Effect and mechanism of different ways of transplanting bone marrow mesenchymal stem cells in cardiopulmonary resuscitation in rats.

The effect and mechanism of different ways of transplanting bone marrow mesenchymal stem cells (MSCs) were explored for treating cardiopulmonary resuscitation in a rat model. Rats were divided into the cardiopulmonary resuscitation group (Group Con), the stereotactic lateral ventricle transplantation group (Group LV), the internal carotid artery transplantation group (Group A), and the femoral vein transplantation group (Group V). MSCs were transplanted in Groups LV, A, and V. The MSC transplantation groups had a significantly higher neurological score than Group Con on days 3 and 7 after recovery (P < 0.05), and the Group LV score was the highest in all groups (P < 0.05). On day 3 after recovery, the MSC count of Group LV was significantly higher than those of Groups A and V (P < 0.01). On day 7 after recovery, the MSC count in the hippocampus of Group LV was significantly higher than those of Groups A and V (P < 0.05). On day 3 after recovery, the S100B level of Group LV was significantly lower than those of Groups A and V (P < 0.05). On day 7 after recovery, the S100B level was not significantly different between the MSC transplantation groups (P > 0.05). The expressions of vascular endothelial growth factor and brain-derived neurotrophic factor did increased significantly in the MSC transplantation groups on day 7 after recovery, particularly Group LV. Therefore, MSC therapy could significantly improve nerve function after cardiopulmonary resuscitation, and stereotactic lateral ventricle injection transplantation is an optimal method.

Superposed pulse amplitude modulation for visible light communication.

We propose and experimentally demonstrate a novel modulation scheme called superposed pulse amplitude modulation (SPAM) which is low-cost, insensitive to non-linearity of light emitting diode (LED). Multiple optical pulses transmit parallelly from different spatial position in the LED array and overlap linearly in free space to realize SPAM. With LED arrangement, the experimental results show that using the modulation we proposed the data rate of 120 Mbit/s with BER 1 × 10(-3) can be achieved with an optical blue filter and RC post-equalization.

Optimization of preparative conditions for poly-DL-lactide- polyethylene glycol microspheres with entrapped Vibrio cholera antigens.

Poly-dl-lactide-polyethylene glycol (PELA) with different contents of polyethylene glycol(PEG) were synthesized and the PEG content was estimated according to the integral height of hydrogen shown in 1H-NMR. PELA microspheres containing V. cholera antigen, outer membrane protein (OMP) were prepared by a water-in-oil-in-water (W/O/W) based on solvent evaporation procedure. Antigen microspheres with smooth surface, suitable size for oral administration (0.5-5 microm), high loading efficiency (about 60%) and low level of residual solvent (lower than 20ppm) were obtained. Microspheres prepared from PELA with PEG content of about 10% achieved the highest loading efficiency among PELA copolymers and poly-dl-lactide (PLA) homopolymer, which suggested that microspheres size, morphology and the precipitation rate of polymer showed considerable relations with OMP loading efficiency. The regulation of the solvent components of the oil phase contributes to a stable emulsion W/O, and it is concluded that the stable emulsion W/O plays a significant role in improving the protein loading efficiency of obtained microspheres. The addition of stabilizer, such as gelatin and polyvinyl alcohol, into the internal water phase before emulsification produced no significant difference in OMP entrapment and microspheres size. A higher OMP loading efficiency was achieved by adding NaCl or adjusting the pH at the iso-electric point of OMP in the external water phase. It was indicated in vitro that PELA microspheres with smaller size showed larger extent of initial release and higher release rate, whereas microspheres with the diameter of 2.17 microm showed no apparent burst effect.

Highly stereoselective alpha-O-glucosylation of heterocyclic ketene aminals.

A new series of alpha-glucosides of heterocyclic ketene animals have been synthesized. The double bonds of the glucosides resulted in Z or E configuration by using CaH2 or a Lewis acid as catalyst, respectively. A special complex of mercuric cyanide with glucopyranosides was the result when Hg(CN)2 was used to catalyze the reaction.

Synthesis of O-glycopyranosyl heterocyclic ketene aminals and their use as glycosyl donors.

The synthesis and reactions of glycopyranosyl heterocyclic ketene aminals were investigated. Under mild conditions, the benzoyl-substituted heterocyclic ketene aminals 3 or 4 underwent O-glycosylation with tetra-O-acetyl-alpha-D-glucopyranosyl bromide (1) using mercuric cyanide or silver trifluoromethanesulfonate as catalyst in acetonitrile to give O-glycopyranosyl heterocyclic ketene aminals 5-7 and 8-11, respectively. The beta-anomers were the sole products. By the O-glycosylation of heterocyclic ketene aminals with 1, the O-attack of heterocyclic ketene aminals was carried out for the first time. Some of 5-11 in the synthesis of oligosaccharides 14 and 15 can provide a valuable leaving group at the anomeric position of the glycopyranosyl ring. Compounds 6c or 10c may be potentially useful as glycosyl donors in the synthesis of oligosaccharides.

Synthesis of glucosylated 1,2,3-triazole derivatives.

A series of potential bioactive compounds, 1-glucosyl-4-heterocyclyl-5-(p-substituted-phenyl)-1,2,3-triazoles , were synthesized. Highly stereoselective products were obtained in good yield. Primary activity screening showed that this type of N-glucosylic compound possessed antitumour and antiviral activities.

Ca,P-rich layer formed on high-strength bioactive glass-ceramic A-W.

Glass-ceramic A-W, containing crystalline apatite and wollastonite in a MgO-CaO-SiO2 glassy matrix shows high bioactivity as well as high mechanical strength, but other ceramics containing the same kinds of crystalline phases in different glassy matrices do not show the same bioactivity. In order to investigate the bone-bonding mechanism of this type of glass-ceramic, surface structural changes of the glass-ceramics after exposure to simulated body fluid were analyzed with various techniques. A solution with ion concentrations which are almost equal to those of the human blood plasma was used as the simulated body fluid, instead of Tris-buffer solution hitherto used. For analyzing the surface structural changes, thin-film x-ray diffraction was used in addition to conventional techniques. It was found that a bioactive glass-ceramic forms a Ca, P-rich layer on its surface in the fluid but nonbioactive ones do not, and that the Ca, P-rich layer consists of carbonate-containing hydroxyapatite of small crystallites and/or defective structure. These findings were common to those of Bioglass-type glasses. So, we conclude that the essential condition for glass and glass-ceramic to bond to bone is the formation of the surface apatite layer in the body environment but it is not essential to contain apatite within the material. Bioactivity of glass and glass-ceramic can be evaluated in vitro by examining the formation of the surface apatite layer in the simulated body fluid described above.