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401.
Diana Garibo Ruiz Ekaterina Nefedova Nikolay N. Shkil Nikolay A. Shkil Roberto Luna Vazquez-Gomez Alexey Pestryakov Nina Bogdanchikova 《International journal of molecular sciences》2022,23(11)
The present work is a continuation of our translational research focusing on the use of silver nanoparticles (AgNPs) to solve the global problem of antibiotic resistance. In vivo fieldwork was done with 300 breeding farm cows with serous mastitis. Ex vivo assays revealed that after cow treatment with the antibiotic drug Spectromast LCTM, S. dysgalactiae susceptibility to 31 antibiotics dropped by 22.9%, but after treatment with Argovit–CTM AgNPs, it was raised by 13.1%. This was explained by the fact that the percentage of isolates with an efflux effect after Spectromast LC treatment resulted in an 8% increase, while Argovit-C-treatment caused a 19% decrease. The similarity of these results to our previous results on S. aureus isolates from mastitis cows treated with the antibiotic drug Lactobay and Argovit–CTM AgNPs was shown. So, mastitis treatments with Argovit-CTM AgNPs can partially return the activity of antibiotics towards S. dysgalactiae and S. aureus, while, in contrast, treatments with antibiotic drugs such as Spectromast LC and Lactobay enhance bacterial resistance to antibiotics. The results of this work strengthen the hope that in the future the use of AgNPs as efflux pump inhibitors will recover the activity of antibiotics, and thus will preserve the wide spectrum of antibiotics on the market. 相似文献
402.
Nataliya V. Yaglova Sergey S. Obernikhin Elina S. Tsomartova Valentin V. Yaglov Svetlana V. Nazimova Dibakhan A. Tsomartova Ekaterina P. Timokhina Elizaveta V. Chereshneva Marina Y. Ivanova Olga V. Payushina 《International journal of molecular sciences》2022,23(12)
The impact of endocrine-disrupting chemicals on the development and involution of the immune system is a possible reason for the increased incidence of disorders associated with inappropriate immune function. The thymus is a lymphoid and also an endocrine organ, and, accordingly, its development and functioning may be impaired by endocrine disruptors. The aim was to evaluate age-related thymus involution in mature rats exposed to the endocrine disruptor DDT during prenatal and postnatal ontogeny. Methodology included in vivo experiment on male Wistar rats exposed to low doses of DDT during prenatal and postnatal development and morphological assessment of thymic involution, including the immunohistochemical detection of proliferating thymocytes. The study was carried out at the early stage of involution. Results: DDT-exposed rats exhibited a normal anatomy, and the relative weight of the thymus was within the control ranges. Histological and immunohistochemical examinations revealed increased cellularity of the cortex and the medulla, higher content of lymphoblasts, and more intensive proliferation rate of thymocytes compared to the control. Evaluation of thymic epithelial cells revealed a higher rate of thymic corpuscles formation. Conclusion: The data obtained indicate that endocrine disrupter DDT disturbs postnatal development of the thymus. Low-dose exposure to DDT during ontogeny does not suppress growth rate but violates the developmental program of the thymus by slowing down the onset of age-related involution and maintaining high cell proliferation rate. It may result in excessive formation of thymus-dependent areas in peripheral lymphoid organs and altered immune response. 相似文献
403.
Michael V. Ugrumov Ekaterina N. Pavlova Anna A. Kolacheva Liliya K. Dilmukhametova Vsevolod V. Bogdanov Victor Blokhin Tatiana S. Pronina 《International journal of molecular sciences》2022,23(12)
Since the 1980s, the concept of dopamine-rich brain centers as clusters of only dopaminergic neurons has been fundamentally revised. It has been shown that, in addition to dopaminergic neurons, most of these centers contain neurons expressing one of the enzymes of dopamine synthesis: tyrosine hydroxylase (TH) or aromatic L-amino acid decarboxylase (AADC). We have obtained convincing evidence that in rats, the hypothalamic periventricular nucleus (PeVN) is one of the largest dopamine-rich centers, containing dopaminergic and monoenzymatic neurons. Indeed, using double immunostaining for TH and AADC, the PeVN was shown to contain almost three thousand dopaminergic and monoenzymatic neurons. According to high-performance liquid chromatography, PeVN contains L-DOPA and dopamine, which, apparently, are synthesized in monoenzymatic TH neurons and bienzymatic neurons, respectively. According to confocal microscopy, neurons (cell bodies, fibers), which were immunopositive only to TH, only to AADC, or both, are in close topographic relationships with each other and with the 3rd ventricle. These data suggest the mutual regulation of the neurons, as well as the delivery of dopamine and L-DOPA to the third ventricle, which is confirmed by their detection in the cerebrospinal fluid. Thus, evidence has been obtained that PeVN is one of the largest dopamine-rich centers of the brain, containing dopaminergic and monoenzymatic neurons. 相似文献
404.
Olga Kalinina Alexey Golovkin Ekaterina Zaikova Arthur Aquino Vadim Bezrukikh Olesya Melnik Elena Vasilieva Tatiana Karonova Igor Kudryavtsev Evgeny Shlyakhto 《International journal of molecular sciences》2022,23(16)
Hypercytokinemia, found in SARS-CoV-2 infection, contributes to multiple organ dysfunctions with acute respiratory distress syndrome, shock etc. The aim of this study was to describe cytokine storm signatures in patients with acute COVID-19 and to investigate their influence on severity of the infection. Plasma levels of 47 cytokines were investigated in 73 patients with moderate and severe COVID-19 (41 and 32, respectively) and 11 healthy donors (HD). The most elevated levels comparing patients and the HD were observed for seven pro-inflammatory cytokines (IL-6, IL-8, IL-15, IL-18, IL-27, IFNγ, TNFα), three chemokines (GROα, IP-10, MIG), two anti-inflammatory cytokines (IL-1RA, IL-10), and two growth factors (G-CSF, M-CSF). The patients with severe disease had significantly higher levels of FGF-2/FGF-basic, IL-1β, and IL-7 compared to the HD. The two groups of patients differed from each other only based on the levels of EGF, eotaxin, and IL-12 p40. Pneumonia lung injury, characterized by computer tomography, positively correlated with levels of EGF, IP-10, MCP-3 levels and negatively with IL-12 p40. Pro-inflammatory factors including IL-6, TNFα, and IP-10 negatively correlated with the frequency of the circulating T-helper17-like cells (Th17-like) and follicular Th cells that are crucial to develop SARS-CoV-2-specific plasma cells and memory B cells. Obtained data on the cytokine levels illustrate their influence on progression and severity of COVID-19. 相似文献
405.
406.
Ryan Andris Timofey Averianov Ekaterina Pomerantseva 《Journal of the American Ceramic Society》2023,106(1):120-132
Chemically preintercalated dopamine (DOPA) molecules were used as both a reducing agent and a carbon precursor to prepare δ-V2O5·nH2O/C, H2V3O8/C, VO2(B)/C, and V2O3/C nanocomposites via hydrothermal treatment or hydrothermal treatment followed by annealing under Ar flow. We found that the phase composition and morphology of the produced composites are influenced by the DOPA:V2O5 ratio used to synthesize (DOPA)xV2O5 precursors through DOPA diffusion into the interlayer region of the δ-V2O5·nH2O framework. The increase of DOPA concentration in the reaction mixture led to a more pronounced reduction of vanadium and a higher fraction of carbon in the composites’ structure, as evidenced by X-ray photoelectron spectroscopy and Raman spectroscopy measurements. The electrochemical charge storage properties of the synthesized nanocomposites were evaluated in Li-ion cells with nonaqueous electrolytes. δ-V2O5·nH2O/C, H2V3O8/C, VO2(B)/C, and V2O3/C electrodes delivered high initial capacities of 214, 252, 279, and 637 mAh g–1, respectively. The insights provided by this investigation open up the possibility of creating new nanocomposite oxide/carbon electrodes for a variety of applications, such as energy storage, sensing, and electrochromic devices. 相似文献
407.
Ekaterina Podlesnaia Princess Gerald Inangha James Vesenka Martin Seyring Hans-Jürgen Hempel Markus Rettenmayr Andrea Csáki Wolfgang Fritzsche 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(22):2204810
Nanoparticle synthesis has drawn great attention in the last decades. The study of crystal growth mechanisms and optimization of the existing methods lead to the increasing accessibility of nanomaterials, such as gold nanotriangles which have great potential in the fields of plasmonics and catalysis. To form such structures, a careful balance of reaction parameters has to be maintained. Herein, a novel synthesis of gold nanotriangles from seeds derived with a micromixer, which provides a highly efficient mixing and simple parameter control is reported. The impact of the implemented reactor on the primary seed characteristics is investigated. The following growth steps are studied to reveal the phenomena affecting the shape yield. The use of microfluidic seeds led to the formation of well-defined triangles with a narrower size distribution compared to the entirely conventional batch synthesis. A shortened two-step procedure for the formation of triangles directly from primary seeds, granting an express but robust synthesis is further described. Moreover, the need for a thorough study of seed crystallinity depending on the synthesis conditions, which – together with additional parameter optimization – will bring a new perspective to the use of micromixers which are promising for scaling up nanomaterial production is highlighted. 相似文献
408.
Daniil A. Rusanov Samah Mutasim Alfadul Ekaterina Yu. Portnyagina Dr. Eugenia A. Silyanova Nikita A. Kuznetsov Kirill E. Podpovetny Prof. Dr. Alexander V. Samet Prof. Dr. Victor V. Semenov Dr. Maria V. Babak 《Chembiochem : a European journal of chemical biology》2023,24(11):e202300161
Since the discovery of anticancer properties of a naturally occurring hexacyclic marine alkaloid Lamellarin D, the attempts have been made to prepare its synthetic analogues and elucidate the effects of each structural component on their activity profile. While F-ring-free, A-ring-free and B-ring-open lamellarins are known, E-ring-free analogues have never been investigated. In this work, we developed a facile and straightforward synthetic method toward E-ring-free lamellarin analogues based on the [3+2]-cycloaddition. For the first time, we prepared several pentacyclic lamellarin analogues without E-ring in their structure and assessed their cytotoxicity in a panel of cancer cell lines in comparison with several hexacyclic lamellarins. E-ring-free lamellarins were devoid of cytotoxicity due to their poor solubility in cellular environment. 相似文献
409.
410.