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1.
Bull Exp Biol Med ; 176(6): 709-715, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38888647

RESUMO

The review presents the results of the blood substitute development based on perfluororganic compounds (PFC). The limitations of PFC due to which their further development was suspended are described. The presented data allows us to imagine a possible way to create optimal drugs based on PFC. Chemically inactive perfluorocomponents should be used - perfluorinated hydrocarbons and tertiary perfluorinated amines. However, in order to emulsify and stabilize the emulsion, other types of effective and chemically indifferent surfactants that do not interact with oxygen and other components of the drug are needed.


Assuntos
Substitutos Sanguíneos , Fluorocarbonos , Fluorocarbonos/química , Humanos , Tensoativos/química , Tensoativos/farmacologia , Emulsões/química , Oxigênio/química , Animais
2.
Phys Rev Lett ; 130(5): 051803, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36800477

RESUMO

The COHERENT Collaboration searched for scalar dark matter particles produced at the Spallation Neutron Source with masses between 1 and 220 MeV/c^{2} using a CsI[Na] scintillation detector sensitive to nuclear recoils above 9 keV_{nr}. No evidence for dark matter is found and we thus place limits on allowed parameter space. With this low-threshold detector, we are sensitive to coherent elastic scattering between dark matter and nuclei. The cross section for this process is orders of magnitude higher than for other processes historically used for accelerator-based direct-detection searches so that our small, 14.6 kg detector significantly improves on past constraints. At peak sensitivity, we reject the flux consistent with the cosmologically observed dark-matter concentration for all coupling constants α_{D}<0.64, assuming a scalar dark-matter particle. We also calculate the sensitivity of future COHERENT detectors to dark-matter signals which will ambitiously test multiple dark-matter spin scenarios.

3.
Phys Rev Lett ; 131(22): 221801, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101357

RESUMO

Using an 185-kg NaI[Tl] array, COHERENT has measured the inclusive electron-neutrino charged-current cross section on ^{127}I with pion decay-at-rest neutrinos produced by the Spallation Neutron Source at Oak Ridge National Laboratory. Iodine is one the heaviest targets for which low-energy (≤50 MeV) inelastic neutrino-nucleus processes have been measured, and this is the first measurement of its inclusive cross section. After a five-year detector exposure, COHERENT reports a flux-averaged cross section for electron neutrinos of 9.2_{-1.8}^{+2.1}×10^{-40} cm^{2}. This corresponds to a value that is ∼41% lower than predicted using the MARLEY event generator with a measured Gamow-Teller strength distribution. In addition, the observed visible spectrum from charged-current scattering on ^{127}I has been measured between 10 and 55 MeV, and the exclusive zero-neutron and one-or-more-neutron emission cross sections are measured to be 5.2_{-3.1}^{+3.4}×10^{-40} and 2.2_{-0.5}^{+0.4}×10^{-40} cm^{2}, respectively.

4.
Phys Rev Lett ; 129(8): 081801, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36053683

RESUMO

We measured the cross section of coherent elastic neutrino-nucleus scattering (CEvNS) using a CsI[Na] scintillating crystal in a high flux of neutrinos produced at the Spallation Neutron Source at Oak Ridge National Laboratory. New data collected before detector decommissioning have more than doubled the dataset since the first observation of CEvNS, achieved with this detector. Systematic uncertainties have also been reduced with an updated quenching model, allowing for improved precision. With these analysis improvements, the COHERENT Collaboration determined the cross section to be (165_{-25}^{+30})×10^{-40} cm^{2}, consistent with the standard model, giving the most precise measurement of CEvNS yet. The timing structure of the neutrino beam has been exploited to compare the CEvNS cross section from scattering of different neutrino flavors. This result places leading constraints on neutrino nonstandard interactions while testing lepton flavor universality and measures the weak mixing angle as sin^{2}θ_{W}=0.220_{-0.026}^{+0.028} at Q^{2}≈(50 MeV)^{2}.

5.
Phys Rev Lett ; 126(1): 012002, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33480779

RESUMO

We report the first measurement of coherent elastic neutrino-nucleus scattering (CEvNS) on argon using a liquid argon detector at the Oak Ridge National Laboratory Spallation Neutron Source. Two independent analyses prefer CEvNS over the background-only null hypothesis with greater than 3σ significance. The measured cross section, averaged over the incident neutrino flux, is (2.2±0.7)×10^{-39} cm^{2}-consistent with the standard model prediction. The neutron-number dependence of this result, together with that from our previous measurement on CsI, confirms the existence of the CEvNS process and provides improved constraints on nonstandard neutrino interactions.

6.
Dokl Biochem Biophys ; 484(1): 88-91, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31012023

RESUMO

The role of the nuclear protein coilin in the mechanisms of resistance of potato Solanum tuberosum cultivar Chicago to biotic and abiotic stresses was studied using the CRISPR-Cas9 technology. For the coilin gene editing, a complex consisting of the Cas9 endonuclease and a short guide RNA was immobilized on gold or chitosan microparticles and delivered into apical meristem cells by bioballistics or vacuum infiltration methods, respectively. Editing at least one allele of the coilin gene considerably increased the resistance of the edited lines to infection with the potato virus Y and their tolerance to salt and osmotic stress.


Assuntos
Resistência à Doença , Meristema , Proteínas Nucleares , Pressão Osmótica , Doenças das Plantas/virologia , Proteínas de Plantas , Rhabdoviridae/metabolismo , Solanum tuberosum , Sistemas CRISPR-Cas , Meristema/genética , Meristema/metabolismo , Meristema/virologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Solanum tuberosum/genética , Solanum tuberosum/metabolismo , Solanum tuberosum/virologia
7.
Biochemistry (Mosc) ; 83(12): 1552-1562, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30878030

RESUMO

The use of the CRISPR/Cas9 prokaryotic adaptive immune system has led to a breakthrough in targeted genome editing in eukaryotes. The CRISPR/Cas technology allows to generate organisms with desirable characteristics by introducing deletions/insertions into selected genome loci resulting in the knockout or modification of target genes. This review focuses on the current state of the CRISPR/Cas use for the generation of plants resistant to viruses, bacteria, and parasitic fungi. Resistance to DNA- and RNA-containing viruses is usually provided by expression in transgenic plants of the Cas endonuclease gene and short guide RNAs (sgRNAs) targeting certain sites in the viral or the host plant genomes to ensure either direct cleavage of the viral genome or modification of the plant host genome in order to decrease the efficiency of virus replication. Editing of plant genes involved in the defense response to pathogens increases plants resistance to bacteria and pathogenic fungi. The review explores strategies and prospects of the development of pathogen-resistant plants with a focus on the generation of non-transgenic (non-genetically modified) organisms, in particular, by using plasmid (DNA)-free systems for delivery of the Cas/sgRNA editing complex into plant cells.


Assuntos
Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Plantas/genética , Genes de Plantas/genética , Plantas/microbiologia , Plantas/parasitologia , Plantas/virologia
8.
Biochemistry (Mosc) ; 83(12): 1543-1551, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30878029

RESUMO

Capsid proteins (CPs) of (+)RNA-containing plant viruses are multifunctional proteins involved in many stages of viral infection cycle, in addition to their main function of virus capsid formation. For example, the tobamoviral CP ensures virus systemic transport in plants and defines the virus-host interactions, thereby influencing the virus host range, virus infectivity, pathogenicity, and manifestation of infection symptoms. Hordeiviruses and tobamoviruses belong to the Virgaviridae family and have rod-shaped virions with a helical symmetry; their CPs are similar in structure. However, no non-structural functions of hordeiviral CPs have been described so far. In this study, we assayed possible non-structural functions of CP from the barley stripe mosaic virus (BSMV) (hordeivirus). To do this, the genome of turnip vein clearing virus (TVCV) (tobamovirus) was modified by substituting the TVCV CP gene with the BSMV CP gene or its mutants. We found that BSMV CP efficiently replaced TVCV CP at all stages of viral infection. In particular, BSMV CP performed the role of tobamoviral CP in the long-distance transport of the chimeric virus, acted as a hypersensitive response elicitor, and served as a pathogenicity determinant that influenced the symptoms of the viral infection. The chimeric tobamovirus coding for the C-terminally truncated BSMV CP displayed an increased infectivity and was transported in plants in a form of atypical virions (ribonucleoprotein complexes).


Assuntos
Proteínas do Capsídeo/metabolismo , Hibridização Genética , Nicotiana/virologia , Tobamovirus/genética , Tobamovirus/fisiologia , Tobamovirus/metabolismo
9.
Dokl Biochem Biophys ; 479(1): 90-94, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29779105

RESUMO

The activity of the pool of sgRNA molecules designed for different regions of potato coilin and phytoene desaturase genes was compared in vitro. Due to the presence of nucleotides unpaired with DNA, sgRNA is able not only to inhibit but also to stimulate the activity of the Cas9-sgRNA complex in vitro. Although the first six nucleotides located in the DNA substrate proximally to the PAM site at the 3' end are the binding sites for cas9, they had no significant effect on the activity of the Cas9-sgRNA complex.


Assuntos
Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Genoma de Planta/genética , RNA Guia de Cinetoplastídeos/genética , Solanum tuberosum/genética , Sequência de Bases
10.
Vestn Khir Im I I Grek ; 175(5): 46-51, 2016.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-30422447

RESUMO

A comparative analysis of treatment results of fractures of long bones of the upper extremities was made in 172 victims with severe polytrauma. The traditional strategy of treatment was used in the first group. The new technologies such as prognostic tactics, method of Damage control orthopedics and low-invasive osteosynthesis developed by the authors were applied in the second group. The application of new technologies allowed doctors to improve the immediate and long-term results of surgery. The rate of lethality decreased in 1,6 times, incidence of complications reduced in 1,4 times. Hospital stay shortened in 2 times: for victims with favorable prognosis ­ on 7 days; for patients with unfavorable prognosis ­ on 13 days. The long-term results were studied in 154 (89,5%) patients. The common duration of treatment reduced on 30 days and the quantity of good results increased on 18,6%. The number of patients with vocational rehabilitation increased from 82,3 to 90,7%.


Assuntos
Tecnologia Biomédica , Fixação Interna de Fraturas , Efeitos Adversos de Longa Duração/prevenção & controle , Traumatismo Múltiplo/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Extremidade Superior/lesões , Tecnologia Biomédica/métodos , Tecnologia Biomédica/tendências , Feminino , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/tendências , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Traumatismo Múltiplo/diagnóstico , Avaliação de Processos e Resultados em Cuidados de Saúde , Prognóstico , Federação Russa , Índices de Gravidade do Trauma
11.
Bull Exp Biol Med ; 157(6): 798-803, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25342486

RESUMO

Nanoparticles of aluminum and zinc phthalocyanin and metal-free phthalocyanin (AlPc, ZnPc, and H2Pc), whose molecular forms are photosensitizers, can serve as effective "prophotosensitizers" in photodynamic therapy for malignant tumors. Transition (stimulation) of photo-inert nanoparticles into a photoactive photosensitizer is realized locally in the tumor node by its exposure to potent laser pulses. Systemic injection of AlPc, ZnPc, and H2Pc nanoparticles has not led to accumulation of their photoactive form in the skin, which can lead to the development of skin phototoxicity. Effective protocols of photodynamic therapy with ZnPc nanoparticles are determined. The use of these protocols in mice with S-37 sarcoma led to 92-70% tumor growth inhibition, 48% improvement of survival, and cure in 84% cases.


Assuntos
Indóis/uso terapêutico , Terapia a Laser/métodos , Nanoestruturas/uso terapêutico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Sarcoma/tratamento farmacológico , Sarcoma/radioterapia , Animais , Compostos Azo , Feminino , Fluorescência , Imidazóis , Isoindóis , Camundongos , Compostos Organometálicos , Compostos de Zinco
12.
Zh Vopr Neirokhir Im N N Burdenko ; 78(5): 57-63; discussion 63, 2014.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-25406909

RESUMO

Authors show an example of a successful treatment of a patient with a giant intracranial hemangiopericytoma. Hemangiopericytoma are aggressive tumors with a high rate of recurrence and metastasis. Despite the malignant nature of these tumors often reach a large size with minor clinical signs. Surgical removal of the tumor is still the primary method of treatment.


Assuntos
Neoplasias Encefálicas/cirurgia , Hemangiopericitoma/cirurgia , Adulto , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patologia , Hemangiopericitoma/diagnóstico , Hemangiopericitoma/patologia , Humanos , Masculino
13.
Artigo em Russo | MEDLINE | ID: mdl-36843468

RESUMO

OBJECTIVE: To study the intellectual activity of children and adolescents with progressive forms of schizophrenia using quantitative and qualitative diagnostic methods. MATERIAL AND METHODS: An experimental group consisted of 67 children and adolescents (mean age 11.1±2.8 years) with mental pathology of schizophrenia spectrum with varying severity of the disease (malignant, progressive, and low progressive course) and leading clinical syndromes (catatonic, psychopathic, neurosis-like, and hyperkinetic). A control group included 63 children and adolescents (mean age 11.1±3.0 years) without a verified psychiatric diagnosis, secondary schools' students. The Wechsler Intelligence Scale for Children (WISC) was used for assessing intelligence, the Design of objects method was used for assessing the characteristics of thinking. RESULTS: The relationship between thinking disorders and the parameters of verbal intelligence in patients with schizophrenia was shown (the Information subtest is related to all Object Construction parameters, r=0.401 to r=0.634; verbal IQ score is associated with some Object Construction scores, r=0.541 to r=0.537). In the control group, such a relationship was not noted. A decrease in the level of intelligence and severe thinking disorders is associated with such clinical factors as the malignant course of the disease (mean Full IQ score is 60.1, z-value of the coefficient of standardization in relation to the age norm is -2.1) and catatonic syndrome (mean Full IQ score is 68.1, coefficient of standardization is 60%). CONCLUSION: The use of psychometric and pathopsychological approaches in the diagnosis of intellectual activity complements each other.


Assuntos
Esquizofrenia , Humanos , Criança , Adolescente , Psicometria , Esquizofrenia/diagnóstico , Inteligência , Escalas de Wechsler
14.
Vestn Khir Im I I Grek ; 168(3): 52-6, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19663281

RESUMO

The work presents a method of complex evaluation of homeostasis in patients with degenerative-dystrophic diseases of the hip joints after total endoprosthesis on the basis of mathematical integration of different laboratory indices allowing objective assessment of the state of the regulatory-metabolic status of the patient after operation of endoprosthesis, detection of disturbances of adaptive reaction to the operative trauma and, thus, prevision of the development of postoperative complications. The integral characterization is given of the periods of postaggression reaction using the proposed method. The interval of integral indices is determined which is characteristic of non-complicated postoperative period, depending on the time since the moment of operation.


Assuntos
Artroplastia de Quadril/métodos , Homeostase/fisiologia , Osteoartrite do Quadril/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Modelos Teóricos , Osteoartrite do Quadril/cirurgia , Período Pós-Operatório , Prognóstico , Estudos Retrospectivos , Adulto Jovem
15.
Vestn Khir Im I I Grek ; 168(1): 66-70, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19432151

RESUMO

Traumatologic emergency to patients with primary unstable, comminuted, intraarticular fractures of distal metaepiphysis of the radial bone (DMRB) should be provided in steady-state conditions, using reliable methods of reposition and retention of the fixed bone fragments. The strategy of treatments of fractures of DMRB first consisting in closed reposition and in surgery in case of failure or secondary displacement is thought to be outdated. In patients with symptoms of unstable fractures active surgical strategy should be used before complications appear.


Assuntos
Fixação de Fratura/métodos , Fraturas do Rádio/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Placas Ósseas , Epífises/diagnóstico por imagem , Epífises/lesões , Epífises/cirurgia , Feminino , Seguimentos , Fixação Interna de Fraturas/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Fraturas do Rádio/diagnóstico por imagem , Estudos Retrospectivos , Índices de Gravidade do Trauma , Adulto Jovem
16.
Vestn Khir Im I I Grek ; 167(6): 52-4, 2008.
Artigo em Russo | MEDLINE | ID: mdl-19241817

RESUMO

A method of blocking intramedullary osteosynthesis of metaphyseal fractures of the humeral bone is proposed. Its special features are: retrograde implantation of a nail from the antecubital fossa of the humeral bone, blocking the nail with distal blocking screws and proximal blocking screws which are fixed in the nail at the expense of threaded connection. This method gives exact reposition, absolute stability of fixation, possibility of early load and rehabilitation.


Assuntos
Fixação Intramedular de Fraturas/métodos , Fraturas do Úmero/cirurgia , Adulto , Feminino , Seguimentos , Consolidação da Fratura , Humanos , Fraturas do Úmero/diagnóstico por imagem , Pessoa de Meia-Idade , Radiografia
17.
Vestn Khir Im I I Grek ; 167(6): 55-8, 2008.
Artigo em Russo | MEDLINE | ID: mdl-19241818

RESUMO

An analysis of treatment of 95 patients allowed the authors believe that antegrade blocking osteosynthesis gives a reliable fixation of fragments in cases of fractures of distal metaphysic of the femoral bone and prevents the development of extension contracture in the knee joint. It gives a good functional result.


Assuntos
Fraturas do Fêmur/cirurgia , Fixação Intramedular de Fraturas/instrumentação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Parafusos Ósseos , Feminino , Fraturas do Fêmur/diagnóstico por imagem , Seguimentos , Consolidação da Fratura , Humanos , Fixadores Internos , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
18.
Vestn Khir Im I I Grek ; 167(1): 43-7, 2008.
Artigo em Russo | MEDLINE | ID: mdl-18411667

RESUMO

The proposed method of reposition and polyaxial stabilization of fragments for intramedullary meallosynthesis of fractures of long tubular bones allows blocking osteosynthesis to be successfully used in treatment of complex metaphyseal fractures of shin bones. It results in strong fixation of the fragments, makes it possible to successfully eliminate residual deformities after introduction of the nail and to avoid the development of them in future under the influence of loading. The method provides early functioning of the interfacing joints, early axial loading, shorter period of disability, the absence of external immobilization.


Assuntos
Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Contenções , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Diáfises/lesões , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Zh Nevrol Psikhiatr Im S S Korsakova ; 118(5. Vyp. 2): 3-11, 2018.
Artigo em Russo | MEDLINE | ID: mdl-30141781

RESUMO

The article discusses a systematic clinical and psychological approach to different types of impaired cognitive development in children and adolescents with mental disorders in the context of the concept of cognitive dysontogenesis. The authors describe the types of cognitive dysontogenesis in schizophrenic and autistic spectrum disorders and present two models of its estimation: with complex psychometric and pathopsychological diagnosis and with a support on pathopsychological diagnosis of cognitive development only. Special attention is paid to domestic techniques developed in MHRC, which classify the types of cognitive dysontogenesis in children and adolescents with different disorders of mental development without reliance on psychometric indicators. The developed model of cognitive development profiles allows to make a conclusion about a typical picture of cognitive disorders in different versions of mental pathology.


Assuntos
Transtorno do Espectro Autista , Transtornos Globais do Desenvolvimento Infantil , Transtornos Cognitivos , Adolescente , Transtorno do Espectro Autista/diagnóstico , Criança , Transtornos Globais do Desenvolvimento Infantil/diagnóstico , Cognição , Transtornos Cognitivos/diagnóstico , Humanos
20.
Vestn Khir Im I I Grek ; 166(1): 25-9, 2007.
Artigo em Russo | MEDLINE | ID: mdl-17672103

RESUMO

The blocked intramedullary osteosynthesis of tubular bones, including the cases with multiple and combined traumas, is an up-to-date and minimally traumatic method that allows durable stabilization and dynamic fixation of complex fractures. Our results show high efficiency of this minimally traumatic method since it gives high stability of osteosynthesis, early functioning of adjoining joints, early axis loading, shorter period of disablement, the absence of external immobilization. Perfection of the technology and design of the nails allows successful use of the method for metaphysis localizations.


Assuntos
Fixação Intramedular de Fraturas/métodos , Fraturas Ósseas/classificação , Fraturas Ósseas/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fraturas Ósseas/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Índice de Gravidade de Doença
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