In order to improve the reliability of cardiac pacemaker contact-less power supply technology, this paper proposes a novel application of wireless feedback voltage stabilizing technology to adjust heart disease patients with inner power supply filter circuit output voltage and current control method, to keep the output voltage stability, and to ensure that the super capacitor and cardiac pacemaker to get a stable power supply. To implement the real-time accurate voltage control with considering the primary and secondary side inductance coupling coefficient changes, the change of the external power supply voltage and load, it is necessary to test thee real-time and accurate output voltage and current value after rectifying filtering. Therefore, based on the chaotic control theory, we adopted method of phase diagram on the basis of the quick observation after rectifying filtering, so that the method of voltage and current could improve the detection time of the circuit. The phase diagram of proposed control method can be divided into 8 segments, and we got 7 zero-extreme points. When these zero-extreme points are detected, according to extreme points of the zero instantaneous values, the corresponding average values of voltage and current were obtained. Simulation and experimental results showed that using the above method can shorten the response time to less than switch devices 1/2 switching cycles, thus validating the effectiveness and feasibility of the proposed detection algorithm.
Algorithms ; Electric Power Supplies ; Feedback ; Humans ; Nonlinear Dynamics ; Pacemaker, Artificial ; Wireless Technology

The isolated vessel elements from the xylem in Chinese Sarcandra species were observed by scanning electron microscope and optical microscope. The vessel elements with simple pits or (and) bor dered pits or (and) scalariform pits or (and) circular-scalariform pits in their secondary walls are 1200-1900 in length and all have scalariform multiperforation plates in which the numbers of bars are between 60 to 160.

Objective:To display human CD137 extra-cellular domain on phage using phage display technique and detect its antigenicity and bioactivity.Methods:CD137 extra-cellular gene was amplified from CIS plasmid using PCR and then clone it into pComb3HSS.The recombinant pComb3H-CD137 was transfected into competent bacteria XL1-Blue, then the transfected bacteria was co-infected with help phage VCSM13 and CD137 extra-cellular domain was displayed on the phage surface. The antigenicity and bioactivity of CD137 displayed on phage was detected by ELISA and inhibition assay of lymphocyte proliferation(MTT).Results:CD137 PCR products was 525 bp, the recombined plasmid was named pComb3H-CD137, CD137 was displayed on phage. ELISA detection showed that phage displayed CD137 possesses antigenicity of human CD137. MTT inhibition assay showed that lymphocytes proliferation stimulated by PHA and CD137 could be inhibited by phage displayed CD137, indicating that it has bioactivity of nature CD137.Conclusion:The studies demonstrate that phage display system can display human CD137 extra-cellular domain homodimer with antigenicity and bioactivity.

ObjectiveContrast research the operative effect of the pulmonary artery banding (PAB) in the congenital heart disease with pulmonary artery hypertension,underwent the single ventricle repair procedure in different age.Methods 49 cases,male 31 and female 18.Age (7.8 ± 3.8 ) years old,weight ( 8.82 ± 4.24) kg,percutaneous blood oxygen saturation ( SPO2 ) 0.90 ± 0.04,preoperative mean pulmonary artery pressure (mPAP) ( 54.6 ± 16.8 ) mm Hg.single ventricle 13cases,tricuspid atresia 12 cases,double outlet of right ventricle with left ventricular dysplasia 11 cases,tricuspid stenosis 5 cases,ventricular imbalance type complete atrioventricular canal defect 5 cases and cross heart cases 3 cases.divided into three groups:≤0.5 years old of 17 cases,0.5 to 2.0 years old of 17 cases,≥2.0 years old 15 cases.All cases taken PAB under anesthesia and cpb,inhaled oxygen concentration 40％,SPO2 0.85,MPAP 20 mmHg.comparatively analysis postoperative SPO2,MPAP,Ventilator using time,ICU stay time and operation mortality of the three groups.ResultsThe postoperative PAP obviously decreased.Three groups of postoperative SPO2,mPAP,ventilator using time,ICU stay time were not significantly different.More than were followed up 6-72 months,1 cases ( 1-2 months) dead in aspiration two months postoperation.the other three cases had been completed Glenn and/or Fontan.ConclusionPAB can effectively reduce the pulmonary artery pressure in the different age children with congenital heart disease and pulmonary artery hypertension,the effect is good.more than 2 years old children still PAB feasible operation,and likely to complete the Glenn and/or Fontan procedure.

Immunogenicity for medical devices of animal origin is the key and difficult point during immune safety evaluation for these devices. This paper firstly investigated the effect of collagen sponge of animal origin on mouse splenic lymphocyte transformation and proliferation, and then analyzed the influence factors on the MTT method and CFSE method. The results showed that collagen sponge extract cannot significantly induce transformation and proliferation of mouse splenic lymphocyte in vitro.
Animals ; Cells, Cultured ; Collagen ; pharmacology ; Lymphocyte Activation ; drug effects ; Mice ; Porifera ; chemistry ; Spleen ; cytology

To discuss IC50 application in cytotoxicity tests of medical devices, we firstly investigated the vibrating condition and endpoint of MTT method specified in ISO 10993-5: 2009. Furthermore, we demonstrated the application of IC50 in the result evaluation of MTT method. The experimental results show that usage of IC50 in quantitative evaluation of MTT method is feasible.
Equipment and Supplies ; adverse effects ; standards ; Inhibitory Concentration 50 ; Toxicity Tests ; methods

[Abstract ] Objective Liver cirrhosis modeling with carbon tetrachloride (CCL4) may be influenced by many factors, such as drug concentration and dosing methods.In this article, we explored the influences of different concentrations and different dosing methods and time of CCL4 on the induction of liver cirrhosis in rats. Methods We constructed rat models of liver cirrhosis with different con-centrations of CCL4(30%and 50%), using different dosing methods (subcutaneous injection, intraperitoneal injection, and intragastric administration) , and for different lengths of dosing time (8 wk, 10 wk, and 12 wk) .We collected blood and liver tissues from the rats at different time points for HE and MTC staining, biochemical and histomorphological scores based on the Scoring Model for Liver Cirrho-sis Disease (SLCD, expressed by R) and the Laennec Fibrosis Scoring System (LFSS, expressed by L), and analysis of the results by 3 ×2 ×3 factorial experiment design. Results The R value was lower in the intraperitoneal injection than in the subcutaneous injection and intragastric administration groups, and so was it in the 50% than in the 30%CCL4 group, decreasing with the extending of dosing time, with statistically significant differences in the main effects ( P<0.05) as well as a remarkable correlation among drug concentrations, dosing methods, and dosing time (P<0.05).The L value was higher in the intraperitoneal injection than in the subcutaneous injection and intra-gastric administration groups, and so was it in the 50% than in the 30% CCL4 group and in the 12 wk than in the 10 wk and 8 wk groups, with statistically significant differences in the main effects ( P<0.05) but no remarkable correlation among drug concentrations, dosing methods, and dosing time ( P>0.05) .The death rate showed an increasing trend in the intraperitoneal injection, subcutaneous injection and intragastric administration of 30% CCL4 (25.33%, 37.78%, and 38.37%) and 50% CCL4 (42.97%, 47.85%, and 51.88%), higher in the 50%than in the 30%CCL4 .However, no significant differences were found in the survival curves among differ-ent dosing methods or between different drug concentrations (P>0.05). Conclusion Intraperitoneal injection was better than subcu-taneous injection and intragastric administration of CCL4 in inducing liver cirrhosis, and the three dosing methods all showed progressively improved efficiency of modeling with the increase of drug concentration and dosing time.

Objective To discuss the safety,efficacy and time window of thombolysis using recombinant staphylokinase(r-Sak).Methods The model of acute cerebral infarction was established with interventional embolization technique in 24 adult beagle dogs,which were randomly divided into 3 groups including control group,6 h intra-arterial group and 3 h intravenous group.Angiography was performed before thrombolysis.We administered r-Sak for thrombolysis(10 ml of saline in control group,0.2 mg/kg of r-Sak in the intra-arterial group through left internal carotid artery 6 h after embolization,and 0.2 mg/kg of r-Sak in the intravenous group through femoral vein 3 h after embolization).Follow-up angiography was repeated half,1 and 2 hours after thrombolysis.The plasma levels of PT,APTT and D-dimer were assayed at the time points of 30 min before thrombolysis,30 min,60 min and 120 min after thrombolysis.These canines were sacrificed,and their brains were taken out for pathological study at 24 hours after embolization.Results The recanaled vessels at 2 hours after thrombolysis was 11(11/13) in the intra-arterial group,8(8/11) in r-Sak intravenous group and 1(1/10) in control group,and the vessels of complete recanalization was 6(6/13),2(2/11) and 0(0/10),respectively.There were statistically significant differences among the three groups (P=0.001 and P=0.035 respectively),but there were no statistically significant differences between the intra-arterial and the intravenous groups (P=0.630 and P=0.211).The PT and APTT are significantly prolonged in the thrombolytic groups.The levels of D-dimer was not changed after thrombolysis (P＞0.05). All dogs were alive 24 h ours after embolization.The clinical presentations in the thrombolytic groups were better.Pathologically,there were no cerebral hemorrhage in all groups.Conclusion r-Sak has strong effect of thrombolysis,and its complication of intracerebral hemorrhage is rare.The intra-arterial thrombolysis 6 h after embolization using r-Sak is safe and effective.

Objective To analyze and summarize the applicative experience and operative effective of the diaguostictreatment-repair strategy in the transpossion of great arteries(TGA) infants with ventricular septal defect and severe pulmonary hypertension more than 6 months.Methods From January 2010 to October 2011,17 TGA cases with ventricular septal defect and severe pulmonary hypertension.There were 13 male and 4 female.≥0.5-＜ 1.0 years old 6 cases,≥ 1.0-＜ 3.0 years old 3,≥3.0 years old 8 cases.Combine anomalies: patent ductus arteriosus in 6 cases,atrial septal defect in 5 cases,valve insufficency in 2 cases.All preoperative cases were performed echocardiography,right-sided heart catheterization 3 cases,coronary CT examinationll cases.After diagnostic-treatment 2-4 weeks,all cases performed arterial switch operation under compound intravenous and inhaled anesthesia.Results No operative death.After diagnotic-treatment,SPO2 improved 10％-21％,and mPAP decreased 10-20 mm Hg.Follow-up 11.2 (6,20) months,one dead.Postoperative residual pulmonary arterial hypertension in 35.29％,6/17cases,all of them were ≥3 years old.Continue to pulmonary arterial hypertension targeted drugs treatment for 6-20 months later,pulmonary artery pressure decreased obviously.Conclusion The TGA infants with ventricular septal defect pulmonary arterial hypertension more than 6 months,can be selectively performed arterial switch operation under went diagnostic-treatment-repair strategy,continue to pulmonary arterial hypertension targeted drug therapy postoperation,the effect is good.

This is a study on the cultivation condition in vitro and differentiation of neural stem cells from human embryonic brain in order to find a way to get purified multipotential neural stem cells. The single cells was derived from the three-month embryonic brain digested with trypsin, some cells was frozen, the other cells were expanded with EGF and bFGF, the single-cell-clone was obtained by the way of limited dilution, and the serum was used to induce the cells differentiation. The cells were detected with the method of immunohistochemistry. The results showed that a lot of neurospheres could be seen in the presence of mitogens (both EGF and bFGF) and serum could induce neural stem cells to differentiate into neurons, astrocytes, and oligodendrocytes. These indicate that the survival and proliferation of neural stem cells rely on the cooperation of EGF and bFGF. The neural stem cells can also be harvested from the frozen cells.
Astrocytes ; cytology ; Brain ; cytology ; embryology ; Cell Differentiation ; Cells, Cultured ; Culture Media ; chemistry ; Epidermal Growth Factor ; chemistry ; Fibroblast Growth Factor 2 ; chemistry ; Humans ; Immunohistochemistry ; Neural Stem Cells ; cytology ; Neurons ; cytology ; Oligodendroglia ; Pluripotent Stem Cells ; cytology