1.Adrenomedullin promotes cell-cell contact formation of podocytes through regulating Rho GTPases
Chuan XIAO ; Nan DONG ; Zhonghua ZHAO ; Xueguang LIU
Chinese Journal of Nephrology 2016;32(4):284-291
Objective To investigate the regulatory effect of adrenomedullin (AM) on the cell-cell contact formation of podocytes and the possible mechanism.Methods Podocytes were treated with AM (10-7 mol/L),AM combined with a PKA inhibitor H89 (10-4 mol/L),and forskolin (10-5 mol/L) as positive control respectively for 12 hours.Immunofluorescent staining was applied to observe the distribution of cell adhesion molecules and actin-associated proteins.Western blotting assay was used to assess their protein levels.Rho GTPases activity was analyzed by GST-pull down assay and their protein levels were tested by Western blotting.Results AM induced the redistribution of adhesion molecules,actin-associated proteins as well as the F-actin at cell-cell contacts between podocytes.This effect was similar to that of forskolin and could be blocked by H89.The levels of those proteins did not change significantly (P > 0.05).AM up-regulated the activities of RhoA,Rac1 and Cdc42 (P < 0.05),which were partially blocked by H89.The protein levels of Rho GTPases showed no difference compared with the control (P > 0.05).Conclusions AM may promote cell-cell contact formation of podocytes,probably through enhancing the activity of Rho GTPases and then resulting in the redistribution of adhesion molecules,actin-associated proteins and F-actin,which is partially mediated through cAMP-PKA signaling pathway.
2.Effects of Glycosaminoglycan From Scallop Skirt on The Expression of Vascular Endothelial Growth Factor During The U937 Foam Cell Formation
Fu-Sheng SUN ; Sai LIU ; Chuan-Xia JU ; Nan YU
Progress in Modern Biomedicine 2007;7(6):846-848
Objective: To study the effects of glycosaminoglycan from scallop skirt (SS-GAG) on the expression of vascular endothelial growth factor (VEGF) and the mechanism of anti-atherosclerosis action of SS-GAG. Methods: U937 cells were incubated with 80mg/L oxidized low density lipoprotein (ox-LDL) for 48h to establish a macrophage-derived foam cell model. In addition, U937 cells were divided into 6 groups: ①control group; ②ox-LDL group; ③ox-LDL+200mg/L SS-GAG group; ④ox-LDL+400 mg/L SS-GAG group; ⑤ox-LDL+800 mg/L SS-GAG group; ⑥ox-LDL +Heparin 100 mg/L group.After 48h's incubation, the concentration of VEGF in the medium was determined by ELISA. Results: The expression of VEGF in U937 foam cells was obviously higher than that of the control group. After treatment with heparin (100 mg/L) and SS-GAG of different concentrations (200mg/L, 400 mg/L, 800 mg/L), the expression of VEGF decreased obviously, especially in the ox-LDL+800 mg/L SS-GAG group (P<0.01). Conclusion: The antiatherogenic effect of SS-GAG is probably due to its ability to inhibit VEGF expression.
3.Recent advances in small-molecule inhibitors targeting influenza virus RNA-dependent RNA polymerase
Hui-nan JIA ; Rui-fang JIA ; Ji-wei ZHANG ; Yuan-min JIANG ; Chuan-feng LIU ; Ying ZHANG ; Xin-yong LIU ; Peng ZHAN
Acta Pharmaceutica Sinica 2024;59(1):43-60
Influenza virus causes serious threat to human life and health. Due to the inherent high variability of influenza virus, clinically resistant mutant strains of currently approved anti-influenza virus drugs have emerged. Therefore, it is urgent to develop antiviral drugs with new targets or mechanisms of action. RNA-dependent RNA polymerase is directly responsible for viral RNA transcription and replication, and plays key roles in the viral life cycle, which is considered an important target of anti-influenza drug design. From the point of view of medicinal chemistry, this review summarizes current advances in diverse small-molecule inhibitors targeting influenza virus RNA-dependent RNA polymerase, hoping to provide valuable reference for development of novel antiviral drugs.
4.Effects of PTK787 on cell proliferation and expression of fak mRNA in K562.
Xiao-Hua DI ; Ri-Ling CHEN ; Xiao-Li LIU ; Chuan TIAN ; Ya-Nan GUO
Journal of Experimental Hematology 2010;18(3):597-600
The aim of this study was to investigate the effects of tyrosine kinase inhibitor PTK787 on cell proliferation, cell cycle and the expression of fak mRNA of human chronic myeloid leukemia (CML) cell line K562, and to explore the mechanism of PTK787 against acute myeloid leukemia. The MTT method was used to detect the effects of PTK787 in various concentrations and at different time points on proliferation of K562 cells; the flow cytometry was used to determine the effects of PTK787 in different concentrations on cell cycle of K562 cells; the RT-PCR was used to assay the expression of fak mRNA in K562 cells treated with PTK787 for 48 hours. The results showed that along with increasing of the concentration and prolonging of time, the inhibitory rate of PTK787 on K562 proliferation was gradually enhanced. The comparison between various concentration groups at same time or comparison between various time groups in same concentration showed significant differences (p < 0.05), in which the effect of 320 micromol/L PTK787 on cells was strongest, while the continuous increase of PTK787 concentration or prolong of action time did not enhance the inhibitory rate on K562 proliferation. With increasing of drug concentration, the cell proportion in G(1) phase gradually increased, the cell proportion in S phase gradually decreased, the comparison between various groups revealed significant differences (p < 0.05), however the continuous increase of drug concentration from 160 micromol/L did not obviously change the cell proportion in phases of cell cycle. With increasing of drug concentration, the expression of fak mRNA in K562 cells gradually reduced with significant differences between various groups (p < 0.05), but with continuous increase of drug concentration from 160 micromol/L, the effect of PTK787 on the expression of fak mRNA in K562 cells also did not obviously change. It is concluded that the PTK787 shows effect of anti-leukemia cells through inhibiting transformation of the K562 cells from G(1) phase into S phase and decreasing the expression of fak mRNA in cells.
Cell Cycle
;
Cell Proliferation
;
drug effects
;
Focal Adhesion Kinase 1
;
genetics
;
Gene Expression Regulation, Leukemic
;
Humans
;
K562 Cells
;
Phthalazines
;
pharmacology
;
Pyridines
;
pharmacology
;
RNA, Messenger
;
genetics
5.Influenza surveillance and antigenic and genetic characterization of predominant strains in Wuhan area in 2003.
Hong-hao ZHU ; Xi-yan XU ; Chuan-nan LIU ; Xin-ming LIN ; Dun-jin ZHOU ; Jin-song PENG
Chinese Journal of Experimental and Clinical Virology 2004;18(3):210-212
OBJECTIVETo study influenza epidemic and analyze antigenic and genetic characterization of the predominant strains in Wuhan area in 2003.
METHODSEpidemiological data and specimens from influenza patients were collected from surveillance sites weekly. Viruses were isolated from the specimens. Three H3 isolates were chosen to do antigenic analysis by hemagglutination inhibition (HI) test and their HA1 region was sequenced.
RESULTSTotally 58 influenza viruses were isolated from 418 specimens, 57 of them were identified as H3 subtype and 1 of them was B subtype; both monthly positive rate and numbers of influenza like illness had two peaks of winter and summer, the highest peak appeared in July. The 3 new H3 isolates were antigenically different from vaccine strain A/Panama/2007/99, 14 amino acid changes have been found in HA1 domain of these 3 strains compared with A/Panama/2007/99, phylogenetic analysis also confirmed the difference in HA1 domain.
CONCLUSIONSInfluenza epidemic had two peaks in Wuhan area in 2003. The activity of H3 virus was strengthened remarkably. And they are antigenically and genetically different from the vaccine strain.
Amino Acid Sequence ; Antigens, Viral ; immunology ; China ; epidemiology ; Genes, Viral ; Glycosylation ; Hemagglutination Inhibition Tests ; Humans ; Influenza A Virus, H3N2 Subtype ; genetics ; immunology ; isolation & purification ; Influenza, Human ; epidemiology ; virology ; Molecular Sequence Data ; Phylogeny ; Sequence Analysis, Protein
6.Determination of Molecular Weight and Content of Bletilla striata Polysaccharide by HPSEC-ELSD
Chuan WANG ; Yan ZHANG ; Nan LI ; Yali LI ; Jiangyun LIU ; Peilie CAI ; Lili HAO
China Pharmacy 2018;29(9):1198-1201
OBJECTIVE:To set up a method for determination of molecular weight and content of polysaccharide in Bletilla striata. METHODS:HPSEC-ELSD method was adopted. The determination was performed on TSK-GEL G4000 PWXL column with mobile phase consisted of pure water at the flow rate of 0.6 mL/min.The column temperature was 30 ℃,and sample size was 20 μL. Evaporative light scattering detector was used.The molecular weight and content of polysaccharide in 3 batches of B. striata were established. RESULTS:The linear range of weight average molecular weight of B. striata polysaccharide were 24.17-178.00 kD(R2=0.985 5). The linear range of BT07 content determination were 0.508 0-5.080 mg/mL(R2=0.998 4). The limits of detection and quantitation were 0.116 5 and 0.274 0 mg/mL. RSDs of precision,stability and reproducibility tests were all lower than 2%(n=6 or n=7).Average recoveries rate were 99.16%-100.20%(RSD=0.39%-0.64%,n=9).Average retention time of 3 batches of samples was 14.28 min(RSD=4.35%,n=3),and weight average molecular weight was 23.54 kD(RSD=3.78%, n=3). Polydispersity coefficient D,MW/Mn)ranged 1.463-1.578. Average content of sample was 93.4%(RSD=4.22%,n=3). CONCLUSIONS:HPSEC-ELSD method is simple,rapid,accurate and reliable,which can be used for simultaneous determination of B.striata polysaccharide.
7.Effect of general anesthesia guided by electroencephalography monitoring on postoperative delirium in elderly patients with non-acute fragile brain function
Caiyi ZHAO ; Xin LIU ; Zhao LI ; Na SHI ; Nan ZHAO ; Feifei LIU ; Chuan WU ; Xiuli WANG
Chinese Journal of Anesthesiology 2021;41(6):651-655
Objective:To evaluate the effect of general anesthesia guided by electroencephalography (EEG) monitoring on postoperative delirium (POD) in elderly patients with non-acute fragile brain function.Methods:Sixty patients of both sexes with non-acute fragile brain function, aged 65-85 yr, of American Society of Anesthesiologists physical status Ⅱ or Ⅲ, with body mass index of 18-30 kg/m 2, undergoing hip replacement, were divided into 2 groups ( n=30 each) by a random number table method: conventional general anesthesia group (group C) and general anesthesia guided by EEG monitoring group (group E). Anesthesia was maintained by intravenous infusion of propofol 50-150 μg·kg -1·min -1 and remifentanil 0.05-0.30 μg·kg -1·min -1 and intermittent intravenous boluses of rocuronium.In group E, the dose of anesthetic was reduced when the EEG burst-suppression ratio≥10% for more than 1 min or anesthesia index (AI) <40.If the situation mentioned above still existed after 1 min, the dose of anesthetic was continued to be reduced or norepinephrine was injected intravenously.In group C, the amount of intraoperative anesthesia was adjusted according to the changes in hemodynamics.Norepinephrine 4-10 μg or dopamine 1 mg was given intravenously in the light of the patients′ heart rates when intraoperative hypotension occurred.At 10 min after anesthesia induction, immediately after skin incision, immediately at the end of surgery and at 1 h after surgery, blood samples were obtained from the artery and jugular venous bulb for blood gas analysis and for calculation of jugular bulb blood oxygen content (CjvO 2), artery-jugular bulb blood oxygen content difference (Ca-jvO 2), cerebral oxygen uptake rate (CERO 2) and jugular-arterial blood lactate concentration difference (Djv-aLac). The emergence time, amounts of intraoperative anesthetics, use of noradrenaline, cumulative time of EEG burst inhibition and duration of AI<40 were recorded.The development of POD was assessed within 5 days after surgery by the confusion assessment method for the intensive care unit and the duration was recorded. Results:Compared with group C, recovery time, cumulative time of EEG burst inhibition and duration of AI<40 were significantly shortened, the intraoperative consumption of propofol and remifentanil was decreased, the requirement for intraoperative noradrenaline was increased, CjvO 2 was increased, Ca-jvO 2 and CERO 2 were decreased immediately at the end of surgery and at 1 h after surgery, the incidence of POD within 5 days after surgery was decreased, and POD duration was shortened in group E ( P<0.05). Conclusion:General anesthesia guided by EEG monitoring can reduce the development of POD in elderly patients with non-acute fragile brain function.
8.Fluoride preconditioning attenuates sensitivity induced by tooth bleaching: a scanning electron microscopy study.
Li-feng PAN ; Man-jing DENG ; Lu-chuan LIU ; Nan LI ; Na LIU ; Guo-dong ZHANG
West China Journal of Stomatology 2007;25(3):230-232
OBJECTIVETo evaluate the effects of fluorid on morphology change in enamel and dentin during tooth bleaching.
METHODSThe study population consisted of twelve patients who required the extraction of first premolars for orthodontic reasons. Twelve participants were divided into three groups: bleaching with NaF-treated group, bleaching-treated group and control group. Immediately after bleaching treatment, all teeth were extracted and prepared for scanning electron microscope (SEM). Morphologic observations were carried out with SEM.
RESULTSIn the bleaching-treated group, mild demineralization was observed on the surface of enamel and collapse of collagen scaffold was also observed on the longitudinal section of dentine. The diameter of dentinal tubule was not uniform due to peritubular dentine was demineralized. In the bleaching with NaF-treated group, the demineralization of enamel and dentin were reduced and some diameter of dentinal tubule were smaller than bleaching-treated group.
CONCLUSIONFluoride can reduced the demineralization of enamel and dentine obviously, which may be applied as a therapeutic tool for sensitivity induced by tooth bleaching.
Dental Enamel ; Dentin ; Fluorides ; Humans ; Microscopy, Electron, Scanning ; Phosphates ; Tooth Bleaching
9.An experimental study on the prevention and treatment of postburn intestinal injury and bacterial translocation by Sijunzi decoction in scalded rats.
Li GUO ; Nan-Ding DONG ; Ai-Bing XIONG ; Zheng-Yu LIU ; Cheng-Rong LIU ; Xiao-Chuan HE
Chinese Journal of Burns 2003;19(2):89-93
OBJECTIVETo explore the effects of traditional Chinese herbal medicine Sijunzi decoction on amelioration of postburn intestinal injury in scalded rats.
METHODSOne hundred and eighty Wistar rats were randomly divided into 3 groups, i.e. scald and treatment (T), scald control (S) and normal control (C) groups. The rats in T group were gavaged with the decoction consisting of tangshen, tuckahoe, large head atractylodes rhizome, glycyrrhizic and rhubarb in a dose of 2 ml twice daily, while the rats in C group were just gavaged with the same amount of distilled water. The rats were sacrificed according to the scheduled postburn observation timepoints. The contents of TNF, NO, MDA and ATPase activity in rat plasma and the intestinal mucosa and the S-IgA content in the intestinal mucus were determined respectively. The changes in histopathology of intestinal mucosa were observed. The samples from internal organ tissue and blood were obtained for bacterial culture.
RESULTSThe contents of TNF, NO and MDA in the intestinal mucosa tissue and the rat plasma in scalded rats were lowered significantly by Sijunzi decoction. Furthermore, S-IgA secretion from intestinal mucous cells was maintained by Sijunzi decoction. T cell count was recovered and intestinal mucous barrier injury were lessened, and the bacterial positive rate in the internal organs was decreased.
CONCLUSIONTraditional Chinese herbal medicine Sijunzi decoction might be helpful in alleviation of postburn intestinal injury and in the prevention of intestinal bacterial translocation.
Animals ; Bacterial Translocation ; drug effects ; Burns ; blood ; drug therapy ; Drugs, Chinese Herbal ; therapeutic use ; Female ; Intestinal Mucosa ; metabolism ; pathology ; Intestines ; microbiology ; Male ; Rats ; Rats, Wistar
10.Comparison of Regional Cerebral Oxygen Saturation During Cardiac Surgery in Children With Ventricular Septal Defect and Tetralogy of Fallot
Ding HAN ; Ya-Guang LIU ; Chuan OUYANG ; Xiao-Nan WANG ; Shou-Dong PAN ; Yi LUO ; Jia LI
Chinese Circulation Journal 2018;33(10):1016-1020
Objectives: To compare regional cerebral tissue oxygen saturation (rScO2) changes during cardiac surgery in children with ventricular septal defect (VSD) and tetralogy of Fallot (TOF). Methods: A total of 60 children aged 3~36 months were enrolled (28 in VSD group 32 in TOF group). rScO2was monitored by Fore-Sight near-infrared spectroscopy device. rScO2, pulse oxygen saturation (SpO2), systolic pressure, diastolic pressure, heart rate, stroke volume index, cardiac index, systemic vascular reststance index the maximal slope of systolic upstroke (dp/dt max) were obtained at following time points: after anesthesia induction (t0), pericardium opening (t1), 5 min after cardiopulmonary bypass (CPB) initiation (t2), 5 min before separation from CPB (t3), separation from CPB (t4), post-modified ultrafiltration (t5), end of surgery (t6). Results: (1) The lowest rScO2value was observed at separation from CPB (t4), and which was significantly lower than that at t0(P<0.05) for both groups; rScO2, stoke volume index, cardiac index, and dp/dt max at t5were significantly higher than at t4(all P<0.001) for both groups. (2) rScO2and SpO2were significantly higher at t5and t6than at t0(both P<0.05) in TOF group. rScO2at t0-t2was significantly lower in TOF group than in VSD group (both P<0.05). rScO2increased more significantly after modified ultrafiltration and rScO2was positively correlated with SpO2at t0and t1(r=0.35, P<0.05 and r=0.64,P<0.01) in TOF group. (3) In the total cohort, rScO2was positively correlated with age, weight at t0, t1, t3, t4, t5, t6(all P<0.01). After modified ultrafiltration, the increase in cardiac index was positively correlated with increase in rScO2(r=0.41, P<0.05), and the amount of cardiac index and rScO2increases were negatively correlated with age (r=-0.30;r=-0.34, both P<0.05). Conclusions: rScO2is closely related with age and weight. Cerebral oxygen delivery before biventricular surgical correction is lower in TOF group than in VSD group, and the cerebral oxygenation improves significantly after surgical repair. Modified ultrafiltration could significantly improve systemic hemodynamics and rScO2, and TOF children and younger children benefit more from modified ultrafiltration. Pre- and post-separation from CPB period is vulnerable to cerebral desaturation, it is therefore of importance to maintain the cerebral oxygen delivery-consumption balance at these periods for children with TOF and VSD undergoing surgical repair.