OBJECTIVE: To investigate the effects of the Arg-Gly-Asp polypeptedes (RGD) peptides-modified porous tantalum surface on osteoblasts morphology and expressions of osteogenesis factors, and to evaluate RGD peptides promotes junctura ossium of tantalum-bone interface in vivo. METHODS: RGD peptides of different concentrations (1 g/L, 5 g/L, and 10 g/L) were loaded to porous tantalum slices with a diameter of 10 mm and a thickness of 3 mm by physical absorption. The 3rd generation of MG63 cells were co-cultured with tantalum and divided into 4 groups: Ta-cells (control) group, 1 g/L cells/Ta/RGD group, 5 g/L cells/Ta/RGD group, and 10 g/L cells/Ta/RGD group. Porous tantalum compo-sites and osteoblasts-tantalum interface were observed by scanning electron microscopy. The adhesion rate of osteoblasts was detected and immunocytochemistry was used to detect the expressions of filamentous actin (F-actin), osteocalcin (OC) and fibronectin (FN). RESULTS: The scanning electron microscope (SEM) revealed that osteoblasts distributed on the surface of porous tantalum and secreted extracellular matrix on outside and inner of micro-pores. The osteoblasts adhesion rate on porous tantalum modified with RGD was higher than that in the unmodified porous tantalum at the end of 24, 48, and 72 hours. The best adhesion effect was got in 5 g/L cells/Ta/RGD group at hour 48 [(68.07±3.80) vs. (23.40±4.39), P<0.05]. The results of immunocytochemistry showed that the expressions intensity of F-actin, OC and FN in osteoblasts on porous tantalum modified groups with RGD were stronger than that in the unmodified groups, and the expressions of 5 g/L cells/Ta/RGD group were significantly higher than those in the 10 g/L group and 1 g/L group [OC: (18.08±0.08) vs. (15.14±0.19), P<0.05; (18.08±0.08) vs. (14.04±0.61), P<0.05. FN: (24.60±0.98) vs. (15.90±0.53), P<0.05; (24.60±0.98) vs. (15.30±0.42), P<0.05. F-actin: (29.20±1.31) vs. (24.50±1.51), P<0.05; (29.20±1.31) vs. (16.92±0.40), P<0.05]. Correspondingly F-actin in osteoblasts was showed in longitudinal arrangement, and the expressions intensity was stronger than those OC and FN. CONCLUSION The RGD peptides is beneficial to enhance adhesion of osteoblast, spreading and reorganization of cytoskeleton on porous tantalum surface and improve the interface morphology, further promoting osteoblasts-tantalum conjunctive interface osseointegration.
Cell Adhesion ; Oligopeptides ; Osteoblasts/physiology* ; Osteogenesis ; Tantalum

OBJECTIVETo investigate the expression of CC-chemokine receptor 7(CCR7) in patients with multiple myeloma(MM) and its correlation with clinical features of MM.

METHODSThe level of CCR7 expression in bone marrow samples from 53 newly diagnosed MM patients was detected by flow cytometry(FCM). Statistical methods were used to analyze the correlation between CCR7 expression and clinical features, such as sex, age, M protein, peripheral blood cell count, biochemical indicators, plasma cell ratio of bone marrow, immunophenotype, osteopathy and extramedullary disease.

RESULTSThe plasma cells in 24 out of 53 cases(45.28%) expressed CCR7. The rate of extramedullary disease in CCR7 positive group was significantly higher than that in CCR7 negative group (29.17% vs 3.45%)(P<0.05).

CONCLUSIONThe expression of CCR7 in patients with MM is high, moreover this high expression correlates with extramedullary disease, thus CCR7 can be used as an effective indicator for prediction of extramedullary disease.

BACKGROUND: The preliminary study found that domestic porous tantalum is conducive to the early adhesion and proliferation of MG63 cells, which can be used as a scaffold material for bone tissue engineering. As an optimized product of platelet-rich plasma, platelet lysate is more suitable for bone induction in the bone repair. OBJECTIVE: To further investigate the effect of platelet lysate and domestic porous tantalum scaffold constructs on the proliferation of MG63 cells and expression of integrin β1 (ITGβ1)/Vinculin/F-actin signaling pathway based on our previous findings. METHODS: MG3 cells were cultured and inoculated onto domestic porous tantalum scaffolds with the addition of 3%, 5%, 7% and 10% platelet lysates. Then, 7% as the best volume fraction of platelet lysate was screened by cell counting kit-8 method. There were four experimental groups including blank group (normally cultured MG63 cells), platelet lysate group (MG63 cells were cultured in 7% platelet lysate), porous tantalum scaffold group (MG63 cells were cultured on the domestic porous tantalum scaffold), and combined group (MG63 cells were cultured with 7% platelet lysate and porous tantalum scaffold. Scanning electron microscope was used to observe the surface morphology of domestic porous tantalum and platelet lysate-porous tantalum scaffold-MG63 cell complex. Cell counting kit-8 method was used to detect the proliferation of MG63 cells. Real-time fluorescence quantitative PCR (qPCR), immunocytochemical staining and western blot were used to detect the expression of ITGβ1, Vinculin, F-actin in MG63 cells at mRNA and protein levels. RESULTS AND CONCLUSION: Under the scanning electron microscope, MG63 cells adhered well to the scaffold surface. Compared with the blank group, the proliferation of MG63 cells could be significantly promoted by either platelet lysate or porous tantalum scaffold (P < 0.05). Moreover, the proliferation of MG63 cells was significantly improved in the combined group compared with the other three groups (P < 0.05). Findings from qPCR, immunocytochemical staining and western blot showed the highest expression of ITGβ1, Vinculin, F-actin mRNA and protein in the combined group (P < 0.05). These results indicate that platelet lysate and the domestic porous tantalum scaffold can synergistically promote the proliferation of MG63 cells, and up-regulate the expression of ITGβ1, Vinculin and F-actin mRNA and protein. Activation of the ITGβ1/Vinculin/F-actin signaling pathway may contribute to the proliferation, adhesion and differentiation of MG63 cells.

Objective To explore the effect of improving clinical practice ability of nursing undergraduates via double evaluation.Methods From September 2015 to May 2016, 61 nursing undergraduates enrolled in 2012 to Guangzhou University of Chinese Medicine were selected by convenience sampling method and divided randomly according to their student number into experimental group (30 cases) and control group (31 cases). According to the double evaluation method adopted in the experimental group, clinical teaching scheme was modified dynamically. In the control group, clinical teaching was conducted according to clinical teaching scheme made by the university, with OSCE and evaluation form of clinical practice ability as tools for observer and self evaluation.Results Within the experimental group, both scores of observer evaluation in OSCE and scores of self evaluation in clinical practice behavior showed a trend of going up in phases (P<0.05). In comparison of observer evaluation in OSCE at the 9th month, scores of the experimental group were all higher than those in the control group in all dimensions except writing of nursing documents (P<0.05). In comparison of self evaluation in clinical practice behavior at the 9th month, scores of the experimental group were all higher than those in the control group in all dimensions except communication ability, slightly lower (P<0.05).Conclusions With the double evaluation method adopted, dynamically modified clinical teaching scheme according to phases can obviously improve clinical practice ability of nursing students.

OBJECTIVETo explore the expression of CC-chemokine Receptor 7 (CCR7) in adult acute leukemia patients, and to analyze the relationship of CCR7 expression with the clinical characteristics of patients.

METHODSThe expression of CCR7 in bone marrow samples from adult acute leukemia patients were detected by flow cytometry (FCM), the relationship of CCR7 expression with the clinical characteristics of patients such as sex, age, WBC count, blast cell ratio, CD56 expression, molecular biology, cell genetics, risk stratification, extramedullary infiltration was analyzed.

RESULTSThe expression rate of CCR7 in adult ALL and AML patients was 36.8% and 9.6%, respectively, and the expression level of CCR7 in ALL patients was higher than that in AML patients (P < 0.05). The extramedullary infiltration rate was 100% and 41.7 % for CCR7 positive and negative groups of ALL, respectively (P < 0.05). While the mean fluorescence intensity (MFI) in extramedullary infiltration group of ALL was higher than that in none-extramedullary infiltration group of ALL (50.00 ± 10.42 vs 18.14 ± 1.39), respectively (P < 0.05).

CONCLUSIONCCR7 is higher expressed in adult acute leukemia cells, moreover its expression rate in ALL is higher than that in AML, and the expression of CCR7 is related with extramedullary infiltration in ALL.

Adult ; Bone Marrow ; metabolism ; Flow Cytometry ; Humans ; Leukemia, Myeloid, Acute ; genetics ; metabolism ; Leukocyte Count ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; genetics ; metabolism ; Receptors, CCR7 ; genetics ; metabolism