ObjectiveTo prepare recombinant human basic fibroblast growth factor (rhbFGF) loaded magnesium-poly(D,L-lactide-co-glycolide) (Mg-PLGA) stent and to evaluate its angiogenesis effect in rat model of hindlimb ischemia.MethodsThe stent was prepared with spiral magnesium (Mg) and loaded with therapeutic agent rhbFGF and PLGA matrix.In vitro drug release study was carried out and the effect was evaluated using a standard animal model of rat hindlimb ischemia.A mechanical drill was conducted and the stent was implanted.The concentrations of Mg2+ in the muscle adjacent to the stent,rat plasma,urine and stools of the experimental animals were tested to analyze the degradation and metabolism of metal Mg.Immunohistochemical staining was performed to evaluate the angiogenesis effect of the stent.ResultsThe drug loaded in the stent could release continuously for about 4 weeks.The concentrations of Mg2+ in the rat plasma,urine and stools were within normal range.Immunohistochemical and quantitative analysis showed that the effect of Mg-PLGA-rhbFGF stent on angiogenesis of rat limb ischemia was better than that of the control group.ConclusionRhbFGF loaded MgPLGA stent could promote angiogenesis of rat limb ischemia,and it may provide theoretical basis for the critical patients suffered from lower limb ischemic disease.

Congenital Abnormalities ; Encephalocele ; Humans ; Nose Diseases ; congenital

In this paper, the effects of the blend of nanoparticles and microneedle matrix materials on the mechanical properties of dissolving microneedles were studied mainly, so as to construct microneedles with excellent mechanical properties. Different kinds of nanoparticles (calcium carbonate, hydroxyapatite, silica), particle sizes (20, 60, 100 nm) and the proportion of prescription (2%, 6%, 10%) were blended with the matrix material [polyvinyl pyrrolidone (PVP), poly(1-vinylpyrrolidone-co-vinyl acetate)(PVP/VA)] to form dissolving microneedles. The effects of nanoparticles on the elastic modulus and hardness of the microneedles were investigated using a nanoindenter. The results showed that the elastic modulus and hardness of PVP microneedles were significantly improved by nano-calcium carbonate (P < 0.001), and the elastic modulus and hardness of PVP/VA microneedles were significantly improved by nano-hydroxyapatite (P < 0.001). When the particle size of hydroxyapatite was 20 nm, the elastic modulus of PVP/VA microneedles was (10.6 ± 1.0) GPa, and the hardness was (0.47 ± 0.06) GPa. As the size of the nanoparticles increases, the mechanical performance of the microneedles decreases. When the mass proportion of nano-hydroxyapatite increased from 2% to 6%, the elastic modulus and hardness of the microneedles were significantly improved (P < 0.001), but the effect of continue increasing the proportion of nanoparticles on the microneedles was not significant. The nano-enhanced PVP/VA dissolving microneedles has no irritant effect on intact skin and has a slight irritation to damaged skin, but they disappear completely after 72 h. Animal experiments have been approved by the Laboratory Animal Welfare and Ethics Committee of Zhejiang University of Technology. Therefore, the nano-enhanced dissolving microneedles has good biological safety. To sum up, it is necessary to select the appropriate kind of nanoparticle, particle size, and prescription ratio when microneedles constructing with a given matrix material, so as to effectively improve its mechanical performance.

Objective: To evaluate the effect of core∶dentin thickness ratio on the flexure strength, fracture mode and origin of bilayered IPS Empress Ⅱceramic composite specimens. Methods: IPS EmpressⅡ core ceramic, dentin porcelain and bilayered composite specimens with core∶dentin thickness ratio of 2∶1 and 1∶1 were tested in three-point flexure strength. Mean strengths and standard deviations were determined. The optical microscopy was employed for identification of the fracture mode and origin. Results: The flexure strength of dentin porcelain was the smallest (62.7 MPa), and the strength of bilayered composite specimens was smaller than single-layered core ceramic(190.2 MPa). The core∶dentin ratio did not influence the strength of bilayered composite specimens. The frequency of occurrence of bilayered specimen delaminations was higher in the group of core∶dentin thickness ratio of 1∶1 than in the group of 2∶1. Conclusion: IPS Empress Ⅱcore ceramic was significantly stronger than veneering dentin porcelain. Core∶dentin thickness ratio could significantly influence the fracture mode and origin, and bilayered IPS Empress Ⅱceramic composite specimens showed little influence in the fracture strength.

Cardiovascular disease, with high morbidity and mortality, has been threatening the health of human beings. Therefore, expecting to find a more effective therapeutic method, a plenty of researchers devote themselves to the study of the cardiovascular disease all the time. Since discovered on the heart, M3 receptor of muscarinic acetylcholine receptor (mAchR, M receptor) became a new starting point of the research of the cardiovascular disease. With more and more investigation, many people found that M3 receptor could protect the heart from kinds of cardiovascular disease, which may make it a new hopeful therapeutic point. So, expecting to give support to the reference and encouragement for the study of disease related to M3 receptor in future, this review expounds M3 receptor on the heart from the main following aspects: the effect on the heart, the influence on the cardiovascular disease and the mechanism of M3 receptor involved.
Cardiovascular Diseases ; prevention & control ; Heart ; physiology ; physiopathology ; Humans ; Receptor, Muscarinic M3 ; physiology

Humans ; Eosinophilia/diagnosis* ; Thrombosis/etiology* ; Heart Diseases/complications*

Objective To study the treatment of a or toiliac occlusive disease and prevention and management of early complications. Methods From Mar 1998 to Mar 2005, 83 aortoiliac arterial occlusion patients were treated with embolectom y by Forgaty catheter as the main therapy for acute occlusion. In cases of chron ic occlusion percutaneous transluminal angioplasty and stenting, prosthesis graf t bypass surgery as well as proximal endovascular procedure combining with dista l arterial reconstructions were adopted on case to case basis. Results There was acute aortoiliac occlus ion in 14 cases, 6 cases (42.9%) suffered from early complications after embole ctomy, with mortality of 7.1%. In chronic aortoiliac occlusion of 69 cases,va rious complications developed in 16 cases(23.2%),of which aortoiliac arteri al stent placement in 17 cases with complications of 23.5%;prosthesis bypass in 23 cases, with complications of 30.4%, and mortality of 4.3%;aortoili ac stenting combining with femoral-popliteal bypass in 29 cases(58 legs)with complications in 5 cases(17.2%). Conclusion The expansion and development of minimally invasive tech niques along with minimal invasive surgery may reduce surgical risks,decrease m obidity and mortality rate.

Objective To study the cytotoxicity against brain microvessel endothelial cells and blood compatibility in rats of OX26 conjugated endomorphin (EM) loaded hyperbranched polyglycerols-poly(lactic-co-glycolic acid)(HBPG-PLGA) nanoparticles.Methods Prepared nanoparticles were divided into group B (HBPG-PLGA nanoparticles),group EP (EM-HBPG-PLGA nanoparticles) and group OEP (OX26-EM-HBPG-PLGA nanoparticles).The cytotoxicity against brain microvessel endothelial cells (BMECs) of nanoparticles of different groups were measured by MTT test,haemolysis test,normal haemotological parameter and several primary items of coagulation system were tested after nanoparticles of different groups and different dosages injection on rats.Results ①All the three groups of nanoparticles induced decreased cell viability in a dose dependent manner in MTT test,whereas all groups of nanoparticles showed low cytotoxicity against the BMECs during 30 to 600 μg/ml.②There was no significant difference in haemolysis ratio (P＞0.05) and normal haemotological parameter (P＞0.05).③There was no significant difference between the low dosage of all the three groups of nanoparticles and the control group on the function of coagulation system in rats (P＞0.05).④Compared with C group,high dose groups demonstrated longer prothrombin time (PT),activeated partial thromboplasting time (APTT) and lower fibrinogen (Fbg) (P＜0.05).At the same time,compared with the low dose subgroups,PT and APTT were prolonged,Fbg significantly decreased in the high dose subgroups (P＜0.05 or P＜0.01).Conclusion OX26 coupled with EM-HBPG-PLGA nanoparticles showed low cytotoxicity against BMECs and had no significant effect on the coagulation system in rats with low concentration and low dosage.

Objective To explore the change of nerve growth factors(NGF) through the blood brain barrier(BBB) after distal intravenous injection of mannitol into the experimental rats and the effect of exogenous NGF on the expression of growth associated protein-43 in hypoxic-ischemic brain.Methods One hundred cases of 7 days rats were divided into 2 units.One unit was divided into 3 groups:treatment group,control group and sham operated group,20 rats in each group.The other unit was divided into 4 groups:mannitol and NGF treated group,NGF treated group,control group,and sham operated group,there were 10 rats in each group.The model rats with perinatal hypoxic-ischemic brain damage(HIBD) rats were prepared by ligation of left common carotid artery with a temporary systemic hypoxia(inhaling 80 mL/L O2 and 920 mL/L N2).The sections of brains were processed by immunochemistry with antibodies against GAP-43,and the study and memory ability of rats were tested by maze test.The effect of osmotic opening of BBB on the facilitation of NGF′s passage was tested by ELISA.Results The expression of GAP-43 increased after NGF treatment,and the differences were remarkable(P

OBJECTIVETo establish a method for rapid determination of airborne acrylonitrile using a portable gas chromatograph.

METHODSA single standard sample of acrylonitrile was prepared in a laboratory and sampled by the built-in constant flow pump of the portable gas chromatograph. The sample was then preconcentrated by the preconcentrator, thermally desorbed, separated by capillary columns, and detected by a micro argon ionization detector to determine the retention time. Retention time was then used to perform qualitative analysis. Under the set condition of gas chromatography, the external standard method was used to create a standard curve for quantitative analysis of acrylonitrile.

RESULTSThe linear range of acrylonitrile on the portable gas chromatograph was 0.25 to 3.00 mg/m(3). The regression equation was y = 10(-5) x-0.0275, r = 0.9977. The limit of detection was 0.005 mg/m(3), and the lower limit of quantification was 0.25 mg/m(3). The relative standard deviation was lower than 7.09%, and the degree of accuracy was 91.09-105.54%.

CONCLUSIONPortable gas chromatography is a simple, repeatable, and accurate method for rapid determination of airborne acrylonitrile.