1.Status of 3D Printing Technology for Preparing Bioceramic Materials.
Jun ZHANG ; Mingli LI ; Bincai TANG ; Han DONG ; Qiong YU
Chinese Journal of Medical Instrumentation 2023;47(6):651-658
3D printing technology has great advantages in small batch and personalized customization, so it has attracted much attention in the biomedical field. The consumables available for 3D printing include polymer, metal, ceramic and derived materials. Biomedical ceramics, with high melting point and poor toughness, are the most difficult materials to be used in 3D printing. The progress of 3D printing ceramic preparation process using ceramic powder, ceramic slurry, ceramic wire, ceramic film and other different raw materials as consumables are reviewed, and the surface roughness, size, density and other parameters of ceramics prepared by SLS, 3DP, DIW, IJP, SL, DLP, FDM, LOM and other different processes are compared. The study also summarizes the clinical application status of 3D printed bioceramics in the field of hard tissue repair such as bone tissue engineering scaffolds and dental prostheses. The SL ceramic additive manufacturing technology based on the principle of UV polymerization has better manufacturing precision, forming quality and the ability to prepare large-size parts, and can also endow bioceramics with better biological properties, mechanical properties, antibacterial, tumor treatment and other functions by doping trace nutrients and surface functional modification. Compared with the traditional subtractive manufacturing process, the bioceramics prepared by 3D printing not only have good mechanical properties, but also often have better biocompatibility and osteoconductivity.
Bone and Bones
;
Ceramics
;
Printing, Three-Dimensional
;
Tissue Engineering
;
Tissue Scaffolds
2.Practice of integrated theory and experiment teaching of systematic anatomy for international students
Shihai KAN ; Zhiqiang WANG ; Dongmei ZHAO ; Fei LIU ; Zhenhai YU ; Changzhu JIN
Chinese Journal of Medical Education Research 2020;19(4):420-423
Anatomy is an important medical course for international medical students. In order to improve the teaching quality and enhance the extent of students' learning, teachers integrated the theoretical and experimental courses of systemic anatomy, and introduced the "Digital Human" anatomical system to compensate the shortage of models, so as to realize the integrated theory and experiment teaching of systematic anatomy. Practice indicated that integrated teaching mode of theory and experiment was more consistent with the learning habits of foreign students, which improved their learning effect with significant advantages. But there were still some problems in this teaching mode and measures for solving these problems were proposed in this paper.
4.Controlled Release of Low Molecular Protein Insulin-like Growth Factor-1 through Self-Assembling Peptide Hydrogel with Biotin Sandwich Approach.
Yanfei LIU ; Zhenhai FAN ; Yuying WANG ; Limei YU
Journal of Biomedical Engineering 2015;32(2):387-392
Since the release rate of protein in hydrogels is directly dependent upon the size of the protein and the hydrogel, how to deliver low molecular weight protein for prolonged periods has always been a problem. In this article, we present a usage of self-assembling peptide (P3) with the RGD epitope on its N terminus. The concentration of the released insulin-like growth factor 1 (IGF-1) was determined by UV-vis spectroscopy and the release kinetics suggested a notable reduction of the IGF-1 release rate. Cell entrapment experiments revealed that IGF-1 delivery by biotinylated nanofibers could promote the proliferation of the mouse chondrogenic ATDC5 cells when compared with cells embedded within nanofibers with untethered IGF-1.
Animals
;
Biotin
;
Cell Line
;
Delayed-Action Preparations
;
Drug Carriers
;
chemistry
;
Hydrogels
;
chemistry
;
Insulin-Like Growth Factor I
;
pharmacology
;
Mice
;
Nanofibers
;
Oligopeptides
;
chemistry
5.Role and mechanism of retinoic acid in axonal regeneration
Shixing WU ; Zhenhai YU ; Fang LIU ; Haiyan LIN ; Zhiying ZHANG ; Chuansen ZHANG
Chinese Journal of Tissue Engineering Research 2014;(15):2450-2454
BACKGROUND:Retinoic acid signaling pathways is very important in the formation pf nervous system, specialization of neurons and outgrowth of axons. The recent studies show that, retinoic acid plays an important role in the process of axonal regeneration, but few research reports its exact molecular mechanism.
OBJECTIVE:To analyze and summarize the mechanism underlying retinoic acid signaling pathways in the process of axonal regeneration.
METHODS:A computer-based online research was conducted among the VIP, CNKI, PubMed, BioMed Centeral, Springer, The Free Medical Journals, EBSCO and Foreign Journals Integration System between January 2000 and December 2013, with the key words of“retinoic acid, the central nervous system, nerve damage, axon regeneration, and mechanism”in Chinese and English. A total of 43 studies addressing the molecular mechanism of retinoic acid in axonal regeneration were screened. According to the supplementary documents, another five references were added. Repetitive research and atypical reports were excluded.
RESULTS AND CONCLUSION:Fol owing acute central nervous system injury, axonal regeneration and functional recovery are extremely limited. For proper functionality fol owing injury, axons must regrow, reinnervate their targets, and remyelinate their axons. When the central nervous system injuries occur, retinoic acid signaling pathways express transcription factor retinoic acid receptorβ2 to induce axonal regeneration fol owing injury;in dorsal root ganglion neurons, cAMP levels are greatly increased by lentiviral retinoic acid receptorβ2 expression and contribute to neurite outgrowth. More recently, retinoic acid-retinoic acid receptorβ2 pathways directly transcriptional y repress a member of the inhibitory Nogo receptor complex, Lingo-1, under an axonal growth inhibitory environment in vitro as wel as fol owing spinal cord injury in vivo. Through these molecular mechanisms, retinoic acid signaling pathways play its important role in the process of axonal regeneration.
6.Human amnion-derived mesenchymal stem cells transplantation improves hematopoietic function of myelosuppression mice
Guanping YAO ; Limei YU ; Zhenhai FAN ; Ning FANG ; Fei REN ; Jiao LUO ; Xiaoyu ZHANG ; Yuying WANG ; Jinwei LIU
Chinese Journal of Tissue Engineering Research 2013;(23):4248-4255
10.3969/j.issn.2095-4344.2013.23.010
7.Single-center experience of steroid-free immunosuppressive therapy after liver transplantation for hepatocellular carcinoma patients
Tonghai XING ; Zhenhai YU ; Zhihai PENG
Chinese Journal of Organ Transplantation 2013;34(11):671-675
Objective To evaluate the efficacy and safety of using basiliximab in place of a corticosteroid for immunosuppression following liver transplantation for hepatocellular carcinoma (HCC) in Chinese patients.Method The records of 178 patients with HCC who underwent orthotopic liver transplantation from January 2003 to December 2009 were retrospectively reviewed.All patients received immunosuppression therapy that contained either basiliximab (n =78) or steroids (n =100) in addition to tacrolimus and mycophenolate mofetil.Assessments included complications related to liver transplantation,occurrence of steroid side effects,recurrence of HCC,and patient and graft survival.Results A smaller proportion of patients receiving basiliximab than steroids experienced de novo diabetes (38.7% vs.91.0%,respectively) or long-term de novo diabetes mellitus (4.0% vs.30.3%,respectively) (both,P<0.0001).The median overall and disease free survival was similar between basiliximab (50.8 months and 19.6 months,respectively) and steroid treated patients (64.2 months and 23.8 months,respectively).The 5-year overall survival and disease free survival rate was also similar between the basiliximab (42.5% and 38.9%,respectively) and steroid (50.5% and 39.2%) groups (all,P>0.730).However,in patients who met the Milan criteria basiliximab was associated with greater 5 year overall survival rate than steroid therapy (88.9% vs.57.4%,respectively,P =0.022).Conclusion It revealed that the non-steroid treatment does not increase the incidence of acute rejection but also can decrease the incidence of de novo diabetes in the patients with HCC following liver transplantation and prolong the survival time of patients who met the Milan criteria.
8.Modified Walker's procedure for the treatment of postoperative rebleeding in portal hypertensive patients
Minghai WANG ; Shuguang ZHANG ; Zhenhai YU ; Guangxin LI ; Kun WANG ; Shiyong QIN ; Changle RUAN
Chinese Journal of General Surgery 2013;28(9):690-692
Objectives To evaluate modified transthoracic esophageal transection (modified Walker's procedure) for management of postoperative rebleeding of portal hypertension.Methods Since 1983,we adopted modified Walker's operation to make low esophageal transection and transect intraabdominal recurrent varix of the coronary vein in the treatment of esophageal variceal rebleeding in portal hypertensive patients who had received previous surgeries aiming at portal hypertension.Results In 53 cases of postoperative rebleeding of portal hypertension,49 cases underwent elective operation with no mortality,4 cases received emergency surgery,one died post-operatively due to hepatic failure.The postoperative control rate of recurrent bleeding was 100%,and the overall postoperative mortality was 2%.The longest postoperative survival time was 24 years,and the 5-year survival rate was 77%.There were no postoperative recurrent hemorrhage and hepatic encephalopathy.Conclusions Modified transthoracic esophageal transection (modified Walker's procedure) is easy to perform,good at saving operative time,with a reliable immediate hemostatic effect and long-term control of variceal hemorrhage,hence is a effective remedy operative method for postoperative rebleeding of portal hypertensive patients after failed previous operations.
9.Construction of multiple drug release system based on components of traditional Chinese medicine.
Dan LIU ; Xiaobin JIA ; Danhong YU ; Zhenhai ZHANG ; E SUN
China Journal of Chinese Materia Medica 2012;37(15):2338-2343
With the development of the modernization drive of traditional Chinese medicine (TCM) preparations, new-type TCM dosage forms research have become a hot spot in the field. Because of complexity of TCM components as well as uncertainty of material base, there is still not a scientific system for modern TCM dosage forms so far. Modern TCM preparations inevitably take the nature of the multi-component and the general function characteristics of multi-link and multi-target into account. The author suggests building a multiple drug release system for TCM using diverse preparation techniques and drug release methods at levels on the basis the nature and function characteristics of TCM components. This essay expounds elaborates the ideas to build the multiple traditional Chinese medicine release system, theoretical basis, preparation techniques and assessment system, current problems and solutions, in order to build a multiple TCM release system with a view of enhancing the bioavailability of TCM components and provide a new form for TCM preparations.
Animals
;
Biological Availability
;
Chemistry, Pharmaceutical
;
methods
;
Dosage Forms
;
Drug Delivery Systems
;
methods
;
Drugs, Chinese Herbal
;
chemistry
;
pharmacokinetics
;
Humans
;
Medicine, Chinese Traditional
10.Study on hepatocyte-like cells differentiated from human peripheral blood mononuclear cells labeled by the Fluorescent Dye PKH26 in vivo
Youlin YU ; Baomin SHI ; Xiuyan WANG ; Zhongxue SU ; Xiaofei LU ; Zhenhai ZHANG ; Xiaogang SUN ; Feng LIANG
Chinese Journal of Hepatobiliary Surgery 2012;18(7):548-551
ObjectiveTo induce human peripheral blood mononuclear cells differentiate into hepatocyte-like cells by hepatocyte growth factor (HGF) and fibroblast growth factor-4 (FGF-4) in vitro and determine whether PKH26 could be used to serve as an effective tracer for the cells,and observe the ability of transplanted hepatocyte-like cells differentiate into hepatic cells in nude mice.MethodsGroup A and B were set up respectively.In Group A,mononuclear cells were cultivated without hepatocyte growth factor (HGF) and fibroblast growth factor-4 (FGF-4) in cell culture.They were used as negative control group.In Group B,mononuclear cells were cultured with the administration of both HGF and FGF-4 to induce the differentiation into liver hepatocyte-like cells.The changes in cell morphology were observed and the expressions of AFP and CK 19 were detected by immunocytochemical staining in two groups at different times after induction.The hepatocyte-like cells differentiated from human peripheral blood mononuclear cells labeled by the fluorescent dye PKH26 injected into caudal vein in nude mice is experimental group.The nude mice injected with equal amount of normal saline in control group.The migration of the labeled cells into the liver are observed by the fluorescence microscope in the hepatic tissue sections of nude mice and the expressions of ALB were detected by immunocytochemical staining two weeks after the cells transplantation.ResultsCells in group B have a strong proliferative activity.It becomes large and oval,grows in colonies following induction.Cells in group A that showed spherical shape when peripheral blood mononuclear cells were just isolated are gradually becoming inconformity in morphology,spindle or fibroid,and a few cells are round:cells developed apoptosis and cracked following incubation.The expressions of AFP and CK19 were positive after induction in group B as detected by immunocytochemicat staining.Inversely,the expressions of AFP and CK19 were negative in group A after incubation.The experimental group showed numerous PKH26 labeled cells in the hepatic tissue sections of nude mice.But the control group did not show PKH26 labeled cells.The expressions of ALB were positive in the experimental group as detected by immunocytochemical staining after two weeks of the cells transplantation.ConclusionHuman peripheral blood mononuclear cells have the potential to differentiate into hepatocyte-like cells under the induction of HGF and FGF-4.Additionally,PKH26 is an effective tracer in hepatocyte-like cell transplantation.The hepatocyte-like cells settled in hepatic tissue begin to differentiate into mature hepatocyte after two weeks of the cells transplantation.It plays hepatic cells function and expresses alhnmin.

Result Analysis
Print
Save
E-mail