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1.
Dokl Biochem Biophys ; 508(1): 6-11, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36653586

RESUMEN

The effect of PARP1 knockout in HEK293 cells on the gene expression of DNA base excision repair (BER) proteins was studied. It was shown that the expression of all differentially expressed genes (DEGs) of BER was reduced by knockout. The expression of the DNA glycosylase gene NEIL1, which is considered to be one of the common "hubs" for binding BER proteins, has changed the most. The expression of genes of auxiliary subunits of DNA polymerases δ and ε is also significantly reduced. The PARP1 gene knockout cell line obtained is an adequate cell model for studying the activity of the BER process in the absence of PARP1 and testing drugs aimed at inhibiting repair processes. It has been found for the first time that knockout of the PARP1 gene results in a significant change in the level of expression of proteins responsible for ribosome biogenesis and the functioning of the proteasome.


Asunto(s)
ADN Glicosilasas , Poli(ADP-Ribosa) Polimerasas , Humanos , Poli(ADP-Ribosa) Polimerasas/genética , Células HEK293 , Técnicas de Inactivación de Genes , Reparación del ADN , ADN , ADN Glicosilasas/genética , ADN Glicosilasas/metabolismo , Poli(ADP-Ribosa) Polimerasa-1/genética , Poli(ADP-Ribosa) Polimerasa-1/metabolismo
2.
Vavilovskii Zhurnal Genet Selektsii ; 27(8): 980-987, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38239962

RESUMEN

Many crops require not only leaf photosynthesis for their seed development but also the photochemical reactions that occur in the seeds. The purpose of this work was a comparative analysis of light transmittance and photochemical activity in the leaves of Pisum sativum L. and its pericarp, seed coat, and cotyledons at the early, middle, and late maturation stages. The spectral composition of light was measured using a spectroradiometer in the range of 390-760 nm. We assessed the light transmittance of plant tissues by placing the plant tissue between the light source and the spectroradiometer's sensor. PAM fluorometry was used to quantify the photochemical activity in plant tissues: this technique is handy for evaluating the efficiency of converting light energy into chemical energy through the analysis of the kinetics of chlorophyll fluorescence excitation and quenching. On average, a photochemically active green leaf of pea transmitted 15 % of solar radiation in the 390-760 nm, blue light was delayed entirely, and the transmitted red light never exceeded 5 %. Photochemically active radiation passing through the pericarp and coat and reaching the cotyledons at the early and middle seed maturation stages manifested a high proportion of green and far-red light; there was no blue light, and the percentage of red light was about 2 %. However, the cotyledons were photochemically active regardless of low irradiance and spectral ranges untypical of leaf photosynthesis. At the early and middle maturation stages, the maximum quantum yield of photosystem II (Fv/Fm) averaged 0.5 at the periphery of cotyledons and 0.3 at their center. Since the intensity of embryonic photochemical reactions significantly affects the efficiency of reserve nutrient accumulation, this parameter is a promising marker in pea breeding for seeds with improved nutritional qualities.

3.
Int J Psychophysiol ; 181: 112-124, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36057406

RESUMEN

Thousand-year-old Buddhist traditions have developed a wide range of methods for the subjective exploration of consciousness through meditation. Combining their subjective research with the possibilities of modern neuroscience can help us better understand the physiological mechanisms of consciousness. Therefore, we have been guided by specifically Buddhist explanations when studying the physiological mechanisms of altered states of consciousness during Buddhist meditations. In Buddhism, meditations are generally divided into two large categories: (1) one-pointed concentration and (2) analytical meditation. Maintaining both one-pointed concentration and analytical meditation on 'bodhicitta' ("the thought of awakening") and 'emptiness' is a necessary condition for transitioning into tantric practices. Tantric practices involve sophisticated visualizations of Buddhist deities, the 'energy structure' of the human body, and the visualization of the stage-by-stage process of dying accompanied with the dissolution of body elements. According to Buddhism, these meditations are characterized by the gradual withdrawal from "gross levels" of consciousness associated with the five senses. From a psychophysiological perspective, this withdrawal of sensory consciousness can be considered as the decrease of sensory stimuli recognition and attentional disengagement from the external world. We concentrated on how considered meditations affect sensory and cognitive processing of external stimuli. Auditory event-related potentials (ERPs) in the passive oddball paradigm were studied both during meditations and in a controlled state of relaxed wakefulness. It was shown with a group of 115 Buddhist monks that during meditation, mismatch negativity amplitudes, amplitudes of N1 and P2 components of ERPs to deviant stimuli, and the amplitudes of the P3a component to novel stimuli all decrease. These outcomes suggest that the considered Buddhist meditations, compared to the control state of relaxed wakefulness, are accompanied by a decrease in physiological processes responsible for maintaining attention on the outside world and recognizing changes in the stream of sensory stimuli.


Asunto(s)
Meditación , Monjes , Atención/fisiología , Budismo/psicología , Potenciales Evocados , Humanos , Meditación/métodos
4.
Phys Rev Lett ; 125(18): 186401, 2020 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-33196259

RESUMEN

The coexistence of charge density wave (CDW) and superconductivity in tantalum disulfide (2H-TaS_{2}) at low temperature is boosted by applying hydrostatic pressures to study both vibrational and magnetic transport properties. Around P_{c}, we observe a superconducting dome with a maximum superconducting transition temperature T_{c}=9.1 K. First-principles calculations of the electronic structure predict that, under ambient conditions, the undistorted structure is characterized by a phonon instability at finite momentum close to the experimental CDW wave vector. Upon compression, this instability is found to disappear, indicating the suppression of CDW order. The calculations reveal an electronic topological transition (ETT), which occurs before the suppression of the phonon instability, suggesting that the ETT alone is not directly causing the structural change in the system. The temperature dependence of the first vortex penetration field has been experimentally obtained by two independent methods. While a d wave and single-gap BCS prediction cannot describe the lower critical field H_{c1} data, the temperature dependence of the H_{c1} can be well described by a single-gap anisotropic s-wave order parameter.

5.
Stem Cell Res ; 48: 101952, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32805537

RESUMEN

ICGi021-A and ICGi022-A iPSC lines were obtained by reprogramming PBMCs of two healthy women of the Siberian population using episomal non-integrating vectors expressing Yamanaka factors. iPSC lines expressed pluripotency markers, had a normal karyotype and demonstrated the ability to differentiate into derivatives of the three germ layers. Clinical exome sequencing data of the original biosamples of the donors are available in the NCBI SRA database. The generated cell lines are useful as "healthy" control in biomedical studies.


Asunto(s)
Células Madre Pluripotentes Inducidas , Leucocitos Mononucleares , Diferenciación Celular , Línea Celular , Reprogramación Celular , Femenino , Estratos Germinativos , Humanos , Siberia
6.
Sci Rep ; 10(1): 11282, 2020 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-32647208

RESUMEN

A comprehensive analysis of the state of air inside an industrial workshop with electroplating production was carried out. The data of quantitative distribution of suspended particles by size fractions (PM0.3, PM0.5, PM1, PM3, PM5, PM10) are presented for 15 main processes of electroplating. Morphometric and chemical composition of the surface of particles were studied. We observed particles of rounded shape, various agglomerates with complex geometric shapes, acute-angular particles, which when inhaled pose a maximum threat to human health. Chemical analysis of these particles showed an absolute predominance of oxides of non-ferrous metals, the percentage of which varied depending on the type of electroplating bath. The content of highly hazardous substances of the 1st (Zn, Pb, and Cd) and the 2nd (Cu, Cr, Ni, Co, and Mo) hazard classes in each sample was recorded.

7.
Adv Exp Med Biol ; 1241: 195-217, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32383122

RESUMEN

Amyotrophic lateral sclerosis (ALS) is one of the most common neurodegenerative diseases, characterized by inevitable progressive paralysis. To date, only two disease modifying therapeutic options are available for the patients with ALS, although they show very modest effect on disease course. The main reason of failure in the field of pharmacological correction of ALS is inability to untangle complex relationships taking place during ALS initiation and progression. Traditional methods of research, based on morphology or transgenic animal models studying provided lots of information about ALS throughout the years. However, translation of these results to humans was unsuccessful due to incomplete recapitulation of molecular pathology and overall inadequacy of the models used in the research.In this review we summarize current knowledge regarding ALS molecular pathology with depiction of novel methods applied recently for the studies. Furthermore we describe present and potential treatment strategies that are based on the recent findings in ALS disease mechanisms.


Asunto(s)
Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Esclerosis Amiotrófica Lateral/metabolismo , Esclerosis Amiotrófica Lateral/patología , Animales , Investigación Biomédica , Progresión de la Enfermedad , Humanos
8.
Stem Cell Res ; 42: 101675, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31830646

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by death of motor neurons. To date, neither etiology nor pathogenesis of ALS are known, which leads to the absence of an effective treatment strategy. ALS patient-specific induced pluripotent stem cells (iPSCs) represent an excellent tool for the disease study. We obtained iPSCs line from peripheral blood mononuclear cells of the patient with homozygous Asp90Ala mutation in the SOD1 gene using non-integrating episomal vectors. The iPSCs line retained pathological genotype and expressed pluripotency markers. It also displayed a normal karyotype and the ability to differentiate into derivatives of three germ layers.


Asunto(s)
Esclerosis Amiotrófica Lateral/genética , Reprogramación Celular/genética , Células Madre Pluripotentes Inducidas/metabolismo , Leucocitos Mononucleares/metabolismo , Superóxido Dismutasa-1/genética , Animales , Humanos , Mutación
9.
Stem Cell Res ; 41: 101652, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31733442

RESUMEN

Studying Parkinson's disease (PD), one of the most common neurodegenerative disorders worldwide, requires different model systems, including patient-specific induced pluripotent stem cell lines. With the help of non-integrating episomal vectors the iPSC lines ICGi015-A and ICGi015-B were generated from blood mononuclear cells of PD patient, carrying three SNPs, associated with PD development. The obtained iPSC lines express pluripotency markers and demonstrate the ability to in vitro differentiate into the three germ layers. These cell lines may be useful for studying molecular mechanisms of PD and for drug screening.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Línea Celular/patología , Reprogramación Celular , Células Madre Pluripotentes Inducidas/patología , Leucocitos Mononucleares/patología , Enfermedad de Parkinson/sangre , Enfermedad de Parkinson/patología , Femenino , Humanos , Persona de Mediana Edad
10.
Biochemistry (Mosc) ; 84(3): 291-298, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31221067

RESUMEN

Generation of patient-specific induced pluripotent stem cells (iPSCs) and their subsequent differentiation into cardiomyocytes opened new opportunities for studying pathogenesis of inherited cardiovascular diseases. One of these diseases is hypertrophic cardiomyopathy (HCM) for which no efficient therapy methods have been developed so far. In this study, the approach based on patient-specific iPSCs was applied to create a model of the disease. Genetic analysis of a hypertrophic cardiomyopathy patient revealed R326Q mutation in the MYBPC3 gene. iPSCs of the patient were generated and characterized. The cells were differentiated into cardiomyocytes together with the control iPSCs from a healthy donor. The patient's iPSC-derived cardiomyocytes exhibited early HCM features, such as abnormal calcium handling and increased intracellular calcium concentration. Therefore, cardiomyocytes obtained by directed differentiation of iPSCs from the HCM patient can be used as a model system to study HCM pathogenesis.


Asunto(s)
Cardiomiopatía Hipertrófica/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Modelos Biológicos , Adulto , Calcio/metabolismo , Cardiomiopatía Hipertrófica/diagnóstico , Cardiomiopatía Hipertrófica/genética , Diferenciación Celular , Células Cultivadas , Humanos , Células Madre Pluripotentes Inducidas/patología , Masculino
11.
Biochemistry (Mosc) ; 84(3): 299-309, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31221068

RESUMEN

Patient-specific induced pluripotent stem cells (iPSCs) capable of differentiation into required cell type are a promising model for studying various pathological processes and development of new therapeutic approaches. However, no conventional strategies for using iPSCs in disease research have been established yet. Genetically encoded biosensors can be used for monitoring messenger molecules, metabolites, and enzyme activity in real time with the following conversion of the registered signals in quantitative data, thus allowing evaluation of the impact of certain molecules on pathology development. In this article, we describe the development of a universal cell-based platform for studying pathological processes associated with amyotrophic lateral sclerosis. For this purpose, we have created a series of plasmid constructs for monitoring endoplasmic reticulum stress, oxidative stress, apoptosis, and Ca2+-dependent hyperexcitability and generated transgenic iPSC line carrying mutation in the superoxide dismutase 1 gene (SOD1) and healthy control cell line. Both cell lines have specific transactivator sequence required for doxycycline-controlled transcriptional activation and can be used for a single-step biosensor insertion.


Asunto(s)
Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/patología , Técnicas Biosensibles/métodos , Células Madre Pluripotentes Inducidas/metabolismo , Apoptosis , Calcio/metabolismo , Diferenciación Celular , Células Cultivadas , Estrés del Retículo Endoplásmico , Humanos , Células Madre Pluripotentes Inducidas/patología , Mutación , Estrés Oxidativo , Superóxido Dismutasa-1/genética , Superóxido Dismutasa-1/metabolismo
12.
Phys Rev Lett ; 122(15): 153901, 2019 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-31050515

RESUMEN

Using the cubic Ginzburg-Landau equation as an example, we demonstrate how the inverse scattering transform can be applied to characterize coherent structures in dissipative nonlinear systems. Using this approach one can reduce the number of the effective degrees of freedom in the system when the dynamic is dominated by the coherent structures, even if they are embedded in the dispersive waves and demonstrate unstable behavior.

13.
Stem Cell Res ; 36: 101415, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30851551

RESUMEN

The induced pluripotent stem cell (iPSC) lines ICGi008-A and ICGi008-B were generated from dermal fibroblasts using episomal vectors expressing pluripotency factors. Dermal fibroblasts were obtained from a 55 year old male Сaucasian familial Alzheimer's disease (AD) patient carrying heterozygous V717I mutation in the APP gene. The generated iPSC lines maintained the original APP genotype, expressed pluripotency markers, exhibited a normal karyotype and retained the ability to differentiate into cell types of the three germ layers. The iPSC lines will be useful for the study of the AD molecular and cellular mechanisms and drug screening.


Asunto(s)
Enfermedad de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Línea Celular , Células Madre Pluripotentes Inducidas , Diferenciación Celular , Fibroblastos , Marcadores Genéticos , Heterocigoto , Humanos , Cariotipo , Masculino , Persona de Mediana Edad , Piel
14.
Stem Cell Res ; 34: 101376, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30660867

RESUMEN

Spinal muscular atrophy (SMA) is a neuromuscular disease caused by deletion or mutation in SMN1 gene. SMA human induced pluripotent stem cells (iPSCs) represent a useful and valid model for the study of the disorder, as they provide in vitro the target cells. We generated iPSCs from a SMA type I patient and SMA type II patient by using non-integrating episomal plasmid vectors. The resulting iPSCs are episomal-free, express pluripotency markers, display a normal karyotype, retain the mutation (homozygous deletion of SMN1) and are able to differentiate into the three germ layers.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Células Madre Pluripotentes Inducidas/patología , Atrofia Muscular Espinal/patología , Adulto , Línea Celular , Niño , Humanos
15.
Ticks Tick Borne Dis ; 10(2): 377-385, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30509727

RESUMEN

The study objective was to get more information on C. burnetii prevalence in wild birds and ticks feeding on them, and the potentialities of the pathogen dissemination over Europe by both. MATERIALS: Blood, blood sera, feces of wild birds and ticks removed from those birds or from vegetation were studied at two sites in Russia: the Curonian Spit (site KK), and the vicinity of St. Petersburg (site SPb), and at two sites in Bulgaria: the Atanasovsko Lake (site AL), and the vicinity of Sofia (site SR). METHODS: C. burnetii DNA was detected in blood, feces, and ticks by PCR (polymerase chain reaction). All positive results were confirmed by Sanger's sequencing of 16SrRNA gene target fragments. The antibodies to C. burnetii in sera were detected by CFR (complement fixation reaction). RESULTS: Eleven of 55 bird species captured at KK site hosted Ixodes ricinus. C. burnetii DNA was detected in three I. ricinus nymphs removed from one bird (Erithacus rubecula), and in adult ticks flagged from vegetation: 0.7% I. persulcatus (site SPb), 0.9% I. ricinus (site KK), 1.0% D. reticulatus (AL site). C. burnetii DNA was also detected in 1.4% of bird blood samples at SPb site, and in 0.5% of those at AL site. Antibodies to C. burnetii were found in 8.1% of bird sera (site SPb). C. burnetii DNA was revealed in feces of birds: 0.6% at AL site, and 13.7% at SR site. CONCLUSIONS: Both molecular-genetic and immunological methods were applied to confirm the role of birds as a natural reservoir of C. burnetii. The places of wild bird stopover in Russia (Baltic region) and in Bulgaria (Atanasovsko Lake and Sofia region) proved to be natural foci of C. burnetii infection. Migratory birds are likely to act as efficient "vehicles" in dispersal of C. burnetii -infested ixodid ticks.


Asunto(s)
Animales Salvajes/microbiología , Enfermedades de las Aves/epidemiología , Aves/microbiología , Coxiella burnetii/aislamiento & purificación , Ixodes/microbiología , Fiebre Q/veterinaria , Migración Animal , Animales , Anticuerpos Antibacterianos/sangre , Países Bálticos/epidemiología , Enfermedades de las Aves/microbiología , Bulgaria/epidemiología , Coxiella burnetii/genética , ADN Bacteriano/aislamiento & purificación , Reservorios de Enfermedades/microbiología , Reservorios de Enfermedades/veterinaria , Europa (Continente)/epidemiología , Heces/microbiología , Secuenciación de Nucleótidos de Alto Rendimiento , Ninfa/microbiología , Reacción en Cadena de la Polimerasa , Prevalencia , Fiebre Q/epidemiología , ARN Ribosómico 16S/aislamiento & purificación , Federación de Rusia/epidemiología , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/microbiología
16.
J Phys Condens Matter ; 30(3): 035401, 2018 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-29256437

RESUMEN

The evolution of the crystal structure and electrical transport properties of distorted layered transition metal dichalcogenide ReSe2 was studied under high pressure up to ~90 GPa by Raman spectroscopy and electrical resistivity measurements accompanied by ab initio electronic band structure calculations. Raman spectroscopy studies indicate an isostructural phase transition due to layer sliding at ~7 GPa, to the distorted 1T-phase which remains stable up to the highest pressures employed in these experiments. From a direct band gap semiconductor at ambient pressure, ReSe2 undergoes pressure-induced metallization at pressures ~35 GPa, in agreement with the ab initio calculations. Resistivity measurements performed with different loading conditions reveal the possible emergence of superconductivity, which is most likely not an intrinsic property of ReSe2, but is rather conditioned by internal stresses upon compression.

17.
Opt Express ; 25(1): 223-231, 2017 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-28085815

RESUMEN

Visualisation of complex nonlinear equation solutions is a useful analysis tool for various scientific and engineering applications. We have re-examined the geometrical interpretation of the classical nonlinear four-wave mixing equations for the specific scheme of a phase sensitive one-pump fiber optical parametric amplification, which has recently attracted revived interest in the optical communications due to potential low noise properties of such amplifiers. Analysis of the phase portraits of the corresponding dynamical systems provide valuable additional insight into field dynamics and properties of the amplifiers. Simple geometric approach has been proposed to describe evolution of the waves, involved in phase-sensitive fiber optical parametric amplification (PS-FOPA) process, using a Hamiltonian structure of the governing equations. We have demonstrated how the proposed approach can be applied to the optimization problems arising in the design of the specific PS-FOPA scheme. The method considered here is rather general and can be used in various applications.

19.
J Phys Condens Matter ; 28(38): 385801, 2016 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-27439023

RESUMEN

Non-trivial electronic properties of silver telluride and other chalcogenides, such as the presence of a topological insulator state, electronic topological transitions, metallization, and the possible emergence of superconductivity under pressure have attracted attention in recent years. In this work, we studied the electronic properties of silver selenide (Ag2Se). We performed direct current electrical resistivity measurements, in situ Raman spectroscopy, and synchrotron x-ray diffraction accompanied by ab initio calculations to explore pressure-induced changes to the atomic and electronic structure of Ag2Se. The temperature dependence of the electrical resistivity was measured up to 30 GPa in the 4-300 K temperature interval. Resistivity data showed an unusual increase in the thermal energy gap of phase I, which is a semiconductor under ambient conditions. Recently, a similar effect was reported for the 3D topological insulator Bi2Se3. Raman spectroscopy studies revealed lattice instability in phase I indicated by the softening of observed vibrational modes with pressure. Our hybrid functional band structure calculations predicted that phase I of Ag2Se would be a narrow band gap semiconductor, in accordance with experimental results. At a pressure of ~7.5 GPa, Ag2Se underwent a structural transition to phase II with an orthorhombic Pnma structure. The temperature dependence of the resistivity of Ag2Se phase II demonstrated its metallic character. Ag2Se phase III, which is stable above 16.5 GPa, is also metallic according to the resistivity data. No indication of the superconducting transition is found above 4 K in the studied pressure range.

20.
Artículo en Inglés, Ruso | MEDLINE | ID: mdl-27029334

RESUMEN

The article describes a clinical case of successful chemotherapeutic and radiation treatment of a patient with breast cancer and metastases to the brain and meninges and with a pronounced neurological deficit. The patient underwent combined treatment (whole brain radiation with TBD of 30 Gy and local radiation of a metastasis with TBD of 15 Gy associated with capecitabine therapy) with continued administration of capecitabine until improvement. A partial metastasis reduction by 50% and complete regression of the neurological deficit were observed. Disease-free period was 1 year and 10 months, and the overall survival amounted to 2 years.


Asunto(s)
Neoplasias Encefálicas , Neoplasias de la Mama , Capecitabina/administración & dosificación , Quimioradioterapia , Neoplasias Meníngeas , Adulto , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/terapia , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Femenino , Humanos , Neoplasias Meníngeas/patología , Neoplasias Meníngeas/secundario , Neoplasias Meníngeas/terapia , Metástasis de la Neoplasia
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