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1.
Benef Microbes ; 15(2): 145-164, 2024 Feb 22.
Article in English | MEDLINE | ID: mdl-38412868

ABSTRACT

COVID-19 is caused by an airborne virus, SARS-CoV-2. The upper respiratory tract (URT) is, therefore, the first system to endure the attack. Inhabited by an assemblage of microbial communities, a healthy URT wards off the invasion. However, once invaded, it becomes destabilised, which could be crucial to the establishment and progression of the infection. We examined 696 URT samples collected from 285 COVID-19 patients at three time-points throughout their hospital stay and 100 URT samples from 100 healthy controls. We used 16S ribosomal RNA sequencing to evaluate the abundance of various bacterial taxa, α-diversity, and ß-diversity of the URT microbiome. Ordinary least squares regression was used to establish associations between the variables, with age, sex, and antibiotics as covariates. The URT microbiome in the COVID-19 patients was distinctively different from that of healthy controls. In COVID-19 patients, the abundance of 16 genera was significantly reduced. A total of 47 genera were specific to patients, whereas only 2 were unique to controls. The URT samples collected at admission differed more from the control than from the samples collected at later stages of treatment. The following four genera originally depleted in the patients grew significantly by the end of treatment: Fusobacterium, Haemophilus, Neisseria, and Stenotrophomonas. Our findings strongly suggest that SARS-CoV-2 caused significant changes in the URT microbiome, including the emergence of numerous atypical taxa. These findings may indicate increased instability of the URT microbiome in COVID-19 patients. In the course of the treatment, the microbial composition of the URT of COVID-19 patients tended toward that of controls. These microbial changes may be interpreted as markers of recovery.


Subject(s)
Bacteria , COVID-19 , Microbiota , RNA, Ribosomal, 16S , Respiratory System , SARS-CoV-2 , Humans , COVID-19/microbiology , Male , Female , Middle Aged , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , RNA, Ribosomal, 16S/genetics , Aged , SARS-CoV-2/genetics , Respiratory System/microbiology , Respiratory System/virology , Adult , Aged, 80 and over
2.
Mol Biol (Mosk) ; 57(6): 1077-1083, 2023.
Article in Russian | MEDLINE | ID: mdl-38062961

ABSTRACT

Melittin, a peptide from bee venom, was found to be able to interact with many proteins, including calmodulin target proteins and ion-transporting P-type ATPases. It is assumed that melittin mimics a protein module involved in protein-protein interactions within cells. Previously, a Na^(+)/K^(+)-ATPase containing the α1 isoform of the catalytic subunit was found to co-precipitate with a protein with a molecular weight of about 70 κDa that interacts with antibodies against melittin by cross immunoprecipitation. In the presence of a specific Na^(+)/K^(+)-ATPase inhibitor (ouabain), the amount of protein with a molecular weight of 70 κDa interacting with Na^(+)/K^(+)-ATPase increases. In order to identify melittin-like protein from murine kidney homogenate, a fraction of melittin-like proteins with a molecular weight of approximately 70 κDa was obtained using affinity chromatography with immobilized antibodies specific to melittin. By mass spectrometry analysis, the obtained protein fraction was found to contain three molecular chaperones of Hsp70 superfamily: mitochondrial mtHsp70 (mortalin), Hsp73, Grp78 (BiP) of endoplasmic reticulum. These data suggest that chaperones from the HSP-70 superfamily contain a melittin-like module.


Subject(s)
Melitten , Sodium-Potassium-Exchanging ATPase , Mice , Animals , Melitten/chemistry , Melitten/metabolism , Melitten/pharmacology , Sodium-Potassium-Exchanging ATPase/chemistry , Molecular Weight , Ouabain/pharmacology , Peptides/metabolism , Molecular Chaperones/metabolism
3.
Mol Biol (Mosk) ; 57(6): 1188-1198, 2023.
Article in Russian | MEDLINE | ID: mdl-38062968

ABSTRACT

Metabolic stress caused by a lack of glucose significantly affects the state of red blood cells, where glycolysis is the main pathway for the production of ATP. Hypoglycemia can be both physiological (occurring during fasting and heavy physical exertion) and pathological (accompanying a number of diseases, such as diabetes mellitus). In this study, we have characterized the state of isolated erythrocytes under metabolic stress caused by the absence of glucose. It was established that 24 h of incubation of the erythrocytes in a glucose-free medium to simulate blood plasma led to a two-fold decrease in the ATP level into them. The cell size, as well as intracellular sodium concentration increased. These findings could be the result of a disruption in ion transporter functioning because of a decrease in the ATP level. The calcium level remained unchanged. With a lack of glucose in the medium of isolated erythrocytes, there was no increase in ROS and a significant change in the level of nitric oxide, while the level of the main low-molecular weight thiol of cells, glutathione (GSH) decreased by almost 2 times. It was found that the metabolic stress of isolated red blood cells induced hemoglobin glutathionylation despite the absence of ROS growth. The cause was the lack of ATP, which led to a decrease in the level of GSH because of the inhibition of its synthesis and, probably, due to a decrease in the NADPH level required for glutathione (GSSG) reduction and protein deglutathionylation. Thus, erythrocyte metabolic stress induced hemoglobin glutathionylation, which is not associated with an increase in ROS. This may have an important physiological significance, since glutathionylation of hemoglobin changes its affinity for oxygen.


Subject(s)
Glutathione , Hemoglobins , Glutathione Disulfide/analysis , Glutathione Disulfide/metabolism , Reactive Oxygen Species/metabolism , Oxidation-Reduction , Glutathione/analysis , Glutathione/metabolism , Hemoglobins/analysis , Hemoglobins/metabolism , Erythrocytes/chemistry , Erythrocytes/metabolism , Oxidative Stress , Glucose/analysis , Glucose/metabolism , Adenosine Triphosphate
4.
Article in Russian | MEDLINE | ID: mdl-35236068

ABSTRACT

The article dwells upon the history of the discovery of the Tumnin mineral spring, the establishment and development of the Far Eastern health resort «Goryachy Klyuch,¼ located in the basin of Chope creek, a tributary of the largest river in the eastern macroslope of Sikhote Alin, Tumnin river, located 25 km from the Strait of Tartary. A historical sketch since the first mentioning of the Tumnin mineral spring from 1903 to the present day, as well as the results of hydrogeological expeditions to determine the chemical composition and α-activity of Tumnin mineral water at different periods, are presented. A contribution of a geological expedition that established a large deep-lying tectonic structure permeable to upwelling thermal water flows is described. The role of the staff of the physiotherapy and balneology department of the Khabarovsk Medical Institute in the study of the mechanism of action and clinical effectiveness of the Tumnin mineral water is addressed. A balneological characteristic of nitric and siliceous thermal water, the basic therapeutic factor of «Goryachy Klyuch¼ health resort, which has always been popular among the Far East residents, but gained special importance and appreciation of patients during the pandemic of new coronavirus infection, is given. Currently, in the health resort «Goryachy Klyuch¼, patients with skin diseases, musculoskeletal, gynecologic, neurologic diseases, digestive tract disorders, metabolic conditions, upper airways, cardiovascular disorders, occupational diseases are treated using balneotherapy and other methods of non-drug therapy. At present, the health resort «Goryachy Klyuch¼ is going through a difficult but interesting period of improvement of recreation opportunities for the Far East residents.


Subject(s)
Balneology , Mineral Waters , Skin Diseases , Female , Health Resorts , Humans , Mineral Waters/therapeutic use , Minerals , Skin Diseases/drug therapy
5.
Heliyon ; 7(9): e08088, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34632152

ABSTRACT

High-salt consumption contributes to the development of hypertension and is considered an independent risk factor for vascular remodelling, cardiac hypertrophy and stroke incidence. Alterations in NO production, inflammation and endothelial cell stiffening are considered now as plausible mediators of cardiovascular dysfunction. We studied early responses of endothelial cells (HUVEC) caused by a moderate increase in extracellular sodium concentration. Exposure of HUVEC to elevated sodium within the physiological range up to 24 h is accompanied by changes in monovalent cations fluxes and Na,K-ATPase activation, and, in turn, results in a significant decrease in the content of PTGS2, IL6 and IL1LR1 mRNAs. The expression of NOS3 and FOS genes, as well as the abundance of cytosolic and nuclear NFAT5 protein, remained unchanged. We assessed the mechanical properties of endothelial cells by estimating Young's modulus and equivalent elastic constant using atomic force and interference microscopy, respectively. These parameters were unaffected by elevated-salt exposure for 24 h. The data obtained suggest that even small and short-term elevations of extracellular sodium concentration affect the expression of genes involved in the control of endothelial function through the Na+ i/K+ i-dependent mechanism(s).

6.
Vestn Otorinolaringol ; 86(1): 46-50, 2021.
Article in Russian | MEDLINE | ID: mdl-33720651

ABSTRACT

In an open, randomized prospective comparative clinical study in parallel groups of patients with a diagnosis of acute respiratory infection, acute rhinosinusitis, 107 children aged 4-5 years took part. The purpose of this study was to compare the effectiveness of various treatment regimens for acute viral rhinosinusitis in children. We compared the treatment effectiveness of acute viral rhinosinusitis using the herbal medicine Sinupret in the form of oral drops, standard treatment and standard treatment supplemented with topical antibacterial drugs. The objectivity of treatment effectiveness evaluation was based on the complaints' dynamics, the changes' presence in the mucous membrane of the nasal cavity within 10 days: at the initial visit, after 3 days, on the 7th and 10th days after the initial examination. A follow-up visit was also scheduled for the 14th day. The analysis of the obtained data revealed that the Sinupret usage in the complex treatment of children with viral etiology acute rhinosinusitis contributes to a more pronounced positive symptoms' dynamics compared to children who did not receive Sinupret. Sinupret eliminates mucostasis, which contributes to a faster restoration of the drainage and ventilation function of the auditory tube, restores mucociliary clearance, improves the condition and well-being of children, improves the effectiveness of therapy and shortens the treatment time.


Subject(s)
Rhinitis , Sinusitis , Acute Disease , Child , Child, Preschool , Humans , Mucociliary Clearance , Phytotherapy , Prospective Studies , Rhinitis/diagnosis , Rhinitis/drug therapy , Sinusitis/diagnosis , Sinusitis/drug therapy
7.
PLoS One ; 15(9): e0239147, 2020.
Article in English | MEDLINE | ID: mdl-32960928

ABSTRACT

Ever decreasing efficiency of antibiotic treatment due to growing antibiotic resistance of pathogenic bacteria is a critical issue in clinical practice. The two generally accepted major approaches to this problem are the search for new antibiotics and the development of antibiotic adjuvants to enhance the antimicrobial activity of known compounds. It was therefore the aim of the present study to test whether alkylresorcinols, a class of phenolic lipids, can be used as adjuvants to potentiate the effect of various classes of antibiotics. Alkylresorcinols were combined with 12 clinically used antibiotics. Growth-inhibiting activity against a broad range of pro- and eukaryotic microorganisms was determined. Test organisms did comprise 10 bacterial and 2 fungal collection strains, including E. coli and S. aureus, and clinical isolates of K. pneumoniae. The highest adjuvant activity was observed in the case of 4-hexylresorcinol (4-HR), a natural compound found in plants with antimicrobial activity. 50% of the minimal inhibitory concentration (MIC) of 4-HR caused an up to 50-fold decrease in the MIC of antibiotics of various classes. Application of 4-HR as an adjuvant revealed its efficiency against germination of bacterial dormant forms (spores) and prevented formation of antibiotic-tolerant persister cells. Using an in vivo mouse model of K. pneumoniae-induced sepsis, we could demonstrate that the combination of 4-HR and polymyxin was highly effective. 75% of animals were free of infection after treatment as compared to none of the animals receiving the antibiotic alone. We conclude that alkylresorcinols such as 4-HR can be used as an adjuvant to increase the efficiency of several known antibiotics. We suggest that by this approach the risk for development of genetically determined antibiotic resistance can be minimized due to the multimodal mode of action of 4-HR.


Subject(s)
Adjuvants, Pharmaceutic/pharmacology , Anti-Bacterial Agents/pharmacology , Hexylresorcinol/pharmacology , Klebsiella Infections/drug therapy , Sepsis/drug therapy , Adjuvants, Pharmaceutic/therapeutic use , Animals , Anti-Bacterial Agents/therapeutic use , Disease Models, Animal , Drug Resistance, Multiple, Bacterial , Drug Synergism , Drug Therapy, Combination/methods , Escherichia coli/drug effects , Female , Hexylresorcinol/therapeutic use , Humans , Klebsiella Infections/microbiology , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/isolation & purification , Mice , Microbial Sensitivity Tests , Polymyxins/pharmacology , Polymyxins/therapeutic use , Sepsis/microbiology , Staphylococcus aureus/drug effects
8.
Article in Russian | MEDLINE | ID: mdl-32592576

ABSTRACT

The article is devoted to the history of the creation and establishment of the Far Eastern resort «Talaya¼, located in the Far North of Russia, in the Magadan Region among the hills of the Kolyma Range, in the valley of the Talaya River. A historical essay is presented from 1868 to the present days, including periods of the resort's development at various stages of Russia's formation (pre-revolutionary, post-revolutionary periods, the era of developed socialism, present times). The contribution of resort doctors, geologists, employees of research institutes to the study of the mechanism of action and clinical effectiveness of the use of Tal mineral water is described. The balneological characteristic of nitrogen-siliceous thermal water, the main therapeutic factor of the Talaya resort, is given. Currently, the Talaya sanatorium is providing the treatment of patients with diseases of the skin, musculoskeletal system, gynecological, neurological diseases, diseases of the digestive system, metabolism, upper respiratory tract, cardiovascular system, occupational diseases using balneotherapy, mud therapy and others methods of non-drug therapy. Hundreds of thousands of northerners were healed by the Kolyma health resort, which gained fame as the «Northern Pearl¼. Today, during the reorganization of health care, the Talaya sanatorium is going through a difficult but interesting period in improving the possibilities of healing the inhabitants of the northern regions of Russia.


Subject(s)
Balneology , Mineral Waters , Mud Therapy , Health Resorts , Humans , Russia
9.
Bull Exp Biol Med ; 169(1): 1-4, 2020 May.
Article in English | MEDLINE | ID: mdl-32495173

ABSTRACT

The effects of dynamic and static load on the intracellular concentrations of sodium [Formula: see text] and potassium (K+i) in m. soleus and m. biceps, respectively, were studied in mice. Both dynamic (swimming for 60 min) and static (hanging on the grid for 40 min) load led to a 2-fold increase in [Formula: see text] level, a decrease in K+i concentration by 25-35%, and 3-4-fold increase in the [Formula: see text] ratio. These effects of dynamic and static loads on the studied parameters remained unchanged in mice subjected to regular physical exercise (swimming or hanging on the grid for 1 h a day over 4 weeks). Our results suggest that dissipation of sodium and potassium transmembrane gradients during physical exercise can be considered as a factor of regulation of functional activity of skeletal muscles, which includes changes in transcription and translation of myokines observed previously.


Subject(s)
Muscle, Skeletal/metabolism , Physical Conditioning, Animal/physiology , Potassium/metabolism , Sodium/metabolism , Animals , Ions/analysis , Ions/metabolism , Male , Mice , Mice, Inbred C57BL , Muscle Stretching Exercises/physiology , Muscle, Skeletal/chemistry , Potassium/analysis , Sodium/analysis , Swimming/physiology , Weight-Bearing/physiology
10.
Biochemistry (Mosc) ; 85(4): 507-515, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32569558

ABSTRACT

Long-term study on the identification of Na,K-ATPase endogenous inhibitors in mammalian tissues has resulted in the discovery of ouabain, marinobufagenin (MBG), and other cardiotonic steroids (CTS) in the blood plasma. Production of ouabain and MBG is increased in essential hypertension and other diseases associated with hypervolemia. Here, we compared the effects of ouabain and MBG on the Na,K-ATPase activity (measured as the transport of Na+, K+, and Rb+ ions) and proliferation and death of human renal epithelial cells (HRECs) and human umbilical vein endothelial cells (HUVEC) expressing α1-Na,K-ATPase. Ouabain concentration that provided the half-maximal inhibition of the Rb+ influx (IC50) into HRECs and HUVECs was 0.07 µM. In both types of cells, the IC50 values for MBG were 10 times higher than for ouabain. Incubation of HREC and HUVEC with 0.001-0.01 µM ouabain for 30 h resulted in 40% increase in the [3H]thymidine incorporation into DNA; further elevation of ouabain concentration to 0.1 µM completely suppressed DNA synthesis. MBG at the concentration of 0.1 µM activated DNA synthesis by 25% in HRECs, but not in HUVECs; 1 µM MBG completely inhibited DNA synthesis in HRECs and by 50% in HUVECs. In contrast to HRECs, incubation of HUVECs in the serum-free medium induced apoptosis, which was almost completely suppressed by ouabain and MBG at the concentrations of 0.1 and 3 µM, respectively. Based on these data, we can conclude that (i) the effect of MBG at the concentrations detected in the blood plasma (<0.01 µM) on HRECs and HUVECs was not due to the changes in the [Na+]i/[K+]i ratio; (ii) the effect of physiological concentrations of ouabain on these cells might be mediated by the activation of Na,K-ATPase, leading to cell proliferation.


Subject(s)
Bufanolides/pharmacology , Cell Proliferation , Endothelial Cells/physiology , Epithelial Cells/physiology , Heart/physiology , Ouabain/pharmacology , Cardiotonic Agents/pharmacology , Cell Death , Cells, Cultured , Endothelial Cells/drug effects , Epithelial Cells/drug effects , Heart/drug effects , Humans , Ion Transport , Vasoconstrictor Agents/pharmacology
11.
J Phys Condens Matter ; 32(36): 365404, 2020 May 12.
Article in English | MEDLINE | ID: mdl-32396885

ABSTRACT

Thermally-activated phase transitions in Pt/Mn/Fe thin films were investigated by a combination of x-ray diffraction, transmission electron microscopy, secondary neutral mass spectrometry depth profiling, atomic force microscopy, and magnetic properties measurements. Post-annealing was carried out in vacuum to different temperatures up to 620 °C. Initially, at temperatures between 280 °C-450 °C first L10-MnPt is formed at the Mn/Pt interface followed by the most likely formation of metastable bcc Fe3Pt, which gets transformed by further annealing to fcc Fe3Pt and eventually to chemically ordered L12-Fe3Pt. The final product after annealing at 620 °C consists of two interesting phases, which are relevant for spintronic applications, antiferromagnetic L10-MnPt with addition of Fe and ferromagnetic L12-Fe3Pt, consistent with the initial element composition.

12.
Exp Oncol ; 42(1): 16-24, 2020 03.
Article in English | MEDLINE | ID: mdl-32231196

ABSTRACT

Response of chronic lymphocytic leukemia (CLL) patients to classical chemoimmunotherapy that remains the main strategy in treatment of this disease is strikingly variable. This issue requires the finding of biomarkers which could predict efficiency of drug administration and choose the best treatment option for each patient individually. The aim of this study was to find out association between cell surface receptors expression levels and CLL B cells sensitivity to chemotherapeutic drugs ex vivo. MATERIALS AND METHODS: The study was performed on malignant B cells isolated from peripheral blood of primary CLL patients. Flow cytometry, qPCR, ex vivo drug sensitivity assay, and cell viability assay were used in this study. RESULTS: The high CD5 expression level was linked to better bendamustine (BEN) and cyclophosphamide (CP) CLL B cells response in contrast to B cells with low CD5 expression. Sensitivity of CLL B cells to CP also could be predicted by high level of CD20 expression. Expression of CD38 and high levels of CD37 and CD40 showed CLL B cells resistance to BEN ex vivo. CLL B cells sensitivity to analyzed chemotherapeutic drugs was not dependent on CD22 expression status. The CD180 expression was detected in CLL B cells which were more susceptible to fludarabine and cyclophosphamide (FC) combinatory action. CLL B cells that coexpressed CD150 and CD180 on the cell surface were characterized by significantly decreased cell viability under fludarabine (FLU) exposure alone or FC in comparison with CD150-CD180- B cells. Cell surface expression level of CD150 was not associated with CLL B cells chemosensitivity. However, high mRNA expression level of mCD150 isoform in CLL B cells was linked to their FLU sensitivity and CP resistance, while high nCD150 mRNA expression level showed resistance to FLU. Simultaneous CD150 and CD180 ligation increased FLU resistance, but BEN susceptibility of CLL B cells. CD150 and CD180 alone or in combination are involved in upregulation of CD20 cell surface expression. CONCLUSION: Expression status of the CD5, CD20, CD37, CD38, CD40, CD150, and CD180 cell surface receptors could be used in prediction CLL B cells sensitivity to FLU, CP, BEN and FC ex vivo. Moreover, CD150 and CD180 receptors are involved in regulation of CLL B cells susceptibility to FLU and BEN. The CD150 and CD180 are positive regulators of CD20 expression that could make CD150+CD180+ CLL B cells more responsive to CD20-based immunotherapy.


Subject(s)
Antigens, CD/metabolism , Antineoplastic Agents/pharmacology , B-Lymphocytes/drug effects , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Leukocytes, Mononuclear/drug effects , Receptors, Cell Surface/metabolism , B-Lymphocytes/metabolism , B-Lymphocytes/pathology , Bendamustine Hydrochloride/pharmacology , Cell Line, Tumor , Cell Survival/drug effects , Cyclophosphamide/pharmacology , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/metabolism , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Leukocytes, Mononuclear/metabolism , Leukocytes, Mononuclear/pathology , Vidarabine/analogs & derivatives , Vidarabine/pharmacology
13.
Article in Russian | MEDLINE | ID: mdl-31880765

ABSTRACT

BACKGROUND: It is necessary to develop a balneotherapeutic and tourist-recreational complex on Iturup Island (hereinafter referred to as Iturup Island). This investigation was conducted in the framework of the federal target program 'Socioeconomic development of the Kuril Islands, Sakhalin Region, for 2007-2015' under No. 478 dated 08.09.06. OBJECTIVE: To characterize the balneological resource of the 'Zharkie Vody' (Hot Water) spring on Iturup Island. MATERIAL AND METHODS: Expeditionary studies were conducted at the 'Zharkie Vody' spring located near the village of Raidovo (Iturup Island): its water samples were taken and chemically analyzed in a certified laboratory in Khabarovsk; the biological activity of the mineral water was studied using the Cyto-Expert portable non-invasive diagnostic equipment adapted to the expeditionary conditions. RESULTS: The mineral water from the 'Zharkie Vody' deposit (Iturup Island) is weakly mineralized siliceous sulfate-bicarbonate-chloride calcium-sodium thermal and has an activation function on living cell structures. CONCLUSION: The data obtained from the studies created the prerequisites for setting up a balneotherapy complex near the 'Zharkie Vody' on Iturup Island and provide optimistic forecasts for the further study of this deposit.


Subject(s)
Balneology , Mineral Waters , Humans , Russia
14.
Biochemistry (Mosc) ; 84(11): 1280-1295, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31760918

ABSTRACT

Maintenance of non-equilibrium Na+ and K+ distribution between cytoplasm and extracellular medium suggests existence of sensors responding with conformational transitions to the changes of these monovalent cations' intracellular concentration. Molecular nature of monovalent cation sensors has been established in Na,K-ATPase, G-protein-coupled receptors, and heat shock proteins structural studies. Recently, it was found that changes in Na+ and K+ intracellular concentration are the key factors in the transcription and translation control, respectively. In this review, we summarize results of these studies and discuss physiological and pathophysiological significance of Na+i,K+i-dependent gene expression regulation mechanism.


Subject(s)
Potassium/metabolism , Sodium-Potassium-Exchanging ATPase/metabolism , Sodium/metabolism , Animals , Cations, Monovalent/chemistry , Cytoplasm/metabolism , Heat-Shock Proteins/metabolism , Potassium/chemistry , Protein Biosynthesis , Sodium/chemistry , Transcription, Genetic
15.
J Phys Condens Matter ; 31(28): 285401, 2019 Jul 17.
Article in English | MEDLINE | ID: mdl-30952149

ABSTRACT

X-ray diffraction (XRD), secondary neutral mass spectrometry (SNMS) depth profiling, and electrical resistivity measurements were used to follow the phase transformations in Pt/Fe bi-layered thin films during annealing. Initially, the electrical resistivity increases linearly with temperature up to 150 °C due to the contribution of phonon scattering of the metallic Pt and Fe bilayer. Further increase of the annealing temperature leads to a steeper linear increase, which is associated with the initial formation of the chemically disordered A1-phase followed by the formation of the chemically ordered L10-FePt phase, as confirmed by XRD and SNMS studies. Finally, at about 620 °C the single L10-FePt phase has formed throughout the film. Moreover, the electrical resistivity contains also the magnetic contribution to the total resistivity. In this case, the loss in magnetic order is indicated by a change in temperature dependence of the resistivity at about 310 °C, representing the Curie temperature of the initially formed A1-FePt alloy, while the finally formed L10-FePt alloy reveals a higher magnetic transition temperature of about 410 °C. In this study, it has been demonstrated that resistometry in combination with structural and chemical analysis provides valuable information on diffusion processes, structural phase formations and its stability range, as well as on the magnetic transition temperature.

16.
J Antimicrob Chemother ; 73(suppl_5): v14-v21, 2018 04 01.
Article in English | MEDLINE | ID: mdl-29659881

ABSTRACT

Objectives: To determine antibiotic susceptibility in isolates of Streptococcus pneumoniae and Haemophilus influenzae collected in 2014-16 from Russia. Methods: MICs were determined by CLSI broth microdilution and susceptibility was assessed using CLSI, EUCAST and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. Results: A total of 279 S. pneumoniae and 279 H. influenzae were collected. Overall, 67.0% of S. pneumoniae were penicillin susceptible by CLSI oral/EUCAST and 93.2% by CLSI intravenous (iv) breakpoints. All were fluoroquinolone susceptible, with amoxicillin, amoxicillin/clavulanic acid and ceftriaxone susceptibility ≥92.8% by CLSI and PK/PD breakpoints. Isolates showed lower susceptibility to cefuroxime, cefaclor, macrolides and trimethoprim/sulfamethoxazole by CLSI criteria: 85.0%, 76.7%, 68.8% and 67.7%, respectively. Generally, susceptibility was slightly lower by EUCAST criteria, except for cefaclor, for which the difference in susceptibility was much greater. Penicillin-resistant isolates had low susceptibility (≤60%) to all agents except fluoroquinolones. All 279 H. influenzae were ceftriaxone susceptible, 15.4% were ß-lactamase positive and ≥97.5% were amoxicillin/clavulanic acid susceptible (CLSI, EUCAST and PK/PD breakpoints). Four isolates were fluoroquinolone non-susceptible by current EUCAST criteria. A major discrepancy was found with azithromycin susceptibility between CLSI (99.3%) and EUCAST and PK/PD (2.2%) breakpoints. Trimethoprim/sulfamethoxazole was poorly active (62.7% susceptible). Conclusions: Susceptibility to penicillin (oral), macrolides and trimethoprim/sulfamethoxazole was low in S. pneumoniae from Russia. However, isolates were fully susceptible to fluoroquinolones and ≥92.8% were susceptible to amoxicillin, amoxicillin/clavulanic acid and ceftriaxone. Isolates of H. influenzae only showed reduced susceptibility to ampicillin, cefaclor, clarithromycin and trimethoprim/sulfamethoxazole. Some differences were detected between CLSI, EUCAST and PK/PD breakpoints, especially with cefaclor, cefuroxime and macrolides. These data suggest further efforts are required to harmonize international breakpoints.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Multiple, Bacterial , Epidemiological Monitoring , Haemophilus influenzae/drug effects , Streptococcus pneumoniae/drug effects , Adolescent , Adult , Aged , Amoxicillin/pharmacokinetics , Amoxicillin/pharmacology , Amoxicillin-Potassium Clavulanate Combination/pharmacokinetics , Amoxicillin-Potassium Clavulanate Combination/pharmacology , Anti-Bacterial Agents/pharmacokinetics , Child , Community-Acquired Infections/epidemiology , Community-Acquired Infections/microbiology , Haemophilus Infections/epidemiology , Humans , Macrolides/pharmacokinetics , Macrolides/pharmacology , Microbial Sensitivity Tests , Middle Aged , Pneumococcal Infections/epidemiology , Respiratory Tract Infections/epidemiology , Respiratory Tract Infections/microbiology , Russia/epidemiology , Surveys and Questionnaires , Young Adult
17.
Exp Oncol ; 39(4): 291-298, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29284783

ABSTRACT

BACKGROUND: Sequential stages of B-cell development is stringently coordinated by transcription factors (TFs) network that include B-lineage commitment TFs (Ikaros, Runx1/Cbfb, E2A, and FOXO1), B-lineage maintenance TFs (EBF1 and PAX5) and stage specific set of TFs (IRF4, IRF8, BCL6, BLIMP1). Deregulation of TFs expression and activity is often occurs in malignant B cells. The aim of this study was to evaluate TFs expression in chronic lymphocytic leukemia cells taking into consideration CD150 cell surface expression. From other side we attempted to regulate TFs expression via CD150 and CD180 cell surface receptors. MATERIALS AND METHODS: Studies were performed on normal peripheral blood B-cell subpopulations and chronic lymphocytic leukemia (CLL) cells isolated from peripheral blood of 67 primary untreated patients with CLL. Evaluation of TFs expression was performed on mRNA level using qRT-PCR and on protein level by western blot analysis. RESULTS: Median of PAX5 and EBF1 mRNA expression was higher in cell surface CD150 positive (csCD150+) compared to csCD150- CLL cases or normal CD19+ and CD19+CD5+ B-cell subsets. Differences in mRNA expression of IRF8, IRF4 and BLIMP1 between studied groups of CLL and normal B cells were not revealed. All CLL cases were characterized by downregulated expression of PU.1 and BCL6 mRNAs in comparison to normal B cells. At the same time elevated SPIB mRNA expression level was restricted to CLL cells. Protein expression of IRF4, IRF8 and BCL6 was uniformly distributed between csCD150- and csCD150+ CLL cases. PU.1 protein and CD20 that is direct PU.1 target gene positively correlated with CD150 cell surface expression on CLL cells. Ligation of CD150 and CD180 alone or in combination upregulated IRF8 and PU.1 while downregulated the IRF4 mRNA expression. Signaling via CD150 or CD180 alone elevated the level of BCL6 mRNA. Strong downregulation of IRF4 mRNA was observed after CD150, CD180 or CD150 andCD180 coligation on CLL cells. We found that in CLL cells CD150 is a negative regulator of SPIB while CD180 is involved in upregulation of EBF1 expression level. Moreover, CD180 ligation on CLL cells caused increase of CD150 mRNA level that is a one of the EBF1 target genes. CONCLUSIONS: Analysis of TFs expression profile revealed upregulated SPIB mRNA level and downregulated PU.1 in CLL cells. CD150 and CD180 receptors may modulate transcriptional program in CLL cells by regulating the TFs expression levels.


Subject(s)
Antigens, CD/metabolism , Gene Expression Regulation, Neoplastic/physiology , Leukemia, Lymphocytic, Chronic, B-Cell/metabolism , Signaling Lymphocytic Activation Molecule Family Member 1/metabolism , Transcription Factors/biosynthesis , Humans
18.
J Glob Antimicrob Resist ; 8: 148-156, 2017 03.
Article in English | MEDLINE | ID: mdl-28167308

ABSTRACT

OBJECTIVES: Infections that are inadequately treated owing to acquired bacterial resistance are a leading cause of mortality. Rates of multidrug-resistant bacteria are rising, resulting in increased antibiotic failures and worsening patient outcomes. Mathematical modelling makes it possible to predict the future spread of bacterial antimicrobial resistance. The aim of this study was to construct a mathematical model that can describe the dependency between the level of antimicrobial resistance and the amount of antibiotic usage. METHODS: After reviewing existing mathematical models, a cross-sectional, retrospective study was carried out to collect clinical and microbiological data across 3000 patients for the construction of the mathematical model. Based on these data, a model was developed and tested to determine the dependency between antibiotic usage and resistance. RESULTS: Consumption of inhibitor/cephalosporins and fluoroquinolones increases inhibitor/penicillin resistance. Consumption of inhibitor/penicillins increases cephalosporin resistance. Consumption of inhibitor/penicillins increases inhibitor/cephalosporin resistance. CONCLUSIONS: It was demonstrated that in some antibiotic-micro-organism pairs, the level of antibiotic usage significantly influences the level of resistance. The model makes it possible to predict the change in resistance and also shows the quantitative effect of antibiotic consumption on the level of bacterial resistance.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Bacteria/drug effects , Drug Resistance, Bacterial , Drug Utilization , Models, Theoretical , Bacterial Infections/drug therapy , Cross-Sectional Studies , Humans , Retrospective Studies
19.
Biochemistry (Mosc) ; 81(8): 876-83, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27677555

ABSTRACT

Side-by-side with inhibition of the Na+,K+-ATPase ouabain and other cardiotonic steroids (CTS) can affect cell functions by mechanisms other than regulation of the intracellular Na+ and K+ ratio ([Na+]i/[K+]i). Thus, we compared the dose- and time-dependences of the effect of ouabain on intracellular [Na+]i/[K+]i ratio, Na+,K+-ATPase activity, and proliferation of human umbilical vein endothelial cells (HUVEC). Treatment of the cells with 1-3 nM ouabain for 24-72 h decreased the [Na+]i/[K+]i ratio and increased cell proliferation by 20-50%. We discovered that the same ouabain concentrations increased Na+,K+-ATPase activity by 25-30%, as measured by the rate of (86)Rb(+) influx. Higher ouabain concentrations inhibited Na+,K+-ATPase, increased [Na+]i/[K+]i ratio, suppressed cell growth, and caused cell death. When cells were treated with low ouabain concentrations for 48 or 72 h, a negative correlation between [Na+]i/[K+]i ratio and cell growth activation was observed. In cells treated with high ouabain concentrations for 24 h, the [Na+]i/[K+]i ratio correlated positively with proliferation inhibition. These data demonstrate that inhibition of HUVEC proliferation at high CTS concentrations correlates with dissipation of the Na+ and K+ concentration gradients, whereas cell growth stimulation by low CTS doses results from activation of Na+,K+-ATPase and decrease in the [Na+]i/[K+]i ratio.


Subject(s)
Cell Proliferation/drug effects , Human Umbilical Vein Endothelial Cells/metabolism , Ouabain/pharmacology , Potassium/metabolism , Sodium-Potassium-Exchanging ATPase/metabolism , Sodium/metabolism , Cell Death/drug effects , Dose-Response Relationship, Drug , Human Umbilical Vein Endothelial Cells/cytology , Humans , Ion Transport/drug effects
20.
Exp Oncol ; 38(2): 101-7, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27356578

ABSTRACT

UNLABELLED: Within B-cell lineage cell surface receptor CD150/SLAMF1 is broadly expressed starting from pre-B cells with upregulation toward plasma cells. However, expression of CD150 is rather limited on the surface of malignant B cells with the block of differentiation at the different stages of maturation. The aim of our work was to explore CD150 expression both on protein and mRNA levels with the emphasis on CD150 isoforms in malignant B-cell lines at the different stages of maturation in comparison with their normal B cell counterparts. MATERIALS AND METHODS: Studies were performed on normal tonsillar B-cell subpopulations, B-lymphoblastoid cell lines, malignant B-cell lines of different origin, including pre-B acute lymphoblastic leukemia, Burkitt's lymphoma, Hodgkin's lymphoma, and multiple myeloma. Protein CD150 expression was assessed by western blot analysis and the expression level of CD150 isoforms was evaluated using qRT-PCR. RESULTS: Despite the similar CD150 expression both on mRNA and protein levels in normal B-cell subsets and B-lymphoblastoid cell lines, malignant B-cell lines demonstrated substantial heterogeneity in CD150 expression. Only Hodgkin's lymphoma cell lines, Burkitt's lymphoma cell lines BJAB and Raji, and also pre-B cell line BLIN-1 expressed CD150 protein. At the same time total CD150 and mCD150 mRNA was detected in all studied cell lines excluding pre-B cell line REH. The minor sCD150 isoform was found only in Hodgkin's lymphoma cell lines and Burkitt's lymphoma cell line Raji. The nCD150 isoform was broadly expressed in tested B cell lines with exception of REH and Daudi. CONCLUSION: Malignant B-cell lines at the different stages of maturation only partially resemble their normal counterparts by CD150 expression. In malignant B-cell lines, CD150 expression on mRNA level is much broader than on protein level. CD150 isoforms are differentially expressed in normal and malignant B cells with predominant expression of mCD150 isoform.


Subject(s)
B-Lymphocytes/pathology , Burkitt Lymphoma/genetics , Gene Expression Regulation, Neoplastic , Hodgkin Disease/genetics , Multiple Myeloma/genetics , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/genetics , Signaling Lymphocytic Activation Molecule Family Member 1/genetics , B-Lymphocytes/metabolism , Burkitt Lymphoma/pathology , Cell Line , Cell Line, Tumor , Hodgkin Disease/pathology , Humans , Multiple Myeloma/pathology , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/pathology , Protein Isoforms/analysis , Protein Isoforms/genetics , RNA, Messenger/genetics , Signaling Lymphocytic Activation Molecule Family Member 1/analysis
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