Apelin has inhibitory effect of endothelium-independent relaxation in the human internal mammary artery

Aim: Apelin has important effects on the circulatory system and heart. The main aim of this study was to investigate the effects of apelin-13 on the contraction induced by norepinephrine (NE), and the endothelium-independent relaxation induced by sodium nitroprusside (SNP) in human internal mammary artery (IMA) obtained from patients undergoing coronary artery bypass grafting (CABG) surgery. Material and Methods: IMA rings, obtained from patients undergoing CABG surgery, were suspended in isolated tissue baths containing Krebs-Henseleit solution, which were continuously gassed with 95% O2 and 5% CO2 at 37°C. Results: The IMA rings were pre-contracted with increasing concentrations of norepinephrine (NE 10-9–10-4 mol/l) and the endothelium-independent relaxation responses to sodium nitroprusside (SNP) were studied. Apelin-13 (10 μM) caused a dosedependent relaxation in NE pre-contracted IMA rings. Apelin also facilitated the endothelium-independent relaxation induced by SNP. Conclusion: According to the results, apelin facilitated the endothelium-independent relaxation and inhibited the contractile activity of IMA. These results suggest that apelin may be a physiological agent against the deterioration of vascular elasticity caused by endothelial damage especially in atherosclerotic cardiac patients and hypertensive patients

Fuzzy Rock Mass Rating: Soft-Computing-Aided Preliminary Stability Analysis of Weak Rock Slopes

Rock mass classification systems are the most commonly used empirical tools in preliminary design of rock slopes. In spite of numerous advantages, these systems lack the common drawbacks of classification systems originated from uncertainties. These drawbacks may lead to similar or so close quality scores for different rock mass properties. Fuzzy Sets is a rising trend in describing Geomechanical problems by including the expert opinion. Especially in the case of weak rocks it allows prediction of more realistic rock mass quality scores. Although the empirical systems form a basis for the preliminary slope stability investigation, slope height and overall slope angle are still two missing important characteristic slope parameters. However, there have been some attempts to describe the graphical presentation of rock quality score, slope height and overall slope angle relation. These charts are called as slope performance charts. This chapter presents a short review on integration of Fuzzy RMR with these charts to provide a useful modification for the case of weak rock slopes

Retrospective evaluation of percutaneous tracheostomy methods applied in a tertiary intensive care unit

© 2021, Yuzuncu Yil Universitesi Tip Fakultesi. All rights reserved.Tracheostomy is a usual procedure for patients who will be dependent on ventilator therapy for a long time to reduce complications associated with long-term endotracheal intubation. Different percutaneous methods focused on safety and convenience have also been described to perform tracheostomy. There are still some debates which technique is the most easy to applicate and safe. In this study, it was aimed to evaluate the Griggs’ guide wire dilatational and Ciaglia’s blue rhino techniques in terms of safety and convenience. After obtaining ethical approval from local ethical committee, file records of patients stayed in our ICU between March 2019 and March 2020 were assessed. Fifty four patients to whom percutaneous tracheostomy applied were included in the study Among the patients included in the study, the groups were similar according to the age, gender and duration of intubation. The procedure time was less in the Group GWFD (mean±SD; 18.62±6.92 mins) than in Group BR (mean±SD; 23.40±5.37 mins) (p: 0.006). There was no difference between the groups in terms of minor bleeding, major bleeding, pneumothorax, emphysema and hypoxia. But the total complication rate was higher in Group GWFD [10 (41.7%)] than in Group BR [5 (16.7%)] (p: 0.042). This study’s results reveal that the GWFD technique is faster but the BR technique is safer. Differences in the definition of procedure time may have affected the results. For this reason, more studies are needed in this area