Chapter 29: Hyperlipidemia
Lipoproteins contain which of the following?
B. Nonesterified cholesterol
The answer is E. (Hurst’s The Heart, 14th Edition, Chap. 29) The basic structure of all lipoproteins is similar. They contain a core of neutral lipid (triglyceride and cholesterol ester) (option A) that is surrounded by a polar coat containing nonesterified cholesterol (option B), phospholipid (option C), and proteins (called apolipoproteins) (option D). The major categories of lipoproteins consist of low-density lipoprotein (LDL), very-low-density lipoprotein (VLDL), high-density lipoprotein (HDL), and chylomicrons. These lipoproteins vary in size and density. Because lipoproteins can be separated by electrophoresis, they also have been named according to their migration relative to serum proteins. LDL is called beta lipoprotein, VLDL is pre-beta lipoprotein, and HDL is alpha lipoprotein.
A 40-year-old man with a history of hyperlipidemia has an inferior MI. Multiple members of his family have had coronary events in their early 40s. Which of the following types of studies do not provide evidence to support the idea that an elevated plasma LDL is a major risk factor for atherosclerotic cardiovascular disease (ASCVD)?
B. Genetic forms of elevated LDL
C. Epidemiological associations
D. Randomized controlled trials
E. All of the above support the idea
The answer is E. (Hurst’s The Heart, 14th Edition, Chap. 29) An elevated plasma LDL is designated a major risk factor for ASCVD. Several lines of evidence support a strong association: animal studies (option A), genetic forms of elevated LDL (option B), epidemiological associations (option C), and randomized controlled trials (RCTs) of LDL-lowering therapies (option D).
Which of the following steps in the progression of atherosclerosis is incorrect?
A. Accumulation of large numbers of foam cells gives rise to fatty streaks
B. Some foam cells die and release their cholesterol esters into the interstitium, and over time the core of extracellular lipid expands
C. Osteoclasts from the medium begin to produce fibrous connective tissue
D. This tissue forms a covering of the fatty streak; here the lesion is called a fibrous plaque (fibroatheroma)
E. Continuous filtration of LDL into the arterial wall leads to ...