Tumor heterogeneity estimation for radiomics in cancer.

Radiomics is an emerging field of medical image analysis research where quantitative measurements are obtained from radiological images that can be utilized to predict patient outcomes and inform treatment decisions. Cancer patients routinely undergo radiological evaluations when images of various modalities including computed tomography, positron emission tomography, and magnetic resonance images are collected for diagnosis and for evaluation of disease progression. Tumor characteristics, often referred to as measures of tumor heterogeneity, can be computed using these clinical images and used as predictors of disease progression and patient survival. Several approaches for quantifying tumor heterogeneity have been proposed, including intensity histogram-based measures, shape and volume-based features, and texture analysis. Taking into account the topology of the tumors we propose a statistical framework for estimating tumor heterogeneity using clustering based on Markov random field theory. We model the voxel intensities using a Gaussian mixture model using a Gibbs prior to incorporate voxel neighborhood information. We propose a novel approach to choosing the number of mixture components. Subsequently, we show that the proposed procedure outperforms the existing approaches when predicting lung cancer survival.

Measuring the drafting alignment of patent documents using text mining.

How would an inventor, entrepreneur, investor, or patent examiner quantify the extent to which the inventive claims listed in a patent document align with patent specification? Since a specification that is poorly aligned with the inventive claims can render an invention unpatentable and can invalidate an already issued patent, an effective measure of alignment is necessary. We define a novel measure of drafting alignment using Latent Dirichlet Allocation (LDA). The measure is defined for each patent document by first identifying the latent topics underlying the claims and the specification, and then using the Hellinger distance to find the proximity between the topical coverages. We demonstrate the use of the novel measure for data processing patent documents related to cybersecurity. The properties of the proposed measure are further investigated using exploratory data analysis, and it is shown that generally alignment is positively associated with the prior patenting efforts as well as the tendency to include figures in a document.

The relationship between childhood trauma and adult psychosis in a UK Early Intervention Service: results of a retrospective case note study.

AIM: There is evidence that childhood trauma is a risk factor for the development of psychosis and it is recommended that childhood trauma is inquired about in all patients presenting with psychosis. This study aimed to determine the prevalence of childhood trauma in patients in the UK Early Intervention Service based on a case note review. METHODS: This is a retrospective case note study of 296 patients in an UK Early Intervention Service. Trauma history obtained on service entry was reviewed and trauma experienced categorized. Results were analyzed using crosstab and frequency analysis. RESULTS: The mean age of the sample was 24 years, 70% were male, 66% were White, and 23% Asian (ethnicity not documented in 11% of the sample). Approximately 60% of patients reported childhood trauma, 21% reported no childhood trauma, and data were not recorded for the remaining 19%. Among those reporting trauma, the prevalence of most frequently reported traumas were: severe or repeated disruption (21%), parental mental illness (19%), bullying (18%), absence of a parent (13%), and 'other' trauma (24%) - the majority of which were victimization events. Sixty-six percent of those reporting trauma had experienced multiple forms of trauma. CONCLUSION: A high prevalence of childhood trauma (particularly trauma related to the home environment or family unit) was reported. This is consistent with other studies reporting on trauma and psychosis. The main weakness of the study is a lack of a control group reporting experience of childhood trauma in those without psychosis. Guidelines recommend that all patients with psychosis are asked about childhood trauma; but in 19% of our sample there was no documentation that this had been done indicating the need for improvement in assessment.

Prazosin for treating sleep disturbances in adults with posttraumatic stress disorder: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: Posttraumatic stress disorder (PTSD) is a disorder with significant sleep morbidity and limited treatment options. Prazosin may constitute a novel management approach and has been tested recently in a number of trials. We conducted a meta-analysis to examine the effectiveness of prazosin for nightmares and other sleep disturbances in adults with PTSD. METHOD: A systematic review of databases for randomized, double-blind, placebo-controlled trials of adults diagnosed with PTSD and reporting sleep disturbances that were treated with prazosin was conducted in January 2015. No limitations were placed on language or year of publication. RESULTS: Six randomized controlled trials of prazosin for sleep disturbances in patients with PTSD were included (sample n=240). We found that prazosin was statistically significantly more effective than placebo in improving sleep quality [g=0.987, 95% confidence interval (CI): 0.324-1.651] and in reducing overall PTSD symptoms (g=0.699, 95% CI: 0.139-1.260) and sleep disturbances in particular (g=0.799, 95% CI: 0.391-1.234). CONCLUSIONS: Prazosin showed medium-to-large and statistically significant effects on PTSD symptoms in general and sleep disturbances in particular. While promising, results should be interpreted with caution given the limited total number of participants and the limitations induced by the majority of participants being male and noncivilian.