2.Effects of overexpression of beta2-adrenoceptor on contraction in cardiac myocytes isolated from failure hearts of rats.
Hong SUN ; Ai-min CHANG ; Yang ZHANG ; Xin-wei JIANG
Chinese Journal of Applied Physiology 2007;23(4):410-414
AIMTo investigate the role of overexpression of beta2-adrenoceptor on contraction in cardiac myocytes isolated from failure hearts of rats and primarily analyses its mechanisms.
METHODSPrimarily cultured cardiac myocytes were infected with adenovirus containing the sequence for human beta2-adrenoceptors. The expression of beta2-adrenoceptors was tested by Western blot. The contraction amplitudes induced by isoprenaline stimulation were measured.
RESULTSOverexpression of beta2-adrenoceptor increased the content in failure cardiac myocytes. The contraction amplitudes in failure cardiac myocytes were lower than that in the control (P < 0.01). Overexpression of beta2 adrenoceptor improved the contraction of failure cardiac myocytes (P < 0.01, Failure+ Adv.Beta2 group vs. Failure group). Selective beta2-adrenoceptor antagonist ICI 118,551 partially reversed the effects (P < 0.05, Failure+ Adv.beta2 + ICI group vs Failure + Adv.beta2 group), but the contraction amplitudes in this Failure +/- Adv.beta2 + ICI 118,551 group were still higher than that in only heart failure group (P < 0.05). Selective beta1 adrenoceptor antagonist CGP20712A completely inhibited the effects of overexpression of beta2 adrenoceptor on contraction amplitude in failure cardiac myocytes.
CONCLUSIONOverexpression of beta2-adrenoceptors improves the contraction of cardiac myocytes isolated from failure hearts of rats. The effect is related to beta1-adrenoceptor.
Adenoviridae ; genetics ; Adrenergic beta-Antagonists ; pharmacology ; Animals ; Cells, Cultured ; Heart Failure ; metabolism ; physiopathology ; Humans ; Imidazoles ; pharmacology ; Isoproterenol ; pharmacology ; Male ; Myocardial Contraction ; Myocytes, Cardiac ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptors, Adrenergic, beta-2 ; genetics ; metabolism
3.Changes of local field potentials in M1 underlying the specific behavior in rat.
Yiliang ZHAO ; Jiantao SUN ; Yongji SONG ; Fang LI ; Hongbin AI ; Min WANG
Journal of Biomedical Engineering 2012;29(4):634-649
The local field potentials (LFPs) underlying specific behavior were recorded and analyzed in this paper from primary motor cortex (M1) with several medium, such as the self-made single channel micro-electrodes, the system of multi-channels physiological signal acquisition and processing and so on. During the experiment, the specific behavior was divided into four periods according to the changes of the recorded LFPs and the changes of the specific behavior recorded simultaneously in rats. The four periods were named prophase of catching period, planning period, catching period and the completion period, respectively. Then several methods were used for the analysis of the LFPs by MATLAB, such as time domain analysis, power spectral distribution analysis and time-frequency analysis. The results suggested that the LFPs which were caused by different behavior from a large number of movement-related neurons of M1 during the specific behavior in the process of catching play an important part in the "code" guiding role in rats. The results demonstrat that the LFPs of M1 may provide a feasibility to discriminate the motor behavior of forelimb.
Animals
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Brain-Computer Interfaces
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Electrodes, Implanted
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Evoked Potentials, Motor
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physiology
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Feeding Behavior
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physiology
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Male
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Microelectrodes
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Motor Cortex
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physiology
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Rats
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Rats, Wistar
4.Maternal deprivation-induced stress responses in female rats.
Bo SUN ; Shang-feng GAO ; Ling-juan RUAN ; Ai-min BAO
Journal of Zhejiang University. Medical sciences 2012;41(2):125-131
OBJECTIVETo investigate the effect of maternal deprivation on the activity of hypothalamo-pituitary-adrenal (HPA) axis, acute stress response and the sex hormone receptors expression in hypothalamic paraventricular nucleus (PVN) in female rats.
METHODSMaternal deprivation model was induced in female Sprague-Dawley (SD) rats. Foot shock was given at different stages of estrus cycle during the adulthood. Plasma estradiol, testosterone and adrenocorticotropin (ACTH) levels were determined by radioimmunoassay; and plasma corticosterone level was measured by enzyme linked immunosorbent assay. The expression of androgen receptor (AR) and estrogen receptor (ER-β) in the hypothalamic PVN was detected by immunohistochemistry.
RESULTSDecreased plasma ACTH and corticosterone levels were found in the proestrus of female rats with maternal deprivation (P=0.012 and P=0.019, respectively). A significant down-regulation (P=0.008) of PVN-AR, but not PVN-ER-β expression was found in female rats with maternal deprivation.
CONCLUSIONMaternal deprivation may reduce the HPA axis activity in female SD rats, which is closely correlated with the fluctuation of the circulating sex hormones. The androgen in the hypothalamus seems to play a more important role than the estrogen in this procedure.
Adrenocorticotropic Hormone ; blood ; Animals ; Corticosterone ; blood ; Estradiol ; blood ; Female ; Hypothalamo-Hypophyseal System ; physiopathology ; Maternal Deprivation ; Paraventricular Hypothalamic Nucleus ; metabolism ; Pituitary-Adrenal System ; physiopathology ; Rats ; Rats, Sprague-Dawley ; Receptors, Androgen ; metabolism ; Receptors, Estrogen ; metabolism ; Stress, Physiological ; Testosterone ; blood
5.Lentivirus-mediated RNA interference suppresses APRIL expression and enhances chemosensitivity in colorectal cancer cells.
Jing GUAN ; Ai-min SUN ; Li-hui WANG ; Mei-rong HE
Journal of Southern Medical University 2011;31(9):1600-1604
OBJECTIVETo investigate the effects of lentivirus-mediated RNA interference (RNAi) targeting a proliferation-inducing ligand (APRIL) on the chemosensitivity to 5-FU of colorectal cancer cell line LoVo.
METHODSThe lentiviral vector siRNA-APRIL was constructed and verified by PCR and DNA sequencing. LoVo cells were transfected with siRNA-APRIL plasmid, non-targeting siRNA plasmid, or empty plasmid. Forty-eight hours after the transfection, the cells were examined for APRIL expression using Western blot. Seventy-two hours after treatment with 10 µg/ml 5-FU, flow cytometry was used to detect the cell apoptosis and cell cycle changes. The cell growth inhibition rate following 5-FU exposure was detected by MTT assay.
RESULTSPCR analysis and DNA sequencing demonstrated that the RNAi sequence targeting APRIL gene was successfully inserted into the lentiviral vector. siRNA-APRIL transfection resulted in obviously reduced expression of APRIL in LoVo cells. After 5-FU exposure, the apoptosis rate of siRNA-APRIL-transfected cells were increased to (21.12∓3.35)%, significantly higher than that in cells transfected with the non-targeting plasmid or the empty plasmid [(13.06∓1.92)% and (12.28∓1.79)%, respectively, P<0.01]; the cell number in G0/G1 phase increased while that in G2/M phase decreased in siRNA-APRIL-transfected cells. The growth inhibition rate in siRNA-APRIL group was (59.67∓5.03)%, significantly higher than that in the other two groups [(42.33∓4.16)% and (39.67∓4.73)%, respectively, P<0.01].
CONCLUSIONLentivirus-mediated RNAi targeting APRIL can effectively suppress the expression of APRIL in LoVo cells and enhance the chemosensitivity of the cells to 5-FU.
Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Colorectal Neoplasms ; drug therapy ; metabolism ; pathology ; Drug Resistance, Neoplasm ; Fluorouracil ; pharmacology ; Humans ; Lentivirus ; genetics ; RNA Interference ; Tumor Necrosis Factor Ligand Superfamily Member 13 ; genetics ; metabolism
6.Synthesis and bioactivity of N- 4- ( benzimidazole-2-thio) phenyl -N'-alkyl guanidine derivatives.
Yun-gen XU ; Ai-min XING ; Min HONG ; Xiao-yu SUN
Acta Pharmaceutica Sinica 2007;42(2):152-156
In order to get some novel compounds with potent iNOS inhibitory activity, 12 target compounds of N-[ 4-( benzimidazole-2-thio) phenyl ] -N'-alkyl guanidine derivatives ( I1- I12 ) were synthesized from 1-benzoyl-3-[ 4-( benzimidazole-2-thio) phenyl] thioureas (4) by hydrolysis with 2. 0 mol x L(-1) sodium hydroxide solution containing tetrahydrofuran to form the corresponding N-[ 4-(benzimidazole-2-thio) phenyl] thioureas (5) which was S-ethylated with ethyl iodide, followed by amination with primary amines or secondary amines. The intermediate 4 was synthesized from 2-mercaptobenzimidazole (1) by reaction with 1-chloro-4-nitrobenzene to form 2-( 4-nitrophenylthio) benzimidazole (2) which was reduced by iron powder and hydrochloric acid, followed by reaction with benzoyl isothiocyanate. The structures of compounds I1 - I12 were confirmed by IR, MS,1H NMR and elemental analysis. The results of preliminary pharmacological test showed that the activities of three compounds (I 1, I8 and I10) were stronger than aminoguanidine, especially for compound I1.
Animals
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Benzimidazoles
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chemical synthesis
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chemistry
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pharmacology
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Cells, Cultured
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Dose-Response Relationship, Drug
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Enzyme Inhibitors
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chemical synthesis
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chemistry
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pharmacology
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Guanidines
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chemical synthesis
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chemistry
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pharmacology
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Macrophages, Peritoneal
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cytology
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drug effects
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enzymology
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Mice
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Molecular Structure
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Nitric Oxide Synthase Type II
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antagonists & inhibitors
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metabolism
7.Rna interference of annexin II gene in PC3 cells by using small interference RNA synthesized with in vitro transcription.
Ya-Wei YUAN ; Ai-Min SUN ; Ying LUI ; Long-Hua CHEN ; A G BANERJEE
Chinese Medical Sciences Journal 2007;22(1):33-37
OBJECTIVETo silence annexin II gene expression by using small interference RNA (siRNA) in prostate cancer cell line PC3.
METHODSFor in vitro transcription, four sequences of 29-nucleotide DNA template oligonucleotides were designed, and one pair of the sequences were complementary to annexin II gene. The other pair was negative control. The 8 nucleotides at the 3' end of each oligonucleotide were complementary to the T7 Promoter Primer. The sense and antisense siRNA templates were transcribed by T7 RNA polymerase and the resulting RNA transcripts were hybridized to create dsRNA. The siRNA was transfected into prostate cancer cell PC3. For assaying the efficiency of siRNA, confocal microscopy, Northern blotting, and Western blotting were employed to examine the expression of annexin II protein and its mRNA. 3H thymidine was used to measure DNA synthesis.
RESULTSThe siRNA sequence specific to annexin II gene was capable of inhibiting the expression of annexin II protein and its mRNA. And cellular DNA synthesis was significantly reduced in siRNA transfected cells.
CONCLUSIONSThe protocol for the synthesis of siRNA by T7 RNA polymerase is feasible. Annexin II might be involved in DNA synthesis.
Annexin A2 ; genetics ; Cell Line, Tumor ; DNA Replication ; DNA, Neoplasm ; genetics ; Humans ; Male ; Promoter Regions, Genetic ; genetics ; Prostatic Neoplasms ; genetics ; RNA Interference ; RNA, Neoplasm ; genetics ; RNA, Small Interfering ; genetics ; Transcription, Genetic
8.Effects of sustained-release alpha-lipoic acid tablet on blood lipid, blood sugar and insulin in hyperlipidemic New Zealand rabbits.
Xie-sheng CHEN ; Hong LIU ; Ai-min JI ; Yue-lian YANG ; Yu-fa YAO ; Liang SUN ; Ou CHE
Journal of Southern Medical University 2009;29(4):704-706
OBJECTIVETo evaluate the effect of sustained-release alpha-lipoic acid tablets (SRLA) on blood lipid, glucose and insulin levels in hyperlipidemic New Zealand rabbits.
METHODSTwenty-four New Zealand rabbits were randomized into normal diet group, high-fat diet group, and high-fat diet + SRLA (300 mg/tablet) group with corresponding feed. At the beginning and 4 weeks after the feeding, the serum levels of total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), blood glucose, and serum insulin were measured, and insulin sensitivity index (ISI) was calculated.
RESULTSFour weeks after feeding with high-fat diet, the insulin levels was elevated and the ISI lowered in the New Zealand rabbits, indicating successful establishment of the animal model of hyperlipidemia. Compared with the high-fat diet group, the serum levels of TG, TC, LDL-C and insulin were significantly reduced (P<0.05), and the ISI was significantly increased (P<0.05) in high fat diet + SRLA group. But no statistically significant difference was found in the blood glucose among the 3 groups.
CONCLUSIONSRLA can significantly correct blood lipid and insulin disorders in hyperlipidemic New Zealand rabbits and prevent the occurrence of insulin resistance and hyperlipidemia.
Animals ; Blood Glucose ; metabolism ; Delayed-Action Preparations ; Hyperlipidemias ; blood ; drug therapy ; metabolism ; Insulin ; metabolism ; Lipids ; blood ; Male ; Rabbits ; Tablets ; Thioctic Acid ; administration & dosage ; pharmacology ; therapeutic use
9.p35 and p25 expressions and Cdk5 kinase activity in primary cultured rat hippocampal neurons with X-ray exposure.
Yong-Qing HAN ; Ai-Min SUN ; Que-Ling LIU ; Long-Hua CHEN ; Ya-Wei YUAN
Journal of Southern Medical University 2009;29(3):405-407
OBJECTIVETo study the expressions of p35 and p25 and Cdk5 kinase activity in cultured rats hippocampal neurons following X-ray exposure to provide experimental evidence for prevention and treatment of radiation encephalopathy.
METHODSThe hippocampal neurons cultured for 12 days were subjected to a single-dose X-ray exposure of 30 Gy. Western blotting was used to detect the p35 and p25 protein levels, and the effect of pretreatment with roscovitine, a Cdk5 inhibitor, on the apoptosis of the hippocampal neurons following the exposure was examined with 4',6-diamidino-2-phenylindole (DAPI) staining.
RESULTSThe protein level of p35 increased significantly 3.5 and 4 h after the irradiation by 1.51-/+0.13 and 1.45-/+0.14 folds in comparison with the control level, respectively (P<0.01), and the p25 level increased significantly 6 h after irradiation by 1.62-/+0.28 folds (P<0.05). Nuclear condensation occurred in (24.8-/+3.97)% of the neurons 24 h after 30 Gy X-ray exposure, a rate significantly higher than that in the nonexposed cells [(1.82-/+1.08)%, P<0.01) and that in roscovitine-pretreated neurons [(7.74-/+2.27)%, P<0.01).
CONCLUSIONX-ray exposure activates Cdk5 by increasing the p35 and p25 expressions in rat hippocampal neurons, and inhibition of Cdk5 activity with roscovitine can significantly protect the neurons from apoptosis.
Animals ; Animals, Newborn ; Cells, Cultured ; Cyclin-Dependent Kinase 5 ; genetics ; metabolism ; Female ; Hippocampus ; cytology ; metabolism ; radiation effects ; Male ; Neurons ; cytology ; metabolism ; radiation effects ; Phosphotransferases ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley
10.Preparation of SO4(2-)/TiO2-La2O3 solid superacid and its catalytic activities in acetalation and ketalation.
Shui-jin YANG ; Ai-min BAI ; Ju-tang SUN
Journal of Zhejiang University. Science. B 2006;7(7):553-558
SO(4)(2-)/TiO(2)-La(2)O(3), a novel solid superacid, was prepared and its catalytic activities at different synthetic conditions are discussed with esterification of n-butanoic acid and n-butyl alcohol as probing reaction. The optimum conditions have also been found, mole ratio of n(La(3+)):n(Ti(4+)) is 1:34, the soaked consistency of H(2)SO(4) is 0.8 mol/L, the soaked time of H(2)SO(4) is 24 h, the calcining temperature is 480 degrees C, the calcining time is 3 h. Then it was applied in the catalytic synthesis of ten important ketals and acetals as catalyst and revealed high catalytic activity. Under these conditions on which the molar ratio of aldehyde/ketone to glycol is 1:1.5, the mass ratio of the catalyst used in the reactants is 0.5%, and the reaction time is 1.0 h, the yields of ketals and acetals can reach 41.4%-95.8%.
Acetylation
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Acids
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chemistry
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Catalysis
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Hydrogen-Ion Concentration
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Ketones
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chemistry
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Lanthanum
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chemistry
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Oxides
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chemistry
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Powders
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Sulfates
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chemistry
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Titanium
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chemistry