Large bone defect repair is a difficult problem to be solved urgently in orthopaedic field, and the application of bone repair materials is a feasible method to solve this problem. Therefore, bone repair materials have been continuously developed, and have evolved from autogenous bone grafts, allograft bone grafts, and inert materials to highly active and multifunctional bone tissue engineering scaffold materials. In this paper, the related mechanism of bone repair materials, the application of bone repair materials, and the exploration of new bone repair materials are introduced to present the research status and advance of the bone repair materials, and the development direction is also prospected.
Objective To evaluate the effect of methylation determination about the peripheral plasma DNA in diagnose of hepatocellular carcinoma （HCC） and select the highly sensitive and specific methylated cancer suppressor genes. Methods Methylation-specific PCR （MSP） was used to detect the degree of methylation about SLIT2 and DAPK genes in peripheral plasma and associated cancer tissues of 34 patients with HCC confirmed by pathology, then analyzed their relationship to clinicopathologic feature. Results The positive rate of the promoter methylation of SLIT2 and DAPK genes in cancer tissues in 34 cases were 70.6% （24/34） and 79.4% （27/34）, while the relevant promoter methylation rate in plasma were 44.1% （15/34） and 50.0% （17/34） correspondingly. The sensitivity of detection of DNA methylation about SLIT2 and DAPK genes in plasma was 62.5% and 63.0%, respectively；both of the specificity for them were 100%. The negative predicted value was 52.6% and 41.2%, respectively；while both of the positive predicted value were 100%. There were no significant correlation between the clinicopathologic features and the methylation rate in cancer tissues and plasma （P＞0.05）. In plasma of patients whose AFP＜400 μg/L, the positive rate of combined detection of DNA methylation of SLIT2 and DAPK was 61.1% （11/18）. Conclusions The detection rate of DNA methylation of SLIT2 and DAPK genes in plasma is higher, and there is a significant correlation between the DNA methylation in HCC tissue and plasma, based on MSP method. DNA methylation in plasma, as an non-invasive method, could be used to diagnose HCC, especially for the patients whose AFP is negative. HBV infection may be only associate with DNA methylation of part gene.
With the in-depth research on bone repair process, and the progress in bone repair materials preparation and characterization, a variety of artificial bone substitutes have been fully developed in the treatment of bone related diseases such as bone defects. However, the current various natural or synthetic biomaterials are still unable to achieve the structure and properties of natural bone. Carbon nanotubes (CNTs) have provided a new direction for the development of new materials in the field of bone repair due to their excellent structural stability, mechanical properties, and functional group modifiability. Moreover, CNTs and their composites have broad prospects in the design of bone repair materials and as drug delivery carriers. This paper describes the advantages of CNTs related to bone tissue regeneration from the aspects of morphology, chemistry, mechanics, electromagnetism, and biosafety, as well as the application of CNTs in drug delivery carriers and reinforcement components of scaffold materials. In addition, the potential problems and prospects of CNTs in bone regenerative medicine are discussed.
ObjectiveTo explore the effects of silencing the expression of ubiquitin-conjugating enzyme E2T (UBE2T) gene on proliferation, apoptosis, migration and invasion abilities of A549 cells.MethodsA549 cells were cultured in vitro. Three sets of shRNA-UBE2T plasmid vectors (UBE2T-shRNA1 group, UBE2T-shRNA2 group, UBE2T-shRNA3 group) and shRNA-NC (shRNA-NC group) were constructed, respectively. A549 cells were transfected with lipofection transfection. The cells transfected with empty vector were enrolled as control (control group). The transfection efficiency was detected by RT-PCR. The effects of silencing the expression of UBE2T gene on biological behaviors (proliferation, apoptosis, migration, and invasion) of lung cancer A549 cells were detected by clone formation assay, flow cytometry, Transwell assay and scratch test. The expression of proliferation and apoptosis related proteins, and expression of PI3K/AKT signaling pathway proteins were detected by Western blot. ResultsAfter transfection, expression level of UBE2T mRNA in UBE2T-shRNA1 group, UBE2T-shRNA2 group and UBE2T-shRNA3 group was significantly down-regulated (all P<0.05), whose down-regulation was the most significant in UBE2T-shRNA3 group (P<0.05). Compared with control group and shRNA-NC group, clone formation rate, number of invasion A549 cells, scratch healing rate, Ki67 expression, PCNA expression, p-PI3K/PI3K ratio and p-AKT/AKT ratio were significantly decreased in UBE2T-shRNA3 group (P<0.05), while A549 apoptosis rate, Bax/Bcl-2 ratio and cleaved caspase-3/caspase-3 ratio were significantly increased (P<0.05). There were no significant differences in the above indexes between control group and shRNA-NC group (P>0.05). ConclusionsThe shRNA interfering with UBE2T is reliable to construct the model of A549 cells with stable low-expression UBE2T. Down-regulation of UBE2T expression can promote apoptosis of A549 cells, inhibit their proliferation, invasion and migration abilities. The mechanism may be related to inhibiting the activation of PI3K/AKT signaling pathway.
ObjectiveTo evaluate the impact of video-assisted thoracoscopic surgery (VATS) esophagectomy and routine operation on the short-term quality of life in patients with esophageal cancer. MethodsFrom January 2012 through January 2014, 157 esophageal cancer patients were classified into a VATS group (n=42) and a routine operation group (n=115) in our hospital. All patients in the two groups completed the Chinese versions of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (QLQ)-C30 and QLQ-OES18 at one, six and 12 months after operation separately. ResultsAt the end of 6, 12 months after operation, the evaluation on global health status was higher in the VATS group(68.8±12.3 vs. 62.7±13.7, P<0.05; 76.2±10.4 vs. 68.6±8.8, P<0.05). At the end of 1, 6, 12 months after operation, the scores of symptom pain were less significantly in the VATS group than those in the routine operation group (P<0.05). One month after operation, the score of active ability in the VATS group was higher (P<0.05). At the end of 6, 12 months after operation, the score of emotional function and social role in the VATS group was higher (P<0.05). At the end of 12 months after operation, the score of role function and cognitive function in the VATS group was also higher (P<0.05). ConclusionVATS is of better effect on improving short-term quality of life of esophageal cancer patients compared with routine operation.