Publications by authors named "Petrov K"

The decoupled power and energy output of a redox flow battery (RFB) offers a key advantage in long-duration energy storage, crucial for a successful energy transition. Iodide/iodine and hydrogen/water, owing to their fast reaction kinetics, benign nature, and high solubility, provide promising battery chemistry. However, H-I RFBs suffer from low open circuit potentials, iodine crossover, and their multiphase nature.

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The present study investigates the natural ability of Bacillus velezensis R22 to produce 2,3-BD from two inulin-rich substrates - insoluble and soluble chicory flour. After complex optimization of the media content and process parameters by consecutive application of Plackett-Burman design and response surface methodology, the strain R22 was capable of producing 71.2 g/L (95.

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Alzheimer's disease (AD) poses a significant public health issue. Despite the fact that today there are several methods of maintenance therapy, one of the most widely used methods is designed to correct the deficiency of acetylcholine. In the search for new potential inhibitors of cholinesterase enzymes, eight new derivatives of 3-oxo- or 2,3-indolo-triterpenic acid conjugated with amino-quinuclidine bicyclic cores were designed and synthesized.

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The unique fuel characteristics of butanol and the possibility of its microbial production make it one of the most desirable environmentally friendly substitutes for petroleum fuels. However, the highly toxic nature of 1-butanol to the bacterial strains makes it unprofitable for commercial production. By comparison, 2-butanol has similar fuel qualities, and despite the difficulties in its microbial synthesis, it holds promise because it may be less toxic.

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This study examined factors influencing the onset and progression of colorectal tumors, including patients' epidemiological data, tumor location (right-sided, left-sided, and rectal), histomorphology, perineural or intraneural invasion, lymph node status, immune reactions, mismatch repair (MMR) status, and commonly observed mutations. Our primary goal was to evaluate their predictive and prognostic value and interactions. We analyzed a retrospective cohort of 100 patients with colorectal adenocarcinoma diagnosed between 2020 and 2023, using formalin-fixed paraffin-embedded (FFPE) tumor blocks.

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Terminal Schwann cells (TSCs) are capable of regulating acetylcholine (ACh) release at the neuromuscular junction (NMJ). We have identified GABA as a gliotransmitter at mouse NMJs. When ACh activates α7 nicotinic ACh receptor (nAChRs) on TSCs, GABA is released and activates GABA receptors on the nerve terminal that subsequently reduce ACh release.

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Article Synopsis
  • * The study introduces new "fine-tuned" ChE inhibitors called PAMAM-calix-dendrimers, which were designed and synthesized with varying terminal fragments.
  • * Experimental results show that these dendrimers effectively inhibit human acetylcholinesterase and butyrylcholinesterase, with their activity linked to their structure, paving the way for future drug development.
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24 (BL24) is an efficient, non-pathogenic producer of 2,3-butanediol (2,3-BD). However, during inulin fermentation, the strain produces large amounts of exopolysaccharides (EPS), which interfere with the process' performance. The present study aims to investigate the effect that inactivation of the gene, encoding levansucrase in BL24, has on 2,3-BD production efficiency.

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The low solubility of α-tocopherol in water and its susceptibility to photodegradation make it difficult for biological systems to absorb this natural antioxidant. To overcome these limitations, α-tocopherol was encapsulated in low-toxicity nanocontainers, namely, niosomes based on Tween 80 and cholesterol. The niosomes were modified with cationic surfactants containing a carbamate fragment.

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Organizing and partitioning sets of chemical structures is of considerable practical significance, e.g., in compound library analysis and the postprocessing of screening hit lists.

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D-Mannose 2-epimerase (MEase) catalyzes the bioconversion between D-glucose and D-mannose. It is an important potential biocatalyst for large-scale production of D-mannose, a functional monosaccharide used in pharmaceutical and food industries. In this study, a new microbial MEase was characterized from Runella zeae DSM 19591.

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Article Synopsis
  • * While they can have some benefits, high levels of antinutrients can be bad for our health and stop us from getting nutrients we need.
  • * The study looks at different types of antinutrients and discusses how using fermentation can help reduce their levels in food, making it healthier for us to eat.
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The natural auxiliary function (NAF) approach is an approximation to decrease the size of the auxiliary basis set required for quantum chemical calculations utilizing the density fitting technique. It has been proven efficient to speed up various correlation models, such as second-order Møller-Plesset (MP2) theory and coupled-cluster methods. Here, for the first time, we discuss the theory of analytic derivatives for correlation methods employing the NAF approximation on the example of MP2.

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Article Synopsis
  • Surfactants, especially non-ionic ones, are crucial in pesticide formulations, improving effectiveness without altering solution properties like pH, but piperidinium surfactants with carbamate fragments might enhance efficacy more than conventional non-ionic types.
  • The study evaluated new piperidinium surfactants’ performance in enhancing imidacloprid, demonstrating that a 0.1% concentration substantially reduces the lethal dose required to combat the greenhouse whitefly pest.
  • Results indicate that these surfactants boost imidacloprid's effectiveness by increasing its concentration on leaf surfaces and aiding its penetration into plants, demonstrating their potential as effective adjuvants in pest control.
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The number of victims with damage to the great vessels has increased in recent years due to escalation of armed conflicts. Vascular damages comprise 3% of traumatic injuries in peacetime, and their incidence increases to 15% during hostilities. False aneurysms and traumatic arteriovenous fistulas follow vascular injury in 48.

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Food availability determines the amount of energy animals can acquire and allocate to reproduction and other necessary functions. Female animals that are food limited thus experience reduced energy available for reproduction. When this occurs, females may reduce frequency of reproductive events or the number or size of offspring per reproductive bout.

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Oats are one of the most useful and widespread cereal crops in the world. In permafrost conditions (Central Yakutia), based on metabolic changes in late summer-sown oat plants ( L.), the key processes involved in the cold acclimation of a valuable cereal species were identified.

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The unique properties of superparamagnetic iron oxide nanoparticles (SPIONs) enable their use as magnetic biosensors, targeted drug delivery, magnetothermia, magnetic resonance imaging, etc. Today, SPIONs are the only type of metal oxide nanoparticles approved for biomedical application. In this work, we analyzed the cellular response to the previously reported luminescent silica coated SPIONs of the two cell types: M-HeLa cells and primary motor neuron culture.

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Objective: Assessment of plasma and salivary acetylcholinesterase (AChE) activity in patients with amyotrophic lateral sclerosis (ALS) and in an animal model of the disease.

Material And Methods: We studied 41 participants, aged 31 to 71 years, including 17 patients with diagnosed ALS (ALS group, average age 62.3±2.

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Antimicrobial resistance to modern antibiotics stimulates the search for new ways to synthesize and modify antimicrobial drugs. The development of synthetic approaches that can easily change different fragments of the molecule is a promising solution to this problem. In this work, a synthetic approach was developed to obtain multivalent thiacalix[4]arene derivatives containing different number of amine and hydroxyl groups.

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R22 was isolated from a rice rhizosphere in Bulgaria. Its genome (assembled into 14 scaffolds) has a size of 4.08 Mbp and a G + C content of 46.

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A central event in the pathogenesis of Alzheimer's disease (AD) is the accumulation of senile plaques composed of aggregated amyloid-β (Aβ) peptides. The main class of drugs currently used for the treatment of AD are the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors. In this study, it has been shown that Aβ augmented AChE activity in vitro, maximum activation of 548 ± 5% was achieved following 48 h of incubation with 10 μM of Aβ, leading to a 7.

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This research is based on the concept that mitochondria are a promising target for anticancer therapy, including thatassociated with the use of oxidative phosphorylation blockers (mitochondrial poisons). Liposomes based on L-α-phosphatidylcholine (PC) and cholesterol (Chol) modified with cationic surfactants with triphenylphosphonium (TPPB-n, where n = 10, 12, 14, and 16) and imidazolium (IA-n(OH), where n = 10, 12, 14, and 16) head groups were obtained. The physicochemical characteristics of liposomes at different surfactant/lipid molar ratios were determined by dynamic/electrophoretic light scattering, transmission electron microscopy, and spectrophotometry.

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Cholinesterase inhibitors are a group of medicines that are widely used for the treatment of cognitive impairments accompanying Alzheimer's disease as well as for the treatment of pathological muscle weaknesses syndromes such as myasthenia gravis. The search for novel non-toxic and effective cholinesterase inhibitors for creating neuroprotective and neurotransmitter agents is an urgent interdisciplinary problem. For the first time, the application of water-soluble pillar[5]arenes containing amino acid residues as effective cholinesterase inhibitors was shown.

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Alzheimer disease (AD) is a widespread neurodegenerative disease characterized by the accumulation of oligomeric toxic forms of β-amyloid (Aβ1-42) and dysfunction of the cholinergic system in the different brain regions. However, the exact mechanisms of AD pathogenesis and the role of the nicotinic acetylcholine receptors (nAChRs) in the disease progression remain unclear. Here, we revealed a decreased expression of a number of the Ly6/uPAR proteins targeting nAChRs in the cerebellum of 2xTg-AD mice (model of early AD) in comparison with non-transgenic mice both at mRNA and protein levels.

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