Bone remodeling in the Masquelet-induced membrane model of rat femur by modulation of H-type vessels by total flavonoids of rhizome drynariae / 中国组织工程研究

BACKGROUND:Several studies have found that the total flavonoids of rhizome drynariae can promote neovascularization in the induced membrane,improve the biological properties of the induced membrane,and accelerate bone remodeling in the induced membrane,but the related molecular mechanisms still need to be further explored. OBJECTIVE:To explore the effect of total flavonoids of rhizome drynariae on bone remodeling in rat femoral Masquelet-induced membrane model by regulating H-type blood vessels. METHODS:Thirty-six male Sprague-Dawley rats were stratified by body mass and then randomly divided into blank group,model group and traditional Chinese medicine group,with 12 rats in each group.A 4-mm femoral bone defect model was established in all the rats.Bone defects in the model group and traditional Chinese medicine group were filled with polymethylmethacrylate bone cement.At 6 weeks after modeling,the tail bone of the rats was implanted in the blank group,as well as in the other two groups after removal of bone cement.The traditional Chinese medicine group was given 157.5 mg/kg per day of total flavonoids of rhizome drynariae at 3 days after bone implantation,while the model and blank groups were given the same amount of saline by gavage until the 8th week after bone implantation.Bone graft samples were taken for relevant testing at 8 weeks after implantation. RESULTS AND CONCLUSION:X-ray films showed that in the blank group,the fracture line in the defect area was clear,and only a small amount of bone callus formed;in the model group,the bone defect area still existed,where discontinuous cortical bone was visible;in the traditional Chinese medicine group,the defect area was filled with newborn bone tissues,the bone marrow cavity and part of the cortical bone formed,and the fracture line disappeared.Micro-CT scans showed that the amount of new bone in the defect area was low in the blank group,the number of bone trabeculae in the defect area was significantly increased in the model group,and a large amount of new bone tissue was filled in the bone defect area in the traditional Chinese medicine group.Hematoxylin-eosin staining results showed that in the blank group,only a small amount of new bone formed in the defect area and the quality of osteogenesis was poor;in the model group,there was more new bone tissue in the defect area,but some fibrous connective tissues were interspersed within the bone tissue;and in the traditional Chinese medicine group,a large amount of new bone formed in the defect area and the quality of osteogenesis was the best.CD31/Emcn immunofluorescence double-labeling staining results showed that the number of H-type blood vessels in the newborn bone tissue in the bone defect area of the blank group was sparse and sparsely distributed;compared with the blank group,there were more H-type blood vessels in the bone tissue in the bone defect area of the model group,and the blood vessels were distributed in relatively regular strips;the number of H-type blood vessels in the bone defect area of the traditional Chinese medicine group was the highest and the blood vessels were densely distributed.To conclude,the total flavonoids of rhizoma drynariae can upregulate the expression of H-type blood vessels to enhance the angiogenic-osteogenic effect,improve the osteogenic efficiency of the rat femoral Masquelet induced membrane model,and promote bone remodeling.

Preparation of berberine-naringin dual drug-loaded composite microspheres and evaluation of their antibacterial-osteogenic properties / 中国修复重建外科杂志

OBJECTIVE@#To develop a drug-loaded composite microsphere that can simultaneously release the berberine (BBR) and naringin (NG) to repair infectious bone defects.@*METHODS@#The NG was loaded on mesoporous microspheres (MBG) to obtain the drug-loaded microspheres (NG-MBG). Then the dual drug-loaded compound microspheres (NG-MBG@PDA-BBR) were obtained by wrapping NG-MBG with polydopamine (PDA) and modifying the coated PDA with BBR. The composite microspheres were characterized by scanning electron microscopy, X-ray diffraction, specific surface area and pore volume analyzer, and Fourier transform infrared spectroscopy; the drug loading rate and release of NG and BBR were measured; the colony number was counted and the bacterial inhibition rate was calculated after co-culture with Staphylococcus aureus and Escherichia coli for 12 hours to observe the antibacterial effect; the biocompatibility was evaluated by live/dead cell fluorescence staining and cell counting kit 8 assay after co-culture with rat's BMSCs for 24 and 72 hours, respectively, and the osteogenic property was evaluated by alkaline phosphatase (ALP) staining and alizarin red staining after 7 and 14 days, respectively.@*RESULTS@#NG-MBG@PDA-BBR and three control microspheres (MBG, MBG@PDA, and NG-MBG@PDA) were successfully constructed. Scanning electron microscopy showed that NG-MBG@PDA-BBR had a rough lamellar structure, while MBG had a smooth surface, and MBG@PDA and NG-MBG@PDA had a wrapped agglomeration structure. Specific surface area analysis showed that MBG had a mesoporous structure and had drug-loading potential. Low angle X-ray diffraction showed that NG was successfully loaded on MBG. The X-ray diffraction pattern contrast showed that all groups of microspheres were amorphous. Fourier transform infrared spectroscopy showed that NG and BBR peaks existed in NG-MBG@PDA-BBR. NG-MBG@PDA-BBR had good sustained drug release ability, and NG and BBR had early burst release and late sustained release. NG-MBG@PDA-BBR could inhibit the growth of Staphylococcus aureus and Escherichia coli, and the antibacterial ability was significantly higher than that of MBG, MBG@PDA, and NG-MBG@PDA ( P<0.05). But there was a significant difference in biocompatibility at 72 hours among microspheres ( P<0.05). ALP and alizarin red staining showed that the ALP positive area and the number of calcium nodules in NG-MBG@PDA-BBR were significantly higher than those of MBG and NG-MBG ( P<0.05), and there was no significant difference between NG-MBG@PDA and NG-MBG@PDA ( P>0.05).@*CONCLUSION@#NG-MBG@PDA-BBR have sustained release effects on NG and BBR, indicating that it has ideal dual performance of osteogenesis and antibacterial property.

Systematic review of the effect of early feeding after cesarean section on gastrointestinal function recovery / 中国实用护理杂志

Objective To investigate the correlation between early postoperative diet and gastrointestinal function recovery after cesarean section. Methods A computerized search was performed through The Cochrane Library, PubMed, Embase, Web of Science, CBM, CNKI, Wanfang and VIP database for randomized controlled trails (RCTs) which studied the effects of early feeding after cesarean section on gastrointestinal function recovery. The analysis was performed after searching databases, assessing quality of included studies and extracting data using RevMan5.3. Results Totally 8 RCTs involving 1474 patients were included. It showed that early eating could shorten the recovery time of bowel sounds, the time of passage of flatus, the time of first defecation (P < 0.05), but there was no significant difference in the incidence of nausea and vomiting and abdominal distention (P > 0.05). Conclusion Early eating after cesarean section can shorten the recovery time of gastrointestinal function, but it does not show advantages in improving the incidence of nausea and vomiting and abdominal distention. It is necessary to carry out in-depth study to verify.

Application of flipped classroom teaching mode based on constructive theory in the course of Introduction to Nursing / 中国实用护理杂志

Objective To explore the effectiveness of flipped classroom teaching mode in the course of Introduction to Nursing. Methods Two classes of nursing students in grade 2014 were randomly assigned to the experimental group (n=34) and the control group (n=32) by lottery. Flipped classroom teaching mode and traditional teaching were used in the experimental group and the control group respectively. The final exam score, learning attitude, autonomous learning ability and critical thinking ability were compared between the two groups after the course. Results The final exam score of the experimental group was significantly higher than the control group (t=2.53,P < 0.05). Besides, the learning attitude (t=4.25,P<0.01), autonomous learning ability (t=11.45,P<0.01) and critical thinking ability (t=2.53,P < 0.05) were significantly higher than those of the control group and also improved significantly compared with the pre- teaching. Conclusion Flipped classroom teaching mode can effectively improve students’final exam score, learning attitude, autonomous learning ability and critical thinking ability.