1.Effect of Salvia miltiorrhiza injection on hyperpolarization-activated current channels in dorsal root ganglion neurons of rats
Acta Pharmaceutica Sinica 2006;41(11):1038-1043
Aim To explore the modulation of Salvia miltiorrhiza on hyperpolarization-activated current (Ih) channels in dorsal root ganglion (DRG) neurons of rats and identify the mechanism of Salvia miltiorrhiza in alleviating pain and inhibiting calcium overload. Methods The effect of Salvia miltiorrhiza injection on Ih channels in DRG neurons of rats were examined by using whole-cell patch clamp technique. Results The experimental results showed that the amplitude of Ih evoked by -150 mV was (-1.06±0.18) nA. The Ih could be fitted well into the single kinetics and the time constant of activation, τ was clearly voltage-dependent with τ=(322.14±28.81) ms at -100 mV, decreasing to τ=(62.51±9.78) ms at -150 mV. The reversal potential of Ih was (-35.03±1.12) mV measured from tail currents. But no significant differences were found between the DRG neurons in the absence and presence of Salvia miltiorrhiza injection (10%, 25%, 50%) in the current amplitude, the time constant of activation and the reversal potential. The only difference between the DRG neurons in the absence and presence of Salvia miltiorrhiza injection was the half-activation potential of Ih. In control recordings the half-activation potential was (-106.07±3.59) mV. By comparison, the half-activation potentials changed to (-111.59±3.79) mV (n=31 neurons, P<0.05), (-119.37±4.96) mV (n=31 neurons, P<0.05) and (-121.23±3.86) mV (n=31 neurons, P<0.05) in the presence of 10%, 25%, 50% Salvia miltiorrhiza injection, respectively. Conclusion Only the half-activation potential of Ih in the arthritic and neuropathic rat models shifted in the depolarizing direction, which increased the electrophysiological activity of Ih and made it related to peripheral hyperalgesia. The selective inhibition of Salvia miltiorrhiza on the electrophysiological activity of Ih may be one of the mechanisms underlying its analgesic effects.
2.DIAGNOSIS AND TREATMENT OF DIFFUSE AXONAL INJURY
Xiangming FANG ; Yili CHEN ; Haipeng GAN
Chinese Journal of Postgraduates of Medicine 2001;24(5):30-31
Objective To provide a description of clinical manifestations, special imaging features and treatment of diffuse axonal injury(DAI).Methods Retrospective analysis of 32 cases of diffuse axonal injury.Result 87.5% patients were involved in traffic accident. All patients came into persistent comatose state immediately. 75% patients had abnormal CT scan findings. MRI showed more sensitive. It could reveal injury appearance of corpus callosum and brain stem clearly. Hypothermic therapy and calcium ion antagonist were used. Conclusions combination of clinical manifestations and special imaging features helped to diagnosis of DAI in early stage. Intensive care and preventing secondary brain injury were the important treatment points.
3.Effects of static tensile strain on the production of prostaglandin E_2 by hum an periodontal ligament fibroblast
Jun HU ; Xiangming ZHENG ; Xinming CHEN
Journal of Practical Stomatology 2000;0(06):-
Objective: To study the effects of static tensile strai n on the secretion of prostaglandin E 2 (PGE 2) of human periodontal ligament fibroblasts (PLFs). Methods: Human PLFs were treated by tensile strain values of 0%,8%,12%,16% and 20% for 24, 48 and 72 h respecti vely with a self-devised loading apparatus in vitro. All samples were rando mly allocated into 15 groups and there were 3 in each group. After treatment cu lture media of the samples were collected and the content of PGE 2 in each medi um sample was determined using RIA ELISA. The data analysis was carried out with SPSS using Dunnett test. Results: In group of 0% the sec retion of PGE 2 by PLFs per day had no relation with loading time; E 2 secre tion increased with the increace of loading time and with the tensile strain va lue in the group of 8%,12% and 16%(P
4.Monitoring of Electrophile Chemical Pollutants Using Transgenic Firefly Luciferase Gene Cells
Xiangming LI ; Fangni LUO ; Chunbo CHEN
Journal of Environment and Health 2007;0(07):-
Objective To assess quickly the potential environmental pollution by using the luciferase transgenic cells. Methods Many electrophile compounds in the environment can generate oxidative stress,so that the transcription of certain protective genes is induced via specific DNA motifs called electrophile response elements (EPREs). We have made a vector containing a single EPRE fused to the TK minimal promoter and the gene encoding firefly luciferase (EPRE-LUC) by adopting bio-molecular techniques. From this vector the stable LUC expression vector regulated by EPRE had been successfully reconstructed. This reporter construct was transfected into HeLa cells,and the clones resistant to G418 were selected. The resistant cells were treated by the different concentrations of sodium arsenate(NaAsO2),cadmium chloride (CdCl2),mercury chloride(HgCl2) and diethyl mateate (DEM). After that,the expression of luciferase was determined by luciferase assay kit. Results The correct construct frame of LUC reporter vector regulated by EPRE was identified by DNA sequencing; the dose-dependent relationships between the LUC expression and the test substance concentration were found. Among them,the relationship produced by DEM was the most significant. Conclusion The LUC transgenic cells regulated by EPRE have been successfully constructed.
5.Development of a Rapid Screening System of Environmental Estrogen Based on Recombinant Yeast Cell
Xiangming LI ; Fangni LUO ; Chunbo CHEN
Journal of Environment and Health 1992;0(02):-
Objective To develop a rapid screening method of environmental estrogen in vitro. Methods Estrogen responsive element (ERE) was inserted into the upstream of Lac Z (?-galactosidase ) reporter gene and the reporter gene was regulated under estrogen receptor(ER) in the recombinant yeast cells by the molecular biological technique. When the yeast cells was affected by environmental estrogen, conformational change of ER lead to expression through binding to ERE. There exist the functional relationships between the expression and the pollution degree of environmental estrogen. Therefore, the pollution degree can be reflected by assaying the activity of ?-galactosidase. Results It was identified by PCR that recombinant yeast cell, whose Lac Z reporter gene regulated under estrogen receptor, was successfully reconstructed. The experimental results showed that the time-dose-effect response had no significant changes when the recombinant yeast cell bad been exposed to ?-estradiol for 4 and 8 hours respectively; among the three methods of yeast disintegration, the ultrasonic vibration method had more advantage compared with that of the other methods and this dose-effect curve exhibited "S" shape; among 3 test chemical products, ?-estradiol was the most estrogenic activity, biosphenol A take second place, estradiol benzoate was the lowest. Conclusion The assay system of yeast cell for environmental estrogen hormone mediated by estrogen receptor is stable and applicable.
6.Effects of cardiopulmonary bypass on plasma levels of procalcitonin and cytokines
Xiangming FANG ; Qiang SHU ; Qixing CHEN
Chinese Journal of Anesthesiology 1994;0(01):-
ve To investigate the changes in perioperative levels of circulating procalcitonin (PCT), TNF-?, IL-6, IL-8 and IL-10 in patients undergoing valve replacement with cardiopulmonary bypass (CPB) .Methods Sixteen patients (7 male, 9 female) aged (38.5?5.1) years and weighing (42.9?10.2) kg, undergoing valve replacement under CPB were chosen in this study as CPB group and seven male patients aged (32.6?5.1) years and weighing (58.3?4.4) kg undergoing pericardectomy were enrolled in this study as non-CPB group. Patients with infection or immunodeficiency and those who had received corticosteroid and drugs which may affect immune function were excluded. Premedication consisted of intramuscular midazolam 0.1 mg/kg and morphine 0.1 mg/kg. Anesthesia was induced with midazolam 0.15mg/kg, fentanyl 8?g/kg and vecuronium 0.1mg/kg and maintained with 0.8%-1.2% isoflurane inhalation and intermittent iv boluses of fentanyl and vecuronium. Blood samples were taken from CVP line before induction of anesthesia, 5 min after tracheal intubation, before CPB, immediately after discontinuation of CPB, and on 1st, 3rd, 5th, 7th postoperative day for determination of plasma PCT, TNF-?, IL-6, IL-8, and IL-10 levels. Results In CPB group plasma TNF-?, IL-6, IL-8 and IL-10 levels increased significantly immediately after CPB and returned to the baseline levels on the 3rd postoperative day, while plasma PCT concentration increased significantly after operation and reached its peak level of (10.62?3. 51) ng/ml on the 1st postoperative day. In non-CPB group there was a similar trend of changes in PCT , IL-6, IL-8 and IL-10 but to a much lesser extent.Conclusions CPB leads to a pro- and anti-inflammatory response, as well as procalcitonin release. PCT may play an important role in the systemic inflammation induced by CPB.
7.Differential expression of ?-and ?-defensin in human peripheral blood
Xiangming FANG ; Jing XU ; Qixing CHEN
Chinese Journal of Anesthesiology 1995;0(10):-
Objective To examine the expression of a- and ?-defensin genes in human peripheral leukocytes. Methods Fifty-one healthy blood donors were studied. Peripheral leukocytes were stimulated by lipopolysaccharide ( LPS) 100 ng?ml-1 ex vivo. The level of defensin mRNA expression in the leukocytes were assessed after being incubated with LPS for 0 (baseline), 1, 3, 6, 12, 24 h by semi-quantitative RT-PCR. Southern blot analysis and sequencing were used to confirm the identity of defensin gene transcripts. Results Expression of ?-defensin 1-3 mRNA was detected in all donors studied, but no ?-defensin mRNA expression was detected in peripheral leukocytes before LPS-stimulation. Expression of ?-defensin-1 gene was detected in the leukocytes after being incuaated with LPS for 3 h in 45 of 51 donors (88.2% ) and ?-defensin-2 mRNA expression was positive in 20 donors (39.2 % ), but no ?-defensin-3 mRNA expression was detected. The levels of ?-defensin-1 and-2 mRNA peaked at 6 h and started decreasing at 12 h. In contrast there was no significant change in ?-defensin 1-3 mRNA in peripheral leukocytes after LPS-stimulation. Conclusion In human peripheral leukocytes ?-defensin-1 and-2 genes are induced transiently by LPS-stimulation;whereas ?-defensin 1-3 genes are constitutive. The induced expression of ?-defensin-1 and-2 genes show inter-individual variability.
8.Loureirin B inhibits capsaicin-induced currents in rat dorsal root ganglion neurons
Can WANG ; Su CHEN ; Xiangming LIU
Chinese Pharmacological Bulletin 1987;0(02):-
Aim To investigate effects of loureirin B on capsaicin-evoked currents in rat dorsal root ganglion (DRG) neurons. Methods In acutely isolated rat DRG neurons, effects of loureirin B on capsaicin-evoked currents were observed using whole-cell patch-clamp technique. Results ① The holding potential was maintained at -60 mV and VR1 antagonist capsazepine inhibited capsaicin-evoked currents completely; ② Loureirin B concentration-dependently inhibited capsaicin-evoked currents. Loureirin B at the concentrations of 2.0, 4.0, 8.0 and 16.0 ?mol?L-1 reduced capsaicin-evoked currents by 15.36%?2.12%、36.41%?2.43%、76.26%?2.16% and 96.69%?3.21% (n=10, P
9.The multisection spiral CT perfusion imaging on acute pancreatitis and correlated with clinical criteria
Fangjun WANG ; Pengfei LIU ; Weichang CHEN ; Liang GUO ; Xiangming FANG
Chinese Journal of Pancreatology 2009;9(4):238-240
Objective To investigate the blood perfusion characteristic of acute pancreatitis (AP) using multisection dynamic CT. To detect the changes of the perfusion parameters in patients with AP and assess the value of the perfusion parameters as severity indicators in AP. Methods 120 cases (34 cases of normal pancreas and 86 cases of AP) were examined for pancreatic perfusion from August 2006 to April 2008. The multisection dynamic CT perfusion series was performed by a multisection CT scanner (Siemens somatom Sensation 64) and the perfusion parameters, including BF, BV, TTP, PS, were collected and were compared with APACHE Ⅱ score, Ranson score, CRP, CTSI, time to abdominal pain cessation, length of hospital stay and complication rate for correlation analysis. Results The mean BF, BV, TTP and PS in AP patients were (113.57 ±50.04) ml · 100 mg~(-1) · min~(-1), (146.61 ±45.11) ml/L, (148. 88 ±21. 16) 0.1 s, (119.53± 52.36) 0. 5 ml · 100 ml · min , respectively; when compared with normal control, BF, BV decreased significantly (P<0.05) , while the change of TTP, PS were not statistically significant. Both BF and BV were correlated with APACHE II score, Ranson score, CRP, CTSI (P<0. 05) , as well as the time to abdominal pain cessation, length of hospital stay and complication rate (P < 0. 05). Conclusions Pancreatic vessel perfusion was decreased in AP. Both BF and BV were correlated with APACHE Ⅱ score and Ranson score, CRP, CTSI, and could be used to predict severity of acute pancreatitis.
10.Evaluation of cardiac contractility and relaxation during no-reflow phenomenon by the combination of Doppler tissue imaging with myocardial contrast echocardiography
Yang JIAO ; Lixin CHEN ; Hong TAO ; Xiangming ZHU
Chinese Journal of Clinical Pharmacology and Therapeutics 2008;13(1):79-84
AIM: To evaluate the cardiac contractility and relaxation by Doppler tissue imaging (DTI) combined with myocardial contrast echocardiography (MCE) via injection of contrast media, Albunex. METHODS: Nineteen healthy mongrel dogs were conducted 60 min ligation of left anterior descending coronary artery (LAD), followed by reperfusion of 60, 120 and 180 min to establish an acute myocardial ischemic-reperfused canine model. (1) MCE was performed by bolus injection of Albunex at pre-reperfusion and at post-reperfusion. The perfused defect area defined by MCE at pre-reperfusion was regarded as risk area (RAMCE), while perfused defect area at post-reperfusion was regarded as no-reflow area (NRAMCE). When the ratio of NRAMCE to RAMCE exceeded 25%, myocardial reperfusion was considered incomplete, I.e., no-reflow group; If the ratio was <25%, myocardial reperfusion was considered adequate, I.e., reflow group. (2) Left ventricular ejection fraction (LVEF) and wall thickness ratio (△T%) of LV anterior wall were determined. (3)S-wave, e-wave and a-wave velocities at the LV anterior wall were determined by DTI. The e/a ratio was measured. RESULTS: The results of MCE showed 7 dogs in reflow group and 10 dogs in no-reflow group. (1) LVEF in reflow group gradually increased with time course after myocardial reperfusion, and in no-reflow group, however, LVEF increasingly declined with ongoing myocardial reperfusion. At the same reperfusion time point, LVEF of no-reflow group was significantly lower than that of reflow group. (2) △T% in reflow group improved gradually, and however, it can not come back to that of baseline at 180-min reperfusion. △T% in no-reflow group had no signal of recovery with progressive reperfusion. (3) S-wave, e-wave velocities measured by DTI significantly declined after ligation of LAD, and a-wave velocity increased, leading to decline of e/a. After myocardial reperfusion, s-wave, e-wave velocities and e/a in reflow group gradually increased at post-reperfusion, and a-wave velocity somewhat declined. In no-reflow group, on the other hand, s-wave, e-wave velocities and e/a progressively declined and a significant difference was present between reflow group and no-reflow group (P<0.05). CONCLUSION: Cardiac contractility and relaxation can not be recovered during myocardial microvascular impairment. This change may be further deteriorated with size enlargement of no-reflow area. DTI may provide a sensitive, reliable method for quantifying cardiac contractility and relaxation.