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The calcium-sensing receptor (CaSR) gene encodes a cell membrane G protein-coupled receptor (GPCR) which has a key role in maintaining the extracellular Ca2+ homeostasis. We aimed at correcting the compound heterozygous mutation in the 6th [c.1656delA, p.I554SfsX73] and 7th [c.2217 T > A, p.C739X] exons of the CASR gene which the original patient-derived iPSC line had. The mutation is associated with neonatal severe primary hyperparathyroidism of the patient. We generated and characterized a CRISP/Cas9-edited hiPSC line with the restored sequence in the sixth exon of the CASR gene, bearing only heterozygous mutation in the 7th exon. The results showed that the new genetically modified cell line has karyotype without abnormalities, typical hiPSCs morphology, characteristic expression of pluripotency markers, and ability to develop into three germ layers, and differentiates in chondrogenic, adipogenic, osteogenic directions. This new cell line will complement the existing pool of CaSR-mutated cell lines, a valuable resource for in-depth understanding of neonatal severe primary hyperparathyroidism. This will allow further exploration of the application of pharmacological drugs in the context of personalized medicine to correct Ca-homeostasis disorders. [ABSTRACT FROM AUTHOR]

Tactile imagery remains a relatively understudied phenomenon of mental imagery research. However, this technique holds promise as an effective tool for sensorimotor rehabilitation following stroke and spinal cord injuries alongside motor imagery. In this study, conducted with 22 healthy volunteers, the authors investigated the source localization of μ-rhythm event-related desynchronization (ERD) using multichannel electroencephalogram recordings and subsequent inverse problem solution with the sLORETA. All participants exhibited ERD during tactile imagery task and under vibrotactile stimulation. It was demonstrated that μ-rhythm ERD during both vibrotactile stimulation and tactile imagery was localized in the sensorimotor areas of the contralateral hemisphere. Within the source space, ERD in the postcentral gyrus was significantly stronger compared to the precentral gyrus. These findings indicate that tactile imagery, akin to the perception of real tactile stimuli, leads to prominent activation of sensorimotor cortical areas, consistent with the general understanding of the shared neural substrate during mental imagery and perception. [ABSTRACT FROM AUTHOR]

Neuropathic pain results from nerve injury and possesses a distinct disease mechanism compared to other types of chronic pain. Since it is associated with damage to the nervous tissue, studying lipidome alterations related to neuropathic pain could constitute an important layer in the understanding of this condition. However, pain-related molecular changes remain poorly understood, particularly in the brain. Here, we assessed the lipid abundances in two brain regions, namely, insular cortex (IC) and somatosensory cortex (S1) in rats that were subject to sciatic nerve constriction (SNC) injury—a common animal model of neuropathic pain, and compared them to the lipidome of control rats that underwent a sham surgery. We found a significant increase of lipids containing particular fatty acids (22:5, 20:3) in SNC rats compared to controls. On the level of lipid classes, we detected increased levels of lysophosphatidylethanolamines (LPE) and decreased levels of phosphatidylethanolamines (PE). While lipid alterations in SNC correlated positively between regions, the amplitude and significance of the lipid differences was larger in IC. In parallel, we analysed blood plasma lipids of the same rats and compared alterations between the two types of tissue. The blood plasma lipidome mirrored differences found for the brain, in particular those related to the lipids' fatty acid composition. Taken together, these results indicate alterations in fatty acid metabolism as a possible marker associated with neuropathic pain. [ABSTRACT FROM AUTHOR]

Motor impairment is one of the most prevalent consequences of a stroke, necessitating the implementation of efficacious diagnostic and rehabilitative techniques. An evaluation of alterations in sensorimotor cortical activity during the processes of movement preparation and execution can provide valuable insights into the state of motor circuits following a stroke and the potential for recovery. The objective of the present study was to evaluate the spatiotemporal characteristics of event-related desynchronization (ERD) of sensorimotor EEG rhythms in patients with hemiparesis following a stroke, during movements with the paretic and healthy hands. A total of 19 patients with hemiparesis following a stroke participated in the study. An EEG was recorded while the subject performed a visual-motor task. The analysis focused on the event-related desynchronization in the alpha (6–15 Hz) and beta (15–30 Hz) bands. An asymmetry in the ERD was observed, with a predominant response in the intact hemisphere, regardless of the hand performing the movement. The magnitude of the ERD in the affected hemisphere demonstrated a correlation with the Fugl-Meyer score. Furthermore, a notable correlation was identified between the magnitude of beta-ERD in the affected hemisphere during movements of the healthy limb and the degree of motor function recovery. The results demonstrate the utility of ERD pattern assessment for diagnosing the state of sensorimotor networks after stroke. The detection of a correlation between the magnitude of ERD during movements of the healthy arm and the assessment of sensorimotor functions of the patient expands the possibilities of using EEG to assess patients even with complete absence of movements in the paretic limb. [ABSTRACT FROM AUTHOR]

Silicon nitride membranes were experimentally obtained as substrates for biological samples, which are examined using a microscope with an operating wavelength of 13.8 nm. The free-hanging films obtained have a size of up to 1.5 × 1.5 mm2, which makes it possible to select an area of interest for investigation on the sample on the order of tens to hundreds of microns. The mechanical strength of the membranes satisfies that the samples do not tear the membranes and withstand transportation. The results obtained are an import-substituting technology for the manufacture of Si3N4 membranes. The resulting membranes have a transparency of more than 40% in the range of the "water transparency window" (2.3–4.4 nm) and EUV (13–15 nm). The developed technology will become the basis for creating cuvettes for living biological samples for soft X-ray microscopy studies. [ABSTRACT FROM AUTHOR]

The effect of sequential formation of protonated and deprotonated forms of 2,3,7,13,17,18-hexamethyl-8,12-di-n-butylcorrole in solution on their photophysical characteristics and spectral-luminescent properties was studied. The spectral characteristics of each of the two forms in the ground electronic state were found to be the same when they formed from the free base and from the antipodal form, while the fluorescence spectra of the two forms differed depending on the method of formation. Based on an analysis of spectral shifts in fluorescence spectra and fluorescence quantum yields, it was concluded that the protonated and deprotonated forms of corroles underwent specific interactions in the lower excited singlet S1 state due to the formation of a complex solvation shell. These specific interactions were shown to lead to hysteresis of the fluorescence characteristics of the protonated and deprotonated forms of corroles with their mutual transitions caused by (cyclic) changes in the acid–base equilibrium. [ABSTRACT FROM AUTHOR]

It is proposed to use "liquid glasses" of various compositions as substrates for space-based X-ray optical elements. One of the main requirements for such materials is the smallest weight and the possibility of surface treatment. Special requirements are imposed on the surface roughness, which should be less than 1 nm, and the shape accuracy should be at the level of a few nanometers. It is proposed to use a class of compounds based on alkali-metal silicates or strong organic bases as a material that makes it possible to form the required shape and surface roughness, as well as to provide subsequent processing. The effect of smoothing the surface roughness of liquid glass of three different compositions deposited onto chromium and nickel films is studied. The roughness of all surfaces before and after the deposition of structures is measured using an atomic force microscope. The roughness was calculated using the power spectral density function (PSD function). The structures deposited onto the surface were irradiated with accelerated argon ions with an energy of 800 eV. The etching depth and effective roughness were measured. One of the studied compositions shows a satisfactory reduction in the roughness and stability of this effect during ion etching. [ABSTRACT FROM AUTHOR]

5-Methyl-2'-deoxycytidine (mC) at CpG sites plays a key role in the epigenetic gene regulation, cell differentiation, and carcinogenesis. Despite the importance of mC for normal cell function, CpG dinucleotides are known as mutagenesis hotspots. Deamination of mC yields T, causing C→T transitions. However, several recent studies demonstrated the effect of epigenetic modifications of C on the fidelity and efficiency of DNA polymerases and excision repair enzymes. The review summarizes the available data that indicate the existence of deamination-independent mechanisms of mutagenesis at CpG sites. [ABSTRACT FROM AUTHOR]

The π-conjugation pathways were identified and the degrees of aromaticity for NH-tautomers of corrole free bases were determined by quantum chemistry methods and absorption spectroscopy. The macrocycle skeletal atoms participated differently in the formation of the π-conjugation pathway. It was supposed that conjugation pathways consisting of 18 π-electrons were dominant. At the same time, each of two NH-tautomers possessed its own distinct π-conjugation pathway, which caused their degrees of aromaticity to differ. It was shown that the peripheral substitution architecture of the macrocycle influenced the degree of aromaticity. A method for controlling the equilibrium between the two NH-tautomers that consisted of designing the electron-density distribution in the macrocycle that was characteristic of one of the tautomers was proposed and proved experimentally. [ABSTRACT FROM AUTHOR]

Naphtha reforming is one of the most important industrial processes in refineries. The products include aromatic hydrocarbons such as benzene, toluene, and xylenes, which are frillier used as high octane additives to gasoline. To increase the efficiency of the process, it is necessary to develop a new method of naphtha reforming. In this work, we have proposed a mathematical model of catalytic refining of low-octane gasoline fracdons into high-octane fractions. The model is based on kinetic equations, established for commercial gasoline reforming in the presence of the platinum-rhenium catalyst on a γ-Al2O3 carrier in the industrial-scale conditions. The equation: describe the dependence of the content of paraffinic, naphthenic, and aromatic hydrocarbon fractions on the process parameters, including volumetric rate and the reaction temperature. The mathematical model had been validated by comparing calculated results with the industrial data obtained from the commercial naphtha reforming production. [ABSTRACT FROM AUTHOR]

5-Methyl-2'-deoxycytidine (mC) and the product of its controlled oxidation, 5-hydroxymethyl-2'-cytidine (hmC), play a key role in the epigenetic regulation of gene expression, the cell differentiation, and the carcinogenesis. Due to spontaneious deamination, genomic CpG sites containing mC and hmC serve as mutagenesis hotspots. In addition, error-prone translesion and reparative DNA polymerases may serve as additional source of mutations in the lesion-containing regions with CpG sites. In the present work, we performed in vitro analysis of the accuracy of nucleotide incorporation opposite to mC and hmC by human DNA polymerases Polβ, Polλ, Polη, Polι, Polκ and primase polymerase PrimPol. The results of the study show a high accuracy of copying mC and hmC by the reparative DNA polymerases Polβ and Polλ, while Polη, Polι, Polκ, and PrimPol copied mC and hmC with less accuracy evident by incorporation of dAMP and dTMP. The same spectrum of error-prone dNMP incorporation was also noted at sites with unmodified cytosines. [ABSTRACT FROM AUTHOR]

The molecular structures and spectral and luminescent properties of 2,3,7,13,17,18-hexamethyl-8,12-di-nbutylcorrole and 7,13-dimethyl-8,12-di-n-butylcorrole free bases in solutions at 288–328 K were studied using luminescence and absorption spectroscopy and quantum chemistry. Absorption and fluorescence spectra of the compounds were shown to be superimposed spectra of two NH-tautomers. Individual tautomer spectra were identified. Bands were assigned to specific transitions. NH-tautomer equilibria in the ground S0 and lower excited S1 singlet states were characterized. [ABSTRACT FROM AUTHOR]

We studied the influence of the estrous cycle on the morphology of preovulatory (germinal vesicle, GV) oocytes in mice and their capacity to meiotic maturation in vitro. After standard injections of eCG gonadotropin (PMSG, Follimag) to females at different stages of the estrous cycle, the maximum levels of GV oocytes (26±1/mouse) were isolated from the ovaries of animals injected with the hormone during estrus. The capacity of isolated GV oocytes to meiotic maturation in vitro decreased in the following order: estrus (75.5±2.3%), metestrus (67.9±3.4%), proestrus (57.8±4.4%), and diestrus (50.6±5.6%); the differences between estrus and diestrus/proestrus were significant (p<0.05). After eCG injections during estrus, GV oocytes differed from other oocytes by lesser total diameter, lesser diameter of cytoplasm, lesser thickness of zona pellucida, and moderately dilated perivitelline space. These signs reflected higher competence of the "estrous" GV oocytes for meiotic maturation in vitro. Hormone stimulation of females with eCG, with consideration for the stage of the estrous cycle, seems to be an effective method for improving the quality of GV oocytes isolated from mouse ovaries. [ABSTRACT FROM AUTHOR]

The effects of two types of catalysts and the catalyst/feedstock ratio on the fractional composition and basic physical properties of the bio-oil were studied. Chlorella microalgae biomass was used as the feedstock. Zeolite ZSM-5 in the H-form and ZrO2/Al2O3 in the sulfate-form were used as the catalysts. Increasing the catalyst load was shown to have positive effects on the contents of gasoline and diesel fractions in the bio-oil, to reduce significantly its density and viscosity, and to lower slightly the total sulfur content. [ABSTRACT FROM AUTHOR]

The mutagenic effect of accelerated heavy charged particles on the Chinese hamster V79 cell line is studied. The induction of HPRT mutations in irradiated cells for a long expression time (up to 45 days) after exposure to radiation with different LET are analyzed. The maximum yield of mutant clones is observed at different expression times, depending on the characteristics of ionizing radiation; in this case, the position of the maximum is shifted toward later time intervals with increasing LET of radiation. [ABSTRACT FROM AUTHOR]

Diffusion permeability and electrical conductivity have been studied for bilayer perfluorinated MF-4SC membranes modified with halloysite nanotubes (HNTs) containing noble metal nanoparticles (NPs) deposited onto their surface. It has been found that the diffusion permeability of the bilayer membranes depends on their orientation with respect to an electrolyte flow: the diffusion flux is higher when the modified side of the membrane faces a flow. The study of the electrodiffusion characteristics of HNT-modified bilayer perfluorinated membranes has resulted in the factors being revealed that have the strongest influence on the development of the asymmetry of their current–voltage curves. It has been found that, to obtain a membrane with a fortiori asymmetric properties, it is necessary to synthesize a material the layers of which differ from each other in only one component—either HNTs or metal NPs. The efficiency of the modified membranes as polymer electrolytes for hydrogen-air fuel cells has been determined, and it has been shown that the modification with HNTs reduces the specific power of a fuel cell, while the presence of platinum NPs on a nanotube surface increases this parameter. The reason for the increase in the specific power is the catalytic activity of platinum NPs in the interaction between oxygen and hydrogen in the membrane bulk, which leads to the self-humidifying of the membrane and a decrease in its ohmic resistance. [ABSTRACT FROM AUTHOR]

Only a limited number of tools are available to study cytosine methylation in DNA. One of the representatives of the recently discovered methyl-dependent DNA endonucleases is an enzyme GlaI. It is of great interest for determining the methylation status of eukaryotic genomic DNA due to its ability to cleave only methylated DNA. However, the ability of the GlaI endonuclease to recognize oxidized derivatives of 5-methylcytosine (mC), in particular another epigenetic base, 5-hydroxymethylcytosine (hmC), has not yet been characterized. It is not possible to fully use the potential of GlaI in the analysis of methylation due to the notable occurrence of the latter in the DNA of mammals. In this study, the efficiency of cleavage of DNA substrates with various combinations of mC and hmC by methyl-dependent DNA-endonuclease GlaI was compared; the kinetic parameters of cleavage reactions for fully methylated and fully hydroxymethylated recognition site were determined. It was shown that in most cases GlaI recognized substrates containing mC better than substrates containing hmC in the same positions. The most effective hydrolysis of substrates containing modifications in the sequence 5'-GCGC-3'/3'-CGCG-5' required the presence of hmC not only in the central but also in the edge positions in both DNA chains as in the case of mC. [ABSTRACT FROM AUTHOR]

The study examined maturation of preovulatory germinal vesicles oocytes (GV oocytes) induced by gonadotropic hormone PMSG in the inbred C57Bl/6J mice (viewed as a gold standard for diverse biomedical studies) as well as in the first generation hybrid C57Bl/6J×СВА/lac and СВА/lac×C57Bl/6J mice at various ages. The most effective donors of GV oocytes were СВА/lac×C57Bl/6J mice (F1 hybrids) yielding 25±2 oocyte/mouse. In contrast, a significantly smaller number of GV oocytes can be isolated from the ovaries of female C57Bl/6J or C57Bl/6J×СВА/lac mice under the same conditions. At this, the greatest number of GV oocytes (42±4) can be retrieved from the ovaries of immature hybrid СВА/lac×C57Bl/6J mice aged 4 weeks. These mice demonstrated the largest share of GV oocytes, which attained MII stage during in vitro culturing. The data conclude that F1 hybrid СВА/lac×C57Bl/6J mice can be viewed as a handy experimental source yielding a large number of GV oocytes capable of meiotic maturation in a culture. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the function of the utriculus and sacculus and their central connections by ocular and cervical vestibular-evoked myogenic potentials (oVEMPs and cVEMPs), and the function of high-frequency VOR of the semicircular canals by video head impulse test (vHIT) in patients with panic disorder (PD). Methods: Forty-eight patients with PD (21 with agoraphobia) and 20 sex- and age-matched healthy controls took part in the investigation. The vestibulo-ocular reflex (VOR) gains and latencies and peak-to-peak amplitudes of sound-induced VEMPs were measured and compared with those of healthy controls. Results: Any statistical differences in the parameters of cVEMP and oVEMP responses between both PD patients groups and between patients and healthy controls were not observed. Also, significant differences between VOR in patients and healthy controls were not found. The VOR gain, bilaterally in the three semicircular canals was within normal limits (0.8–1.2) for 67%, and higher for 33% of the patients with PD. Overt and covert saccades were not observed. The relationship between higher VOR gains and the increase of postural instability when a sensory conflict exists (standing on foam pad with eyes closed) for patients with PD was established. Conclusion: The VEMPs and vHIT tests demonstrated that there is no evidence of hypofunction of the semicircular canals in the high-frequency spectrum of VOR functioning. Nor are there any indications of impairment of the otolith system in patients with PD, regardless of their subjective vestibular sensations. The findings of the current study confirm the proposed link between anxiety, panic symptoms and postural instability in PD patients. [ABSTRACT FROM AUTHOR]

Purpose: The third most frequently diagnosed cancer in Europe in 2018 was lung cancer; it is also the leading cause of cancer death in Europe. We studied patient and tumor characteristics, and patterns of healthcare provision explaining regional variability in lung cancer survival in southern Spain. Methods: A population-based cohort study included all 1196 incident first invasive primary lung cancer (C33–C34 according to ICD-10) cases diagnosed between 2010 and 2011 with follow-up until April 2015. Data were drawn from local population-based cancer registries and patients' hospital medical records from all public and private hospitals from two regions in southern Spain. Results: There was evidence of regional differences in lung cancer late diagnosis (58% stage IV in Granada vs. 65% in Huelva, p value < 0.001). Among patients with stage I, only 67% received surgery compared with 0.6% of patients with stage IV. Patients treated with a combination of radiotherapy, chemotherapy, and surgery had a 2-year mortality risk reduction of 94% compared with patients who did not receive any treatment (excess mortality risk 0.06; 95% CI 0.02–0.16). Geographical differences in survival were observed between the two regions: 35% vs. 26% at 1-year since diagnosis. Conclusions: The observed geographic differences in survival between regions are due in part to the late cancer diagnosis which determines the use of less effective therapeutic options. Results from our study justify the need for promoting lung cancer early detection strategies and the harmonization of the best practice in lung cancer management and treatment. [ABSTRACT FROM AUTHOR]

Abstract: Nanocellulose is a natural nanomaterial produced by the mechanical disintegration or acid hydrolysis of cellulose fibers. In recent years, nanocellulose has been extensively studied worldwide as a natural biodegradable modifier of synthetic polymer materials. The review describes the use of nanocellulose to improve the transport properties of ultrafiltration membranes used for the purification of aqueous media. [ABSTRACT FROM AUTHOR]

The dependence of the colloidal stability, effective viscosity, penetration, and yield stress of low-temperature polymeric greases on the composition and characteristics of the dispersion medium was investigated. Various types of low-viscosity oil with known fractional and group composition were used as base oils. The effect of the concentration of the two-component thickener of high- or low-molecular polypropylene and the proportions of its components on the main physicochemical characteristics of the polymer greases was determined. The dependence of the structure and properties of the polymer greases on the concentration of lithium stearate was established. [ABSTRACT FROM AUTHOR]

Complex tasks require the learning and integration of multiple cognitive, sensory, and psychomotor skills for correct execution. Driving-related skills are developed step by step through the increase of mileage driven and the accumulation of practice in different traffic situations. The acquisition of these skills should be reflected in the brain structure. However, no previous studies have explored brain structural variations associated with driving experience. The aim of the present study was to investigate whether driving frequency, defined as average annual driving mileage, is related to neuroanatomical variations in gray matter (GM) volume and white matter (WM) integrity using voxel-based morphometry (VBM) and DTI-based fractional anisotropy (FA), respectively. We recruited 83 drivers with variable range of annual driving mileage and controlled for age, sex, handedness, IQ, time since the acquisition of driving license, use of motorcycles/mopeds and bicycles, perceived driving skills, and subjective probability of having an accident. Our results showed variations in white matter FA as a function of mileage driven. Driving experience was related to a significant increase of FA in parts of the right hemisphere superior and inferior longitudinal fasciculus, anterior thalamic radiation, forceps majors, inferior fronto-occipital fasciculus, and corticospinal tract. No significant differences were observed in gray matter volumes. FA variations were found in brain regions that have been associated with cognitive, visual, and motor processes necessary for skilled performance in driving. These results suggest that variations in white matter diffusivity can underlie the development of driving skills and safer driving. [ABSTRACT FROM AUTHOR]

Sixty-six isolates of basidiomycete fungi were screened for the ability to synthesize cellulase. The effect of temperature on cellulase activity was studied for eight basidiomycete strains as perspective producers of ethanol. The temperature optima of enzyme activity ranged between 26 and 32°C. Direct conversion of Na-carboxymethyl cellulose, microcrystalline cellulose and rye straw were studied for seven basidiomycetes strains: Fomitopsis pinicola MT-5.09, F. pinicola MT-5.21, Piptoporus betulinus MT-30.04, Fomes fomentarius MT-4.05, F. fomentarius MT-4.23, Trametes hirsuta MT-24.24, Flammulina velutipes MT-3.03 Maximum ethanol production from Na-carboxymethyl cellulose (1.3 g/dm) was achieved by strain F. velutipes MT-3.03. Strain F. fomentarius MT-4.05 more effectively converted rye straw to ethanol with yield of 1.1 g/dm. [ABSTRACT FROM AUTHOR]

Spectral characteristics (electronic absorption spectra, fluorescence emission spectra, H NMR) of prepared Cu(II) and Zn(II) complexes of 2,7,12,17-tetraphenylporphycene {H(β-Ph)Por}, their thermal stability, and persistence toward acids, as well as electrochemical and electrocatalytic properties have been discussed. It has been found by cyclic voltammetry that the electrocatalytic activity of metalloporphycenes M(β-Ph)Por in the reaction of molecular oxygen reduction is close to that of metalloporphyrins M(ms-Ph)P. Thermal stability and persistence of M(β-Ph)Por in acidic medium are considerably lower than those of porphyrin analogs. Thus, the kinetic stability of copper(II) complex of 2,7,12,17-tetraphenylporphycene in HOAc-HSO medium as compared with Cu(ms-Ph)P is lower by more than an order of magnitude, while its thermal stability is almost 200°С lower, which is caused by sterically unfavorable change in the shape of coordination center of ligand H(β-Ph)Por upon complexation. [ABSTRACT FROM AUTHOR]

Sixty six isolates were screened for ability of bioethanol production; dynamics of product accumulation and substrate utilization were investigated for two selected strains Trametes hirsuta MT-24.24 and Trametes versicolor IT-1. The strains' efficiency was evaluated as bioethanol production by 1 g biomass. Strain T. versicolor IT-1 producing over 33 g/L of the ethanol for 9 d was selected. Direct conversion of Na-carboxymethyl cellulose, microcrystalline cellulose and straw was shown with ethanol yields of 2.1, 1.6 and 1.7 g/L, respectively, for 9 d fermentation time. [ABSTRACT FROM AUTHOR]

Microbial diversity in the sediments of the Kara Sea shelf and the southern Yenisei Bay, differing in pore water mineralization, was studied using massive parallel pyrosequencing according to the 454 (Roche) technology. Members of the same phyla ( Cyanobacteria, Verrucomicrobia, Actinobacteria, Proteobacteria, and Bacteroidetes) predominated in bacterial communities of the sediments, while their ratio and taxonomic composition varied within the phyla and depended on pore water mineralization. Increasing salinity gradient was found to coincide with increased share of the γ- Proteobacteria and decreased abundance of α- and β- Proteobacteria, as well as of the phyla Verrucomicrobia, Chloroflexi, Chlorobi, and Acidobacteria. Archaeal diversity was lower, with Thaumarchaeota predominant in the sediments with high and low mineralization, while Crenarchaeota predominated in moderately mineralized sediments. Microbial communities of the Kara Sea shelf and Yenisei Bay sediments were found to contain the organisms capable of utilization of a broad spectrum of carbon sources, including gaseous and petroleum hydrocarbons. [ABSTRACT FROM AUTHOR]

Pyrosequencing of amplicons V3-V4 of the 16S rRNA gene of 30 samples from the photic layer across the three basins of Lake Baikal has revealed 44 958 sequences of the domain Bacteria. The most representative phylums among all classified sequences in the samples were Actinobacteria, Bacteroidetes, Verrucomicrobia, Proteobacteria, Acidobacteria, and Cyanobacteria. As much as 38.5% of the total number of sequences has been determined to the level of genus. The taxonomic composition of bacterial communities was similar regardless of some differences in the composition and abundance of spring phytoplankton. Closely related or identical sequences of bacteria inhabiting the epilimnion of other lakes worldwide have been discovered for most sequences. This confirms the similarity of microbial communities in freshwater ecosystems. [ABSTRACT FROM AUTHOR]

Porphycene, β-phenyl-substituted analog of tetraphenylporphyrin, and its complexes with Cu(II) and Zn(II) have been prepared. Spectral parameters of the porphycene, its acid-base properties and thermal stability in the solid phase as well as its complexes stability towards dissociation in acidic medium have been studied by means of electronic absorption and NMR spectrometry, mass spectroscopy, thermogravimetry, and quantum chemistry simulation. [ABSTRACT FROM AUTHOR]

The conformational properties of a dansyl amide molecule (CH)N-CН-SONH, which is widely used for fluorescent labeling of compounds, e.g., amino acids or nucleotides and compounds able to form liquid crystals, are studied. It is found that the molecule has six conformers with relative energies 0/0.13, 1.13/1.38, 0.06/0.06, 0.31/0, 2.95/2.70, 0.31/0 (B3LYP/cc-pVTZ and МР2/cc-pVTZ methods respectively). In all conformers the naphthalene core becomes non-planar under the effect of two substituents. The effect of the nature of substituents on the geometric parameters of the conformers is considered. In terms of the NBO analysis a substantial deviation of the S-N bond in the -SONH substituent from orthogonality and also the asymmetrical position of the -N(СH) group with respect to the naphthalene core are explained. The paths and barriers of conformational transformations of the dansyl amideа molecule are determined. The structure of the (CH)N-CH-SONН-X moiety in the crystals is analyzed and the relationship between the relative energy of the conformers of a free molecule and the probability of the occurrence of their structures in the crystals is determined. [ABSTRACT FROM AUTHOR]

High-throughput method of sequencing was applied to determine the complete nucleotide sequence of an araphid pennate diatom Synedra acus subsp. radians from Lake Baikal (East Siberia). The assembled genome has a total length of 98 Mbp, the mean coverage is 33x. Structure-functional annotation of the genome was performed. [ABSTRACT FROM AUTHOR]

A concept for the experimental study of the physical properties of entangled electron spin states in a solid body is proposed. The construction of the experimental setup is developed. New-generation electron spin detectors are created. Test measurements of the electron spin polarization by two simultaneously operating Mott detectors are carried out. It is found that Bell's inequalities are satisfied in the traditional measurement mode (without time coincidences of the pulses). [ABSTRACT FROM AUTHOR]

Among isolates of the eubacteria Brevundimonas bullata, Sphingomonas rhizogenes, Agrobacterium tumefaciens, Bacillus simplex, Acinetobacter johnsonii, Methylobacterium adhaesivum, and Deinococcus aquaticus isolated from the bottom layer on the medium, where the only source of organic matter was hydrolysate from diatoms, the activity of hydrolytic enzymes, such as proteases, β-xylosidase, β-glucosidase, β-galactosidase, chitobiase, and amylase, is revealed. An algicidal effect and degradation of siliceous diatom frustules are recorded in algal-bacterial cultures. These data show that the bottom water layer of Lake Baikal is inhabited by potential participants of silicon cycle, which degrade siliceous valves of diatoms. [ABSTRACT FROM AUTHOR]

The article presents a study that analyzes the sequences obtained by pyrosequencing of genomic DNA from axenic culture. It shows that the genome of the diatom contains a gene encoding an aquaporin-like protein, whose structure differs from the structure of typical aquaporins, aquaglyceroporins, and atypical proteins. The results open new possibilities for studying the aquaporin-like proteins of Chromista.

Problems arising in the statement of principles of quantum physics in the course of general physics related to a proof of Bell's inequalities and experimental verification of their violation are considered. Some erroneous or inexact statements in modern general physics textbooks are criticized. Recommendations on their elimination are given. [ABSTRACT FROM AUTHOR]

The existence of the cluster of duplicated sit silicon transporter genes in the chromosome of the diatom Synedra acus subsp. radians was shown for the first time. Earlier, the localization of sit genes in the same chromosome and cluster formation caused by gene duplication was shown only for the marine raphid pennate diatom P. tricornutum. Only non-clustered sit genes were found in the genomes of other diatoms. It is reasonable to assume that sit tandem ( sit-td) and sit triplet ( sit-tri) genes of S. acus subsp. radians occurred as a result of gene duplication followed by divergence of gene copies. [ABSTRACT FROM AUTHOR]

The article reports on the results of a study designed to detect the silicic acid transport (SIT) protein of the freshwater diatom Synedra acus by immunoblotting in protein extracts and by immunoelectron microscopy in ultrathin sections using antibodies to synthetic peptides. A description of the study design and measurement method is presented. The study provides the primary structure of a fragment of the SIT protein from Synedra acus.

Streptomyces strain 3B constitutively secreted collagenolytic enzymes during the post-exponential growth phase. Purification is described here leading to two collagenases (I and II) with specific activity of 3350 and 3600 U/mg, respectively, the highest activity obtained as yet for any streptomycete collagenase. Analysis of the purified enzymes by the method of zymography revealed that both I and II were homogeneous, with molar mass 116 and 97 kDa, respectively. Both collagenases were identical in their pH (7.5) and temperature optimum (37 °C). The inhibition profile of the enzymes by EDTA and 1,10-phenanthroline confirmed these enzymes to be metalloproteinases. By testing the activity with insoluble collagen, acid soluble collagen, gelatin, casein, elastin and Pz-PLGPR it was established that I and II are very specific for insoluble collagen and gelatin, showing a high activity toward acid soluble collagen and Pz-PLGPR. However, collagenases I and II failed to hydrolyze casein and elastin; they belong to true collagenases and resemble the clostridial enzymes. [ABSTRACT FROM AUTHOR]

Sequenced fragments of genes coding for silicon transporters (SITs) were analyzed for diatoms of evolutionarily distant classes (centricChaetoceros muelleriLemmermann, pennate araphidSynedra acusKützing, pennate raphidPhaeodactylum tricornutumBohlin, and pennateCylindrotheca fusiformisReimann et Lewin with a keeled raphe system). SITs were found to contain a conserved motif, CMLD. Hydropathy profiles showed that the motif CMLD is between two transmembrane domains lacking Lys and Arg, and the domains were consequently assumed to play a role in the formation of a channel mediating silicic acid transport. The motif CMLD proved to be rare. Since Zn2+ is necessary for silica incorporation into diatom cells, a hypothesis was advanced that the motif CMLD acts as a Zn-binding site. Diatom growth suppression was observed in the presence of the alkylating agentN-iodoacetylamidoethyl-1-aminonaphthalene-5-sulfonic acid (AEDANS), which does not penetrate into the cell. Cys of the motif CMLD was assumed to act as a target for AEDANS. Zinc ions inhibited Cys alkylation in the synthetic peptide NCMLDY, testifying to the above hypothesis. [ABSTRACT FROM AUTHOR]

Colorectal cancer is one of the most common neoplastic diseases and one of the leading causes of cancer-related deaths. Elevated β-catenin levels in colorectal cancer result in the binding of β-catenin to LEF-1 and increased transcriptional activation of the CCND1 gene. Overexpression of cyclin D1 is observed in one third of colorectal tumors. CCND1 amplification is the main cause of protein overexpression in numerous human carcinomas. In colorectal cancer, however, no CCND1 amplification has been reported so far. The aim of this study was to determine the frequency of CCND1 amplifications and gains in a large number of colorectal carcinomas, arranged in a tissue microarray, in order to assess their role in colorectal cancer development. The copy number changes, detected by fluorescence in situ hybridization, were predominantly gains (7.6%) and only rarely amplifications (2.5%). In colorectal cancer, the CCND1 copy number increase was neither associated with the tumor phenotype (stage and grade) nor with the tumor localization (colon, rectum or sigmoid colon). In conclusion, even in a small number of colorectal tumors, CCND1 gene amplification is a possible mechanism for the increase in cyclin D1 oncoprotein. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

In the 4th paragraph on page 565, the word "molarities" should be replaced with "molalities." In Fig. 2 on page 566, the y-axis should read "Counts." In the 3rd paragraph on page 566, "mean deviation" should be replaced with "standard deviation." [ABSTRACT FROM AUTHOR]