Hydrogen-bonded water clusters were formed with inert gases adsorbed to them in a strong molecular beam expansion. Upon single-photon ionization of such mixed clusters using VUV light, fragmentation of the substrate water cluster ion is markedly suppressed. Experimental evidence is presented, showing that the rapid evaporation of the inert gas from the newly formed water cluster ion efficiently removes internal energy on a time scale much faster than the usual fragmentation reactions present in pure water clusters, i.e., rates of fragmentation that are normally >109 s-1. This phenomenon is exploited to produce “unprotonated” water clusters, formally (H2O) n +. Using post source decay reflectron time-of-flight mass spectrometry, the structure of the “unprotonated” water cluster ions is experimentally determined for the first time. The structure determined, H3O+(H2O) k ·OH where the hydroxyl radical is found outside the first solvation shell of the charge, is consistent with recent ab initio calculations. This simple approach to the control of fragmentation in mass spectrometry appears to have promise in applications to other interesting polymeric samples, for example biopolymers.
We report full quantum-state-resolved spectra of highly vibrationally excited O2(X 3Σg−,v=26–31). In addition to providing high precision molecular constants for several new vibrational levels, we observe a local spectral perturbation of X 3Σg−(v=28). We present a deperturbation analysis of the observed spectra and assign the perturber to b 1Σg+(v=19). We predict a crossing between the b 1Σg+ and X 3Σg− state at an internuclear separation R=2.45±0.1 Å, somewhat further extended and higher in energy than the outer classical turning point of O2(X 3Σg−,v=28). Using the appropriate vibrational overlap integral, we are able to determine the spin–orbit interaction between these two electronic states, which is 200±20 cm−1 in the vicinity of the crossing. These results suggest that the collision dynamics of highly vibrationally excited O2(X 3Σg−) may involve excited potential surfaces. Furthermore, they imply that present theoretical approaches to the O4 problem, which use a single potential surface, may not be adequate. Possible implications regarding nonequilibrium models of stratospheric ozone formation and the dynamics of the O+O3→2O2 reaction are discussed.
Inflammation plays an important role in cancer progression. In this study, we aimed to investigate the prognostic value of the systemic inflammatory biomarkers in hepatocellular carcinoma (HCC) patients undergoing curative resection. Data from 271 HCC patients who underwent curative resection in Zhongshan Hospital between 2008 and 2011 were included. Kaplan-Meier survival analysis showed that gamma-glutamyltransferase (GGT) and lymphocyte-to-monocyte ratio (LMR) were significantly associated with overall survival(OS) and time to recurrence(TTR). We created a systemic inflammation score (SIS) basing on preoperative serum GGT and LMR. Low SIS was also significantly associated with increased OS and TTR. Univariate and multivariate analyses revealed the LMR, GGT and SIS were independent predictors for OS and TTR. The predictive ability of the SIS, as assessed by area under the receiver operating characteristic curve, was 0.682 (95% CI, 0.618-0.746) for OS, which was higher than GGT and LMR. In conclusion, low preoperative LMR and high preoperative GGT were associated with a poor prognosis in HCC patients after hepatectomy. Our results confirmed that the SIS qualifies as a novel prognostic predictor of HCC patients after hepatectomy.
Tumor of larger size and higher SUVmax predisposed patients to early onset of locoregional and distant progression. The nomogram developed in our study would be helpful in clinical decision-making and selection of patients who may benefit from more rigorous follow-up and aggressive systemic treatment plan.
Semaphorin 3A (SEMA3A), a secretory protein, is a founding member of the semaphorin family and functions in both the biological behavior of tumor cells and the modulation of tumor-associated macrophages. However, the role of SEMA3A in hepatocellular carcinoma (HCC) is still not well established. In the present study, we investigated the expression levels of SEMA3A in 80 HCC tissues and cell lines, using RT-qPCR, western blotting and immunohistochemistry. Expression profile analysis revealed that SEMA3A was significantly overexpressed in human HCC patients and positively correlated with the metastatic potential of HCC cells. Lentiviral transfection into PLC/PRF/5 and HCCLM3 cells was performed to stably upregulate and downregulate the expression of SEMA3A in HCC cells. Cell Counting Kit-8 (CCK-8), wound-healing and invasion assays revealed that SEMA3A promoted the proliferation and migration of HCC cells in vitro. Proteome profiler antibody microarray analysis revealed that overexpression of SEMA3A in HCC cells induced a significant increase in the expression levels of gelsolin-like capping protein (CapG), galectin-3, enolase 2 and epithelial cell adhesion molecule (EpCAM). Furthermore, the upregulation of SEMA3A in HCC cells promoted tumor growth and progression in an HCC mouse model. These results indicate that SEMA3A enhances CapG, galectin-3, enolase 2 and EpCAM expression to promote HCC progression and is a potential therapeutic target for HCC.
Background To investigate the potential impact of fractionation regimes and overall treatment time (OTT) on lymphopenia during definitive radiotherapy (RT) and its associations with patient outcomes in non-small cell lung cancer (NSCLC). Methods Subjects consisted of 115 patients who had received definitive chemoradiation therapy (CRT) with different doses and fractions for unresectable stage III NSCLC. Clinical and laboratory records were reviewed to assess the changes in total lymphocyte counts (TLCs) during definitive RT. The associations of the TLCs with the clinical and treatment features, and outcomes were analyzed. Results The median reduction of TLCs in the entire cohort was 1300 cells/μL (interquartile range [IQR], 950–1510 cells/μL). Of all patients, 63 (54.8%) experienced severe lymphopenia (SL) (TLC nadir < 500 cells/μL), which occurred at a median of the 5th week following RT initiation, not at the completion of RT or upon treatment with maximal doses. SL risk was increased over the first 5 weeks (odds ratio [OR] = 3.455, P = 0.007), after which, no increased risk was observed (OR = 0.562, P = 0.216). The median TLCs remained low and failed to recover to the initial normal values of their pre-RT level after 2 months of RT completion. Patients without SL exhibited significantly improved progression-free survival (hazard ratio [HR] = 0.544, P = 0.010) and overall survival (HR = 0.463, P = 0.011) after controlling for confounding variables in multivariate analyses. The incidence of SL was significantly lower (71.1% reduction in risk (OR = 0.289, P = 0.007)) in patients who received hypofractionated RT with an OTT within 4 weeks, compared to those who had an OTT of more than 4 weeks (32.1% vs 62.1%, P = 0.006). Multivariate analyses revealed that OTT within 4 weeks (OR = 0.322, P = 0.032) was significantly associated with a decreased risk of developing SL after controlling for confounding factors. Conclusions Hypofractionated RT was significantly associated with a decreased risk of SL and improved survival during definitive radiotherapy for unresectable stage III NSCLC. Electronic supplementary material The online version of this article (10.1186/s13014-019-1287-z) contains supplementary material, which is available to authorized users.
Lung cancer is a common malignant tumor with high morbidity and mortality. Here we compared the effects and outcome between central and peripheral stage I lung cancer using image-guided stereotactic body radiotherapy. From June 2011 to July 2013, a total of 33 patients with stage I lung cancer were enrolled. A total of 50 Gy in 10 fractions or 60 Gy in 10 fractions was delivered in the central arm (n ¼ 18), while 50 Gy in 5 fractions in the peripheral arm (n ¼ 15). Statistical analyses were performed using logistic regression analysis and Kaplan-Meier method. The mean follow-up time was 38.1 months. Three-month, 1-, 2-, and 3-year overall response rates were 66.7%, 83.3%, 61.1%, and 72.2% and 66.7%, 80%, 80%, and 80% in the central and peripheral arms, respectively. Three-year local control rates (94.4% vs 93.3%, P ¼ .854), regional control rates (94.4% vs 86.7%, P ¼ .412), and distant control rates (64.2% vs 61.7%, P ¼ .509) had no differences between the central and the peripheral arms. Grade 2 radiation pneumonitis was observed in 6 of 18 patients in the central arm and in 1 of 15 patients in the peripheral arm (P ¼ .92). Grade 2 radiation esophagitis was 5.7% in the central arm, while none occurred in the peripheral arm (P ¼ .008). Five (15.1%) of all patients felt slight fatigue during radiotherapy. Other major complications were not observed. In conclusion, helical image-guided stereotactic body radiotherapy for central stage I lung cancer is safe and effective compared to peripheral stage I lung cancer.
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