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Accurate coregistration of computed tomography (CT) and magnetic resonance (MR) imaging can provide clinically relevant and complementary information and can serve to facilitate multiple clinical tasks including surgical and radiation treatment planning, and generating a virtual Positron Emission Tomography (PET)/MR for the sites that do not have a PET/MR system available. Despite the long-standing interest in multimodality co-registration, a robust, routine clinical solution remains an unmet need. Part of the challenge may be the use of mutual information (MI) maximization and local phase difference (LPD) as similarity metrics, which have limited robustness, efficiency, and are difficult to optimize. Accordingly, we propose registering MR to CT by mapping the MR to a synthetic CT intermediate (sCT) and further using it in a sCT-CT deformable image registration (DIR) that minimizes the sum of squared differences. The resultant deformation field of a sCT-CT DIR is applied to the MRI to register it with the CT. Twenty-five sets of abdominopelvic imaging data are used for evaluation. The proposed method is compared to standard MI- and LPD-based methods, and the multimodality DIR provided by a state of the art, commercially available FDA-cleared clinical software package. The results are compared using global similarity metrics, Modified Hausdorff Distance, and Dice Similarity Index on six structures. Further, four physicians visually assessed and scored registered images for their registration accuracy. As evident from both quantitative and qualitative evaluation, the proposed method achieved registration accuracy superior to LPD- and MI-based methods and can refine the results of the commercial package DIR when using its results as a starting point. Supported by these, this manuscript concludes the proposed registration method is more robust, accurate, and efficient than the MI- and LPD-based methods.

Interdecadal (10- to 100-year oscillation) moisture variations over the Monsoonal Asia (MA) is highly variable across regions and time, which are relatively less understood due to the shortness of the instrumental data of a few decades. In this study, comprehensive investigations on the spatiotemporal distributions of the interdecadal moisture variations over MA as well as their evolution from prior to the industrial era were conducted utilizing the tree-ring based drought reconstructions, i.e. the Monsoonal Asia Drought Atlas. Nine interdecadal moisture patterns in MA are identified using the self-organizing map based on the ensemble empirical mode decomposition. To further investigate these interdecadal moisture patterns, we aggregated the selected nine nodes into four patterns using a hierarchical clustering approach. Among them, Pattern 1 stands for a teleconnection between the Northeast MA and the Indian Peninsula, and Pattern 2 represents a dipole pattern between the Southern and Northern MA. We find that Pattern 1 may be linked with the dynamics of the Antarctic Oscillation that can modulate the strength of the Asian summer monsoon through meridional teleconnections. Pattern 2 is mainly driven by the elevated El Nino-Southern Oscillation variance and the zonal 'Silk Road Pattern' to bridge this interdecadal modulation.

LS177 is a novel inhibitor of mesenchymal epithelial transition (MET) that was used as an anticancer agent. The present study was to evaluate the absolute bioavailability of LS177 in rats. A rapid and sensitive ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS/MS) method has been developed and validated for the determination of LS177 in rat plasma. LS177 and internal standard (IS, LS410) were extracted from rat plasma samples by protein precipitation (PPT) for intravenous group and liquid-liquid extraction (LLE) procedure for oral group, then separated on a Phenomenex Kinetex XB-C18 (2.1 mm I.D. × 50 mm, 2.6 µm) using a mobile phase consisting of 0.1% formic acid in acetonitrile-0.1% formic acid water with a gradient elution program. The standard curves were linear over the ranges of 5.0–2000.0 ng · mL-1 for PPT and 1.0–200.0 ng · mL-1 for LLE. The mean recovery of LS177 was greater than 83.4% for PPT and not less than 88.5% for LLE, respectively. The intra- and inter-day accuracy and precision were within the acceptable limits of less than 15.0% at all concentrations. The validated method was successfully applied to the bioavailability study in rat plasma of LS177 and its absolute bioavailability was 25.37%. Copyright © 2015 John Wiley & Sons, Ltd.

There is a growing interest in the analysis of survival data with a cured proportion particularly in tumor recurrences studies. Biologically, it is reasonable to assume that the recurrence time is mainly affected by the overall health condition of the patient that depends on some covariates such as age, sex, or treatment type received. We propose a semiparametric frailty-Cox cure model to quantify the overall health condition of the patient by a covariate-dependent frailty that has a discrete mass at zero to characterize the cured patients, and a positive continuous part to characterize the heterogeneous health conditions among the uncured patients. A multiple imputation estimation method is proposed for the right-censored case, which is further extended to accommodate interval-censored data. Simulation studies show that the performance of the proposed method is highly satisfactory. For illustration, the model is fitted to a set of right-censored melanoma incidence data and a set of interval-censored breast cosmesis data. Our analysis suggests that patients receiving treatment of radiotherapy with adjuvant chemotherapy have a significantly higher probability of breast retraction, but also a lower hazard rate of breast retraction among those patients who will eventually experience the event with similar health conditions. The interpretation is very different to those based on models without a cure component that the treatment of radiotherapy with adjuvant chemotherapy significantly increases the risk of breast retraction.