Electron acceleration with improved Stochastic Differential Equation method: cutoff shape of electron distribution in test-particle limit

We develop a method of stochastic differential equation to simulate electron acceleration at astrophysical shocks. Our method is based on It\^{o}'s stochastic differential equations coupled with a particle splitting, employing a skew Brownian motion where an asymmetric shock crossing probability is considered. Using this code, we perform simulations of electron acceleration at stationary plane parallel shock with various parameter sets, and studied how the cutoff shape, which is characterized by cutoff shape parameter $a$, changes with the momentum dependence of the diffusion coefficient $\beta$. In the age-limited cases, we reproduce previous results of other authors, $a\approx2\beta$. In the cooling-limited cases, the analytical expectation $a\approx\beta+1$ is roughly reproduced although we recognize deviations to some extent. In the case of escape-limited acceleration, numerical result fits analytical stationary solution well, but deviates from the previous asymptotic analytical formula $a\approx\beta$.Comment: corrected typos, 10 pages, 4 figures, 2 tables, JHEAp in pres

Pathological Vascular Invasion and Tumor Differentiation Predict Cancer Recurrence in Stage ia Non–Small-Cell Lung Cancer After Complete Surgical Resection

Introduction:The appropriate therapeutic strategy and postoperative management for patients with stage IA non–small-cell lung cancer (NSCLC) still remain a matter of debate because of the prognostic heterogeneity of this population, including the risk of cancer recurrence. The objective of the current study was to identify the clinicopathological factors that affect overall prognosis and cancer recurrence of stage IA NSCLC.Methods:We reviewed the data of 532 patients in whom complete resection of stage IA NSCLC had been performed. Overall survival and recurrence-free proportion (RFP) were estimated using the Kaplan–Meier method. RFP was estimated from the date of the primary tumor resection to the date of the first recurrence or last follow-up. We performed univariate and multivariate analyses to determine the independent prognostic factors.Results:On multivariate analyses, three variables were shown to be independently significant recurrence risk factors: histological differentiation (hazard ratio [HR] = 1.925), blood-vessel invasion (HR = 1.712), and lymph-vessel invasion (HR = 1.751). On subgroup analyses combining these risk factors, the 5-year RFP was 91.3% for patients with no risk factors, 79.5% for those with either poorly differentiated carcinoma or vascular invasion, (p < 0.001 for both), and 62.9% for those with both poorly differentiated carcinoma and vascular invasion (p = 0.068).Conclusion:These results indicated that vascular invasion and tumor differentiation have a significant impact on the prediction of cancer recurrence in patients with stage IA NSCLC. Patients with these predictive factors of recurrence may be good candidates for adjuvant chemotherapy

Prognostic Impact of Number of Resected and Involved Lymph Nodes at Complete Resection on Survival in Non-small Cell Lung Cancer

BackgroundLymph node (LN) status is a major determinant of stage and survival in patients with lung cancer. In the 7th edition of the TNM Classification of Malignant Tumors, the number of involved LNs is included in the definition of pN factors in breast, stomach, esophageal, and colorectal cancer, and the pN status significantly correlates with prognosis.MethodsWe retrospectively investigated the prognostic impact of the number of resected LNs (RLNs) and involved LNs in the context of other established clinical prognostic factors, in a series of 928 consecutive patients with non-small cell lung cancer (NSCLC) who underwent complete resection at our institution between 2000 and 2007.ResultsThe mean number of RLNs was 15. There was a significant difference in the total number of RLNs categorized between less than 10 and ≥10 (p = 0.0129). Although the incidence of LN involvement was statistically associated with poor prognosis, the largest statistically significant increase in overall survival was observed between 0 to 3 and ≥4 involved LNs (hazard ratio = 7.680; 95% confidence interval = 5.051–11.655, p < 0.0001). On multivariate analysis, we used the ratio between the number of involved LNs and RLNs. The number of RLNs was found to be a strong independent prognostic factor for NSCLC (hazard ratio = 6.803; 95% confidence interval = 4.137–11.186, p < 0.0001).ConclusionComplete resection including 10 or more LNs influenced survival at complete NSCLC resection. Four involved LNs seemed to be a benchmark for NSCLC prognosis. The number of involved LNs is a strong independent prognostic factor in NSCLC, and the results of this study may provide new information for determining the N category in the next tumor, node, metastasis classification

Management of Multiple Primary Lung Cancer in Patients with Centrally Located Early Cancer Lesions

BackgroundPatients with centrally located early lung cancer (CLELC) are often heavy smokers with a considerably high risk of multiple primary lung cancer (MPLC) lesions; treatment strategies for such patients must preserve the cardiopulmonary function.MethodsBetween July 2004 and July 2008, patients with CLELC underwent photodynamic therapy (PDT) using NPe6, second-generation photosensitizer at Tokyo Medical University Hospital. Among these patients, we retrospectively analyzed MPLC, which was treated by surgery plus PDT or PDT alone and examined the effectiveness of PDT, and we propose a treatment strategy for patients with MPLC.ResultsA total of 64 patients with CLECL received NPe6-PDT, and MPLCs were found in 22 patients (34.4%) using sputum cytology and a bronchoscopical examination using autofluorescence bronchoscopy. Among these 22 patients, 10 patients underwent surgery for primary lung cancer and underwent NPe6-PDT for the treatment of secondary primary CLELC, one patient underwent PDT for CLELC as a primary lesion followed by an operation for peripheral-type lung cancer as a secondary primary lesion, and 11 patients underwent PDT alone for MPLC lesions (28 lesions) that were roentgenographically occult lung cancers. Among these 22 patients with MPLC including peripheral-type lung cancers, which were resected by surgery, all 39 CLELC lesions exhibited a complete response after PDT, and all patients were alive.ConclusionsFor patients with lung cancer with a long-term history of smoking, careful follow-up examinations after surgical resection are needed considering the incidence of metachronous primary lung cancers. PDT can play an important role for the treatment strategy for MPLC

Comparison of ESD and Conventional Methods in Single Cell Spray

Various inorganic ions are related to activity in a cell. Behavior of biological activity is traditionally observed by using optical microscope and/or MALDI. However, higher spatial resolution imaging technique is needed to observe organelles in a cell. In such cases, fixation in vacuum becomes quite big problem to maintain original structure in a cell. Rapid freezing seems one of the promising methods. But single cells cannot be treated as section. In this study, we devised a new rapid freezing method by combining electro-spray deposition and metal-touch freezing. In this method, individual cell is sprayed with a droplet emitted from the electro-spray tip, and each cells impact on the cooled metal surface, then frozen rapidly