1.Senescence or Tumor:The Dual Role of Activated-oncogene Induction
Progress in Biochemistry and Biophysics 2006;0(12):-
The activation of oncogenes occured in most tumors,and is believed to play an important role in tumorigenesis. However,the activation of oncogenes could induce cellular senescence in wild type cells,known as oncogene-induced senescence (OIS). Thus,the activation of oncogenes has the dual role in inducing cellular senescence or tumorigenesis. DNA damage checkpoint response (DDR) is the molecular signal transduction pathway that delay or arrest cell cycle progression in response to DNA damage and is an important molecular mechanism that induce cellular senescence. Activation of oncogenes could produce DNA damage signals and initiate DDR,which subsequently induce cellular senescence. However,when DDR pathway is deficient,activation of oncogenes could induce unlimited DNA hyper-replication and cellular hyper-proliferation,which results in accumulation of genome instability,and tumorigenesis ultimately. Therefore,the dual role of activated oncogenes is regulated by the integrity of DDR pathway. The key role of DDR in regulating activated oncogenes indicates that maintain or restore the integrity of DDR pathway might provide a new strategy in cancer prevention and therapy.
2.SITE-DIRECTED MUTAGENESIS OF TSR1 GENE IN YEAST YARROWIA LIPOLYTICA
Microbiology 1992;0(05):-
The TSR1(thermosensitive rescued)gene associated with the secretion of proteins of the yeast Yarrowia lipolytica was site-directed mutagenesis,restricted and spliced to obtain a series of deletion mutants.These mutants would be useful for studing the function of different domains of TSR1 gene in yeast Yarrowia lipolytica
3.Mechanism of angiostatin induced reduction of vascular leakage in retina and iris of rats with retinopathy of prematurity
Jing, SIMA ; Jian-Xing, MA ; Jiang, GUO ; Si-Si, LUO ; Hao-Jiang, YANG
International Eye Science 2008;8(12):3264-3368
·AIM: To study the effect of an intravitreal injection of angiostatin on vascular leakage in the retina and iris of oxygen-induced retinopathy of prematurity (ROP).·METHODS: Brown Norway rats at postnatal day 7 (P7) were exposed to hyperoxia (750mL/L O2 )for 5 days (P7-12) and then returned to normoxia to induce retinopathy. Angiostatin was reconstituted in sterile Phosphate Buffered Saline(PBS) and diluted to desired different concentrations. Angiostatin solution was injected into the vitreous of the right eye of the ROP rats at P14 and the age-matched normal rats through pars plana using a glass capillary, and the left eye received the same volume of sterile PBS as the control. Vascular permeability was quantified at 1, 2 and 3 days after the injection by measuring albumin leakage from blood vessels into the retina and iris using the Evans blue method and normalized by total protein concentrations. The expression of vascular endothelial growth factor (VEGF) in retina was evaluated using the Western Blot analysis and immuno-histochemistry 24 hours following the injection.·RESULTS: ROP rats showed significant increases of vascular permeability in the retina and iris (P<0.01). Angio-statin reduces vascular permeability in a dose-dependent manner in the retina of ROP rats. The reduction showed a time course trend. [Angiostatin injection reduced retinal vascular permeability by approximately 1.5 and 2-fold at P15 (P<0.05) and P16 (P<0.01), respectively.] Angiostatin injection significantly reduced VEGF levels in the retina of ROP rats but did not affect retinal VEGF levels in normal rats.·CONCLUSION: Angiostatin significantly decreases pa-thological vascular permeability in the retina and iris of ROP rats but not in normal rats. Angiostatin down-regulates VEGF expression in retina of ROP rats. These results suggest that angiostatin may have a therapeutic potential in the treatment of ROP and other diseases with vascular leakage.
4.Changes in calcium ion across plasma membrane by insulin related to the proliferation of human hepatocellular carcinoma
Haiwei ZHANG ; Yingru LUO ; Peie ZHENG ; Xiaoling CHEN ; Turu SI
Chinese Journal of Pathophysiology 2000;0(07):-
AIM: To examine the effect of insulin on the proliferation of human hepatocellular carcinoma cell and its possible mechanisms. METHODS: The human hepatocellular carcinoma cell line(HepG-2) was used to study the changes in calcium ion across plasma membrane (Ca 2+ APM)under the action of insulin by the assay of atomic absorption spectrum, and in the proliferation under the action of insulin and calcium ion antagonist (isoptin). RESULTS: The influx of Ca 2+ APM and the proliferation was increased after insulin administration, but the proliferation was inhibited by isoptin. CONCLUSION: Changes in the homeostasis of calcium ion across plasma membrane was involved in the effect of insulin on the proliferation of human hepatocellular carcinoma.
5.Establishment of migraine rheumatism stasis syndrome animal model.
Hui CHEN ; Gang LUO ; Xue BAI ; Si-jin YANG
China Journal of Chinese Materia Medica 2015;40(22):4452-4455
OBJECTIVETo establish the migraine rheumatism stasis syndrome animal model.
METHODThe rat migraine rheumatism stasis syndrome animal model was established through rheumatism stimulation with manual climate box, 5-HT reduction caused by reserpine and local cerebral vasospasm. General vital signs (activity, weight, eye gum, hair, feeding, excrement), head scratch frequency and image collection were observed to analyze the changes in biological signs of stasis syndrome (tongue image RGB), thrombin and serotonin of model rats.
RESULTThe reserpine group and the reserpine plus rheumatism model group showed significant reduction in blood coagulation time, pain threshold and 5-HT content in blood and brain (P < 0.01); the reserpine plus rheumatism model group showed an increase in eye gum and decreases in activity, feeding, with thin sloppy stool. According to the tough RGB values, the control group showed light red toughs, the reserpine group showed dark purple toughs, the reserpine plus rheumatism model group showed gray toughs, with notable differences in tough RGB values in all three group.
CONCLUSIONThe rheumatism stimulation with manual climate box, 5-HT reduction caused by reserpine and local cerebral vasospasm can be used to induce the migraine rheumatism stasis syndrome animal model, but its modeling assessment method and process shall be further improved.
Animals ; Blood Circulation ; Diagnosis, Differential ; Disease Models, Animal ; Female ; Humans ; Male ; Medicine, Chinese Traditional ; Migraine Disorders ; diagnosis ; physiopathology ; Rats ; Rats, Sprague-Dawley ; Rheumatic Diseases ; diagnosis ; physiopathology
6.In Vivo Kinetics and Biodistribution of a Hantaan Virus DNA Vaccine after Intramuscular Injection in Mice
Si WANG ; Qing NIE ; Lanyan ZHENG ; Jun HU ; Enjie LUO
Virologica Sinica 2010;25(3):177-182
To study the kinetics in vivo of a Hantaan virus DNA vaccine, we constructed a fusion DNA vaccine,pEGFP/S, by cloning the S segment of Hantavirus into the vector, pEGFP-C1, which encodes Green fluorescent protein EGFP. In this report, we provide evidence that pEGFP/S was distributed and persistently expressed for more than 60 days in several organs after inoculation. Our findings suggest that the persistent immune responses induced by a Hantaan virus DNA vaccine are likely due to the plasmid pEGFP/S deposited in vivo, which acts as a booster immunization.
7.Mechanism of Antimicrobial Peptide Resistance
Fu CHEN ; Yu-Ping LUO ; Xi GONG ; Si-Guang LI ;
Microbiology 2008;0(11):-
Antimicrobial peptides are a class of small peptides with anti-extrogenous pathogen activities.They are derived from organism and possess antibacterial,antifungus,antiviruses and anticancer cell actions.In recent years,it’s found that some microbial pathogens are able to resist antimicrobial peptides.The constitutive and inducible mechanism of a pathogen resists a given peptide were reviewed in this paper.
8.Surveillance on endemic situation of schistosomiasis in national surveillance sites of Chongqing City in 2006
Chengguo WU ; Xingjian LUO ; Xin ZHOU ; Bangzhong XIAO ; Zhengyun SI
Chinese Journal of Schistosomiasis Control 1989;0(01):-
Objective To understand the correlative factors of impacting schistosomiasis prevalence so as to provide the scientific evidence for drawing up the control project in Three Gorges Reservoir areas.Methods The report system of schistosomiasis was set up,and the cases were investigated.The population were screened by indirect haemagglutination test(IHA),and the serum-positive people were examined with Kato-Katz technique.The livestock and plants imported from the schistosomiasis endemic areas were investigated.Results Eighty-eight floating people returning from schistosomiasis endemic areas and 107 floating persons from endemic areas were investigated,and the serum positive rates were 1.14% and 1.87%,respectively.No schistosome eggs were found in stool examinations.There was no livestock and plant imported from schistosomiasis endemic areas.The production of local inhabitants depended on mainly cattle,and the river water contact was popular.Conclusions There are infection resources of schistosomiasis imported from endemic areas,which has a potential risk of schistosomiasis prevalence.
9.Effects of N-acetylcysteine on behavior and monoamine neurotransmitters in rats with chronic unpredictable stress
Guoshuai LUO ; Jianli YANG ; Jijian SI ; Lili WANG ; Chengzhan WANG
Tianjin Medical Journal 2016;44(9):1084-1087,1088
Objective To investigate effects of N-acetylcysteine (NAC) on changes of the behavior and the monoamine neurotransmitters in prefrontal cortex (PFC), striatum (ST), amygdala (AM) and hippocampus (HIP) in rat model of chronic unpredictable stress (CUS), and to explore the possible mechanisms related to the NAC. Methods Thirty-two male Sprague-Dawle (SD) rats were divided into CUS group, fluoxetine group (FLX), NAC group and control group (n=8 for each group). Rats in CUS group, NAC group and FLX group were all fed alone and received CUS for 6 weeks to establish CUS model. Rats in NAC group and FLX group were given NAC and FLX by daily intragastric administration respectively during the last 3 weeks, while rats in CUS group and control group were given the same volume of solvent. Behavioral assessment including weight measurement, sucrose water consumption test, and opened field test were used for evaluation before and after CUS, and before and after intervention. The concentrations of the monoamine neurotransmitters (NE, DA, 5-HT) in PFC, ST, AM and HIP were measured with Coul array HPLC. Results (1) There were more increases in weight gain, sucrose consumption, and distance of horizontal moving and number of up-right, while the number of feces was less, after intervention in control group, NAC group and FLX group than those of CUS group (P<0.05). (2) Neurotransmitters including NE, DA and 5-HT were significantly decreased in PFC, ST, AM and HIP in CUS group compared with that of control group (P<0.05). The monoamine neurotransmitter (NE, DA and 5-HT) were significantly increased in the brain region (PFC, ST, AM and HIP) in NAC group and FLX group than those of CUS group (P < 0.05). Conclusion NAC and fluoxetine can effectively improve the depressive behavior of the CUS rats, increase the contents of monoamine neurotransmitters including NE, DA and 5-HT in PFC, AM, ST and HIP brain regions.
10.Loop-mediated Isothermal Amplification Method for Detection of Nucleic Acids and its Application
Yan-Yun KUANG ; Si-Guang LI ; Yu-Ping LUO ;
Microbiology 1992;0(03):-
A novel nucleic acid amplification method,termed loop-mediated isothermal amplification(LAMP),which amplifies DNA with high specificity,efficiency,and rapidity under isothermal conditions,may be a valuable tool for the rapid detection of infectious diseases.This method employs a DNA polymerase that have activity of strand displacement DNA synthesis and a set of four specially designed primers that recognize a total of six distinct sequences on the target DNA.LAMP can amplify a few copies of DNA to 109 in less than an hour.The final products are stem-loop DNA with several inverted repeats of the target and cauliflower-like structures with multiple loops.A positive reaction would be shown as a ladder-like pattern in a gel electrophoresis analysis.Because of the advantage,the LAMP method will be widely applied to research of nucleic acid,clinical diagnosis of infectious diseases and detection of genetically modified organisms etc.