This study was conducted to determine whether there is a reliable method for measuring the thickness of the retroauricular skin before, during, and after cochlear implantation, which allows the ...assessment of the optimal force of the external magnet of the cochlear implant (CI).
The retroauricular skin thickness of 83 patients who received a CI was measured using three different methods. The thickness was measured on pre- and postoperative CT images, as well as intraoperatively. The magnet category chosen by the surgeon was recorded when the implant was switched on and during the first follow-up visit. Correlation analyses were performed on the different skin thickness measurements and between the skin thickness and magnet strength categories.
Only six patients required an exchange of the magnet until the follow-up. Although the median absolute thickness differed significantly between the three measures (p < 0.0001), their thickness values showed highly significant correlations (Pearson's r = 0.457–0.585; p < 0.01). In addition, magnet strength, was significantly correlated with the flap thickness determined pre-, post-, and during surgery. The lowest correlation with magnet strength was found in the intraoperative needle method.
All three measurements methods provided a suitable base for determining the ideal magnetic force. However, of particular interest were the pre- and postoperative CT measurements. The first enabled the early assessment of the required magnetic strength and thus a timely postoperative supply, whereas the latter helped to estimate the need for magnetic strength reduction during follow-up care and the feasibility of an early swith-on.
Due to the limited compliance, the technically correct collection of a pooled nasopharyngeal swab is significantly more difficult in children. Especially during operations in the area of the upper ...respiratory tract, there is a significantly increased risk of infection with COVID-19 for everyone present in the operating room. The aim of the study is to analyze the validity of SARS-CoV-2 swabs taken preoperatively under suboptimal conditions.
Retrospective comparison of the PCR results of SARS-CoV-2 swaps taken preoperatively and intraoperatively from 62 children in the period from April to July 2020. Median age was 4.49 years. The PCR diagnosis was carried out one or two days preoperatively (in the case of emergency interventions on the same day) and again intraoperatively using a pooled nasopharyngeal swab.
All 62 preoperatively taken swabs were negative. Deviating from the preoperative test result, one intraoperatively obtained swab was positive.
Due to limited compliance, a correct preoperative swab technique (preanalytics) cannot always be assumed for children. Sufficient protective measures for everyone present in the operating room are therefore imperative. Intraoperative test should be considered if the preoperative test was performed under difficult conditions.
Abdominal pain is a frequent symptom in patients with inflammatory bowel disease (IBD) including Crohn's disease (CD) and ulcerative colitis (UC). Pain can result from ongoing inflammation or ...functional disorders imitating irritable bowel syndrome (IBS). Several single-nucleotide polymorphisms (SNPs) have been associated with IBS. However, the impact of IBS genetics on the clinical course of IBD, especially pain levels of patients remains unclear.
Data of 857 UC and 1206 CD patients from the Swiss IBD Cohort Study were analysed. We tested the association of the maximum of the abdominal pain item of disease activity indices in UC and CD over the study period with 16 IBS-associated SNPs, using multivariate ANOVA models.
In UC patients, the SNPs rs1042713 (located on the ADRB2 gene) and rs4663866 (close to the HES6 gene) were associated with higher abdominal pain levels (P = 0.044; P = 0.037, respectively). Abdominal pain was not associated with any markers of patient management in a model adjusted for confounders. In CD patients, higher levels of abdominal pain correlated with the number of physician contacts (P < 10
), examinations (P < 10
), medical therapies (P = 0.023) and weeks of hospitalisation (P = 0.0013) in a multivariate model.
We detected an association between maximal abdominal pain in UC patients and two IBS-associated SNPs. Abdominal pain levels had a pronounced impact on diagnostic and therapeutic procedures in CD but not in UC patients.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The pK values of the titratable groups in ribonuclease Sa (RNase Sa) (pI=3.5), and a charge-reversed variant with five carboxyl to lysine substitutions, 5K RNase Sa (pI=10.2), have been determined by ...NMR at 20 degrees C in 0.1M NaCl. In RNase Sa, 18 pK values and in 5K, 11 pK values were measured. The carboxyl group of Asp33, which is buried and forms three intramolecular hydrogen bonds in RNase Sa, has the lowest pK (2.4), whereas Asp79, which is also buried but does not form hydrogen bonds, has the most elevated pK (7.4). These results highlight the importance of desolvation and charge-dipole interactions in perturbing pK values of buried groups. Alkaline titration revealed that the terminal amine of RNase Sa and all eight tyrosine residues have significantly increased pK values relative to model compounds.A primary objective in this study was to investigate the influence of charge-charge interactions on the pK values by comparing results from RNase Sa with those from the 5K variant. The solution structures of the two proteins are very similar as revealed by NMR and other spectroscopic data, with only small changes at the N terminus and in the alpha-helix. Consequently, the ionizable groups will have similar environments in the two variants and desolvation and charge-dipole interactions will have comparable effects on the pK values of both. Their pK differences, therefore, are expected to be chiefly due to the different charge-charge interactions. As anticipated from its higher net charge, all measured pK values in 5K RNase are lowered relative to wild-type RNase Sa, with the largest decrease being 2.2 pH units for Glu14. The pK differences (pK(Sa)-pK(5K)) calculated using a simple model based on Coulomb's Law and a dielectric constant of 45 agree well with the experimental values. This demonstrates that the pK differences between wild-type and 5K RNase Sa are mainly due to changes in the electrostatic interactions between the ionizable groups. pK values calculated using Coulomb's Law also showed a good correlation (R=0.83) with experimental values. The more complex model based on a finite-difference solution to the Poisson-Boltzmann equation, which considers desolvation and charge-dipole interactions in addition to charge-charge interactions, was also used to calculate pK values. Surprisingly, these values are more poorly correlated (R=0.65) with the values from experiment. Taken together, the results are evidence that charge-charge interactions are the chief perturbant of the pK values of ionizable groups on the protein surface, which is where the majority of the ionizable groups are positioned in proteins.
In this paper, the authors call for an approach that, in recognizing the economic realities facing most institutions, attempts to put aside objections that funding is simply not available to support ...an expansion of the current tenure system. In calling for the changes in faculty working conditions, the authors recognize that change will necessarily occur in local contexts, but they also recognize the role that National Council of Teachers of English (NCTE), its affiliate organizations and assemblies, and its members can play in supporting change at the local institutional level. Their argument rests on two observations. First, they believe it is necessary to change the relationship between instructors who are currently employed in contingent positions and the institutions which employ them. Second, they believe it is necessary to fully involve faculty members who do not have tenure-line appointments in the programs that employ them. They offer position statement on the status and working conditions of faculty members serving in contingent positions in the hope that they can build on previous statements, while shifting the argument from expanding the current tenure system to creating a structure that provides long-term security of employment for faculty who are not hired into traditional tenure lines. This policy statement from a committee of the NCTE College Section identifies problems with the discipline's dependence on contingent faculty and makes recommendations for better treatment of them. (Contains 2 notes.)
The primary goal of this study was to gain a better understanding of the effect of environment and ionic strength on the pK values of histidine residues in proteins. The salt-dependence of pK values ...for two histidine residues in ribonuclease Sa (RNase Sa) (pI=3.5) and a variant in which five acidic amino acids have been changed to lysine (5K) (pI=10.2) was measured and compared to pK values of model histidine-containing peptides. The pK of His53 is elevated by two pH units (pK=8.61) in RNase Sa and by nearly one pH unit (pK=7.39) in 5K at low salt relative to the pK of histidine in the model peptides (pK=6.6). The pK for His53 remains elevated in 1.5M NaCl (pK=7.89). The elevated pK for His53 is a result of screenable electrostatic interactions, particularly with Glu74, and a non-screenable hydrogen bond interaction with water. The pK of His85 in RNase Sa and 5K is slightly below the model pK at low salt and merges with this value at 1.5M NaCl. The pK of His85 reflects mainly effects of long-range Coulombic interactions that are screenable by salt. The tautomeric states of the neutral histidine residues are changed by charge reversal. The histidine pK values in RNase Sa are always higher than the pK values in the 5K variant. These results emphasize that the net charge of the protein influences the pK values of the histidine residues. Structure-based pK calculations capture the salt-dependence relatively well but are unable to predict absolute histidine pK values.
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