Latest ArticlesBubali cornu (water buffalo horn) has been used as the substitute for Cornu rhinoceri asiatici (rhino horn) in clinical applications, and is the essential ingredient of Angong Niuhuang Wan. In recent years, there are a number of adulterants on the commercial herbal medicine markets. An efficient tool is required for species identification. In this study, 155 Bubali cornu samples have been taken from original animals and collected from commercial herbal medicine markets. 153 COI sequences have been successfully obtained from 155 samples through DNA extraction, PCR amplification, bidirectional sequencing and assembly. 93 COI sequences have been added to the DNA barcoding database of traditional Chinese animal medicine after validation using DNA barcoding GAP and tree-based methods. The species identification of the 62 commercial Bubali cornu medicines has been accomplished on the DNA barcoding system for identifying herbal medicine using the updated animal medicine database (www.tcmbarcode.cn). Except two samples failed to obtain COI sequences, 54.8% of the commercial Bubali cornu medicines were water buffalo horns and 29% were yak horns. Our results showed that yak horn was the major adulterant of Bubali cornu and the DNA barcoding method may accurately discriminate Bubali cornu and their adulterants. Therefore, we recommend that supervision on the herbal medicine markets should be strengthened with this new method to warren the effectiveness of herbal medicines.
This study was conducted to design and synthetize highly efficient, specific, non-resistant small MEK inhibitors. Based on active small molecules which have been reported, we studied the action mode with MEK protein using Autodock 4.2, generated innovative and feasible design method, designed novel small MEK protein inhibitors with a reference to molecular modeling and docking. The anti-tumor activities of four kinds of cells including MCF-7, PANC-1, SY5Y, A549 were tested with MTT method in vitro. The structure of 10 new small molecules has been determined with 1H NMR and 13C NMR. The compounds 4, 6, 7, 8, 10 had high antitumor activities, the compounds 1, 3, 5 also showed good activity, and the compounds 2, 9 showed cell selectivity in killing tumor.
With the method of fluorescence polarization (FP), we screened small molecule inhibitors for PLK1 PBD to identify the lead compounds for antitumor drugs. FP led to the identification of a potent hit, F083-0063, whose inhibition rate was (99.7±0.4)% at 10 μg·mL-1. The IC50 was calculated to be 1.9±0.1 μmol·L-1 using Graphpad Prism 5. The effect of the compound on cells' multiplication was measured by MTT assay which showed that F083-0063 inhibited the proliferation of many tumor cell lines. Flow cytometry analysis indicated that the F083-0063 promoted cell apoptosis and induced cell G2/M arrest. Migration abilities of cells, evaluated using scratch test, increased significantly in the presence of F083-0063 with the mi-gration rate as low as (37.6±0.7)% at 20 μmol·L-1. Molecular linkage technique found F083-0063 had good affinity with PLK1 PBD. The results of Western blotting showed that the expression of cyclin-dependent proteins was increased after treatment with F083-0063. In summary, F083-0063 has an antitumor activity and is expected to be an antitumor lead compound targeting PLK1 PBD.
In this study, the endocytosis pathway of heparosan and its intracellular distribution were investigated in MCF-7 tumor cells and COS7 normal cells. The endocytosis inhibition and cellular probe location experiments showed that MCF-7 tumor cells took heparosan more efficiently and selectively than COS7 cells. The cellular uptake of heparosan was energy-dependent in both MCF-7 tumor cells and COS7 normal cells. Moreover, the major endocytosis pathway of heparosan into MCF-7 tumor cells was caveolin-mediated endocytosis and macropinocytosis. The internalized heparosan was mainly located in lysosomes of the cells.
A new method was developed for the chromatographic fingerprint analysis of Toosendan Fructus by HPLC coupled with the charged aerosol detector (CAD) in the present study. Samples were well separated on an Agilent ZOBAX SB C18 column (4.6 mm×250 mm, 5 μm) by gradient elution using acetonitrile and water containing 0.1% formic acid (v/v) at the flow rate of 1.0 mL·min-1. The column temperature was 30℃ and the injection volume was 5 μL. The nitrogen inlet pressure of the charged aerosol detector (CAD) was 35 psi, and the nebulizer chamber temperature was 35℃. In addition, the method of the chromatographic fingerprints combined with multivariate statistical analysis was effective and reasonable lead to an accurate classification of 20 batches of samples from different locations. The results showed that 28 common peaks were observed in the fingerprint and the samples were classified into three clusters. The established method was well validated, and showed high precision, good repeatability, and satisfactory stability. It may serve in the quality control and evaluation of Toosendan Fructus.
Transglutaminase (TG) posttranslational modification of antibody permits more precisely conjugating. Based on the amino acid sequence of an anti-CD24 antibody (cG7), this article is aimed to generate a deglycosylated cG7 mutant (cG7Q). Firstly, we introduced additional glutamines at position 297 (N297Q) by site-directed mutagenesis, and then transfected the recombinant plasmids into CHO-s cells via electroporation method and screened by Dot blot assay. Subsequently, cG7Q was expressed and purified through Protein A affinity chromatography, further identified by SDS-PAGE electrophoresis and Western blot. Its affinity was detected with surface plasmon resonance and flow cytometry assay, and ADCC effect was determined by lactate dehydrogenase (LDH) release. Eventually, a cG7 mutant, cG7Q was successfully expressed with sequence-specific conjugation sites for further study.
Population pharmacokinetics is an emerging discipline developed from the combination of classical pharmacokinetic compartment model and statistics principles, which has been received more and more attention in recent years. Population pharmacokinetics plays important roles in all stages of new drug research. In the early preclinical phase, population pharmacokinetic analysis can help to achieve the preliminary prediction of parameters from animal to human, optimize clinical trial designs, and shorten the time required for new drugs from laboratory to clinical trials. In clinical trials and applications stage, population pharmacokinetic research can help researchers investigate the related covariates that affecting pharmacokinetic behavior of patients comprehensively, and find potential drug-drug interactions in clinical. In addition, population pharmacokinetics has a unique advantage in pediatric drug development due to its strong analysis ability of sparse data. This paper provides a summary on the history and methods of population pharmacokinetics, and the application in new drug discovery and development.
In recent years, owing to the abuse of antibiotics, the widespread of resistant bacterial strains became a serious threat to public health. This status demands development of new antibacterial agents with novel mechanisms of action. The reason for the limited new antibacterials is the small number of effective therapeutic targets, which cannot meet the current needs for the multiple drug-resistant treatment. Screening for new targets is the key step in the development of novel antibacterial agents. Peptidoglycan is the main component of the cell wall of bacteria, which is essential for survival of pathogenic bacteria. Within the biochemical pathway for peptidoglycan biosynthes is the Murligases, described in this review as highly potential targets for the development of new classes of antibacterial agents. This review provides an in-depth insight into the recent developments in the field of inhibitors of the Mur enzymes (MurA-F). Moreover, the reasons for the lack of candidate inhibitors and the challenges to overcome the hurdles are also discussed.
This study was conducted to test the effects of schizandrin B (Sch B) on clozapine (CLZ) induced chronic liver injury in mice and the mechanism of action, and this may provide a new approach for clinical prevention of CLZ-induced side effects. The CLZ was given to mice for three weeks alone or co-administration with Sch B. The changes of alanine aminotransferase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP) and antioxidation indexes superoxide dismutase (SOD), malonic dialdehyde (MDA), glutathione (GSH) and liver histological evaluation were determined. Expression of Nrf2 was assayed in hepatic cells by immunohistochemical staining and Western blotting. The changes of relative gene expression of NAD (P) H:quinone oxidoreductase l (NQO1) and heme oxygenase 1 (HO-1) were assayed by real-time Q-PCR. The results showed that pretreatment with a lower dosage of Sch B (25, 50 mg·kg-1) prevented CLZ-induced liver injury as indicated by the reduced levels of ALT, AST and ALP, and the preserved activities of SOD, GSH and inhibiting MDA. It was shown that Sch B could up-regulate Nrf2 expression leading to nuclear accumulation of Nrf2 to induce oxidative response genes such as NQO1 and HO-1. These results suggest that Sch B could protect against liver injury induced by CLZ via the activation of the Nrf2/ARE signal pathway in a dose-dependent manner.
A type Ⅱ ribosome inactivating protein (RIP) gene was cloned from Polyporus umbellatus sclerotia by RT-PCR method. The full open reading frame cDNA sequence of this gene was 873 bp in length and encoded a 290-aa protein with a molecular weight of 32.33 kDa and an isoelectric point of 5.58. Multiple sequence alignment revealed that the deduced amino acids possessed conserved domains of RICIN superfamily protein. A neighbor joining phylogenetic analysis suggests that PuRIP was closely related to RIP in Marasmius oreades. Real time PCR results showed that this gene expressed in all tested tissues of P. umbellatus. Meanwhile, the expression of this gene was significantly up-regulated in the part infected by Armillaria mellea. This result suggested that this PuRIP might played important role with potential biotic stress tolerance of P. umbellatus. Otherwise, we successfully constructed the pET15b-PuRIP plasmid, produced and purified the His-PuRIP fusion protein, which would provide the basic material for polyclonal antibody preparation and gene function research.
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