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Purpose. Gestational trophoblastic disease (GTD) coexisting with a steadily progressing pregnancy is an extremely rare condition presented in the literature as a single case or case series of successful delivery. The purpose of this study was to describe five cases of GTD and present possible management strategies for such patients. Methods. Clinical data of five pregnancies with coexisting GTD were identified within the Almazov National Medical Research Centre from 2018 to 2021. Results. Three cases of multiple pregnancies with complete hydatidiform moles and two cases of singleton pregnancies with intraplacental choriocarcinoma and invasive hydatidiform moles were identified. Three pregnancies were prolonged and ended with preterm deliveries. Malignant transformation of the GTD accounted for 60% of the cases. The condition of newborns was based on the level of prematurity and functional immaturity, and in all cases, it was aggravated by anemia. Conclusion. GTD coexisting with progressing pregnancy is threatened by the risks of preterm delivery, miscarriage, hemorrhage, and disease progression and requires monitoring in a multidisciplinary clinic experienced in the management of patients with malignant tumors during pregnancy. In cases of prolonged pregnancy against the background of GTD, we suggest the following monitoring during pregnancy: pelvic, abdominal ultrasound/MRI (without contrast), prenatal invasive fetal karyotype testing in cases of singleton pregnancy, lung X-ray/CT with uterine shielding, weekly assessment of β-hCG levels, and dynamic monitoring of the fetus. The following postnatal monitoring should be performed: morphological examination of the placenta, weekly assessment of β-hCG levels up to normalization, then monthly assessment up to six months, and control of β-hCG level of the newborn. [ABSTRACT FROM AUTHOR]

Summary: Wiskott–Aldrich syndrome (WAS) is an X‐linked recessive disorder caused by WAS gene mutations resulting in haematopoietic/immune cell defects. Recent studies report accelerated death of WAS platelets and lymphocytes. Data on megakaryocyte (MK) maturation, viability and their possible role in thrombocytopenia development in WAS are limited. In this study we evaluate the MK viability and morphology in untreated, romiplostim‐treated WAS patients compared with normal controls. The study included 32 WAS patients and 17 healthy donors. MKs were captured from bone marrow aspirates by surface‐immobilized anti‐GPIIb‐IIIa antibody. Viability (by phosphatidylserine [PS] externalization), distribution by maturation stages and size of MK were determined by light microscopy. MK distribution by maturation stages in patients differed from controls. 40 ± 22% of WAS MKs versus 23 ± 11% of normal MKs were at maturation stage 3 (p = 0.02), whereas 24 ± 20% in WAS and 39 ± 14% in controls had megakaryoblast morphology (p = 0.05). Romiplostim treatment changed the MK maturation stages distribution close to normal. PS‐positive (PS+) MK in WAS was significantly higher (21 ± 21%) than in healthy controls (2 ± 4%, p < 0.01). WAS patients with more damaging truncating mutations and higher disease score had higher PS+ MK fraction (Spearman r = 0.6, p < 0.003). We conclude that WAS MKs have increased cell death tendency and changes in maturation pattern. Both could contribute to thrombocytopenia in WAS patients. [ABSTRACT FROM AUTHOR]

Plasma provides specific adjustment of solid‐state surface properties offering an alternative to high temperature treatment. Herein, hydrogen plasma treatment of monocrystalline (0001) ZnO surface is studied in an inductively coupled plasma reactor with reduced capacitively coupled plasma mode. The crucial role of electrical grounding of the sample holder for plasma etching and related changes in the morphology, optical, and electrical properties of surfaces exposed to electron and ion bombardment are explained. The effects on the chemical composition of the surface are analyzed by X‐ray photoelectron spectroscopy (XPS), optical properties by photoluminescence spectroscopy, topography, roughness, and surface measurements by atomic force microscopy (AFM) and Kelvin probe force microscopy (KPFM). All methods show altered ZnO surface properties before and after plasma treatment strongly depending on the electrical potential of the holder. [ABSTRACT FROM AUTHOR]

Mathematics anxiety (MA) is negatively associated with mathematics performance. Although some aspects, such as mathematics self‐concept (M self‐concept), seem to modulate this association, the underlying mechanism is still unclear. In addition, the false gender stereotype that women are worse than men in mathematics can have a detrimental effect on women. The role that the endorsement of this stereotype (mathematics–gender stereotype (MGS) endorsement) can play may differ between men and women. In this study, we investigated how MA and mathematics self‐concept relate to arithmetic performance when considering one's MGS endorsement and gender in a large sample (n = 923) of university students. Using a structural equation modeling approach, we found that MA and mathematics self‐concept mediated the effect of MGS endorsement in both men and women. For women, MGS endorsement increased their MA level, while in men, it had the opposite effect (albeit weak). Specifically, in men, MGS endorsement influenced the level of the numerical components of MA, but, unlike women, it also positively influenced their mathematics self‐concept. Moreover, men and women perceived the questions included in the considered instruments differently, implying that the scores obtained in these questionnaires may not be directly comparable between genders, which has even broader theoretical and methodological implications for MA research. [ABSTRACT FROM AUTHOR]

A comparative study of structural, optical properties of plasma‐treated Ga‐doped ZnO nanorods (GZO NRs) prepared by hydrothermal growth is presented, which provides an economical technology for fast production. Annealing in air followed by plasma treatment has been found to be an effective way of purification of ZnO NRs. The plasma hydrogenation and oxidation are done at room temperature in an inductively coupled plasma (ICP) reactor. The properties of plasma‐treated GZO NRs are investigated using various characterization methods, such as scanning electron microscopy (SEM), Raman, Fourier transform infrared (FTIR), X‐ray photoelectron spectroscopy (XPS), X‐ray diffraction (XRD), and electron paramagnetic resonance (EPR) spectroscopy. The SEM confirms the hexagonal shape of all GZO NRs. XPS reveals the presence of metallic Ga as well as Ga2O3 on GZO NRs surface. XRD has detected hexagonal (P63mc) ZnO phase in all samples with additional diffraction pattern in powder that has not been plasma treated. Plasma treatment does not affect the position of FTIR signals but changes the intensity of some absorption peaks. EPR shows a dominant signal with a g‐factor of 1.96. Plasma treatment of GZO samples affects its intensity. [ABSTRACT FROM AUTHOR]

Objective: In this narrative review, we summarize clinical and experimental data on the effect of light in migraine and discuss future prospects. Background: Effective nonpharmacological treatment of hypersensitivity to light in migraine is an unmet clinical need. Current management strategies primarily consist of seeking a dark room and avoiding light exposure. Advances in the past 2 decades have improved our understanding of the underlying pathophysiology of how migraine is influenced by light. This may provide promising avenues for novel approaches in clinical management. Methods: We searched MEDLINE for articles published from database inception up to September 1, 2021. We used the search term "migraine" with the search terms "light," "photophobia," "treatment," "trigger," "circadian rhythm," "environment," and/or "pathophysiology." Results: Light is commonly reported as a trigger factor of migraine attacks, however, early manifestation of photophobia and false attribution is likely the actual cause based on data deriving from retrospective, prospective, and experimental studies. The most common photophobia symptoms in migraine are exacerbation of headache by light and abnormal sensitivity to light with the underlying neural pathways likely being dependent on ongoing activity in the trigeminovascular system. Clinical studies and experimental models have identified mediators of photophobia and uncovered narrow wavebands of the light spectrum that may reduce pain intensity during a migraine attack. Consequently, novel devices have undergone exploratory clinical trials with promising results. Conclusion: False attribution is likely the reason why light is commonly reported as a trigger factor of migraine attacks, and a prospective confirmation is required to prevent unnecessary avoidance. The observation that individuals with migraine are not equally photophobic to all wavebands of the light spectrum opens the potential for innovative pain management strategies. In this context, using human‐centric lighting (also called integrative lighting) to mimic the natural daylight cycle and avoid harmful wavebands through modern technology may prove beneficial. Future research should identify direct and indirect consequences of light and other environmental factors in migraine to fill out knowledge gaps and enable evidence‐based care strategies within institutions, work environments, and other settings. [ABSTRACT FROM AUTHOR]

It is under debate whether the neural representation of numbers and letters might rely on distinct neural correlates, or on a mostly shared neural network. In the present study, a total of 47 children in fifth grade (Experiment 1) and sixth grade (Experiment 2) simply copied numbers and letters on a touch screen while brain activation changes were recorded by means of functional near‐infrared spectroscopy (fNIRS). fNIRS data of both experiments and a joint analysis revealed that a shared neural network, particularly in the left hemisphere, was activated in response to both number and letter copying. Interestingly, no difference was observed in brain activation patterns between these two stimuli, as revealed by Bayesian analysis. Our findings indicate that both number and letter copying lead to similar brain activation in children. We further suggest methodological and applied applications of these findings in the frame of educational neuroscience. [ABSTRACT FROM AUTHOR]

A major goal of education in elementary mathematics is the mastery of arithmetic operations. However, research on subtraction is rather scarce, probably because subtraction is often implicitly assumed to be cognitively similar to addition, its mathematical inverse. To evaluate this assumption, we examined the relation between the borrow effect in subtraction and the carry effect in addition, and the developmental trajectory of the borrow effect in children using a choice reaction paradigm in a longitudinal study. In contrast to the carry effect in adults, carry and borrow effects in children were found to be categorical rather than continuous. From grades 3 to 4, children became more proficient in two-digit subtraction in general, but not in performing the borrow operation in particular. Thus, we observed no specific developmental progress in place-value computation, but a general improvement in subtraction procedures. [ABSTRACT FROM AUTHOR]

The pulping industry could become a biorefinery if the lignin and hemicellulose components of the lignocellulose are valorized. Conversion of lignin into well-defined aromatic chemicals is still a major challenge. Lignin depolymerization reactions often occur in parallel with irreversible condensation reactions of the formed fragments. Here, we describe a strategy that markedly suppresses the undesired condensation pathways and allows to selectively transform lignin into a few aromatic compounds. Notably, applying this strategy to woody biomass at organosolv pulping conditions, the hemicellulose, cellulose, and lignin were separated and in parallel the lignin was transformed into aromatic monomers. In addition, we were able to utilize a part of the lignocellulose as an internal source of hydrogen for the reductive lignin transformations. We hope that the presented methodology will inspire researchers in the field of lignin valorization as well as pulp producers to develop more efficient biomass fractionation processes in the future. [ABSTRACT FROM AUTHOR]

Due to extraordinary properties and biocompatibility, diamond nanoparticles - nanodiamonds (NDs) are considered for various biomedical applications. Amongst other functional groups which may be grafted on the NDs surface, the amines (NH x) are highly demanded linkers for biomolecules and dyes. In this regard, a non-destructive, non-hazardous and low-cost method of NDs amination would further accelerate their industrial applications in biomedicine and life science. Here we present a study on NDs treatment using diffuse coplanar surface barrier discharge in the gas mixture H2:N2 = 1:1 at the atmospheric pressure. Detonation and high pressure-high temperature nanoparticles (D-NDs and HPHT-NDs) were used either as-received or air-annealed. The FTIR spectra confirmed the presence of N-H stretching vibrations for all kinds of NDs after the treatment. It was revealed by XPS and FTIR measurements that both kinds of D-NDs (as-received and air-annealed) exhibited higher content of −NH2 functions in the detected nitrogen groups than HPHT-NDs. The treatment of as-received D-NDs led to the conversion of −COOH groups to amides. A large increase of C-H bonds after the discharge treatment was found, especially for the annealed NDs forms. Raman spectroscopy revealed a decrease of sp2 carbon after the treatment of the as-received HPHT-NDs. [ABSTRACT FROM AUTHOR]

A model developed to predict aqueous solubility at different temperatures has been proposed based on quantitative structure-property relationships (QSPR) methodology. The prediction consists of two steps. The first one predicts the value of k parameter in the linear equation [ABSTRACT FROM AUTHOR]

The jet of reactive effluents produced by surface dielectric barrier discharge was used to deposit PEO-like plasma polymers from di(ethylene) glycol vinyl ether. The jet was confined within the hollow space of either circular cross-section with substrate placed perpendicular to the jet, or rectangular cross-section with the walls used as substrates. The best 67% retention of the ethers was obtained for the circular channel, whereas it was only 50% for the rectangular channel. In the latter case, deposition at longer distances was possible. In both cases, the deposition started with the formation of islands that grew, coalesced and eventually built up a continuous coating. [ABSTRACT FROM AUTHOR]

RATIONALE: Mass spectrometry has shown itself to be the most efficient tool for the sequencing of peptides. However, de novo sequencing of novel natural peptides is significantly more challenging in comparison with the same procedure applied for the tryptic peptides. To reach the goal in this case it is essential to select the most efficient methods of triggering fragmentation and combine all the possible complementary techniques. METHODS: Collision-induced dissociation (CID), high-energy collision dissociation (HCD), and electron-transfer dissociation (ETD) tandem mass spectra recorded with a LTQ Orbitrap Velos instrument were used for the elucidation of the sequence of the natural non-tryptic peptides from the skin secretion of Rana latastei. Manual interpretation of the spectra was applied. RESULTS: The combined approach using CID, HCD, and ETD tandem mass spectra of the multiprotonated peptides in various charge states, as well as of their proteolytic fragments, allowed the sequences of seven novel peptides from the skin secretion of Rana latastei to be established. CONCLUSIONS: Manual mass spectrometry sequencing of natural non-tryptic peptides from the skin secretion of Rana latastei provided the opportunity to work successfully with these species and demonstrated once again its advantage over automatic approaches. [ABSTRACT FROM AUTHOR]

Due to an extraordinary combination of intrinsic properties of diamond nanoparticles (DNPs), there is an increased demand for their usage in various areas. While a broad range of surface termination is often done by wet-chemical, UV-irradiation or plasma treatments, DNPs hydrogenation is still an open issue. Thermal annealing or microwave plasma treatment, both known as high-temperature processes, do not offer satisfactory solutions for DNPs hydrogenation. Here, we report on a new approach for plasma-assisted DNPs hydrogenation at temperatures below 100 °C. As-received detonation DNPs with size about 5 nm were annealed (oxidized) in air at 450 °C for 30 min to reduce non-diamond carbon content. Then the annealed DNPs were plasma treated using atmospheric-pressure diffuse coplanar surface barrier discharge in pure hydrogen at powers densities of 1.8 and 3.1 W/cm2. While infrared spectra of annealed DNPs were dominated by oxygen containing functional groups, plasma-hydrogenated DNPs revealed increase of bands of CH stretching vibrations in the region of 2800-3000 cm−1 with only 5 min of plasma treatment. Prolonged plasma treatments up to 60 min resulted in the increase of CH stretching vibrations and a decrease of COC groups in the spectral region of 1000-1300 cm−1. [ABSTRACT FROM AUTHOR]

Nanocrystalline diamond (NCD) films may be used in biosensing after modification of their surfaces with active functional groups. Here, surface functionalization of O- and H-NCD films with amine groups was made by 2 plasma-based processes: a) RF plasma treatment in ammonia, b) the deposition of thin amine-containing plasma polymer via RF magnetron sputtering of nylon target in Ar/N2 mixture. Amination of the NCD films by plasma treatment in NH3 caused an attachment of 1% of primary amines but destroyed the surface conductivity of H-NCD films. The 5% concentration of NH2 was detected on the NCD covered with the plasma polymer. Moreover, the surface conductivity of H-NCD films reached 10−7 S. [ABSTRACT FROM AUTHOR]

Novel experimental methods, including a modified single fiber in vitro motility assay, X-ray diffraction experiments, and mass spectrometry analyses, have been performed to unravel the molecular events underlying the aging-related impairment in human skeletal muscle function at the motor protein level. The effects of old age on the function of specific myosin isoforms extracted from single human muscle fiber segments, demonstrated a significant slowing of motility speed ( P < 0.001) in old age in both type I and IIa myosin heavy chain (My HC) isoforms. The force-generating capacity of the type I and IIa My HC isoforms was, on the other hand, not affected by old age. Similar effects were also observed when the myosin molecules extracted from muscle fibers were exposed to oxidative stress. X-ray diffraction experiments did not show any myofilament lattice spacing changes, but unraveled a more disordered filament organization in old age as shown by the greater widths of the 1, 0 equatorial reflections. Mass spectrometry ( MS) analyses revealed eight age-specific myosin post-translational modifications ( PTMs), in which two were located in the motor domain (carbonylation of Pro79 and Asn81) and six in the tail region (carbonylation of Asp900, Asp904, and Arg908; methylation of Glu1166; deamidation of Gln1164 and Asn1168). However, PTMs in the motor domain were only observed in the IIx My HC isoform, suggesting PTMs in the rod region contributed to the observed disordering of myosin filaments and the slowing of motility speed. Hence, interventions that would specifically target these PTMs are warranted to reverse myosin dysfunction in old age. [ABSTRACT FROM AUTHOR]

RATIONALE Mass spectrometry has shown itself as the most efficient tool for the sequencing of peptides. However, de novo sequencing of novel natural peptides is significantly more challenging in comparison with the same procedure applied for the tryptic peptides. To reach the goal in this case it is essential to select the most useful methods of triggering fragmentation and combine complementary techniques. METHODS Comparison of low-energy collision-induced dissociation (CID) and higher energy collision-induced dissociation (HCD) modes for sequencing of the natural non-tryptic peptides with disulfide bonds and/or several proline residues in the backbone was achieved using an LTQ FT Ultra Fourier transform ion cyclotron resonance (FTICR) mass spectrometer (Thermo Fisher Scientific, Bremen, Germany) equipped with a 7 T magnet and an LTQ Orbitrap Velos ETD (Thermo Fisher Scientific, Bremen, Germany) instrument. Peptide fractions were obtained by high-performance liquid chromatography (HPLC) separation of frog skin secretion samples from ten species of Rana temporaria, caught in the Kolomna district of Moscow region (Russia). RESULTS HCD makes the b/y series longer and more pronounced, thus increasing sequence coverage. Fragment ions due to cleavages at the C-termini of proline residues make the sequencing more reliable and may be used to detect missed cleavages in the case of tryptic peptides. Another HCD peculiarity involves formation of pronounced inner fragment ions (secondary ynbm ion series formed from the abundant primary y-ions). Differences in de novo sequencing of natural non-tryptic peptides with CID and HCD, involving thorough manual expert interpretation of spectra and two automatic sequencing algorithms, are discussed. CONCLUSIONS Although HCD provides better results, a combination of CID and HCD data may notably increase reliability of de novo sequencing. Several pairs of b2 /a2-ions may be formed in HCD, complicating the spectra. Automatic de novo sequencing with the available programs remains less efficient than the manual one, independently of the collision energy Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Key points Weaning from mechanical ventilation (MV) of long-term intensive care unit (ICU) patients is delayed by impaired respiratory muscle function; however, the mechanisms that cause the impairment are not fully understood., A novel experimental rat ICU model was used for time-resolved analyses (6 h to 2 weeks) of the effects of MV on diaphragm muscle fibre structure and function, and on gene and protein expression., A prompt and progressive decline of diaphragm muscle fibre function, preceding atrophy, occurred with MV, and at the end of 2 weeks residual diaphragm muscle fibre function was <15% of control levels., Cellular and subcellular analyses indicated that oxidative stress-triggered protein modifications had significantly diminished diaphragm muscle fibre function., The novel finding that activation of proteolytic pathways and regulation of contractile protein synthesis were different in diaphragm and limb muscles has direct implications for the design of muscle-specific intervention strategies., Abstract Controlled mechanical ventilation (CMV) plays a key role in triggering the impaired diaphragm muscle function and the concomitant delayed weaning from the respirator in critically ill intensive care unit (ICU) patients. To date, experimental and clinical studies have primarily focused on early effects on the diaphragm by CMV, or at specific time points. To improve our understanding of the mechanisms underlying the impaired diaphragm muscle function in response to mechanical ventilation, we have performed time-resolved analyses between 6 h and 14 days using an experimental rat ICU model allowing detailed studies of the diaphragm in response to long-term CMV. A rapid and early decline in maximum muscle fibre force and preceding muscle fibre atrophy was observed in the diaphragm in response to CMV, resulting in an 85% reduction in residual diaphragm fibre function after 9-14 days of CMV. A modest loss of contractile proteins was observed and linked to an early activation of the ubiquitin proteasome pathway, myosin:actin ratios were not affected and the transcriptional regulation of myosin isoforms did not show any dramatic changes during the observation period. Furthermore, small angle X-ray diffraction analyses demonstrate that myosin can bind to actin in an ATP-dependent manner even after 9-14 days of exposure to CMV. Thus, quantitative changes in muscle fibre size and contractile proteins are not the dominating factors underlying the dramatic decline in diaphragm muscle function in response to CMV, in contrast to earlier observations in limb muscles. The observed early loss of subsarcolemmal neuronal nitric oxide synthase activity, onset of oxidative stress, intracellular lipid accumulation and post-translational protein modifications strongly argue for significant qualitative changes in contractile proteins causing the severely impaired residual function in diaphragm fibres after long-term mechanical ventilation. For the first time, the present study demonstrates novel changes in the diaphragm structure/function and underlying mechanisms at the gene, protein and cellular levels in response to CMV at a high temporal resolution ranging from 6 h to 14 days. [ABSTRACT FROM AUTHOR]

A series of high quality Fe xGa1− xBO3 single crystals with 0 ≤ x ≤ 1 was prepared and studied by electron magnetic resonance in the temperature range from 4 to 290 K. At low x, only the electron paramagnetic resonance (EPR) of diluted Fe3+ ions is present. The EPR spectra for different orientations of the magnetizing field have been computer simulated. With a conventional spin Hamiltonian including the Zeeman and fine-structure terms, two different sets of best-fit parameters have been found. This ambiguity has been resolved on the basis of the general spin Hamiltonian with parameters determined from the crystallographic data using the Newman superposition model. A detailed fitting to the experimental EPR spectra assuming statistical distributions of Fe3+ ligand coordinates has revealed the existence of a certain degree of local disorder in Fe xGa1− xBO3 single crystals. [ABSTRACT FROM AUTHOR]

L8123 --> 805.26 --> Dictyostelium discoideum is a social amoeba commonly used as a model organism in cellular migration studies. Dictyostelium adhesion is mediated by nonspecific interactions, such as Van der Waals forces, as well as specific protein‐mediated interactions between the cell and the substrate. Since adhesive properties of this organism affect its motility, finding ways to manipulate its nonspecific or specific interactions can be useful for future migration experiments. We tested the effects of bovine serum albumin (BSA), which is known to affect nonspecific binding via its interference with electrostatic interactions, on Dictyostelium adhesion. Bacterially‐grown wild‐type cells had increased adhesion when plated on 3% BSA, while axenically‐grown cells exhibited a decrease in adhesion on BSA. To explore why BSA has differential effects on adhesion of Dictyostelium grown under different conditions we tested adhesion of cells lacking one of the specific mediators of attachment, Talin A (TalA). Unlike wild‐type cells, both axenically and bacterially‐grown TalA‐null cells had decreased adhesion on BSA. These data suggest that BSA effects on adhesion may be dependent on TalA in bacterially‐grown cells. Alternatively, since TalA‐null cells have an impaired ability to phagocytose, they may behave more like axenically‐grown cells even when grown on bacteria. In this case, differential effects of BSA may be due to the inherent differences in the adhesion mechanism of cells grown under axenic vs. bacterially‐fed conditions. We are currently examining these possibilities. [ABSTRACT FROM AUTHOR]

L8049 --> 805.20 --> Molecular mechanisms by which cells sense and directionally migrate in response to mechanical perturbation, which is critical in homeostasis and many diseases, are not well understood. Dictyostelium discoideum cells exposed to a brief burst of shear flow show rapid and transient activation of multiple components of the signal transduction network that participates in directed migration of these cells. Previous data from our laboratory demonstrated that actin crosslinking protein filamin is involved in the ability of cells to respond to shear flow. We also found that the actin‐binding domain is required for filamin's function in this context. To determine if the dimerization domain (DD) is also required for filamin's role in sensing/transmitting mechanical stimuli we generated a truncation construct of filamin lacking DD (FLNΔDD) and expressed it in wild‐type or filamin‐null cells. We found that FLNΔDDwas able to relocalize to the cortex of both wild‐type and filamin‐null cells following 2‐sec stimulation with shear flow, suggesting that dimerization between filamin molecules is not required for their recruitment to the cortex. To detect activation of the signal transduction network in the presence or absence of FLNΔDD, we used fluorescently‐tagged Ras binding domain biosensor that detects active Ras and was previously shown to relocalize to the cortex following mechanical stimulation. Surprisingly, FLNΔDDwas able to rescue the reduced response of filamin‐null cells to shear flow stimulation, suggesting that dimerization of filamin may not be needed for its ability to sense or transmit mechanical cues. However, the presence of FLNΔDD may also alter the overall organization of the cytoskeletal network, potentially explaining changes in mechanotransduction. We are currently investigating these possibilities. [ABSTRACT FROM AUTHOR]

L7777 --> 664.17 --> Dictyostelium discoideum is a social amoeba commonly used as a model organism for the study of various cellular processes, including directed cell migration. Mechanical cues, such as shear flow, have the ability to induce directed migration. However, little is known about the role of cell‐substrate adhesion in mechanotransduction of D. discoideum. We hypothesized that adhesion is essential for the ability of cells to sense and respond to mechanical cues. To test this hypothesis, we examined whether mechanotransduction depends on SibA, a transmembrane protein involved in the adhesion of D. discoideum. Before testing cell response to shear flow, we studied the adhesion of SibA‐null cells grown under our experimental conditions. Adhesion of SibA‐null cells in growth media was significantly reduced compared to wild‐type cells, consistent with previously published findings. Notably, adhesion was significantly decreased by 25% in SibA‐null compared to wild‐type cells grown on a bacterial lawn, which is the growth method used prior to the assessment of response to shear flow. To test how SibA‐null cells respond to acute mechanical stimulation, we examined the localization of active Ras as a read‐out of the activation of the signal transduction network involved in directed migration. Both wild‐type and SibA‐null cells had a comparable response to 2‐second stimulation with shear flow at two different pressures. These findings suggest that the modest reduction in adhesion observed in SibA‐null cells did not affect the ability of cells to respond to shear flow stimulation. Whether more substantial changes in adhesion would perturb mechanotransduction in this system remains to be examined. [ABSTRACT FROM AUTHOR]

In this paper we offer a novel approach for the structural interpretation of QSAR models. The major advantage of our developed methodology is its universality, i.e., it can be applied to any QSAR/QSPR model irrespective of chemical descriptors and machine learning methods applied. This universality was achieved by using only the information obtained from substructures of the compounds of interest to interpret model outcomes. Reliability of the offered approach was confirmed by the results of three case studies, including end-points of different types (continuous and binary classification) and nature (solubility, mutagenicity, and inhibition of Transglutaminase 2), various fragment and whole-molecule descriptors (Simplex and Dragon), and multiple modeling techniques (partial least squares, random forest, and support vector machines). We compared the global contributions of molecular fragments obtained using our methodology with known SAR rules derived experimentally. In all cases high concordance between our interpretation and results published by others was observed. Although the proposed interpretation approach could be easily extended to any type of descriptors, we would recommend using Simplex descriptors to achieve a larger variety of investigated molecular fragments. The developed approach is a good tool for interpretation of such 'black box' models like random forest, neural networks, etc. Analysis of fragment global contributions and their deviation across a dataset could be useful for the identification of key fragments and structural alerts. This information could be helpful to maximize the positive influence of structural surroundings on the given fragment and to decrease the negative effects. [ABSTRACT FROM AUTHOR]

Key points The ageing-related impairment of muscle function and consequent falls and fall-related injuries have severe negative effects on morbidity and mortality in old age, with women being more negatively affected than men., The effects of hormone replacement therapy (HRT) on regulation of muscle contraction and myonuclear organization were investigated in monozygous postmenopausal twin pairs where only one twin was an HRT-user., HRT treatment improved single fibre force-generating capacity (specific force), without affecting fibre size and speed of contraction, due to fibre type-specific effects on force and number of force-generating cross-bridges., HRT had a significant effect on the myonuclear organization in slow-twitch muscle fibres, improving the synthetic capacity of the myonuclei and optimizing transport of proteins., Significant positive effects on regulation of muscle contraction and myonuclear organization were observed at the cellular level in response to HRT with consequences for quality of life in postmenopausal women., Abstract Ageing is associated with a decline in muscle mass and strength leading to increased physical dependency in old age. Postmenopausal women experience a greater decline than men of similar age in parallel with the decrease in female sex steroid hormone production. We recruited six monozygous female twin pairs (55-59 years old) where only one twin pair was on hormone replacement therapy (HRT use = 7.8 ± 4.3 years) to investigate the association of HRT with the cytoplasmic volume supported by individual myonuclei (myonuclear domain (MND) size,) together with specific force at the single fibre level. HRT use was associated with a significantly smaller (∼27%; P < 0.05) mean MND size in muscle fibres expressing the type I but not the IIa myosin heavy chain (MyHC) isoform. In comparison to non-users, higher specific force was recorded in HRT users both in muscle fibres expressing type I (∼27%; P < 0.05) and type IIa (∼23%; P < 0.05) MyHC isoforms. These differences were fibre-type dependent, i.e. the higher specific force in fast-twitch muscle fibres was primarily caused by higher force per cross-bridge while slow-twitch fibres relied on both a higher number and force per cross-bridge. HRT use had no effect on fibre cross-sectional area (CSA), velocity of unloaded shortening ( V0) and relative proportion of MyHC isoforms. In conclusion, HRT appears to have significant positive effects on both regulation of muscle contraction and myonuclei organization in postmenopausal women. [ABSTRACT FROM AUTHOR]

This study highlights the possibility to control materials' chemistry simultaneously at the atomic and micrometric scales and to design functional oxide-based multimaterials, thanks to the specificity of Spark Plasma Sintering ( SPS). We have used a dual synthesis route, namely chemical and composite, combined with SPS to adjust the oxidation state of intrinsic and dopant ions, the grain boundaries state, and to control interdiffusion in composites made of Mn-doped Ba0.6 Sr0.4 TiO3 ( BST) and MgO. At the atomic level, the Mn substituent valence state can be fixed according to the sintering process: Electron Paramagnetic Resonance evidenced [ABSTRACT FROM AUTHOR]

This paper is devoted to the development of methodology for QSPR modeling of mixtures and its application to vapor/liquid equilibrium diagrams for bubble point temperatures of binary liquid mixtures. Two types of special mixture descriptors based on SiRMS and ISIDA approaches were developed. SiRMS-based fragment descriptors involve atoms belonging to both components of the mixture, whereas the ISIDA fragments belong only to one of these components. The models were built on the data set containing the phase diagrams for 167 mixtures represented by different combinations of 67 pure liquids. Consensus models were developed using nonlinear Support Vector Machine (SVM), Associative Neural Networks (ASNN), and Random Forest (RF) approaches. For SVM and ASNN calculations, the ISIDA fragment descriptors were used, whereas Simplex descriptors were employed in RF models. The models have been validated using three different protocols: 'Points out', 'Mixtures out' and 'Compounds out', based on the specific rules to form training/test sets in each fold of cross-validation. A final validation of the models has been performed on an additional set of 94 mixtures represented by combinations of novel 34 compounds and modeling set chemicals with each other. The root mean squared error of predictions for new mixtures of already known liquids does not exceed 5.7 K, which outperforms COSMO-RS models. Developed QSAR methodology can be applied to the modeling of any nonadditive property of binary mixtures (antiviral activities, drug formulation, etc.) [ABSTRACT FROM AUTHOR]

This paper considers design of microstrip MIMO antennas for an LTE/WiMAX USB dongle operating in the 2.5-2.7 GHz frequency band. The MIMO system includes two antenna elements with an additional requirement of high isolation between them that is especially difficult to realize due to size limitations of a USB dongle. Three approaches to achieve the needed system characteristics using microstrip PCB antennas are proposed. For the first design, high port-to-port isolation is achieved by using a decoupling techniques based on a direct connection of the antenna elements. For the second approach, high port-to-port isolation of the MIMO antenna system is realized by a lumped decorrelation capacitance between antenna elements feeding points. The third proposed antenna system does not use any special techniques, and high port-to-port isolation is achieved by using only the properties of a developed printed inverted-F antenna element. The designed MIMO antenna systems have the return loss S11 and the insertion loss S21 bandwidths of more than 200 MHz at the -8 dB level with the correlation coefficient lower than 0.1 and exhibit pattern diversity when different antenna elements are excited. Experimental measurements of the fabricated antenna systems proved the characteristics obtained from electromagnetic simulation. [ABSTRACT FROM AUTHOR]