1.Progress in mechanisms of methamphetamine-induced dopaminergic neurotoxicity
Xiaofeng ZENG ; Gang LU ; Zhen LI
Chinese Journal of Forensic Medicine 2010;25(1):33-36
Methamphetamine is a powerful stimulant of amphetamine type in the central nervous system (CNS),and recently it has become the major drugs of abuse.A lot of research results show that MA may induce dopaminergic neurotoxicity in the animal and human striatum.The mechanisms include effects on dopaminergic signaling and dopamine oxidation,glutamate induced excitotoxicity,oxidative stress and inflammatory cytokines,disruption of mitochondfia,apoptosis,activation of glial cells and hyperthermia.However the mechanisms by the MA-induced dopaminergic neurotoxicity are not completely understood.The paper reviewed recent progress of study on them to provide reference materials for related research.
2.The diagnostic value of percutaneous transhepatic cholangiography imaging characteristics in pancreaticobiliary maljunction
Xinwei HAN ; Zhen LI ; Gang WU
Chinese Journal of Radiology 2008;42(8):797-801
Objective To investigate the diagnostic value and feasibility of PTC diagnosis on pancreaticobiliary maljunction (IBM), and to summarize the PTC radiological characteristics of PBM. Methods Clinical findings and cholangiopancreatographic results were analyzed retrospectively for a group of consecutive 363 patients with obstructive jaundice receiving the PTCD therapy. Meanwhile the standard selected for cases and diagnostic conditions were established. The length and diameter of pancreaticobiliary common duct, the diameter of pancreatic duct and common bile duct and the confluence angle were measured respectively. The t test and rank sum test were used to analyze the result statistically. Results Thirty-eight cases were radiologicaUy diagnosed as PBM owing to the reference standard and the detection rate was 10.5% (38/363). The length of common duct was (12.6±7.9)mm. The significant difference existed between it and normal value (6ram) (t=5.15 , P <0.05). The site of duodenal papilla had influence on the length of common duct. The diameter of common bile duct, pancreatic duct and common duct near the confluence are (3.7±1.9 ) mm, (2.4±1.3) mm, (3.3±1.4 ) mm, respectively. There was no statistical difference between them and the normal value (t=1.79,2.85,5.72, P>0.05). Fifteen patients' duodenal papilla located the middle of descending duodenum. The length of common duct was (10.6±9.1)mm , the confluence angle was 51.1°±28.0°, the number of the duodenal papilla locating in the inferior 1/3 of descending duodenum, juncture , horizontal part of duodenum was 10, 8,5, respectively. The length of common duet were (9.9±3.7), ( 18.6±8.9), ( 13.9±3.5 ) mm, respectively. The confluence angle were 54.0°±18.6°、48.7°±12.6°、74.4°±18.5°, respectively . The site of duodenal papilla had significant influence on the length of common duct(X2=14.51, P <0.05). Conclusion PTC is a safe, feasible, method to diagnose PBM, and it demonstrates the characteristic findings of PBM.
3.Progress on study of experimental physico-chemical indexes related with ischemic stroke.
Zhi-gang LI ; Mei-zhen ZHU ; Gang-lin WEI
Chinese Journal of Integrated Traditional and Western Medicine 2003;23(4):316-318
Animals
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Calcitonin Gene-Related Peptide
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blood
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Cerebral Infarction
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blood
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Endothelins
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blood
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Humans
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Nitric Oxide
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blood
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Plasminogen Inactivators
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blood
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Thromboxane B2
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blood
4.Identity attestation system for laboratory animal
Dapeng LI ; Zhen LI ; Gang WANG ; Chunlei LV ; Naiyi LI
Chinese Journal of Medical Science Research Management 2013;26(6):413-414
Objective To improve work efficiency and service quality of the laboratory animal service,and to enhance occupational safety against infection for the personnel of laboratory animal center.Methods information technology is employed.Results An identity attestation system for laboratory animal was established,whose functions and operation are explained here.Conclusion The safe identity attestation system for laboratory animal is effective,convenient,and easy to disseminate.
6.Effects of noxious coldness and non-noxious warmth on the magnitude of cerebral cortex activation during intraoral stimulation with water.
Xiuwen YANG ; Hongchen LIU ; Ke LI ; Zhen JIN ; Gang LIU
West China Journal of Stomatology 2014;32(6):552-555
OBJECTIVEWe used functional magnetic resonance imaging (fMRI) to explore the effects of noxious coldness and non-noxious warmth on the magnitude of cerebral cortex activation during intraoral stimulation with water.
METHODSSix male and female subjects were subjected to whole-brain fMRI during the phasic delivery of non-noxious hot (23 °C) and no- xious cold (4 °C) water intraoral stimulation. A block-design blood oxygenation level-dependent fMRI scan covering the entire brain was also carried out.
RESULTSThe activated cortical areas were as follows: left pre-/post-central gyrus, insula/operculum, anterior cingulate cortex (ACC), orbital frontal cortex (OFC), midbrain red nucleus, and thalamus. The activated cortical areas under cold condition were as follows: left occipital lobe, premotor cortex/Brodmann area (BA) 6, right motor language area BA44, lingual gyrus, parietal lobule (BA7, 40), and primary somatosensory cortex S I. Comparisons of the regional cerebral blood flow response magnitude were made among stereotactically concordant brain regions that showed significant responses under the two conditions of this study. Compared with non-noxious warmth, more regions were activated in noxious coldness, and the magnitude of activation in areas produced after non-noxious warm stimulation significantly increased. However, ACC only significantly increased the magnitude of activation under noxious coldness stimulation.
CONCLUSIONResults suggested that a similar network of regions was activated common to the perception of pain and no-pain produced by either non-noxious warmth or noxious coldness stimulation. Non-noxious warmth also activated more brain regions and significantly increased the response magnitude of cerebral-cortex activation compared with noxious coldness. Noxious coldness stimulation further significantly increased the magnitude of activation in ACC areas compared with noxious warmth.
Brain ; Cerebral Cortex ; Cerebrovascular Circulation ; Hot Temperature ; Humans ; Magnetic Resonance Imaging ; Mouth ; Pain ; Water
7.Effect of total thyroidectomy on growth and development of children and adolescents.
Hui-Zheng LI ; Ping-Zhang TANG ; Zhen-Gang XU
Chinese Journal of Otorhinolaryngology Head and Neck Surgery 2008;43(5):381-382
Adolescent
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Body Height
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Body Weight
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Child
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Female
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Growth and Development
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Humans
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Male
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Papilloma
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surgery
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Thyroid Neoplasms
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surgery
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Thyroidectomy
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adverse effects
8.Cationic liposome-mediated enhanced green fluorescent protein plasmid transferred into skeletal muscle satellite cells
Zhifeng XU ; Jinglai LI ; Zhen HAN ; Gang FENG ; Mingming REN
Chinese Journal of Tissue Engineering Research 2013;(46):8056-8061
BACKGROUND:Skeletal muscle satel ite cells are totipotential stem cells with multi-directional differentiation potential, locate in skeletal muscle interstitium, have a certain tolerance to ischemia and hypoxia, and are important cells in stem cellengineering.
OBJECTIVE:To establish a thrifty, convenient culture procedure and create a simple, efficient method to transfect skeletal muscle satel ite cells, and investigate genetic expression after the transfection for cellular cardiomyoplasty.
METHODS:Skeletal muscle satel ite cells were isolated from rabbit thigh and cultured. Their growth curves were determined by CKK-8 method. Grouped by different proportions of the plasmid and liposome, skeletal muscle satel ite cells were transfered by the enhanced green fluorescent protein plasmid based on liposome. After transfection, the efficiency and character of target genetic expression was determined.
RESULTS AND CONCLUSION:Satel ite cells were isolated, cultured and transfected successful y. In suitable ratio of plasmid and liposomes, the transfection efficiency reached up to above 35%. The target protein was expressed within 12 hours after transfection, reached maximum in 48-72 hours and decreased gradual y after one week. The expression stil could be observed two weeks latter. The enhanced green fluorescent protein plasmid conducted by cationic liposome could be transfered into skeletal muscle satel ite cells efficiently. The transfection efficiency was correlated closely to the ratio of plasmid and lipofectamine. The change of target gene expression depended on time.
9.Simultaneous determination of tryptophan and kynurenine in plasma by HPLC with UV detection
Li MA ; Mingjun ZHANG ; Qianna ZHEN ; Gang TIAN ; Min DING
Chinese Journal of Laboratory Medicine 2011;34(12):1057-1061
ObjectiveTo establish an accurate method for simultaneous determination of plasma Kyn and Trp by HPLC-UV detection.Methods Kyn and Trp were separated on Agilent Hypersil ODS column using 3-nitrotyrosine as internal standard.The mobile phase consisted of 15 mmol/L sodium acetateacetic acid (pH 5.5):acetonitrile 94∶ 6(v/v) at a rate of 0.8 ml/min.The chromatographic separation was performed at 25 ℃.The eluate was monitored with programmed wavelength setting at 360 nm from 0 to 4 min for Kyn and at 302 nm from 4 to 5 min for Trp.The method was applied to determination of plasma Kyn and Trp in 8 chronic glomerulonephritis,10 idiopathic thrombocytopenic purpura,15 chronic hepatitis B virus patients and 15 healthy controls from September to December in 2010.The differences were compared using ANOVA and SNK methods.Results The retention time of Kyn and Trp were 2.9 min and 4.4 min,respectively.For Kyn,the assay was linear from 0.44 μmol/L to 18.30 μmol/L.For Trp,the linearity was from 3.67 μmol/L to 470.00 μmol/L.The detection limits were 0.014 μmol/L for Kyn and 0.122 μmol/L for Trp,respectively.The within-day CVs were < 3% and the between-day CVs were < 4%.The mean recoveries yield were in the range of 92.29 to 104.40.The plasma concentrations of Kyn were ( 1.59 ± 0.28),(2.73 ± 0.56),(2.69 ± 0.44) and ( 1.54 ± 0.48 ) μmol/L,the plasma concentrations of Trp were (59.8 ± 10.0),(46.1 ± 11.7),(58.5 ±8.0) and (41.4±13.1) μmol/L,the Kyn/Trp were (0.027 4±0.007 5),(0.061 6 ±0.016 5),(0.046 7 ±0.009 1) and (0.038 3 ±0.007 5)in controls,chronic glomerulonephritis patients,idiopathic thrombocytopenic purpura patients and chronic hepatitis B virus patients,respectively.There were significance difference of Kyn,Trp and Kyn/Trp amony the four groups (F=23.734,8.463,20.921,all P<0.01).Conclusion The method is simple,fast,and suitable for applicability to clinical measurement.
10.Effects of Propafenone on Action Potential of Rabbit Ventricular Myocytes and the Use-dependent Block of Transient Sodium Current
Jing LI ; Xiaoyun ZHENG ; Gang ZHOU ; Yuetao ZHAO ; Zhen YANG
Chinese Circulation Journal 2015;(7):679-683
Objective: To study the effects of propafenone on action potential (AP) of rabbit ventricular myocytes with the tonic block and use-dependent block of transient sodium current (INa-T). Methods: A total of 10 adult New Zealand white rabbits were sacriifced and 10 individual ventricular myocytes were isolated by enzyme digestion method. Microelectrode technologies were used to record AP-related parameters: maximum diastolic potential (MDP), maximum rate of rise of the action potential upstroke (Vmax), action potential amplitude (APA) and action potential duration at 20%, 50% and 90% (APD20, APD50 and APD90).INa-T was measured, I-V curves and peak currents at different frequencies were detected by whole cell patch clamp before and after propafenone perfusion at 10 μmol/L. Results: There was no statistical difference in MDP at before and after propafenone perfusion as (-80 ± 6) mV vs (-82 ± 5) mV,P>0.05. After perfusion, APA was signiifcantly decreased as (95 ± 12) mV vs ( 125 ± 10) mV,P<0.05, the Vmax slowed down as (330 ± 43) V/s vs (420 ± 54) V/s,P<0.05, while APD20, APD50 and APD90 were unchanged as (8 ± 2) ms vs (6 ± 2) ms,P>0.05, (16 ± 3) ms vs (12 ± 3) ms,P>0.05 and (86 ± 14) ms vs (85 ± 12) ms,P>0.05. After propafenone perfusion, I-V curve ofINa-T was shifted upward and the peak current was decreased as (3001 ± 383) pA vs (4193 ± 378) pA, P<0.05. Before perfusion, when stimulated at 0.06 Hz, 1 Hz, 2 Hz, 5 Hz and 10 Hz, there were no signiifcant use-dependent block inINa-T , and no real difference inINa-T between the 10th and 1st pulse,P>0.05. After perfusion, no significant use-dependent block was observed when stimulated at 0.06 Hz and 1 Hz,P>0.05, while at 2 Hz, 5 Hz and 10 Hz, propafenone perfusion demonstrated signiifcant use-dependent block uponINa-T with the inhibition fractions of (22 ± 11)%, (38 ± 14)% and (52 ± 17)% respectively, those were signiifcantly different from the inhibition fractions at either 0.06 Hz or 1Hz,P<0.05. When the inhibition fractions were compared by each 2 conditions, allP<0.05. Conclusion: Propafenone may slow down the Vmax of AP, reduce APA and without the impact on APD; the effects onINa-T is not only in tonic block, but also more obviously in use-dependent block in isolated ventricular myocytes of New Zealand rabbit. Such inlfuences minimized the impact on QT interval and meanwhile, decreased the incidence of brad arrhythmia.