Publications by authors named "Svetlana Belova"

During skeletal muscle unloading, phosphoinositide 3-kinase (PI3K), and especially PI3K gamma (PI3Kγ), can be activated by changes in membrane potential. Activated IP3 can increase the ability of Ca to enter the nucleus through IP3 receptors. This may contribute to the activation of transcription factors that initiate muscle atrophy processes.

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A morphologically conspicuous microbial association was detected in a bioreactor running in a continuous mode with methanotrophic bacteria of the genus Methylococcus and natural gas as a growth substrate. The association consisted of spherical Methylococcus cells colonized by elongated rods, which produced rosette-like aggregates and inhibited the cultivation process. An isolate of these bacteria, strain S20, was obtained and identified as belonging to the alphaproteobacterial family Ancalomicrobiaceae but displaying only a distant relationship (93.

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Background: Myopia is a growing healthcare concern worldwide. Increasing evidence suggests that sleep and circadian rhythms may be associated with myopia. Furthermore, the risk factors of myopia have not been studied in the Estonian population to date.

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Transmetalation of the bis{triethylantimony(V)}-capped iron(II) tris-α-dioximate with -butylboronic acid afforded the mixed antimony, boron cross-linked clathrochelate with single reactive antimony(V)-based apical fragment. This macrobicyclic precursor easily underwent the transmetalation reactions with germanium and titanium(IV) alkoxides to give the rod-like and angular FeM-trinuclear bis-clathrochelates. Those of the aforementioned diantimony(V)-capped complex with 3- and 4-carboxyphenylboronic acids afforded the monoboron-capped iron(II) semiclathrochelates, undergoing a double-cyclization (macrobicyclization) with germanium- and titanium(IV)-based capping agents.

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A series of monocapped cobalt(II) tris-pyrazoloximates was obtained through the template condensation of the corresponding pyrazoloxime, phenylboronic acid and a suitable cobalt(II) halogenide. Comparing 3-acetylpyrazoloxime its methine-containing homolog, the former produced cobalt(II) clathrochelates in substantially higher yields due to the electron donating effect of the methyl substituent, increasing the N-donor ability of its oxime group. Their less N-donor analog with the electron acceptor trifluoromethyl group did not form cobalt(II) complexes of this type.

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The current study aimed to investigate the hypothesis that purinergic receptors P2Y1 and P2Y2 play a regulatory role in gene expression in unloaded muscle. ATP is released from cells through pannexin channels, and it interacts with P2Y1 and P2Y2 receptors, leading to the activation of markers of protein catabolism and a reduction in protein synthesis. To test this hypothesis thirty-two rats were randomly divided into four groups (8 per group): a non-treated control group (C), a group subjected to three days of hindlimb unloading with a placebo (HS), a group subjected to three days of hindlimb unloading treated with a P2Y1 receptor inhibitor, MRS2179 (HSM), and a group subjected to three days of hindlimb unloading treated with a P2Y2 receptor inhibitor, AR-C 118925XX (HSA).

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The scavenging of atmospheric trace gases has been recognized as one of the lifestyle-defining capabilities of microorganisms in terrestrial polar ecosystems. Several metagenome-assembled genomes of as-yet-uncultivated methanotrophic bacteria, which consume atmospheric CH in these ecosystems, have been retrieved in cultivation-independent studies. In this study, we isolated and characterized a representative of these methanotrophs, strain D3K7, from a subarctic soil of northern Russia.

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Skeletal muscle abnormalities and atrophy during unloading are accompanied by the accumulation of excess calcium in the sarcoplasm. We hypothesized that calcium accumulation may occur, among other mechanisms, due to the inhibition of sarco/endoplasmic reticulum Ca-ATPase (SERCA) activity. Consequently, the use of the SERCA activator will reduce the level of calcium in the sarcoplasm and prevent the negative consequences of muscle unloading.

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Currently, no ideal treatment exists to combat skeletal muscle disuse-induced atrophy and loss of strength. Because the activity of AMP-activated protein kinase (AMPK) in rat soleus muscle is suppressed at the early stages of disuse, we hypothesized that pre-treatment of rats with metformin (an AMPK activator) would exert beneficial effects on skeletal muscle during disuse. Muscle disuse was performed via hindlimb suspension (HS).

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The principal mechanism underlying the reduced rate of protein synthesis in atrophied skeletal muscle is largely unknown. Eukaryotic elongation factor 2 kinase (eEF2k) impairs the ability of eukaryotic translation elongation factor 2 (eEF2) to bind to the ribosome via T56 phosphorylation. Perturbations in the eEF2k/eEF2 pathway during various stages of disuse muscle atrophy have been investigated utilizing a rat hind limb suspension (HS) model.

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Disuse muscle atrophy is usually accompanied by changes in skeletal muscle structure, signaling, and contractile potential. Different models of muscle unloading can provide valuable information, but the protocols of experiments with complete immobilization are not physiologically representative of a sedentary lifestyle, which is highly prevalent among humans now. In the current study, we investigated the potential effects of restricted activity on the mechanical characteristics of rat postural (soleus) and locomotor (extensor digitorum longus, EDL) muscles.

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The title cobalt(II) pseudoclathrochelate complexes possess an intermediate trigonal prismatic-trigonal antiprismatic geometry. As follows from PPMS data, they exhibit an SMM behaviour with Orbach relaxation barriers of approximately 90 K. Paramagnetic NMR experiments confirmed a persistence of these magnetic characteristics in solution.

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The genus Methylomonas accommodates strictly aerobic, obligate methanotrophs, with their sole carbon and energy sources restricted to methane and methanol. These bacteria inhabit oxic-anoxic interfaces of various freshwater habitats and have attracted considerable attention as potential producers of a single-cell protein. Here, we characterize two fast-growing representatives of this genus, strains 12 and MP1, which are phylogenetically distinct from the currently described Methylomonas species (94.

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Didecyldimethylammonium chloride (DDAC) and polyhexamethylene guanidine (PHMG) exhibit high antimicrobial activity and are widely used as biocidal agents in chemical toilet additives for the management of fecal sludge (FS). Disposal of such biocide-treated FS to a wastewater treatment plant (WWTP) is a major environmental problem. It is possible to reduce environmental damage through the use of biocidal agents, which easily decompose after performing their main biocidal functions.

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Muscle unloading leads to signaling alterations that cause muscle atrophy and weakness. The cellular energy sensor AMPK can regulate myofiber-type shift, calcium-dependent signaling and ubiquitin-proteasome system markers. We hypothesized that the prevention of p-AMPK downregulation during the first week of muscle unloading would impede atrophy development and the slow-to-fast shift of soleus muscle fibers, and the aim of the study was to test this hypothesis.

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SBC82 is a recently described representative of the phylum from lichen-covered tundra soil. Cells of this bacterium occur within unusual saccular chambers, with the chamber envelope formed by tightly packed fibrils. These extracellular structures were most pronounced in old cultures of strain SBC82 and were organized in cluster-like aggregates.

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Article Synopsis
  • The study investigated how metformin affects calcium-dependent signaling, protein synthesis markers, and E3 ubiquitin ligase expression during muscle unloading in male Wistar rats.
  • Results showed that hindlimb suspension decreased p-AMPK and increased ATP levels, while metformin treatment reversed these changes and affected various signaling pathways.
  • Additionally, metformin reduced the expression of markers related to protein breakdown (MuRF1 and MAFbx) but did not impact the autophagic pathway indicator (ULK-1).
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Unlabelled: Skeletal muscle unloading leads to the decreased electrical activity and decline of muscle tone.

Aims: Current study evaluated the effect of muscle tone preservation achieved by tetanus toxin (TeNT) treatment on signaling pathways regulating atrophic processes during unloading.

Main Methods: Four groups of rats were used: non-treated control (C), control rats with TeNT administration (CT), 7 days of unloading/hindlimb suspension with placebo (HS), and 7 days of unloading with TeNT administration (HST).

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Hybrid metallo(IV)phthalocyaninate-capped tris-dioximate iron(II) complexes (termed as "phthalocyaninatoclathrochelates") with non-equivalent apical fragments and functionalized with one terminal reactive vinyl group were prepared for the first time using three different synthetic approaches: (i) transmetallation (capping group exchange) of the appropriate labile boron,antimony-capped cage precursors, (ii) capping of the initially isolated reactive semiclathrochelate intermediate, and (iii) direct one-pot template condensation of their ligand synthons on the iron(II) ion as a matrix. The obtained polytopic cage complexes were characterized using elemental analysis, H NMR, MALDI-TOF MS and UV-vis spectra, and the single-crystal X-ray diffraction experiments. One of the obtained vinyl-terminated iron(II) phthalocyaninatoclathrochelates and its semiclathrochelate precursor were tested as monomers in a copolymerization reaction with styrene as the main component.

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The bacterial genus , which comprises aerobic thermotolerant methanotrophic cocci, was described half-a-century ago. Over the years, a member of this genus, Bath, has become a major model organism to study genomic and metabolic basis of obligate methanotrophy. High biotechnological potential of fast-growing species, mainly as a promising source of feed protein, has also been recognized.

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Skeletal muscle unloading results in atrophy. We hypothesized that pannexin 1 ATP-permeable channel (PANX1) is involved in the response of muscle to unloading. We tested this hypothesis by blocking PANX1, which regulates efflux of ATP from the cytoplasm.

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Article Synopsis
  • Research shows that plantar mechanical stimulation (PMS) can increase neuromuscular activity in lower limb muscles and reduce muscle atrophy caused by unloading, such as during hindlimb suspension in rats.
  • * In a study involving a 7-day hindlimb suspension, while PMS did not prevent the overall loss of soleus muscle mass, it was effective in preventing the reduction of slow-twitch fiber cross-sectional area and maintained protein synthesis.
  • * The effects of PMS on anabolic signaling pathways were linked to nitric oxide (NO) activity, suggesting that PMS can partially protect against muscle atrophy during periods of inactivity.
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The in situ spectroelectrochemical cyclic voltammetric studies of the antimony-monocapped nickel(II) and iron(II) tris-pyridineoximates with a labile triethylantimony cross-linking group and Zr(IV)/Hf(IV) phthalocyaninate complexes were performed in order to understand the nature of the redox events in the molecules of heterodinuclear zirconium(IV) and hafnium(IV) phthalocyaninate-capped derivatives. Electronic structures of their 1e-oxidized and 1e-electron-reduced forms were experimentally studied by electron paramagnetic resonance (EPR) spectroscopy and UV-vis-near-IR spectroelectrochemical experiments and supported by density functional theory (DFT) calculations. The investigated hybrid molecular systems that combine a transition metal (pseudo)clathrochelate and a Zr/Hf-phthalocyaninate moiety exhibit quite rich redox activity both in the cathodic and in the anodic region.

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Upland soils of tundra function as a constant sink for atmospheric CH but the identity of methane oxidizers in these soils remains poorly understood. Methane uptake rates of -0.4 to -0.

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