Liquid chromatography-tandem mass spectrometry (LC-MS) is a promising alternative or complementary method for traditional ligand-binding assays (LBA) in antibody drug bioanalysis. However, issues related to method development, sample preparation, sensitivity and quantitative accuracy need to be addressed. This paper reviews progress in bioanalysis of antibody drugs by LC-MS methods, introduces the principle of the LC-MS method for the analysis of antibody drugs, and describes the challenges faced in quantitative antibody analysis by the LC-MS method. New strategies that can be used to deal with these challenges include:selection of surrogate peptides, purification and enrichment of samples, improvement in enzymatic digest efficiency, enrichment of peptides, and use of low rate LC. We review the application of LC-MS technology in the biological analysis of antibody drugs and discuss the prospect of using the LC-MS method for the analysis of antibody drugs.

This study aimed to investigate the effect of the petroleum ether fraction of Xiaoyaosan (XY-A) in a rat depression model with consideration of an underlying mechanism based on gut microbiota and metabolomics. All procedures involving animal treatment were approved according to the Committee on the Ethics of Animal Experiments of Shanxi University. A rat model was established using the chronic unpredictable mild stress (CUMS) procedure and XY-A and venlafaxine (positive control) were used as intervention drugs. Sequencing of the 16S rRNA gene combined with LC-MS metabolomics was used to investigate the effects of XY-A on gut microbiota and metabolites in CUMS-induced depression, and Pearson correlation analysis was carried out on gut microbiota and metabolites. The results showed that XY-A significantly improved the depression-like behavior of CUMS rats and restored the level of brain-derived neurotrophic factor (BDNF) in the hippocampus. Gut microbiota analysis revealed that XY-A can increase the diversity of microbial species in CUMS rats and significantly restored the relative abundance of intestinal Rothia [Prevotella], with effects on intestinal inflammation and the production of short-chain fatty acids. Cecal content metabolomics identified twenty biomarkers that were altered by depression, whereas administration of XY-A ameliorated the changes in seventeen metabolites, with the most strongly affected metabolic pathways being linoleic acid metabolism, taurine and hypotaurine metabolism, primary bile acid biosynthesis, and arginine and proline metabolism. Correlation analysis further showed that there was a strong relationship between the gut microbiota and the cecal content metabolites. In summary, XY-A may exert antidepressant effects by regulating the composition of the gut microbiota and the metabolites and pathways of the cecum. The results provide a reference for the potential molecular mechanism of antidepressant action of XY-A.

To explore the affect and mechanisms of rapamycin on mesangial cell proliferation and cell cycle, rat mesangial cells (HBZY-1) were cultured and divided into the six groups:normal; normal with platelet derived growth factor (PDGF) 20 ng·mL^-1; PDGF + rapamycin 1, 10, 100, 1 000 nmol·L^-1. The cell proliferation was measured by MTT in 24 and 48 h; flow cytometry was used to detect the cell cycle phase. Western blot was performed to determine cyclin D1, cyclin E, cyclin-dependent kinase 2 (CDK2), cyclin-dependent kinase 4 (CDK4), p27, p70S6K/p-p70S6K protein expression. The p27 mRNA was detect by Real-time PCR. The results showed that rapamycin significantly suppressed PDGF induced glomerular mesangial cells (MCs) proliferation in a dose and time-dependent manner, but with the dose increased (1 to 1 000 nmol·L^-1), the time dependence gradually weakened. Rapamycin inhibited mesangial cell proliferation and arrested the cell cycle in the G0/G1 phase. PDGF at 20 ng·mL^-1 significantly increased the expression of cyclin D1, cyclin E and CDK2, CDK4 (P < 0.05), but rapamycin did not affect the expression of cyclin D1, cyclin E and CDK2, CDK4. Rapamycin can significantly inhibited p70S6K phosphorylation, up-regulated the expression of p27 protein and mRNA. Collectively, rapamycin has the effect of inhibiting the glomerular mesangial cells proliferation of mesangial cells by regulating the transcription of p27 mRNA, increasing its protein expression through the mTORC1/p70S6K pathway, resulting in decreased activity of cyclin-CDK, and blocking cell cycle in G0/G1 phase.

Oral transmucosal drug delivery can be defined as the administration of drug through the oral mucosa to achieve systemic effects. It has the advantages of high bioavailability and rapid drug response. In this review, we introduce the physiology of oral mucosa, and analyze the factors affecting the pharmacokinetic properties of oral transmucosal drug delivery in detail, such as physiological barriers, different administration sites, physicochemical properties of drugs, dosage forms, and formulation strategies. In addition, we describe the methods to evaluate the pharmacokinetic properties of this delivery systems, including in vitro permeability studies, buccal absorption studies, in vivo pharmacokinetic studies and physiologically based pharmacokinetics (PBPK) modeling, which provide methods and reference for the development of oral transmucosal drug delivery systems.

The objective of this research was to clone 1-deoxy-D-xylulose 5-phosphate reductoisomerase gene (MoDXR) and its promoter sequence from Morinda officinalis and carry out bioinformatic analysis, cis-acting elements analysis, and prokaryotic expression. On the basis of the MoDXR gene sequence obtained from the M. officinalis transcriptome and with NCBI-ORFfinder analysis, a pair of specific primers were designed, and used for RT-PCR amplification. The promoter region sequence at the 5' end of MoDXR gene was isolated by the genome walking technique. Localization of MoDXR was carried out by subcellular analysis. The prokaryotic expression plasmid pET-28a-MoDXR was constructed and transfected into Escherichia coli BL21(DE3) chemically-competent cells; the recombiant plasmid expressed fusion protein after the induction by IPTG. The full-length cDNA of MoDXR was 2 015 bp, and open reading frame (ORF) size was 1 425 bp, and it encoded 474 amino acid residues and had a molecular mass of 51.27 kD. Sequence comparison with BlastP to the NCBI database revealed that MoDXR had high sequence similarity with many other DXRs, such as Coffea arabica DXR (CaDXR) and Rauvolfia verticillata DXR (RvDXR). A phylogenetic tree revealed that MoDXR had its closest relationship with DXR from Coffea arabica and Gardenia jasminoides. The subcellular localization revealed that MoDXR protein was located on the chloroplast. Plantcare analysis indicated that the promoter region sequence of MoDXR was 1 493 bp, covering multiple light, stress, and hormone-responsive cis-regulatory elements; protein electrophoresis showed that the expressed protein was the anticipated size. This research lays the foundation for further purification and structural and functional characterization of the MoDXR protein.

Drug screening against Candida albicans has become more urgent due to the increasing incidence of infection and the development of drug-resistant strains. The microfluidic chip technique has shown great potential for high-throughput drug screening. In this study we developed a concentration gradient microfluidic chip platform for drug screening against Candida albicans. The generated concentration gradient on this platform was investigated qualitatively by monitoring the distribution of the fluorescent tracer fluorescein sodium and quantitatively by following the distribution of the model drug fluconazole as analyzed by HPLC; the effect of different flow conditions on the concentration gradient were determined. The ratio of the two aqueous phase flow rates was determined in the subsequent drug screening studies. Alamar Blue, an indicator of cell viability, was used in the susceptibility test for amphotericin B, fluconazole, itraconazole, voriconazole, posaconazole, terbinafine, 5-fluorocytosine and caspofungin as carried out on the established chip platform. The MIC range of the drugs, which was consistent with the MIC values of the CLSI-recommended standard, were obtained quickly and efficiently through the use of this platform, indicating that this new platform can quickly screen a series of antibacterial drugs in one run. In addition, the strain of Candida albicans we used showed resistance to terbinafine in our platform assay, consistent with the results of a 96-well plate assay, indicating that the platform can also be used for rapid screening of resistant strains.

The chemical constituents of Rehmanniae Radix Preparata were prepared according to the traditional method of "jiu zheng jiu shai" and investigated using multiple chromatographic methods. Six alkaloids were isolated and their structures were elucidated from spectral data and physicochemical properties, as follows:rehmanniae alkaloid A (4-{[(5-O-á-D-galactopyranosyloxy)methyl]-1H-pyrrole-2-carbaldehyde-1-yl}butyric acidmethyl ester) (1), baimantuoluoamide B (2), capparisine C (3), harman-3-carboxylic acid (4), (2S)-1-[2-(furan-2-yl)-2-oxoethyl]-5-oxopyrrolidine-2-carboxylate (5), and 1-[2-(furan-2-yl)-2-oxoethyl]pyrrolidin-2-one (6). Among them, compound 1 is a new alkaloid. Compounds 2-6 were newly isolated from Rehmannia glutinosa Libosch. The effect of compounds 1-6 on NRK-52e cell injury induced by LPS was investigated. The results show that compounds 1-3 exhibit protective effects against LPS-induced damage to NRK-52e cells.

Eight triterpenes were isolated from the methanol extract of Galbanum by various chromatographic methods including silica gel, ODS opening column, recrystallization and semi-preparative HPLC. Their structures were determined by spectroscopic methods and physicochemical properties as 3β, 19α, 21α-trihydroxyl-12-en-28-oic acid (1), sumaresinolic acid (2), 3β, 19α-dihydroxyl-12-en-28-oic acid (3), oleanolic acid (4), 3β, 6β, 19α-trihydroxyl-12-en-28-oic acid (5), 19α-hydroxy oleanonic acid (6), 6α-hydroxy oleanonic acid (7), and (11R, 12R)-3α, 6α-dihydroxy-epoxyolean-28α, 13α-olide (8). Among them, compound 1 is a new compound, while compounds 2-8 were newly isolated from the Apiaceae family. The ability of compounds 1-8 to inhibit cholinesterase was determined with an improved Ellman method. Compound 1 showed strong inhibitory activity against butyrylcholinesterase. The molecular docking results indicated that Trp82, His438, Phe329 and Ala328 played an important role in the binding of compound 1 to butyrylcholinesterase.

Neuropathic pain (NP), as a kind of chronic pain syndrome, seriously endangers the quality of life of patients, and the pathogenesis is complex, clinical treatment is limited, and it is easy to relapse. More and more reports have found that Wnt signaling pathway is closely related to the occurrence and development of neuropathic pain. Therefore, further study of the Wnt signaling pathway may provide useful ideas for exploring the pathogenesis of NP and discovering effective treatment methods. This article reviews the role and mechanism of Wnt signaling pathway in neuropathic pain.

There is no specific drug that has been approved for 2019-nCoV. There are a number of factors that pose major challenges in their development. Approaches to the development of anti-2019-nCoV include screening existing broad-spectrum antiviral drugs, repositioning of readily available clinical compounds, and de novo development of novel and specific agents for 2019-nCoV. Candidate compounds can be developed either to inhibit virus-based targets, such as RNA proteases, polymerase, spike glycoproteins, and viral envelop and membrane proteins, or to inhibit host-based targets, such as receptors and proteases that are utilized by virus for viral entry and endocytosis. Recently, the RNA polymerase remdesivir had demonstrated clinical efficacy in one patient with severe novel coronavirus pneumonia (NCP). The broad-spectrum viral protease inhibitor Kaletra^® is also recommended in the current NCP clinical practice. Both drugs had lately been proceeded into multiple controlled phase Ⅲ clinical trials to test their safety and efficacy in NCP. Combinational therapies consisting of multiple drugs provide other viable options against 2019-nCoV, based on scientific and clinical rationales. Using bioinformatics and database analysis, we have identified 75 clinically compounds, including 20 marketed compounds, that are efficacious in inhibiting key targets in virus- and host-based approaches, which may facilitate the development of new therapeutic options for 2019-nCoV.