Objective To study the histocompatibility of domestic new type nitinol alloy ventricular septal defect(VSD) occluder in order to test the feasibility for clinical application.Methods The domestic new type nitinol alloy VSD occluder was inserted into 20 healthy dogs with intravenous balanced anesthesia and tracheal intubation,assisted by animal breathing machine respiration.The dogs were given oral antibiotic and would be killed in several months after operation.According to different slaughter time(1,2,3,6 months),they were divided into 4 sections and including 5 dogs in each section.The occluder sites,the intimal coverage and the change of inflammatory cells were observed through gross anatomy,with the help of the light microscope and electron microscope.SPSS 11.0 software was used to analyze the data.Results The thickness of the endocardial enhanced with the time(P

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.

Objective To investigate the protective effect of c-jun N-terminal kinase (JNK)inhibitor SP600125 against acute liver failure in mice.Methods Fifty-five male C57/BL6 mice were divided into control group (n =30) and SP600125 group (n =25).The animals were given an intraperitoneal injection of D-galactosamine (D-GalN,400 mg/kg body weight)/lipopolysaccharide (LPS,30 μg/kg body weight).The control group and SP600125 group were given 10％ dimethyl sulfoxide (15 mL/kg body weight) or SP600125 (75 mg/kg body weight) subcutaneously 12 h and 1 h before D-GalN/LPS administration,respectively.D GalN/LPS induced mouse JNK activation was detected by immunohistochemistry for phospho JNK (p-JNK).D-GalN/LPS induced mouse liver cell apoptosis was detected by immunohistochemistry for Caspase-3 and TdT-mediated-dUTP nick endlabeling (TUNEL).Serum alanine transaminase (ALT) level was tested to assess liver injury.Survival rate of mice within 24 h after D-GalN/LPS administration was observed.The comparison between groups was done by t test and survival rate was analyzed by Kaplan-Meier method.Results JNK activity in liver tissues,as indicated by observation of p-JNK positive cells by immunohistochemistry,was diminished 4 h after D-GalN/LPS administration in SP600125 group.Reduced Caspase-3 activity was observed 6 h after D-GalN/LPS administration in SP600125 group (as indicated in immunohistochemistry by Caspase-3 positive cells).Mice in SP600125 group showed significantly lower TUNEL-positive cell count than control group (43.0±24.5 vs 194.7±73.8; t=9.743,P=0.000).Serum ALT level 6 h after D-GalN/LPS administration was (24.0±54.7) U/L in SP600125 group,which was significantly lower than that in control group [(1234.4±478.4) U/L; t=4.734,P=0.0015].SP600125 also significantly improved the survival rate within 24 h after D-GalN/LPS administration (4/5 vs 1/10； x2=5.225,P=0.0223).Conclusions JNK inhibitor SP600125 exerts protective effects against D-GalN/LPS induced acute liver failure in mice by suppressing JNK activation and hepatocyte apoptosis.

Effect and safety of repeated embryo aspiration for reduction of muhifetal cervical pregnancy Was retrospectively evaluated.Three women with muhifetal cervical pregnancy successfully received conservative treatment of repeated embryo aspiration under the guidance of transvaginal ultrasound,and the gestational sac contents were aspirated completely.Local(2.5～5.0 mg injectable methotrexate,MTX) or systemic medication was used.Our findings showed that repeated embryo aspiration for reduction of cervical multifetal pregnancy could improve the coupe of disease,decrease systemic medication of MTX,and discontinue a cervical pregnancy within 8 weeks effectively and safely.However,the mminimum therapeutic dose of MTX remained to be explored.

Animals ; Camptothecin ; pharmacology ; Liver Neoplasms, Experimental ; immunology ; Mice ; Neoplasm Transplantation ; Sarcoma, Experimental ; immunology ; Transplantation, Isogeneic

Disasters ; Earthquakes ; Emergency Medical Services ; manpower ; organization & administration ; Liability, Legal ; Public Health Practice

Objective To observe the effect of S-band micro-wave long-term intermittent irradiation on endocrine function in rats.Methods A total of 192 rats (male and female) were randomly divided into the sham-irradiation (normal control) groups and the irradiation groups.The irradiation groups were exposed with micro-wave at 3 dosages of 4,10 and 20 mW/cm2 for 6 min twice a week for 12 weeks,while no administration was given to control group.The endocrine parameters in blood serum were examined by radioimmunoassay at 4,8,12 week during irradiation and 4 week post-irradiation.Results After the irradiation of S-band microwave,parts of the endocrine parameters changed.T3 in famale rats decreased at first and then increased,especially in 10 mW/cm2 group at 8 and 12 week,20 mW/cm2 group at 4 and 12week(t =-2.586,-2.642,-5.075,-4.365,P <0.05).FT3 in famale rats had the similar trend asT3,significantly lower in 4 and 10 mW/cm2 groups than that in the control group at 4 week (t = 2.275,2.510,P <0.05),then increased,especially in three irradiation groups at 12 week (t =-2.636,-2.851,-5.240,P < 0.05).TSH decreased at 4 week,especially in 10 mW/cm2 group (t = 2.300,P < 0.05) ; and then increased in the irradiation groups at 20 mW/cm2 at 8 and 12 week (t =-2.838,-3.651,P <0.05).COR and ACTH in male rats showed changes in volatility,in which the 4,10 and 20 mW/cm2 groups at 8 week increased significantly (t =-2.772,-2.234,-2.505,P < 0.05),while 20 mW/cm2 group at 12 week decreased significantly (t=3.067,P < 0.05).E2 in female rats was slightly lower in irradiation groups at 4 week than the control group,then increased,especially in 10 mW/cm2 group at 8 week,three irradiation groups at 12 week (t =-2.322,-3.179,-2.655,-4.716,P < 0.05),and returned to the normal at 4 week post-irradiation,significantly lower in 4 mW/cm2 group than that in the control group (t = 2.250,P < 0.05).T in male rats increased first and then decreased,especially in 10 mW/cm2 group at 8 week(t =-2.435,P < 0.05).After exposure the above indexes restored to some extent.Conclusions The long-term intermittent irradiation of S-band microwave can cause adverse effects on the endocrine function of rats.

Objective To study the effects of Pervanadate(Per) on BET-2 cells cell cycle arrest and apoptosis induced by ionizing radiation. Methods The BET-2 cells were radiated with 0, 1, 3, 5, 7, 10 Gy and divided into PTP(protein tyrosine phosphatases)-specific inhibitor Per-treated group and non-pervanadate group(served as a control) and then incubated after ?-ray irradiation. Cell cycle and apoptosis were measured by FCM and Hematoxylin-Eosin staining at different time phases. Results G2/M phase arrest and apoptosis were induced in a pattern of dose-effect and time-course after irradiation in the BET-2 cells. In Per-treated group, G2/M phase arrest increased more notably, and apoptosis decreased markedly. Conclusions These studies suggested that Pervanadate potentialy enhance the ratio and prolong the term of G2/M phase arrest, and facilitate the damaged hematopoietic cells to be repaired, remarkably prevent radiated-cells from apoptosis.

Objective To investigate the effects of cinnamaldehyde and citral on DNA and RNA of Aspergillus flavus and A. fumigatus cells and their mechanisms. Methods A. flavus and A. fumigatus were incubated on Czapeks agar plate (treated with cinnamaldehyde and citral at different concentrations) at 26.5 ℃ for 3—6 d. The normal and treated cells were observed by laser scanning confocal microscope (LSCM) and image analysis to describe the DNA and RNA levels by quantity and localization. Results DNA and RNA levels were changed greatly and multinucleate coniospores appeared in the treated cells. Conclusion Cinnamaldehyde and citral have directly or indirectly interfered the conventional synthesis of fungal hereditary DNA and RNA and normal differentiation of conidiophore in A. flavus and A. fumigatus, thus inhibiting the normal cell cycle and the growth and propagation of fungi.