Treatment of large segmental defects of long bone has always been a major challenge for the medical community. At present, the bone defects have been treated by autologous or allogeneic bone grafting, free vascularized fibula grafting, Masquelet technique, Ilizarov technique, cylindrical mesh technique and other methods. However, these technical steps are relatively complicated and their cycles are long so that it is difficult to repair the bone defects immediately after surgery and carry out early weight bearing and functional exercise. In recent years, customized 3D printed microporous titanium (tantalum) prostheses have provided a safe and feasible treatment method for repair of these large bone defects. 3D printed microporous titanium (tantalum) prosthesis can accurately reconstruct the anatomical shape of a bone defect, and simultaneously provide stable biomechanical support for the overall bone structure by its mechanical strength of titanium alloy, demonstrating obvious advantages in the repair and regeneration of bone defects. This paper reviewed the characteristics, design requirements, mechanical properties, vascularization challenges and clinical applications of 3D printed microporous titanium (tantalum) prosthesis, and looked ahead to the future development of this new 3D printed prosthesis.

Treatment of large segmental defects of long bone has always been a major challenge for the medical community. At present, the bone defects have been treated by autologous or allogeneic bone grafting, free vascularized fibula grafting, Masquelet technique, Ilizarov technique, cylindrical mesh technique and other methods. However, these technical steps are relatively complicated and their cycles are long so that it is difficult to repair the bone defects immediately after surgery and carry out early weight bearing and functional exercise. In recent years, customized 3D printed microporous titanium (tantalum) prostheses have provided a safe and feasible treatment method for repair of these large bone defects. 3D printed microporous titanium (tantalum) prosthesis can accurately reconstruct the anatomical shape of a bone defect, and simultaneously provide stable biomechanical support for the overall bone structure by its mechanical strength of titanium alloy, demonstrating obvious advantages in the repair and regeneration of bone defects. This paper reviewed the characteristics, design requirements, mechanical properties, vascularization challenges and clinical applications of 3D printed microporous titanium (tantalum) prosthesis, and looked ahead to the future development of this new 3D printed prosthesis.

OBJECTIVE: To analyze the research status and developmental trend of open-access patents at home and abroad of radioactive decontamination technology for human body surface. METHODS: The basic information of open-access patents related to human body radioactive decontamination was searched and collected from the IncoPat Global Patent Database. Based on patent analysis method, the number of patent application, legal status, patent types, application trends, applicants, functional application fields, and citations were analyzed and compared, with focus on their research and development capabilities in domestic and foreign patent application status.RESULTS: A total of 981 patents of radioactive decontamination technology for human body surface were retrieved. Among them, 144 were domestic(14.7%) and 837 were from abroad(85.3%). After merge, 207 patents were confirmed, 88 were from domestic(42.5%) and 119 from abroad(57.5%). The top 5 countries with the most patents were China, Japan, the United States, France and Germany with patent amount of 88, 47, 20, 14 and 13 respectively,accounting for 87.9%(182/207) of all patents. Japan had a large number of patents with a stable growth; France and Germany started patent research very early; the United States focused on technology inheritance; Chinese patent applications are developing rapidly, followed by South Korea, and Russia had few open-access patents. Chinese patent applicants were mainly from Beijing with major enterprises and government organizations. Patents in China had few patent family, foreign patents had a wide distribution, 35.3% of which had more than five of the same family. The proportions of valid patents, utility model patents and patents of integrated device & technology in China were higher than that from abroad(35.2% vs 17.6%, 53.4% vs 3.4%, 62.5% vs 26.9%, P<0.01). The proportion of domestic patents citing other patents in China was lower than that from abroad(13.6% vs 52.1%, P<0.01), but the proportion of Chinese patents cited by other patents showed no statistical significance compared with that of abroad(27.3% vs 39.5%, P>0.05). CONCLUSION: Patents of radioactive decontamination technology for human body surface in China have developed rapidly in recent years. Patent emphasis is placed on integration and multifunctionality. However, the awareness of patent protection and regional layout is not strong enough, and the technical level needs to be improved. It is suggested to propose strategic deployment as soon as possible and strengthen technological research, development and innovation.

Objective To discuss the preliminary experience of transcatheter aortic valve implatantion in patients with severe aortic valve stenosis. Methods The baseline characteristics, hemodynamic changes and clinical outcomes of the patients received TAVI in our institution were analyzed. Results A total of 36 patients underwent TAVI between April 2012 and March 2014. The mean age was (73.4±8.7) years and 24 (66.7%) of them were men. The mean logistic EuroSCORE was (20.6±9.9)%. 25(70%) patients had bicuspid aortic valves. TAVI was successful in 35 patients (97.2%) and valve-in-valve implantation was required in 4 (11.1%) of them. After the procedure, the mean aortic-valve gradient reduced to (10.5±5.7) mmHg. In 2 patients (5.6%), there was marginal moderate periprosthetic leak. At 30 days, the survival rate was 97.2%. Two patients (5.6%) developed who later showed fuel recovery, without significant sequela. Permanent pacemakers were implanted in 10 patients (27.8%) due to the onset of third-degree atrioventricular block after TAVI. To date, the median follow-up duration has exceeded 323 days. 2 patients died of cancer on 374 days and 680 days after TAVI, respectively. Conclusions TAVI is feasible, safe and effective in treating severe stenosis of bicuspid as well as tricuspid aortic valve in selected Chinese patients unsuitable for surgery.

AIM: The aim of this study was to determine the relationship between PAI-1,TIMP-1 gene expression and renal tubulointerstitial fibrosis(TIF) of ureteral obstruction ,and the interfering effects of hepatocyte growth factor (HGF) treatment. METHODS: Sixty rats were divided into normal control, sham operation,unilateral ureteral obstruction(UUO),and rhHGF treated groups (received 0 5 mg?kg -1 ?d -1 HGF for twenty-one days), and were sacrificed at postoperative day 3, 7, 14, 21. The levels of PAI-1, TIMP-1 mRNA were measured by RT-PCR. MMP2 and MMP9 activities were detected by substrate zymography, and renal fibrosis was assessed by measuring tissue hydroxyproline. RESULTS: Compared to controls, expression levels of PAI-1,TIMP-1 mRNA were significantly increased in UUO rats, and this was accompanied by decreased activities of MMP2 and MMP9 and increase in tissue hydroxyproline content. HGF treatment significantly decreased expressions of PAI-1, TIMP-1 mRNA, increased MMP2 and MMP9 activities,and decreased tissue hydroxyproline content in the obstructive kidney. CONCLUSIONS: These results indicate that the increases in PAI-1, TIMP-1 mRNA expression may be the major cause of sustained decreased matrix degradation during the development of tubulointerstitial fibrosis after unilateral ureteral obstruction. rhHGF efficiently ameliorates renal tubulointerstitial injury by the reduction of PAI-1,TIMP-1 mRNA expression, and increasing MMP2, MMP9 activities. [