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Lee and Chandraratna provide evidence of dry gangrene in the right foot of a 62-year-old man and evidence of a mobile arch atheroma. They suggest that thromboembolism from atheroma is an important cause of stroke and peripheral embolism. We agree. However, we would suggest that this is not a case of "thromboembolism," as it is characterized in the second paragraph. The presence of both the dorsalis pedis and posterior tibial pulses in the affected foot suggests that there has not been a fibroplatelet embolic event. Indeed, this constellation is more suggestive of cholesterol crystal embolization -how else to explain the preserved pulses? Also, single-vessel infrapopliteal occlusion typically does not cause intermittent claudication, much less gangrene. We suggest that the transesophageal echocardiogram reveals a ruptured plaque and substrate for cholesterol emboli, not thromboembolism. Burke AP, FarbA, Malcom GT, Liang YH, Smialek J, Virmani R. Coronary risk factors and plaque morphology in men with coronary disease who died suddenly. N Engl J Med 1997;336:1276-82. 2. Kolodgie FD, Narula J, Burke AP, et al. Localization of apoptotic macrophages at the site of plaque rupture in sudden coronary death. Am J Pathol 2000;157:1259-68. 3. Kolodgie FD, Petrov A, Virmani R, et al. Targeting of apoptotic macrophages and experimental atheroma with radiolabeled annexin-V: a technique with potential for noninvasive imaging of vulnerable plaque. Circulation 2003;108:3134-9. 4. Hofstra L, Liem IH, Dumont EA, et al. Visualisation of cell death in vivo in patients with acute myocardial infarction.

In this study, we investigated the hypothesis that impairments in forearm skeletal muscle free fatty acid (FFA) metabolism are present in patients with type 2 diabetes both in the overnight fasted state and during beta-adrenergic stimulation. Eight obese subjects with type 2 diabetes and eight nonobese controls (Con) were studied using the forearm balance technique and indirect calorimetry during infusion of the stable isotope tracer [U-(13)C]palmitate after an overnight fast and during infusion of the nonselective beta-agonist isoprenaline (Iso, 20 ng. kg lean body mass(-1) x min(-1)). Additionally, activities of mitochondrial enzymes and of cytoplasmatic fatty acid-binding protein (FABP) were determined in biopsies from the vastus lateralis muscle. Both during fasting and Iso infusion, the tracer balance data showed that forearm muscle FFA uptake (Con vs. type 2: fast 449+/-69 vs. 258 +/-42 and Iso 715+/-129 vs. 398+/-70 nmol. 100 ml tissue(-1) x min(-1), P<0.05) and FFA release were lower in type 2 diabetes compared with Con. Also, the oxidation of plasma FFA by skeletal muscle was blunted during Iso infusion in type 2 diabetes (Con vs. type 2: Iso 446 +/- 274 vs. 16+/-70 nmol. 100 ml tissue(-1) x min(-1), P<0.05). The net forearm glycerol release was increased in type 2 diabetic subjects (P< 0.05), which points to an increased forearm lipolysis. Additionally, skeletal muscle cytoplasmatic FABP content and the activity of muscle oxidative enzymes were lowered in type 2 diabetes. We conclude that the uptake and oxidation of plasma FFA are impaired in the forearm muscles of type 2 diabetic subjects in the overnight fasted state with and without Iso stimulation.

(1994). Beta-adrenergic stimulation of energy expenditure and forearm skeletal muscle metabolism in lean and obese men. American Journal of Physiology, 267(2), E306-E315.

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