2.Inhibitory effect of compound NS5806 on cardiac transient outward potassium channel dependents on interaction between auxiliary subunits
ZHANG HONG-XUE ; ZHANG HUA ; WANG YU-HONG ; XU YAN-FANG
Chinese Journal of Pharmacology and Toxicology 2017;31(10):1027-1028
OBJECTIVE Transient outward potassium current (Ito) plays a crucial role in cardiac phase 1 repolarization and the channels are assembled by pore-forming α-subunits (Kv4.2 or Kv4.3) and auxiliary subunits (KChIP2 and DPP6). Previous studies have found that the compound NS5806 increases Ito in canine ventricular cardiomyocytes through slowing current decay. Here, we reported that NS5806 produced an acute inhibitory action on Ito in mouse ventricular cardiomyocytes and human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CM). METHODS Whole-cell patch-clamp was used to record Ito in native myocytes and in HEK cells expressing cloned Kv4.x/KChIP2/DPP6 channels; Western-blot detected the channel protein expression. RESULTS In isolated mouse ventricular cardiomyocytes, NS5806 (0.1-30 μmol·L-1) inhibited Ito in a concentration-dependent manner with IC50 of 6.6±1.9 μmol·L-1. The current decay was significantly accelerated with a time constant from 53.8±5.5 to 41.8±3.0 ms at +60 mV (P<0.01). Similarly, NS5806 concentration-dependently reduced the Ito peak current amplitude with an acceleration of current decay. In addition, NS5806 increased IKv4.2/KChIP2 and delayed current decay, but decreased IKv4.2/KChIP2/DPP6 with the acceleration of current decay. The inhibitory action on the current was more potent if DPP6 expression level was increased from Kv4.2/KChIP2/DPP61:1:1 to 1:1:3. Western-blot showed a higher expression of DPP6 protein in mouse heart and in hiPS- CM compared to canine heart. Moreover, specific knock- down DPP6 expression by siRNA antagonized the inhibitory action of NS5806 in hiPS-CM. Our results pointed to an important role of DPP6 subunit in the regulation of NS5806 on the channel. By using molecular docking simulation, five interaction sites with high possibility between KChIP2 and DPP6 were identified. Mutations of those sites changed the inhibitory action of NS58056 into excitatory effect on the current with the delay of current decay. CONCLUSION NS5806 significantly inhibits Ito by accelerating current decay in mouse cardiomyocytes and hiPS-CM. The effect depends on the interaction between DPP6 and KChIP2 subunits.
3.Inhibitive effect of 3-bromopyruvic acid on human breast cancer MCF-7 cells involves cell cycle arrest and apoptotic induction.
Xiao-hong LIU ; Xue-fang ZHENG ; Yong-li WANG
Chinese Medical Journal 2009;122(14):1681-1685
BACKGROUNDBreast cancer is one of the most common malignancies in women and is highly resistant to chemotherapy. Due to its high tumour selectivity, 3-bromopyruvic acid (3-BrPA), a well-known inhibitor of energy metabolism has been proposed as a specific anticancer agent. The present study determined the effect of 3-BrPA on proliferation, cell cycle and apoptosis in the human breast cancer MCF-7 cell line and other antitumour mechanisms.
METHODSMCF-7 cells were treated with various concentrations of 3-BrPA for 1 - 4 days, and cell growth was measured by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay. Marked morphological changes in MCF-7 cells after treatment with 3-BrPA were observed using transmission electron microscopy. The distributions of the cell cycle and apoptosis were analyzed by flow cytometry. Immunohistochemistry was used to indicate the changes in the expression of Bcl-2, c-Myc, and mutant p53.
RESULTS3-BrPA (25 microg/ml) significantly inhibited the proliferation of MCF-7 cells in a time-dependent manner. The MCF-7 cells exposed to 3-BrPA showed the typical morphological characteristics of apoptosis, including karyopycnosis, nuclear condensation and oversize cytoplasmic particles. In addition, flow cytometric assay also showed more apoptotic cells after 3-BrPA stimulation. The cells at the G0 and G1 phases were dramatically decreased while cells at the S and G2/M phases were increased in response to 3-BrPA treatment after 48 hours. Furthermore, 3-BrPA stimulation decreased the expressions of Bcl-2, c-Myc and mutant p53, which were strongly associated with the programmed cell death signal transduction pathway.
CONCLUSION3-BrPA inhibits proliferation, induces S phase and G2/M phase arrest, and promotes apoptosis in MCF-7 cells, which processes might be mediated by the downregulation of the expressions of Bcl-2, c-Myc and mutant p53.
Antineoplastic Agents ; chemistry ; pharmacology ; Apoptosis ; drug effects ; Breast Neoplasms ; Cell Cycle ; drug effects ; Cell Division ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Female ; Flow Cytometry ; G2 Phase ; drug effects ; Humans ; Immunohistochemistry ; Molecular Structure ; Pyruvates ; chemistry ; pharmacology ; S Phase ; drug effects
4.Inhibitory effect of N-acetyl-seryl-aspartyl-lysyl-proline on epithelial-mes-enchymal transition by heat-shock protein 27/zinc finger proteins
Haijing DENG ; Shifeng LI ; Lijuan ZHANG ; Xinxin XUE ; Shipu DU ; Yue SUN ; Hong XU ; Fang YANG
Chinese Journal of Pathophysiology 2015;(1):1-7
AIM: To detect whether N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) inhibits epithelial-mes-enchymal transition in A549 cells induced by TGF-β1 through suppressing the expression of heat shock protein 27 (HSP27) and zinc finger proteins Snail (including SNAI1and SNAI2) which ultimately inhibited the deposition of type I and type III collagens.METHODS:The colocalizations of HSP27 and SNAI1/SNAI2 respectively on A549 alveolar epi-thelial cells induced by TGF-β1 were measured by confocal microscopy .The expression of HSP27, SNAI1 and SNAI2 at mRNA level was detected by real-time PCR.Western blotting analysis was used to detect the expression of HSP 27, SNAI1 and SNAI2 on epithelial-mesenchymal transition in A549 cells induced by TGF-β1 and also the deposition of type I and type III collagens in A549 cells transfected with HSP27shRNA prior to TGF-β1 stimulation.RESULTS: Compared with control group, TGF-β1 increased the expression of HSP27, SNAI1, SNAI2, type I and type III collagen, which decreased significantly followed by Ac-SDKP intervention.The expression of SNAI1, type I and type III collagen decreased signifi-cantly after transfected with HSP27shRNA in A549 cells, which had the similar effect on Ac-SDKP intervention.CON-CLUSION:Ac-SDKP inhibits the transition of cultured A 549 cells to myofibroblasts and attenuates collagen synthesis by suppressing the expression of HSP 27 and zinc finger proteins SNAI 1 and SNAI2.
5.Development of spatiotemporal frequency turning in rat lateral geniculate neuron
Xu-hong, ZUO ; Xue-feng, SHI ; Fang, XIE ; Li-min, XU ; Kan-xing, ZHAO
Chinese Journal of Experimental Ophthalmology 2012;30(5):388-391
BackgroundRecent researches suggested that properties of neurons in the lateral geniculate neuron (LGN) may represent an important neural limitation on the development of basic spatial and temporal vision,and even binocular rivalry.However,previous studies on the properties of spatiotemporal frequency tuning of LGN were rather concentrated on a monkey or cat,whereas little is known about rat.ObjectiveThis study was to examine the development of spatiotemporal frequency tuning in rats LGN.MethodsTwenty Wistar rats were collected and divided into 14-16 day,20-22 day,27-30 day and 60 day groups according to the different ages after their eyes opened and 5 rats were assigned for each group.Extracellular single neuron recording was carried out in the rats to study the spatio-temporal receptive field properties of neurons in LGN by sinusoidal gratings visual stimuli.Dynamic changes of the spatio-temporal receptive field properties of neurons in LGN with the development of Wistar rats were evaluated.ResultsThe differences between band-pass and low-pass distribution of temporal frequency or spatial frequency of rat LGN were not statistically significant (x2 =0.68,0.47,P>0.05 ).The optimal temporal frequency of receptive field in rat LGN went up to the maximum value until 60 day in Wistar rats.The mean optimal temporal frequencies of neurons in the four different age groups were ( 2.5 ± 1.3 ),( 2.6± 1.2),(2.6± 1.1 ) and ( 3.6± 1.1 ) Hz with significant differences among the 4 groups (F=4.53,P<0.05 ),and those in the 14-16 day group,20-22 day group,27- 30 day group were significantly lower than in the 60 days group ( q =4.43,4.10,4.03,P < 0.05 ).No significant differences were seen among the 14-16 day group,20-22 day group and 27-30 day group ( P>0.05 ).The optimal spatial frequency values in the four groups were ( 0.04 ± 0.04 ),( 0.04 ± 0.03 ),( 0.05 ± 0.03 ),( 0.05 ± 0.04 ) cpd,respectively without statistical difference among them ( F =0.58,P > 0.05 ).The temporal and spatial bandwidth values in the various age groups were not statistically significant among the four groups ( F =0.37,1.22,P>0.05). Conclusions The development of temporal and spatial frequency characteristics of the rat LGN receptive field may be related to its functional visual pathway.
6.Clinical Analysis of Serratia Infections in 4 Newborn Infants
hui-xin, WANG ; jian-ping, HE ; xue-fang, YANG ; hong, LIU
Journal of Applied Clinical Pediatrics 1986;0(02):-
Objective To analyze the clinical characteristic and prognosis of Serratia infections in newborn infants and increase awareness of Serratia infections.Methods The clinical manifestations,diagnosis,complications,treatment and prognosis of Serratia infections were analyzed in 4 hospitalized newborn infants in neonatology center from Jul.2008 to Feb.2009.Results Among the 4 cases,blood culture revealed Serratia marcescens in 3 cases(1 case was preterm infant),cerebral spinal fluid culture revealed Serratia liquefacien in the fourth case.The main clinical manifestations were fever,convulsion and poor response,WBC and CRP were much higher,while obvious thrombocytopenia was only found in the preterm infant.Two cases of septicemia infection alone recovered after the treatment of the third-generation cephalosporin for at least 2 weeks,while the other 2 cases of septicemia infection combined with purulent meningitis,included 1 case of preterm infant and 1 case of Serratia liquefacien infection,developed meningoencephalitis and brain abscess confirmed by serial imaging,both of which had poor neurological sequelaes.Conclusions As a opportunistic pathogen,Serratia can cause severe infection in newborns.The patients complicated with meningitis should be followed up and pay more attention to the high incidence of neurological sequelaes.
7.Investigation of Tilt Angle of Head-Up Tilt Test on Children
yu-li, WANG ; feng-wen, ZHANG ; xue-ying, LI ; jun-bao, DU ; hong-fang, JIN
Journal of Applied Clinical Pediatrics 2006;0(13):-
0.05).The different tilt angles impacted patients' fear psychology(?2=8.038,P=0.018).The order of the extent of children's fear psychology represented from low to high at the angle of 60?,70? and 80?,respectively.The extent of the children's fear psychology had positive correlation with the tilt angle(r=0.669,P=0.002).Conclusions The tilt test angle does not affect the positive rate of HUTT and the hemodynamics in children undergoing HUTT with angles from 60? to 80?.The children at the tilt angle 60? had less fear than at the angle of 70? or 80?.The 60? tilt angle of HUTT in children is recommended in the clinical practice.
8.Single cell four-plex nested fluorescent PCR for hemophilia A genetic diagnosis and gender determination
Yi FANG ; Xiao-Wei LU ; Xue-Feng WANG ; Yun FENG ; Hong-Li WANG ;
Chinese Journal of Laboratory Medicine 2003;0(09):-
Objective To develop a rapid and efficient single cell PCR method for the non-invasive prenatal hemophilia A genetic diagnosis.Methods Six STR markers (DXS15,DXS9901,G6PD, DXS1073,DXS1108 and F8Civsl3) closely linked to F Ⅷ gene were examined in 118 healthy individuals and 12 hemophilia A families by muhi-plex fluorescent PCR.Three markers with the higher heterozygote rate and diagnostic rate were chosen and combined with amelogenin gene to establish the four-plex nested fluorescent PCR on single lymphocyte level.Results The single lymphocyte amplification rates of Amelogenin,DXS15,FSCivsl3 and DXSI073 were 94.3%,91.4%,100% and 100% in the normal male,and 100% ,97.1% ,97.1% and 97.1% in the normal female's respectively.The female was heterozygous in DXS1073 and DXS15.However,no allele dropout was found in both markers.Neither the false negative nor the false positive amplification was observed.Conclusion The single cell four-plex nested fluorescent PCR method established in this study is convenient and efficient,and will be hopefully employed in the clinical non-invasive prenatal genetic diagnosis for hemophilia A.
9.Application and optimization of field psychological emergency rescue chest
Bao-Guo YU ; Hong-Fang XUE ; Xue-Xian SHAN ; Yi-Fei FANG ; Song BAI
Chinese Medical Equipment Journal 2018;39(4):76-78
Objective To optimize the design of the field psychological emergency rescue chest.Methods The deficiencies of the chest were summarized during the drilling and actual application of the psychological rescue unit,and some optimization countermeasures were put forward accordingly.Results The chest was optimized from the aspects of selection of chest body, internal and external layout as well as equipped devices.Conclusion The optimized chest can better meet the needs of the disaster emergency rescue.
10.Proteomic analysis of Helicobacter pylori in human gastritis and gastric cancer.
Yun-hui YOU ; Xue-gong FANG ; Ping LIU ; Hong-bo LIU ; Xue-fei TIAN ; Xue-mei YAN
Journal of Central South University(Medical Sciences) 2008;33(5):384-390
OBJECTIVE:
To establish 2-dimensional electrophoresis (2-DE) maps of Helicobac-ter pylori in human gastritis, and gastric cancer, to identify the differentially expressed proteins,and to discuss the role of bacterial factor in pathogenesis.
METHODS:
The total proteins of Helicobacter pylori in human gastritis and gastric cancer were separated by immobilized pH gradient-based 2-DE. The differentially expressed proteins were screened by PDQuest analysis software and identified by peptide mass fingerprint based on matrix-assisted laser desorption/ionization time of flight mass spectrometry, and searched on database.
RESULTS:
A well-resolved and reproducible 2-DE pattern of Helicobacter pylori was obtained from patients with human gastritis and gastric cancer. Fourteen differentially expressed proteins were identified, including proteins related to anti-oxidation,molecular chape-rones and detoxification, enzymes related to metabolism,proteins related to cytoarchitecture,and proteins related to signal conduction.
CONCLUSION
A well-resolved and reproducible 2-DE pattern of Helicobacter pylori in human gastritis and gastric cancer is established and differentially expressed proteins from these 2 diseases are identified. The differentiation of protein expression may play an important role in the pathogenesis of gastric cancer.
Bacterial Proteins
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analysis
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Electrophoresis, Gel, Two-Dimensional
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Female
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Gastritis
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microbiology
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Helicobacter Infections
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microbiology
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Helicobacter pylori
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Humans
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Male
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Proteome
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analysis
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Proteomics
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methods
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Stomach Neoplasms
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microbiology