BACKGROUND: The dynamic characteristics of electroencephalogram (EEG) include a decrease in the chaotic dimension, the correlation dimen sion, the Lyapunov exponent, the chaotic complexity, the freedom of EEG and an enhanced synchronization and periodicity of the EEG from several minutes to tens of minutes before epileptic seizures. All these characteristics prefigure the forthcoming seizures. Some studies have proven that the non linear dynamical system can be used as a feasible approach to explore the potential variables for describing the chaos portrait of EEG. OBJECTIVE: To analyze the electric characteristics of EEG signal in the epileptic seizures in rat model by investigating the nonlinear dynamical variables, such as the approximate entropy (ApEn) and correlation dimen sion. DESIGN: Observational and experimental study based on animals. SETTING: Department of Medical Engineering, Department of Gastroen terology, Second Artilleryman General Hospital of Chinese PLA; Department of Physics, Faulty of Biomedical Engineering, Fourth Military Medical Uni versity of Chinese PLA. MATERIALS: From September 2001 to January 2002, this study was conducted at the Complexity Laboratory of the Biomedical Department of the Fourth Military Medical University of Chinese PLA. Six male SD rats,weighing 150- 200 g, were selected.INTERVENTIONS: After intraperitoneal injection of chloral hydrate (0. 5 mL), the male SD rats were deeply anesthetized. When their EEG signal became stable, bemegride injection was diluted at 1:1 with saline and was given on a volume of 0.5 mL to the rats intraperitoneally. After a while,the epileptic seizures started marked by a spasm with a deep roar. The entire epileptic seizures were recorded. According to the shape of EEG waves and the corresponding symptoms of the rats during their seizures, data of the four phases, referring to normal condition, preictal phase, ictal phase and postictal phases of epileptic seizures, were selected for nonlinear analysis. The variations of the ApEn and the correlation dimension were calculated.MAIN OUTCOME MEASURES: In the four phases of the seizures, before seizures, preictal phase, ictal phase and postictal phases, the changes in the ApEn and correlation dimension were observed.RESULTS: All the 6 rats entered the statistical procedure. During epilepsy, the ApEn and correlation dimension of the EEG signal in ictal phases (0. 447 ±0. 126, 2. 166 ±0. 377) decreased significantly while those in preictal phases(0. 807 ±0. 182, 4. 773 ±0. 319) and postictal phases (1. 241 ±0. 125, 6. 042 ±0. 373) (t = -3. 984to 17. 902, P ＜0. 01). The ApEn and the correlation dimension of the EEG signal in preictal and ictal phases had significant difference with those observed under normal conditions (1.313 ± 0. 090, 6. 405 ± 0. 694) (t = -5. 228 to 12. 740, P ＜ 0. 01 ).CONCLUSION: The changes in ApEn and correlation dimension showed by nonlinear dynamical approach in this study reflect the characteristics of EEG signals in preictal time, ictal time and postictal timeof the epileptic seizures and the differences among them. Additionally, they also reveal the laws in the changes of the complex ictal EEG signal.

The culture of Magnetospirillum magneticum WM-1 depends on several control factors that have great effect on the magnetic cells concentration. Investigation into the optimal culture conditions needs a large number of experiments. So it is desirable to minimize the number of experiments and maximize the information gained from them. The orthogonal design of experiments and mathematical statistical method are considered as effective methods to optimize the culture condition of magnetotactic bacteria WM-1 for high magnetic cells concentration. The effects of the four factors, such as pH value of medium, oxygen concentration of gas phase in the serum bottle, C:C (mtartaric acid: msuccinic acid) ratio and NaNO3 concentration, are simultaneously investigated by only sixteen experiments through the orthogonal design L16(44) method. The optimal culture condition is obtained. At the optimal culture condition (pH 7.0, a oxygen concentration 4.0%, C: C (mtartaric acid: msuccinic acid) ratio 1:2 and NaNO3 100 mg l-1), the magnetic cells concentration is promoted to 6.5×107 cells ml-1, approximately 8.3% higher than that under the initial conditions. The pH value of medium is very important factor for magnetic cells concentration. It can be proved that the orthogonal design of experiment is of 90% confidence. The results from the hysteresis of WM-1 shows that Hc = 230 Oe, Ms = 0.9 emu/g dry wt. Cells,and Mr / Ms = 0.50.

Arachidonic acid is an essential fatty acid in human nutrition and a biogenetic precursor of the biologically active prostaglandins and leukotrienes. ?~5 desaturase catalyzes the ?~5 dehydrogenation of di-homo-?-linolenic acid to form arachidonic acid in biosynthetic pathway of arachidonic acid. Using real time PCR technology,the transcriptional expression levels of gene encoding ?5 desaturase in three Mortierella alpina strains M10,M6 and M23,and in different growth phase of high arachidonic acid yielding strain M6,were determined. Results showed that there was a distinct corelationship between mRNA transcript level of ?~5 desaturase gene and biosynthesis of arachidonic acid. Results indicated that ?~5 desaturase plays an important role in arachidonic acid biosynthesis.

Objective To optimize the extraction technology of Zhiqian Capsule;To provide evidence for researches on preparation into new Chinese medicine. Methods The main influential factors of extraction technology included the quantity of water, extraction time and immersion time. The extraction effect was evaluated with the content of aesculetin and the extract yield as indexes. The optimal extraction technology of Zhiqian Capsule was selected by single factor experiment and central composite design-response surface method. Results The best extraction conditions were as follows:reflux extraction for twice, the first time adding 10-fold of water and extraction for 2.5 h, the second time adding 8-fold of water and extraction for 2 h. Conclusion The optimal extraction technology of Zhiqian Capsule is efficient for extracting aesculetin, as well as economical, reasonable, easy and feasible.

Purpose To evaluate the application value of volume CT perfusion (CTP) protocol with 128-slice CT scanner in patients with unilateral middle cerebral artery (MCA) stenosis or occlusion.Materials and Methods Thirty-five patients with severe unilateral MCA stenosis or occlusion who underwent cerebral volume CTP examination in Wuhan No.1 Hospital between July 2013 and December 2014 were evaluated.The volume CTP parameter maps of cerebral blood flow (CBF),cerebral blood volume (CBV),mean transit time (MTT) and time to peak (TTP) were analyzed.Meanwhile,the dynamic CT angiography (4D-CTA) images were obtained.Results In three patients,CBF,CBV and MTT were observed normal but TTP was delayed.In the other thirty-two patients,CBF in the affected side was lower than that in the contralateral side (but difference without significance:P＞0.05).The increased CBV,prolonged TTP and MTT were also detected in the affected side compared with the contralateral side (difference with significance:P＜0.05).McNemar test showed 4D-CTA and DSA diagnosis of middle cerebral artery occlusion were not significantly different (P＞0.05),and they had better consistency (Kappa=0.861,P＜0.05).Conclusion Brain volume CTP protocol with 128-slice CT scanner provides valuable information about cerebral artery abnormalities and hemodynamic changes in patients with severe stenosis or occlusion of MCA.It has great value for clinical application.

BACKGROUND:Traditional bone cement in the treatment of osteoporotic vertebral compression fracture easily induces heat dissipation effect, leakage, big difference in mechanical strength with the surrounding tissue, which greatly affects treatment effect of osteoporotic vertebral compression fracture. This prospective self-controled open-label clinical trial is designed to analyze the effectiveness of a novel high viscosity bone cement for osteoporotic vertebral compression fractures.
METHODS/DESIGN:This prospective self-controled open-label clinical trial wil be performed in the Yixing Hospital Affiliated to Jiangsu University of China. High viscosity bone cement wil be implanted in patients with osteoporotic vertebral compression fractures by percutaneous vertebroplasty. Immediate outcomes: Pain symptom of patients before and after implantation of high viscosity bone cement, and Visual Analogue Scale score. Middle- and long-term outcomes: The recovery of spinal function, Oswestry dysfunction index questionnaire, vertebral body height, bone cement leakage rate, Barthel index and SF-36 quality of life scale score.
DISCUSSION: This trial wil provide a clinical basis for the treatment of osteoporotic vertebral compression fractures with high viscosity bone cement.
ETHICS APPROVAL: This trial has been approved by the Medical Ethics Committee, Yixing Hospital Affiliated to Jiangsu University (Approval number 0136). Patients and their family members have signed the informed consent.

Objective To investigate the endoscopic and ultrasonic endoscopic features of colorectal carcinoid and the indications of endoscopic treatment. Methods The clinical data of 22 patients with colorectal carcinoid who had been admitted to our hospital from 2002 to 2007 were collected. The endoscopic and ultrasonic endoscopic features and the relationship between the features and invasion depth of colorectal carcinoid were analyzed. Results Under the endoscope, early carcinoid presented submucosa tumor with 1.5cm in diameter, and yellow or white smooth surface; advanced carcinoid presented submucosa tumor with 0.8-3.0cm in diameter, and yellow or white little nodus or ulcerative surface. The ultrasonic endoscopic feature of the colorectal carcinoid was orbicular-ovate low level echo tumor with punctiform slightly high-level echo and an unsharpness edge. Sixteen mucosal layer-cancers and submucosal layer-cancers were removed by endoscopic mucosal resection, and 10 of them were additional treated by argon plasma coagulation. After a follow-up period of 4-36 months, no recurrence was observed. Conclusions Endoscopy and endoscopic ultrasonography are effective methods to diagnose colorectal carcinoid and its invasion depth. Endoscopic treatment is a simple, safe and effective means to treat the early colorectal carcinoid tumors.

Objective To evaluate the role of Janus kinase 2-signal transducer and activator of transcription 3 (JAK2-STAT3) signaling pathway in sevoflurane postconditioning-induced inhibition of mitochondrial permeability transition pore (mPTP) opening during myocardial ischemia-reperfusion (I/R)in rats.Methods Sixty pathogen-free healthy male Sprague-Dawley rats,weighing 250-300 g,were divided into 4 groups (n=15 each) using a random number table:I/R group,sevoflurane postconditioning group (group SP),AG-490 group (group AG) and sevoflurane postconditioning plus AG-490 group (group SP+AG).Myocardial I/R was induced by 30 min ligation of the left anterior descending branch of coronary artery followed by 120 min reperfusion.In group SP,2.8％ sevoflurane was inhaled for 15 min starting from 2 min before reperfusion.JAK2 inhibitor AG-490 3 mg/kg was intravenously injected at 10 min before reperfusion in group AG.In group SP+AG,AG-490 3 mg/kg was intravenously injected at 10 min before reperfusion,and 2.8％ sevoflurane was inhaled for 15 min starting from 2 min before reperfusion.At 15 min of reperfusion,5 rats were sacrificed and myocardial specimens were obtained for determination of the expression of JAK2,phosphorylated JAK2 (p-JAK2),STAT3 and phosphorylated STAT3 (p-STAT3)in myocardial tissues by Western blot.The ratios of p-JAK2 to JAK2 expression (p-JAK2/JAK2) and pSTAT3 to STAT3 expression (p-STAT3/STAT3) were calculated.Five rats were sacrificed at the end of reperfusion for measurement of myocardial infarct size.The left 5 rats were selected and sacrificed,myocardial specimens were obtained,and the opening of mPTP was detected by a calcein-cobalt quenching method.Results Compared with group I/R,the myocardial infarct size and mPTP opening were significantly decreased,and JAK2/p-JAK2 and STAT3/p-STAT3 were increased in group SP (P＜0.05),and no significant change was found in the parameters mentioned above in SP+AG and AG groups (P＞0.05).Compared with group SP,the myocardial infarct size was significantly enlarged,the extent of mnPTP opening was aggravated,and JAK2/p-JAK2 and STAT3/p-STAT3 were decreased in SP+AG and AG groups (P＜0.05).Conclusion The mechanism by which sevoflurane postconditioning inhibits the opening of mPTP during myocardial I/R is related to activation of JAK2-STAT3 signaling pathway in rats.

Objective To Investigate the influence of high-intensity pulsed electromagnetic field (HIPEMF) on neural differentiation of neonatal rats neural stem cells in vitro.Methods Neural stem cells (NSCs) were isolated from the subventricular zone of 3-day-old neonatal rats and cultured with serum-free condition medium for 14 days.All the NSCs were then randomly classified into an experimental group which received the stimulation of HIPEMF (0.1 Hz,4 T,8 pulses) and a control group which received no special intervention.Differentiation of the culture was induced by addition of 10％ fetal bovine serum on the first day after intervention,the morphological changes of cells were observed under the microscope at different time points.The NSCs adhered to the wall and differentiated for seven days,the immunofluorescence was employed to observed and calculate the ratio of differentiated cells with astrocyte marker GFAP or neuronal markers TUJ1.RT-PCR and western blotting were used to measure the expression levels of the differentiated cells based on gene and protein levels,respectively.Results Immunofluorescence staining showed the number of TUJI positive cells in the experimental group(33.4％ ± 5.1％)was significantly more than the control group (26.5％ ± 7.0％),while the number of GFAP positive cells was decreased(23.9％ ± 5.0％) as compared with the control group(36.2％ ± 2.2％).RT-PCR showed that the TUJ1 mRNA expression levels in the experimental group was (1.682 ± 0.086) times of the control group.Western blot showed that the expression of TUJ1 (0.729 ±0.061) in the experimental group was higher than in the control group (0.590 ± 0.157),while the expression of GFAP in the experimental group (0.566 ± 0.056) was less than in the control group(1.034 ± 0.051).Conclusions HIPEMF facilitates differentiation of neural stem cells to neurons,at the cost of reducing astrocytic differentiation.

Objective Routine perioperative intravenous antimicrobial agents,was administered as surgical prophylaxis.However,whether balanced ultrafiltration during extracorporeal circulation can remove antimicrobial agent remains unclear.The concentrations of antimicrobial agent in plasma and ultrafiltrate samples were measured in this pseudo-extracorporeal circulation model.Methods Extracorporeal circulation consisted of cardiotomy reservoir (Ningbo Fly Medical Healthcare CO.,LTD.Ningbo,China),D902 Lilliput 2 membrane oxygenator (Sorin Group Asia Pte Ltd,Beijing,China) and Capiox (R) AF02 pediatric arterial line filter (Terumo Corporation,Beijing,China).HEMOCONCENTRATOR BC 20 plus (MAQUET Cardiopulmonary AG,Hirrlingen,Germany) was placed between arterial purge line and oxygenator venous reservoir.Fresh donor human whole blood was added into the circuit and mixed with Ringer's solution to obtain a final hematocrit of 24％-28 ％.After 30 minutes of extracorporeal circulation,zero-balanced ultrafiltration was initiated and arterial line pressure was maintained at approximately 100 mm Hg(1 mm Hg =0.133 kPa) with Hoffman clamp.The rate of ultrafiltration (12 ml/min) was controlled by ultrafiltrate outlet pressure.Identical volume of plasmaslyte A was dripped into the circuit to maintain stable hematocrit during 45 minutes of experiment.Plasma and ultrafiltrate samples were drawn every 5 minutes and concentrations of antimicrobial agent (including Cefmetasole and cefotiam) were measured with high performance liquid chromatography.Results All these two antimicrobial agents were detected in ultrafiltrate,demonstrating hemoconcentration may remove antimicrobial agent.The concentration of plasma antimicrobial agent decreased lineally with the increase of ultrafiltrate volume.At end of balanced ultrafiltration,the concentration of plasma cefotiam was (104.96 ± 44.36) μg/ml,which is about (44.38 ± 7.42) ％ of the initial concentration (238.95 ± 101.12) μg/ml; the concentration of plasma cefmetazole decreased linearly to (25.76 ± 14.78) μg/ml,which is about (49.69 ± 10.49) ％ of the initial concentration (51.49 ± 28.03) μg/ml.The total amount of cefotiam in ultrafiltrate is (27.16 ± 12.17)％ of the total dose administered,whereas cefmetasole in ultrafiltrate is (7.74 ±4.17)％.Conclusion Balanced ultrafiltration may remove antimicrobial agent from serum and has significant influence on plasma concentration of antimicrobial agent.The strategy of surgical prophylaxis should consider this unique technique during extracorporeal circulation.