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Densities for solutions of urea in aqueous mebicar (N -tetramethyl-substituted glycoluril) were measured using a hermetically sealed vibrating-tube densimeter, with an uncertainty of ~3.0 × 10−2 kg∙m−3, at T = (278.15, 288.15, 298.15, 308.15, and 318.15) K and p = (99.6 ± 0.8) kPa. The solution molality was ranged from (0.026 to 0.101) mol·kg−1 for the aqueous mebicar and from ca. (0.1 to 0.4) mol·kg−1 for the solute urea. The density data were used to calculate the apparent molar volumes and expansibilities (down to infinite dilution) for urea as a solute, as well as urea – urea and urea – mebicar pairwise interaction coefficients over the whole temperature range being chosen. The calorimetrically derived effects of urea dissolution in the aqueous mebicar at T = 298.15 K were also included in discussing. The results were compared with the previously obtained those for the similar ternary system (water + mebicar + glycine). It was concluded that the hydrophilic constituent (via H-bonding) are predominant in the solute – co-solute interaction effects and the mebicar has an overall stabilizing influence on the process of urea hydration. [Display omitted] • Densities of ternary (water + mebicar + urea) solutions were measured at T = (278.15 to 318.15) K and p = (99.6 ± 0.8) kPa. • Standard volumes and expansibilities of urea, volumes of its transfer and urea – mebicar interaction parameters were derived. • Urea – mebicar interactions were found to be mainly pairwise and hydrophilic in nature at the expense of forming H bonds. • Volume and enthalpy effects of solution showed mebicar has an overall stabilizing influence on the process of urea hydration. • Decrease in electrostriction at glycine-by-urea replacement in aqueous mebicar strengthens solute – co-solute interactions. [ABSTRACT FROM AUTHOR]

Densities of aqueous 1,1-dimethylurea (1,1-DMU) solutions, with a molality ranged up to 0.2 mol·kg−1, were measured using an Anton Paar DMA 5000 M vibrating-tube densimeter. All the experiments were performed with a density uncertainty did not exceeding 0.03 kg·m−3·in the temperature range between (278.15 and 318.15) K at pressure to be 99.6 ± 0.8 kPa. The standard (partial at infinite dilution) molar volumes and expansibilities of 1,1-DMU in water were derived from the density data. The influence of nature of N -dimethyl-substitution in urea and achiral glycoluril (bisurea) molecules on structure-packing effects at forming the hydration complex was discussed. A nontrivial fact of the similarity in changing both volume (δV 2 o) and enthalpy (δΔ sol H 2 o) effects of a solute dissolution in water during the isomeric replacements of 1,1-DMU → 1,3-dimethylurea and 2,8-dimethylglycoluril → 2,4-dimethyglycoluril was established. It was found that δV 2 o ~7 × 10−6 m3·mol−1 and δΔ sol H 2 o ~11 kJ·mol−1 at T = 298.15 K in both transfer cases considered. The comparability in differently overlapping thermodynamic effects during the dissolution process at the specified replacements can be the main cause for the phenomenon discovered. Unlabelled Image • Densities of dilute aqueous 1,1-dimethylurea (1,1-DMU) solutions were measured at T = (278.15 to 318.15) K and p = 99.6 kPa. • Standard molar volumes and expansibilities of 1,1-DMU in water were derived and compared with whose for isomeric 1,3-DMU. • Effect of dimethylation in urea and glycoluril (2,4- and 2,8-DMGU) on volume and enthalpy dissolution effects was discussed. • Similarity in thermodynamic effects of transfer at 1,1-DMU → 1,3-DMU and 2,8-DMGU → 2,4-DMGU replacements was established. • Comparability in differently overlapping effects during a dissolution process can be cause for the phenomenon discovered. [ABSTRACT FROM AUTHOR]

In this paper, we have discussed the results of densimetric and calorimetric studies of dissolution process in water for the (1:1) cocrystal consisting of two heterocyclic isomers being cis - and trans -coordinated dimethylglycolurils (2,8-DMGU and 2,6-DMGU, respectively) in the temperature range from (278.15 to 318.15) K at the ambient pressure. The standard (apparent or partial at infinite dilution) molar volumes and isobaric expansibilities of cocrystal as a solute in water were derived from the experimental data on solution density. Using thermochemical measurements, the standard molar enthalpies and isobaric heat capacities of the dissolution of cocrystal in water were also determined at the temperatures of interest. Based on the previously obtained similar results for aqueous 2,6-DMGU and 2,8-DMGU, a comparative analysis of packing and interaction changes in the hydration complex induced by the cocrystallization process has been carried out. It was found that the formation of cocrystal leads to a peculiar "synergism" in both volume and heat capacity effect of N,N ′-dimethylglycoluril hydration at all temperatures studied. • Densities of aqueous (1:1) cis-trans- dimethylglycoluril {cocrystal A + B } were measured at 278.15–318.15 K and ~0.1 MPa. • Standard molar enthalpies and heat capacities of cocrystal dissolution in water were derived under the same conditions. • The cocrystal formation leads to synergism in both volume and heat capacity effect of N,N ′-dimethylglycoluril hydration. • The cocrystal's hydration complex structure was found looser compared to that of each of its equimolecular constituents. • Standard molar heat capacities of solute hydration are distributed into a series: cis -isomer < trans- isomer < cocrystal. [ABSTRACT FROM AUTHOR]

Background: The International Classification of Headache Disorders diagnostic criteria for Headache Attributed to Transient Ischemic Attack (TIA) and many other secondary headaches are based primarily on the opinion of experts. The aim of this study was to field test, for the first time, the diagnostic criteria for headache attributed to TIA of the International Classification of Headache Disorders, 3rd edition (ICHD-3) and in case of their weaknesses to propose new diagnostic criteria. Methods: Consecutive patients with Transient Ischemic Attack and a simultaneous control group were extensively interviewed soon after admission. Data were collected on previous headaches, headaches around the time of Transient Ischemic Attack and characteristics of the TIA using validated neurologist conducted semi-structured interview forms. The evidence of relevant infarction were excluded in patients with Transient Ischemic Attack using magnetic resonance imaging with diffusion-weighted imaging (n = 112) or computed tomography (n = 8). Results: One hundred twenty patients with Transient Ischemic Attack and 192 controls were included. A new type of headache occurred within 24 h in 16 (13%) of patients with Transient Ischemic Attack and in no controls, a preexisting type of headache with altered characteristics occurred in 9 (7.5%) of patients with Transient Ischemic Attack and no in controls, headache without altered characteristics occurred in 8 (6.6%) of patients with Transient Ischemic Attack and in 9 (4.6%) controls. Only 24% of the headaches in patients with Transient Ischemic Attack (8 of 33 patients) fulfilled the diagnostic criteria of International Classification of Headache Disorders-3 and no control patients. We propose new criteria fulfilled by 94% of the headaches. Specificity remained excellent as only one of 192 controls had a headache fulfilling the proposed criterion C. Conclusions: Existing diagnostic criteria for headache attributed to TIA of the International Classification of Headache Disorders are too insensitive. We suggest new diagnostic criteria with high sensitivity and preserved specificity. [ABSTRACT FROM AUTHOR]

Background: Headache is a common feature in acute cerebrovascular disease but no studies have evaluated the prevalence of specific headache types in patients with transient ischemic attacks (TIA). The purpose of the present study was to analyze all headaches within the last year and the last week before TIA and at the time of TIA.Methods: Eligible patients with TIA (n = 120, mean age 56.1, females 55%) had focal brain or retinal ischemia with resolution of symptoms within 24 h without presence of new infarction on MRI with DWI (n = 112) or CT (n = 8). All patients were evaluated within one day of admission by a single neurologist. As a control group we used patients (n = 192, mean age 58.7, females 64%) admitted with diagnoses “lumbago”, “lumbar spine osteochondrosis” or “gastrointestinal ulcer”.Results: One-year prevalence of migraine without aura was significantly higher in TIA patients than in controls: 20.8% and 7.8% respectively (p = 0.002, OR 3.1, 95% CI 1.6-6.2). 22 patients (18.3%) had sentinel or warning headache within the last week before TIA. At the time of TIA a new type of headache was observed in 16 patients (13.3%). No controls had a new type of headache. 12 of these 16 patients had migraine-like headache, 8 patients had tension-type-like headache and one patient thunderclap headache. Posterior circulation TIA was associated with headaches within last week before TIA and at the time of TIA much more frequently than anterior circulation TIA.Conclusions: The one year prevalence of migraine was significantly higher in TIA patients than in controls and so was the prevalence of headache within the last week before TIA and at the time of TIA. A previous headache that worsens and a new type of headache can be a warning of impending TIA. [ABSTRACT FROM AUTHOR]

• Densities of urea and tetramethylurea solutions in ethylene glycol were measured at (288.15–328.15) K and p = 99.6 kPa. • Standard partial molar volumes and isobaric expansibilities and pair interaction coefficients for solutes were computed. • A structure packing of solvation complex becomes denser on going from TMU to U and, in a less degree, from EG to water. • Coefficients of solute – solute interactions are positive for U and negative for TMU in EG, decreasing with temperature. • Temperature has differentiating effect on trends of changing standard partial expansibility of U and TMU as solutes in EG. The densities of urea (U) and tetramethylurea (TMU) solutions in ethylene glycol (EG) at the solute molality range up to 1.5 mol·kg−1 were measured with the uncertainty of 0.03 kg·m−3 at T = (288.15, 298.15, 308.15, 318.15 and 328.15) K and p = 99.6 kPa using a vibrating-tube densimeter. The standard partial molar volumes and isobaric expansibilities as well as parameters of the solvent-induced solute–solute pair interactions for both ureas were calculated. The results were discussed in terms of hydrophilic and hydrophobic nature of U and TMU, respectively, and also on the background of the suggestion that EG, like liquid water, forms the hydrogen bond spatial network. [ABSTRACT FROM AUTHOR]

Background and purpose: Hormonal replacement therapy (HRT) is used for symptomatic treatment of menopause. Some evidence suggests a proconvulsant effect of estrogen and an anticonvulsant role of progesterone. Thus, the use of exogenous sex steroid hormones might influence the course of epilepsy in peri‐ and postmenopausal women with epilepsy (WWE). We conducted a systematic review on the impact of HRT on the frequency of seizures of WWE. Methods: PubMed and Scopus were searched for articles published from inception until August 2022. Abstracts from the past 5 years from the European Academy of Neurology and European Epilepsy Congresses were also reviewed. Article reference lists were screened, and relevant articles were retrieved for consultation. Interventional and observational studies on WWE and animal models of estrogen deficiency were included. Critical appraisal was performed using the revised Cochrane risk‐of‐bias tool for randomized trials and ROBINS‐E tool. Results: Of 497 articles screened, 13 studies were included, including three human studies. One cross‐sectional study showed a decrease in seizure frequency in WWE using combined HRT, a case–control study showed an increase in comparison with controls, and a randomized clinical trial found a dose‐dependent increase in seizure frequency in women with focal epilepsy taking combined HRT. Ten studies addressing the impact of HRT in rat models were also included, which showed conflicting results. Conclusions: There is scarce evidence of the impact of HRT in WWE. Further studies should evaluate the harmful potential, and prospective registries are needed for monitoring this population. [ABSTRACT FROM AUTHOR]

The discovery of ammonia-oxidizing archaea (AOA) of the phylum Thaumarchaeota and the high abundance of archaeal ammonia monooxygenase subunit A encoding gene sequences in many environments have extended our perception of nitrifying microbial communities. Moreover, AOA are the only aerobic ammonia oxidizers known to be active in geothermal environments. Molecular data indicate that in many globally distributed terrestrial high-temperature habits a thaumarchaeotal lineage within the Nitrosopumilus cluster (also called “marine” group I.1a) thrives, but these microbes have neither been isolated from these systems nor functionally characterized in situ yet. In this study, we report on the enrichment and genomic characterization of a representative of this lineage from a thermal spring in Kamchatka. This thaumarchaeote, provisionally classified as “Candidatus Nitrosotenuis uzonensis”, is a moderately thermophilic, non-halophilic, chemolithoautotrophic ammonia oxidizer. The nearly complete genome sequence (assembled into a single scaffold) of this AOA confirmed the presence of the typical thaumarchaeotal pathways for ammonia oxidation and carbon fixation, and indicated its ability to produce coenzyme F420 and to chemotactically react to its environment. Interestingly, like members of the genus Nitrosoarchaeum, “Candidatus N. uzonensis” also possesses a putative artubulin-encoding gene. Genome comparisons to related AOA with available genome sequences confirmed that the newly cultured AOA has an average nucleotide identity far below the species threshold and revealed a substantial degree of genomic plasticity with unique genomic regions in “Ca. N. uzonensis”, which potentially include genetic determinants of ecological niche differentiation. [ABSTRACT FROM AUTHOR]

Background: Direct comparisons of the tolerability and safety of migraine preventive treatments targeting the calcitonin gene-related peptide pathway are lacking. This study aimed to compare the safety and tolerability of anti-calcitonin gene-related peptide monoclonal antibodies and gepants in migraine prevention. Methods: A network meta-analysis of phase 3 randomized controlled trials assessing the safety and tolerability of anticalcitonin gene-related peptide monoclonal antibodies (erenumab, eptinezumab, fremanezumab, or galcanezumab) and gepants (atogepant, rimegepant) in migraine prevention was performed. Primary outcomes were treatment-emergent adverse events and serious adverse events. Secondary outcomes included any adverse events, adverse events leading to treatment discontinuation and individual adverse events. Results: We included 19 randomized controlled trials, comprising 14,584 patients. Atogepant 120mg (OR 2.22, 95% CI [1.26, 3.91]) and galcanezumab 240 mg (OR 1.63, 95% CI [1.33, 2.00]) showed the largest odds of treatment-emergent adverse events compared to placebo. While eptinezumab 30 mg had greater odds of adverse events leading to treatment discontinuation (OR 2.62, 95% CI [1.03,6.66]). No significant differences in serious adverse events were found between active treatments and placebo. Eptinezumab was associated with the lowest odds of treatment-emergent adverse events and serious adverse events compared to placebo, whereas erenumab was associated with the lowest odds of any adverse events and quarterly fremanezumab with the lowest odds of treatment discontinuation due to adverse events. Conclusion: Monoclonal antibodies targeting the calcitonin gene-related peptide pathway and gepants are a safe and well tolerated option for migraine prevention. [ABSTRACT FROM AUTHOR]

Densities of highly dilute solutions of protiated and deuterated water in N,N-dimethylformamide and N,N-dimethylacetamide, with the solute mole fractions ranging up to 0.012, were measured with an error of 1.0 · 10−5 · cm3 · mol−1 at T = (278.15, 288.15, 298.15, 308.15 and 318.15) K and atmospheric pressure using a precise sealed vibrating-tube densimeter. Apparent molar volumes and apparent molar isobaric expansibilities (down to the infinite dilution) of water isotopologues were calculated. The temperature-dependent behavior of D2O–H2O solute isotope effects on the apparent molar quantities under study were described taking into account the structural features of the amide-solvating media compared. [Copyright &y& Elsevier]

Two millets, Panicum miliaceum and Setaria italica, were domesticated in northern China, around 6000 BC. Although its oldest evidence is in Asia, possible independent domestication of these species in the Caucasus has often been proposed. To verify this hypothesis, a multiproxy research program (Orimil) was designed to detect the first evidence of millet in this region. It included a critical review of the occurrence of archaeological millet in the Caucasus, up to Antiquity; isotopic analyses of human and animal bones and charred grains; and radiocarbon dating of millet grains from archaeological contexts dated from the Early Bronze Age (3500–2500 BC) to the 1st Century BC. The results show that these two cereals were cultivated during the Middle Bronze Age (MBA), around 2000–1800 BC, especially Setaria italica which is the most ancient millet found in Georgia. Isotopic analyses also show a significant enrichment in 13C in human and animal tissues, indicating an increasing C4 plants consumption at the same period. More broadly, our results assert that millet was not present in the Caucasus in the Neolithic period. Its arrival in the region, based on existing data in Eurasia, was from the south, without excluding a possible local domestication of Setaria italica. [ABSTRACT FROM AUTHOR]

The molar enthalpies of dissolution of 1,3,6,8-tetraazatricyclo[4.4.1.13,8]dodecane or TMDETA (tetramethylenediethylenetetramine: the teotropine pharmaceutical) in ordinary (H 2 O) and heavy (D 2 O) water were measured calorimetrically at T = (278.15, 288.15, 298.15, 308.15, and 318.15) K and p = 0.1 MPa. The standard molar enthalpies and heat capacities of TMDETA dissolution/hydration, along with D 2 O–H 2 O solvent isotope effects (IEs) in these quantities, were computed. Solution enthalpies and corresponding IEs were found to be negative, decreasing in magnitude as the temperature is rising. It was concluded that hydrophobic effects are the predominant part in the TMDETA hydration and they are enhanced in D 2 O and weakened going from TMDETA to its lower-molecular aminal derivative, hexamethylenetetramine (HMTA) being the known drug urotropine. Unlike the aqueous HMTA, the "dualistic" character of TMDETA hydration is less dependent on the initial structure state of a solvent isotopologue. The results of analyzing the contributions to the solvation enthalpy within the scope of Scaled Particle Theory showed that IEs in the enthalpy of TMDETA – water interaction and the solvent cavity formation is almost cancelling each other at T > 288.15 K. Unlabelled Image • Standard enthalpies of solution of tetramethylenediethylenetetramine (TMDETA) in H 2 O and D 2 O were determined by calorimetry. • Calorimetric experiments were performed at temperatures from 278.15 K to 318.15 K (with a step of 10 K) at ambient pressure. • Dissolution process is largely exothermic, decreasing with temperature, and the enthalpy-isotopic effect has a negative sign. • Standard molar heat capacity of solution of TMDETA in water is positive and increases with temperature and at going to D 2 O. • In spite of strong hydrogen bonding, hydrophobic effects play a dominating part in dualistic hydration process of TMDETA. [ABSTRACT FROM AUTHOR]

Does complete mechanical removal of the zona pellucida modify the outcome of transfer of vitrified–warmed human blastocysts? In a prospective randomized controlled study, 419 couples were allocated to either zona pellucida-free (n = 209) or zona intact (n = 210) vitrified–warmed embryo transfer. Main outcome measures included clinical pregnancy, implantation and ongoing pregnancy rates. Transfer of zona pellucida-free blastocysts resulted in clinical pregnancy, implantation and ongoing pregnancy rates (35,9%, 33,9% and 32,1%, respectively), similar to those achieved with zona intact control embryos (39%, 36,4% and 33,1%, respectively). Total mechanical removal of the zona pellucida did not affect the tested parameters of clinical outcomes. [ABSTRACT FROM AUTHOR]

Сationic poly((2-aminoethyl)-methacrylate– co - N -methyl-(2-aminoethyl)-methacrylate- co - N,N- dimethyl-(2-aminoethyl)-methacrylate) copolymers were synthesized by reversible addition-fragmentation chain transfer polymerization in a wide range of molar masses 16 , 000 < M , g mol - 1 < 130 , 000 and narrow dispersities. The copolymers were investigated by a wide range of characterization techniques such as sedimentation velocity, intrinsic viscosity, translation diffusion, asymmetric flow field-flow fractionation, as well as standard SEC and NMR analysis. As a result a matrix of self-consistent parametric macromolecular characteristics and the absolute molar masses were obtained. Consistent Kuhn-Mark-Houwink-Sakurada scaling relationships were found for 0.2 M NaCl water ( [ η ] = 0.002 × M 0.85 , s 0 = 0.0231 × M 0.41 , D 0 = 2 , 349 × M - 0.59 ) and 0.2 M NaOH water ( [ η ] = 0.022 × M 0.50 ) solvent system. The corresponding conformational characteristics of the macromolecules, that define the polymer behavior in solution – equilibrium rigidity and diameter of the polymer chain, were determined to be A = 4.3 nm and A = 1.1 nm for 0.2 M NaCl and 0.2 M NaOH respectively. Additionally, the anisotropic optical properties were studied by the flow birefringence revealing information about optical anisotropy of the monomer unit ( Δ a = - 1.5 × 10 - 25 cm 3 ). The presented study exemplifies the in-depth analytical characterization of cationic/charge polymers by the fundamental hydrodynamic approaches resolving the essential macromolecular characteristics and solution behavior. [ABSTRACT FROM AUTHOR]

Pharmaceutically relevant cationic linear poly(2-aminoethyl-methacrylate)s were synthesized by reversible addition-fragmentation chain transfer polymerization resulting in a homologous series of the homopolymers in a wide range of molar masses ( 10,000 < M < 130,000 g m o l − 1 ) and relatively narrow dispersities ( Ð : 1.3 ± 0.4 ). The polymers were studied in 0.2 M N a C l and 0.2 M N a O H in water, applying combined analytical approach comprising of complementary hydrodynamic and optical methods such as analytical ultracentrifugation, intrinsic viscosity, translation diffusion, flow birefringence and asymmetric flow field-flow fractionation (AF4) as well as standard characterization technique (SEC). The efforts were focused on the evaluation of solution (solvation), molecular (absolute molar masses), conformational (equilibrium rigidity, diameter of the polymer chain) and optical (anisotropy of optical polarizability of the monomer unit) characteristics of the polymers. Consequently the absolute values of the molar masses were determined by the sedimentation-diffusion analysis and AF4 resulting in well consistent results. The corresponding scaling relationships in 0.2 M N a C l water ( [ η ] = 0.0031 × M 0.83 ; s 0 = 0.0324 × M 0.39 ; D 0 = 3,909 × M − 0.64 ) show linear trends in whole range of molar masses revealing random coil conformation of the macromolecules. Conformational characteristics were determined in 0.2 M N a C l (equilibrium rigidity A = 5.3 ± 1.5 n m ) and 0.2 M N a O H ( A = 1.3 ± 0.1 n m ) revealing an influence of uncompensated charges on the polymer conformation. [ABSTRACT FROM AUTHOR]

Rare earth tantalates La0.075Ta2O5.113, Eu0.089Ta2O5.134 and Yb0.051Ta2O5.077 have been prepared by solid state reaction at P=7.0GPa and T=1050–1100°C and studied by X-ray diffraction, thermal analysis and electron microscopy. Low hydrated amorphous tantalum, lanthanum, europium and ytterbium hydroxides were used as starting materials. Aqueous as well as anhydrous compounds were obtained. Title tantalates are crystallized in the structure type of F–Ta2O5 [Zibrov et al. Russ. J. Inorg. Chem. 48 (2003) 464–471] [5]. The structure was refined by the Rietveld method from X-ray powder diffractometer data: La0.075Ta2O5.113, a=10.5099(2), b=7.2679(1), c=6.9765(1)Å, V=532.90(1)Å3, Z=6, space group Ibam; Eu0.089Ta2O5.134, a=10.4182(3), b=7.2685(1), c=6.9832(1)Å, V=528.80(2)Å3, Z=6, space group Ibam; Yb0.051Ta2O5.077, a=10.4557(2), b=7.3853(1), c=6.8923(1)Å, V=532.21(1)Å3, Z=6, space group Ibam. RE atoms do not replace the tantalum in its positions but the only water in the channels of the structure. Highly charged cations RE+3 compress the unit cell so that its volume becomes less than that of F–Ta2O5. Significant decrease of the unit cell volume after water removal from the structure is possible due to the puckering of pentagonal bipyramid layers and change of the corrugation angle in the layer. [ABSTRACT FROM AUTHOR]

Here we present a combined analytical study of a homological series of poly(2-(dimethylamino)-ethyl methacrylate)s (DMAEMA) and their corresponding with methyl iodide quaternized versions poly[2-(methacryloyloxy) ethyl] trimethyl-ammonium iodide]s (QDMAEMA) in a wide range of molar masses (~ 7 to ~ 300 k D a) and low dispersities (~ 1.1 to ~ 1.3). The polymers were studied predominantly in 0.2 M N a C l in water at T = 20. 0 ° C applying mutually reinforcing's set of hydrodynamic methods, such as, viscometry, analytical ultracentrifugation, dynamic light scattering, isothermal diffusion and size exclusion chromatography. The manuscript provide compulsory discussions on the evaluation of physically sound values of the molar masses, hydrodynamic sizes and conformations of the macromolecules in solution. Special attention is paid to the investigation of ion-specific interactions and their influence on the hydrodynamic and molecular characteristics. The conformation of polymer chains in solution was validated via the classical scaling equations showing θ-conditions – η = 0.055 M 0.47 ± 0.04 ; s = 0.006 M 0.50 ± 0.02 ; D = 1200 M - 0.50 ± 0.02 for the initial DMAEMAs polymer chains and thermodynamically good ones for the quaternized macromolecules characterized by η = 0.002 M 0.80 ± 0.04 ; s = 0.0133 M 0.45 ± 0.02 ; D = 1665 M − 0.55 ± 0.02 . The equilibrium rigidity was found to be visibly influenced by the overall electrostatic interactions and the presence of closely associated iodine ions to the quaternized polymer chains giving A = 4.4 n m in comparison to A = 2.4 n m for the initial macromolecules. Image 1 • The complete set of hydrodynamic and molecular characteristics is established. • The influence of the associated counterions on the molecular characteristics is shown. • The equilibrium rigidity for the quaternized DMAEMA is notably higher. [ABSTRACT FROM AUTHOR]

Background: Maturation of the mouse is accompanied by the increase in heart rate. However, the mechanisms underlying this process remain unclear. We performed an action potentials (APs) recordings in mouse sinoatrial node (SAN) true pacemaker cells and in silico analysis to clarify the mechanisms underlying pre-postnatal period heart rate changes., Results: The APs of true pacemaker cells at different stages had similar configurations and dV/dt max values. The cycle length, action potential duration (APD 90 ), maximal diastolic potential (MDP), and AP amplitude decreased, meanwhile the velocity of diastolic depolarization (DDR) increased from E12.5 stage to adult. Using a pharmacological approach we found that in SAN true pacemaker cells ivabradine reduces the DDR and the cycle length significantly stronger in E12.5 than in newborn and adult mice, whereas the effects of Ni 2+ and nifedipine were significantly stronger in adult mice. Computer simulations further suggested that the density of the hyperpolarization-activated pacemaker сurrent (I f ) decreased during development, whereas transmembrane and intracellular Ca 2+ flows increased., Conclusions: The ontogenetic decrease in I K1 density from E12.5 to adult leads to depolarization of MDP to the voltage range in which calcium currents are activated, thereby shifting the balance from the "membrane-clock" to the "calcium-clock.", (© 2024 American Association for Anatomy.)

With the rapid development of wireless communication technologies and the miniaturization trend in the electronics industry, the reduction of electromagnetic interference has become an important issue. To solve this problem, a lot of attention has been focused on polymer composites with combined functional fillers. In this paper, we report a method for creating an acrylonitrile butadiene styrene (ABS) plastic composite with a low amount of conductive carbon and magnetic fillers preparation. Also, we investigate the mechanical, thermophysical, and electrodynamic characteristics of the resulting composites. Increasing the combined filler amount in the ABS composite from 1 to 5 wt % leads to a composite conductivity growth of almost 50 times. It is necessary to underline the temperature decrease of 5 wt % mass loss and, accordingly, the composite heat resistance reduction with an increase in the combined filler from 1 to 5 wt %, while the thermal conductivity remains almost constant. It was established that electrodynamic and physical-mechanical characteristics depend on the agglomeration of fillers. This work is expected to reveal the potential of combining commercially available fillers to construct effective materials with good electromagnetic interference (EMI) protection using mass production methods (extrusion and injection molding)., Competing Interests: The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

Background: The distinction between a pre-existing primary headache and a secondary headache at the onset of a disorder is important and has not been taken into account in the International Classification of Headache Disorders-3. This study aimed to improve the general diagnostic criteria for secondary headaches using results of our previous studies., Materials and Methods: We analyzed characteristics of headaches including their changes in intensity, duration, frequency, localization and side, development of new accompanying symptoms, and therapeutic response at the onset of transient ischemic attacks (TIA) (n = 120, mean age 56.1, 55% females) and ischemic stroke (n = 550, mean age 63.1, 56% females) compared to the control group (n = 192, mean age 58.7, 64% females)., Results: Headache of a new type occurred in 8.4% of ischemic stroke patients and 5% of TIA patients on the day of admission but did not occur at all in the control group. Pre-existing headache with a change of at least one characteristic occurred significantly more often in stroke (5.4%) and TIA (7.5%) than in the control group (1%) (p = 0.01 and p = 0.003 respectively)., Conclusion: The presence of a new type of headache and a pre-existing headache with altered characteristics in close temporal relation to a disorder indicates causality. Based on these data we propose revised general diagnostic criteria for secondary headaches., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Migrainous infarction (MI) is a rare disorder. The precise diagnostic criteria for this diagnosis have been available in the International Classification of Headache Disorders (ICHD) since 1988, but many cases do not fulfil these criteria. This paper describes a good example of MI and analyzes previously published case reports. We report a very special case of MI in an 18-year-old woman who had a recurrent episode of migraine with a similar aura with numbness of the right arm and speech disturbances which had an unusually long duration (>120 min). On admission to the headache centre "Europe-Asia", she complained of slowness of speech and problems with choice of words. An MRI showed acute lacunar infarcts in the left parietal subcortical area. Ischemic infarcts were localized in a relevant area on the left side and the aura symptoms were right-sided. The patient, therefore, fulfilled the ICHD-3 diagnostic criteria for "Migrainous infarction". An analysis of 35 previously published articles with case reports about MI showed that 22 did not meet the diagnostic criteria of the ICHD for migrainous infarction. Using all this, we developed diagnostic recommendations for migrainous infarction which can help to improve the quality of diagnosis when used together with the diagnostic criteria of the ICHD for migrainous infarction.

This work aims at studying Raman spectroscopy in combination with chemometrics as an alternative fast noninvasive method to detect chronic heart failure (CHF) cases. Optical analysis is focused on the changes in the spectral features associated with the biochemical composition changes of skin tissues. A portable spectroscopy setup with the 785 nm excitation wavelength was used to record skin Raman features. In this in vivo study, 127 patients and 57 healthy volunteers were involved in measuring skin spectral features by Raman spectroscopy. The spectral data were analyzed with a projection on the latent structures and discriminant analysis. 202 skin spectra of patients with CHF and 90 skin spectra of healthy volunteers were classified with 0.888 ROC AUC for the 10-fold cross validated algorithm. To identify CHF cases, the performance of the proposed classifier was verified by means of a new test set that is equal to 0.917 ROC AUC., (© 2023 Wiley-VCH GmbH.)

Background: It is poorly described how often headache attributed to stroke continues for more than 3 months, i.e. fulfils the criteria for persistent headache attributed to ischemic stroke. Our aims were: 1) to determine the incidence of persistent headache attributed to past first-ever ischemic stroke (International headache society categories 6.1.1.2); 2) to describe their characteristics and acute treatment; 3) to analyse the prevalence of medication overuse headache in patients with persistent headache after stroke; 4) to evaluate factors associated with the development of persistent headache after stroke., Methods: The study population consisted of 550 patients (mean age 63.1, 54% males) with first-ever ischemic stroke, among them 529 patients were followed up at least three months after stroke. Standardized semi-structured interview forms were used to evaluate these headaches during professional face-to-face interviews at stroke onset and telephone interviews at 3 months., Results: At three months, 61 patients (30 women and 31 men, the mean age 60.0) of 529 (11.5%) follow-up patients had a headache after stroke: 34 had a new type of headache, 21 had a headache with altered characteristics and 6 patients had a headache without any changes. Therefore 55 (10.4%) patients had a persistent headache attributed to ischemic stroke. Their clinical features included: less severity of accompanying symptoms, slowly decreasing frequency and development of medication overuse headache in one-third of the patients. The following factors were associated with these headaches: lack of sleep (29.1%, p = 0.009; OR 2.3; 95% CI 1.2-4.3), infarct in cerebellum (18.2%, p = 0.003; OR 3.0; 95% CI 1.4-6.6), stroke of undetermined etiology (50.9%, p = 0.003; OR 2.3; 95% CI 1.3-4.1), less than 8 points by NIHSS score (90.9%, p = 0.007; OR 3.4; 95% CI 1.4-8.6) and low prevalence of large-artery atherosclerosis (12.7%, p = 0.006; OR 0.3; 95% CI 0.2-0.80)., Conclusion: Persistent headache attributed to ischemic stroke is not rare and frequently leads to medication overuse. The problem is often neglected because of other serious consequences of stroke but actually, it has a considerable impact on quality of life. It should be a focus of interest in the follow-up of stroke patients., (© 2022. The Author(s).)

Background: Defining the relationship between a headache and stroke is essential. The current diagnostic criteria of the ICHD-3 for acute headache attributed to ischemic stroke are based primarily on the opinion of experts rather than on published clinical evidence based on extensive case-control studies in patients with first-ever stroke. Diagnostic criteria for sentinel headache before ischemic stroke do not exist. The present study aimed to develop explicit diagnostic criteria for headache attributed to ischemic stroke and for sentinel headache., Methods: This prospective case-control study included 550 patients (mean age 63.1, 54% males) with first-ever ischemic stroke and 192 control patients (mean age 58.7, 36% males) admitted to the emergency room without any acute neurological deficits or severe disorders. Standardized semi-structured interview forms were used to evaluate past and present headaches during face-to-face interviews by a neurologist on admission to the emergency room in both groups of patients. All headaches were diagnosed according to the ICHD-3. We tabulated the onset of different headaches before a first-ever ischemic stroke and at the time of onset of stroke. We divided them into three groups: a new type of headache, the previous headache with altered characteristics and previous unaltered headaches. The same was done for headaches in control patients within one week before admission to the hospital and at the time of entry. These data were used to create and test diagnostic criteria for acute headache attributed to stroke and sentinel headache., Results: Our previous studies showed that headache at onset of ischemic stroke was present in 82 (14.9%) of 550 patients, and 81 (14.7%) patients had sentinel headache within the last week before a stroke. Only 60% of the headaches at stroke onset fulfilled the diagnostic criteria of ICHD-3. Therefore, we proposed alternative criteria with a sensitivity of 100% and specificity of 97%. Besides, we developed diagnostic criteria for sentinel headache for the first time with a specificity of 98% and a sensitivity of 100%., Conclusions: We suggest alternative diagnostic criteria for acute headache attributed to ischemic stroke and new diagnostic criteria for sentinel headache with high sensitivity and specificity., (© 2022. The Author(s).)

Migraine is one of the leading causes of disability worldwide, especially in women younger than 50 years old. Migraine has three times higher prevalence in women than in men and tends to decrease after the menopausal transition. Migraine has different clinical features in people of different ages. Clinical symptoms and factors associated with migraine can be various in women and men. Women have special types of migraine, such as pure menstrual migraine and menstrually related migraine. Besides, clinical symptoms of migraine can change during pregnancy, postpartum and lactation. Women are significantly more often than men consulting a doctor because of migraine. These features of migraine lead to different treatment and management strategies in females and males of different ages. Migraine therefore is a disorder that demonstrates the necessity of a personalization of healthcare-ensuring the proper treatment for the right patient, at the right time. Considering all the available literature and guidelines, in this chapter several strategies for management of acute and prophylactic treatments of migraine, according to sex and age differences, are discussed. The purpose of this chapter is to provide a useful piece of information improving the treatment and management of migraine., (Copyright © 2022 Elsevier Inc. All rights reserved.)

In this study, we hypothesize that angiogenesis of special hepatic vessels such as sinusoid capillaries or veins is closely associated with increasing production of connective tissue in fibrogenesis. Thirty-six male Wistar rats were induced with hepatitis and cirrhosis of the liver using thioacetamide. The number of sinusoidal capillaries, veins, arteries and the area of connective tissue were counted and determined. Immunohistochemical study was performed on paraffin sections using monoclonal mouse anti-CD31. mRNA expression was determined using qPCR. We found a statistically significant reduction in the number of sinusoidal capillaries (p<0.0001) and an increase in the number of interlobular veins (p<0.0001) in the fibrosis and cirrhosis groups compared to the control group. There are no differences in the number of interlobular arteries (p=0.282) in the three groups. In our analysis, we found that the expression (mRNA) of Fn14 correlated with the number of veins in liver fibrosis (r=0.44, p=0.008). Our data shows that modulation of veins angiogenesis during fibrosis in chronic liver diseases may play an important role in increasing pathological changes of the liver., (© The Author(s).)

Background: There are no previous controlled studies of sentinel headache in ischemic stroke. The purpose of the present study was to evaluate the presence of such headache, its characteristics and possible risk factors as compared to a simultaneous control group., Methods: Eligible patients (n = 550) had first-ever acute ischemic stroke with presence of new infarction on magnetic resonance imaging with diffusion-weighted imaging (n = 469) or on computed tomography (n = 81). As a control group we studied in parallel patients (n = 192) who were admitted to the emergency room without acute neurological deficits or serious neurological or somatic disorders. Consecutive patients with stroke and a simultaneous control group were extensively interviewed soon after admission using validated neurologist conducted semi-structured interview forms. Based on our previous study of sentinel headache in transient ischemic attacks we defined sentinel headache as a new type of headache or a previous kind of headache with altered characteristics (severe intensity, increased frequency, absence of effect of drugs) within seven days before stroke., Results: Among 550 patients with stroke 94 patients (17.1%) had headache during seven days before stroke and 12 (6.2%) controls (p < 0.001; OR 3.9; 95% CI 1.7-5.8). Totally 81 patients (14.7%) had sentinel headache within the last week before stroke and one control. Attacks of arrythmia during seven days before stroke were significantly associated with sentinel headache (p = 0.04, OR 2.3; 95% CI 1.1-4.8)., Conclusions: A new type of headache and a previous kind of headache with altered characteristics during one week before stroke are significantly more prevalent than in controls. These headaches represent sentinel headaches. Sudden onset of such headaches should alarm about stroke.

A tritrophic model of Lotka-Volterra type was developed to describe the dynamics of a unisexual-bisexual complex in fish. The model assumes two genetically isolated forms, bisexual (diploid) and unisexual (triploid), competing for a common resource. The efficiency of food conversion into offspring for the unisexual form is dependent on the availability of the diploid males. By means of isoplane analysis the conditions of a non-trivial equilibrium existence are determined. These conditions imply that the unisexual form should be more fit than the bisexual one in terms of lesser mortality and/or more efficient resource utilization. During field work in the summer of 2001, a unisexual-bisexual complex of spined loach, Cobitis taenia, was found in the Sura River (Mordovia). Analysis of demographic and tropho-dynamic parameters of diploid and triploid forms in this complex suggests that the triploid form, though it does not have the presumed advantage in population fecundity, does have an advantage in survival and consumption rate. The overall ratio between population parameters of the two loach forms indicates that the theoretical condition derived from the model equations is met. Thus, ecological traits of the unisexual and the bisexual forms of spined loach make it possible for them to coexist even under conditions of fully overlapping niches.