1.Effect of brain tissue extract after acupuncture preconditioning on cerebral ischemia-reperfusion injury in rats
Zebin CHEN ; Fengxia LIANG ; Fang YUAN ; Hua WANG
Chinese Journal of Tissue Engineering Research 2005;9(29):246-248
BACKGROUND: According to the thought "prevention of diseases", a conception of "strengthening the vital by acupuncture preconditioning (AP)" is suggested recently.OBJECTIVE: To investigate the effect of brain tissue extract after AP on cerebral ischemia-reperfusion injury.DESIGN: Random control experiment.SETTING: Institute of Acupuncture & Moxibustion and Massage, and Department of Anatomy and Embryology, Hubei College of Traditional Chinese Medicine.MATERIALS: Totally 102 adult Wistar rats were selected during the experiment, which was completed in the Institute of Acupuncture & Moxibustion and Massage of Hubei College of Traditional Chinese Medicine from September 2003 to July 2004. Among them, 20 rats were used to prepare cerebral tissue extract, and another 82 were used in the subsequent experiment.METHODS: The brain tissue extract was obtained from the rats which were given electroacupuncture at Shenshu (BL-23) and Baihui (DU-20).Totally 82 rats were randomly divided into 6 groups. Five rats in blank control group were taken as blank control, 15 in sham-operation control group were performed with sham operation, 16 in cerebral ischemia-reperfusion control group with cerebral ischemia-reperfusion, 16 in saline control group with the injection of saline intravenously firstly and then cerebral ischemia-reperfusion modeling, 15 in normal cerebral tissue extract control group with the injection of normal cerebral tissue extract intravenously firstly and then cerebral ischemia-reperfusion modeling, and 15 in AP cerebral tissue extract group with the injection of cerebral tissue extract intravenously firstly and then cerebral ischemia-reperfusion modeling.Intravenous injection was performed 2 hours and 1 hour before cerebral ischemic modeling, and each rat was injected twice with 1 mL/time. Brain tissue of the rats was taken ont 1, 3, 7 days after reperfusion respectively (or each group was divided into 3 subgroups with 5 rats in each) except those in blank control group. The blain tissue of rat in each group was selected at the relevant time points, and embedded with paraffin and cut into pieces. Cerebral histopathology was observed under the light scope (× 400)and the survival neurons were counted whose area was layer y of region Ⅰ in parietal cortex (inner cone).cortex.RESULTS: Two rats died during the experiment in cerebral ischemiareperfusion control group and saline control group respectively. Another Except blank control group and sham operation group, the brain sections of different time points in other groups showed scattering ischemic anoxic Count of survival neurons in layer Ⅴ of area I in parietal cortex: One day after reperfusion, survival nerve density of the brain ischemic reperfusion model group [(338.8±31.2)/mm2] was significantly lower than that of blank control group [(753.4±60.8)/mm2] (F=129.36, P < 0.05); degeneration of the nerves became worse after reperfusion for 3 days and 7 days, but with no significant difference (F=1.76, P > 0.05). There was no significant difference between the saline control group, normal brain tissue extract group and brain ischemic reperfusion model group at different time points (F=1.76, P > 0.05). Survival neuron density in group of brain tissue extract after AP at the three time points was significantly higher than that in brain ischemic reperfusion model group [(438.1±41.0), (338.8±31.2)/mm2,(296.4±27.1), (124.8±13.4)/mm2; (269.5±30.4), (1.324±0.157)/mm2;F=129.36, P < 0.05].CONCLUSION: Injection of the brain tissue extract after AP at Shenshu (BL-23) and Baihui (DU-20) into the celiac cavity of rats could obviously reduce the subsequent neuron loss induced by brain isehemia-reperfusion and protect brain from ischemia-reperfusion injury.
2.Effects of histamine on mRNA expression of Egr-1 in astrocytes
Yuan QIAO ; Yan LIAO ; Fang NAN ; Yueqin LIANG ; Yanying FAN
Chinese Journal of Pathophysiology 2016;32(4):680-685
AIM:To explore whether histamine can regulate the expression of early growth response factor-1 (Egr-1) in the cerebral cortex astrocytes.METHODS:Normal wild-type (WT) mice, histidine decarboxylase knockout ( HDC-KO) mice and histamine treated HDC-KO mice were sacrificed for extracting the total RNA of the cerebral cortex. Primary cultured rat cortical astrocytes were treated with histamine at concentrations of 10 -8 , 10 -7 , 10 -6 , 10 -5 or 10 -4 mol/L for 15, 30, 60, 120 or 240 min.H1 or H2 receptor antagonists were pretreated for 15 min before histamine treat-ment.After histamine treatment, the cell total RNA or protein was extracted.The expression of Egr-1 at mRNA and protein levels was determined by real-time PCR and Western blot.RESULTS:The mRNA level of Egr-1 in cerebral cortex of HDC-KO mice was significantly lower than that in WT mice, while exogenous histamine induced the mRNA expression of Egr-1 in HDC-KO mice.In cultured astrocytes, histamine induced the mRNA expression of Egr-1.The maximum increase in the mRNA level of Egr-1 was produced by histamine at concentration of 10 -5 mol/L.In addition, histamine-induced Egr-1 mRNA accumulation peaked at 30 min after commencing stimulation, while histamine significantly increased Egr-1 protein expression at 60 min.Furthermore, histamine-induced Egr-1 expression was inhibited by H1 receptor antagonist but not H2 receptor antagonist.CONCLUSION:Histamine up-regulates the Egr-1 expression in cerebral cortex and cultured astrocytes, which may attribute to H1 receptor activation.
3.Protective Mechanism of Salvianolic Acid B on Myocardial Ischemia-reperfusion Injury of Rats
Liang ZHANG ; Dongping YUAN ; Li XU ; Baoping JIANG ; Taihui FANG
Traditional Chinese Drug Research & Clinical Pharmacology 2000;0(06):-
Objective To investigate the protective mechanism of Salvianolic acid B (Sal B) on experimental in-vivo myocardial ischemia-reperfusion injury (MIRI)in rats. Methods Rats model of myocardial ischemia-reperfusion injury was induced by ischemia for 60 min and then reperfusion for 60 min. After treatment,endothelin (ET) levels in plasma and the homogenate of myocardial tissue,and serum levels of nitric oxide (NO) and NO synthase were measured. Meanwhile,the pathological changes of myocardial tissue were also observed. Results Compared with the model group,middle-dose and high-dose Sal B could depress the ET levels in the plasma and the myocardial tissue,and increase the content of serum NO and NOS (P
4.Modeling of a controllable acute regional cerebral ischemia in rats and evaluation with CT perfusion imaging and histopathology
Chenyang LIANG ; Peiyi GAO ; Fang YUAN ; Lixin XU ;
Chinese Journal of Radiology 2001;0(03):-
Objective To establish a stable and controllable model of acute regional cerebral ischemia in rats, and to evaluate it by CT perfusion imaging and histological study. Methods Twenty eight male Wistar rats were randomly divided into 4 groups, and there were 7 rats in each group. The sham operation rats were defined as the first group, rats suffered from cerebral ischemia for 15 minutes were classified as the second group, rats suffered from cerebral ischemia for 30 minutes and then reperfusion for 1 hour as the third group, and rats suffered from hypo perfusion for 6 hours as the fourth group. Cerebral ischemia or hypo perfusion were induced by inserting a nylon thread of different diameter into right middle cerebral artery (MCA) of rats under the monitoring of regional cerebral blood flow (rCBF) by the Laser Doppler Blood Perfusion Monitor (BPM). rCBF was also examined by dynamic CT perfusion imaging. At the end of the observation time, rats were decapitated, and three rats of each group were performed 2,3,5 triphenyltetrazolium chloride (TTC) staining and four rats were performed histological study. Results In the second group, rCBF was controlled within 5% to 22% under the monitoring by BMP and CT perfusion imaging showed the decreased rCBF in 7 rats, but TTC staining showed red appearance indicating no infarction focus formed. Electronic microscopic study revealed astrocytic swelling and a few of neuronal degeneration. In the third group, rCBF was controlled within 4% to 23% under the monitoring by BMP. There were more severe astrocytic swelling and a lot of neuronal degeneration. The abnormal areas in CT perfusion images were the same as TTC staining. In the fourth group, in accordance with less decrease ment of rCBF (from 38% to 55%) in 7 rats, there were obvious astrocytic swelling and subtle neuronal degeneration. TTC stain did not show ischemia area. All these abnormal changes were not observed in the sham operation rats. Conclusion The controllable acute regional cerebral ischemic model in rats is very stable and repeatable. It can be simulated into the ischemic state of different perfusion level. This model is suitable for the research of acute cerebral infarction and regional cerebral ischemia. The facts that parallel changes existed among BMP measurement, CT perfusion imaging, and brain histology indicated that CT perfusion imaging is accurate and sensitive in evaluating acute regional ischemia.
5.CT perfusion imaging on the disturbance of regional cerebral microcirculation in a pre-infarction period : an experimental study
Peiyi GAO ; Chenyang LIANG ; Yan LIN ; Fang YUAN ; Ling HU
Chinese Journal of Radiology 2001;0(08):-
Objective To investigate the CT perfusion imaging and the pathological features on the disturbance of regional cerebral microcirculation in a pre-infarction period, and to evaluate the relationship between the astrocytes and regional cerebral microcirculation. Methods Dynamic CT perfusion imaging of the models with regional cerebral hypoperfusion and astrocytic swelling in rats was performed to assess the presence or absence of the disturbance of regional cerebral microcirculation. Then, the histopathologic examination was made for both models, respectively. The ratios of side-to-side were measured at hypoperfusion areas in the models of regional cerebral ischemia. Results Regional hypoperfusion was revealed by regional cerebral blood flow (rCBF) and mean transit time (MTT) maps in the group of hypoperfusion for 6 hours. Regional cerebral blood volume (rCBV) and time-to-peak (TTP) maps were normal in that group. The ratios of rCBF, rCBV, MTT and TTP were 0 39-0 55, 0 92-1 00, 1 20-1 50 and 1 00-1 00 respectively. Astrocytic swelling pressing the capillary wall was obvious and subtle neuronal reversible degeneration was occasionally found. TTC stain was normal. In the tACPD group of astrocytic swelling, the abnormal hemodynamic regions on rCBF and MTT maps were found. The rCBV maps of 3 rats in the tACPD group showed the area of reduced rCBV. In 2 rats of tACPD group, the areas of delayed TTP were also found. The ratios of rCBF, rCBV, MTT and TTP were 0 25-0 44, 0 70-1 01, 1 20-2 00 and 1 02-1 45 respectively. TTC stain was negative. Electron microscope study revealed remarkable swelling of astrocytes, especially endfoot processes of astrocytes around capillaries. The abnormal hemodynamic region on rCBF and MTT maps matched with abnormal extent on histopathologic examination. The rCBV and TTP maps appeared normal. Conclusion The astrocytes can react in a way faster than the neurons in the pre-infarction period, viz. astrocytic swelling. The swelling of astrocytic foot, which pressed capillary vessel, induced the disturbance of regional cerebral microcirculation, and then aggravated hypoxic ischemic state in regional brain parenchyma. Perfusion CT and its parameters' analysis may play an increasing role to delineate the reversible hypoperfusion areas in pre-infarction period. Analyzing the relationship of rCBF and rCBV is very helpful to know the status of the capillary vessels in regional cerebral hypoperfusion area.
6.Synonymous Codon Usage Bias and Overexpression of a Synthetic Gene Encoding Interferon α2b in Yeast
Bin, FANG ; Bu-feng, LIANG ; Guang-yuan, HE
Virologica Sinica 2007;22(3):226-232
To achieve higher level expression of Interferon α2b (IFN-α2b) in methylotrophic yeast (Pichia pastoris), a cDNA fragment coding for the mature IFN-α2b was designed and synthesized based on the synonymous codon bias of P. pastoris and optimized G+C content. The synthetic IFN-α2b was inserted into the secreted expression vector pPICZαA, and then integrated into P. pastoris GS115 genome by electroporation. Multi-copy integrants in the Mut+ recombinant P. pastoris strain were screened by high concentrations of Zeocin. 120 hours culturing allowed expression of the IFN-α2b transformant up to 810 mg/L as detected by SDS-PAGE and quantitative methods. In addition, Western blot analysis showed that the recombinant proteins had immunogenicity. The significant antiviral activity of the recombinant IFN-α2b protein was verified by WISH/ VSV system, which was 3.3×105 IU/mL.
8.A clinical and etiological analysis of candida urinary tract infections in intensive care unit
Li WANG ; Liyan ZHANG ; Fang LIU ; Lina YUAN ; Hui LIANG ; Yunzhuo CHU
Chinese Journal of Postgraduates of Medicine 2008;31(13):21-24
Objective To investigate the clinical characteristics, risk factors and pathogenic disposition of candida urinary tract infections in intensive care unit(ICU)patients. Methods A retrospective review and analysis of clinical information and urine culture of 83 ICU patients with the candida urinary tract infections. Results All patients had severe underlying diseases one or more complication and/or concomitant diseases were existed at the same time. All of the patients previously used broad-spectrum antibiotics and received invasion in diagnosis and therapy: indwelling urinary catheters, mechanical ventilation, incision of trachea, deep artery or vein operation with catheters indwelling, surgical operation and indwelling drainage tube (96.39%, 95.18%, 69.89%, 46.99%, 43.37%, 33.73%, respectively). In all the patients, 62.65% patients were elder. Hospitalization days of 54.22% patients staying in ICU were above 31 days. Mortality rate was in 39.76%( 33 cases ). C.tropicalis(55.91%) and C.albicans(35.48%) were the major pathogens. Seventy-four cases( 89.16%)were infected by one candida specie, and 9 cases( 10.84% )were infected by two or three candida species. The positive blood culture was found in 9 cases ( 10.84% ) also. Conclusions The ICU patients with severe underlying diseases and high risk factors may have candida urinary tract infections easily. C.tropicalis and C.albicans are the most common pathogens. Some candiduria is the evidence of candidemia.
9.Effect of epidural drainage and dural tenting suture on epidural hematoma in 145 cases of craniotomy
Jie ZHAO ; Zhixiong LIU ; Yunsheng LIU ; Jinfang LIU ; Wenhua FANG ; Yihua RAO ; Liang YANG ; Xianrui YUAN
Journal of Central South University(Medical Sciences) 2010;35(3):273-276
Objective To evaluate the efficacy of dural tenting suture and epidural drainage in craniotomy. Methods In 145 cases of intracranial lesions, dural tenting suture and epidural drainage were performed to prevent epidural hematoma. Results Postoperative computed tomography (CT) showed no epidural hematoma required surgery in both groups. Conclusion Both dural tenting suture and epidural drainage are effective in preventing epidural hematoma. Hemostasis is the key step. Dural tenting suture without epidural drainage relieves psychological stress. It decreases the risk of intracranial infection and avoids some unusual complications.