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1.
Vestn Oftalmol ; 139(5): 81-88, 2023.
Article in Russian | MEDLINE | ID: mdl-37942601

ABSTRACT

In March 2020 the World Health Organization (WHO) declared a pandemic of the novel coronavirus infection (COVID-19) caused by the SARS-CoV-2 respiratory virus. The high spread rate of the virus and the severity of the course of the disease are of great clinical and epidemiological significance, making it relevant for ophthalmologists to study the mechanisms of how SARS-CoV-2 infects ocular structures, as well as possible clinical manifestations of the infection in the organ of vision. This review contains analysis, systematization, and generalization of epidemiological and clinical data on SARS-CoV-2 ocular lesions and was carried out with the data found in scientific abstract databases. The article presents main clinical ophthalmic manifestations of COVID-19, lists the utilized schemes of etiotropic and symptomatic therapy, recommended preventive measures, and considers the possible ophthalmic complications after vaccination against COVID-19.


Subject(s)
COVID-19 , Humans , SARS-CoV-2 , Eye , Pandemics/prevention & control
2.
Dokl Biol Sci ; 509(1): 116-118, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37208578

ABSTRACT

Gutless marine worms of the family Siboglinidae have been found in the estuaries of the largest Arctic rivers Yenisei, Lena, and Mackenzie. Siboglinid metabolism is provided by symbiotic chemoautotrophic bacteria. Strong salinity stratification is characteristic of the estuaries of the largest Arctic rivers and ensures a high salinity at depths of 25-36 m, where siboglinids were found. High methane concentrations, which are necessary for siboglinid metabolism, result from dissociation of permafrost gas hydrates under the influence of river runoff in the conditions of Arctic warming.


Subject(s)
Annelida , Permafrost , Polychaeta , Animals , Rivers , Estuaries , Arctic Regions
3.
Dokl Biol Sci ; 509(1): 124-127, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37208580

ABSTRACT

Biodiversity in the Laptev Sea was assessed for gutless marine worms of the family Siboglinidae (Annelida), whose metabolism is provided by symbiotic bacteria that oxidize hydrogen sulfide and methane. Seven siboglinid species were found within the geographical boundaries of the Laptev Sea, and another species was found in an adjacent sector of the Arctic Basin. The largest number of finds and the greatest biological diversity of siboglinids were observed in the eastern part of the Laptev Sea in a field of numerous methane flares. One find was made in the estuary area of the Lena River at a depth of 25 m. A possible association of siboglinids with methane seepage areas is discussed.


Subject(s)
Annelida , Polychaeta , Animals , Phylogeny , Methane , Biodiversity
4.
Dokl Biol Sci ; 508(1): 81-84, 2023 Feb.
Article in English | MEDLINE | ID: mdl-37186052

ABSTRACT

Representatives of pogonophorans (Annelida, Siboglinidae), whose vital activity is provided by symbiotic chemoautotrophic bacteria that oxidize methane and hydrogen sulfide, were found in the St. Anna Trough at depths of 539 and 437 m. The finding of pogonophorans suggests high concentrations of methane, which might result from dissociation of bottom gas hydrates under the influence of the influx of warm Atlantic water into the Kara Sea along the St. Anna Trough.


Subject(s)
Annelida , Polychaeta , Animals , Methane , Water , Bacteria
5.
Dokl Biol Sci ; 506(1): 128-131, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36301418

ABSTRACT

The fine structure of the body wall and gut was for the first time studied in the competent larvae of the frenulate pogonophoran Siboglinum fiordicum. Mass apoptosis of cell nuclei was observed in the dermo-muscular body wall and coelomic epithelium. Apoptotic nuclei were found in both cell cytoplasm and outside of the larval body. In the latter case, each nucleus was surrounded by the plasmalemma, and the entire cluster was covered with the cuticle. Cells of the larval gut retained the usual structure with the cytoplasm filled with numerous yolky granules and the nucleus displaying usual morphology. Similar apoptotic processes have been described in vestimentiferans and found to be initiated by penetration of symbiotic bacteria through the integument into the dorsal mesentery. The process of apoptotic rearrangement of body wall cells and the formation of unique symbiosis with bacteria were assumed to be time-spaced in S. fiordicum, occurring sequentially rather than simultaneously, unlike in vestimentiferans.


Subject(s)
Annelida , Polychaeta , Animals , Polychaeta/microbiology , Symbiosis , Bacteria , Apoptosis
6.
Dokl Biol Sci ; 506(1): 150-153, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36301423

ABSTRACT

The article describes the parameters of maintaining the gutless symbiotrophic annelid Siboglinum fiordicum in laboratory conditions outside the marine environment for 64 days.


Subject(s)
Annelida , Polychaeta , Animals , Phylogeny
7.
Dokl Biol Sci ; 502(1): 42-45, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35298753

ABSTRACT

The anatomical and histological structure of the trophosome of the giant vestimentiferan Riftiapachyptila has been studied. The trophosome consists of longitudinally oriented cords. The cords of the trophosome intertwine, form diverticula and anastomose with each other. Each cord has an axial blood vessel inside, which is connected to afferent vessels on the surface of the cord by radial capillaries. Based on the data on the structure and development of the trophosome, it is suggested that the evolutionary precursor of the trophosome was a blood network connecting the ventral and dorsal vessels. The cells of the coelomic lining on the surface of the vessels grew and gave rise to the parenchymal tissue of the trophosome. At the same time, the trophosome developed from two sources, namely: due to the coelomic lining on the surface of the vessels of the intestinal plexus and due to the coelomic lining on the surface of the vessels of the circulatory plexus of the body wall.


Subject(s)
Annelida , Polychaeta , Animals
8.
Dokl Biol Sci ; 501(1): 187-191, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34962604

ABSTRACT

Pogonophora or siboglinid tubeworms (Annelida, Siboglinidae) have been found in the East Siberian Sea for the first time. On the basis of the results of molecular phylogenetic analysis, the found specimens are presumably assigned to the genus Oligobrachia. The stations where the siboglinid tubeworms have been found are located in the area of methane seeps. This confirms the previously stated hypothesis about relationship of siboglinid tubeworm distribution with the areas of underwater methane seeps.


Subject(s)
Annelida , Polychaeta , Animals , Methane , Phylogeny
9.
Phys Rev Lett ; 126(13): 131103, 2021 Apr 02.
Article in English | MEDLINE | ID: mdl-33861094

ABSTRACT

We report on the first subpicometer interferometer flown in space. It was part of ESA's Laser Interferometer Space Antenna (LISA) Pathfinder mission and performed the fundamental measurement of the positional and angular motion of two free-falling test masses. The interferometer worked immediately, stably, and reliably from switch on until the end of the mission with exceptionally low residual noise of 32.0_{-1.7}^{+2.4} fm/sqrt[Hz], significantly better than required. We present an upper limit for the sensor performance at millihertz frequencies and a model for the measured sensitivity above 200 mHz.

10.
Vestn Oftalmol ; 136(5): 103-108, 2020.
Article in Russian | MEDLINE | ID: mdl-33056970

ABSTRACT

Primary open-angle glaucoma is a major cause of irreversible blindness in all countries of the world. The pathogenesis of primary open-angle glaucoma has not been resolved. In addition to increased intraocular pressure, pathogenetic factors of this disease such as reduced systemic blood pressure, deterioration of ocular blood flow, as well as vascular dysregulation, reperfusion damage and oxidative stress of ocular tissues are now generally recognized. The role of α1-adrenoreceptors in regulation of, for example, ocular blood flow, blood flow in the retina, permeability of the vascular wall etc has already been described. PURPOSE: To identify the effects of different subtypes of α1-adrenoreceptors on the level of systemic blood pressure in laboratory mice. MATERIAL AND METHODS: Features of blood pressure of 36 laboratory mice older than 18 months having a genetic defect (lines ADRA-1A, ADRA-1D and ADRA-1D) of one of the subtypes of α1-adrenoreceptors (α1a, α1b, α1d) were studied. The control group included ten healthy laboratory mice of the same age. The blood pressure of mice was measured with modern high-precision and noninvasive method using the CodaTM Standard system (Kent Scientific Corporation, U.S.A.). RESULTS: The mice of the ADRA-1A line were revealed to have reduced systolic and diastolic blood pressure and maximum level of pulse pressure, as well as the greatest fluctuations of pulse pressure; for the ADRA-1B line - the highest levels of systolic and diastolic blood pressure; for the ADRA-1D line - the smallest systolic and diastolic blood pressure and the minimum values of pulse pressure. CONCLUSION: The obtained results show the specific contribution of α1a, α1b and α1d subtypes of the adrenoreceptors in the maintenance of normal hemodynamic of an organism, which should be considered when studying pathogenesis of primary open-angle glaucoma.


Subject(s)
Glaucoma, Open-Angle , Glaucoma , Animals , Blood Pressure , Eye , Glaucoma, Open-Angle/genetics , Mice , Receptors, Adrenergic, alpha-1/genetics
11.
Rev Sci Instrum ; 91(4): 045003, 2020 Apr 01.
Article in English | MEDLINE | ID: mdl-32357757

ABSTRACT

The Laser Interferometer Space Antenna Pathfinder (LPF) main observable, labeled Δg, is the differential force per unit mass acting on the two test masses under free fall conditions after the contribution of all non-gravitational forces has been compensated. At low frequencies, the differential force is compensated by an applied electrostatic actuation force, which then must be subtracted from the measured acceleration to obtain Δg. Any inaccuracy in the actuation force contaminates the residual acceleration. This study investigates the accuracy of the electrostatic actuation system and its impact on the LPF main observable. It is shown that the inaccuracy is mainly caused by the rounding errors in the waveform processing and also by the random error caused by the analog to digital converter random noise in the control loop. Both errors are one order of magnitude smaller than the resolution of the commanded voltages. We developed a simulator based on the LPF design to compute the close-to-reality actuation voltages and, consequently, the resulting actuation forces. The simulator is applied during post-processing the LPF data.

12.
Dokl Biol Sci ; 490(1): 16-18, 2020 Jan.
Article in English | MEDLINE | ID: mdl-32342320

ABSTRACT

We have conducted comparative analysis of the structure of the dorsal lips of the polychaete Eudistylia polymorpha from the family Sabellidae and the obturacula of Oasisia alvinae (Vestimentifera). It has been concluded that the obturacula of Vestimentifera are homologs of the dorsal lips of Polychaete from the family Sabellidae. It has been suggested that the head lobe of siboglinids of the subfamily Frenulata is homologous to the fused obturacula of Vestimentifera.


Subject(s)
Mouth/anatomy & histology , Mouth/physiology , Polychaeta/anatomy & histology , Polychaeta/physiology , Animals , Aquatic Organisms , Polychaeta/cytology
13.
Dokl Biol Sci ; 490(1): 25-27, 2020 Jan.
Article in English | MEDLINE | ID: mdl-32342322

ABSTRACT

Here we report the first finding of a frenulate pogonophoran (Annelida, Siboglinidae) in the southern part of the Kara Sea. This finding was made in the Yenisei Gulf in the region of the highest methane concentrations, resulting from the degradation of permafrost under the influence of river flow. It has been suggested that pogonophorans are indicators of hydrocarbon manifestations of various genesis.


Subject(s)
Annelida/anatomy & histology , Methane/analysis , Animals , Annelida/chemistry , Annelida/physiology , Geologic Sediments , Oceans and Seas , Russia , Seawater/chemistry
14.
Phys Rev Lett ; 123(11): 111101, 2019 Sep 13.
Article in English | MEDLINE | ID: mdl-31573236

ABSTRACT

We report on the results of the LISA Pathfinder (LPF) free-fall mode experiment, in which the control force needed to compensate the quasistatic differential force acting on two test masses is applied intermittently as a series of "impulse" forces lasting a few seconds and separated by roughly 350 s periods of true free fall. This represents an alternative to the normal LPF mode of operation in which this balancing force is applied continuously, with the advantage that the acceleration noise during free fall is measured in the absence of the actuation force, thus eliminating associated noise and force calibration errors. The differential acceleration noise measurement presented here with the free-fall mode agrees with noise measured with the continuous actuation scheme, representing an important and independent confirmation of the LPF result. An additional measurement with larger actuation forces also shows that the technique can be used to eliminate actuation noise when this is a dominant factor.

15.
Dokl Biol Sci ; 485(1): 37-39, 2019 Mar.
Article in English | MEDLINE | ID: mdl-31197591

ABSTRACT

During the growth of hydrothermal vestimentiferan Oasisia alvinae the trunk part of body was found to be elongated (from 51 to 83.4% of the overall body length), while the relative dimensions of all other body regions decreased. This was related to the enhanced trophosome and gonad development in the trunk part. We suppose that predominant trunk growth is a common feature of all vestimentiferans.


Subject(s)
Polychaeta/growth & development , Animals , Gonads/growth & development , Hydrothermal Vents , Polychaeta/anatomy & histology
16.
Adv Gerontol ; 31(1): 95-102, 2018.
Article in Russian | MEDLINE | ID: mdl-29860736

ABSTRACT

The search for new information on the pathogenesis of primary open-angle glaucoma (POAG) is relevant to the whole world, because population aging affects all countries. Also according to the UN prediction by 2030 more than 210 million patients with glaucoma will be officially registered and the same amount of people will not know if they have the disease. Considering the global fundamental problem of aging as a medical and social problem of national importance, it is necessary to make every effort to improve the effectiveness of prevention and pathogenetically-based regenerative therapy of POAG - the world's leading cause of irreversible loss of vision that by saving labor activity of the elderly person will reduce the burden on the state budget. The publication purpose - to consider the main theories of an etiopathogenesis of POAG in close interrelation.


Subject(s)
Glaucoma, Open-Angle/etiology , Aged , Humans
17.
Dokl Biol Sci ; 478(1): 22-25, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29536402

ABSTRACT

Ultrastructural study of the excretory tree of vestimentifera Ridgeia piscesae has shown that it consists of tubules that are blind at their distal ends. The tubules are lined with ciliated cells and have one or two multiciliated terminal cell(s) at the distal ends. In the tubule walls, there are putative ultrafiltration sites. The excretory tree tubules are interpreted as the secondary protonephridia.


Subject(s)
Annelida/ultrastructure , Animals , Annelida/physiology , Nephrons/physiology , Nephrons/ultrastructure
18.
Phys Rev Lett ; 120(6): 061101, 2018 Feb 09.
Article in English | MEDLINE | ID: mdl-29481269

ABSTRACT

In the months since the publication of the first results, the noise performance of LISA Pathfinder has improved because of reduced Brownian noise due to the continued decrease in pressure around the test masses, from a better correction of noninertial effects, and from a better calibration of the electrostatic force actuation. In addition, the availability of numerous long noise measurement runs, during which no perturbation is purposely applied to the test masses, has allowed the measurement of noise with good statistics down to 20 µHz. The Letter presents the measured differential acceleration noise figure, which is at (1.74±0.05) fm s^{-2}/sqrt[Hz] above 2 mHz and (6±1)×10 fm s^{-2}/sqrt[Hz] at 20 µHz, and discusses the physical sources for the measured noise. This performance provides an experimental benchmark demonstrating the ability to realize the low-frequency science potential of the LISA mission, recently selected by the European Space Agency.

19.
Phys Rev Lett ; 118(17): 171101, 2017 Apr 28.
Article in English | MEDLINE | ID: mdl-28498710

ABSTRACT

We report on electrostatic measurements made on board the European Space Agency mission LISA Pathfinder. Detailed measurements of the charge-induced electrostatic forces exerted on free-falling test masses (TMs) inside the capacitive gravitational reference sensor are the first made in a relevant environment for a space-based gravitational wave detector. Employing a combination of charge control and electric-field compensation, we show that the level of charge-induced acceleration noise on a single TM can be maintained at a level close to 1.0 fm s^{-2} Hz^{-1/2} across the 0.1-100 mHz frequency band that is crucial to an observatory such as the Laser Interferometer Space Antenna (LISA). Using dedicated measurements that detect these effects in the differential acceleration between the two test masses, we resolve the stochastic nature of the TM charge buildup due to interplanetary cosmic rays and the TM charge-to-force coupling through stray electric fields in the sensor. All our measurements are in good agreement with predictions based on a relatively simple electrostatic model of the LISA Pathfinder instrument.

20.
Antibiot Khimioter ; 60(3-4): 20-3, 2015.
Article in Russian | MEDLINE | ID: mdl-26415379

ABSTRACT

The data on inhibition of the growth of microorganisms of a characteristic spectrum and antibiotic resistance isolated from long-term healing wounds by light of various wave ranges are presented. The growing cultures on blood agar were exposed to polarized light, red and infrared, ultraviolet of medium- and short-wave continuous modes accustomed in physiotherapy of wounds.The effect of light in some way induced inhibition of the growth, but complete recovery was stated only after the use of ultraviolet light when confirmed quantitatively in terms of the CFU.


Subject(s)
Candida/radiation effects , Gram-Negative Bacteria/radiation effects , Gram-Positive Bacteria/radiation effects , Ultraviolet Therapy/methods , Anti-Bacterial Agents/pharmacology , Candida/drug effects , Candida/growth & development , Candida/isolation & purification , Colony Count, Microbial , Culture Media/chemistry , Gram-Negative Bacteria/drug effects , Gram-Negative Bacteria/growth & development , Gram-Negative Bacteria/isolation & purification , Gram-Positive Bacteria/drug effects , Gram-Positive Bacteria/growth & development , Gram-Positive Bacteria/isolation & purification , Humans , Infrared Rays , Ultraviolet Rays , Wound Healing/drug effects , Wound Healing/physiology , Wound Healing/radiation effects , Wounds and Injuries/drug therapy , Wounds and Injuries/microbiology , Wounds and Injuries/radiotherapy
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