ObjectiveTo evaluate the effect of using Schwann-like cells derived from human umbilical cord blood mesenchymal stem cells (hUCBMSCs) as the seed cells to repair large sciatic nerve defect in rats so as to provide the experimental evidence for clinical application of hUCBMSCs. MethodsFourty-five male Sprague Dawley (SD) rats in SPF grade, weighing 200-250 g, were selected. The hUCBMSCs were harvested and cultured from umbilical cord blood using lymphocyte separating and high molecular weight hydroxyethyl starch, and then was identified. The hUCBMSCs of 3rd generation were induced to Schwann-like cells, and then was identified by chemical derivatization combined with cytokine. The acellular nerve basal membrane conduit was prepared as scaffold material by the sciatic nerve of SD rats through repeated freezing, thawing, and washing. The tissue engineered nerve was prepared after 7 days of culturing Schwann-like cells (1×107 cells/mL) on the acellular nerve basal membrane conduit using the multi-point injection. The 15 mm sciatic nerve defect model was established in 30 male SD rats, which were randomly divided into 3 groups (10 rats each group). Defect was repaired with tissue engineered nerve in group A, with acellular nerve basal membrane conduit in group B, and with autologous sciatic nerve in group C. The nerve repair was evaluated through general observation, sciatic function index (SFI), nerve electrophysiology, weight of gastrocnemius muscle, and Masson staining after operation. ResultsThe hUCBMSCs showed higher expression of surface markers of mesenchymal stem cells, and Schwann-like cells showed positive expression of glia cell specific markers such as S100b, glial fibrillary acidic protein, and P75. At 8 weeks after operation, the acellular nerve basal membrane conduit had no necrosis and liquefaction, with mild adhesion, soft texture, and good continuity at nerve anastomosis site in group A; group B had similar appearance to group A; adhesion of group C was milder than that of groups A and B, with smooth anastomotic stoma and no enlargement, and the color was similar to that of normal nerve. SFI were gradually decreased, group C was significantly greater than groups A and B, group A was significantly greater than group B (P<0.05). The compound action potential could be detected in anastomotic site of 3 groups, group C was significantly greater than groups A and B, and group A was significantly greater than group B in amplitude and conduction velocity (P<0.05). Atrophy was observed in the gastrocnemius of 3 groups; wet weight's recovery rate of the gastrocnemius of group C was significantly greater than that of groups A and B, and group A was significantly greater than group B (P<0.05). Masson staining showed that large nerve fibers regeneration was found in group A, which had dense and neat arrangement with similar fiber diameter. The density and diameter of medullated fibers, thickness of myelinated axon, and axon diameter of group C were significantly greater than those of groups A and B, and group A was significantly greater than group B (P<0.05). ConclusionTissue engineered nerves from hUCBMSCs-derived Schwann-like cells can effectively repair large defects of the sciatic nerve. hUCBMSCs-derived Schwann-like cells can be used as a source of seed cells in nerve tissue engineering.
The resistance of non-small cell lung cancer (NSCLC) to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) has been brought into focus. COX-2 signal pathway was found to be closely related to EGFR signal pathway by recent researches, and there has been a growing interest to focus the researches on whether COX-2 pathway inhibition improves the efficacy of EGFR-TKIs in treating advanced NSCLC. In this review, we will illustrate recent advances of combined inhibition of EGFR and COX-2 signal pathways in NSCLC therapy.
ObjectiveTo systemically evaluate the efficacy and safety of cyclooxygenase-2 (COX-2) signal pathway inhibition in treating advanced non-small cell lung cancer (NSCLC). MethodsA systematic literature search in PubMed, EMbase, Cochrane Library, ASCO databases, CNKI and Wanfang database was conducted to identify relevant randomized controlled trials (RCTs) from the time of database establishment to June 2015. RCTs of COX-2 inhibitors treating advanced NSCLC were included. We assessed the methodology quality of the included studies by using Jadad's scale, and performed this meta-analysis by using stata12.0 software. ResultsTwelve RCTs involving three different COX-2 inhibitors with a total of 1 828 patients were identified including 8 studies of high quality and 4 studies of low quality. We found that COX-2 signal pathway inhibition could significantly increase overall response rate at RR=1.27 with 95%CI1.10 to 1.46 (P=0.001). While our present data could not confirm the efficacy of COX-2 inhibitors in improving progression-free survival (PFS) at HR=0.93 with 95%CI0.81 to 1.08 (P=0.334), overall survival (OS) at HR=0.95 with 95%CI0.84 to 1.08 (P=0.461), or one-year survival rate at RR=1.08 with 95%CI0.90 to 1.24 (P=0.29). As for toxicities, only increased risk of thrombocytopenia at RR=1.28 with 95%CI 1.03 to 1.85 (P=0.03) was observed in the patients treated with COX-2 inhibitors. ConclusionCOX-2 signal pathway inhibition is effective in improving the overall response rate of the patients with advanced NSCLC, and is well tolerated. Whether COX-2 signal pathway inhibition is effective in improving long-term survival of the patients with advanced NSCLC still needs to be confirmed via further clinical trials.
ObjectiveTo review the recent progress of the molecular targeted therapy for thyroid cancer. MethodsThe literatures of molecular etiology for thyroid cancer, mechanism and evaluation of targeted therapy via Medline and CHKD database were reviewed. ResultsSo far, four molecular targeted drugs (Sorafenib, Lenvatinib, Vandetanib, and Cabozantinib) have been approved for treatment of advanced thyroid cancer by FDA. They can mainly improve the patient's progression-free survival. Besides, several new molecular targeted drugs have accomplishedⅠphase or Ⅱ phase clinical trials. These drugs may be new options for treatment of advanced thyroid cancer in the future. ConclusionsMolecular targeted drugs have been the main therapeutic method for advanced thyroid cancer. However, we should invent more effective new drugs and investigate the drug combination to improve the therapeutic effect.
ObjectiveTo explore the surgical procedures for primary spontaneous pneumothorax without bullae. MethodsWe retrospectively analyzed the clinical data of 52 patients with primary spontaneous pneumothorax without bullae, who underwent surgical treatment in Second Affiliated Hospital of Kunming Medical University between January 2008 and January 2013. There were 46 males and 6 females, with mean average age of 23.2±4.3 years (ranged from 16 to 34 years). According to the different methods of intraoperative surgery, all patients were divided into three groups. The patients in a group Ⅰ (n=20) underwent video-assisted thoracoscope (VATS) selective apex of low energy electric coagulation treatment. The patients in a group Ⅱ (n=21) underwent VATS lung tip part of lung resection. The patients in a group Ⅲ (n=11) received VATS resection of the pleura. The clinical effectiveness among the three groups was compared. ResultsCompared with other two kinds of operation schemes,the leak duration(2.61±1.89 d vs. 4.90±3.20 d vs. 5.36±2.57 d, P=0.012), postoperative chest tube drainage time (3.67±2.13 d vs. 6.00±3.73 d vs. 7.03±2.58 d, P=0.003), postoperative length of hospital stay (4.95±2.16 d vs. 7.35±3.03 d vs. 8.61±2.67 d, P=0.002) and the recurrence rate (0.0% vs. 23.1% vs. 12.5%, P=0.021) of the patients with lung tip part resection of lung tissue by VATS were significantly lower. There were no statistically significant differences in the indicators of the patients with selective apex of low energy electric coagulation by VATS and those with pleural resection by VATS (P>0.05). ConclusionLung tip part of the lung tissue resection by VATS for primary spontaneous pneumothorax without bullae is better than VATS selective apical low energy coagulation treatment and VATS resection of the pleura both in the short and long-term efficacy.
ObjectiveTo investigate the effect of the estradiol hormones on biofilm formati on and structure of Staphylococcus epidermidis after breast implant surgery. MethodsThe concentration of Staphylococcus epidermidis strains ATCC35984 was adjusted to 1×107 CFU/mL or 1×108 CFU/mL, and the type strains were incubated on the surface of silica gel in 125 pmol/L estradiol suspensions to prepare bacterial biofilms model in vitro. After cultured in vitro for 4, 6, 12, 24, 48, and 72 hours, bacteria growth and biofilm formation ability were assessed by means of the XTT and crystal violet staining respectively. According to the above results, the bacterial suspension concentration was selected for experiments. The experimental concentration of Staphylococcus epidermidis ATCC35984 suspension and the concentrations of 50, 125, 250, 500 pmol/L estradiol suspensions were mixed with silica gel respectively to prepare biofilm model in vitro, no estradiol suspension served as control group. The experimental concentration of Staphylococcus epidermidis ATCC12228 suspension was used to prepare the same model in the negative control. After cultured in vitro for 4, 6, 12, 24, 48, and 72 hours, the same methods were used to assess the bacteria growth dynamics and biofilm forming ability, and the scanning electron microscope (SEM) was used to observe bacterial biofilm structure cultured on the surface of silica gel; the laser scanning confocal microscope (CLSM) was used to measure bacterial biofilm thickness on the surface of silica gel after 6, 12, and 24 hours. ResultsAccording to the results of semi quantitative detection of crystal violet stain and XTT methods, the bacterial suspension of 1×107 CFU/mL was selected for the experiment. XTT results indicated that the growth rates of ATCC12228 strain (at 4, 6, 12, 24, and 72 hours) and ATCC35984 strain (at 4, 6, 24, and 72 hours) in 125, 250, and 500 pmol/L estradiol were significantly faster than those in 0 and 50 pmol/L (P < 0.05). The growth rate of 500 pmol/L group was significantly faster than 125 and 250 pmol/L groups at 4, 6, and 72 hours (P < 0.05), and the growth rate of 250 pmol/L group was significantly faster than that of 125 pmol/L group at 72 hours (P < 0.05), but there was no significant difference between 0 and 50 pmol/L groups (P>0.05). At the same time point and same estradiol concentration, the growth rates showed no significant difference between 2 strains (P>0.05). Semi quantitative detection of crystal violet staining showed no biofilm formed in ATCC12228 strain in all estradiol concentration groups at different time points. In ATCC35984 strain, the biofilm was found at 4 hours and gradually thickened with time, reached the peak at 24 hours. After cultured for 4 and 6 hours, the biofilm of 0 pmol/L groups were significantly thicker than that of 125, 250, and 500 pmol/L groups (P < 0.05). At 12 hours, the 125 pmol/L group had the thickest biofilm, showing significant difference when compared with other groups (P < 0.05). The CLSM showed ATCC35984 biofilm thickness of 125, 250, and 500 pmol/L was significantly less than that of 0 and 50 pmol/L groups at 6 hours (P < 0.05), but difference was not significant between other groups (P>0.05). Then the thickness of the biofilm increased gradually, and the thickness of 125 pmol/L group was significantly larger than that of other concentration groups at 12 and 24 hours (P < 0.05). The SEM observation showed that the biofilm of 125 pmol/L group was denser and thicker than that of the other concentration groups at each time point. ConclusionHigh level estradiol can promote bacteria growth, biofilm formation, and biofilm maturity of Staphylococcus epidermidis.