Objective To analyse the effect of recombinant endostatin on Treg, CD8 +T cells, tumor specific growth factor (TSGF) in peripheral blood of patients with advanced esophageal gastric junction adenocarcinoma and clinical efficacy observation.Methods 52 patients who were diagnosed with acute cerebral infarction in our hospital were collected.All patients were randomly divided into experimental group and control group, 26 cases in each group.The control group was given OLF chemotherapy, the experimental group was treated with OLF chemotherapy regimen combined with recombinant endostatin.21 days was 1 cycle, a total of 4 cycles.After treatment, the levels of Treg, CD8 +T cells, serum TSGF and clinical efficacy were detected in all patients.ResuIts After treatment, compared with control group,the peripheral blood Treg was significantly lower in the experimental group (P<0.05); the peripheral blood CD8 +T cells level in the experimental group was significantly higher (P<0.05);the serum TSGF level in the experimental group was significantly lower ( P<0.05 ); the effective of patients in the experimental group was higher ( P<0.05 ) . ConcIusion Recombinant endostatin can significantly reduce the levels of Treg and serum TSGF in patients with advanced esophageal gastric junction adenocarcinoma, improve the level of CD8 +T cells, and improve the efficiency of treatment, have guiding significance to clinical.

Objective To prepare the small intestinal submucosa (SIS) to be used as a scaffold in constructing engineered cardiac tissue. Methods Small intestinal submucosa of pig was treated with 0.25% trypsin and then 0.5% SDS for 24 hours each to obtain decellularized SIS. The obtained SIS was tested for its mechanical strength by stretching both horizontally and longitudinally with a material test machine. The cytotoxicity and histocompatibility of the material was also examined. Then the cardiomyocytes harvested from 3-day old neonatal rats were seeded on the SIS to construct engineered cardiac tissue sheets. These acquired engineered cardiac tissue sheets were immunohistochemically stained and observed with inversion microscope and transmission electromicroscope to evaluate their characteristics. Results SIS was decellularized completely. The mechanical capability of the decellularized SIS was satisfactory. Under 15% stretching, its strain and stress was nearly linear. SIS showed no cytotoxicity and inflammatory response. After 12 hours, the cardiomyocytes seeded in the SIS scaffold began to beat spontaneously. Two days later, the cardiomyocytes-SIS scaffold composite (engineered cardiac tissue sheet) began to beat spontaneously, and could beat spontaneously for 14 days. The constructed engineered cardiac tissue sheets consisted of layers of cardiomyocytes and with abundant extracellular collagen in the sheet. Conclusions SIS with good mechanical capability and biocompatibility has been prepared successfully, and then the engineered cardiac tissue has been constructed successfully based on the SIS scaffold.

Various surgical technologies have been developed to minimize the risk of the operation. With continuous water flow being the dissector, a relatively bloodless operation and a clear view for the operator can be obtained. When applied to the adventitia and the soft tissue adjacent to the vascular structure, it is satisfying and the vessel and ureter can be protected perfectly if ligated selectively. The operation time is also shorter than the routine one. So, further studies of this technology are necessary.

Objective To observe the adhesion of MC3T3-EI osteoblastic progenitor cells to the three-dimensional chitosan-decellularised-derma scaffolds,and evaluate the cytocompatibility of the scaffolds.Method The threedimensional chitosan-decellularised-derma scaffolds were prepared by the freeze-dtying method,the porosity,density and water absorption of which were measured.The microscopic morphology of the composite scaffolds was analyzed by the scanning electron microscopy(SEM).The MC3T3-E1 cells cultivated in vitro were seeded onto the composite scaffolds,and then co-cultured for 2,3,4 and 5 hours.At each time point,three specimens from each matrix were taken to determine the cell-adhesion rate and the best time of the cell-adhesion.The cells were seeded onto the composite scaffolds,and then co-cultured for 1,3,5,7,9,11 and 13 days.The MC3T3-E1 cells inside were evaluated with MTS test.The cell morphology was observed by the histological staining.The compression tests were performed using a Universal Testing Machine,at room temperature,as compared with no-cell-scaffolds.Results The three-dimensional chitosan-decellularised-derma scaffolds have high interval poroslty with the porosity(92.8%),the density(0.09796 g/ml)and the water absorption(2169±100)%.The cytocompatibility test shows that the seeded MC3T3-E1 cells can adhere to the scaffolds and proliferate.Conclusions The three-dimensional chitosan-decellularised-derma scaffolds have high interval porosity with the welldistributed diameter.The MC3T3-E1 cells are easy to adhere the scaffolds and proliferate which shows that the scaffolds have a good cytocompatibility.

Objective To study the effects of early mechanical strain magnitude on formation and differentiation of osteoclasts. Methods RAW 264.7 cells induced by macrophage colony-stimulating factors and osteoclast differentiation factors were subjected to 0, 1 000, 1 500, 2 000, 2 500 and 5 000 με mechanical straining for three days. The morphological changes, number of osteoclasts and proliferation of precursor cells were determined at day 7. The activity of the tartrate-reaistant acid phosphatase (TRAP) in the culture medium was detected at days 4 and 7. Results The number of osteoclasts was decreased in 2 500 με group, while it was increased in 5 000 με group. The proliferation of precursor cells was increased in 2 000 and 2 500 με group, while it was decreased significantly in 5 000 με group. There was no significant difference in the number of osteoclasts and proliferation of precursor cells among 1 000 με group, 1 500 με group and 0 με group. The activity of TRAP was decreased in 1 000, 1 500, 2 000, 2500 and 5 000 με groups at days 4 and 7 when compared with με group. Conclusions Early mechanical straining plays a direct role in formation and differentiation of osteoclasts. The high strain magnitude within physiological load inhibits osteoclast formation, while high strain magnitude beyond physiological load stimulates osteoclast formation. Low strain magnitude has nearly no impact on formation of osteoclasts. Early mechanical straining may inhibit differentiation of osteoclasts.

BACKGROUND: An important development orientation of osteomyelitis treating is to prepare a drug delivery system which has the characteristics of excellent biocompatibility, degradable, lengthen drug-released time, source sufficient, as well as use security. Alginate and chitosan can be used as drug delivery system due to the superordlnary biological properties. OBJECTIVE: To explore the feasibility and safety of alginate/chitosan incorporated vancomycin (VCM/ACA) as release carrier, in addition, to compare the difference from systematic injection. DESIGN, TIME AND SETTING: An in vivo drug concentration determination, matching grouping experiment. The experiment was performed at the animal and orthopedics laboratories, Affiliated Zhongshan Hospital of Dalian University from August 2008 to March 2009. MATERIALS: The alginate solution and vancocin solution was uniform mixed followed by adding CaCO_3 and citrate sodium solution, then the mixed liquor was prepared for vancocin-calcium alginate gel beads with microcapsule preparation instrument. After that, the vancocin-calcium alginate gel beads were reacted with chitosan/vancocin mixed liquor and cellulose acetate to prepare for VCM/ACA release carrier. METHODS: Forty rabbits were prepared for middle of left femur bone defect models, and then randomized divided into 2 groups, with 20 animals in each group. In the local medication group, VCM/ACA release carrier was inlaid to the defects. In the systemic administration group, rabbits were intravenous injected 10% vancocin (10 mg/kg). MAIN OUTCOME MEASURES: The drug concentrations in the serum and bone tissues of the local medication group was detected by high performance liquid chromatograph at hours 0.5, 1, 6, 24, 72 and weeks 1, 2 after operation. In the systemic administration group, the drug concentrations in the serum, bone and muscle tissues were measured at minute 10 and hours 0.5, 1, 6, 24, and 72 after operation. In addition, histological sections of body tissues were prepared to look for signs of systemic toxicity of the implants. RESULTS: The serum drug concentrations of the systemic administration group were obvious greater than the local medication group at each time points prior to 24 hours, which less than the local medication group at hour 24. The drug concentration in bone and muscle tissues of local medication group were significant greater than the systemic administration group at different time points, which sustained for at least 2 weeks, while serum concentration in the systemic administration group was much lower than minimum inhibitory concentration after 24 hours. However, no multiple tissues revealed histological evidence of toxicity. CONCLUSION: There has feasibility and safety in vivo in course of ALM/VCM release carrier, which has superior effect to systemic administration.

BACKGROUND: Seed cell exerting its function is required to depend on the extracellular matrix in tissue engineering, so that biocompatible material is important to be selected. OBJECTIVE: To prepare a novel composite scaffolds of chitosan/collagen/nano-hydroxyapatite (HA-CS/Col/nHAP) and to optimize the technology of tissue engineered-stents according to the circumstances of cell adhesion.METHODS: Chitosan was modified by hyaluronate acid. The structure was observed by differential scanning calorimetry and the Fourier transformed infrared spectroscopy. Three composites of HA-CS/Col/nHAP according to different ratio of chitosan and collagen solution (1: 2; 1: 1 and 2: 1) were prepared. The composite scaffolds were co-cultured with osteoblast MC3T3-E1, and the proliferation and cell growth curve were measured by CCK-8 method. RESULTS AND CONCLUSION: Hyaluronic acid and chitosan were crosslinked with amide linkage. Pore size was on the range from 50 μm to 250 μm. Porosity was increased with increased collagen level and elastic modulus, but density was reduced. Increased collagen content was beneficial for cell adhesion and proliferation on stent in the primary phase of cell co-culture. However, from day 10, no significant difference was determined among three samples. At the beginning of cell culture, cells adhered to the airspace insides the composite scaffolds. In the following days, cells grew in a colony manner, and cell-cell junction could be easily observed. These indicate that HA-CS/Col /nHAP composite scaffolds can improve the adhesion and proliferation of osteoblast. The ratio of chitosan to collagen volume at 1: 1 was optimal.

Objective To prepare a novel bioactive and degradable scaffold with mineralized collagenpolyose based composite by biomimetic synthesis for bone tissue engineering and explore the compatibility of osteoblast culturing on the scaffold.Methods Using the cross-linking product of collagenⅠ and sodium hyaluronate as the template,the calcium phosphate was deposited on it to produce a mineralized composite.The 3-D porous scaffolds were prepared by liquid phase separation after the mineralized composite combining with polylactic acid (PLA) and NaCl.The materials and scaffolds were investigated by x-ray diffraction (XRD),scanning electronic microscopy (SEM) and universal testing machine.In addition,inverted microscope,fluorescence microscope,SEM,Cell Counting Kit-8 assay and alkaline phosphatase (ALP) assay were introduced to analyze the growth,function and compatibility(morphology,proliferation and differentiation ) of osteoblast-like cell on the scaffolds.Results The degree of hydroxyapatite (HA) crystals in the composite was low and the size was tiny,which were similar to that of nature bone.The SEM micrographs showed that the scaffolds possessed 82% of porosity and the pore size was about 200 μm to 650 μm.Cells on the scaffolds spread well and presented a high proliferation rate and differentiation level.Conclusion The novel scaffolds are simiar to nature cancellous (spongy) bone both on structure and in property and might be used as one of the optimal scaffolds material for bone tissue engineering.

Objective To evaluate the safety and accuracy in treating the avascular necrosis of femoral head (ANFH) with computer navigated core decompression and bone marrow stream cell transportation and to guide the clinical treatment. Method Within the prospective study, 36 patients suffered ANFH (ARCO Ⅰ - Ⅱ ) and treated with computer navigated core decompression and bone marrow stream cell transportation were studied. The operating time, blood loss, x ray exposure, preoperative and 6 week postoperative Harris score and imaging evaluation were recorded and compared with conventional core decompression and bone marrow stream cell transportation. Results There were no obvious difference between the two groups in imaging evaluation, operating time and blood loss ( P ＞ 0. 05 ). There were statistical difference between the two groups in x ray exposure and 6 week postoperative Harris score [ (4. 1 ± 1.8 ) s,(13.6±3.2)s,P ＜0. 01,and89.4±10. 1,83.1±10. 5, P ＜0.01]. Conclusion Computer navigated core decompression and bone marrow stream cell transportation have good security and precision in treating early stage ANFH.

Extracellular matrix (ECM) keeps cell's shape, protects and nourishes cells; it plays a great role in cell proliferation and differentiation. Therefore, ECM is very important in cell and tissue engineering. In this study, after primary mouse osteoblasts and fibroblasts maintained at confluence in vitro were removed, their ECM coated on cell culture plate was prepared, and bone morphogenetic proteins 2 (BMP-2) was detected in the osteoblasts ECM. MC3T3-E1 preosteoblasts cells were seeded on cell culture plates covered with fibroblasts ECM and osteoblasts ECM respectively. The proliferative activity of the cells cultured on fibroblasts ECM was higher than that on osteoblasts ECM and the control group. The alkaline phosphatase activity, relative protein levels of BMP-2 and osteopontin, secreted calcium of the cells cultured on osteoblasts ECM were all the highest. The results indicate that the two different ECMs produced in vitro had different bioactivities, the fibroblasts ECM coated on cell culture plates could accelerate MC3T3-E1 cells proliferation, and the osteoblasts ECM could promote cells osteogenic differentiation.
3T3 Cells ; Alkaline Phosphatase ; metabolism ; Animals ; Animals, Newborn ; Bone Morphogenetic Protein 2 ; metabolism ; Calcium ; metabolism ; Cell Differentiation ; physiology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Extracellular Matrix ; metabolism ; physiology ; Mice ; Osteoblasts ; cytology ; Osteopontin ; metabolism