BACKGROUND:3D printing, a rapid prototyping technology, is considered to be one of the symbols of the third industrial revolution. There are many kinds of 3D printed materials, which have a wide range of clinical applications.OBJECTIVE: To systematically introduce 3D printed biological materials, to summarize the application advances of 3D printing technology in the printing and production of bone, artificial limbs, dentures, skin, blood vessels, stent, implant prosthesis, and tumor models, as well as to investigate the performance conditions of 3D printed biomaterials based on the advantages and disadvantages of the currently used biomaterials, in order to provide reference for future research.METHODS:A computer-based search of CNKI, Wanfang, VIP, CBM, PubMed was performed to search relevant articles published from 2010 to 2016, using the keywords of three-dimensional printing/3D printing/3-D printing; biomaterials; clinical application in Chinese and English, respectively.RESULTS AND CONCLUSION: Great progress in 3D printed biomaterials has been made. However, there are some defects in the existing printed materials, such as high cost, low printing precision and poor biodegradability. Only if the problem of materials is solved, can we continue to develop 3D printing technology. New breakthroughs in 3D printing in the field of medicine have been made, and new technologies and new materials have been applied in clinical practice. Systemic summarization of these application achievements of 3D printing in the field of medicine can provide reference for future medical research.

Objective:To explore the value of shear wave elastography imaging(SWE) in the diagnosis of renal allograft fibrosis and analyze its advantages and limitations.Methods:The renal allograft of 61 patients who underwent renal allograft biopsy from June 2019 to April 2020 in the First Affiliated Hospital of Sun Yat-sen University were included in this study. According to the Banff classification, there were 51 patients with mild-degree fibration(interstitial fibrosis/tubular atrophy, IFTA 0-Ⅰ), and 29 patients with moderate or severe-degree fibration(IFTA Ⅱ-Ⅲ). Two-dimensional ultrasound, color Doppler flow imaging, SWE and kidney function test performed. All the results were compared between the two groups. Diagnostic performance was evaluated by receiver operating characteristic (ROC) curve using pathology as gold standard. The sensitivity, specificity, positive predictive value and negative predictive value were calculated for the diagnosis of moderate or severe-degree fibration.Results:Compared to mild-degree fibration group, creatinine( P<0.001), glomerular filtration rate( P<0.001), RI of arcuate arteries( P=0.022) and SWE value( P<0.001) significantly increased in the moderate or severe-degree fibration group. There were significant correlations between IFTA and creatinine ( r s=0.488, P<0.001), glomerular filtration rate ( r s=-0.452, P<0.001), RI of arcuate arteries( r s=0.228, P=0.042), SWE value( r s=0.584, P<0.001). Taking the cutoff value of SWE value deduced by ROC curve as 21.7 kPa, the area under ROC curve was 0.827. The sensitivity, specificity, positive predictive value and negative predictive value were 86.2%, 74.5%, 61.0% and 89.7%, respectively. Conclusions:There is a good correlation between the SWE value and the degree of fibrosis in the transplanted kidney. SWE can be used to distinguish mild from moderate or severe fibrosis of renal allograft, providing a potential noninvasive method for the assessment of kidney allograft fibration.

Objective:To explore the application value of whole-process ultrasound-guided percutaneous portal vein puncture islet transplantation.Methods:From October 2018 to May 2021, 16 diabetics underwent whole-process ultrasound-guided percutaneous portal vein puncture islet transplantation at First Affiliated Hospital of Sun Yat-sen University.The whole process was guided by ultrasound for completing percutaneous portal vein puncture catheterization, islet infusion monitoring, bleeding prevention and ablation hemostasis after bleeding.Results:Ten patients [8 males and 2 females with a mean age of(45.9±21.1)years]underwent 16 islet transplants, including one islet(5 cases), two islets(4 cases)and three islets(1 case). A single puncture was successfully performed without damage to other extrahepatic organs, persistent portal hypertension, portal vein embolism or infection.Bleeding at liver puncture site occurred in 3 cases and ultrasound radiofrequency ablation was performed for immediate hemostasis.Among them, postoperative blood glucose stabilized at 4~12 mmol/l post-operation.And 5 cases(31.3%)achieved insulin independence for>2 months and 10 cases(62.5%)lowered insulin dosage by>50% as compared with preoperative level.The level of fasting C-peptide recovered or was higher than normal in 10 cases(62.5%)and became obviously elevated in the remainders.In 11 cases(68.8%)of them, liver transaminase was briefly and mildly elevated post-operation, and no other complications were observed.Conclusions:The whole-process ultrasound-guided percutaneous portal vein islet transplantation is both safe and feseasible.It avoids the injury of transplanted kidney caused by contrast agent and radiological radiation to operator and patient.It is a method of islet transplantation worth a wider popularization.

OBJECTIVE：To investigate the effects of gypenosides （GPs）on gene expression of major urinary proteins （Mups） in liver tissue of hypercholesterolemia model mice. METHODS ：C57BL/6J mice were divided into control （ND）group，model （HFD）group and GPs therapy （GP）group according to body weight （BW），with 11 mice in each group. Except for ND group ， other groups were given high-lipid diet to induce hypercholesterolemia model. From the 17th week of feeding ，ND group and HFD group were given constant volume of 0.1％CMC-Na solution intragastrically ；GP group were given GPs suspension （250 mg/kg） intragastrically，once a day ，for consecutive 22 weeks. BW ，the levels of blood glucose （BG）and blood lipid （TC，LDL-C）were detected in each group. Total RNA of liver tissue was extracted ，and reverse transcription library was constructed and RNA-seq sequencing was performed. The differentially expressed genes were screened by PCA ，volcano map and scatter plot. RT-qPCR was used for verification for differentially expressed genes. The correlation between the expression of differentially expressed genes and the above pharmacodynamic indexes was analyzed by bivariate analysis. RESULTS ：Compared with ND group ，BW，the levels of BG，TC and LDL-C in HFD group were increased significantly （P＜0.05）. Compared with HFD group ，above indexes of GP group were decreased significantly except for BW （P＜0.05）. PCA showed that the data of ND group and HFD group distributed in different quadrants ，and the data distribution of GP group was between above two groups. mRNA of Mup4，Mup5，Mup11，Mup15 and Mup21 in liver tissue of mice were increased significantly after treated with high-fat diet （P＜0.05）. mRNA of Mup3，Mup4， Mup5，Mup8，Mup12 and Mup21 were decreased significantly after treated with GPs （P＜0.05）. In ND group vs. HFD group and HFD group vs. GP group ，mRNA of Mup4，Mup5 and Mup21 genes changed significantly and the trend was opposite. Results of RT-qPCR verification showed that compared with ND group ，relative mRNA expression of Mup4，Mup5 and Mup21 gene were increased significantly in HFD group （P＜0.05）. Correlation analysis revealed that mRNA expression of Mup5 was positively correlated with the levels of TC and BG （r＝0.727 1，0.670 6，P＜0.05），mRNA expression of Mup4 and Mup21 were positively correlated with the level of BG （r＝0.737 8，0.721 5，P＜0.05）. CONCLUSIONS ：GPs can regulate the expression of Mups genes in liver tissue of hypercholesterolemia model mice ， and reduce glucose and lipid level through regulating the mRNA over-expression of Mup4，Mup5 and Mup21.