Vascular Remodeling Process of Heparin-Conjugated Poly(ε-Caprolactone) Scaffold in a Rat Abdominal Aorta Replacement Model.

In the field of vascular graft research, poly-ε-caprolactone (PCL) is used owing to its good mechanical strength and biocompatibility. In this study, PCL scaffold was prepared by electrospinning and surface modification with heparin via hexamethylenediamine. Then the scaffolds were implanted into the infrarenal abdominal aorta of Wistar rats and contrast-enhanced micro-ultrasound was used to monitor the patency of grafts after implantation. These grafts were extracted from the rats at 1, 3, and 6 months for histological analysis, immunofluorescence staining, and scanning electron microscopy observation. Although some grafts experienced aneurysmal change, results showed that all implanted grafts were patent during the course of 6 months and these grafts demonstrated well-organized neotissue with endothelium formation, smooth muscle regeneration, and extracellular matrix formation. Such findings confirm feasibility to create heparin-conjugated scaffolds of next-generation vascular grafts.

Feasibility of poly (ϵ-caprolactone-co-DL-lactide) as a biodegradable material for in situ forming implants: evaluation of drug release and in vivo degradation.

The purpose of this study was to evaluate the technical feasibility of poly (ϵ-caprolactone-co-DL-lactide), P (CL/DL-LA), for injectable in situ forming implants (ISFI). The ISFI was prepared by dissolving P (CL/DL-LA) in N-methyl-2-pyrrolidone (NMP), and Testosterone undecanoate (TU) was used as model drug. The effect of various polymer concentrations, molecular weights (Mws) and drug loads on the drug release from the TU-loaded ISFI systems was investigated in vitro. The release of TU-loaded ISFI was also evaluated in rats. In addition, a subcutaneous rabbit model was used to evaluate the degradation and foreign-body reaction of P (CL/DL-LA) ISFI. The use of higher concentration of P (CL/DL-LA) with higher molecule weight and larger CL:DL-LA monomer ratio for the TU-loaded ISFI gave a slower drug release. The ISFI of 80/20 P (CL/DL-LA) (Mw 61 753):NMP 20:80 with 16% TU formulation increased serum testosterone levels in rats over a period of three months. The in vivo degradation and biocompatibility study of ISFI shows that P (CL/DL-LA) degrades by a process of bulk degradation and that the foreign-body reaction of this biomaterial is relatively mild. In summary, our investigations demonstrate that in situ parenteral drug delivery systems can be obtained from P (CL/DL-LA) solutions.

High-efficient nano-carrier gel systems for testosterone propionate skin delivery.

The purpose of the current investigation was to evaluate the skin delivery potential of the different nano-carrier gels including liposomal gel, ethosomal gel and microemulsion gel bearing testosterone propionate (TP) as a testosterone deficient therapy. The prepared nano-particles were characterized for their shape, particle size distribution and zeta potential. In vitro skin permeation and in vivo transdermal delivery of nano-carrier gels were studied with the Franz diffusion cells and confocal laser scanning microscopy (CLSM). The results showed that all of nano-particles were almost spherical with low polydispersity and nano-metric size range from 40 to 200 nm. TP ethosomal gel also provided an enhanced transdermal flux of 7.64 ± 1.4 µg/cm(2)/h and a decreased lag time of 0.69 h across rat skin as compared with the other two formulations. The skin penetration efficiency of TP nano-carrier gels also revealed that TP ethosomal gel would enhanced penetration of rhodamine red (RR)-loaded formulation to the deeper layers of the skin (268 µm) than the liposomal gel (192 µm) and microemulsion gel (228 µm). This study demonstrated TP ethosomal gel is a promising nano-carrier for delivering TP through the skin.

Endovascular stenting vs. extrathoracic surgical bypass for symptomatic subclavian steal syndrome.

PURPOSE: To analyze the immediate and long-term outcomes of endovascular stenting vs. extrathoracic surgical bypass for subclavian steal syndrome. METHODS: From 1989 to 2010, 252 consecutive patients (173 men; mean age 62 years) with vertebrobasilar and upper extremity symptoms of subclavian steal were treated with balloon-expandable stents (n=148) or extrathoracic surgical bypasses (n=104: 71 axilloaxillary and 33 carotid-subclavian) using polytetrafluoroethylene grafts. RESULTS: The technical success rate was 97.3% in the stent group vs. 99.0% for the bypass group (p=0.605). There was no perioperative mortality or any permanent neurological deficit in either group. The overall perioperative complication rate was 6.1% in the stent group vs. 9.6% in the bypass group (p=0.295). The 10-year target vessel revascularization rate was 46.6% for stenting vs. 5.8% for bypass (p<0.001). The cumulative primary patency rates at 1, 3, 5, and 10 years were 91%, 78%, 67%, and 49% for the stent group vs. 99%, 97%, 95%, and 89% for the bypass group (p<0.001). The cumulative secondary patency rates were 95%, 91%, 86%, and 64%, respectively, for the stent group vs. 99%, 99%, 98%, and 94% for the bypass group (p=0.001). No difference was detected in overall survival curves between the groups (p=0.527). CONCLUSION: Both endovascular stenting and extrathoracic surgical bypass are safe and effective treatments for subclavian steal syndrome in the short and medium term; however, extrathoracic surgical bypasses are more durable in the long term.

Development of novel hydrophilic and antibacterial silicone rubber impression material for dental application.

OBJECTIVES: This investigation aimed to develop a novel hydrophilic and antibacterial silicone rubber impression material for dental application. METHODS: The basic formula of the new silicone rubber was determined on a preliminary study, and 6% polyether modified silicone oil was added as wetting agent to provide the hydrophilicity. No-vel nano-antibacterial inorganic fillers containing quaternary ammonium salt with long chain alkyl were incorporated into the hydrophilic silicone rubber impression materials at a mass fraction of 0%, 1%, 2%, 3%, 4%, or 5%. A commercial silicone rubber impression material was used as control. The mechanical properties, wettability, detail reproducibility, dimensional stability, and mixing time of silicone rubber materials were measured. Thin-film adhesion method and cell counting kit-8 method were used to detect the antibacterial property and cytotoxicity. Scanning electron microscopy (SEM) was chosen to observe the micromorphology of the novel silicone rubber. RESULTS: When the content of antibacterial filler exceeded 4%, the mechanical properties of the new silicone rubber decreased significantly (P<0.05). Compared with those of the control group, the contact angle and linear size change rate of different groups had no significant change at different time nodes, and the detail reproducibility was intact (P>0.05). The addition of antibacterial fillers had no significant effect on the mixing time (P>0.05). Adding 4% antibacterial fillers could result in the antibacterial rate of 95.26%, showing good antibacterial properties. No significant difference was found in the cytotoxicity of all groups (P>0.05). The SEM pictures of the cross section of the silicone rubber sample showed that the fillers had good compatibility with the silicone rubber matrix and distributed in the matrix evenly. CONCLUSIONS: A novel silicone rubber impression material containing 6% polyether modified silicone oil could obtain promising hydrophilic and antibacterial properties after being added with 4% antibacterial inorganic fillers.

NOD2 is involved in regulating odontogenic differentiation of DPSCs suppressed by MDP through NF-κB/p65 signaling.

Dental pulp stem cells (DPSCs) are well known for their capable of both self-renewal and multilineage differentiation. Dental tissue diseases, include caries, are often accompanied by inflammatory microenvironment, and muramyl dipeptide (MDP) is involved in the inflammatory stimuli to influence the differentiation of DPSCs. Nucleotide-binding oligomerization domain 2 (NOD2), a member of the cytosolic Nod-like receptor (NLR) family, plays a key role in inflammatory homeostasis regulation, but the role of NOD2 in DPSCs differentiation under inflammatory is still unclear. In this study, we identified that MDP suppressed odontogenic differentiation of DPSCs via NOD2/ NF-κB/p65 signaling pathway. Alizarin red staining and ALP activity showed the odontogenic differentiation was suppressed by MDP in a concentration-dependent manner, and the expression of dentin differentiation marker protein dentin matrix protein 1 (DMP-1) and dentin Sialophosphoprotein (DSPP) also indicated the same results. The expression of NOD2 increased gradually with the concentration of MDP as well as the phosphorylation and nuclear translocation of p65, which meant NF-κB signaling pathway was activated. Further, the interference of NOD2 inhibited the phosphorylation and nuclear translocation of p65 and reversed the MDP-mediated decrease of odontoblast differentiation of DPSCs. Our study showed that MDP can inhibit the odontoblast differentiation of DPSCs in a concentration-dependent manner. The NF-κB signaling pathway was activated by increasing expression of NOD2. Interference of NOD2 reversed the negative ability odontoblast differentiation of DPSCs in the inflammatory environment. Our study might provide a theoretical basis for the clinical treatment for dentinogenesis of DPSCs.

Classical risk factors of cardiovascular disease among Chinese male steel workers: a prospective cohort study for 20 years.

BACKGROUND: Cardiovascular disease (CVD) constitutes a major public health problem in China and worldwide. We aimed to examine classical risk factors and their magnitudes for CVD in a Chinese cohort with over 20 years follow-up. METHODS: A cohort of 5092 male steelworkers recruited from 1974 to 1980 in Beijing of China was followed up for an average of 20.84 years. Cox proportional-hazards regression model were used to evaluate the risk of developing a first CVD event in the study participants who were free of CVD at the baseline. RESULTS: The multivariable-adjusted hazard ratio (HR) associated with every 20 mmHg rise in systolic blood pressure (SBP) was 1.63 in this Chinese male population, which was higher than in Caucasians. Compared to non-smokers, men who smoked not less than one-pack-a-day had a HR of 2.43 (95% confidence interval [CI], 1.75-3.38). The HR (95% CI) for every 20 mg/dl increase in total serum cholesterol (TC) and for every point rise in body mass index (BMI) was 1.13 (1.04-1.23) and 1.06 (1.02-1.09), respectively. CONCLUSIONS: Our study documents that hypertension, smoking, overweight and hypercholesterolemia are major conventional risk factors of CVD in Chinese male adults. Continued strengthening programs for prevention and intervention on these risk factors are needed to reduce the incidence of CVD in China.

Ultra-low graphene oxide loading for water permeability, antifouling and antibacterial improvement of polyethersulfone/sulfonated polysulfone ultrafiltration membranes.

The aqueous dispersion of graphene oxide (GO) was employed as additive to fabricate antifouling and antibacterial polyethersulfone (PES)/sulfonated polysulfone (SPSf)/GO mixed matrix membranes (MMMs) by the non-solvent induced phase separation (NIPS). The effect of different amounts of GO on the morphology and performance of MMMs were studied. The results showed that the casting solution exhibited an increasing trend in viscosity with increment in GO concentration (from 0 to 0.016 wt%) owing to the hydrogen bonding (H-bonding) interaction among GO, H2O and SPSf. Raman and molecular dynamic (MD) simulations analyses confirmed that there existed H-bonding interaction among SPSf, GO and H2O. Specifically, the agglomeration of GO was inhibited and stable homogeneous casting solution was obtained. Meanwhile, the H-bonding interaction also played a key role in the MMMs structure and improved properties. It was found that GO nanosheets were uniformly embedded to form many cellular-like voids in the asymmetric PES/SPSf/GO MMMs with a sponge-like structure. The pure water flux of the MMMs with a very low GO content of 0.012 wt% was up to 816.9 L/m2h and the rejection of bovine serum albumin (BSA) was more than 99.2% under a pressure of 0.1 MPa. Additionally, the mechanical properties of MMMs was also improved with the increase of GO content. Importantly, the MMMs displayed excellent antifouling and antibacterial performance. A high fouling recovery (94.2%) and antibacterial rate (90.0%) against Escherichia coli (E. coli) obtained were attributed to improved hydrophilicity, enhanced negative charge and GO nano-size effect. In summary, our study provides a simple approach to tailor MMMs with the enhancement of permeation, antifouling and antibacterial properties at a very low content of GO.

Polysulfone-graft-4'- aminobenzo-15-crown-5-ether based tandem membrane chromatography for efficient adsorptive separation of lithium isotopes.

Adsorptive membrane-based chromatography can provide the high separation efficiency common to column chromatography but at a lower working pressure. Herein, a novel membrane chromatography system for lithium isotope adsorptive separation is reported. It uses polysulfone-graft-4'-aminobenzo-15-crown-5-ether (PSf-g-AB15C5) porous membranes (0.52 mmol/g of immobilization crown ether, average pore size of 62.7 nm, porosity of 80.4%) as a stationary phase packed in a chromatography column (Ø 25 × 100 mm). Furthermore, a four-stage tandem membrane chromatography system was designed to enhance lithium isotope separation performance. The partial eluate from the former column was used as the feed solution for the next stage. Results show that the flow rate of the eluent could reach 18 mL/h owing to the lower internal diffusion resistance of membranes. Meanwhile, adsorption isotherms and adsorption kinetics show that Li+ adsorption was an exothermic and spontaneous process. The surface diffusion, multilayer adsorption and ion-pore electrostatic interaction between Li+ and the crown ether groups on the membranes played a key role in the separation of 7Li+ and 6Li+ by membrane chromatography. The separation factor obtained from the single-stage membrane chromatography was up to 1.0232. The abundances of 7Li+ and 6Li+ gradually increased with an increase in the elution stages. The relative abundances of 7Li+ and 6Li+ obtained from the four-stage tandem membrane chromatography increased by 0.26% (from 92.40 to 92.66%) and 0.2% (from 7.60 to 7.80%), respectively. In conclusion, our current research opens a new avenue for the simultaneous enrichment of 7Li+ and 6Li+ during lithium isotope adsorptive separation.

Tuning J-type dimers of non-peripherally substituted zinc tetra-4-tert-butylphenophthalocyanine.

It was found, by UV-vis and TOF-MS, that the head-to-tail dimers of non-peripherally substituted zinc tetra-4-tert-butylphenophthalocyanine are inclined to form in non-coordinated solvent, e.g. chloroform and especially in dilute solution under 1.25 x 10(-6)mol/mL. The aforementioned dimers in solution can be tuned by altering concentration or adding coordinated solvent, e.g. methanol, which might be further improved to a practical strategy for preparation of J-aggregates in the future.

Antibacterial and environmentally friendly chitosan/polyvinyl alcohol blend membranes for air filtration.

An antibacterial and environmentally friendly chitosan (CS) /polyvinyl alcohol (PVA) blend membrane for air filtration was prepared via nonsolvent induced phase separation (NIPS) method. The chemical structure, thermal behavior, morphology, mechanical property and surface charge of the resultant CS/PVA membranes were characterized. Results showed that CS and PVA were miscible due to the intermolecular hydrogen bond between them. The blend membrane obtained from over 20 wt.% CS concentration exhibited a gradient interconnected porous structure without skin layer. The air filtration efficiency and pressure drop obtained from CS/PVA membrane with 30 wt.% CS concentration and the thickness of 37 µm under a face velocity of 5.3 cm s-1 were 95.59% and 633.5 Pa, respectively. The performance of air filtration obtained is mainly attributed to the direct interception of membrane surface. Further, the antibacterial rate of the blend membrane was up to 94.8% for E. coli and 91.3% for S. aureus.

Surgical treatment of 82 patients with diabetic lower limb ischemia by distal arterial bypass.

BACKGROUND: Diabetic lower limb ischemia is a serious complication of diabetes mellitus. This study was conducted to investigate the effectiveness of distal arterial bypass treatment in diabetic patients with lower limb ischemia. METHODS: From July 2000 to July 2004, 96 lower limbs of 82 diabetic patients (type 2) with severe lower limb ischemia were treated in Xuan Wu Hospital. Arterial bypass with femoro-popliteal polytetrafluoroethylene (PTFE) and graft-tibial autologous grafts was performed on 31 limbs (32.3%). Popliteal-tibial artery bypass alone was performed on 22 limbs (22.9%). Combined iliac artery stenting, femoro-popliteal artery PTFE graft bypass, and graft-tibial artery autologous graft bypass was performed on 12 limbs (12.5%), and femoro-tibial artery graft bypass was performed on 10 limbs (10.4%). Popliteal-tibial-pedal artery graft bypass was performed on 7 limbs (7.3%). RESULTS: Arterial grafts in 92 limbs of 79 patients were patent on discharge. Three patients with 4 ischemic limbs (3.7%) died of respiratory failure 12 hours, 3 days and 7 days after operation respectively. Early operation success rate was 96.3% (79/82). Graft patency rate of patients on discharge was 95.8% (92/96). The short-term total effectiveness rate was 83.3% (80/96). Foot ulcer healing rate was 35.7% (10/28). 97.4% (75/77) patients were followed up for a mean of 13.5 months. The long-term total effective rate was 80.7% (71/88). The total amputation rate was 4.5% (4/88). Mortality was 4.5%. The total graft patency rate was 90.9% (80/88). CONCLUSION: In the treatment of diabetic foot, distal lower limb arterial bypass can help to avoid amputation or lower the amputation level, and may promote foot ulcer healing and improve patient's quality of life.

[Surface modification of vascular tissue engineering biomaterial by low temperature plasma with NH3, CO2 and O2].

OBJECTIVE: To study the biocompatibility of poly (hydroxybutyrate-hydroxyvalerate) (PHBV) modified by low temperature plasma with NH3, CO2, and O2 with canine Endothelial cells (ECs) and provide the better materials for blood vessel tissue engineering via surface modification. METHODS: PHBV was modified by low temperature plasma with NH3, CO2, and O2, for 0, 5, 10, 20, and 30 min respectively, PHBV not modified was used as control group. The contact angle was measured. X-ray photoelectron spectroscopy was used to detect the surface elements. Canine endothelial cells (ECs) were cultured on the surface of PHBV and were stained with fluorescence isothiocyanate (FITC). Their morphological characteristics were observed with fluorescence microscopy, and the cell proliferation was detected with MTT assay. RESULTS: The surface contents of carbon of the PHBV modified by low temperature plasma with O2 and CO2 were 63.75% and 69.72%, both lower than that before modification (77.97%). The surface contents of oxygen of the PHBV modified by low temperature plasma with O2 and CO2 were 30.72% and 28.48%, both higher than that before modification (21.74%). The surface content of nitrogen of the PHBV modified by low temperature plasma with NH3 was 3.25%, remarkably higher than that before modification (0). The contact angles of different modification groups, especially those of the 5 min groups, were all significantly smaller than that of the unmodified group (P < 0.05 or P < 0.01). Compared with the control group, the cytocompatibility was better in the low temperature plasma modified groups. CONCLUSION: The surface of PHBV modified by low temperature plasma with NH3, CO2, and O2 has active groups and good biocompatibility, so the surface modification of low temperature plasma with NH3, CO2, and O2 can be a kind of effective method for the tissue engineering blood vessel.

Tensile and shear methods for measuring strength of bilayer tablets.

Both shear and tensile measurement methods have been used to quantify interfacial bonding strength of bilayer tablets. The shear method is more convenient to perform, but reproducible strength data requires careful control of the placement of tablet and contact point for shear force application. Moreover, data obtained from the shear method depend on the orientation of the bilayer tablet. Although more time-consuming to perform, the tensile method yields data that are straightforward to interpret. Thus, the tensile method is preferred in fundamental bilayer tableting research to minimize ambiguity in data interpretation. Using both shear and tensile methods, we measured the mechanical strength of bilayer tablets made of several different layer combinations of lactose and microcrystalline cellulose. We observed a good correlation between strength obtained by the tensile method and carefully conducted shear method. This suggests that the shear method may be used for routine quality test of bilayer tablets during manufacturing because of its speed and convenience, provided a protocol for careful control of the placement of the tablet interface, tablet orientation, and blade is implemented.

Triton X-100 combines with chymotrypsin: A more promising protocol to prepare decellularized porcine carotid arteries.

BACKGROUND: Morbidity and mortality of cardiovascular diseases are increasing in recent years. To solve these problems, vascular transplantation has become a common approach. Decellularization has been a hot spot of tissue engineering to prepare vessel substitutes for vascular transplantation. However, there is no established canonical protocol for decellularization thus far. OBJECTIVE: To further understand the decellularization effect of decellularization protocols and the causal relationship between decellularization and mechanical properties. METHODS: Three decellularization protocols including two chemical protocols based on SDS and Trypsin respectively and a combination of Triton X-100 with chymotrypsin were adopted to obtain decellularized porcine carotid arteries in our study. After decellularization, histological analysis, scanning electron microscopy and mechanical tests were performed to evaluate their efficiency on removing of cellular components, retention of extracellular matrix and influence on mechanical properties. RESULTS: All these decellularization protocols used in our study were efficient to remove cellular components. However, SDS and trypsin performed more disruptive effect on ECM structure and mechanical properties of native arteries while Triton X-100 combines with chymotrypsin had no significant disruptive effect. CONCLUSIONS: Compared with decellularization protocols based on SDS and trypsin, Triton X-100 combines with chymotrypsin used in our study may be a more promising protocol to prepare decellularized porcine carotid arteries for vascular tissue engineering applications.

New and practical mathematical model of membrane fouling in an aerobic submerged membrane bioreactor.

This study aimed to develop a practical semi-empirical mathematical model of membrane fouling that accounts for cake formation on the membrane and its pore blocking as the major processes of membrane fouling. In the developed model, the concentration of mixed liquor suspended solid is used as a lumped parameter to describe the formation of cake layer including the biofilm. The new model considers the combined effect of aeration and backwash on the foulants' detachment from the membrane. New exponential coefficients are also included in the model to describe the exponential increase of transmembrane pressure that typically occurs after the initial stage of an MBR operation. The model was validated using experimental data obtained from a lab-scale aerobic sponge-submerged membrane bioreactor (MBR), and the simulation of the model agreed well with the experimental findings.

Engineering the Surface of Smart Nanocarriers Using a pH-/Thermal-/GSH-Responsive Polymer Zipper for Precise Tumor Targeting Therapy In Vivo.

Nanocarrier surface chemistry plays a vital role in mediating cell internalization and enhancing delivery efficiency during in vivo chemotherapy. Inspired by the ability of proteins to alter their conformation to mediate functions, a pH-/thermal-/glutathione-responsive polymer zipper consisting of cell-penetrating poly(disulfide)s and thermosensitive polymers bearing guanidinium/phosphate (Gu+ /pY- ) motifs to spatiotemporally tune the surface composition of nanocarriers for precise tumor targeting and efficient drug delivery is developed. Surface engineering allows the nanocarriers to remain undetected during blood circulation and favors passive accumulation at tumor sites, where the acidic microenvironment and photothermal heating break the pY- /Gu+ binding and rupture the zipper, thereby exposing the penetrating shell and causing enhanced cellular uptake via counterion-/thiol-/receptor-mediated endocytosis. The in vivo study demonstrates that by manipulating the surface states on command, the nanocarriers show longer blood circulation time, minimized uptake and drug leakage in normal organs, and enhanced accumulation and efficient drug release at tumor sites, greatly inhibiting tumor growth with only slight damage to normal tissues. If integrated with a photothermal dye approved by the U.S. Food and Drug Administration (FDA), polymer zipper would provide a versatile protocol for engineering nanomedicines with high selectivity and efficiency for clinical cancer treatment.

Biofouling and control approaches in membrane bioreactors.

Membrane fouling (especially biofouling) as a critical issue during membrane reactor (MBR) operation has attracted much attention in recent years. Although previous review papers have presented different aspects of MBR's fouling when treating various wastewaters, the information related to biofouling in MBRs has only simply or partially reviewed. This work attempts to give a more comprehensive and elaborate explanation of biofilm formation, biofouling factors and control approaches by addressing current achievements. This also suggests to a better way in controlling biofouling by developing new integrated MBR systems, novel flocculants and biomass carriers.

Effects of hydraulic retention time and bioflocculant addition on membrane fouling in a sponge-submerged membrane bioreactor.

The characteristics of activated sludge and membrane fouling were evaluated in a sponge-submerged membrane bioreactor (SSMBR) at different hydraulic retention times (HRTs) (6.67, 5.33 and 4.00h). At shorter HRT, more obvious membrane fouling was caused by exacerbated cake layer formation and aggravated pore blocking. Activated sludge possessed more extracellular polymeric substances (EPS) due to excessive growth of biomass and lower protein to polysaccharide ratio in soluble microbial products (SMP). The cake layer resistance was aggravated by increased sludge viscosity together with the accumulated EPS and biopolymer clusters (BPC) on membrane surface. However, SMP showed marginal effect on membrane fouling when SSMBRs were operated at all HRTs. The SSMBR with Gemfloc® addition at the optimum HRT of 6.67h demonstrated superior sludge characteristics such as larger floc size, less SMP in mixed liquor with higher protein/polysaccharide ratio, less SMP and BPC in cake layer, thereby further preventing membrane fouling.

[Primary experimental study on the construction of tissue engineering blood vessel].

OBJECTIVE: To explore the primary experimental methods to construct tissue engineering blood vessel. METHODS: Using the collagen-chitosan to prefabricate the scaffolds with 3-dimensional structure, the proliferated human endothelial cells (ECs), smooth muscle cells (SMCs) and fibroblasts act as the seed cells. The cells were seeded to scaffolds in two-step method, and engineering tissue were matured by static culture or bioreactor culture. Extracellular matrix contents and the platelet aggregation were examined in engineering tissue, tissue engineering blood vessels were taken as patches to repair the man-made defaults on the rats aorta. RESULTS: The proliferated human ECs, SMCs and fibroblast can hold activity and act as seed cells. The prefabricated scaffolds, with excellently cell and tissue biocompatibility, can facilitated cells adherence and upgrowth, the cells quantities and extracellular matrix contents in engineered tissue are time dependent increase (P < 0.05). Platelet aggregation tests confirm the tissue engineering blood vessel have some anti-coagulability. Using the engineering tissue patch to repair the default, 6 aortas in 8 animal were patency till 10 days post-operation. CONCLUSIONS: The seeding cells can be seeded on the 3-dimensional collagen-chitosan scaffolds and matured, the tissue engineering blood vessel can be constructed primarily.