96.7%. The method is suitable for the quantification of bromophenols in water samples.