Obesity causes sympathetic activation that promotes atherosclerosis, end-organ damage, and hypertension. Because high-fat induced weight gain in rats elevates plasma leptin at 1–3 days following onset of calorie dense diets, we hypothesized that diet-induced overfeeding will increase sympathetic activity within one week following onset of the regimen. To test this, we continuously measured sympathetic activity and blood pressure before and during the onset of diet-induced obesity using a high calorie cafeteria-style diet. Female Wistar rats, in which radiotelemeters had been implanted for continuous monitoring of lumbar sympathetic activity, mean arterial pressure, and heart rate, were randomly assigned to groups that received regular chow (control) or a cafeteria diet for a period of 15 days. This short-term cafeteria-feeding regimen caused modest but non-significant increases in body weight (P = 0.07) and a doubling of brown and white adipose tissue (P < 0.01). The increases in fat mass were accompanied by elevations in plasma leptin (P < 0.001) but no change in glucose. Overall heart rates and blood pressure were higher in cafeteria rats compared with controls (P < 0.05). Cafeteria diet-induced weight gain caused increases in lumbar sympathetic nerve activity that became significant by the 12th day of the diet (p < 0.001). These data show, for the first time, that the high-fat cafeteria-style diet stimulates sustained increases in lumbar sympathetic neural drive in rats.

Highlights Retrospective multi-center study of patients with confirmed coronavirus (SARS-CoV-2). Consecutive patients requiring mechanical ventilation from March 10 to April 15, 2020 enrolled. Increased age, hypertension, statin use, increased fluid administration were associated with increased mortality. Need for continuous renal replacement therapy (CRRT), and vasopressor use were associated with increased mortality. Decreased risk of mortality in patients treated with steroids & vitamin C, & in patients with greater urine output.

Unrealistic optimism is often assessed using a single question asking for an estimate of comparative risk. However, it has been proposed that individuals treat such a question essentially as though it were only about their own risk. This proposal leads to the prediction that, when the questions about own risk and comparative risk are asked in sequence, the correlation between the resulting estimates should be lower if the question about own risk comes first than if the question about comparative risk comes first. This prediction was tested using a student sample (N=68). Participants answered the two types of question in sequence, with order of presentation being counterbalanced. Results were in accord with the prediction. Possible reasons are advanced for individuals' answering questions about comparative risk as if the questions concerned their own risk.