The in vivo thrombosis evaluation for the biodegradable polymer stent / 生物医学工程学杂志

New biodegradable intravascular stent can reduce risk of foreign bodies retained, thus, it is widely concerned and some of the products have been introduced into the clinic. However, the characteristic of biodegradable may lead to more safety concerns associated with thrombosis. To ensure the safety, the thrombus formation experiment needs to be carefully designed and evaluated based on GB/T 16886.4 standard, but current standard do not provide explicit testing and evaluating methods. Establishing animal model with experimental pigs, the study compares biodegradable coronary stents and metal stents by simulating clinical implantation on the thrombus formation in the implanting process, and after the short-term and long-term implantation. The evaluation methods include gross observation, digital subtraction angiography intraoperative analysis, optical coherence tomography analysis, scanning electron microscopy and so on. The results show that combining these methods could comprehensively evaluate the whole process of the thrombus formation from the beginning of implantation to the end of preclinical animal experiments, so that, it may better predict the clinical thrombosis risk, and the selection of the control was very important. The study tries to use the comparison examples of thrombosis on the new medical instrument to provide the clue for thrombosis evaluation on similar instruments and show the methodology on the preclinical evaluation.

Cloning,expression and bioinformatics analysis of cathepsin B of Echino-coccusgranulosus / 中国血吸虫病防治杂志

Objective To clone and express cathepsin B gene of Echinococcus granulosus(EgCatB)and analyze EgCatB protein by using bioinformatics tools and online databases. Methods The total RNA of E. granulosus was extracted and reverse?ly transcribed into cDNA as the template sequence for PCR. The EgCatB gene was cloned by using the In?Fusion PCR cloning method and expressed by a wheat germ cell?free system,and then the recombinant protein was identified by Western blotting. The signal peptide,transmembrane helices and subcellular location of the EgCatB sequence were predicted by the online soft?ware SignalP 4.1,TMHMM sever v. 2.0 and TargetP 1.1 respectively. Subsequently,the homologue sequence and conserved sites were aligned by using BLASTP and GeneDoc software. Finally,the structures and the glycosylation modification site of the EgCatB encoding protein were analyzed and predicted in turn by ProtParam,SMART,Predictprotein,Swiss?model,NetOGlyc 4.0 and NetNGlyc 1.0 approaches. Results The EgCatB gene was successfully amplified from cDNA of E. granulosus and ex?pressed in the soluble fractions. The molecular weight of the expressed protein was estimated 35 kDa. The bioinformatics analysis revealed that EgCatB was a classical secreted protein containing a Pept_C1 domain. The homology analysis indicated that the amino acid sequence of EgCatB was highly conserved in the active enzyme sites. The protein structure prediction showed a cata?lytic active center was formed through Gln106,Cys112,His282 and Asn302. It was found that there were nine O?glycosylation sites in the EgCatB sequence,but no N?glycosylation sites. Conclusions The EgCatB gene is cloned and expressed successfully,and the recombinant protein is analyzed by bioinformatics approaches and structure predication. The study provides useful informa? tion for further functional study of the EgCatB protein.

Research in operation training mode of new neonatal recovery technology / 中国实用护理杂志

Objective To study the application effect of feedback training mode on new neonatal recovery technology.Methods 101 midwives,obstetric doctors and pediatricians who participated the training were tested about the professional knowledge and skills of new neonatal recovery technology according to the teaching material of neonatal asphyxia recovery and neonatal resuscitation guidelines (2007 revision in Beijing).The results showed no statistical significance.And they were randomly divided into the control group (51 cases) and the observation group(50 cases).The control group adopted traditional method,that was,the teacher taught first and then the students took practice.The observation group used feedback training method.Results The theoretical and technical results of the observation group were significantly higher than those of the control group.The learning motivation,learning initiative,cooperation degree,ability of observation and solving problem and operation proficiency were also significantly higher than those of the control group.Conclusions Feedback training methods can significantly increase the learning effect of perinatal personnel,and make popularized the new neonatal recovery technology.

The comparing study between subchronic toxicity and local implantation response of sodium hyaluronan gels for different application / 生物医学工程学杂志

According to the requirements of ISO10993-11.2006 and ISO10993-6:r2007 standards, we used SD rats for evaluating the subchronic systemic toxicity and local implantation response of two kinds of sodium hyaluronan gels with different application. The results of 90d subchronic toxicity study by intraperitoneal route showed that the animals of the tested group and control group grew normally. There were no differences in the increases of the body weight, haematological index and clinical biochemistry indexes. The examination of gross pathology and histopathology revealed no abnormal changes caused by the test substance during the process. But there was different degree test article residual in the body of the animals at the end of the experiment. It was observed in the local subcutaneous implantation that at the early stage, gel A had mild inflammatory response, cysts were seen clearly, and new blood capillaries were visible at local area. Later, the wall got thinner and dense with little tissue reaction. Gel B also had mild inflammatory response earlier, but it totally disappeared after 14 days of implantation. It can be concluded that the gel products with different characteristics decided its degradation and metabolic process in the body of the test animals and therefore the areas of application of the products clinically. Meanwhile, we compared the evaluation method of subchronic systemic toxicity and local implantation response in risk assessment, providing reference for the choice of biological safe testing.

Biocompatibility analysis of hyaluronic acid sodium gels for medical application / 生物医学工程学杂志

Hyaluronan acid sodium gels are used in ophthalmic surgery, orthopedic treatment and cosmetic surgery. In 2009,there were 12 domestic manufacturers in China producing 33 kinds of products. 23 kinds of imported products were allowed by SFDA to sale in the meantime. Since manufacturers use different production processes, product performances are quite different. According to the GB/T 16886. 1-2001, we designed a pilot program to evaluate the sodium hyaluronate gel products comprehensively in this paper. The results showed that, except chromosome aberration test of gel A and subchronic systemic toxicity of gel C appeared positive, the remaining samples of the test results were negative. This article provides a reference to write standard of cross-linked hyaluronic sodium gel and the revision of standard YY0308-2004.