Definitions, pathophysiology, and epidemiology of acute cholangitis and cholecystitis: Tokyo Guidelines

This article discusses the definitions, pathophysiology, and epidemiology of acute cholangitis and cholecystitis. Acute cholangitis and cholecystitis mostly originate from stones in the bile ducts and gallbladder. Acute cholecystitis also has other causes, such as ischemia; chemicals that enter biliary secretions; motility disorders associated with drugs; infections with microorganisms, protozoa, and parasites; collagen disease; and allergic reactions. Acute acalculous cholecystitis is associated with a recent operation, trauma, burns, multisystem organ failure, and parenteral nutrition. Factors associated with the onset of cholelithiasis include obesity, age, and drugs such as oral contraceptives. The reported mortality of less than 10% for acute cholecystitis gives an impression that it is not a fatal disease, except for the elderly and/or patients with acalculous disease. However, there are reports of high mortality for cholangitis, although the mortality differs greatly depending on the year of the report and the severity of the disease. Even reports published in and after the 1980s indicate high mortality, ranging from 10% to 30% in the patients, with multiorgan failure as a major cause of death. Because many of the reports on acute cholecystitis and cholangitis use different standards, comparisons are difficult. Variations in treatment and risk factors influencing the mortality rates indicate the necessity for standardized diagnostic, treatment, and severity assessment criteria

Context Relevance Assessment and Exploitation in Mobile Recommender Systems

In order to generate relevant recommendations, a context-aware recommender system (CARS) not only makes use of user preferences, but also exploits information about the specific contextual situation in which the recommended item will be consumed. For instance, when recommending a holiday destination, a CARS could take into account whether the trip will happen in summer or winter. It is unclear, however, which contextual factors are important and to which degree they influence user ratings. A large amount of data and complex context-aware predictive models must be exploited to understand these relationships. In this paper, we take a new approach for assessing and modeling the relationship between contextual factors and item ratings. Rather than using the traditional approach to data collection, where recommendations are rated with respect to real situations as participants go about their lives as normal, we simulate contextual situations to more easily capture data regarding how the context influences user ratings. To this end, we have designed a methodology whereby users are asked to judge whether a contextual factor (e.g., season) influences the rating given a certain contextual condition (e.g., season is summer). Based on the analyses of these data, we built a context-aware mobile recommender system that utilizes the contextual factors shown to be important. In a subsequent user evaluation, this system was preferred to a similar variant that did not exploit contextual information

Natural history of gallstones in non-insulin-dependent diabetes mellitus - A prospective 5-year follow-up

This prospective study was undertaken to assess the natural history of gallstones in patients with non-insulin-dependent diabetes. Four hundred forty outpatients with diabetes mellitus were studied; 81 of these had gallstones diagnosed by ultrasound. On the basis of the information they gave, they were divided into two groups: A, asymptomatic; and B, symptomatic (previous episode(s) of biliary pain) at recruitment. Five years after diagnosis, the patients were recalled and questioned about their symptoms. Three of 81 could not be traced and eight had died from diseases not related to gallstones. Seventy were finally evaluated, 47 belonging to group A, 23 to group B. The cumulative percentage of initially asymptomatic patients who presented with biliary pain or complications during the follow-up was 14.9% (4.2% for complications). Of group A patients, 17% underwent cholecystectomy (one prophylactic, six elective and two emergency). One patient (2.1%) died after operation of obstructive jaundice. Of group B patients, 47.8% had biliary symptoms or complications (8.7% cholecystitis); 21.7% were operated (17.4% elective, 4.3% emergency cholecystectomy). Since few patients with asymptomatic gallstones and non-insulin-dependent diabetes mellitus develop pain or complications over time, prophylactic cholecystectomy is probably not advisable. © 1994 Plenum Publishing Corporation