Cholestasis: the ABCs of cellular mechanisms for impaired bile secretion--transporters and genes

Nutrition assessment and support in children with end-stage liver disease

Malnutrition is a treatable complication in children with end-stage liver disease (ESLD). Biliary atresia and other cholestatic disorders are the most frequent cause of ESLD in children. No single variable provides adequate information about nutrition status, yet effective nutrition support is the one intervention known to improve pre- and posttransplant outcomes. A proactive approach consisting of screening anthropometry interpreted using appropriate growth references, recognition of clinical manifestations associated with micronutrient deficiency, and timely aggressive nutrition support is of a paramount importance to maximize anabolism and optimize outcomes. This article presents the principles of nutrition assessment, intervention, and monitoring in children with ESLD.

Epidemiology and risk factors for gallstone disease: has the paradigm changed in the 21st century?

Gallstone disease is common and costly, creating over 700,000 cholecystectomies annually. Its complications consume approximately $6.5 billion in the United States. Surveys using noninvasive ultrasonography have identified its true prevalence and the associated risk factors. In developed countries, at least 10% of white adults harbor cholesterol gallstones; women have twice the risk, and age further increases the prevalence in both sexes. Gallstones reach epidemic proportions in the North and South American Indian populations, accompanied by an increased risk for gallbladder cancer. In contrast, the rate in sub-Saharan Africa and Asia is quite low. Obesity, a major risk factor, likely relates to insulin resistance (the metabolic syndrome). Evolution and circumstance in American Indians may have ironically selected those with "thrifty" genes that conserve energy. Our abundant access to food places us at the increased risk of obesity and cholelithiasis. The general rise in obesity in many countries raises the specter of heightened disease, best identified by epidemiologic studies.

Epidemiology and risk factors for gallstone disease: has the paradigm changed in the 21st century?

Gallstone disease is common and costly, creating over 700,000 cholecystectomies annually. Its complications consume approximately $6.5 billion in the United States. Surveys using noninvasive ultrasonography have identified its true prevalence and the associated risk factors. In developed countries, at least 10% of white adults harbor cholesterol gallstones; women have twice the risk, and age further increases the prevalence in both sexes. Gallstones reach epidemic proportions in the North and South American Indian populations, accompanied by an increased risk for gallbladder cancer. In contrast, the rate in sub-Saharan Africa and Asia is quite low. Obesity, a major risk factor, likely relates to insulin resistance (the metabolic syndrome). Evolution and circumstance in American Indians may have ironically selected those with "thrifty" genes that conserve energy. Our abundant access to food places us at the increased risk of obesity and cholelithiasis. The general rise in obesity in many countries raises the specter of heightened disease, best identified by epidemiologic studies.

The role of investigative molecular toxicology in early stage drug development

Molecular toxicology, the application of molecular biology principles and technologies to preclinical safety assessment, represents a key tool for understanding mechanisms of toxicity and assessing the risks associated with specific toxicities. The application of gene expression markers to early stage preclinical safety assessment has the potential to impact pipelines in two main areas: lead optimisation and issue management. Lead optimisation focuses on deprioritising leads with significant, development-limiting toxicological liabilities while advancing those compounds with the greatest chance of successfully navigating the gauntlet of preclinical and clinical safety studies. Issue management utilises mechanistic toxicology studies to position non-development-limiting findings prior to the onset of Good Laboratory Practice studies in full development, and can help to identify and validate gene expression markers predictive of adverse events to avoid issues in second-generation projects. In this review, the authors describe the application of molecular toxicology to a standard pharmaceutical testing funnel, provide examples of the successful application of gene expression markers, and discuss the potential for future impact in several broad categories of clinically relevant toxicity.