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1.
Sci Rep ; 12(1): 21701, 2022 Dec 15.
Article in English | MEDLINE | ID: mdl-36522483

ABSTRACT

With the help of numerical simulation, a detailed analysis of the dynamical effect of the stratospheric quasi-biennial oscillation (QBO) of the equatorial zonal wind on the planetary waves (PWs) up to thermospheric heights is carried out for the first time. The 3-dimensional nonlinear mechanistic model of middle and upper atmosphere (MUAM) is used, which is capable of simulating the general atmospheric circulation from the surface up to 300-400 km altitude. The amplitudes of stationary and westward travelling PWs with periods from 4 to 10 days are calculated based on ensembles of model simulations for conditions corresponding to the easterly and westerly QBO phases. Fluxes of wave activity and refractive indices of the atmosphere are calculated to analyze the detailed behavior of the PWs. The important result to emerge is that the stratospheric QBO causes statistically significant changes in the amplitudes of individual wave components up to 25% in the mesosphere-lower thermosphere and 10% changes above 200 km. This change in wave structures should be especially noticeable in the atmosphere during periods of low solar activity, when the direct contribution of solar activity fluctuations is minimized. Propagating from the troposphere to the upper atmosphere, PWs contribute to the propagation of the QBO signal not only from the equatorial region to extratropical latitudes, but also from the stratosphere to the thermosphere. The need for a detailed analysis of large-scale wave disturbances in the upper atmosphere and their relationship with the underlying layers is due, in particular, to their significant impact on satellite navigation and communication systems, which is caused by amplitude and phase fluctuations of the radio signal.

2.
Geophys Res Lett ; 49(9): e2021GL096986, 2022 May 16.
Article in English | MEDLINE | ID: mdl-35864893

ABSTRACT

We report observations of reconnection exhausts in the Heliospheric Current Sheet (HCS) during Parker Solar Probe Encounters 08 and 07, at 16 R s and 20 R s , respectively. Heliospheric current sheet (HCS) reconnection accelerated protons to almost twice the solar wind speed and increased the proton core energy by a factor of ∼3, due to the Alfvén speed being comparable to the solar wind flow speed at these near-Sun distances. Furthermore, protons were energized to super-thermal energies. During E08, energized protons were found to have leaked out of the exhaust along separatrix field lines, appearing as field-aligned energetic proton beams in a broad region outside the HCS. Concurrent dropouts of strahl electrons, indicating disconnection from the Sun, provide further evidence for the HCS being the source of the beams. Around the HCS in E07, there were also proton beams but without electron strahl dropouts, indicating that their origin was not the local HCS reconnection exhaust.

3.
Vavilovskii Zhurnal Genet Selektsii ; 26(3): 240-249, 2022 May.
Article in English | MEDLINE | ID: mdl-35774365

ABSTRACT

Recombinant chymosins (rСhns) of the cow and the camel are currently considered as standard milk coagulants for cheese-making. The search for a new type of milk-clotting enzymes that may exist in nature and can surpass the existing "cheese-making" standards is an urgent biotechnological task. Within this study, we for the first time constructed an expression vector allowing production of a recombinant analog of moose chymosin in the expression system of Escherichia coli (strain SHuffle express). We built a model of the spatial structure of moose chymosin and compared the topography of positive and negative surface charges with the correspondent structures of cow and camel chymosins. We found that the distribution of charges on the surface of moose chymosin has common features with that of cow and camel chymosins. However, the moose enzyme carries a unique positively charged patch, which is likely to affect its interaction with the substrate. Biochemical and technological properties of the moose rChn were studied. Commercial rСhns of cow and camel were used as comparison enzymes. In some technological parameters, the moose rChn proved to be superior to the reference enzymes. Сompared with the cow and camel rСhns, the moose chymosin specific activity is less dependent on the changes in CaCl2 concentration in the range of 1-5 mM and pH in the range of 6-7, which is an attractive technological property. The total proteolytic activity of the moose rСhn occupies an intermediate position between the rСhns of cow and camel. The combination of biochemical and technological properties of the moose rСhn argues for further study of this enzyme.

4.
Geophys Res Lett ; 48(11): e2021GL092700, 2021 Jun 16.
Article in English | MEDLINE | ID: mdl-34219832

ABSTRACT

A sequence of discrete solar wind structures within the sheath region of an interplanetary coronal mass ejection on November 6, 2015, caused a series of compressions and releases of the dayside magnetosphere. Each compression resulted in a brief adiabatic enhancement of ions (electrons) driving bursts of electromagnetic ion cyclotron (EMIC; whistler mode chorus) wave growth across the dayside magnetosphere. Fine-structured rising tones were observed in the EMIC wave bursts, resulting in nonlinear scattering of relativistic electrons in the outer radiation belt. Multipoint observations allow us to study the spatial structure and evolution of these sheath structures as they propagate Earthward from L1 as well as the spatio-temporal characteristics of the magnetospheric response. This event highlights the importance of fine-scale solar wind structure, in particular within complex sheath regions, in driving dayside phenomena within the inner magnetosphere.

5.
Mol Biol (Mosk) ; 52(6): 1038-1044, 2018.
Article in Russian | MEDLINE | ID: mdl-30633246

ABSTRACT

The functions of small noncoding RNAs 4.5SH and 4.5SI found in murine-like rodents are unclear. These RNAs synthesized by RNA polymerase III are widely expressed in rodent organs and tissues. Using crosslinking assays, it was shown that approximately half of all 4.5SI and 4.5SH RNA molecules were bound to proteins provisionally called X and Y, respectively. An immunoprecipitation experiment showed that both these RNAs were associated with the La protein, which did not crosslink to them. The termini of 4.5SI RNA form a long duplex stem, which makes the molecule more stable than 4.5SH RNA. Modification of the 5'-end sequence destructing the stem of 4.5SI RNA altered its protein-binding properties; after the 3'-end sequence was changed to the complementary, both the stem structure and the RNA binding to protein X were restored. Presumably, this protein plays a role in increasing the half-life of 4.5SI RNA.


Subject(s)
Protein Binding , RNA, Bacterial/genetics , RNA, Small Untranslated/genetics , Animals , Nucleic Acid Conformation , Rodentia
6.
Kardiologiia ; 57(S1): 367-372, 2017.
Article in Russian | MEDLINE | ID: mdl-29276910

ABSTRACT

The article presents a case report of metastatic heart damage which developed in association with urothelial bladder carcinoma in a 79-year old female patient. Various masses may be found in the heart. In tumors, a secondary damage to the heart is observed much more frequently than a primary damage; however, metastasis of bladder carcinoma to the heart is extremely rare. Of interest is the fact of metastatic damage to all layers of the heart, including the endocardium, pericardium, and myocardium.


Subject(s)
Carcinoma, Transitional Cell/secondary , Heart Neoplasms/secondary , Urinary Bladder Neoplasms/pathology , Aged , Carcinoma, Transitional Cell/physiopathology , Fatal Outcome , Female , Heart Neoplasms/physiopathology , Humans , Urinary Bladder Neoplasms/physiopathology
7.
Mol Biol (Mosk) ; 51(1): 142-149, 2017.
Article in Russian | MEDLINE | ID: mdl-28251977

ABSTRACT

Studying the structure, functions, and cell physiology of small RNAs remains important. The 4.5SI and 4.5SH small RNAs, which were among the first to be discovered and sequenced, share several features, i.e., they are both approximately 100 nt in size, are synthesized by RNA polymerase III, and are found only in rodents of several related families. Genes coding for these RNAs are evolutionarily related to short interspersed elements (SINEs). However, the two RNAs differ in nucleotide sequence, half-life in the cell, and the organization of their genes in the genome. Although the 4.5SI and 4.5SH RNAs have been identified more than three decades ago, several aspects of their metabolism in the cell are still poorly understood. The 4.5SI and 4.5SH RNA levels were measured in various organs of three rodent species (mouse, rat, and hamster). Both of the RNAs were found to occur at high levels, which were much the same in different organs in the case of the 4.5SI RNA and varied among organs in the case of the 4.5SH RNA. Both 4.5SI and 4.5SH RNAs demonstrated a predominantly nuclear localization with a detectable presence in the cytoplasm. The copy number per cell for the RNAs was estimated at 0.4-2.4 × 10^(6). A quantitative study for the 4.5SI and 4.5SH RNAs was performed for the first time and resolved a number of contradictions in data from other studies.


Subject(s)
RNA, Bacterial/genetics , Rodentia , Animals , Cricetinae , Gene Dosage , Genome , Mice , Rats , Tissue Distribution
8.
J Geophys Res Space Phys ; 122(9): 9115-9133, 2017 Sep.
Article in English | MEDLINE | ID: mdl-30410850

ABSTRACT

A study of the structure of 145 low-Mach number (M ≤ 3), low-beta (ß ≤ 1), quasi-perpendicular interplanetary collisionless shock waves observed by the Wind spacecraft has provided strong evidence that these shocks have large-amplitude whistler precursors. The common occurrence and large amplitudes of the precursors raise doubts about the standard assumption that such shocks can be classified as laminar structures. This directly contradicts standard models. In 113 of the 145 shocks (~78%), we observe clear evidence of magnetosonic-whistler precursor fluctuations with frequencies ~0.1-7 Hz. We find no dependence on the upstream plasma beta, or any other shock parameter, for the presence or absence of precursors. The majority (~66%) of the precursors propagate at ≤45° with respect to the upstream average magnetic field and most (~87%) propagate ≥30° from the shock normal vector. Further, most (~79%) of the waves propagate at least 20° from the coplanarity plane. The peak-to-peak wave amplitudes (δB pk-pk) are large with a range of maximum values for the 113 precursors of ~0.4-13 nT with an average of ~2 nT. When we normalize the wave amplitudes to the upstream averaged magnetic field and the shock ramp amplitude, we find average values of ~40% and ~220%, respectively.

9.
Fiziol Cheloveka ; 42(1): 40-51, 2016.
Article in Russian | MEDLINE | ID: mdl-27188146

ABSTRACT

The article presents the results of classification of EEG patterns registered during imagined rhytmic movements of the fingers of the right hand (little, thumb, index, middle fingers) in 8 healthy subjects. The subjects imagined finger movements in a given rhythm; no external stimuli were used. A two-level committee of classifiers was developed for decoding: the first level included support vector machines and artificial neural networks; the second level included artificial neural network used for generalizing. As the key parameters for classification, we used the area of zone under the envelope of EEG signal and the length of the envelope calculated in sliding time window for leads F3, C3 and Cz in system 10-20 were chosen as the key features for signals of sensorimotor and adjoining frontal area cortex contralateral to movements. The accuracy of classification of single trials for 4 movements averaged for all subjects for the pair of leads F3-C3 was 50 ± 7% [SD] (maximal - 58%); for the pair of leads C3-Cz, 46 ± 11% [SD] (maximal - 62%); theoretical guessing level is 25%.


Subject(s)
Electroencephalography , Fingers/physiology , Movement , Hand , Humans , Neural Networks, Computer , Support Vector Machine
10.
Biochem Pharmacol ; 87(4): 571-8, 2014 Feb 15.
Article in English | MEDLINE | ID: mdl-24355563

ABSTRACT

Research on existing drugs often discovers novel mechanisms of their action and leads to the expansion of their therapeutic scope and subsequent remarketing. The Wnt signaling pathway is of the immediate therapeutic relevance, as it plays critical roles in cancer development and progression. However, drugs which disrupt this pathway are unavailable despite the high demand. Here we report an attempt to identify antagonists of the Wnt-FZD interaction among the library of the FDA-approved drugs. We performed an in silico screening which brought up several potential antagonists of the ligand-receptor interaction. 14 of these substances were tested using the TopFlash luciferase reporter assay and four of them identified as active and specific inhibitors of the Wnt3a-induced signaling. However, further analysis through GTP-binding and ß-catenin stabilization assays showed that the compounds do not target the Wnt-FZD pair, but inhibit the signaling at downstream levels. We further describe the previously unknown inhibitory activity of an anti-leprosy drug clofazimine in the Wnt pathway and provide data demonstrating its efficiency in suppressing growth of Wnt-dependent triple-negative breast cancer cells. These data provide a basis for further investigations of the efficiency of clofazimine in treatment of Wnt-dependent cancers.


Subject(s)
Clofazimine/pharmacology , Growth Inhibitors/pharmacology , Leprostatic Agents/pharmacology , Triple Negative Breast Neoplasms/pathology , Wnt Signaling Pathway/drug effects , Wnt Signaling Pathway/physiology , Wnt3A Protein/antagonists & inhibitors , Wnt3A Protein/physiology , Animals , Binding Sites/drug effects , Binding Sites/physiology , Cell Line, Tumor , Clofazimine/therapeutic use , Crystallography, X-Ray , Growth Inhibitors/therapeutic use , HEK293 Cells , Humans , Leprostatic Agents/therapeutic use , Mice , Triple Negative Breast Neoplasms/chemistry , Triple Negative Breast Neoplasms/drug therapy , Wnt3A Protein/chemistry
12.
Bioorg Khim ; 34(3): 327-32, 2008.
Article in Russian | MEDLINE | ID: mdl-18672680

ABSTRACT

Genes of human neurotrophins NGF, BDNF, NT-3 were cloned, and the corresponding proteins and their fragments were expressed in Escherichia coli BL-21 (DE3lambda) cells. Their intracellular localization was determined. The conditions for isolation and purification of the target recombinant proteins and for folding of BDNF and NT-3 precursors were selected. The recombinant proprecursors of human neurotrophines have been shown to possess complex oligomeric structure.


Subject(s)
Brain-Derived Neurotrophic Factor/chemistry , Escherichia coli/metabolism , Nerve Growth Factor/chemistry , Neurotrophin 3/chemistry , Biopolymers , Brain-Derived Neurotrophic Factor/biosynthesis , Brain-Derived Neurotrophic Factor/genetics , Cloning, Molecular , Escherichia coli/genetics , Humans , Nerve Growth Factor/biosynthesis , Nerve Growth Factor/genetics , Neurotrophin 3/biosynthesis , Neurotrophin 3/genetics , Peptide Fragments/biosynthesis , Peptide Fragments/chemistry , Peptide Fragments/genetics , Protein Denaturation , Protein Folding , Protein Precursors/biosynthesis , Protein Precursors/chemistry , Protein Precursors/genetics , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Recombinant Proteins/genetics
13.
Med Parazitol (Mosk) ; (2): 15-7, 2008.
Article in Russian | MEDLINE | ID: mdl-18557358

ABSTRACT

The paper describes the 2003-2004 outbreak oft richinosis in 2 districts of the Kherson Region. Pork was a source of infection. The disease occurred with the ingestion ofshashlik, raw meat, lard, or minced meat. The diagnosis of trichinosis was established 1-1.5 months after the onset of the disease. The patients received a course of therapy and were discharged in a satisfactory condition. The members of their families were prophylactically treated. Meats were bought at the markets and had negative veterinary sanitary tests. A package of antiepidemic and antiepizootic measures was implemented in the foci of trichinosis.


Subject(s)
Disease Outbreaks , Swine/parasitology , Trichinellosis/epidemiology , Animals , Antinematodal Agents/therapeutic use , Communicable Disease Control/standards , Contact Tracing , Humans , Meat Products/parasitology , Mebendazole/therapeutic use , Trichinellosis/drug therapy , Ukraine/epidemiology
14.
Aging Male ; 11(2): 57-61, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18570056

ABSTRACT

INTRODUCTION: Elderly men are bothered by lower urinary tract complaints designated as lower urinary tract symptoms (LUTS). In epidemiological studies LUTS appears strongly associated with erectile dysfunction, and also with metabolic syndrome. LUTS occurs at an age at which plasma testosterone levels decline, in some men to hypogonadal values. Objectives. This pilot study tested whether testosterone administration to elderly men complaining of LUTS and whose plasma testosterone levels are below normal, might alleviate LUTS. METHODS: Group 1 (n = 10) received treatment with testosterone gel (50 mg) daily for three months; group 2 (n = 20) received treatment with injections of testosterone undecanoate 1000 mg for 26 weeks. RESULTS: Upon these interventions, plasma testosterone increased to the normal range. Symptoms of LUTS, measured by the International Prostate Symptoms Score, improved significantly, and also scores of the Aging Males' Symptoms scale and international index of erectile function improved. There were no untoward effects on the prostate over this period of time of the study. CONCLUSION: Testosterone administration improved symptoms of LUTS in men with late-onset hypogonadism. The mechanism of action is as yet not understood, but it may be connected with or parallel with the effects of testosterone on penile tissues in hypogonadal men, such as on nitric oxide and phosphodiesterase.


Subject(s)
Testosterone/pharmacology , Urination Disorders/drug therapy , Adult , Age of Onset , Aged , Aging , Humans , Hypogonadism , Male , Men , Middle Aged , Pilot Projects , Testosterone/administration & dosage , Testosterone/blood , Testosterone/deficiency , Treatment Outcome
15.
Vopr Pitan ; 77(1): 26-9, 2008.
Article in Russian | MEDLINE | ID: mdl-18368847

ABSTRACT

In the experiment on albino male mongrel rats some parameters of oxidative phosphorylation of spleen slices were studied after the animals were fed the antioxidant complex of vitamins E, A, and C. The stimulation of oxygen consumption rate and of tissue respiration of spleen was observed with endogenous substrates, and after exogenous substrates (succinate and glutamate) were added. After the ingestion of vegetable oil the uncoupling of oxidative phosphorylation was observed. The perspectives of alimentary and medicine immunocorrection by the influence upon the mitochondrial oxidation system of cell immune competence organ discussed.


Subject(s)
Antioxidants/pharmacology , Ascorbic Acid/pharmacology , Lymphocytes/metabolism , Oxygen Consumption/drug effects , Spleen/metabolism , Vitamin A/pharmacology , Vitamin E/pharmacology , Animals , Lymphocytes/cytology , Male , Oxidative Phosphorylation/drug effects , Plant Oils/pharmacology , Rats , Spleen/cytology
18.
Urologiia ; (5): 34-6, 2004.
Article in Russian | MEDLINE | ID: mdl-15560159

ABSTRACT

There are three directions in pathogenetic treatment of chronic prostatitis (CP) which is conducted in parallel to etiotropic one (antimicrobial): general immunological; improving arterial inflow and venous outflow; creation of prostatic secretion outflow and that of seminal vesicles by means of contractions of the pelvic and perineal muscles, muscular fibers of the prostatic gland. The latter two directions can be managed with physiotherapy. It is proposed to use combination of drugs with physiotherapy conducted by means of the devices [see text].


Subject(s)
Erectile Dysfunction/therapy , Laser Therapy , Physical Therapy Modalities , Prostatitis/therapy , Adult , Chronic Disease , Combined Modality Therapy , Electric Stimulation Therapy , Erectile Dysfunction/etiology , Erectile Dysfunction/radiotherapy , Humans , Male , Massage , Middle Aged , Prostatitis/complications , Prostatitis/radiotherapy , Vacuum
19.
Urologiia ; (4): 51-5, 2004.
Article in Russian | MEDLINE | ID: mdl-15457956

ABSTRACT

Experiments on 40 white rats were made to study effects of cardura (doxasozine) and viagra on polysystemic energy metabolism in stress. All the animals were examined for cytochemical activity of succinate dehydrogenase, lactate dehydrogenase in blood lymphocytes, antioxidant activity of blood plasm, levels of hydroperoxides, malonic dialdehyde. 3-hour immobilization raises functional activity of mitochondria manifesting with intensification of energy metabolism. Adrenoreceptors blockade by cardura prevents changes in the cellular metabolism. The same antistress effect is observed in viagra action. This newly discovered mechanism may prevent complications of adrenergic reactions accompanying sexual intercourse.


Subject(s)
Energy Metabolism/drug effects , Phosphodiesterase Inhibitors/pharmacology , Piperazines/pharmacology , Stress, Physiological/metabolism , Animals , Doxazosin/pharmacology , L-Lactate Dehydrogenase/analysis , Lymphocytes/enzymology , Lymphocytes/metabolism , Male , Purines , Rats , Sildenafil Citrate , Stress, Physiological/enzymology , Succinate Dehydrogenase/analysis , Sulfones
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