1.Promoter methylation of GABRB2 gene in schizophrenia and antipsychotics treatment
Chinese Journal of Nervous and Mental Diseases 2016;42(4):211-215
Objective Gamma amino butyric acid (GABA) signaling pathway related genes mRNA expression and promoter methylation of GABRB2 gene in peripheral blood were investigated to explore the mechanisms involved in schizophrenia (SZ) and antipsychotics treatment. Methods DNA was isolated from blood samples of 53 SZ patients and 53 gender-and age-matched healthy controls. 12 out of 25 SZ patients were followed 8 weeks antipsychotic treatment. The quantitative GABRB2 promoter methylation was analyzed using the high-throughput mass spectrometry on matrix-as?sisted laser desorption/ionization time-of-flight (MALDI-TOF) mass array before and after treatment. Results The GA?BRB2 promoter methylation pattern of case and control group was not significantly different (P>0.05). However, signifi?cant differences of the methylation levels of CpG_28 in the GABRB2 promoter between two groups were found in males [(0.215±0.084) vs. (0.264±0.103), P<0.05]. After 8 weeks antipsychotics treatment, a significant decrease of GABRB2 pro?moter methylatin was detected in the patients [(0.088±0.037) vs. (0.121±0.063), P<0.01]. Conclusion A down regulation of GABRB2 promoter methylation in blood of SZ patients after-treatment supports that GABRB2 promoter methylation in blood may be associated with the mechanisms of antipsychotics treatment in SZ.
2.Organotypic cerebral slice culture and the course of neuronal development in it
Journal of Peking University(Health Sciences) 2003;0(04):-
Objective:To establish a method of organotypic cerebral culture.So as to pave the way for building some neurodegenerative disease models.Methods:Organotypic cerebral cultures were prepared from prefrontal brain of neonatal SD rats. After culturing 7 to 14 days, 3 weeks, 4 weeks and 8 weeks, respectively, cerebral slices were fixed, dehydrated and sectioned in cryostat. The sections proceeded with Nissl staining and neurofilament high molecular weight (NFH) immunohistochemical staining.The difference was observed between controls and cultured slices using normal rats as controls. Results:Nissl staining showed that pyramidal neurons in cultured slices were increased in volume and lightened in staining. The delaminating construction was clear from 1 to 4 weeks after culturing. In cultured slices, immunohistochemical staining showed that NFH positive pyramidal cells appeared on layer Ⅴ on the tenth day and on both layers Ⅴ and Ⅲ after culturing 12 days. In the control group, NFH positive pyramidal cells appeared on layer Ⅴin 5-day-old rats, and appeared on both layers Ⅴand Ⅲ in over 3-week-old rats. In cultured cerebral slices, the number of pyramidal neurons on layer Ⅴ in M1 area was invariable from 12 days to 2 months. Conclusion:Orgaotypic cerebral culture can be used to study postnatal development for neocortex and build some in vitro models for neurodegenerative diseases.
3.Determination of notoginsenoside R_1 and ginsenoside Rg_1, Rb_1 in Xuesaitong Dripping Pills by RP-HPLC gradient elution method
Mei WANG ; Yagang FAN ;
Chinese Traditional Patent Medicine 1992;0(09):-
Objective: A new HPLC gradient elution was studied for the determination of notoginsenoside R 1, ginsenoside Rg 1 and Rb 1 in Xuesaitong Dripping Pills. Methods:C 18 column was used with a mobile phase of acetonitrile water 0~15 min. of (20∶80~40∶60) gradient elution, post time was 5 min, the wavelength of detecter was set at 203nm. Results: The linear range of R 1, Rg 1 and Rb 1 was 1.02~9.18?g,4.8~ 43.4?g and 4.6~41.6?g, respectively, the average recovery rate was 101.0% ( RSD =3.18%), 99.5%( RSD =3.02%) and 100.0%( RSD =1.19), respectively. Conclusion: The method is rapid, accurate, sensitive and relieble. The results show that the method can be used to control quality of products.
4.Determination of Trace Cadmium (Ⅱ) in Water by Spectrophotometry in Cadmium (Ⅱ)-Potassium Iodide-Malachite Green-Gelatine
Journal of Environment and Health 2007;0(09):-
Objective To establish a high sensitive spectrophotometry for determination of trace cadmium in the water. Methods A complicated ion-association complex of Cd(Ⅱ)-potassium iodide-malachite green was formed in the phosphate acid, and the addition of gelatine could enhance the sensitivity of the reaction.The maximum absorption of the ion-association complex was at 680 nm,the effect of experimental conditions such as the reagents concentration,the temperature and the influence of foreign matters were considered.Results In the optimum condition(6.0 ml of 40% potassium iodide-aseorbic acid solution,0.5 ml of 5.0 mol/L phosphate acid solution,0.5 ml of 0.5% gelatine solution,1.5 ml of 1.0?10~(-3)mol/L malachite green solution in a 25ml volumetric flask,diluted with water and mixed well and determined immediately),the linear regression equation was △A=0.011+ 0.957 c,r=0.998 5.Beer's law was obeyed in the range of 0.02 ?g/ml to 0.80 ?g/ml for Cd(Ⅱ)and the limit detection was 0.02 ?g/ ml.The composing ratio of the complex was MG:Cd:I=2:1:4,and its apparent molar absorptivity coefficient was 1.08?10~5 L/(mol? cm).The recovery rates of Cd(Ⅱ)were 97.0%-101.5%,RSDs were 1.36%-3.58%.Conclusion This method is sensitive,simple, rapid and is applicable to the determination of the trace Cd(Ⅱ)in water.
7.Research Progress of Streptomyces Cytochrome P450
Mei LI ; Fan-Rong ZENG ;
Microbiology 2008;0(07):-
Cytochrome P450 are abundant in Streptomyces which play an important role in the biosynthesis of secondary products and metabolism of exotic chemicals of Streptomyces. Recent progress and function of cytochrome P450 in Streptomyces were reviewed in this paper. The problems in study of Streptomyces Cytochrome P450, and the prospects for future study of cytochrome P450 and its application were also discussed.
8.Mitochondrial inhibition induces glutamate excitotoxicity mediated motoneuron death
Mei ZHENG ; Dongsheng FAN ; Jun ZHANG ; Demao SONG ; Shaoguang FAN
Chinese Journal of Neurology 2005;0(11):-
Objective To study the relation between mitochondria damage and glutamate excitotoxicity in motor neuron disease.Methods Organotypic cerebral cultures were prepared from prefrontal brain of neonatal SD rats. Mitochondria was damaged by malonate sodium, and a NMDA receptor antagonist, MK-801 of 0.025,0.050,0.075,0.100 mmol/L, was respectively added into the cerebral cultures simultaneously in the protective experiment. The morphology of motor neurons was shown by Nissl and anti-high molecular weight filament (anti-NFH) immunohistochemical staining, and number of motor neurons was counted. The concentration of MDA in culture medium was measured by MDA assay. Results After exposed to malonate sodium (0, 1, 3, 5 and 7 mmol/L) for 1 week, the number of motor neurons in cerebral slices showed a dose-dependent decrease (49.78?4.30, 47.89?6.81, 25.67?6.18, 4.44?3.40, 1.22?1.99). The group treated with 3 mmol/L malonate sodium was selected as damage group. In protective experiment, the number of motor neurons in 0.050, 0.075 and 0.100 mmol/L MK-801-treated groups was significantly increased as compared with damage group, still less than that of controls. However, there was no difference of number of motor neurons among these three groups. The concentration of MDA in culture medium in normal control and 3, 5 mmol/L malonate sodium was (13.47?0.49), (15.87?0.74), (20.52?0.74) mmol/L. When treating cerebral cultures with 0.050 mmol/L MK-801 and 5 mmol/L malonate sodium simultaneously, the MDA was decreased to 14.45?0.78, close to normal level. Conclusion Glutamate excitotoxicity plays a role in motor neuron diseases caused by mitochondria damage, there exists a close relationship between glutamate exicitotoxicity and mitochondria damage.