The differentiation of stem cells into target cells in a particular region is an important prerequisite for the organ construction and tissue engineering. The processes are multi-directionally regulated by the surface properties of biomaterials, and among them the influences of mechanical rigidity and surface morphology of biomaterials on morphological characteristics, focal adhesion assemblies, and cytoskeletal structure of cells are considered to be the most important factors in regulating the differentiation of stem cells into specific cell lineages. This review summarizes the progresses on this topic in the past few years, which may provide a reference to the design of the biomaterials in regenerative medicine and tissue engineering.
Biocompatible Materials ; metabolism ; Cell Differentiation ; Cell Lineage ; Humans ; Musculoskeletal System ; cytology ; metabolism ; Regenerative Medicine ; Stem Cells ; cytology ; Surface Properties ; Tissue Engineering

OBJECTIVE:To study the effect of selenium chitosan on differentiation of HL60 cells and its relationship with the c-myc and c-fos protein expression of cells. METHODS:HL60 cells were divided into 5 groups,i.e. 25 mg?L-1 selenium chitosan group,50 mg?L-1 selenium chitosan group,100 mg?L-1 selenium chitosan group,blank control group and positive control group (dimethy sulfoxide). The differentiation of HL60 cells was measured by NBT-reduced method after administration and amount of positive cells was detected. FCM was used to examine the c-myc and c-fos protein expression of cells. RESULTS:As compared with blank control group,differentiation effect of selenium chitosan groups were similar to that of positive control group; NBT-reduced positive cells were increased while c-myc protein expression of cells was decreased(P

OBJECTIVE To explore the relationship between the change in Toll-like receptor expression and prognosis of severe viral hapatitsis.METHODS The peripheral blood mononuclear cells were separated and the expression of TLR2 and TLR4 mRNA was observed by reverse transcription-polymerase chain reaction(RT-PCR).The level of serum endotoxin was measured by chromogenic substrate Limulus amebocyte lysate assay.The data were analyzed by SPSS 11.5 software.RESULTS The expression of TLR2 and TLR4 mRNA and the level of serum endotoxin of death group before therapy were lightly higher than that of survival group,but after therapy that of death group is higher than survival group(P

Objective To explore the methods of improving the immune function of dendritic cells(DCs) from patients with chronic type B hepatitis in vitro. Methods Monocytes from type B hepatitis patients and healthy controls were incubated with GMCSF and IL-4 and IFN-? to induce dendritic cells(DCs) generation.Then the nutrien-concentration sodium selenite was added for co-culture before the maturity of DCs.The samples were separated into three groups: hepatitis-B patients (group A),hepatitis-B patients with Se(group B),healthy control(group C).The phenotypes of DCs including CD80,CD86 were characterized by flow cytometry(FCM) and the response of allogeneic lymphocytes was detected by MTT assay.The concentration of cytokines in the supernatant such as IL-12 was tested by ELISA assay. Results After the nutrien-concentration Se was added for co-culture,the proliferation ability of isotype xenoma lymphocyte stimulated by DCs was obviously streng thened compared with group A,and the excretion level of IL-12 also increased(P

With the development of medicine and health,the experts who have a good command of medicine and law are in great social need,so the major of medical law was introduced.This article,based on the experience and construction of medical law major in Kunming Medical College,put forward that the major of medical law must establish the cultivation goals curriculum system and projects of internship.It emphasizes the approaches to improving the students' knowledge of Arts and comprehensive abilities.

Objective To identify and clone rat aging-related genes to provide clues for human aging mechanism. Methods Improved different display reverse transcript-PCR method was applied to identify differentially expressed genes in cortex tissues of 4-month and 24-month old BALB/c mouse. Results Forty-two cDNA fragments with differential expression were identified, and 21 with increase and 21 with decrease of expression in old mice. Among them, 17 represented genes with known protein function, 12 represented known gene sequences but their protein function was unknown, and the other 13 probably belonged to new cDNAs. Among the genes with known protein function, 2 genes were associated with oxidative stress, 3 with energy production, and 4 with protein metabolism, respectively. Additionally, gene expression alterations were also found in those related to cell apoptosis, neurodegenerative disorder, and growth and development regulation. Conclusions Rat aging might be related with the alteration of oxidative stress status, energy production and protein metabolism.

OBJECTIVE:To promote the drug use in a legal way.METHODS:The legal issues were analyzed,which included standardization of specially administrated drugs,exchange or replacement of prescribed drugs,usage and dosage of prescribed drugs,informed consent of patients,etc.RESULTS&CONCLUSION:There still exist problems in clinical drug use,the relevant laws and regulations should be further standardized and identified.

BACKGROUND:Great saphenous vein is the most common vascular material in coronary artery bypass grafting, however, the graft neointimal hyperplasia and subsequent atherosclerosis result in angiostegnosis, which affect the long-term efficacy. OBJECTIVE: To analyze the pathophysiology and mechanism of the angiostenosis, additionally, to construct smooth muscle cell specific SM22a promoter and SMHC enhancer. METHODS: The database of PubMed, HighWire and CNKI were retrieved with key words of "SM22α promoter, SMHC enhancer, stenosis, Pi3k and RNAi/RNA interference". The language was confined to English and Chinese. The literatures correlated with angiostenosis, VSMC-specific SM22α promoter and enhancer were selected. The reviews and overlapped researches were excluded. In vascular smooth muscle cell proliferation and apoptosis of graft neointimal hyperplasia, as well as the extent of graft thrombosis were considered as evaluation index. RESULTS AND CONCLUSION: More than 8 730 literatures were searched by the computer. According to inclusion and exclusion criteria, the SM22α promoter and angiostenosis were analyzed. The neointimal hyperplasia and thrombosis had a strong impact on prospective efficacy after coronary artery bypass grafting. The PI3K-Akt-mTOR pathway was a crucial signal passage which regulated cell proliferation and migration. RNA interference targeting Pik3cb can efficiently suppress the neointimal hyperplasia through down regulating the PI3K-Akt-mTOR pathway. The shRNA eukaryon expression plasmid vectors targeting rat Pik3cb were constructed using VSMC-specific SM22α promoter. On the one hand, it can suppress the neointimal hyperplasia, and on the other, it can prevent the occurrence of thrombosis.SM22a is a specific gene in vascular smooth muscle cell. The studies that applied VSMC-specific SM22α promoter/enhancer to vascular grafting provide a new strategy to prevent angiostenosis and thrombosis.

ObjectiveTo summarize and investigate the occurrence,clinical features and treatment of cesarean scar pregnancy.Methods33 cases of cesarean scar pregnancy were retrospectively analyzed.Results10 cases of vaginal massive hemorrhage after uterine curettage,9 cases of subtotal hysterectomy,1 case was cured by MTX treatment,13 cases were cured by conservative treatment of uterine curettage after chemotherapy treatment,10 cases of successful uterus-saving by excision of lesion and uterine repair.ConclusionTransvaginal sonography was an important method in diagnosis of cesarean scar pregnancy and,the key to success was to select the appropriate individual treatment according to classification by transvaginal sonography.

Objective To investigate the results of hearing screening in newborns and infants so as to explore the appropriate clinical strategy of hearing screening among newborns and infants. Methods Transiently evoked otoacoustic emission(TEOAE) was used to examine the hearing of newborns and infants. Those who fail the initial screening underwent secondary screening with TEOAE. Acoustic brain-stem response(ABR) was used to monitor the hearing of those who failed the secondary screening. Results A total of 6 150 infants were taken hearing screening but only 5 597(91%) passed the first screen,A total of 103 newborns were hearing screening but only 93(90. 29%)for the first screen. Conclusion Hearing screening in the procedure with TEOAE helps identify infants with hearing loss as early as possible so as to conduct appropriate intervention and pormote development of speech and language.