596 adjustment for number of cigarettes changes the OR to 1 61 (071-366), a 2% decrease. Among current smokers, the respective ORs are 1 67 (1 12-2-49), 2 02 (1 23-3-32), and 1-66 (1 00-2 80) (18% decrease). These results indicate that some of the increased risk at low &bgr;-carotene was still due to smoking, but an independent association of &bgr;-carotene and MI remains. Alwine F M Kardinaal, Pieter van ’t Veer, Frans J Kok, for the EURAMIC Study Group Epidemiology Section, TNO Nutrition and Food Research, 3700 AJ Zeist, Netherlands; and Department of Epidemiology and Public Health, Agricultural University, Wageningen 1 Cohen MV. Free radicals in ischemic and reperfusion myocardial injury: is this the time for clinical trials? Ann Intern Med 1989; 111: 918-31. 2 Keil U, Kuulasma K. WHO MONICA Project: risk factors. Int J Epidemiol 1989; 18: S46-S55. 3 Gey FK, Puska P, Jordan P, Moser UK. Inverse correlation between plasma vitamin E and mortality from ischemic heart disease in cross-cultural epidemiology. Am J Clin Nutr 1991; 53: 326-34. SIR&mdash;Kardinaal et al show that &bgr;-carotene in adipose tissue is inversely correlated with risk of coronary heart disease (CHD), and vitamin E is effective only in supplement users. The authors hypothesise that such an effect may be linked to reduced oxidation of low-density lipoprotein (LDL). There could be another explanation. It is widely known that hyperinsulinaemia/insulin resistance is associated with many cardiovascular risk factors1-2 and may play a part in the genesis of CHD. On the other hand, vitamin E administration has been shown to improve the action of insulin in healthy subjects and non-insulin-dependent diabetic patients.4 It is therefore possible that the protective effect of antioxidant agents might be linked to the effect of such vitamins on insulin action. We investigated the effect of pharmacological doses of vitamin E (900 mg daily of dl fx-tocopherol acetate, Roche, Italy) on insulin action in 26 elderly (mean [SEM] 73-1 [3&deg;1] years) patients with CHD. The study design was double-blind, randomised, and cross-over versus placebo. Each treatment period lasted 4 months and was separated by a 2 month wash-out. All patients continued their cardiovascular treatment throughout and all ate a diet containing 250 g or more carbohydrate per day. No diabetic patients were enrolled for the study. At the end of each treatment period patients had a euglycaemic hyperinsulinaemic (1-2 mU/kg per min for 120 min) glucose clamp. Vitamin E administration was associated with a significant decline in fasting plasma insulin (88 [ 13] vs 67 [10] pmol/L, p<0-05), whereas fasting plasma glucose (5-7 [0’4] vs 5-8 [0-6] mmol/L) was similar in both groups, and M value (44 [0-3] vs 5-8 [0-8] mg/kg per min, p<0’03) was significantly improved. Furthermore, a significant correlation (r=0-49, p<0’02, n=26) between net changes (difference between placebo and vitamin E administration) in plasma vitamin E and M value was found. Such an effect of vitamin E on insulin action might be explained through improvement in membrane microviscosity and glucose transport.4,5 Despite the small number of patients, our data seem to strengthen Kaardinal and colleagues’ results and suggest that vitamin E administration may usefully improve insulin action in patients with CHD. Giuseppe Paolisso Clinical Diabetes and Nutrition Section, 4212 North 16th Street, Phoenix, AZ 85016 USA Antonio Gambardella, Domenico Galzerano, Michele Varricchio, Felice D’Onofrio Department of Geriatric Medicine and Metabolic Diseases, II University of Naples, Naples, Italy 1 De Fronzo RA, Ferrannini E. Insulin resistance. A multifaced syndrome responsible for NIDDM, obesity hypertension dyslipidemia and atherosclerotic cardiovascular disease. Diabetes Care 1991; 14: 173-94. 2 Reaven GM. Insulin resistance and compensatory hyperinsulinemia. Role in hypertension, dyslipidemia and coronary heart disease. Am Heart J 1991; 121: 1283-88. 3 Fontbonne A, Charles MA, Thibult N, Richard JL, Claude JR, Warnet JM. Hyperinsulinemia as a predictor for coronary heart disease in a healthy population: the Paris Prospective Study, 15 years follow up. Diabetologia 1991; 34: 356-61. 4 Paolisso G, D’Amore A, Giugliano D, Ceriello A, Varricchio M, D’Onofrio F. Pharmacological doses of vitamin E improve insulin action in healthy subjects and non-insulin dependent diabetic patients. Am J Clin Nutr 1993; 57: 650-56. 5 Whiteshell RB, Rijen DM, Beth AH, Pelletier DK, Abumrod NA. Activation energy of slowest step in the glucose carrier cycle: correlation with membrane lipid fluidity. Biochemistry 1989; 28: 5618-25. Robotic Interactive laparoscopic cholecystectomy SIR&mdash;Whereas most applications of robotics in medicine focus on education,’ rehabilitation and clinical interfacing,3 many laboratories are experimenting with their use in surgery.4,5 Further to laboratory and animal experimentation, the ethics committee of Hotel Dieu de Montreal Hospital approved a pilot study on the clinical application and feasibility of robotic interactive laparoscopic cholecystetomy in human beings. A robotic arm (A460 CRS Plus, Burlington, Ontario, Canada) with 6 degrees of freedom was modified with interfaces to accept a mini-camera that interlocked with the ocular piece (Stryker) of a 10 mm laparoscope. Movements of the robotic arm were controlled with a remote joystick under video image in a separate room. Because the laparoscope was maintained in the umbilical trocar, a rigid tunnel through the abdominal wall provided a central axis of motion, and various motions (left-right, up-down, in-out, and rotation) of the camera outside the abdomen presented different image fields in the abdominal cavity. The control box equipped with the joystick and two potentiometers provided teleoperated left- right and up-down movements and two push buttons facilitated in-out and rotational movements. An ideal video image was maintained (localising and centering the tips of the laparoscopic instruments) by moving the joystick and push buttons while looking at a separate video screen. Electronic and mechanical devices were installed to assure maximum security. The characteristics of this technology included a 3 kg payload, 0 85 m reach, 4-62 m/s maximum speed, and 0-005 repeatability. On Sept 1, 1993, three patients (33/M, 45/F, 53/F) with symptomatic gallstones had laparoscopic cholecystectomy with robotic assistance. After obtaining their informed signed consent, carbon dioxide insufflation and insertion of an umbilical 11 mm trocar were done under general anaesthesia. The robotic arm located on the left side of the patient (lower half) was connected to the laparoscope in the umbilical trocar. 3-dimensional movements (20 cm3) of the laparoscope were continuously conducted with the robotic arm to provide optimum vision to the operating surgeon. An 11 mm trocar was installed in the epigastric region and two 5 mm trocars in the right subcostal area. Laparoscopic cholecystectomy and intraoperative cholangiograms followed. The gallbladder was expelled through the epigastric wound and the robotic arm was disconnected. There were no intraoperative complications or technical problems. Operating time was 50, 30, and 30 min, respectively, and blood loss was negligible. The postoperative period was similar to that of previous laparoscopic cholecystectomy patients, with negligible abdominal pain and hospital stays of less than 24 h in two patients and less than 48 h in the third