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BACKGROUND:Micro-fracture surgery method is simple, easy to operate, which is an effective way to treat articular cartilage defects, but there are stil some problems such as regenerated fibrocartilage and regenerated cartilage degradation. Scholars have focused on the use of various methods to improve the micro-fracture effect on repairing cartilage defects. OBJECTIVE:To explore the effects of micro-fracture enhanced by autologous bone marrow mesenchymal stem cells extracellular matrix (aBMSC-dECM) scaffold for treating cartilage defects in minipig models. METHODS:Bone marrow was extracted from the minipigs and bone marrow mesenchymal stem cells were obtained. aBMSC-dECM membranes were col ected. Cross-linking and freeze-drying technology were used to make the three-dimensional porous aBMSC-dECM scaffold. Ful thickness cartilage defects, 2 mm in depth and 6 mm in diameter, were created on the femoral condyles and trochlea grooves of the two knees of the minipigs. The right knees were treated with micro-fracture as control and the left were treated with micro-fracture enhanced by aBMSC-dECM scaffold. Six months later, histological examination and Wakitani score were used to evaluate the cartilage regeneration, and glycosaminoglycans and DNA contents in the regenerative tissue were determined. RESULTS AND CONCLUSION:After 6 months, the tissue treated by micro-fracture enhanced by aBMSC-dECM scaffold got better surface and integrated with the surrounding cartilage. Safranin O and fast green staining and Masson staining showed that the regenerated cartilage of the left knee, with abundant matrix and dense bone trabeculae, was better than that of the right. Wakitani score of the left knee was higher than that of the right. Glycosaminoglycans content of the left knee was much more than that of the right, while the DNA content was lower in the left knee than the right knee. Better results were observed in the left knee undergoing micro-fracture enhanced by aBMSC-dECM scaffold, and improvements in the femoral condyles and trochlea grooves showed no differences.
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Objective To systematically evaluate the effects of compression stockings for preventing post-thrombotic syndrome after giant surgery in department of orthopaedics.Methods Randomized controlled trials about compression stockings were searched and analyzed no matter written in Chinese or English.The effects of compression stockings is determined by Meta-analysis with Review Manager 5.0.Results 4 papers were included in this research,among which,one was domestic,and another three were abroad.Heterogeneity was small when the data was merged,which suggested that compression stocking for preventing post-thrombotic syndrome was effective.Conclusions Compression stockings can be safely used to prevent post-thrombotic syndrome after giant surgery in department of orthopaedics.
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Objective To evaluate left ventricular (LV) myocardial contraction patterns and function by analyzing the distribution of peak value of segmental area strain and time sequence to the peak value.Methods 31 healthy subjects were involved.Real-time three dimensional full volume images of LV were acquired and analyzed with EchoPAC.LV volume and function parameters,as well as segmental and global systolic area strain and time to peak value were measured.The distribution of peak segmental area strain and time sequence to the peak value,interobserver and intraobserver variability of area strain parameters,as well as the relationship between global area strain and ejection fraction were evaluated.Results The peak segmental area strain was lower in the basic inferior and apical segments,and the peak value was reached earlier in the basic inferior,anteroseptal,and septal segments.Intraobserver and interobserver reliability of area strain parameters were good.Furthermore,a negative correlation was observed between global area strain and ejection fraction (r =-0.688,P =0.000).Conclusions The area strain measured by 4D strain can be used to evaluate the LV myocardial motion pattern and function.
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Objective To evaluate the patterns of intracardiac flow of left ventricle (LV) in patients with premature ventricular complexes (PVCs) from the right ventricular outflow tract (RVOT) by analyzing the vortex during isovolumetric contraction phase and the distribution rules of flow-time curves in each layer of LV.Methods Twenty-seven patients with frequent isolated PVCs from RVOT were involved and 25 healthy subjects as control.The color Doppler image of LV at apical four-chamber view was acquired.Vector flow mapping (VFM) was performed to assess the parameters of vortex during isovolumic contraction phase, including diameter (transverse and vertical diameter), velocity (maximal positive and negative velocity) and the number of vortex rings.Positive flow during systole and negative flow during diastole of LV in each layer were measured by flow-time curve.All values of patients with PVCs were recorded during sinus beats (PVC-S) and PVC (PVC-V) respectively.Results Significant differences were demonstrated in all parameters of vortex between the PVC-V and control subjects.And the flow-time curves disarrayed in PVC-V.The velocity of vortex in PVC-S was lower than that in control subjects.And the distribution pattern of flow-time curves in LV of PVC-S differed from that of control subjects.Conclusions Alternation of intracardiac fluid pattern in LV was demonstrated in patients with PVCs from RVOT during both sinus beats and PVC.VFM can be used to analyze the intracardiac flow field in normal and pathological electrical activation.
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The effects of hepatic stimulator substance (HSS) extracted from wealing rats on 4 kinds of cell lines are reported.In LW13 normal liver cell line, HSS significantly increased the incorporation of 3H-TdR into liver cells, but it had no effect oo K562 erythrokukcmia cell line and primary culture of rabbit epidermal cells, the latter can be stimulated by keratinocyte growth factor at a dose of 38?g/ml. Study of response of SMMC-7721 human hepatoma cell line to HSS revealed a dose-dependent decrease in 3H-TdR incorporation.