Validation of Risk Factors for Fecal Incontinence in Patients With Crohn's Disease

Background: Fecal incontinence has a great impact on daily life, and many patients are reluctant to report it. Objective: The purpose of this study was to estimate the prevalence of fecal incontinence in patients with Crohn's disease, validate risk factors, and relate outcome with quality of life. Design: The design was cross-sectional. Settings: The study was conducted at an academic tertiary center. Patients: Consecutive patients with Crohn's disease treated between 2003 and 2013 were included in this study. Main Outcome Measures: A questionnaire was sent out in October 2013 to evaluate perianal disease, current symptoms of fecal incontinence, and its impact on quality of life (Fecal Incontinence Quality of Life questionnaire). Risk factors were validated with univariate and multivariate analyses. RESULTS: The questionnaire was responded by 325 (62%) of 528 patients. Median age was 42 years (range, 18-91 y), 215 (66%) were women, and a diagnosis of Crohn's disease was established for a median period of 12 years (interquartile range, 6-21 y). Fecal incontinence was reported by 65 patients (20%). Fecal incontinence was associated with liquid stools (p = 0.0001), previous IBD-related bowel resections (p = 0.001), stricturing behavior of disease (p = 0.02), and perianal disease (p = 0.03). Quality of life (lifestyle, coping, depression, and embarrassment) was poor in patients with fecal incontinence, particularly in patients with more frequent episodes of incontinence. Limitations: There was no correction for disease activity in the multivariate regression analysis. Conclusions: The prevalence of fecal incontinence in a tertiary population with Crohn's disease is substantially higher than in the community-dwelling population. Considering the reduced quality of life in incontinent patients, active questioning to identify fecal incontinence is recommended in those with liquid stools, perianal disease, or previous (intestinal or perianal) surgery

All about activity injection: Threats, semantics, detection, and defense

Android supports seamless user experience by maintaining activities from different applications (apps) in the same activity stack. Although such close inter-app communication is essential in the Android framework, the powerful inter-app communication contains vulnerabilities that can inject malicious activities into a victim app's activity stack to hijack user interaction flows. In this article, we demonstrate activity injection attacks with a simple malware, and formally specify the activity activation mechanism using operational semantics. Based on the operational semantics, we develop a static analysis tool, which analyzes Android apps to detect activity injection attacks. Our tool is fast enough to analyze real-world Android apps in 6 seconds on average, and our experiments found that 1761 apps out of 129,756 real-world Android apps inject their activities into other apps' tasks. Moreover, we propose a defense mechanism, dubbed signature-based activity access control (SAAC), which completely prohibits activity injection attacks. The defense mechanism is general enough to keep the current Android multitasking features intact, and it is simple enough to be independent of the complex activity activation semantics, which does not increase activity activation time noticeably. With the extension of the formal semantics for SAAC, we prove that SAAC correctly mitigates activity injection attacks without any false alarms.