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

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.

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.

Objective　To explore a new way of treating refractory residual gallstones by endoscopy. Methods　Choledochfiberscope(CHF) combined with air pressure ballistic lithoclast(APBL) under ureterscopy were used on 28 cases of large or impacted residual gallstones. Results　All refractory stones were crushed and extracted completely in 1-3 times, including sufficient once in 16, twice in 10 and thrice in 2. No severe complications were occurred in this series. Conclusions　This procedure is a safe, effective, simplicity, less complication and no heat injury methods. It is proved to be a new way of treating refractory residual gallstones, especially for large or impacted lithiasis. It is worthy for clinical application widely in the future.

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 observe the effects of Astragalus injection, astragaloside IV and formononetin on proliferation and Akt phosphorylation of basal-like human breast carcinoma cell lines MDA-MB-468 and MDA-MB-231. Methods: The effects of different concentrations of Astragalus injection, astragaloside IV and formononetin on proliferation of breast cancer cell lines were assayed by methyl thiazolyl tetrazolium (MTT) assay, and their effects on phospho-Akt were assayed by in-cell Western blot method. Results: The results of the MTT assay showed that the best concentrations of Astragalus injection, astragaloside IV, formononetin and astragaloside IV plus formononetin were 1 g/mL, 80 mug/mL, 40 mug/mL and 10 mug/mL plus 40 mug/mL respectively. After 1- or 2-day culture, Astragalus injection, astragaloside IV, formononetin and astragaloside IV plus formononetin decreased the expressions of p-Akt (Thr 308) and p-Akt (Ser 473) in MDA-MB-468 cells. Formononetin and astragaloside IV plus formononetin down-regulated the expression of p-Akt (Thr 308) protein in MDA-MB-231 cells after 1- and 2-day culture, but had no effects on the expression of p-Akt (Ser 473) protein in MDA-MB-231 cells. Conclusion: Astragalus injection, astragaloside IV and formononetin can inhibit proliferation of breast cancer cell lines MDA-MB-468 and MDA-MB-231, and the antiproliferation effects vary according to their concentrations. And the antiproliferation mechanisms may be related to their down-regulation effects on Akt phosphorylation.

Objective To establish a nude mouse model of low rectal cancer with lymph node metastasis, to detect the expression of E-calcium (E-cad) in the serum and transplanted tumor tissue of the mice, and to analyze the role of E-cad in lymph node metastasis of rectal cancer.Methods Human colorectal adenocarcinoma cells (SW-480) were inoculated into the rectal submucosa of nude mice to establish a model of low rectal cancer with lymph node metastasis.120 nude mice were randomly divided into three groups (40 mice in each group).Group A (rectal cancer model group) was injected with dimethylhydrazine and implanted with SW480 cells.Group B (dimethylhydrazine control group) was injected with dimethylhydrazine alone.The group C (control group) received no treatment.Serum E-cad was detected by ELISA.The mRNA and protein expression of E-cad in the tumor tissue was detected by RT-PCR and western blot, respectively.Results The serum level of E-cad in group A was 19.48±1.25 mg/L, significantly higher than those in groups B (2.36±0.18 mg/L) and C (2.15±0.12 mg/L) (t =8.28, 9.01, P < 0.05).The serum levels of E-cad were significantly higher in the nude mice with lateral lymph node metastasis than those without lymph node metastasis (t =10.28, P < 0.05).The protein expression of E-cad in the group A was lower than that in the groups B and C (t =9.81, 7.69, P < 0.05).In the group A, the protein expression of E-cad in the nude mice with lateral lymph node metastasis was significantly lower than that without lateral lymph node metastasis (t =9.36, P < 0.05).The mRNA expression of E-cad in the group A was significantly lower than that in the groups B and C (P < 0.05), and the mRNA expression of E-cad in the nude mice with lateral lymph node metastasis was significantly lower than that in the mice without lateral lymph node metastasis (t =7.85, P < 0.05).Conclusions The serum level of E-cad may be closely associated with the lymphatic metastasis of rectal cancer, and the mRNA and protein expressions of E-cad in colorectal cancer tissue were weak or absent, leading to a decrease of adhesion ability between cancer cells, and promote the invasion and metastasis of cancer cells.

Objective To explore a new way of treating refractory residual gallstones by endoscopy. Methods Choledochfiberscope(CHF) combined with air pressure ballistic lithoclast(APBL) under ureterscopy were used on 28 cases of large or impacted residual gallstones. Results All refractory stones were crushed and extracted completely in 1 3 times, including sufficient once in 16, twice in 10 and thrice in 2. No severe complications were occurred in this series. Conclusions This procedure is a safe, effective, simplicity, less complication and no heat injury methods. It is proved to be a new way of treating refractory residual gallstones, especially for large or impacted lithiasis. It is worthy for clinical application widely in the future.

Objective To investigate the effect of ectopic pregnancy tubal resection or common disease retention on female reproductive endocrine and menstrual traits.Methods 286 patients with ectopic pregnancy lapa-roscopic operation were selected.According to the different treatment methods,the patients were divided into resection group (n =199),retention group 87 cases,in surgical operation on the third day and the thirtieth day and tested for female reproductive hormone (P,LH,FSH,E2 )and human chorionic gonadotropin (hCG).Results Resection group in the third day after surgery of FSH[(8.5 ±4.9)IU /mL]was significantly higher than that of preserving group[(3.9 ± 0.9)IU /mL],with significant difference (t =5.44,P <0.05),the amounts of LH,E2 ,P and HCG were insignificant (t =0.56,1.24,0.82,all P >0.05).30 days after the surgery,there was no significant difference between the two groups in FSH,LH,E2 ,P and HCG (t =0.92,0.77,1.02,0.65,all P >0.05),but at the age of more than 40 years old and bilateral absence of fallopian tube in patients with,menorrhagia and menstrual cycle change obviously,and female ovarian endocrine function to reduce the clinical symptoms.Conclusion Tube resection has some influence on the ovarian function of tubal ectopic pregnancy,especially older,lack of bilateral fallopian tube.

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