Objective To evaluate the feasibility to fabricate tissue engineered heart valve leaflet with poly hydroxybutyrate co hydroxyvalerate (PHBV) scaffold. Methods Constructive characteristics of PHBV were observed by scanning electron microscope. PHBV was implanted subcutaneously in rabbit and extirpated at 2,4,6,8, and 10 weeks in order to study its biocompatibility and biodegradability. Cell growth curve, smooth muscle α actin and ultra microscopic characteristics were observed in canine aortic valve interstitial cells. The cells were seeded on the PHBV and their function of prostaglandin I 2 (PGI 2) synthesis was determined. Results Porous diameter of PHBV was 130μm, PHBV had good biocompatibility and completely degraded at the end of the 10th week. Smooth muscle α actin were expressed in canine aortic valve interstitial cells and grew well. Cells implanted on PHBV grew well, PGI 2 were synthesized and secreted( P lt;0.05). Conclusion It is feasible to fabricate a tissue engineering heart valve leaflet in vitro with PHBV scaffold.
ObjectiveTo analyze the clinical outcome of anterior cervical discectomy and fusion using a Zero-profile interbody fusion and fixation device (Zero-P) for cervical spondylotic myelopathy. MethodsBetween April 2011 and September 2013, 26 cases of cervical spondylotic myelopathy underwent anterior cervical discectomy and fusion with the Zero-P. Of 26 cases, 12 were male and 14 were female, aged 43-82 years (mean, 58.3 years). The disease duration was from 3 months to 10 years (mean, 5.9 years). The involved segments included C3,4 in 5 cases, C4,5 in 3 cases, C5,6 in 6 cases, and C6,7 in 12 cases. The clinical outcome was evaluated using visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, and Neck Disability Index (NDI) score before operation and after operation. ResultsThe operations were successful and the operation time was 75-140 minutes (mean, 105 minutes); and blood loss was 20-150 mL (mean, 45 mL). There was no complications of infection, neural injury, esophageal fistula, prevertebral hematoma, or leakage of cerebrospinal. Dysphagia occurred in 1 case within 1 week after operation,and disappeared after 1 month. All patients were followed up for an average of 15.3 months (range, 12-18 months). The clinical symptoms were relieved after operation. During follow-up, no implant displacement or subsidence, screw breakage, and cervical instability were observed. At 3 and 12 months after operation, the VAS score and NDI reduced significantly (P<0.05); the JOA score increased significantly (P<0.05); and the intervertebral space height and the cervical Cobb angle improved significantly (P<0.05). But there was no significantly difference between at 3 and 12 months (P>0.05). According to JOA evaluation, the results were excellent in 14 cases, good in 10 cases, and fair in 2 cases, with an excellent and good rate of 92.3% at last follow-up. ConclusionThe clinical outcome of anterior cervical discectomy and fusion using a Zero-P is satisfactory and reliable in the treatment of cervical spondylotic myelopathy. It can restore the cervical physiological curve and the intervertebral space height and decrease the incidence of postoperative dysphagia.
As one of the stimulus-response polymeric intelligent materials, shape memory polymers have been widely applied in biomedicine due to their better biocompatibility, higher controllability, stronger deformation restorability and biodegradability compared with shape memory alloys and shape memory ceramics. This review will introduce the structural principles of shape memory polymers and summarize their applications in the treatment of vascular diseases, especially in endovascular therapy. At the same time, the related technical problems and the future of shape memory polymers are prospected. With the continuous development of processing technology and materials, it can be predicted that shape memory polymers will be more widely used in the medical field.
Implantation of drug-eluting stents (DES) is one of the most effective treatment for intraluminal vascular diseases such as vascular stenosis caused by atherosclerosis. Antiproliferative drugs offered by could significantly reduce the restenosis of blood vessels, which is beneficial to interventional therapy in more advanced and complex vascular diseases. This review sumarizes the state-of-the-art of the DES based on the function of loaded drug and material of the stents. We hope this review can provide basic information of DES for clinicians and researchers to make more rational choices in practical applications. Moreover, this review also propses the prospects of drug-loaded stents.