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Membrane lipids extensively modulate the activation gating of voltage-gated potassium channels (KV), however, much less is known about the mechanisms of ceramide and glucosylceramide actions including which structural element is the main intramolecular target and whether there is any contribution of indirect, membrane biophysics-related mechanisms to their actions. We used two-electrode voltage-clamp fluorometry capable of recording currents and fluorescence signals to simultaneously monitor movements of the pore domain (PD) and the voltage sensor domain (VSD) of the KV1.3 ion channel after attaching an MTS-TAMRA fluorophore to a cysteine introduced into the extracellular S3-S4 loop of the VSD. We observed rightward shifts in the conductance-voltage (G-V) relationship, slower current activation kinetics, and reduced current amplitudes in response to loading the membrane with C16-ceramide (Cer) or C16-glucosylceramide (GlcCer). When analyzing VSD movements, only Cer induced a rightward shift in the fluorescence signal-voltage (F-V) relationship and slowed fluorescence activation kinetics, whereas GlcCer exerted no such effects. These results point at a distinctive mechanism of action with Cer primarily targeting the VSD, while GlcCer only the PD of KV1.3. Using environment-sensitive probes and fluorescence-based approaches, we show that Cer and GlcCer similarly increase molecular order in the inner, hydrophobic regions of bilayers, however, Cer induces a robust molecular reorganization at the membrane-water interface. We propose that this unique ordering effect in the outermost membrane layer in which the main VSD rearrangement involving an outward sliding of the top of S4 occurs can explain the VSD targeting mechanism of Cer, which is unavailable for GlcCer.

The conformational properties of Alanine (Ala) residue have been investigated to understand protein folding and develop force fields. In this work, we examined the neighbor effect on the conformational spaces of Ala residue using model azapeptides, Ac-Ala-azaGly-NHMe (3, AaG), and Ac-azaGly-Ala-NHMe (4, aGA1). Ramachandran energy maps were generated by scanning (φ, ψ) dihedral angles of the Ala residues in models with the fixed dihedral angles (φ = ±90°, ψ = ±0° or ±180°) of azaGly residue using LCgau-BOP and LCgau-BOP + LRD functionals in the gas and water phases. The integral-equation-formalism polarizable continuum model (IEF-PCM) and a solvation model density (SMD) were employed to mimic the solvation effect. The most favorable conformation of Ala residue in azapeptide models is found as the polyproline II (βP), inverse γ-turn (γ′), β-sheet (βS), right-handed helix (αR), or left-handed helix (αL) depending on the conformation of neighbor azaGly residue in isolated form. Solvation methods exhibit that the Ala residue favors the βP, δR, and αR conformations regardless of its position in azapeptides 3 and 4 in water. Azapeptide 5, Ac-azaGly-Ala-NH2 (aGA2), was synthesized to evaluate the theoretical results. The X-ray structure showed that azaGly residue adopts the polyproline II (βP) and Ala residue adopts the right-handed helical (αR) structure in aGA2. The conformational preferences of aGA2 and the dimer structure of aGA2 based on the X-ray structure were examined to assess the performance of DFT functionals. In addition, the local minima of azapeptide 6, Ac-Phe-azaGly-NH2 (FaG), were compared with the previous experimental results. SMD/LCgau-BOP + LRD methods agreed well with the reported experimental results. The results suggest the importance of weak dispersion interactions, neighbor effect, and solvent influence in the conformational preferences of Ala residue in model azapeptides.

Synthesis and characterization of the optical properties of materials especially at a nanoscale, is considered as important tasks for the engineering of photonic devices and systems. In this paper we study the photoluminescence of new nanocomposite material consisting of arsenic sulfide doped in porous glasses and the effect of photoinduced structural transformations on it. The nanocomposite was obtained via chemical deposition method in which arsenic sulfide powder was dissolved in an amine solution and then clean pieces of porous glass were impregnated for 2 days in the solution. Strong photoluminescence signal was observed in the samples when excited with lasers with excitation wavelengths of 405 and 532 nm. Also, the effect of laser irradiation on the photoluminescence of the samples was studied using confocal microscope with two different operating lasers 405 and 514 nm. It was observed that laser irradiation influences photoluminescence differently depending on the irradiation wavelength.

People in economically advantaged nations tend to evaluate their life as more positive overall and report greater well-being than people in less advantaged nations. But how does positivity manifest in the daily life experiences of individuals around the world? The present study asked 15,244 college students from 62 nations, in 42 languages, to describe a situation they experienced the previous day using the Riverside Situational Q-sort (RSQ). Using expert ratings, the overall positivity of each situation was calculated for both nations and individuals. The positivity of the average situation in each nation was strongly related to the economic development of the nation as measured by the Human Development Index (HDI). For individuals’ daily experiences, the economic status of their nation also predicted the positivity of their experience, even more than their family socioeconomic status. Further analyses revealed the specific characteristics of the average situations for higher HDI nations that make their experiences more positive. Higher HDI was associated with situational experiences involving humor, socializing with others, and the potential to express emotions and fantasies. Lower HDI was associated with an increase in the presence of threats, blame, and hostility, as well as situational experiences consisting of family, religion, and money. Despite the increase in a few negative situational characteristics in lower HDI countries, the overall average experience still ranged from neutral to slightly positive, rather than negative, suggesting that greater HDI may not necessarily increase positive experiences but rather decrease negative experiences. The results illustrate how national economic status influences the lives of individuals even within a single instance of daily life, with large and powerful consequences when accumulated across individuals within each nation.

In this paper, we presented the dataset values of full width at half maximum (FWHM) with errors at each point corresponding to the value of longitudinal and transverse residual stress along the three lines for 14 points measured in the EBW welded joints (S960QL and S960M) of the related article [1]. This dataset is used to plot figures and describes their correspondence points with the interrelation of the residual stress graphs (Fig. 4) of the article [1]. The shape of the diffracted peak can be characterised in a simple way by the FWHM, which is the width in degree at half the peak height after background extraction. The measured width consist of instrumental and metallurgical broadening. The variation or increase in FWHM is resulted from the crystalline lattice defect e.g. solute foreign atoms, dislocations and grain boundary. Conversely, if we can determine the physical broadening, we get more information about the structure of the investigated material. In addition, the optical microscopic image of the base materials and weld microstructure are the other parts of the data. Diffraction data were collected using centreless X-ray diffraction (XRD) during in situ residual stress measurement of high strength structural steels S960QL and S960M. A more detailed interpretation of the data presented in this article is provided in article [1]. The presented data are produced as part of the main work entitled “Comparative evaluation of residual stresses in vacuum electron beam welded high strength steel S960QL and S960M butt joints [1]”.

Prevalence of teenage pregnancy is very high in the Central Region of Ghana. Although, pregnant teenagers are perceived to be high-risk mothers, very little has been documented about obstetric outcomes among these mothers in Ghana. This case-control observational study compared maternal and perinatal outcomes between teen and adult mothers in the Cape Coast metropolis. Data on maternal and perinatal outcome variables were collected with a data extraction form from maternal history record and delivery record books of 505 teens and 501 adults. Maternal and perinatal outcomes for the two groups were compared using chi-square or Fisher's exact test and odds ratios at 95% confidence interval. Prenatal services utilization was high among the participants. Prevalence of adverse maternal and perinatal outcomes were low, which is comparable between the two groups. Spontaneous vaginal delivery was higher in the teens with the adults having higher predisposition for caesarean section. The adult mothers were more likely to have preterm delivery and babies with low minute 1 APGAR score, the teens on the other hand had babies with significantly lower birth weight. The favourable and comparable pregnancy outcomes among the participants could be attributed to the high prenatal service utilization. Improved access to prenatal service utilization would produce better pregnancy outcomes.

Inflammatory myofibroblastic tumors (IMTs) are rare soft-tissue tumors that can occur at virtually any anatomical site. We report the case of a 58-year-old male with an IMT of the fourth part of the duodenum who presented with signs and symptoms of high intestinal obstruction and bilious vomiting. The patient underwent a surgical resection of the fourth part of the duodenum with end-to-end duodenojejunal anastomosis. The follow-up period of 6 months was uneventful with no evidence of recurrence. According to our knowledge, only six cases of duodenal IMTs have been reported in the literature thus far, and this is the first report of a duodenal IMT sited at the fourth part of the duodenum. The duodenum is among the rarest sites of IMTs. Signs and symptoms resulting from diagnostic imaging investigations are nonspecific and inadequate to obtain diagnosis accurately. In most cases, surgical treatment is considered a cure for IMTs. There is no evidence of deaths caused by duodenal IMT. IMT of the duodenum is a possible diagnosis in differential diagnosis of tumor-like lesions of the duodenum.

Introduction: High quality epidemic forecasting and prediction are critical to support response to local, regional and global infectious disease threats. Other fields of biomedical research use consensus reporting guidelines to ensure standardization and quality of research practice among researchers, and to provide a framework for end-users to interpret the validity of study results. The purpose of this study was to determine whether guidelines exist specifically for epidemic forecast and prediction publications., Methods: We undertook a formal systematic review to identify and evaluate any published infectious disease epidemic forecasting and prediction reporting guidelines. This review leveraged a team of 18 investigators from US Government and academic sectors., Results: A literature database search through May 26, 2019, identified 1467 publications (MEDLINE n = 584, EMBASE n = 883), and a grey-literature review identified a further 407 publications, yielding a total 1777 unique publications. A paired-reviewer system screened in 25 potentially eligible publications, of which two were ultimately deemed eligible. A qualitative review of these two published reporting guidelines indicated that neither were specific for epidemic forecasting and prediction, although they described reporting items which may be relevant to epidemic forecasting and prediction studies., Conclusions: This systematic review confirms that no specific guidelines have been published to standardize the reporting of epidemic forecasting and prediction studies. These findings underscore the need to develop such reporting guidelines in order to improve the transparency, quality and implementation of epidemic forecasting and prediction research in operational public health., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Searching for patient cohorts in electronic patient data often requires the definition of temporal constraints between the selection criteria. However, beyond a certain degree of temporal complexity, the non-graphical, form-based approaches implemented in current translational research platforms may be limited when modeling such constraints. In our opinion, there is a need for an easily accessible and implementable, fully graphical method for creating temporal queries. We aim to respond to this challenge with a new graphical notation. Based on Allen's time interval algebra, it allows for modeling temporal queries by arranging simple horizontal bars depicting symbolic time intervals. To make our approach applicable to complex temporal patterns, we apply two extensions: with duration intervals, we enable the inference about relative temporal distances between patient events, and with time interval modifiers, we support counting and excluding patient events, as well as constraining numeric values. We describe how to generate database queries from this notation. We provide a prototypical implementation, consisting of a temporal query modeling frontend and an experimental backend that connects to an i2b2 system. We evaluate our modeling approach on the MIMIC-III database to demonstrate that it can be used for modeling typical temporal phenotyping queries., (Copyright © 2019 Elsevier Inc. All rights reserved.)

A novel arginine-based cationic surfactant N α -benzoyl-arginine dodecylamide (Bz-Arg-NHC 12 ) was synthesized in our laboratory. In this paper we study the interaction of Bz-Arg-NHC 12 with sheep and human red blood cells (SRBC and HRBC respectively) due to their different membrane physicochemical/biophysical properties. SRBC demonstrated to be slightly more resistant than HRBC to the hemolytic effect of the surfactant, being the micellar structure responsible for the hemolytic effect in both cases. Moreover, besides the hemolytic effect, a dual behavior was observed for the surfactant studied: Bz-Arg-NHC 12 was also able to protect red blood cells against hypotonic lysis for HRBC in a wide range of surfactant concentrations. However, the degree of protection showed for SRBC was about 50% lower than for HBRC. In this regard, a remarkable volume expansion was evidenced only for SRBC treated with Bz-Arg-NHC 12 , although no correlation with the antihemolytic potency (pAH) was found. On the contrary, our surfactant showed a greater pAH when human erythrocytes were submitted to hypotonic stress, with a low volume expansion, showing a higher amount of solubilized phospholipids in the supernatant when compared with SRBC behavior. Surface plasmon resonance measurements show the molecular interaction of the surfactant with lipid bilayers from HRBC and SRBC lipids, demonstrating that in the latter neither microvesicle release or lipid extraction occurred. Our results demonstrate that the volume expansion of erythrocytes is not the only mechanism responsible for the protection by surfactants against hypotonic hemolysis: volume expansion could be compensated via microvesicle release or by the extraction of membrane components upon collisions between red blood cells and surfactant aggregates depending on the membrane composition., (Copyright © 2018 Elsevier B.V. All rights reserved.)