1.Preparation and biocompatibility of panax notoginseng saponins-hydroxyapatite/chitosan scaffold
Shuxiang CHEN ; Le KANG ; Wenhuan OU ; Tujian SI ; Linjian DING
Chinese Journal of Tissue Engineering Research 2013;(34):6116-6122
BACKGROUND:Panax notoginseng saponins promotes bone repair by improving vascular proliferation. Therefore, the scaffolds carrying panax notoginseng saponins were supposed to be used to improve bone repair at the bone defect region. However, the biocompatibility of scaffolds remains unclear.
OBJECTIVE:To evaluate the biocompatibility of panax notoginseng saponins-hydroxyapatite/chitosan scaffolds.
METHODS:A new bone repair scaffold has been generated by thoroughly mixtures of 0, 0.1, 1, 10 mg panax notoginseng saponins and chitosan/hydroxyapatite using in-situ composite technique and freeze-drying technique. Morphology and mechanical property of the scaffold were observed under a scanning electron microscope. (1) Cel proliferation test:rabbit bone marrow mesenchymal stem cel s of passage 3 were cultured in four kinds of drug loaded hydroxyapatite/chitosan composite material leaching liquor. Cel s normal y cultured were considered as controls. 3-(4, 5-Dimethylthiazol-2-yl) 2, 5-diphenyl tetrazolium bromide was used to measure absorbance value of cel s in each group. (2) Hemolysis test:Rabbit anticoagulated blood was added with four kinds of drug loaded hydroxyapatite/chitosan composite material leaching liquor. Absorbance values were measured using a microplate reader in each group. (3) Pyrogen test:The four kinds of drug loaded hydroxyapatite/chitosan composite material leaching liquor and saline were respectively injected into ear vein of rabbits, and the increase of rabbit body temperature was detected.
RESULTS AND CONCLUSION:Drug loaded hydroxyapatite/chitosan composite material contained three dimensional porous structure of 110μm in diameter. Drug loading process of panax notoginseng saponins did not significantly affect the porosity, pore size and density of the composite material, but decreased its breaking strength and elastic modulus. The larger amount of drug loading showed a more obvious effect. Simple hydroxyapatite/chitosan composite material had good cel ular compatibility. The composite material after drug loading obviously suppressed cel proliferation, and the larger amount of drug loading showed a more obvious effect. The composite material had good blood compatibility before and after drug loading. The composite material had good pyrogen effects before and after drug loading, but accorded with acceptable quality level of pyrogen test.
2.Aspirin inhibits tumor cell metastasis mediated by HGF/c-Met
Xiao-yang DAI ; Si-kang CHEN ; Jin-xin CHE
Acta Pharmaceutica Sinica 2022;57(10):2985-2994
In this study, we investigated the effect of aspirin on tumor biological effects mediated by hepatocyte growth factor/cellular-mesenchymal-epithelial transition factor (HGF/c-Met) axis, and preliminarily explored the molecular mechanism of inhibiting tumor metastasis by aspirin. The binding of aspirin to c-Met was predicted by molecular docking; cellular thermal shift assay (CETSA) was used to verify the binding of aspirin to c-Met at the cellular level. The inhibitory effect of aspirin on c-Met kinase was detected by kinase activity; Western blot, cell scattering test, cell branching morphogenesis and Transwell test were used to evaluate the cell signal transduction, morphological changes and migration and invasion ability. The results showed that aspirin could effectively inhibit the kinase activity of c-Met with a half inhibitory concentration of 0.95 mmol·L-1. The results of docking showed that aspirin could bind to the ATP pocket of c-Met protein, and the main binding sites were Tyr1230, Tyr1159 and Met1229. The CETSA test also showed that aspirin could form binding complex with c-Met protein. Western blot results showed that aspirin could inhibit the up-regulation of phosphorylated Met stimulated by HGF in a concentration-dependent manner. The results of cell scattering test showed that aspirin could block HGF/c-Met promoted cell scattering in a concentration dependent manner. Aspirin could almost completely block the biological function mediated by c-Met activation at the concentration of 4 mmol·L-1, and this effect was independent of HGF. Similarly, the results of MDCK cell branching morphogenesis experiment showed that aspirin could inhibit HGF/c-Met mediated invasive growth in a concentration dependent manner. The results of Transwell test showed that aspirin could block HGF/c-Met mediated cell migration and invasion in a concentration-dependent manner. Aspirin could almost completely block the biological function mediated by c-Met activation at the concentration of 4 mmol·L-1, and this effect was independent of HGF. The above results indicate that aspirin can bind to c-Met, thereby blocking the biological effects mediated by HGF/c-Met, and inhibiting tumor metastasis. This study revealed the new biological function of aspirin, and provided a new theoretical basis for a comprehensive understanding of the anti-metastatic effect of aspirin.
3.Loss of expression of wtKLF6 in hepatocellular carcinoma and its effect on hepatocellular carcinoma cell proliferation
Shaoping WANG ; Lili KANG ; Xiaoping CHEN ; Hejun ZHOU ; Yujun SUI ; Wenzhang SI
Chinese Journal of Hepatobiliary Surgery 2011;17(2):132-137
Objective To investigate the expression and genetic alterations of KLF6 in hepatocellular carcinoma (HCC) and explore their functional mechanisms in the oncogenesis and development of HCC. Methods Real-time quantitative-PCR, direct sequencing and LOH approaches were used to detect KLF6 genetic abnormalities in HCC. The experiment had 2 groups, an experimental group and a control group. In the experimental group, the transfected plasmid pcDNA3.0 was recombined with KLF6 and tranfected into HCC HepG2 cells. MTT, flow cytometry and Western blotting were used to observe the effect of anti-oncogene wild type KLF6 on HepG2 cells by transgenic method for 48 h.Results Expression levels of KLF6 were significantly downregulated in HCCs(P<0. 01), as detected by qRT-PCR. LOH occurred in 11 (52%) of the 21 tumors, and all the samples with LOH showed KLF6 down-regulation. The mutational frequency was 29%, and sequence changes located in activation domain of KLF6. Meanwhile, MTT assay showed a significant antiproliferative effect of the transfected wtKLF6 on HepG2 cells(42.7%, P<0.05). Fluorescence-activated cell sorting analysis revealed that KLF6 induced apoptosis. Conclusion The deregulation of KLF6 together with genetic abnormalities of allelic imbalance and mutations may play an important role in HCC pathogenesis.
4.Identification of the mutation of SOD1 gene in a familial amyotrophic lateral sclerosis.
Shu-gui SHI ; Lu-si LI ; Kang-nin CHEN ; Xing LIU
Chinese Journal of Medical Genetics 2004;21(2):149-152
OBJECTIVETo identify the mutation of Cu/Zn superoxide dismutase(SOD1) gene in an amyotrophic lateral sclerosis (ALS) family with unique phenotype.
METHODSFive exons of SOD1 gene were amplified by PCR. The differences of these products were analyzed by PCR-single strand conformation polymorphism and visualized by silver staining.
RESULTSAbnormal bands were found in exons 2 and 5 of SOD1 gene in several familial members. DNA sequence analysis verified that a base pair insertion occurred in the codon area of exon 2 and in the intron area of exon 5. And the insertion mutation of exon 2 led to a frameshift mutation and premature stop. It is a new type of SOD1 mutation which may be associated with familial amyotrophic lateral sclerosis.
CONCLUSIONInsertion mutation of exon 2 may be responsible for the disease of an ALS family in Chongqing.
Adult ; Amyotrophic Lateral Sclerosis ; genetics ; Humans ; Mutation ; Polymorphism, Single-Stranded Conformational ; Superoxide Dismutase ; genetics ; Superoxide Dismutase-1
5.Application of circular dichroism to the study of interactions between small molecular compounds and DNA.
Zhen-jia LIU ; Yi-kang SI ; Xiao-guang CHEN
Acta Pharmaceutica Sinica 2010;45(12):1478-1484
Circular dichroism (CD) is an useful technique for monitoring DNA conformation changes resulting from changes in environmental conditions, such as temperature, ionic strength, and pH, and also for the study of the interaction between DNA and ligands (including small molecules and proteins). CD spectroscopy of DNA arises from the asymmetric backbone sugars and by the helical structures often adopted by nucleic acids. By the interpretation of induced circular dichroism (ICD) of ligand signals resulting from the coupling of electric transition moments of the ligand, DNA bases within the asymmetric DNA environment, ligand-DNA interactions, as well as the DNA-binding mode can be assessed. A number of important conclusions have been reported that related to the observed ICD signals resulting from the interactions between intercalators and groove binders with DNA. If short oligonucleotide sequences are used in the study, sequences-specific of binding also can be deduced. CD determination requires smaller amounts of sample, and not limited by the molecular weight or size and can be performed rapidly; though CD is of low resolution, but it's a complement to NMR and X-ray diffraction methods. This review will introduce the characters of the CD spectra of DNA, and its application to the studies of DNA with small molecules; some progress of the studies in our laboratory will also be discussed. CD is expected to be used as a screening method in seeking more DNA-targeted drugs, such as, antineoplastic, antimicrobial and antiviral drugs.
Animals
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chemistry
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Base Sequence
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Circular Dichroism
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methods
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DNA
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chemistry
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metabolism
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Humans
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Intercalating Agents
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chemistry
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Protein Binding
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Small Molecule Libraries
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pharmacology
6.Balloon kyphoplasty for osteoporotic vertebral compression fractures with osteonecrosis.
Gen-lin WANG ; Hui-lin YANG ; Wei-min JIANG ; Liang CHEN ; Bin MENG ; Xin MEI ; Kang-wu CHEN ; Tian-si TANG
Chinese Journal of Surgery 2010;48(8):593-596
OBJECTIVETo explore the clinical efficacy of the percutaneous balloon kyphoplasty for osteoporotic vertebral compression fractures with osteonecrosis.
METHODSThe clinical data of 31 patients with osteoporotic vertebral compression fractures associated with osteonecrosis from January 2005 to January 2008 were analyzed retrospectively. There were 13 male and 18 female in this study. The mean age of the patients was 71 years (range from 57 to 84 years). The back pain lasted for 4.2 months (from 1 month to 10 years). Radiography, MRI and CT examination were performed. The patients were treated by percutaneous balloon kyphoplasty and the vertebral body tissue was extracted to perform common pathological examination. The anterior vertebral height was measured on a standing lateral radiograph before operation, after operation (one day after operation) and at the final follow-up. A Visual Analog Scale (VAS) and the Oswestry Disability Index (ODI) were chosen to evaluate pain status and functional activity.
RESULTSThe mean follow-up was for 27 months (range, 18 to 48 months). The anterior vertebral body height of fracture vertebra was restored from (34.7 +/- 3.1)% preoperatively to (71.4 +/- 2.3)% postoperatively, and to (70.2 +/- 2.5)% at the final follow-up. There was a significant improvement between preoperative and postoperative values (P < 0.05) and no difference between postoperatively and at the final follow-up (P > 0.05). The VAS was 8.7 +/- 0.4 preoperatively, 2.3 +/- 0.7 postoperatively, and 1.9 +/- 0.2 at the final follow-up; and the ODI was 89.1 +/- 2.7 preoperatively, 31.7 +/- 3.1 postoperatively, and 29.1 +/- 2.7 at the final follow-up. There was statistically significant increment in the VAS and ODI postoperatively compared with preoperatively (P < 0.05), while there was no statistically significant differences between postoperatively and at the final follow-up (P > 0.05). There was a significant increment between preoperative and final follow-up values (P < 0.05). Asymptomatic cement leakage occurred in two cases. New vertebral fracture occurred in one case.
CONCLUSIONBalloon kyphoplasty is a safe and effective procedure for osteoporotic vertebral compression fractures with osteonecrosis.
Aged ; Aged, 80 and over ; Female ; Follow-Up Studies ; Fractures, Compression ; complications ; etiology ; Humans ; Kyphoplasty ; methods ; Male ; Middle Aged ; Osteonecrosis ; etiology ; surgery ; Osteoporosis ; complications ; Retrospective Studies ; Spinal Fractures ; complications ; etiology ; Vertebroplasty
7.Surgery for lesions involved the carotid artery
Jingcheng GU ; Yanping XU ; Zhongyi SI ; Jinhui SUI ; Xuefeng WANG ; Weiwei XING ; Jian KANG ; Ying CUI ; Xuyun SUN ; Li CHAI ; Dong CHEN ; Rui WANG ; Yongxin LIU ; Liang GONG ; Xiaofeng MA ; Luzan CHEN ; Feifei GUO
Chinese Archives of Otolaryngology-Head and Neck Surgery 2006;0(09):-
OBJECTIVE To investigate the surgical methods for the lesions involved the common carotid artery.METHODS The clinical data of 11 cases with lesions involved the common carotid artery who underwent operations were retrospectively studied.The lesions were 1 case with recurrence tumor after 3/4 partial laryngectomy,1 case with bleeding of the carotid aneurysm caused by tuberculosis,1 case with iatrogenic carotid aneurysm,3 cases with carotid body tumor,1 case with thyroid gland cancer,2 cases with neck tumor,1 case with injury of the carotid artery and 1 case with gas gangrene.RESULTS Common carotid artery was reconstructed in 2 cases after removal of the tumors.The tumors were resected using the carotid shunt in 2 cases.Common carotid artery was sutured in 1 case with neck injury.The common carotid artery was repaired in 1 case with iatrogenic carotid aneurysm after removal of the tumor.The carotid artery was dissected out from the thyroid gland cancer in 1 case.The common carotid artery was reserved in 2 cases after resection of the neck tumors. Neck drainage was performed in the case with gas gangrene.CONCLUSION The surgical methods for lesions involved the carotid artery after removal of the tumors include the reconstruction of the carotid artery, resection and suture the carotid artery,and free of the carotid artery from the tumors.
8.Alterations of NK cell frequency and function in HIV/HCV co-infected patients
Xin ZHANG ; Peng ZHAO ; Fu-Biao KANG ; Xin-Wei ZHANG ; Chan SI ; Xue-Li CHEN ; Wei-Wei CHEN ; Min ZHAO
Chinese Journal of Experimental and Clinical Virology 2011;25(4):248-250
Objective To study the impacts of HIV/HCV co-infection to NK cells by investigating the changes of frequencies and functions of NK cells in HIV/HCV co-infected patients. Methods Frequencies and counts of NK cells were measured in patients with HIV mono-infection, HCV monoinfection, HIV/HCV co-infection and health control (HC) group by flow cytometer ( FCM ). After stimulated with PMA and K562 cells, PBMCs were examined the proportion of IFN-γ+ NK cells by FCM. Proportion of killed K562 cells were detected to analyze the killing functions of NK cells. Results The frequencies of NK cells, the percentages of IFN-γ+ NK cells as well as the functions of NK cells killing the K562 cells in HIV/ HCV co-infection, HIV mono-infection and HCV mono-infection groups were all lower than those of HC group significantly, the absolute counts and killing functions of NK cells in co-infection group were significantly lower than those of HIV or HCV mono-infection group. Conclusions The counts and functions of NK cells were affected more in HIV/HCV co-infections than those in HIV or HCV mono-infection.
9.Epidemic characteristics and viral antibody level among healthy people of Japanese B encephalitis in Henan province in 2010.
Xiao-yan TANG ; Kai KANG ; Si-yuan SHANG ; Chao XU ; Xing-le LI ; Hong-xia MA ; Hao-min CHEN ; Bian-li XU
Chinese Journal of Preventive Medicine 2012;46(10):888-891
OBJECTIVETo understand the epidemic characteristics and viral antibody level among healthy people of Japanese B encephalitis (JE) in Henan province in 2010.
METHODSA total of 433 selected JE cases in Henan province in 2010 were analyzed by descriptive epidemiological method. Xinyang and Luoyang were selected as survey sites in 2010.12 administrative villages were randomly selected from both cities. As the investigation objects, 519 healthy people from the two cities were randomly selected by eight age groups:less than one year old, 1 - 2 years old, 3 - 4 years old, 5 - 6 years old, 7 - 14 years old, 15 - 19 years old, 20 - 59 years old, and above 60 years old. A total of 1008 samples of blood specimens were collected both in May and November, and JE viral antibody was detected by micro-cytopathic effect neutralization test.
RESULTSThe incidence rate of JE was 0.46/100 000 (433/94 130 434) in Henan province in 2010.97.69% (423/433) of the patients were found between July and September, and 81.06% (351/433) were distributed in Nanyang, Xinyang, Luoyang, Zhumadian and Zhoukou city. Children aged 0 to 14 years were the primarily affected group (82.22%, 356/433), the people above 15 years old accounted for 17.78% (77/433) of whole cases in Henan province, but the same group accounted for 65.79% (50/76) of whole cases in Luoyang city, which obviously higher than the percentage in Henan province (χ(2) = 79.57, P < 0.05). Most patients were scattered children in Henan province, accounting for 58.89% (255/433). In Luoyang city, most patients were peasants, accounting for 44.74% (34/76). The antibody positive rate of JE among health people above 15 years old in Luoyang city was 48.94% (46/94), which was lower than it in Xinyang city at 97.78% (88/90). The difference showed statistical significance (χ(2) = 55.42, P < 0.05). The antibody positive rate among healthy people under vaccination was 50.41% (61/121), which was obviously higher than that among people without vaccination, at 16.67% (6/36) in Luoyang city. The difference showed statistical significance (χ(2) = 12.92, P < 0.05). The antibody positive rate among healthy people under vaccination was 67.11% (51/76) in Xinyang city, which was obviously higher than that among people without vaccination, at 46.39% (45/97). The difference showed statistical significance (χ(2) = 7.40, P < 0.05).
CONCLUSIONThe incidence of JE showed seasonal and regional characteristics, there were differences among ages and occupations. The difference was consistent with the difference in viral antibody level among health people in Henan province and Luoyang city.
Adolescent ; Adult ; Antibodies, Viral ; blood ; Case-Control Studies ; Child ; Child, Preschool ; China ; epidemiology ; Encephalitis Virus, Japanese ; immunology ; Encephalitis, Japanese ; blood ; epidemiology ; immunology ; Humans ; Incidence ; Infant ; Middle Aged ; Young Adult
10.Effect of soy isoflavones on cAMP/PKA pathway in breast cancer cells of the rat..
Cheng-Zhao LIN ; Hai-Tian MA ; Si-Xiang ZOU ; Guo-Jie WANG ; Wei-Hua CHEN ; Zheng-Kang HAN
Acta Physiologica Sinica 2005;57(4):517-522
Soy isoflavones have been reported to be natural chemopreventive in several types of human cancer. Daidzein and genistein are two main components of soy isoflavones. In our previous study, they were shown to be anti-proliferative and induce cell cycle arrest at S phase of SHZ-88 rat breast cancer cells. We hypothesized that soy isoflavones might exert its anticancer effect by activating cAMP/PKA pathway. The present study was designed to analyze the effect of soy isoflavones on the cAMP/PKA pathway in SHZ-88 cells. Daidzein and genistein were dissolved in DMSO. Cells were treated with 50 mug/ml daidzein and 15 mug/ml genistein, respectively, and with only equal DMSO in the culture medium as control. The cellular cAMP content was tested by radioimmunoassay (RIA). The activity of adenylate cyclase (AC), phosphodiesterase (PDE) and PKA were measured by RIA and (gamma-(32)P) ATP incorporation. Reverse transcript-polymerase chain reaction (RT-PCR) was used to analyze the expression of cAMP response element binding protein (CREB) mRNA of the cells. The results showed that the concentration of cAMP in the cells treated with 50 mug/ml daidzein and 15 mug/ml genistein was significantly increased by 9.5%and 11.0%, respectively, 5 min later (P<0.05), then increased by 31.0%and 40.3%, respectively, 10 min later (P<0.01), compared with that of the control group cells. The activity of AC was not affected during the course of experiment, but that of PDE was decreased to 71.8%and 71.6%, respectively, in the control group 5 min later (P<0.05). The PKA activity was increased to 125.8%and 122.3%, respectively, in the control group 20 min after the cells were treated with daidzein and genistein (P<0.05), and kept at high level till 40 min after treatment. CREB mRNA of the cells treated with daidzein and genistein was increased by 31.6%and 51.1%, respectively, 3 h later (P<0.05), then began to decrease 6 h after treatment. The current study suggests that soy isoflavones activate the cAMP/PKA pathway in SHZ-88 rat breast cancer cells by inhibiting the activity of phosphodiesterase.