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1.
Dalton Trans ; 52(47): 18010-18017, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37986576

RESUMO

Pyridinium cesium cobalt nitrate, (PyH)CsCo2(NO3)6, obtained from a nitric acid solution crystallizes in the orthorhombic space group Pnma with unit cell parameters a = 8.6905(14) Å, b = 11.9599(18) Å, c = 18.386(3) Å, V = 1911.0(5) Å3, and Z = 4. It consists of [Co(NO3)3]- layers, in which each Co2+ ion is connected with four monodentate bridging NO3-groups and one bidentate terminal NO3-group, forming a corrugated rectangular net. Magnetization and specific heat measurements show that (PyH)CsCo2(NO3)6 undergoes a long-range canted antiferromagnetic ordering in two steps at TC1 = 5.0 K and TC2 = 2.6 K. The temperature dependence of the magnetic susceptibility and the field dependence of the magnetization measured for (PyH)CsCo2(NO3)6 show that it is an Ising antiferromagnet. In support of these observations, our DFT + U + SOC calculations show that the Co2+ ions of (PyH)CsCo2(NO3)6 have an easy-axis magnetic anisotropy with preferred spin orientation along the b-axis. To a first approximation, the spin lattice of (PyH)CsCo2(NO3)6 is a weakly alternating Ising antiferromagnetic chain (J1/J2 ∼ 0.85), and these chains interact weakly (J3/J2 ∼ 0.07) to form a rectangular Ising antiferromagnetic lattice. In agreement with the prediction for a rectangular Ising antiferromagnet by Onsager, (PyH)CsCo2(NO3)6 undergoes a long-range antiferromagnetic ordering.

2.
Zh Vopr Neirokhir Im N N Burdenko ; 87(5): 110-116, 2023.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-37830476

RESUMO

After several years of waiting due to the "covid quarantine" and subsequent restrictions, we finally met. Epidemiological restrictions prevented the planned interim congress in 2021. The Third Congress on Functional and Stereotactic Neurosurgery was held in Moscow on March 15-17, 2023. Despite the widespread use of the online conference format, the Congress was attended by almost everyone who is in one way or another associated with functional and stereotactic neurosurgery in our country. International participation was also present despite the existing sanctions restrictions.


Assuntos
Neurocirurgia , Humanos , Procedimentos Neurocirúrgicos , Imageamento Tridimensional , Moscou
3.
Vestn Otorinolaringol ; 88(3): 86-89, 2023.
Artigo em Russo | MEDLINE | ID: mdl-37450397

RESUMO

Schwannoma is a benign neoplasm that develops from the Schwann cells of the nerve sheath. The share of neurogenic tumors of the parapharyngeal space accounts for 0.5% of all neoplasms of this localization. The article demonstrates a case from practice, presents the clinical features, diagnostics and methods of treatment for patients with pharyngeal neuromas. The peculiarity of the presented clinical observation is due to the rare occurrence of this pathology and the large size of the schwannoma in the long-term asymptomatic course of the disease.


Assuntos
Neurilemoma , Neoplasias Faríngeas , Humanos , Espaço Parafaríngeo/cirurgia , Espaço Parafaríngeo/patologia , Faringe , Neurilemoma/diagnóstico , Neurilemoma/cirurgia , Neurilemoma/patologia , Neoplasias Faríngeas/diagnóstico , Neoplasias Faríngeas/cirurgia
4.
Vestn Otorinolaringol ; 88(2): 86-88, 2023.
Artigo em Russo | MEDLINE | ID: mdl-37184560

RESUMO

Conservative therapy for chronic polyposis rhinosinusitis are well covered, and modern endoscopic rhinosurgery can effectively cope with this pathology. Clinical cases of large destructive anthrochoanal polyps are not uncommon, the pathology is well studied. However, cases with giant sinonasal polyposis, which lead to bone-destructive changes in the bones of the nose and the walls of the paranasal sinuses are very rare. We found only one case similar to the clinical observation presented in this article.


Assuntos
Pólipos Nasais , Neoplasias Nasofaríngeas , Seios Paranasais , Sinusite , Humanos , Cavidade Nasal , Pólipos Nasais/complicações , Pólipos Nasais/diagnóstico , Pólipos Nasais/cirurgia , Nariz/patologia , Neoplasias Nasofaríngeas/patologia , Doença Crônica
6.
Sovrem Tekhnologii Med ; 13(5): 24-29, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35265346

RESUMO

The aim of the study was to explore the use of 2D gait analysis for assessing gait abnormalities in patients with spastic tetraparesis associated with spinal cord injury and other lesions of the cervical spinal cord. Materials and Methods: The study included 12 patients with tetraparesis of various etiologies. Gait assessment was performed by video analysis using reflective markers (1.5 cm) and a special walking platform. The spatial coordinates of the markers were determined by capturing the reflected light with infrared LEDs located around the lenses of video cameras. Results: Using 2D gait analysis, numerical indicators of gait disturbance in spastic tetraparesis were obtained. We found a prolongation of the stand phase with a shortening of the swing phase (from 81.9 [76.1; 89.2] to 85.3 [74.4; 90.2]%; p=0.97) and the period of the double step (from 0.50 [0.45; 0.96] to 0.40 [0.34; 0.66]; p=0.4) in comparison with the target (normal) values (60% - for the stand phase; 1.41 - for the double-step period). The movements in the hip, knee, and ankle joints are described using numerical values.We then compared the data obtained from the left and right sides of the patient's body: there were no statistically significant differences between the two sets of data. We also compared the gait characteristics before and after treatment (in 4 patients). Statistically significant differences in values were obtained for the stand and swing phases (p=0.035), the range of motion in the hip joint (p=0.01), and gait velocity (p=0.046). Kendall's analysis revealed no significant correlation between the data obtained by video gait analysis and the gait changes by the Modified Ashworth Scale (р>0.05). Conclusion: 2D gait analysis is a promising method for quantifying gait disturbance in patients with spastic tetraparesis. It allows one to identify characteristic gait patterns, in particular, an increase in the stand phase with a shortening of the swing phase and the double step period, as well as a decrease in the range of motion in the hip joints with an increase in the knee and ankle ones.


Assuntos
Análise da Marcha , Espasticidade Muscular , Marcha , Humanos , Espasticidade Muscular/diagnóstico , Amplitude de Movimento Articular , Caminhada
7.
Vestn Otorinolaringol ; 85(1): 88-93, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32241997

RESUMO

INTRODUCTION: For the last decades endoscopic ear surgery has become a common practice. Advantages of the endoscopic technique in middle ear surgery are high definition and magnification of the endoscope with a modern camera and the ability to 'look around the corner' with the angled scope. MATERIAL AND METHODS: From March 2017 to November 2019 in NSRC PHOI named after Dmitry Rogachev in the Department of Oncology and Pediatric Surgery 53 patients (81 surgeries) have undergone endoscopic-assisted ear surgery: 3 biopsies for middle ear neoplasm with the transcanal endoscopic approach, 1 endoscopic tympanoplasty for attic retraction pocket with cholesteatoma, 2 endoscopic removal of middle ear tumors (including 1 combined approach) and 32 endoscopic myringoplasties, 22 canal wall down mastoidectomies for extensive middle ear and mastoid cholesteatoma, 21 second-look surgery with ossiculoplasty with overall good outcome. Age of the patients varied from 2 months to 16 years. Follow up period varied from 1 month to 3 years. RESULTS: Two cases of middle ear tumor removal via endoscopic transcanal approach are described. In one case endoscopic transmeatal approach was used as an addition to the middle fossa approach for removal of facial nerve neurinoma located on the upper surface of petrous bone with expansion to the middle ear cavity. In the second case endoscopic transmeatal approach was used alone for removal of benign tumor (salivary gland choristoma) of middle ear cavity with extension to pneumatic system of petrous bone. In both cases endoscopic approach allowed to biopsy the tumor first and then to remove the tumor in a less invasive way, which lead to faster patient recovery. CONCLUSION: In the majority of cases endoscopic technique is a method of assistance in otologic surgery, but sometimes could be a used a single method in middle ear surgery, allowing less traumatic approach and the implementation of high-definition camera for more precise disease control. In our preliminary experience endoscopic technique could be used in pediatric practice independently of the patient's age.


Assuntos
Colesteatoma da Orelha Média/cirurgia , Procedimentos Cirúrgicos Otológicos , Criança , Orelha Média , Endoscopia , Humanos , Processo Mastoide , Estudos Retrospectivos , Resultado do Tratamento
8.
Sovrem Tekhnologii Med ; 12(1): 79-83, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34513041

RESUMO

Patients with severe muscular spasticity still represent the most complex and resistant to therapy group of neuro-rehabilitation patients. In a few years, in Russia, intrathecal baclofen therapy has appeared to be the most effective method for such spasticity. For the first time the authors developed and implemented in clinical practice "Prospective register to treat spastic states using intrathecal baclofen therapy in Russian Federation" aimed at therapy classification of spastic patients: to reveal management characteristics, assess treatment outcomes and frequency of occurrence of adverse events that will finally help specify the need for the method employment in real clinical practice. The article presents the findings of a one-year usage of Register, which enabled to make a preliminary evaluation of intrathecal baclofen therapy in Russia.

9.
Biochemistry (Mosc) ; 84(10): 1204-1212, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31694516

RESUMO

Cholestasis of pregnancy is a pathology associated with disruptions in the bile flow and dysregulation of salt and water homeostasis. Prolactin is one of the most important regulators of salt and water balance. Changes in the expression of long and short isoforms of the prolactin receptor (PrlR) and mediators of prolactin signaling were studied by immunoblotting and RT-qPCR in the rat kidney cortex and outer medulla in the model of cholestasis of pregnancy. Both PrlR isoforms were shown to participate in the effects of prolactin in cholestasis of pregnancy. Direct impact of prolactin on the kidney has been demonstrated: (i) mRNA expression of both PrlR isoforms in the kidney depended on the physiological conditions and prolactin levels; (ii) expression of pSTAT5, a key mediator of the long PrlR isoform signaling, was increased in animals with cholestasis of pregnancy; (iii) in the case of long PrlR isoform predomination, expression of mRNAs for the prolactin signaling inhibitors SOCS3 and PIAS3 was upregulated (the genes of these regulators contain STAT-responsive elements in their promoters); (iv) expression of the mRNA for galactose-1-phosphate uridyltransferase (GALT), a molecular target of the PrlR short isoform, was decreased in the kidney outer medulla.


Assuntos
Colestase/metabolismo , Modelos Animais de Doenças , Rim/metabolismo , Prolactina/metabolismo , Transdução de Sinais , Animais , Feminino , Gravidez , Isoformas de Proteínas/metabolismo , Ratos , Receptores da Prolactina/metabolismo
10.
Acta Naturae ; 11(2): 42-46, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413878

RESUMO

Homozygous siblings with different treatment histories represent an excellent model to study both the phenotypic manifestation of mutations and the efficacy of therapy. We compared phenylketonuria (PKU) manifestations in two different gender siblings who were homozygous carriers of a rare phenylalanine hydroxylase (PAH) mutation, p.R155H, subjected to different treatments. PKU caused by mild mutations may be easily underdiagnosed if the diagnosis is based solely on the phenylalanine (Phe) blood concentration. One of the described patients is an example of this diagnostic error. For reducing diagnostic errors, we suggest the use of more elaborate methods in screening practice, in particular mass spectrometric analysis of blood metabolites, the efficiency of which is demonstrated in the present study.

11.
Sci Data ; 6: 190007, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30720800

RESUMO

In this work, we compare the resolution of V2-V3 and V3-V4 16S rRNA regions for the purposes of estimating microbial community diversity using paired-end Illumina MiSeq reads, and show that the fragment, including V2 and V3 regions, has higher resolution for lower-rank taxa (genera and species). It allows for a more precise distance-based clustering of reads into species-level OTUs. Statistically convergent estimates of the diversity of major species (defined as those that together are covered by 95% of reads) can be achieved at the sample sizes of 10000 to 15000 reads. The relative error of the Shannon index estimate for this condition is lower than 4%.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Metagenômica/métodos , Microbiota/genética , RNA Ribossômico 16S/genética , Microbiologia da Água , Bactérias/genética , Biologia Computacional/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Lagos , Federação Russa , Análise de Sequência de DNA
12.
Steroids ; 145: 5-18, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30753845

RESUMO

Progesterone (P4) and its analogues regulate various reproductive processes, such as ovulation, implantation, pregnancy maintenance and delivery. In these processes, an important role is played by the immune cells recruited to the female reproductive organs and tissues, where they are exposed to the action of P4. Progestins regulate cellular processes, acting through nuclear steroid receptors (nSRs), membrane P4 receptors (mPRs), and through the sensors. It remains unclear, what type of receptors is used by P4 and its derivatives to exert their effect on the immune cells and how similar their effects are in different types of these cells. We have previously synthesized new progesterone derivatives, among which two selective mPRs ligands, not interacting with nSRs were identified. The objective of this study was to examine the effects of P4 and new selective mPRs ligands on the expression of pro- and anti-inflammatory cytokines in activated human peripheral blood mononuclear cells (PBMCs), THP-1 monocyte cells, and Jurkat T cells. It was demonstrated that the action of P4 and selective ligands was unidirectional, but in different types of the immune cells, their effects were different, and sometimes even opposite. In PBMCs, exposure to these steroids resulted in the increase of mRNA and secreted protein levels of IL-1ß, TNFα, and IL-6 cytokines, as well as in the increase of INFγ mRNA level, decrease of IL-2 mRNA level, increase of TGFß mRNA level, and decrease of IL-4 mRNA and IL-10 secreted protein levels. In monocytes, similarly to PBMCs, expression of IL-1ß and TNFα mRNA was increased, but expression of IL-10 was also increased, and the TGFß expression statistically significantly remained the same. In Jurkat T cells, expression of IL-2 and TNFα mRNA decreased, while expression of IL-10 increased, and expression of TGFß did not change. Thus, progestins act on the immune cells through mPRs and have both pro- and anti-inflammatory effects, depending on the phenotypes of these cells. The data obtained are important for understanding the complexity of the immune system regulation by progestins, which depends on the type of the immune cells and individual characteristics of the immune system.


Assuntos
Membrana Celular/metabolismo , Fatores Imunológicos/farmacologia , Progesterona/farmacologia , Receptores de Progesterona/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-10/genética , Interleucina-10/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Células Jurkat , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Ligantes , Masculino , RNA Mensageiro/genética , Caracteres Sexuais , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
13.
Biochemistry (Mosc) ; 83(5): 574-585, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29738691

RESUMO

Identification of progesterone selective agonists and antagonists that act through one of the nuclear progesterone receptor isoforms is of particular importance for the development of tissue-specific drugs in gynecology and anticancer therapy. Fourteen pregna-D'6- and pregna-D'3-pentarane progesterone derivatives with 16α,17α-cycloalkane groups and two progesterone 3-deoxyderivatives were examined for their ability to regulate transcriptional activity of human nuclear progesterone receptor isoform B (nPR-B) expressed in Saccharomyces cerevisiae yeast. Transcriptional activity of nPR-B was measured from the expression of the ß-galactosidase reporter gene with a hormone-responsible element in the promoter. Among the compounds tested, two were full progesterone agonists, four were partial agonists, one compound possessed both agonistic and antagonistic activity, one compound displayed only partial antagonistic activity, and eight compounds did not show any activity. Modifications of the pentarane structure, precisely, introduction of an additional double bound in the A or B rings and/or modification at the 6th position of progesterone, lead to a switch from the complete agonistic activity to partial agonistic or mixed activities. These modifications enable progestins to act as selective modulators of progesterone receptor. Steroids with reduced A-ring and 3-ketogroups lose their ability to regulate PR-B activity. Both 3-deoxycompounds, being selective ligands of progesterone membrane receptors, do not affect PR-B activity.


Assuntos
Núcleo Celular/efeitos dos fármacos , Progesterona/farmacologia , Receptores de Progesterona/agonistas , Receptores de Progesterona/antagonistas & inibidores , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Transcrição Gênica/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Núcleo Celular/metabolismo , Modelos Biológicos , Progesterona/análogos & derivados , Progesterona/química , Receptores de Progesterona/genética , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/metabolismo , Transcrição Gênica/genética , Ativação Transcricional/genética
14.
Sci Rep ; 7(1): 4589, 2017 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-28676703

RESUMO

A quantum critical point (QCP) is currently being conjectured for the BaFe2(As1-x P x )2 system at the critical value x c ≈ 0.3. In the proximity of a QCP, all thermodynamic and transport properties are expected to scale with a single characteristic energy, given by the quantum fluctuations. Such a universal behavior has not, however, been found in the superconducting upper critical field H c2. Here we report H c2 data for epitaxial thin films extracted from the electrical resistance measured in very high magnetic fields up to 67 Tesla. Using a multi-band analysis we find that H c2 is sensitive to the QCP, implying a significant charge carrier effective mass enhancement at the doping-induced QCP that is essentially band-dependent. Our results point to two qualitatively different groups of electrons in BaFe2(As1-x P x )2. The first one (possibly associated to hot spots or whole Fermi sheets) has a strong mass enhancement at the QCP, and the second one is insensitive to the QCP. The observed duality could also be present in many other quantum critical systems.

15.
Dalton Trans ; 46(13): 4430-4434, 2017 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-28304020

RESUMO

Ionic liquids that are stable toward oxidation and nitration and are based on the 1-n-butyl-3-methylimidazolium cation (BMIm+) can be used as solvents and reaction media for copper dissolution in liquid dinitrogen tetraoxide N2O4. The ionic liquid not only favors the dissociation of N2O4 into NO+ and NO3-, but also takes part in the formation of different crystalline products. Thus, NO[BF4], NO[Cu(NO3)3] and (BMIm)2[Cu2(CF3COO)6] were prepared using (BMIm)A, A- = [BF4]-, (CF3SO2)2N-, CF3COO-, respectively. The formation of a certain product is determined by the nature of the anion A- and the relative solubility of the reaction products in the ionic liquid. Crystals of NO[BF4] were also prepared directly from a mixture of N2O4 and BMImBF4. According to XRD single-crystal structure analysis, the structure of NO[BF4] consists of tetrahedral [BF4]- anions and nitrosonium NO+ cations; the formation of these ions prove the heterolytic dissociation of N2O4 dissolved in the ionic liquid. The crystal structure of the earlier unknown binuclear copper trifluoroacetate (BMIm)2[Cu2(CF3COO)6] were determined by X-ray diffraction. The peculiarity of this dimer compared to the majority of known dimeric copper(ii) carboxylates is the unusually long CuCu distance (3.15 Å), with Cu(ii) ions demonstrating an atypical coordination of a distorted trigonal bipyramid formed by five O atoms of five trifluoroacetate groups.

16.
Parazitologiia ; 51(1): 38-44, 2017.
Artigo em Russo | MEDLINE | ID: mdl-29401574

RESUMO

The taiga tick (Icodes persulcatus, Schulze, 1930) is the main and most epidemiologically dangerous vector of tick-born encephalitis virus (TBEV) and Borrelia in most parts of Russia's territory (Alekseev et al., 2008). The purpose of this article is to describe the incidence rate of I. persulcatus males with exoskeleton anomalies in populations of the Asiatic part of Russia. A total of 2630 taiga tick males were morphologically analyzed. They were collected in Far Eastern, Siberian and Ural Federal Districts (respectively, FEFD, SFD, UFD) in 15 geographically remote locations. It is shown that in all populations there are adult ticks with impaired exoskeleton, among which two types dominate: twin dents at the back of conscutum (P11), and uneven surface of conscutum - a "shagreen skin" (P9). The frequency of abnormalities in males from the areas with temperate monsoon and temperate continental climate (FEFD) was definitely lower (6.5 ± 1.05 %), than in individuals from the territories of SFD (29.7 ± 1.03 %) and UFD (25.8 ± 3.93 %) with continental and sharply continental climate. FEFD territory is also characterized by a less number of males having two simultaneous exoskeleton anomalies. Similar district-preconditioned differences in the frequency of recorded body distortions are also typical of females, with a higher percentage of deviant individuals in comparison with males. Thus, the identified polymorphism of exoskeleton structure of the taiga tick may reflect the natural phenogeographical variability of this trait and might not be the result of human impact.


Assuntos
Exoesqueleto/anormalidades , Ixodes/anatomia & histologia , Animais , Clima , Feminino , Ixodes/genética , Masculino , Fenótipo , Sibéria
17.
Nanoscale ; 8(41): 17809-17814, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27714058

RESUMO

The advantage of metasurfaces and nanostructures with a high nonlinear response is that they do not require phase matching, and the generated pulses are short in the time domain without additional pulse compression. However, the fabrication of large-scale planar structures by lithography-based methods is expensive, time consuming, and requires complicated preliminary simulations to obtain the most optimized geometry. Here, we propose a novel strategy for the self-assembled fabrication of large-scale resonant metasurfaces, where incident femtosecond laser pulses adjust the initial silicon films via specific surface deformation to be as resonant as possible for a given wavelength. The self-adjusting approach eliminates the necessity of multistep lithography and designing, because interference between the incident and the scattered parts of each laser pulse "imprints" resonant field distribution within the film. The self-adjusted metasurfaces demonstrate a high damage threshold (≈1012 W cm-2) and efficient frequency conversion from near-IR to deep UV. The conversion efficiency is up to 30-fold higher compared with nonresonant smooth Si films. The resulting metasurfaces allow for the generation of UV femtosecond laser pulses at a wavelength of 270 nm with a high peak and average power (≈105 W and ≈1.5 µW, respectively). The results pave the way to the creation of ultrathin nonlinear metadevices working at high laser intensities for efficient deep UV generation at the nanoscale.

18.
Eksp Klin Farmakol ; 79(2): 9-13, 2016.
Artigo em Russo | MEDLINE | ID: mdl-27416676

RESUMO

In a placebo-controlled study, changes in psychophysiological status of operators (38 healthy male volunteers aged 23-35 years) performing 4-hour model operator activity were evaluated after a single oral administration of typical representatives of the different classes of drugs (haloperidol, proroxan, yohimbine hydrochloride, propranolol, mesocarb, isoprenaline, Belladonna extract, anabasine hydrochloride, valproate sodium, and phenazepam), which are used for the treatment, rehabilitation and prophylaxis of common diseases. It was found that all the drugs modified to a greater or lesser extent some components of the model operator activity. Isoprenaline and phenazepam had the most negative effect on the psychophysiological indicators and quality of the modeled operator activity. The results should be considered before administration of such drugs to working operators.


Assuntos
Atenção/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/farmacologia , Análise e Desempenho de Tarefas , Tranquilizantes/farmacologia , Adulto , Anabasina/farmacologia , Atenção/fisiologia , Alcaloides de Belladona/farmacologia , Benzodiazepinas/farmacologia , Dioxanos/farmacologia , Método Duplo-Cego , Haloperidol/farmacologia , Humanos , Isoproterenol/farmacologia , Masculino , Propranolol/farmacologia , Psicofisiologia , Sidnonas/farmacologia , Ácido Valproico/farmacologia , Ioimbina/farmacologia
19.
Mol Biol (Mosk) ; 50(1): 10-26, 2016.
Artigo em Russo | MEDLINE | ID: mdl-27028807

RESUMO

Progesterone and its analogs may exert opposite effects on cell proliferation, apoptosis, and epithelial-mesenchymal transition, leading to higher cell motility and metastasis. Their ultimate effect is determined by a number of factors: the structure and concentration of the steroid, its affinity for various forms of steroid hormone receptors, activation of nongenomic mechanisms, the composition and proportion of different progesterone receptors and sensors, activity of various signaling pathways, the set of transcription factor coregulators, DNA accessibility in chromatin, activity of steroid-metabolizing enzymes, intercellular interactions within tissues, the hormonal status of the body, disease stage, and species-specific features. The review considers the factors that determine the role progestins play in proliferation and apoptosis of human tumor cells of various origins.


Assuntos
Carcinogênese , Neoplasias/metabolismo , Neoplasias/patologia , Progestinas/metabolismo , Apoptose , Proliferação de Células , Humanos , Receptores de Progesterona/metabolismo , Transdução de Sinais
20.
Sci Rep ; 6: 18620, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26729630

RESUMO

Iron-based superconductors have been found to exhibit an intimate interplay of orbital, spin, and lattice degrees of freedom, dramatically affecting their low-energy electronic properties, including superconductivity. Albeit the precise pairing mechanism remains unidentified, several candidate interactions have been suggested to mediate the superconducting pairing, both in the orbital and in the spin channel. Here, we employ optical spectroscopy (OS), angle-resolved photoemission spectroscopy (ARPES), ab initio band-structure, and Eliashberg calculations to show that nearly optimally doped NaFe0.978Co0.022As exhibits some of the strongest orbitally selective electronic correlations in the family of iron pnictides. Unexpectedly, we find that the mass enhancement of itinerant charge carriers in the strongly correlated band is dramatically reduced near the Γ point and attribute this effect to orbital mixing induced by pronounced spin-orbit coupling. Embracing the true band structure allows us to describe all low-energy electronic properties obtained in our experiments with remarkable consistency and demonstrate that superconductivity in this material is rather weak and mediated by spin fluctuations.

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