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1.
Nature ; 607(7918): 260-265, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35831598

RESUMO

In spite of the high-density and strongly correlated nature of the atomic nucleus, experimental and theoretical evidence suggests that around particular 'magic' numbers of nucleons, nuclear properties are governed by a single unpaired nucleon1,2. A microscopic understanding of the extent of this behaviour and its evolution in neutron-rich nuclei remains an open question in nuclear physics3-5. The indium isotopes are considered a textbook example of this phenomenon6, in which the constancy of their electromagnetic properties indicated that a single unpaired proton hole can provide the identity of a complex many-nucleon system6,7. Here we present precision laser spectroscopy measurements performed to investigate the validity of this simple single-particle picture. Observation of an abrupt change in the dipole moment at N = 82 indicates that, whereas the single-particle picture indeed dominates at neutron magic number N = 82 (refs. 2,8), it does not for previously studied isotopes. To investigate the microscopic origin of these observations, our work provides a combined effort with developments in two complementary nuclear many-body methods: ab initio valence-space in-medium similarity renormalization group and density functional theory (DFT). We find that the inclusion of time-symmetry-breaking mean fields is essential for a correct description of nuclear magnetic properties, which were previously poorly constrained. These experimental and theoretical findings are key to understanding how seemingly simple single-particle phenomena naturally emerge from complex interactions among protons and neutrons.

2.
Dokl Biochem Biophys ; 515(1): 36-40, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38189890

RESUMO

The search for new cytotoxic agents capable of lysing tumor cells is an important task in the fight against cancer. Here we have shown that the HspBP1 protein, the chaperone of the heat shock protein Hsp70, is able to form a complex with the previously discovered peptide (17.1) of the innate immunity protein Tag7. Experiments using thermophoresis demonstrated that the affinity of the Tag7 protein peptide 17.1 to the HspBP1 molecule is 100 times higher than that of the full-sized Tag7 molecule. The addition of the 17.1-HspBP1 complex to tumor cells induces apoptosis and necroptosis in them. The results obtained in this work can be used to develop promising antitumor drugs.


Assuntos
Receptores Tipo I de Fatores de Necrose Tumoral , Apoptose , Proteínas de Choque Térmico HSP70/metabolismo , Imunidade Inata , Peptídeos/farmacologia
3.
Dokl Biochem Biophys ; 509(1): 78-80, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37340298

RESUMO

On the basis of known published data, six peptide sequences were selected that are potentially capable of being rapidly cleaved by the endosomal protease cathepsin B. For comparison, the cleavage of common linker sequences, polyglycine and polyglycine-serine, by cathepsin B was also studied. Different ends of these peptides were labeled with sulfoCyanine3 and sulfoCyanine5 fluorescent dyes, between which Förster resonant energy transfer (FRET) is possible. The kinetics of cleavage of peptides by cathepsin B was studied on a multimodal plate reader by FRET signal reduction. FKFL and FRRG cleavage sites have been shown to be the most suitable for potential use in various drug delivery systems. These sites are much more efficiently cleaved under slightly acidic conditions of endosomes than at neutral extracellular pH.


Assuntos
Aminoácidos , Catepsina B , Catepsina B/química , Catepsina B/metabolismo , Aminoácidos/metabolismo , Cinética , Peptídeos/química , Endossomos/metabolismo , Sistemas de Liberação de Medicamentos
4.
Morphologie ; 107(356): 138-141, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35241388

RESUMO

Variations at the skull base can result in misinterpretation of radiological imaging and occasionally, iatrogenic injury. Here, we describe, to our knowledge, the second reported case of a duplicated foramen rotundum. The morphometrics of this finding are documented and the anatomy and potential clinical consequences of such an anatomical variation discussed. Such a finding is of archival value. Additionally, foramen rotundum duplication such as found in our case might also lead to complications while using, for example, transsphenoid approaches to the middle cranial fossa as well as various transfacial treatments for trigeminal neuralgia which rely on observing the foramina around the foramen ovale on fluoroscopy for correct positioning of needles and catheters.


Assuntos
Osso Esfenoide , Neuralgia do Trigêmeo , Humanos , Base do Crânio , Neuralgia do Trigêmeo/diagnóstico por imagem , Neuralgia do Trigêmeo/etiologia , Variação Anatômica
5.
Dokl Biochem Biophys ; 510(1): 87-90, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37582868

RESUMO

On the basis of literature data, an antibody-like molecule, monobody, was selected that is capable of interacting with the nucleocapsid protein (N protein) of the SARS-CoV-2 virus with a high affinity (dissociation constant 6.7 nM). We have previously developed modular nanotransporters (MNTs) to deliver various molecules to a selected compartment of target cells. In this work, a monobody to the N protein of the SARS-CoV-2 virus was inserted in the MNT using genetic engineering methods. In this MNT, a site for the cleavage of the monobody from the MNT in endosomes was also inserted. It was shown by thermophoresis that the cleavage of this monobody from the MNT by the endosomal protease cathepsin B leads to a 12-fold increase in the affinity of the monobody for the N protein. Cellular thermal shift assay showed the ability of the obtained MNT to interact with the N protein in A431 cells transfected with the SARS-CoV-2 N protein fused to the mRuby3 fluorescent protein.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Proteínas do Nucleocapsídeo
6.
Dokl Biochem Biophys ; 513(Suppl 1): S63-S66, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38379079

RESUMO

Two eukaryotic cell lines, A549 and A431, with stable expression of the nucleocapsid protein (N-protein) of the SARS-CoV-2 virus fused with the red fluorescent protein mRuby3 were obtained. Using microscopy, the volumes of the cytoplasm and nucleus were determined for these cells. Using quantitative immunoblotting techniques, the concentrations of the N-mRuby3 fusion protein in their cytoplasm were assessed. They were 19 and 9 µM for A549 and A431 cells, respectively. Using these concentrations, the initial rate of N-protein degradation in the studied cells was estimated from the decrease in cell fluorescence. In A549 and A431 cells, it was the same (84 nM per hour). The approach of quantitatively describing the degradation process can be applied to analyze the effectiveness of a wide class of antiviral drugs that cause degradation of viral proteins.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/metabolismo , Proteínas do Nucleocapsídeo/metabolismo , Citoplasma/metabolismo , Proteólise
7.
Dokl Biochem Biophys ; 513(Suppl 1): S60-S62, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38379080

RESUMO

Modular nanotransporters (MNTs) containing an antibody-like molecule, monobody, to the N­protein of the SARS-CoV-2 virus, as well as an amino acid sequence that recruits the Keap1 E3 ligase (E3BP) were created. This MNT also included a site for cleavage of the E3BP monobody from the MNT in acidic endocytic compartments. It was shown that this cleavage by the endosomal protease cathepsin B leads to a 2.7-fold increase in the affinity of the E3BP monobody for the N-protein. Using A549 cells with transient expression of the N-protein fused with the fluorescent protein mRuby3, it was shown that incubation with MNT leads to a significant decrease in mRuby3 fluorescence. It is assumed that the developed MNTs can serve as a basis for the creation of new antiviral drugs against the SARS-CoV-2 virus.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Células A549 , Proteína 1 Associada a ECH Semelhante a Kelch , Fator 2 Relacionado a NF-E2
8.
Dokl Biochem Biophys ; 509(1): 70-72, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37340296

RESUMO

A modular nanotransporter (MNT) carrying the sequence of an antibody-like molecule, anti-c-Myc nanobody, was synthesized and characterized. It was demonstrated that the created MNT is able to interact with the target protein, c-Myc oncogene, with a dissociation constant of 46 ± 14 nM, internalize into target cells, change Myc-dependent expression, and exert an antiproliferative effect.

9.
Morphologie ; 106(352): 66-69, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33610465

RESUMO

Detailed knowledge of the anatomy and different variations of the saphenous nerve could be of great importance not only to anatomists but also to clinicians. There are very few studies of saphenous nerve morphology in thigh. Most of the reported variations of this nerve concern the infrapatellar branch. In contrast, a saphenous plexus has been described in only one case. Herein, we present an unusual case of unilateral saphenous plexus formation in the right thigh found during routine anatomical dissection of a 69-year-old male Caucasian cadaver. We also present a brief discussion of the saphenous plexus and emphasize its potential clinical implications.


Assuntos
Dissecação , Coxa da Perna , Idoso , Cadáver , Humanos , Masculino
10.
Dokl Biochem Biophys ; 503(1): 90-92, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35538285

RESUMO

Seven amino acid sequences of antibody mimetics molecules, monobodies, capable of interacting with the nucleocapsid protein of the SARS-CoV virus, were taken from the literature. Nucleotide sequences of monobody genes were obtained by gene synthesis, which were expressed in E. coli and isolated using Ni-NTA chromatography. It was shown by thermophoresis that three of the seven selected antibody-like molecules can interact with high affinity (dissociation constant of tens of nM) with the nucleocapsid protein of the SARS-CoV-2 virus. For the remaining four monobodies, only low affinity binding with a dissociation constant of several µM was found.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Escherichia coli/genética , Humanos , Proteínas do Nucleocapsídeo/genética
11.
Dokl Biochem Biophys ; 506(1): 220-222, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36303056

RESUMO

Based on previous studies, two antibody-like molecules, monobodies, capable of high-affinity interaction with the SARS-CoV-2 nucleocapsid protein (dissociation constant of tens of nM) were selected. For delivery to target cells, genetically engineered constructs containing monobody and TAT peptide, placed either at the N- or C-terminus of the resulting polypeptide, were produced and expressed in E. coli. The construct with the highest affinity to the SARS-CoV-2 nucleocapsid protein was revealed with the use of thermophoresis technique. Cellular thermal shift assay demonstrated the ability of this construct to interact with the nucleocapsid protein within HEK293T cells transfected with the SARS-CoV-2 nucleocapsid protein fused to the mRuby3 fluorescent protein. Replacement of TAT peptide to S10 shuttle peptide, containing endosomolytic peptide, significantly improved the penetration of the construct into the target cells.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Escherichia coli/genética , Escherichia coli/metabolismo , Células HEK293 , Proteínas do Nucleocapsídeo/química , Proteínas do Nucleocapsídeo/metabolismo , Anticorpos Antivirais
12.
Dokl Biochem Biophys ; 506(1): 181-184, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36303048

RESUMO

One of the basic features of immune system is the ability to sustain balance between activation and suppression of effector lymphocytes. In this process a key role belongs to the subpopulation of cells called regulatory T cells (Treg). Many cancer and autoimmune diseases are caused by malfunctions of Treg, and investigation of this subpopulation is important for development of new therapeutic approaches. In this study, we demonstrate that regulatory T cells can migrate along the concentration gradient of Tag7-Mts1 complex, and also they produce agents that induce blood cells migration.


Assuntos
Neoplasias , Linfócitos T Reguladores , Humanos , Quimiotaxia , Citocinas , Linfócitos
13.
Morphologie ; 105(350): 247-251, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34511180

RESUMO

The plantaris muscle (PM) typically begins with a short, fusiform muscle belly and continues as a slim tendon traversing distally between the gastrocnemius and soleus to attach into the calcaneus directly or Achilles tendon. Conventionally, it has been of most interest as a donor for surgeons plantaris tendon (PT) grafting and recent studies have implicated the PT in the development of Achilles tendinopathy. During routine cadaveric dissection, one such anatomical variation was identified in a cadaver with two distal tendons of the PM and also multiple tendon connections into the crural fascia. While similar variants have been reported before in isolation, to our knowledge, this has been rarely reported illustrating the coexistence of a duplicated PT with simultaneous fascial connections into the crural fascia. The clinical implications of such a finding are discussed.


Assuntos
Tendão do Calcâneo , Tendinopatia , Variação Anatômica , Fáscia , Humanos , Músculo Esquelético
14.
Phys Rev Lett ; 124(11): 112501, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32242689

RESUMO

The gyromagnetic factor of the low-lying E=251.96(9) keV isomeric state of the nucleus ^{99}Zr was measured using the time-dependent perturbed angular distribution technique. This level is assigned a spin and parity of J^{π}=7/2^{+}, with a half-life of T_{1/2}=336(5) ns. The isomer was produced and spin aligned via the abrasion-fission of a ^{238}U primary beam at RIKEN RIBF. A magnetic moment |µ|=2.31(14)µ_{N} was deduced showing that this isomer is not single particle in nature. A comparison of the experimental values with interacting boson-fermion model IBFM-1 results shows that this state is strongly mixed with a main νd_{5/2} composition. Furthermore, it was found that monopole single-particle evolution changes significantly with the appearance of collective modes, likely due to type-II shell evolution.

15.
Dokl Biochem Biophys ; 490(1): 47-49, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32342313

RESUMO

It was found that the use of a new strain-producer Escherichia coli, expressing the heme receptor ChuA, enables obtaining a hemin-containing modular nanotransporter (MNT) for drug delivery into the nuclei of target cells. The hemin-containing MNT becomes stabilized, which leads to an increase in its thermal stability and prevents aggregation of this protein.


Assuntos
Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Hemina/química , Receptores de Superfície Celular/química , Receptores de Superfície Celular/metabolismo , Antineoplásicos/farmacologia , Cromatografia em Gel , Portadores de Fármacos , Elétrons , Heme/química , Ligantes , Lisossomos/química , Nanotecnologia , Plasmídeos/metabolismo , Ligação Proteica , Temperatura
16.
Dokl Biochem Biophys ; 490(1): 22-24, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32342307

RESUMO

New recombinant carriers-modular nanotransporters (MNTs)-with N-terminal ligand module to the epidermal growth factor receptor (EGFR) were developed and characterized. Human epidermal growth factor (hEGF) and antibody-like protein Z1907 were used as a ligand module. We demonstrated that MNTs are able to internalize in a receptor-specific manner into the target cancer cells and to accumulate in the target cell nuclei. Conjugation of MNTs with the Auger electron emitter 111In significantly enhanced the cytotoxic effect of 111In on the target cells. It was found that the transfer of EGF from the C-terminus to the N-terminus of the MNT enhanced the proliferation of target cells, whereas the use of Z1907 did not have a similar effect.


Assuntos
Fator de Crescimento Epidérmico/química , Receptores ErbB/metabolismo , Proteínas Recombinantes/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Sistemas de Liberação de Medicamentos , Humanos , Radioisótopos de Índio/química , Ligantes , Células MCF-7 , Ligação Proteica , Domínios Proteicos
17.
Phys Rev Lett ; 122(19): 192502, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31144969

RESUMO

The change in mean-square nuclear charge radii δ⟨r^{2}⟩ along the even-A tin isotopic chain ^{108-134}Sn has been investigated by means of collinear laser spectroscopy at ISOLDE/CERN using the atomic transitions 5p^{2} ^{1}S_{0}→5p6 s^{1}P_{1} and 5p^{2} ^{3}P_{0}→5p6s ^{3}P_{1}. With the determination of the charge radius of ^{134}Sn and corrected values for some of the neutron-rich isotopes, the evolution of the charge radii across the N=82 shell closure is established. A clear kink at the doubly magic ^{132}Sn is revealed, similar to what has been observed at N=82 in other isotopic chains with larger proton numbers, and at the N=126 shell closure in doubly magic ^{208}Pb. While most standard nuclear density functional calculations struggle with a consistent explanation of these discontinuities, we demonstrate that a recently developed Fayans energy density functional provides a coherent description of the kinks at both doubly magic nuclei, ^{132}Sn and ^{208}Pb, without sacrificing the overall performance. A multiple correlation analysis leads to the conclusion that both kinks are related to pairing and surface effects.

18.
Dokl Biochem Biophys ; 484(1): 66-68, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31012017

RESUMO

The PBAF(SWI/SNF) multiprotein complex, which changes the chromatin structure, is widely involved in the regulation of eukaryotic gene expression. A specific component of this complex is the PHF10 protein, which is involved in recruiting this complex to chromatin. We showed that the PHF10 expression in cells of different lines is activated by the c-MYC oncogene. Since PHF10 stimulates cell proliferation, its c-MYC-dependent activation in cancer cells should lead to an increase in their proliferation rate.


Assuntos
Proteínas Cromossômicas não Histona/biossíntese , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/biossíntese , Proteínas de Neoplasias/biossíntese , Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição/biossíntese , Linhagem Celular Tumoral , Proteínas Cromossômicas não Histona/genética , Proteínas de Homeodomínio/genética , Humanos , Proteínas de Neoplasias/genética , Neoplasias/genética , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-myc/genética , Fatores de Transcrição/genética
19.
Phys Rev Lett ; 121(10): 102501, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30240248

RESUMO

Differences in mean-square nuclear charge radii of ^{100-130}Cd are extracted from high-resolution collinear laser spectroscopy of the 5s ^{2}S_{1/2}→5p ^{2}P_{3/2} transition of the ion and from the 5s5p ^{3}P_{2}→5s6s ^{3}S_{1} transition in atomic Cd. The radii show a smooth parabolic behavior on top of a linear trend and a regular odd-even staggering across the almost complete sdgh shell. They serve as a first test for a recently established new Fayans functional and show a remarkably good agreement in the trend as well as in the total nuclear charge radius.

20.
Phys Rev Lett ; 120(2): 022502, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29376727

RESUMO

The g factor of the 56 ns half-life isomeric state in ^{128}Cs has been measured using the time-differential perturbed angular distribution method. This state is the bandhead of the positive-parity chiral rotational band, which emerges when an unpaired proton, an unpaired neutron hole, and an even-even core are coupled such that their angular momentum vectors are aplanar (chiral configuration). g-factor measurements can give important information on the relative orientation of the three angular momentum vectors. The measured g factor g=+0.59(1) shows that there is an important contribution of the core rotation in the total angular momentum of the isomeric state. Moreover, a quantitative theoretical analysis supports the conclusion that the three angular momentum vectors lie almost in one plane, which suggests that the chiral configuration in ^{128}Cs demonstrated in previous works by characteristic patterns of electromagnetic transitions appears only above some value of the total nuclear spin.

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