Surgical fear questionnaire (SFQ) - Serbian cultural adaptation

© 2020 Inst. Sci. inf., Univ. Defence in Belgrade. All rights reserved. Background/Aim. After having established an indication for surgery, some patients experience sense of fear, unpleasantness and embarrassment due to the expectance of adverse consequences of surgical intervention. Recently an instrument for measuring fear of surgery - the Surgical Fear Questionnaire (SFQ) - was developed and validated on a sample of Dutch patients awaiting surgery. The objective of this study was to translate the SFQ to Serbian language, make cultural adaptation of the translation and test its reliability and validity in a sample of outpatients in Serbia. Methods. The SFQ was translated and adapted according to the accepted international standards (double forward translation, harmonization, backward translation, and piloting). The study was multicentric, involving patients from 7 cities in 3 countries: Serbia, Montenegro, Bosnia and Hercegovina. It was conducted at state-owned health facilities. The sample was of consecutive nature and consisted of 330 outpatients who visited specialists of either internal medicine or general surgery. Results. Translated SFQ showed excellent reliability, both when rated by the investigators (Cronbach's alpha 0.915), and by the patients themselves (Cronbach's alpha 0.917). It is temporally stable, and both divergent and convergent validity tests had good results. Factorial analysis revealed one domain on the whole study sample and two domains like in original on the subsample of patients without experience with surgery in general anesthesia. Conclusion. Identification of patients with high level of fear of surgery by this questionnaire should help clinicians to administer measures which may decrease fear and prevent avoidance of absolutely necessary surgery by such patients

Paramagnetic relaxation enhancement of membrane proteins by incorporation of the metal-chelating unnatural amino acid 2-amino-3-(8-hydroxyquinolin-3-yl)propanoic acid (HQA)

The use of paramagnetic constraints in protein NMR is an active area of research because of the benefits of long-range distance measurements (>10 Å). One of the main issues in successful execution is the incorporation of a paramagnetic metal ion into diamagnetic proteins. The most common metal ion tags are relatively long aliphatic chains attached to the side chain of a selected cysteine residue with a chelating group at the end where it can undergo substantial internal motions, decreasing the accuracy of the method. An attractive alternative approach is to incorporate an unnatural amino acid (UAA) that binds metal ions at a specific site on the protein using the methods of molecular biology. Here we describe the successful incorporation of the unnatural amino acid 2-amino-3-(8-hydroxyquinolin-3-yl) propanoic acid (HQA) into two different membrane proteins by heterologous expression in E. coli. Fluorescence and NMR experiments demonstrate complete replacement of the natural amino acid with HQA and stable metal chelation by the mutated proteins. Evidence of site-specific intra- and inter-molecular PREs by NMR in micelle solutions sets the stage for the use of HQA incorporation in solid-state NMR structure determinations of membrane proteins in phospholipid bilayers