1. The role and mechanism of graphene and its derivatives-related composites in cartilage repair
Chinese Journal of Tissue Engineering Research 2020;24(4):619-624
BACKGROUND: Graphene-related materials have good biocompatibility and can improve cartilage repair. At the same time, their excellent mechanical strength and electrical conductivity make them promising as cartilage replacement materials, which have been widely used in tissue engineering. OBJECTIVE: To review the general properties, biocompatibility and application of graphene in cartilage tissue engineering and cartilage repair. METHODS: A computer-based online search of CNKI and PubMed databases was performed using the search terms “graphene, tissue engineering, biocompatibility, cartilage” in Chinese and English to search related literatures published between January 2000 and January 2019. Preliminary screening was conducted by reading the titles and abstracts to exclude the literature irrelevant to the theme of the paper. According to inclusion and exclusion criteria, 67 literatures were included in the final analysis. RESULTS AND CONCLUSION: Graphene has good biocompatibility, and has low cytotoxicity to prokaryotic cells and eukaryotic cells, but the cytotoxicity can be further reduced by chemical modification or surface modification, so as not to affect the growth of cells. Graphene and its derivatives can promote the growth and chondrogenic differentiation of human bone marrow mesenchymal stem cells, as well as the proliferation and maturation of chondrocytes, and accelerate the repair of cartilage defects. Due to its mechanical strength and electrical conductivity, graphene can compound biomimetic cartilage material, which is suitable for cartilage tissue engineering. Graphene has several unresolved problems and challenges, but the application potential of graphene-related materials may pave the way for future breakthroughs in tissue engineering research.
2.The determination of perphenazine by a new flow-injection chemiluminescence method
Jingfeng YI ; Xiaonian HAN ; Chunling YU ; Yuhai TANG
Journal of Xi'an Jiaotong University(Medical Sciences) 2004;0(05):-
Objective To establish a rapid and precise continuous flow-injection chemiluminescence (CL) method for the determination of perphenazine. Methods In HNO_3 medium, perphenazine could be oxidated by ceriuim (IV) and CL was proportional to the perphenazine concentration without any sensitizers. Thus, a new flow-injection CL method was developed. Results Under the optimized conditions, the proposed method allowed the determination range within 1.0?10~ -7 -7.0?10~ -5 g/mL with the detection limit of 8.0?10~ -8 g/mL. Eleven parallel assays were conducted on perphenazine of 1.0?10~ -6 g/mL, with the relative standard deviation of 1.8%. Conclusion The method is simple, rapid, precise, and sensitive, and has broad linear range; therefore, it has been applied to the the determination of the perphenazine in tablets with satisfactory results.
3.Flow-injection-enhanced chemiluminescence method for the determination of three β-blockers
Lijuan WANG ; Yuhai TANG ; Baoping LI ; Honglang LIU ; Jingfeng YI
Journal of Pharmaceutical Analysis 2010;22(2):91-96
Objective To develop a rapid, simple and sensitive chemiluminescence method for the determination of three β-blockers (bisoprolol, atenolol and propranolol). Methods The chemiluminescence of cerium (Ⅳ)-sulfite system was obviously sensitized by adding anyone of three β-blockers in acid media. A new chemiluminescence method was set up by combining with flow-injection technique and used to determine the three β-blockers. Results Good linear ranges were obtained at the concentrations of 2.0×10-7g/mL-4.0×10-5g/mL, 1.0×10-7g/mL-3.0×10-5g/mL and 7.0×10-7g/mL-1.0×10-5g/mL, respectively, with the detection limits of 5.0×10-8g/mL, 7.0×10-8g/mL and 5.0×10-8g/mL (S/N=3), respectively, and the relative standard deviations for 11 times consecutive injections of 1.0×10-6g/mL bisoprolol, atenolol and propranolol were 3.57%, 2.21% and 2.26%, respectively. Conclusion The developed method is sensitive, accurate, rapid and of low cost. And it can be applied to determine bisoprolol, atenolol and propranolol in pharmaceutical preparations.
4.In vitro susceptibilities of 5 antifungal agents against 52 strains of Penicillium marneffei
Wanshan CHEN ; Xiaoping TANG ; Yecheng LU ; Linghua LI ; Weinan SONG ; Jingfeng CHEN
Chinese Journal of Infectious Diseases 2008;26(3):143-145
Objective To investigate in vitro activities of 5 fungal agents(amphotericin B,ketoconazole,fluconasole,5-fluorocytoaine and itroconazole)against Penicillium marneffei,providing references for clinical treatment.Methods E-test was used to test the in vitro susceptibilities of 5 antifungal agents (amphotericin B,ketoconazole,fluconasole,5-fluorocytoaine and itroconazole)against yeast form and mycelial form of 52 Penicillium marneffei strains isolated from our hospital.Results The 90% minimal inhibitory concentrations(MIC90)of amphotericin B,ketoconazole,fluconasole,5-fluorocytoaine and itroconazole against yeast form of Penicillium marneffei were 0.250,0.160,24.000,4.000,0.006 mg/L,the minimal inhibitory concentration(MIC)ranges were 0.004-0.500,0.002-0.016,1.000-256.000,0.002-32.000 and 0.002-0.008 mg/L,respectively;the MIG90 of the 5 agents against mycelial form of Penicil lium marneffei were 1.500,0.125,256.000,24.000 and 0.012 mg/L,respectively;the MIC ranges were 0.064-4.000,0-006-0.940,1-000-256.000,0.125-32.000 and 0.002-0.064 mg/L respectively.Five antifungal agents had different susceptibility patterns against both forms of Penicillium marneffei.And itroconazole was the most susceptible one,ketoconazole follows as the second.There was significant difference between the MICs of the same agent against yeast form of Penicillium marneffei and mycelial form of Penicillium marneffei.Conclusion In vitro antifungal agents suscepbibility tests of Penicillium marneffei can provide important references information for clinical treatment.
5.Immunomodulatory effects of sea cucumber fucoidan on macrophage and the signaling pathways
Qi ZHANG ; Xuemin LI ; Zhaojie LI ; Tao ZUO ; Qingjuan TANG ; Yaoguang CHANG ; Jingfeng WANG ; Changhu XUE
Chinese Pharmacological Bulletin 2015;(1):87-91,92
Aim To investigate the immunomodulatory effects of sea cucumber fucoidan ( SC-FUC) on macro-phage and the signaling pathways. Methods Cell via-bilities in response to different concentrations of SC-FUC were analyzed by MTT, phagocytosis ability was detected by neutral red,and nitric oxide ( NO) produc-tion was examined by Griess reaction kit. The mRNA expression levels of IL-6 , IL-10 , Toll-like receptors (TLRs) and related signal molecules MyD88, TRIF, NF-κB were assayed by real-time PCR. All the experi-ments were based on murine RAW264. 7 cell line. Re-sults SC-FUC could promote RAW264 . 7 cell prolif-eration, phagocytosis as evidenced by uptake of neutral red and release of NO. The effects were significant at the early stage (6 h and 12 h) . SC-FUC could up-reg-ulate the expression of IL-6 , IL-10 , TLR4 , TLR5 , TLR9. Moreover, mRNA expressions of TLRs signaling molecules were increased, as well as MyD88, TRIF, NF-κB. Conclusions SC-FUC could activate macro-phage, and then promote the immune function by pro-moting production or expression of NO, IL-6, IL-10. It is speculated to be relevant to activated cell surface re-ceptors in macrophage, including TLR4, TLR5, TLR9, and NF-κB signaling pathways.
6.Flow-diverter devices in complex intracranial aneurysm: a complication analysis
Minghao YANG ; Jianxun TANG ; Bao CHEN ; Na LI ; Zhonghui YANG ; Ligang HU ; Jingfeng TANG
Chinese Journal of Neuromedicine 2023;22(11):1129-1135
Objective:To evaluate the complications of complex intracranial aneurysms after intervention with flow-diverter (FD) devices.Methods:Sixty patients with complex intracranial aneurysms accepted FD devices in Department of Cerebrovascular Diseases, Second Affiliated Hospital of Guilin Medical University from July 2018 to June 2021 were chosen. Clinical and imaging data of these patients were retrospectively analyzed, and complications were recorded: procedure-related adverse events, early postprocedural complications, complications during follow-up, and covered branch occlusion.Results:A total of 61 FD devices (47 Pipeline Flex, 10 Tubridge, 4 Surpass Streamline) were implanted in 60 patients. Incidence of procedure-related adverse events was 8.3% (5/60), including 3 with incomplete stent apposition, 1 with intraoperative bleeding, 1 with aneurysm neck not covered by stent; incidence of early postprocedural complications was 6.7% (4/60), including 3 with hemorrhagic complication and 1 with ischemic complication. DSA follow-up ([22.7±16.8] months) was completed in 54 patients; aneurysm healed rate was 83.3% (45/54). First DSA follow-up 6 months after surgery showed that in-stent restenosis was 7.4% (4/54), of which 2 deteriorated to parent vessel occlusion at 2- and 3-year after procedure, respectively. A total of 78 branch arteries were covered by FD devices, and only 1 (1.3%, 1/78) demonstrated branch artery occlusion at last follow-up, without clinical symptoms.Conclusion:The complications of complex intracranial aneurysms after intervention with FD devices should be recognized; incomplete stent apposition is the main procedure-related adverse event, and hemorrhagic complication mainly appear in the early postprocedural period; in-stent restenosis should be vigilant during follow-up.
7.Application prospect of computer vision technology assisted ultrasonography in diagnosis and treatment of liver diseases
Guoxu FANG ; Wenting XIE ; Kaizhi CHEN ; Siqi CHEN ; Minyong CHEN ; Xiangwen LIAO ; Lina TANG ; Jingfeng LIU
Chinese Journal of Digestive Surgery 2023;22(4):462-467
Ultrasound examination has the advantages of non-radiation, non-invasive, low cost and high efficiency, and is the most commonly used method of liver imaging examination. In recent years, the application of computer vision technology to the intelligent analysis of ultrasound images has become a research hotspot in the field of intelligent healthcare. Through large-scale data training, the intelligent analysis model of ultrasound omics based on machine learning algorithm can assist clinical diagnosis and therapy, and improve the efficiency and accuracy of diagnosis. Based on the literature, the authors summarize the application proprect of computer vision technology assisted ultrasonography in the evaluation of diffuse liver lesions, focal liver lesions, microvascular invasion of liver cancer, postoperative recurrence of liver cancer, and postoperative therapy response to trans-catheter arterial chemoembolization.
8.CAS9 is a genome mutator by directly disrupting DNA-PK dependent DNA repair pathway.
Shuxiang XU ; Jinchul KIM ; Qingshuang TANG ; Qu CHEN ; Jingfeng LIU ; Yang XU ; Xuemei FU
Protein & Cell 2020;11(5):352-365
With its high efficiency for site-specific genome editing and easy manipulation, the clustered regularly interspaced short palindromic repeats (CRISPR)/ CRISPR associated protein 9 (CAS9) system has become the most widely used gene editing technology in biomedical research. In addition, significant progress has been made for the clinical development of CRISPR/CAS9 based gene therapies of human diseases, several of which are entering clinical trials. Here we report that CAS9 protein can function as a genome mutator independent of any exogenous guide RNA (gRNA) in human cells, promoting genomic DNA double-stranded break (DSB) damage and genomic instability. CAS9 interacts with the KU86 subunit of the DNA-dependent protein kinase (DNA-PK) complex and disrupts the interaction between KU86 and its kinase subunit, leading to defective DNA-PK-dependent repair of DNA DSB damage via non-homologous end-joining (NHEJ) pathway. XCAS9 is a CAS9 variant with potentially higher fidelity and broader compatibility, and dCAS9 is a CAS9 variant without nuclease activity. We show that XCAS9 and dCAS9 also interact with KU86 and disrupt DNA DSB repair. Considering the critical roles of DNA-PK in maintaining genomic stability and the pleiotropic impact of DNA DSB damage responses on cellular proliferation and survival, our findings caution the interpretation of data involving CRISPR/CAS9-based gene editing and raise serious safety concerns of CRISPR/CAS9 system in clinical application.