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Objective@# To investigate the effects of graphene on the proliferation, migration and cell morphology of dental pulp stem cells (DPSCs).@*Methods@#Graphene powder was prepared by the oxidation-reduction method, and a 0.5 mg/mL graphene dispersion was prepared. Raman spectroscopy and atomic force microscopy were used to characterize the structure and surface morphology of graphene. DPSCs were isolated and cultured in vitro. MTT assay was used to detect the effects of different concentrations of graphene dispersions (0, 1, 5, 10, 20, 50, 100 μg/mL) on the proliferation and wound healing assay was used to detected the migration abilities of DPSCs. The effects of graphene on the morphology of DPSCs were observed by immunofluorescence staining. @*Results @# In the present study, compared with the control group (0 μg/mL), the proliferation of DPSCs in the 100 μg/mL group was inhibited at 72 h (P < 0.05), and the proliferation of DPSCs in the other groups was not significantly affected (P > 0.05). Graphene dispersions at 10 and 20 μg/mL promoted the migration of DPSCs (P < 0.05). After being cultured in 20 μg/mL graphene dispersions for 3 days, the DPSCs showed a large and orderly cytoskeletal structure, and the spread area of cells was not significantly different from that of the control group (0 μg/mL) (P > 0.05), while some cells had the morphological characteristics of nerve cells.@* Conclusion @# Graphene has good biocompatibility and is expected to be a suitable material for tissue engineering within fitting concentration.
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Objective:To isolate and purify a polysaccharide CALB-2 fraction from Aurantii Fructus，and analyze its basic chemical structure, morphological characteristics and bioactivity. Method:A refined CALB-2 was obtained from Aurantii Fructus by hot water extraction，then separated and purified by ion exchange resin，ion exchange agarose gel and propylene dextran gel to obtain homogeneous polysaccharide CALB-2. The molecular mass of CALB-2 was determined by high performance liquid chromatography （HPLC）. Monosaccharide composition analysis of CALB-2 was conducted by methylation analysis and Smith degradation. Structural analysis and morphological characterization were conducted by infrared scanning （IR） and scanning electron microscopy （SEM） analysis. Antioxidant activity of CALB-2 was studied by using H2O2-induced cardiomyocyte oxidative damage model. Result:CALB-2 was a homogeneous polysaccharide and the molecular weight of CALB-2 was estimated to be 3.57×107 Da，which was proved to be a kind of highly branched acidic polysaccharides in IR analysis, methylation analysis and Smith degradation, mainly present in form of 1→3，4 bonds. Through SEM observations，we indicated that the molecular morphology of CALB-2 was amorphous solid. The in vitro activity test showed that CALB-2 had obvious protective effects on injury of H9c2 myocardial cells induced by H2O2. Conclusion:CALB-2 is a kind of homogeneous polysaccharide extracted from Aurantii Fructus， with an anti-cardiomyocyte oxidative damage effect, laying a theoretical foundation for further study of Aurantii Fructus polysaccharides．
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The research and development of monoclonal antibodies (mAbs) is a rapidly developing field. From the first generation of murine mAbs to the fourth generation of fully human mAbs, the efficacy and safety of mAbs in the treatment of various diseases have been continuously improved. In order to regulate the development and evaluation of mAbs, drug regulatory agencies and pharmacopeias of America and China have tried to issue feasible test procedures and acceptance criteria for quality evaluation of mAbs and biosimilars. Mass spectrometry (MS) technique with high sensitivity, resolution, selectivity, and specificity has become an important tool to evaluate the quality characteristics of monoclonal antibody-related products or specify mAb quality. The research of MS-based monoclonal antibody study involves structure characterization, impurity analysis, pharmacokinetics/pharmacodynamics (PK/PD), etc. This review focuses on the current quality control requirements of mAb related products and the development of MS technique for mAb quality characterization and specification. It is expected to provide information and references for evaluating the quality of monoclonal antibodies under research and development.
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Objective: To extract and isolate polysaccharide from Cyclocarya paliurus leaves, characterize its structural features and study its α-glucosidase inhibitory effect. Methods: C. paliurus polysaccharide (CP50) was isolated and purified by water extraction and ethanol precipitation, deproteinization with 732 cation exchange resin and 50% ethanol precipitation. Molecular weight of CP50 was determined by high performance gel permeation chromatography-multiple angle laser light scattering (HPGPC-MALLS), and monosaccharide composition was analyzed by HPLC with PMP (1-phenyl-3-methyl-5-pyrazolone) pre-column derivatization. The structure of CP50 was characterized by methylation, Fourier transform infrared spectroscopy (FT-IR), and proton nuclear magnetic resonance spectrum (1H-NMR), respectively. The α-glucosidase inhibitory effect of CP50 was investigated by PNPG method. Results: The molecular weight of CP50 was 59 000. It contained eight kinds of monosaccharides including galacturonic acid, glucose, galactose, arabinose, mannose, xylose, rhamnose, and glucuronic acid with molar ratio of 29.1:25.6:16.5:9.3:6.7:6.1:4.1:2.6. CP50 was mainly composed of →4) GalA (1→, →4) Glc (1→ and →4) Gal (1→ with branches at C-6 position of galactose. Furthermore, our results showed that CP50 exhibited a potent inhibitory effect on α-glucosidase, and the value of IC50 was determined to be 3.3 μg/mL which was much lower than the anti-type 2 diabetes drug acarbose (193.6 μg/mL). The inhibitory mode belongs to the mixed noncompetitive inhibition. Conclusion: CP50 is a pectin-like acidic polysaccharide with complex structure. Moreover, CP50 possesses better α-glucosidase inhibitory effect and potential value for the drug development and utilization.
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Based on the theory of topological structure within the syndrome of tradition Chinese medicine (TCM), the high order multiple dimensions and nonlinear structure of syndrome can be cracked. And the panorama of complex and changeable syndrome can be showed. The dynamic evolving law of sub-sets of syndromes and the changing rule of the main signs and symptoms with the secondary signs and symptoms can be interpreted. Therefore, the evolving law of sub-sets of syndromes and the accurate corresponding law of prescriptions and medicines can be realized. And the scientific connotation of dynamic evolving rule of syndrome can be revealed. Studying on the occurrence regularity of syndrome, the structure characterization of TCM syndrome can be carried out. And the mathematical structure-physical structure-biological structure can be revealed. Along with the mass new specific forms of syn-dromes to be cracked, the simulation data platform of therapeutic methods with prescriptions and medicines of syn-dromes can be built through the simulation technology of computer. Using the clinical data, through the literature of carding and contrast, the scientific connotation of judgment and diagnostic standard of syndromes can be interpreted. The distracting law of syndromes of diseases can also be revealed through the clinical data of syndrome-groups. And the theoretical basis for the formulation of judgments and diagnostic standard of syndromes of diseases which con-forming to the dynamic evolving law of syndromes can be provided. Evaluation on TCM efficacy can be carried, in order to make clear the curative effect evaluation index system of TCM syndrome in multiple dimensions and multi-ple levels for the promotion of the substantially improvement of syndrome differentiation level.
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AIM@#To study the related impurities in asperosaponin VI bulk drug and to develop a high performance liquid chromatography (HPLC) method for the determination of asperosaponin VI and its related impurities.@*METHODS@#The related impurities were detected in asperosaponin VI bulk drug by a newly developed HPLC method, obtained by ODS column chromatography and semi-preparative HPLC methods, and the structures were elucidated by TOF-MS, IR, and NMR techniques. The HPLC method was validated according to ICH guidelines for asperosaponin VI and its related impurities.@*RESULTS@#Seven related impurities (Imp 1-7) were isolated from asperosaponin VI bulk drug. Impurity 3 was found to be a mixture of two epimers, and was first reported in the paper. The validation results showed good sensitivity, specificity, linearity (r(2) ≥ 0.997 9), precision (RSD < 5.0%), accuracy (recoveries in the range of 94.61%-106.51%) and robustness.@*CONCLUSION@#The developed HPLC method is suitable for the quality control of asperosaponin VI bulk drug.
Subject(s)
Chromatography, High Pressure Liquid , Methods , Drug Contamination , Magnetic Resonance Spectroscopy , Mass Spectrometry , Molecular Structure , Saponins , ChemistryABSTRACT
Poly(ethylene glycol)(PEG) coated silver nanowires has been hydrothermally prepared at a very slow rate, in which PEG was used as both a mild capping agent and a weak reductant. As-prepared silver nanowires(SNWs) have been characterized using scanning electron microscopy) and transmission electron microscope), which showed that the SNWs are usually longer than 100 μm and their diameters(each SNW has a uniform thickness) vary mainly in the range of 80～300 nm. Surprisingly, some of these silver nanowires connected) by their two ends to form some close-looped silver nanowires, which hitherto has not been reported elsewhere. The existence of close-looped silver nanowires supports the mechanism that nanowires can evolve from fusion of some nanoparticles and/or shorter nanorods. Careful TEM characterization and selected area electron) diffraction revealed that the silver nanowires kept a five-fold twinned structure, which is opposite to some reports) that a long-time incubation will lead to the disappearance of this twin structure. This work demonstrates the situation that deeper investigation is still needed for understanding the structure transformation of silver) nanowires.
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The microbial populations and community structure characterization technologies of the enhanced biological phosphate removal system were reviewed comprehensively in this paper, and their future research directions were outlined.