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Background. Obesity is related to coronary artery disease (CAD) and worse outcomes in coronary artery bypass graft (CABG) patients. Adipose tissue itself is an endocrine organ that secretes many humoral mediators, such as adipokines, which can induce or reduce inflammation and oxidative stress. Objectives. We investigate the relationship between the body mass index (BMI), inflammation, and oxidative stress by measuring serum levels of leptin, interleukin-6, and 3-nitrotyrosine in CABG patients and correlate their levels to the cardiovascular and operative risk profiles. Methods and Results. 45 men (2, who were diagnosed with CAD and scheduled for elective CABG, were included after applying the following exclusion criteria: prior myocardial infarction, reoperation, female gender, and smoking. Patients’ blood samples were taken preoperatively. Several markers were measured. We found significant correlations between leptin and BMI p<0.0001 as well as between leptin and 3-nitrotyrosine p=0.006. Interleukin-6 was correlated with C-reactive protein p<0.0001 and with the incidence of insulin-dependent diabetes mellitus p=0.036, arterial hypertension p=0.044, reduced left ventricular function p=0.003, and severe coronary calcification p=0.015. It was also associated with significantly longer extracorporeal bypass time p=0.009. Postoperative deep sternal wound infections could be predicted by a higher BMI p=0.003 and leptin level p=0.001. Conclusions. There seems to be a correlation between inflammatory processes and cardiovascular morbidity in our cohort. Further, the incidence of deep sternal wound infections is related to a higher BMI and leptin serum level.

The Ram cichlid Mikrogeophagus ramirezi (Myers & Harry, 1948) was used to examine whether flash photography can be a stressor for fish in aquaria. The point in time of the highest cortisol concentration in whole‐body homogenates was determined by the temporal course of the cortisol response following air exposure as stressor. Thus, the potential stress response to camera flashlight was examined 22 min after exposure to a single flash and after repeated flashes by applying 10 flashes per minute for 8 hr/day over 2 weeks. In both experiments the stress parameters cortisol and glucose were not increased due to exposure to the flash light. In contrast, after a single flash mean cortisol values tended to be lower and mean glucose values were significantly lower than in the control group, and after repeated flashes mean cortisol and glucose values were significantly lower than in the control group. Furthermore, treated fish showed less intraspecific aggressive interactions. These results can be explained by a possible dazzling or irritation of the fish by camera flashes, thus reducing the natural aggressive behaviour and, consequently, the concentration of stress hormones and mobilisation of glucose. In summary, the physiological stress parameters cortisol and glucose do not reveal that flash photography induces stress in M. ramirezi, and, on the contrary, might even reduce stress effects by lowering intraspecific aggressive behaviour of the fish.

Purpose. Ivabradine has emerged as a new antiarrhythmic agent that could compete with the traditional ones, such as beta-blockers. This experimental study aims to ascertain whether ivabradine directly interferes with the myocardial contractility in an in vitro environment. Methods. Myocardial tissues from the right atrial appendages of patients undergoing cardiac surgery were dissected to obtain 40 specimens from 20 patients (length: 3 mm), which were exposed to electrical impulses at a frequency of 75 bpm for 30 min to reach a steady state. Specimens were then categorised into four groups (each including five patients). The first group was the control, whereas the second, third, and fourth were treated with 60 nM, 200 nM, and 2 μM ivabradine, respectively. We assessed five different contraction parameters before and after a 15 min treatment and calculated their relative changes, which were then compared to the control group. Results. Ivabradine has affected the force of contraction significantly in vitro (p=0.009). However, force of contraction decreased in both the control group (93.5 ± 4.7%) and the second group (94.1 ± 4.5%, p=0.8) and force of contraction remained unchanged in the third group (101.0 ± 4.1%, p=0.24) and increased significantly in the fourth group (108.9 ± 11.6%, p=0.008). There was no change in other contraction parameters, such as passive tension force (97.1 ± 5.1%, p=0.368), duration of contraction (99.1 ± 4.3%, p=0.816), time to peak (96.6 ± 3.0%, p=0.536), and time to relaxation (101.2 ± 7.0%, p=0.564). Conclusions. Ivabradine did not interfere with the contractile behaviour of human atrial tissue when it was used in therapeutic dosages in vitro. However, it increased the contractility slightly, when it was used in supratherapeutic dosage.