This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
[{'content': 'Gall blader stone formation in influenced by AJE - \nSelect and explain. \nA. Clofibrate therapy, B. Hyperalimentation, C. Primary biliary cirrhosis, D. Hypercholesterolemia', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Hyper alimentation - decreases gall bladder motility, promotes stasis\nPrimary biliary cirrhosis - decreases bile salt secretion into bile\nClofibrate therapy - increases biliary cholesterol\nthus these factors predispose to cholesterol stone formation.\n\nPredisposing factors for cholesterol gall stone formation are\n1. Demographic/genetic factors\n\nPrevalence highest in North American Indians, Chilean Indians and Chilean Hispanics, greater in Northern Europe and North America than in Asia, lowest in Japan; familial disposition; hereditary aspects.\n\n2. Obesity\n\nNormal bile acid pool and secretion but increased biliary secretion of cholesterol\n\n3.\xa0\xa0\xa0 Weight loss\n\nMobilization of tissue cholesterol leads to increased biliary cholesterol secretion while enterohepatic circulation of bile acid is increased\n\n4. Female sex hormones\n\nEstrogens stimulate hepatic lipoprotein receptors, increases uptake of dietary cholesterol, and increase biliary cholesterol secretion\nNatural estrogens, other estrogens, and oral contraceptives lead to decreased bile salt secretion and decreased conversion of cholesterol to cholesteryl esters.\n\n5. Increasing age\n\nIncreased biliary secretion of cholesterol, decreased size of bile acid pool, decreased secretion of bile salts.\n\n6.\xa0Gallbladder hypomotility leading to stasis and formation of sludge\n\nProlonged parenteral nutrition\nFasting\nPregnancy\nDrugs such as octreotide\n\n7. Clofibrate therapy\n\nIncreased biliary secretion of cholesterol\n\n8.\xa0\xa0\xa0 Decreased bile acid secretion\n\nPrimary biliary cirrhosis\nGenetic defect of the CYP7A1 gene\n\n9.\xa0\xa0\xa0 Decreased phospholipid secretion\n\nGenetic defect of the MDR3 gene\n\n10. Miscellaneous\n\nHigh-calorie, high fat diet\nSpinal cord injury', 'role': 'assistant'}]