We prepared moxifloxacin (MXF) loaded nanoparticles by nano-precipitation/self-assembly method, then compared the antibacterial activity of MXF and MXF loaded nanoparticles, and investigated the antibacterial mechanism of MXF loaded nanoparticles against Pseudomonas aeruginosa in vitro. The physicochemical properties such as particle size and zeta potential were investigated by laser particle size analyzer. The in vitro release characteristics were investigated by high performance liquid chromatography (HPLC). The effect of nanoparticles on HBE cells viability was investigated by CCK-8 assay. In addition, the in vitro antibacterial activity was investigated by minimum inhibitory concentration (MIC) assay, biofilm formation assays and transmission electron microscope (TEM) observation, then the antibacterial mechanism was initially explored. The particle size measurement showed that the nanoparticles had a size of 332.5 ±2.7 nm, a polymer dispersion index (PDI) of 0.125 ±0.053, a zeta potential of -24.3 ±1.7 mV, and a uniform particle size distribution, drug loading content was (6.02 ±1.27)%, encapsulation efficiency was (16.69 ±1.17)%. The TEM results show that the nanoparticles have a spheroidal structure, and the particle size and distribution are consistent with the particle size measurement results. The nanoparticles can be effectively and rapidly released in phosphate buffer saline (PBS), releasing about 70% in 24 h, and releasing 87% in 72 h, and almost completely releasing the MXF at 120 h. At the same time, compared with moxifloxacin free drug, its MIC value is 8 μg·mL^-1, which is 1/2 of MXF solution, and can significantly inhibit the formation of bacterial biofilms. It has well antibacterial activity in vitro and can be targeted to the surface of bacteria to exert its efficacy and improve the antibacterial effect. The moxifloxacin nanoparticles prepared in this study has a uniform particle size distribution, well drug release performance and antibacterial effect, and provides new ideas and strategies for the treatment of bacterial lung infection and the development of new antibacterial nanoformulations.

The technology of lipid-drug conjugates is developed on the basis of prodrug principle, which overcomes some drawbacks of drugs via increasing the lipophilicity of hydrophilic or poorly soluble drugs to promote the absorption of drugs and enhance the curative effect. This article sums up the research progress of lipid-drug conjugates from the chemical synthesis methods of conjugates, the types of conjugates, the influence on biological activity of drugs, the application in nanoparticles for drug delivery and the mechanism of absorption and degradation.

Dendrobium officinale Kimura et Migo (D. officinale) has been used as a valuable traditional Chinese medicine for more than 2 000 years in China. Modern research has confirmed a wide range of pharmacological activities, such as regulating blood sugar, improving gastrointestinal inflammation, and regulating immunity. Polysaccharides are the main active ingredients of D.officinale. With the intensive studies of the pharmacological activities of D.officinale, evidence for the pharmacological effects and potential mechanisms of D.officinale polysaccharides has increased dramatically. In this review, we summarized the latest progress in the pharmacological and mechanical studies of D.officinale polysaccharides, and based on the pharmacological efficacy and oral absorption and utilization characteristics of D.officinale polysaccharides, it is proposed that regulating the gut microbiota may be one of the key mechanisms for D.officinale to exert its beneficial effects. Research on the mechanism of D.officinale polysaccharides puts forward new research directions and prospects.

Ischemic stroke is one of the leading causes of death and disability worldwide. A large number of preclinical studies have demonstrated that exogenous cell-based therapies such as mesenchymal stem cell transplantation can promote brain function recovery in the subacute phase of stroke. Emerging data indicate that mesenchymal stem cell-derived exosomes play a key role in mediating tissue repair by participating in intercellular signal transduction and transferring biological information especially microRNA to recipient cells, which affects endo-genous recovery in ischemic brain tissue after injury. In this review we briefly describe the characteristics and biological functions of exosomes and exosomal microRNA, and discuss the therapeutic effects of mesenchymal stem cell-derived exosomes on ischemic stroke from different perspectives. Finally, we outline the potential clinical value of exosomes and challenges of translating these therapies into clinical trials.

Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disease, which is mainly characterized by hyperandrogenemia, rare or anovulation, and polycystic ovarian changes. PCOS is seriously harmful and its causes are complex, which has not yet been clarified. Studies have shown that non-coding RNAs play important roles in the development of PCOS, including the regulation of hormone metabolism and follicle development. Exosomes are natural nano-scale membrane vesicles that contain cell-specific proteins, lipids, nucleic acids, and other biologically active molecules. Exosomes are important mediators for intercellular communication and new targets for disease diagnosis and treatment. Recent studies have shown that as an important component of follicle microenvironment, exosome is closely related to the pathogenesis of PCOS. Exosome and exosomal non-coding RNAs are expected to serve as potential new diagnostic and therapeutic targets for PCOS. In this review, we will summarize the function of exosome and exosomal non-coding RNA in the pathogenesis, diagnosis, and treatment of PCOS.

The tumor contains abundant new vessels, which are unevenly distributed, irregular, and branch-disordered. Angiopoietin (Ang) and tyrosine kinase receptor Tie mediate stable maturation of angiogenesis. Ang1 mainly plays a role in promoting vascular stabilization, and Ang2 is highly expressed in vessels, which makes the structure and function of vessels abnormal. Leaked vessels provide opportunities for invasion and metastasis of circulating tumor cells. Targeting the Ang/Tie axis to correct the abnormal state of vessels and promote its normalization, combined with chemotherapy drugs or immunotherapy, play a synergistic effect against tumors. This article summarizes the role of Ang/Tie axis in tumor angiogenesis and metastasis, and it aims to provide new ideas and strategies for clinical treatment of tumors.

Malignant tumor is a disease that severely threaten human health. Common chemotherapeutical drugs currently used in clinical practice have some problems in severe side effects and chemoresistance. In contrast, natural venom peptides and artificially designed targeting peptides have excellent biological activities and potential druggability due to their small molecular weights and high affinity to tumor tissues. Thus, the methods for the discovery of anti-tumor peptides have attracted much attention. In this paper, we summarized the types of anti-tumor peptides from recent literatures. Then, we systematically reviewed screening theories, methods and applications based on traditional chromatographic separation, peptidomics, phage display, phenotypic screening, and artificial intelligence. These strategies and technologies will provide a methodological reference for accelerating anti-tumor peptides research.

The aim of this research is to investigate the effects of resveratrol on the inflammatory factors, oxidative stress indexes and the related genes of nuclear factor erythroid-2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway in RAW264.7 macrophages induced by monosodium urate (MSU) and to provide a theoretical basis for the treatment of acute gouty arthritis (AGA). Different concentrations of resveratrol were used to treat RAW264.7 cells for 5 hours, then MSU was added to stimulate them for 24 hours. The proliferation of RAW264.7 cells were detected by CCK-8 method. The level of tumor necrosis factor α secreted by cells were detected by ELISA method. The content of reaction oxygen species (ROS) in cells were detected by 2', 7'-dichlorodi-hydrofluorescein diacetate (DCFH-DA) probe method. The contents of superoxide dismutase (SOD) and malonaldehyde (MDA) in cells were detected by the kits. The expression of Nrf2, Kelch like ECH related protein 1 (Keap1), NAD(P)H quinone oxidoreductase 1 (NQO1), HO-1 mRNA were detected by real time PCR method. The results showed that resveratrol could inhibit the proliferation of RAW264.7 cells, significantly inhibit the TNF-α level of RAW264.7 cells induced by MSU, significantly inhibit the expression of ROS and MDA, and increase the expression of SOD in RAW264.7 cells induced by MSU. Resveratrol could reduce the expression of Keap1 mRNA in RAW264.7 cells induced by MSU, and increase the expression of Nrf2, NQO1, HO-1 mRNA. It is suggested that resveratrol can inhibit the inflammatory response of RAW264.7 macrophages induced by MSU, and improve the antioxidant capacity of macrophages by regulating Nrf2/HO-1 signal pathway.

We utilized a multi-step derivatization gas chromatography-mass spectrometry method for the determination of common amino acid enantiomers, combined with deuterated hydrochloric acid hydrolysis, to identify nine trace D-amino acids in thymalfasin. We optimized the conditions for multi-step derivatization, the volume of reagent for redissolving samples, and the conditions for chromatography and mass spectrometry with isopropanol and trifluoroacetic anhydride as derivatization reagents, and validated the procedure, including sensitivity, linear range, precision, accuracy and recovery. Sixteen pairs of D/L-amino acids and glycine derivatives were separated within 29 min, with the limit of quantification as low as 0.09-2.79 μmol·L^-1. Nine amino acid derivatives of thymalfasin showed a good linear relationship within the concentration range examined (r²>0.992 3). The precision results showed that RSD values were less than 10.90%. Accuracy test results of a reference substance ranged from 76.69% to 128.18%. Average recoveries of spiked samples ranged from 70.41% to 125.39%. For the nine D-amino acids assayed, D-Asp and D-Glu content in six batches of thymalfasin were highest, ranging 0.41%-0.49% and 0.25%-0.33%, respectively, with others less than 0.25%. The method is sensitive, efficient and reliable, available for seventeen common amino acids and their enantiomers, and works well with simultaneous determination of nine trace D-amino acids in thymalfasin, providing a reference for the comprehensive control of racemic peptide impurities in this synthetic polypeptide drug.

A high performance liquid chromatography charged aerosol detector (HPLC-CAD) method was established for the simultaneous determination of five saponins (notoginsenoside R1, ginsenoside Rg1, ginsenoside Re, ginsenoside Rb1, Ginsenoside Rd) in Yaobitong capsule, providing a method for quality control. The sample was extracted with methanol and chromatographic separation was performed on a Waters Xbridge Phenol column (150 mm×4.6 mm, 3.5 μm) using acetonitrile-water as the mobile phase with gradient elution at a flow rate of 1.0 mL·min^-1. The column temperature was 30℃ and the injection volume was 10 μL. The nebulizer temperature of CAD was 35℃ and the air pressure was 60.2 psi, the filtration was 3.6 s, and the collection frequency was 5 Hz. Notoginsenoside R1, ginsenoside Rg1, ginsenoside Re, ginsenoside Rb1 and ginsenoside Rd showed a good linear relationship in the range of 16.96-203.5 μg·mL^-1 (R²=0.999 3), 54.46-653.5 μg·mL^-1 (R²=0.999 3), 10.96-131.5 μg·mL^-1 (R²=0.999 6), 51.50-618.0 μg·mL^-1 (R²=0.999 0), 15.94-191.3 μg·mL^-1 (R²=0.999 4), respectively. The average recoveries were 98.96%, 100.8%, 94.76%, 100.1%, 103.1%, and RSDs were 0.87%, 1.46%, 1.85%, 2.06%, 0.96% (n=6), respectively. The proposed method is accurate, simple and reliable, and can be used for the determination of five saponins in Yaobitong capsule.