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The discrimination and determination of small organics may be employed for baijiu identification. A single nanoparticle was designed as a fluorescence sensor to address this issue. Via specific host-guest interactions, small organics may significantly disrupt the energy transmission of nanoparticles, resulting in sharp changes in characteristic fluorescence peaks, thus allowing the discrimination of single substances or mixtures by principal component analysis (PCA), hierarchical clustering analysis (HCA), and linear discriminant analysis (LDA). The system was characterized by transmission electron microscopy with energy dispersive spectrometry and fluorescence spectroscopy. 15 small flavor organics in baijiu were successfully discriminated. Moreover, the linear relationship between the concentrations of tryptophan and ethyl butyrate with the corresponding responsiveness demonstrated the capabilities of the sensor. The reported device was successfully applied to distinguish 16 baijiu brands. This simple and rapid method has outstanding potential for the characterization of alcoholic beverages. [ABSTRACT FROM AUTHOR]

The anti-infection ability and skin regeneration are important aspects on the progress of wound healing, which needs an ideal wound dressing that not only resists bacteria but also promotes skin regeneration. In this study, zinc oxide/silver/polyvinylpyrrolidone/polycaprolactone (ZnO/Ag/PVP/PCL) nanofibres were prepared through electrospinning. Firstly, zinc oxide nanoparticles (ZnONPs) and silver nanoparticle (AgNPs) were synthesized respectively. Secondly, the two nanoparticles were mixed with polyvinylpyrrolidone (PVP) and polycaprolactone (PCL) to obtain the nanofibres. The results of scanning electron microscopy (SEM) showed that ZnONPs and AgNPs were 40.07 ± 9.70 nm and 37.46 ± 12.02 nm, respectively. After electrospinning, the nanofibres were 368.22 ± 123.96 nm in diameter. Infrared spectroscopy revealed that ZnONPs/AgNPs bimetallic nanomaterials were physically embedded in the nanofibres. The antibacterial effects against Staphylococcus aureus and Escherichia coli of ZnO/Ag/PVP/PCL nanofibres were significantly better than these of the single metal material-loaded nanofibres. More importantly, the combination of ZnO and Ag reduced the cytotoxicity of ZnO/Ag/PVP/PCL bimetallic nanofibres toward fibroblasts. These findings demonstrated that ZnO/Ag/PVP/PCL bimetallic nanofibres should be of greater interest than the single metal nanomaterial-loaded nanofibres in inhibiting growth of bacteria. [ABSTRACT FROM AUTHOR]

This study reports on the performance of sodium alginate (SA)/poly(vinyl alcohol) (PVA)/moxifloxacin hydrochloride (MH) nanofibrous membranes (NFM) capable of providing antibacterial agent delivery for wound-dressing applications. The aim of this work was to prepare antibacterial NFM with good permeability properties by employing PVA and SA as carriers. A group of 12% PVA/2% SA solutions blended in various ratios (8:2, 7:3, 6:4, 5:5 and 4:6, v/v) and containing 0.5, 1, 2 or 4 wt% MH were studied for electrospinning into nanoscale fibermats. The optimum ratio found to form smooth fibers with uniform fibrous features was 6:4. The drug release behavior of the electrospun, the antibacterial effects onPseudomonas aeruginosaandStaphylococcus aureusand the animal wound dressing capabilities were also investigated. As much as 80% of the MH was released from the electrospun after 10 h of incubation at 37 °C. In addition, the NFM with 0.5 MH exhibited less activity, whereas those with higher concentrations of MH exhibited greater antibacterial effect. Furthermore, the MH-loaded electrospun accelerated the rate of wound dressing compared to other groups. The results of thein vitroandin vivoexperiments suggest that MH/PVA/SA nanofibers might be an interesting bioactive wound dressing for clinical applications. [ABSTRACT FROM PUBLISHER]

A new diketopiperazine (DKP) derivative, (6R,3Z)-3-benzylidene-6-isobutyl-1-methyl piperazine-2,5-dione (1), as well as five known DKPs 2–6 was isolated from a deep sea-derived Streptomyces sp. SCSIO 04496. The structure of 1 was elucidated using a combination of 1D and 2D NMR, HR-ESI-MS and chiral-phase HPLC techniques. Compounds 1–6 did not show cytotoxic activity at a concentration of 100 μM in bioactivity assay. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of modified bone morphogenetic protein-2 polylactic acid nanospheres (BMP-2-PLA-Ns) sustained-release system on rabbit mandibular defect repair. Methods The polylactic acid snanospheres (PLA-Ns) and BMP-2-PLA-Ns were prepared by ultrasonic emulsification after graft polymerization. Forty-five rabbits were randomly divided into 3 groups: Blank group, PLA-Ns gel group (control group), and BMP-2-PLA-Ns gel group (experimental group). The rabbit mandibular defect models were established. The defect area of control group was implanted with PLA-Ns gel, meanwhile, the experimental group was implanted with BMP-2-PLA-Ns gel, the blank group experienced no special handling. Rabbits were killed in 1, 2, 4 weeks after operation and the iconography, hematine eosin (BE) staining and PCNA immunohistochemistry were used to detect the reparative effect on rabbit mandible defects. Results Image observation showed that bone defect repair in the experimental group was well and the shadow was not obvious. Better repair effect was seen compared with the control group and blank group. HE staining showed that the experimental group and the control group had a large number of neovascularization and secon- dary callus formation, callus in experimental group was obviously higher than that of control group and blank group. Immunohistochemical observation showed that the experimental group's PCNA positive chondrocytes were more than those in the control group and the blank group in the first 2 weeks; all groups of PCNA positive cells were rare in the fourth week, PCNA positive expression rate of the fourth week was lower than that of the first 2 weeks. Conclusion The modified BMP-2-PLA-Ns sustained-release system promotes mandibular defect repair obviously. [ABSTRACT FROM AUTHOR]

Cu 2- x Se nanoparticles (Cu 2- x Se NPs) as a new therapeutic drug platform is widely used in disease treatment due to their strong near-infrared optical absorption. In recent years, with their continuous expansion of applications in different fields, their own biological effects have received increasing attention. However, little is known about the effect of Cu 2- x Se NPs on cancer cell. In this research, we found that Cu 2- x Se NPs inhibited proliferation of HepG2 cells (IC50: 15.91 μ M) and SMMC-7721 cells (IC50: 43.15 μ M) and they mainly induced cell cycle arrest at the G2/M phase. Moreover, Cu 2- x Se NPs inhibited HepG2 and SMMC-7721 cell migration and lamellopodia formation. Further studies indicated that Cu 2- x Se NPs impaired mitochondrial respiration by inhibiting electron transport chain complex activity, thus reducing adenosine triphosphate levels. The insufficient energy supply subsequently impaired actin cytoskeleton assembly, ultimately inhibiting HepG2 and SMMC-7721 cell proliferation and migration. These findings suggest that Cu 2- x Se NPs may have potentially antitumor activity, which might provide new insights of NPs into specific cancer treatment., (© 2023 IOP Publishing Ltd.)

In this study, a mixture of poly(vinyl alcohol) (PVA) and chitosan oligosaccharides (COS) was electrospun with silver nanoparticles (AgNPs) to produce fibrous mats for use in wound healing. The AgNPs were reduced by COS prior to electrospinning or Ag(+) was reduced via ultraviolet irradiation in nanofibers. The morphologies of the PVA/COS/AgNO3 and PVA/COS-AgNP nanofibers were analyzed by scanning electron microscopy. Formation of the AgNPs was investigated by field emission transmission electron microscopy, ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. We also evaluated the biocompatibility of the nanofibers, particularly their cytotoxicity to human skin fibroblasts and potential to cause primary skin irritation. The in vitro antibacterial activity and in vivo wound healing capacity of the nanofibers were also investigated. The nanofibers had a smooth surface with an average diameter of 130-192 nm. The diameters of the AgNPs were in the range of 15-22 nm. The nanofibers significantly inhibited growth of Escherichia coli and Staphylococcus aureus bacteria. PVA/COS-AgNP nanofibers accelerated the rate of wound healing over that of the control (gauze). The results of our in vitro and in vivo animal experiments suggest that PVA/COS-AgNP nanofibers should be of greater interest than PVA/COS/AgNO3 nanofibers for clinical use as a bioactive wound dressing.