Objective To prepare nifedipine (NP)skeleton frame sustained release tablets by adopting hydroxypropyl-beta-cy-clodextrin (HPC)and polyethylene glycol (PEG)as the matrix and to investigate its sustained release effect on NP.Methods NP skeleton frame sustained release tablets were prepared by the direct compression method after forming the inclusion complex with NP and HPC on a 1∶1 ratio and mixing with PEG.The in vitro drug release curves and the in vivo concentration-time curves of NP skeleton frame sustained release tablets were detected with the NP-PEG tablet without inclusion complex,NP-HPC tablet and NP powder capsule (NP capsule)as the control.Results The 5 h cumulative release rate of NP skeleton frame sustained release tablet in the simulated gastric fluid test(pH 1.2)was 36.4%,its sustained release effect was significantly stronger than that of the NP-HPC tablet group (80%,P<0.01)and the NP-PEG tablet group (100%,P<0.01).The in vivo test showed that AUC0-12 [(6 413±436)h/(ng·mL)],Cmax[(983±192)ng/mL]and tmax[(5.7±1.1)h]in the NP skeleton frame sustained release group were significantly higher than those in the NP-HPC tablet group,the NP-PEG tablet group and the NP Capsule group (all P<0.01 or 0.05).Conclusion NP skeleton frame sustained release tablets exhibits the sustained release effect on NP,can extend the NP in vitro release time,and improve the NP′s bioavailability,which is a novel NP sustained release tablet with excellent properties.

Brain computer interface is a control system between brain and outside devices by transforming electroencephalogram (EEG) signal. The brain computer interface system does not depend on the normal output pathways, such as peripheral nerve and muscle tissue, so it can provide a new way of the communication control for paralysis or nerve muscle damaged disabled persons. Steady state visual evoked potential (SSVEP) is one of non-invasive EEG signals, and it has been widely used in research in recent years. SSVEP is a kind of rhythmic brain activity simulated by continuous visual stimuli. SSVEP frequency is composed of a fixed visual stimulation frequency and its harmonic frequencies. The two-dimensional ensemble empirical mode decomposition (2D-EEMD) is an improved algorithm of the classical empirical mode decomposition (EMD) algorithm which extended the decomposition to two-dimensional direction. 2D-EEMD has been widely used in ocean hurricane, nuclear magnetic resonance imaging (MRI), Lena image and other related image processing fields. The present study shown in this paper initiatively applies 2D-EEMD to SSVEP. The decomposition, the 2-D picture of intrinsic mode function (IMF), can show the SSVEP frequency clearly. The SSVEP IMFs which had filtered noise and artifacts were mapped into the head picture to reflect the time changing trend of brain responding visual stimuli, and to reflect responding intension based on different brain regions. The results showed that the occipital region had the strongest response. Finally, this study used short-time Fourier transform (STFT) to detect SSVEP frequency of the 2D-EEMD reconstructed signal, and the accuracy rate increased by 16%.
Algorithms ; Brain ; physiology ; Brain Mapping ; Brain-Computer Interfaces ; Electroencephalography ; Evoked Potentials, Visual ; Humans ; Neural Pathways

Collagen (Coll), as the basic material of matrix scaffolds for cell growth, has been widely used in the field of tissue engineering and regenerative medicine. In this study, collagen protein was modified by L-lysine (Lys), and cross-linked by genipin (GN) to prepare the L-lysine-modified collagen (Lys-Coll-GN) scaffolds. Microstructure, pore size, porosity, stability and biocompatibility of Lys-Coll-GN scaffolds were observed. The results showed that the bond between L-lysine and collagen protein molecule was formed by generating amide linkage, and mouse embryo fibroblasts proliferation was not inhibited in the Lys-Coll-GN scaffolds. In the multiple comparisons of Coll-scaf- folds, Coll-GN scaffolds and Lys-Coll-GN scaffolds, Coll-scaffolds was the worst in mechanical characteristics while the highest in biodegradation rate. Compared to Coll-GN scaffolds, Lys-Coll-GN scaffolds had more fiber structure, higher interval porosity (P<0. 01). Although the tensile stress of Lys-Coll-GN scaffolds reduced significantly, its e- longation length extended when the scaffolds was fractured (P<0. 01). The percentage of Lys-Coll-GN scaffolds residual weight was lower than that of Coll-GN scaffolds after all the scaffolds were treated by collagenase for 5 days (P<0. 01). This study suggested that Lys-Coll-GN scaffold had good biocompatibility, and it improved the mechanical property and degradation velocity for collagen-based scaffold. This study gave a new predominant type of tissue engineering scaffold for the regenerative medicine.
Animals ; Biocompatible Materials ; chemistry ; Cell Proliferation ; Collagen ; chemistry ; Cross-Linking Reagents ; Fibroblasts ; cytology ; Iridoids ; chemistry ; Lysine ; chemistry ; Mice ; Porosity ; Tissue Engineering ; Tissue Scaffolds

Objective To explore the effects of hammerhead ribozyme on the expression and activity of NHE 1 and pHi in pulmonary artery smooth muscle cells (PASMCs) of rats and its role in PASMCs proliferation in vitro . Methods According to the secondary structure of NHE 1 mRNA in rats, NHE 1 specific hammerhead ribozyme was designed with the assistance of computer. The recombinant vector of retroviral plasmid pLXSN and hammerhead ribozyme, PRZ, was transfected into the cultured PASMCs. G418 resistant cell clones were screened with 100 ?g/ml G418. Then, the expression of NHE 1 mRNA was detected by RT PCR, intracellular pH(pHi) value and recovery rate of pHi after intracellular acid loading were measured by fluorescent probe BCECF. 22 Na uptake and 3H TdR incorporation were determined, respectively. Results Compared with the cells transfected with pLXSN and non transfected cells, NHE 1 mRNA, pHi value, pHi recovery rate, 22 Na uptake and 3H TdR incorporation decreased significantly in cells transfected with recombinant vector PRZ. No significance was found between the pLXSN transfected group and non transfected group. Conclusion Hammerhead ribozyme can cleave the target NHE 1 mRNA specifically, reduce the expression of NHE 1 mRNA, induce intracellular acidosis and consequently suppress the proliferation of PASMCs.

BACKGROUND:After acute myocardial infarction(AMI),there is still surviving myocardium in and around the infarcted area,which plays an important role in the occurrence of arrhythmia. OBJECTIVE:To study the alterations of the activities of Na+ channel current(INa),L-calcium current(ICa-L),transient outward K+ current(Ito) and inward rectifying K+ current(IK1) in the cardiomyocytes in the infarcted area after AMI. DESIGN: A randomized controlled study. SETTING:Department of Cardiology,Bethune International Peace Hospital. PARTICIPANTS:The experiment was finished in the Central Laboratory of the Department of Cardiology,Bethune International Peace Hospital from January to June 2003.Twenty New Zealand pure big-ear rabbits were randomly divided into AMI group(n=10) and control group(n=10). INTERVENTIONS:Rabbit AMI models were established by ligation of the left anterior descending coronary artery.The ventricular myocytes were separated with the method of enzymatic dissociation technique,and the changes of the ion currents were recorded with the whole cell patch-clamp techniques. MAIN OUTCOME MEASURES:The changes of INa,ICa-L,Ito and IK1 in the cardiomyocytes taken from the infarcted area of epicardium 24 hours after AMI in both the AMI and control groups. RESULTS:Twenty-four hours after AMI,the peak current densities of INa,ICa-L and IK1 in the AMI group [(28.48± 3.53) pA/pF,n=16;(3.91± 0.95) pA/pF,n=12;(26.93 ± 3.48) pA/pF,n=16]were all significantly reduced as compared with those in the control group [(45.50± 5.33) pA/pF,n=12;(5.58± 1.53) pA/pF,n=10;(34.12± 4.21) pA/pF,n=10] (t=3.026,P< 0.01;t=2.985,P< 0.01;t=2.706,P< 0.05).There was no significant difference in the Ito density between the AMI group and control group (P >0.05). CONCLUSION:The reduce of INa,ICa-L and IK1 caused by AMI can result in the decrease of myocardial conduction velocity,the shortening of action potential-time,abnormal repolarization,which is possibly the ionic mechanism for the reentrant ventricular arrhythmia after AMI.

This paper dealt with the influences of different media, temperature, light and pH to the amount of oospore formation. The results showed that millet agar, bai yun beau agar and soybean agar provided the favorable condition for oospore formation, the number of oospores was 131.6~149.6 /cm2, but a few oospores was formation on frozen pea agar. The results also suggested that the optimal conditions for oospore formation were 18℃, pH7 and darkness. The oospores failed to be formed tinder fluorescent or black light.

Traditional Chinese medicine is the crystallization of civilization and wisdom of Chinese nation , in which the complex components exhibit unique advantages in anti-tumor therapy through multi-channel and multi-target.Through the summary of the litera-tures recently, the research on anti-tumor mechanism of traditional Chinese medicine was reviewed to provide reference for the deep re -search and clinical application of traditional Chinese medicine .

BACKGROUND:Proximal femoral nail anti-rotation has good biomechanical basis, and has obvious advantages for intertrochanteric fracture in aged patients, but there are some problems in the clinic, because of improper handling of material matching and operation details, which can impact therapeutic effects and functional recovery. OBJECTIVE:To analyze the efficacy and issues of proximal femoral nail anti-rotation in the treatment of intertrochanteric fracture in patients at more than 60 years old. METHODS:From July 2011 to July 2012, proximal femoral nail anti-rotation was used to treat 56 cases of intertrochanteric fractures. Clinical data bank was established to analyze intraopeative problems and postoperative complications. At 1, 3, 6, 9 and 12 months postoperatively, outpatient and telephone folow-up were carried out to evaluate therapeutic effects and functional recovery of hip joint. RESULTS AND CONCLUSION:Four patients died within 1 year. Seven patients lost within a year for other reasons. The remaining 45 patients were folowed with the time from 12 to 24 months, with an average time of 18.2 months. Harris score was (85.00±6.75) points. There were excelent in 26 cases, good in 15 cases, average in 3 cases and poor in 1 case, with an excelent and good rate of 91%. 18 cases were not satisfied with the position of fracture fragments. In 9 cases, proximal femur was not match with the proximal femoral nail anti-rotation. Seven cases were not satisfied because of the location and length of the spiral blade. Seven cases affected lateral cortex fracture. One case experienced postoperative pulmonary embolism. One case suffered from cardiovascular and cerebrovascular diseases. Nine cases suffered from local sweling. 13 cases experienced hip pain. Five cases affected the healing of fracture extended. Results showed that proximal femoral nail anti-rotation for intertrochanteric fracture in aged patients obtained good outcomes, but we should improve the separation of fracture fragments and reduce intraoperative and postoperative complications.

AIM: To study the current density of transient outward potassium current (I_(to)) in cells from the epicardial zone of the 1-week and 2-month infarcted rabbit heart. METHODS: Rabbits were infarcted by ligation of the left anterior descending coronary artery, 1 week as well as 2 months later, the single ventricular myocytes were isolated enzymatically from the infracted area of 1-week infracted rabbit heart (PMI-1 week) and 2-month infracted heart (PMI-2 months), region remote from the infracted zone of 2-month infracted heart (REM-2 months) and free wall of left ventricule from noninfarcted heart (CON). I_(to) was recorded using whole cell patch-clamp techniques. (RESULTS:) Membrane capacitance of myocytes in REM-2 months group was signifitantly larger than that in CON. I_(to)current density (at +60 mV) was significantly reduced in PMI-1 week [(7.5?2.4) pA/pF, n=12] and PMI-2 months [(10.6?4.1) pA/pF, n=18] compared with CON [(17.4?5.2) pA/pF, n=16], P

AIM: To study the effect of experimental acute necrotizing pancreatitis (ANP) on sodium and L-type calcium current in rat cardiomyocytes. METHODS: I Na and I Ca-L were recorded using whole cell patch-clamp techniques from left ventricular myocytes in ANP model established by retrograde injection of 3 5% sodium taurocholate 2 5 mL/kg into pancreatic duct. RESULTS: Peak I Na current density (at -30 mV) was significantly reduced in ANP [(12 45?2 26) pA/pF, n =16] compared with sham [(25 32?3 31) pA/pF, n= 14], P