Lung cancer causes serious health problems. Clinical diagnosis of lung cancer relies on histopathological evalution of tissue specimen. However, extensive knowledge of the metabolic biochemistry of tumors can potentially provide important information for accurate diagnosis of lung cancer. High resolution magic-angle spinning NMR spectroscopy has emerged and be widely acknowledged as an excellent tool in investigating tissue metabolism. Moreover, the combination of high resolution magic-angle spinning NMR technique and multivariate data analysis has become an important metabonomics platform for studying the intact biological tissues. This study reported the metabonomic characteristics of 51 lung tissues from 17 patients with lung cancer using the high resolution magic-angle spinning 1H NMR spectroscopy and the multivariate data analysis methods including principal component analysis and orthogonal partial least squares-discriminant analysis. Clear differences among the metabonomic characteristics of lung cancer tissues at various sites were disclosed. Compared with the adjacent noninvolved tissues, the lung cancer tissues had significantly high levels of aspartate, phosphocholine, glycerophosphocholine and lactate but significantly low levels of glucose and valine. Furthermore, significantly positive (or negative) correlations were observed between the levels of some metabolites such as lactate, fatty acids, valine, phosphocholine, and glycerophosphocholine. Magn Reson Med 66:1531-1540,
The express freight trains are being developed rapidly in China, and they have the characteristics of smaller axle weight and higher velocity compared with the normal freight trains. The running safety of the trains on the bridge is significantly affected by the strong crosswind, which may cause overturning accidents in severe cases. The wind tunnel tests of the express freight train–bridge scale models are conducted in this study to investigate the aerodynamic characteristics of the vehicles when they run on the box girder bridge and the double-deck steel truss bridge. The uniform flow and the atmospheric boundary layer (ABL) flow are constructed respectively to compare the differences of the aerodynamic characteristics under different flow fields. The test results show that the distribution of pressure coefficients on the car body is related to the type of test flow field and bridge, and it is also greatly affected by the running position on the bridge as well as the location of the vehicle in the train. The magnitude of the side force coefficients and the rolling moment coefficients of the vehicle on the steel truss bridge are less than those on the box girder bridge. The influence of the flow field type on the side force coefficients of the middle vehicle is slightly larger than that of the tail vehicle, but it has a low correlation with the type of bridge. When the vehicle is on the windward track of the bridge, the values of power spectral density (PSD) of the side force are larger than those on the leeward track. The results provide data support for the running safety research of the express freight trains and reference for the railway vehicle wind tunnel test method.
PurposeBridge to elective surgery (BTS) using self-expanding metal stents (SEMS) is a common alternative to emergency surgery (ES) for acute malignant left-sided colonic obstruction (AMLCO). However, the study regarding long-term impact of BTS is limited and unclear.MethodsA multicenter observational study was performed at three hospitals from April 2012 to December 2019. Propensity score matching (PSM) was introduced to minimize selection bias. The primary endpoint was overall survival. The secondary endpoints included surgical approaches, primary resection types, total stent related adverse effects (AEs), surgical AEs, length of hospital stay, 30-day mortality and tumor recurrence.Results49 patients in both BTS and ES group were matched. Patients in the BTS group more often underwent laparoscopic resection (31 [63.3%] vs 8 [16.3%], p<0.001), less likely to have a primary stoma (13 [26.5%] vs 26 [53.1%], p=0.007) and more often had perineural invasion (25 [51.0%] vs 13 [26.5%], p=0.013). The median overall survival was significantly lower in patients with stent insertion (41 vs 65 months, p=0.041). 3-year overall survival (53.0% vs 77.2%, p=0.039) and 5-year overall survival (30.6% vs 55.0%, p=0.025) were significantly less favorable in the BTS group. In the multivariate Cox regression analysis, stenting (hazard ratio(HR)= 2.309(1.052-5.066), p=0.037), surgical AEs (HR=1.394(1.053-1.845), p=0.020) and pTNM stage (HR=1.706(1.116-2.607), p=0.014) were positively correlated with overall survival in matched patients. ConclusionsSelf-expanding metal stents as “a bridge to surgery” is associated with more perineural invasion, higher recurrence rate and worse overall survival in patients with acute malignant left-sided colonic obstruction compared with emergency surgery.
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