BACKGROUND: It has been verified vascular endothelial cells can propagate and differentiate into vessel by planted in the tissue-engineered material in vivo, but it may cause severe trauma when obtain vascular endothelial cells, and it has limited sources. OBJECTIVE: To investigate whether bone marrow mesenchymal stem cells (BMSCs) can differentiate into vascular endothelial cells by combined induction of vascular endothelial cell growth factor (VEGF), basic fibroblast growth factor (bFGF) and insulin-like growth factor (IGF)-1 by experimental observation. DESIGN, TIME AND SETTING: The control cell observation experiment was conducted at the Central Laboratory of First Affiliated Hospital, Liaoning Medical University from November 2006 to June 2007. MATERIALS: An 8-week-old Japanese big ear rabbit was used to isolate BMSCs. VEGF, bFGF and IGF-1 were purchased from Peprotech Company. METHODS: After anaesthesia, bone marrow was extracted from the rabbit. Enough BMSCs were harvested by adherence and trypsinization and randomized into two groups. BMSCs in the induction group were inoculated in DMEM supplemented with 10% fetal bovine serum (FBS), 10 ?g/L VEGF, 1 ?g/L bFGF and 2 ?g/L IGF-1 for 2 weeks. BMSCs in the control group were inoculated in DMEM containing 10% FBS. MAIN OUTCOME MEASURES: Morphological observation, nitric oxide (NO) content detected, immunohistochemistry staining of Ⅷ factor-related antigen and Weibel-Palade body under a electron microscope in BMSCs. RESULTS: Five days after induction, BMSCs were distributed in cluster, showing round. Non-induced BMSCs were evenly distributed, showing spindle or triangle. Fourteen days after induction, NO content in supernatant was significantly higher in the induction group than in the control group (t=3.75, P

Bone defect repair is a complicated process of connective tissue repair under the control of various cytokines.It is the ample blood supply which is a necessary condition to promote regeneration of fracture,especially bone defect and nonunion.Hypoxia inducible factor 1 can induce formation of neovascularization with perfect physiological function in the lesion of bone defect by regulating various gene expression,and thus provide nutritional support and favorable conditions to metabolism for different cells in the process of osteogenic differentiation and osteogenic activity to promote the healing of fracture.Both gene therapy and using hypoxia inducible factor 1 directly have an ability to promote neovascularization in the lesion of fracture.It is a hotspot at present that hypoxia inducible factor 1 in the field of bone tissue engineering is used to treat bone defect.Hypoxia inducible factor 1 transgenic therapy needs further research in the repairing process of bone defect.

With the emergence of tissue engineering techniques, using tissue engineering methods and tools to repair cartilage defects become a new treatment model, while looking for a suitable carrier of chondrocytes is the current focus of the study in cartilage tissue engineering. In this paper, synthetic biodegradable polymers and natural extracellular matrix substitutes (natural polymers) make progress in two areas reviewed.

BACKGROUND: Anterior cruciate ligament (ACL) is the kernel of articular genu, for the past few years, the incidence rate of cruciate ligament injury increased gradually.OBJECTIVE: To review on the mechanism of the injury of ACL, the method of operation, the election of transplant, the reconstruction of equilong, the reconstruction of ligament and so on, and to look forward to providing some references on treating the ACL injury.METHODS: A computer-based research was conducted in Medine database (1996-01/2009-03), with the key words of "Anterior cruciate ligament, implant, reconstruction, repair". Chongqing VIP database and Qinghua Tongfang database (1996-01/2009-03) were retrieved with the same key words.RESULTS AND CONCLUSIONS: 200 literatures on arthroscopic ACL reconstruction were collected, excluding older, repeated and similar research, and the 18 standard literatures were included. ACL is a key structure to stabilize knee joint, and exercises and various factors during daily life could induce its injury. Unsuitable treatment would severely affect movement ability or movement loss. To recover structure and function of knee joint, damaged ACL should be reconstructed. With the development of technique and innovation of surgical instrument, arthroscopic reconstruction has presently been a popular method to treat ACL. There are many methods to treat ACL injury, but none of them can duplicate ACL anatomical relationship. It is still in doubt whether the operation can reduce the secondary damage. We have much more work to research on modus operandi, implant, postoperative rehabilitation and other adjunctive therapies.

The vaseularization of tissue-engineered bone is the key problem which the development and employment of large sized tissue-engineered bone.The vascular endothelial cell has a great effect on promoting vascularization in tissue-engineered bone.Vascularizations fall into two modes of vaseulogenesis and angiogenesis according to differences in source of endothelial cells.Co-culture of osteoblasts and vascular endothelial cells has better result than single culture of each kind of cells.Different ways of improving the vascularization,such as searching for new source of vascular endothelial cell,co-culture and in vivo experiment are investigated to meet the challenge of bone tissue engineering.

BACKGROUND: Whether bone morphogenetic protein 2 (BMP-2) can be transduced into marrow stromal cells (MSCs) and produce osteogenic effects by viral or non-viral vector remains unclear? OBJECTIVE: To observe the expression of cultured rabbit MSCs transfected with pcDNA3-hBMP2 in vitro. Simultaneously, the MSCs were transfected but not screened and then transplanted into autologous muscle to investigate the osteogenic capability by X-ray. DESIGN, TIME AND SETTING: A controlled observation experiment was performed at the Department of Orthopedics, Liaoning Medical University between November 2004 and April 2005. MATERIALS: Six adult New Zealand rabbits, of either gender, weighing 2.0-3.0 kg, were included for this study. BMP2 antibody was the product of Sanaka Company, USA. pcDNA3-hBMP2 was provided by Professor Pu Qin from the Department of Biochemistry, Fourth Military Medical University of Chinese PLA). Restriction enzyme was purchased from Takara biotechnology (Dalian) CO., LTD., China. METHODS: Super-purified plasmid pcDNA3-hBMP2 was extracted from E. coli. Bone marrow was taken from the adult rabbit femur for harvesting MSCs by density gradient separation. The MSCs were divided into the following 4 groups: Group A, cells were transfected and screened by G418; Group B, cells were transfected by pcDNA3-hBMP2; Group C, cells were transfected by empty vector pcDNA3; Group D, only transfection reagent Fugene 6 was added.MAIN OUTCOME MEASURES: Transient BMP2 expression was analyzed by immunohistochemistry. Expression of osteocalcin and collagen I was examined by immunohistochemistry and in situ hybridization, respectively. Two weeks after transfection, MSCs from the group B were autologously transplanted into the muscle. Four weeks later, X-ray assay was used to observe bone formation.RESULTS: pcDNA3-hBMP2 was successfully transduced into MSCs and transiently expressed BMP2 100%. Four weeks after gene transfection, expression levels of osteocalcin and collagen I were significantly higher in the group A than in the groups C and D. X-ray results demonstrated new bone formation four weeks after MSCs transplanted into the muscle.CONCLUSION: pcDNA3-hBMP2 can safely and efficiently transfect MSCs and induce them to differentiate towards osteoblasts by secreting BMP2.

Objective To explore a new method for lacrimal passage irrigation after laser dacryocystoplasty surgery. Method One-hundred patients (104 eyes), which underwent laser dacryocystoplasty surgery combined with lacrimal drainage tube indwelling, were divided into two groups. In Group A (50 patients, 52 eyes), lacrimal passage irrigation was performed by traditional No.5 needle. While in Group B (50 patients, 52 eyes), it was done by No.7 blunt round needle designed by the researchers. Lacrimal passage irrigation was performed three times, each at the 3rd day, 1 week and 1 month after surgery. The silicone tube was removed 3 months after surgery and the treatment was evaluated. Results The total effective rate was 64% (32/50) in Group A and 92%(46/50) in Group B. The difference was statistically significant (χ2=18.537, P < 0.01). Conclusions The No.7 blunt round needle showed better effect when used for lacrimal passage irrigation after laser dacryocystoplasty surgery. It could improve the efficiency of lacrimal passage irrigation, thus decreasing irrigation times and reducing psychological pressure for the patients, which is worthy of clinical application.

A novel hemizygous frameshift mutation in exon1of DAX-1 gene (993delC) was found in a patient with late-onset adrenal hypoplasia congenita and hypogonadotropic hypogonadism.This mutation led the stop codon to appear in advance of 59 amino acids.His mother and two sisters were the carriers of this hemizygous mutation while his father and brother were wild-type.After glucocorticoid hormone replacement therapy, the clinical symptom was improved, but the level of ACTH was not suppressed.

Objective:To explore the effects of exosomes derived from bone-marrow endothelial progenitor cells(EPCs-Exos)on the angiogenesis and collagen deposition in vitro,and to illustrate the possible mechanism for EPCs-Exos to accelerate the cutaneous deficiency repair.Methods:The endothelial progenitor cells (EPCs) were isolated, cultivated and identified;at the same time, the EPCs-Exos were also isolated and identified.The EPCs-Exos uptake in EPCs was observed and analyzed.16 rats were randomly divided into 4 groups, and then the models of skin defect were established, respectively.The equal volume of PBS and 50, 100, 150 mg·L-1 EPCs-Exos were injected into the area around skin defect of the rats in 4 groups.The wound closed sizes on the 0, 3rd, 7th and 14th days were measured, and Masson''s trichrome staining and CD31 immunofluorescence staining were performed on the 14th day for evaluating the tissue healing efficacy after EPCs-Exos treatment.In vitro,the mediums containing PBS and 50, 100, 150 mg·L-1 EPCs-Exos were used to culture the human umbilical vein endothelial cells (HUVECs), respectively.Scratch test and tubule formation assay were used to detect the migration and capillary network formation of HUVECs.At the same time, Western blotting was used for analyzing the expression level of angiogenesis related gene vascular endothelial growth factor A (VEGFA) in HUVECs.Results: The primary EPCs were isolated and identified successfully, and EPCs-Exos were purified and characterized.The CD31 immunofluorescence staining and double staining of DiL-ac-LDL and FITC-UEA-I of EPCs were positive.The electron microscope results showed that EPCs-Exos were nearly spheroidal, with the diameter about 40-100 nm.For the models of rat skin injury treated by EPCs-Exos, with the increasing of injection doses, the sizes of skin defect scar were gradually reduced, the degrees of scar healings were gradually increased,and the differences between various groups were statistically significant (P< 0.05).EPCs-Exos promoted the collagen maturity of healing skin in a dose-dependent manner;on the 14th day, the effect in 150 mg·L-1 EPCs-Exos group was the most significant.In vitro, EPCs-Exos promoted the migration and capillary network formation of HUVECs and increased the expression level of VEGFA;the migration rate,the net number of branches and the expression level of VEGFA in 150 mg·L-1 EPCs-Exos group were significantly higher than those in 50 mg·L-1 EPCs-Exos group and PBS group (P< 0.05).Conclusion: EPCs-Exos can promote the repair of traumatic skin defect of the rats by positively regulating the vascular endothelial cell function.

Objective To observe the effect of angiotensin-converting enzyme inhibitors (ACEI) on anemia and erythropoietin (EPO) requirements in maintenance hemodialysis patients. Methods Ninety maintenance hemodialysis patients with hypertension and anemia were divided into 2 groups by random digits table, observation group (45 cases, using ACEI as antihypertensive treatment), control group [45 cases,using calcium channel blocker (CCB) as antihypertensive treatment]. The follow-up period after starting ACEI or CCB therapy was one year. The hemoglobin concentration, serum EPO, EPO requirements were compared after 0, 2, 4, 6, 8, 10, 12 months' treatment. Results In response to ACEI, the mean hemoglobin value in observation group decreased progressively, reaching statistical significance after 6 months, and it had significant difference compared with that in control group [6 months: (94.21±9.20) g/Lvs. (105.55±9.16) g/L,12 months: (95.90±6.75) g/L vs. (105.81±4.45) g/L,P <0.05]. The EPO requirements experienced a progressive increase in observation group and reached statistical significance after 8 months, compared with those in control group [8 months: ( 10 090.75±1918.35) U/week vs. (7010.32±1600.15) U/week, 12 months: (11 586.39±2009.76) U/week vs. (7068.48±1615.35) U/week,P<0.05].Serum erythropoietin concentration remained stable during the study in two groups. Conclusion ACEI can worsen anemia and reduce the efficacy of EPO in maintenance hemodialysis patients.