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1.
Phys Chem Chem Phys ; 22(39): 22501-22507, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32996959

RESUMO

We explore the unusual nature of chemical bonding of thorium atoms with a ring of six carbon atoms (hexagon) in novel carbon materials. Our ab initio calculations of Th-based metallofullerenes (Th@C60 and Th@C20) and Th bound to benzene or coronene at the Hartree-Fock level with the second order perturbation (MP2) correction accounting for the van der Waals interactions demonstrate that the optimal position of the thorium atom is where it faces the center of a hexagon and is located at a distance of 2.01-2.07 Å from the center. For Th encapsulated in C60 it is found at 2.01 Å, whereas the other local energy minima are shifted to larger energies (0.22 eV and higher). Inside C60 the highest local minimum at 1.17 eV is observed when Th faces the center of the five member carbon ring (pentagon). Based on our calculations for Th with benzene and coronene where the global minimum for Th corresponds to its position at 2.05 Å (benzene) or 2.02 Å (coronene) from the hexagon center, we conclude that a well pronounced minimum is likely to be present in graphene and in a single wall carbon nanotube. The ground state of Th is singlet, and other high spin states (triplet and quintet) lie higher in energy (>1.62 eV). We discuss a potential use of carbon nanomaterials with the 229Th isotope having its nuclear transition in the optical range, for metrological purposes.

2.
Stomatologiia (Mosk) ; 99(4): 33-42, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32692517

RESUMO

One of the most common abnormalities in the development of the jaw is the narrowing of the alveolar process of the maxilla. In childhood, the elimination of such a deformation is quite common. But with age, the only effective option is the inclusion of a surgical procedure in the rehabilitation plan. The medial and parasagittal osteotomy of the maxilla for the purpose of its expansion by a distraction device has a number of important nuances which can significantly affect the result. These include: localization of sagittal osteotomy of the palate and alveolar process; the direction of cutting the walls of the maxillary sinus; type of fixation of the device (dental-borne or bone-borne). The article summarizes the experience of 74 surgical-associated expansions of the jaws with asymmetric deformations performed over 2 years. A retrospective analysis according to cone beam computed tomography is given. of complex treatment with the inclusion of sparing osteotomy of the maxilla in the rehabilitation plan and a differentiated approach to performing surgical manipulation allow to achieve optimal aesthetic and functional results and to correct the asymmetry to the greatest extent.


Assuntos
Osteogênese por Distração , Técnica de Expansão Palatina , Processo Alveolar , Maxila , Osteotomia de Le Fort , Estudos Retrospectivos
3.
Dokl Biochem Biophys ; 490(1): 12-15, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32342304

RESUMO

The effect of stilbene polyphenols (resveratrol and pinosilvin) and flavonoids (dihydromyricetin, epigallocatechin, and dihydroquercetin) on producing the reactive oxygen species (ROS) due to cell respiration using the isolated mitochondria of the fungus Dipodascus (Endomyces) magnusii was studied. It was shown that the inhibition of the ROS generation with stilbenes is related to both the oxygen consumption inhibition and their antioxidant properties. The degree of manifestation of polyphenol antioxidant properties depended on the number of hydroxyl groups in a polyphenol molecule. Of the flavonoids tested, dihydromyricetin was most active in reducing the ROS generation, but its inhibitory effect on oxygen consumption by mitochondria was significantly lower as compared to that of the stilbenes. The data obtained show that the mechanism of reducing the ROS generation with polyphenols is associated with both the respiratory inhibition and their antioxidant properties.


Assuntos
Flavonoides/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Polifenóis/farmacologia , Saccharomycetales/metabolismo , Estilbenos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Catequina/análogos & derivados , Catequina/química , Catequina/farmacologia , Flavonoides/química , Flavonóis/química , Flavonóis/farmacologia , Testes de Sensibilidade Microbiana , Consumo de Oxigênio , Polifenóis/química , Quercetina/análogos & derivados , Quercetina/química , Quercetina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Resveratrol/química , Resveratrol/farmacologia , Estilbenos/química
4.
Dokl Biochem Biophys ; 481(1): 201-204, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30168059

RESUMO

A new recombinant strain of Yarrowia lipolytica synthesizing encapsulated highly thermostable phytase of Obesumbacterium proteus, which is recommended for use as a premix component of feed compositions in animal husbandry, was obtained.


Assuntos
6-Fitase/biossíntese , DNA Recombinante/genética , Enterobacteriaceae/enzimologia , Yarrowia/genética , Yarrowia/metabolismo , 6-Fitase/química , Sequência de Aminoácidos , Cápsulas , Estabilidade Enzimática , Temperatura
5.
Stomatologiia (Mosk) ; 96(5): 48-55, 2017.
Artigo em Russo | MEDLINE | ID: mdl-29072647

RESUMO

The study objective was to compare the biomechanics of surgically assisted rapid palatal expansion (SARPE) with tooth-borne and bone-borne expanders. Materials include a sample of 54 cone-beam CT of 27 patients who underwent SARPE (bone-borne, n=21; tooth-borne, n=6) before treatment and at expander removal. Expansion efficacy was estimated by interapecal and intercoronal distances between maxillary canines, premolars and first molars as well as Coronal-Apical Index (CAI = coronal expansion (mm)/apical expansion (mm)). CAI varied between 1.5 and 2.0 in the group of patients with bone-borne appliances, and from 2.3 to 2.6 in the tooth-borne appliances group. The maximal amount of vestibular coronal declination was revealed in premolars by the use of tooth-borne appliances. Bone-borne appliances allowed lateralization of maxilla and the most prominent effect of tooth shift in a vestibular direction, which may be seen as the most important factors in a relapse prevention.


Assuntos
Dente Pré-Molar/cirurgia , Dente Canino/cirurgia , Fixadores Externos , Fixadores Internos , Dente Molar/cirurgia , Osteogênese por Distração/instrumentação , Técnica de Expansão Palatina , Dente Pré-Molar/diagnóstico por imagem , Fenômenos Biomecânicos , Tomografia Computadorizada de Feixe Cônico , Dente Canino/diagnóstico por imagem , Humanos , Dente Molar/diagnóstico por imagem
6.
Dokl Biochem Biophys ; 470(1): 349-352, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27817013

RESUMO

This article presents the characteristics of the highly inducible promoter of the gene encoding the mitochondrial porin, the voltage-dependent anion channel (VDAC). This promoter is recommended for use in new genetic constructs both in basic research for assessing the adaptive strategy of lower eukaryotes under adverse conditions and in designing new highly competitive transformants producing economically important compounds (proteins, lipids, and organic acids) on its basis.


Assuntos
Regiões Promotoras Genéticas , Canais de Ânion Dependentes de Voltagem/genética , Yarrowia/genética , Meios de Cultura/química , Técnicas de Transferência de Genes , Genes Reporter , Engenharia Genética/métodos , Vetores Genéticos , Genoma , Peróxido de Hidrogênio/farmacologia , Concentração de Íons de Hidrogênio , Óperon Lac , Estresse Fisiológico , Canais de Ânion Dependentes de Voltagem/metabolismo , Yarrowia/efeitos dos fármacos , Yarrowia/metabolismo , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
7.
Stomatologiia (Mosk) ; 95(4): 49-52, 2016.
Artigo em Russo | MEDLINE | ID: mdl-27636762

RESUMO

The article considers stages of complex rehabilitation treatment plans of patients with bite anomalies. The study included 515 patients with various complex malocclusions. Two and conventional three stage treatment plans are described. The article suggests indications for the two stage treatment protocol. The evaluation of efficiency and stability of achieved treatment results obtained with a help of the system of quantitative analysis of dentooralfacial disorders is presented.


Assuntos
Má Oclusão/reabilitação , Má Oclusão/cirurgia , Adulto , Feminino , Humanos
8.
Dokl Biochem Biophys ; 468(1): 190-2, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27417717

RESUMO

A modified variant of the ß-galactosidase gene from Escherichia coli (lacZ) has been obtained. This was designed for building transcriptional reporter constructs, the product of which possesses a higher proteolytic resistance in the Yarrowia lipolytica yeasts. The study of the activity of mitochondrial voltagedependent porin (voltage-dependent anion channel, VDAC) showed a high efficiency of the reporter system based on the designed lacZ reporter compared to the wild-type lacZ gene.


Assuntos
Proteínas de Escherichia coli/genética , Genes Reporter , Engenharia Genética/métodos , Óperon Lac , Yarrowia/genética , beta-Galactosidase/genética , Escherichia coli , Proteínas de Escherichia coli/metabolismo , Vetores Genéticos , Concentração de Íons de Hidrogênio , Reprodutibilidade dos Testes , Canais de Ânion Dependentes de Voltagem/genética , Canais de Ânion Dependentes de Voltagem/metabolismo , Yarrowia/metabolismo , beta-Galactosidase/metabolismo
9.
J Chem Phys ; 145(1): 014101, 2016 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-27394093

RESUMO

In order to increase the accuracy of the linearized augmented plane wave (LAPW) method, we present a new approach where the plane wave basis function is augmented by two different atomic radial components constructed at two different linearization energies corresponding to two different electron bands (or energy windows). We demonstrate that this case can be reduced to the standard treatment within the LAPW paradigm where the usual basis set is enriched by the basis functions of the tight binding type, which go to zero with zero derivative at the sphere boundary. We show that the task is closely related with the problem of extended core states which is currently solved by applying the LAPW method with local orbitals (LAPW+LO). In comparison with LAPW+LO, the number of supplemented basis functions in our approach is doubled, which opens up a new channel for the extension of the LAPW and LAPW+LO basis sets. The appearance of new supplemented basis functions absent in the LAPW+LO treatment is closely related with the existence of the u̇l-component in the canonical LAPW method. We discuss properties of additional tight binding basis functions and apply the extended basis set for computation of electron energy bands of lanthanum (face and body centered structures) and hexagonal close packed lattice of cadmium. We demonstrate that the new treatment gives lower total energies in comparison with both canonical LAPW and LAPW+LO, with the energy difference more pronounced for intermediate and poor LAPW basis sets.

10.
Stomatologiia (Mosk) ; 95(1): 40-43, 2016.
Artigo em Russo | MEDLINE | ID: mdl-26925565

RESUMO

The purpose of the study was to assess the changes in the width and quality of keratinized tissue created in the area of vestibuloplasty on the lower jaw. Preliminary results of the study showed that autotransplantation method allows creating proper buffer zone with the desired mucosa thickness and is particularly justified in cases of "washing board" effect. However, the method is technically more demanding and is more expensive and painfull for patients. The use of alternative materials of artificial origin, such as "Mucograft" and "Tachocomb" simplifies the execution of operation, thereby reducing operational risk, but often does not lead to the formation of a fully keratinized gingiva.


Assuntos
Gengiva/cirurgia , Queratinas , Mandíbula/cirurgia , Palato Duro , Retalhos Cirúrgicos , Vestibuloplastia/métodos , Adolescente , Adulto , Aloenxertos , Autoenxertos , Feminino , Gengiva/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Palato Duro/cirurgia , Adulto Jovem
11.
Stomatologiia (Mosk) ; 95(6): 36-39, 2016.
Artigo em Russo | MEDLINE | ID: mdl-28139590

RESUMO

The purpose of the message was the comparison of change in the width and quality of keratinized tissue created in the lower vestibuloplasty area. Preliminary results of the case-control study involving 71 patients showed that autotransplantation managed to create the necessary buffer zone with the desired thickness of the mucosa and is particularly justified in cases of «washing board effect¼. However, the method is technically complicated and more expensive and painfull for patients. The use of alternative materials of artificial origin, such as «Mucograft¼ and bloodstatic and desinfecting sponge simplifies the procedure technique thereby reducing operational risk but often does not lead to the formation of a fully keratinized gingiva.


Assuntos
Analgésicos/uso terapêutico , Emoções , Hipnóticos e Sedativos/uso terapêutico , Mandíbula/cirurgia , Dor Pós-Operatória/tratamento farmacológico , Ferida Cirúrgica/terapia , Vestibuloplastia/efeitos adversos , Técnicas de Fechamento de Ferimentos/psicologia , Adulto , Bandagens , Estudos de Casos e Controles , Feminino , Retalhos de Tecido Biológico , Gengiva/fisiologia , Gengiva/cirurgia , Hemostasia Cirúrgica/métodos , Humanos , Queratinas/metabolismo , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/transplante , Período Pós-Operatório , Cuidados Pré-Operatórios , Transplante Autólogo/métodos , Vestibuloplastia/psicologia , Adulto Jovem
12.
Biochemistry (Mosc) ; 76(7): 761-73, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21999537

RESUMO

Leishmania are a genus of sandfly-transmitted protozoan parasites that cause a spectrum of debilitating and often fatal diseases in humans throughout the tropics and subtropics. During the parasite life cycle, Leishmania survive and proliferate in highly hostile environments. Their survival strategies involve the formation of an elaborate and dense cell-surface glycocalyx composed of diverse stage-specific glycoconjugates that form a protective barrier. Phosphoglycans constitute the variable structural and functional domain of major cell-surface lipophosphoglycan and secreted proteophosphoglycans. In this paper, we discuss structural aspects of various phosphoglycans from Leishmania with the major emphasis on the chemical preparation of neoglycoconjugates (neoglycoproteins and neoglycolipids) based on Leishmania lipophosphoglycan structures as well as the immunological evaluation for some of them as potential anti-leishmaniasis vaccines.


Assuntos
Glicoconjugados/química , Leishmania/química , Leishmania/imunologia , Vacinas contra Leishmaniose/química , Vacinas Sintéticas/química , Sequência de Carboidratos , Glicoconjugados/síntese química , Glicoconjugados/imunologia , Glicoesfingolipídeos/síntese química , Leishmaniose/imunologia , Dados de Sequência Molecular , Toxina Tetânica/química
13.
Vopr Onkol ; 57(1): 99-101, 2011.
Artigo em Russo | MEDLINE | ID: mdl-21598717

RESUMO

Combined treatment for colorectal cancer involving preoperative hypooxyradiotherapy was used to boost targeted irradiation of tumor cells. End results were significantly improved due to the decrease in the number of distant metastases even in cases of poor prognosis because of lymph node involvement.


Assuntos
Hipóxia Celular , Neoplasias Colorretais/radioterapia , Neoplasias Colorretais/cirurgia , Terapia Neoadjuvante/métodos , Radioterapia Adjuvante/métodos , Adulto , Idoso , Neoplasias Colorretais/patologia , Feminino , Seguimentos , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasia Residual/diagnóstico , Radioterapia Adjuvante/efeitos adversos , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
14.
Khirurgiia (Mosk) ; (3): 41-3, 2011.
Artigo em Russo | MEDLINE | ID: mdl-21423107

RESUMO

Results of treatment of 298 patients with colon cancer in the absence of distant metastases were analyzed. The long-term follow-up results were obtained after up to 20 years; 10 years follow-up results were obtained in 95% of the operated patients. The survival rate was significantly dependant on the stage of the disease, i.e., on the presence of regional lymph nodes invasion. Authors conclude, that possibilities of surgical treatment in further improvement of survival rates are to certain limited and exhausted. Therefore, further workout of perioperative combined chemo- and radiotherapy of patients with colon cancer is expected to improve the results.


Assuntos
Adenocarcinoma/cirurgia , Colectomia , Neoplasias do Colo/cirurgia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Idoso , Neoplasias do Colo/mortalidade , Neoplasias do Colo/patologia , Seguimentos , Humanos , Estadiamento de Neoplasias , Estudos Retrospectivos , Federação Russa/epidemiologia , Taxa de Sobrevida/tendências , Fatores de Tempo , Resultado do Tratamento
15.
Vopr Onkol ; 56(1): 66-9, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20361619

RESUMO

The report discusses our 30-year experience with surgical and combined treatment of rectal cancer. In cases of preoperative radiotherapy, loco-regional frequency of relapse dropped to 9.6% as compared with surgery (16.3%). After preoperative thermoradiotherapy it fell to 4.6%; polyradiomodification - 0.5% (3-year follow-up). Distant metastasis formation rates were: after polyradiomodification--1.5%, radiotherapy--9.6%, and thermo-radiotherapy--6%. Recurrence-free survival rates (3 years) were: polyradiomodification--97.3%, thermo-radiotherapy--75.9%, radiotherapy--71.1%, and surgery--58%. Data on regimens and dosage of polyradiomodification alongside radiation damage for different combinations of treatment are presented.


Assuntos
Terapia Neoadjuvante/métodos , Recidiva Local de Neoplasia/prevenção & controle , Neoplasias Retais/radioterapia , Neoplasias Retais/cirurgia , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Hipertermia Induzida , Masculino , Pessoa de Meia-Idade , Radioterapia Adjuvante/métodos , Neoplasias Retais/patologia , Estudos Retrospectivos , Resultado do Tratamento
16.
Vopr Onkol ; 54(3): 350-3, 2008.
Artigo em Russo | MEDLINE | ID: mdl-18652242

RESUMO

The paper presents an evaluation of the results of surgical and combined treatment received by 961 patients at the Center's Clinics within 28 years. The analysis was based on 3 protocols of prospective randomized study. It dealt with assessment of the end results of surgical and combined treatment for operable rectal cancer using one preoperative hyperfractonated STD of 5-25 Gy. That was combined with local microwave hyperthermia and two radio modifiers--local microwave hyperthermia+intrarectal administration of a preparation containing metronidazolum. Due to the latter factor, the rate of 3-year relapse-free survival rose considerably. Also, loco-regional and distant metastasis incidence was cut down due to superior ablasticity of surgery.


Assuntos
Neoplasias Retais/mortalidade , Neoplasias Retais/terapia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Taxa de Sobrevida
17.
Vopr Virusol ; 53(2): 40-3, 2008.
Artigo em Russo | MEDLINE | ID: mdl-18450109

RESUMO

The investigation demonstrated that influenza A and B viruses actively interacted with a sorbent obtained from modified oxygen-containing graphite via hydrothermal treatment irrespective of the antigenic structure of surface proteins. Virionic sorption occurred in a wide range of temperatures from 8 to 34 degrees C for 15 min or more. After interaction with the sorbent, the titer of a virus decreased 4- to 256-fold. The immobilized viruses were able to interact with homologous antibodies and immune sera. Desorption of viruses with the sorbent was extremely slight. In addition to viruses, the proteins of nonviral nature--those of allantoic hen embryo liquid, immune serum, and 1% bovine serum albumin--could be immobilized to the sorbent.


Assuntos
Grafite/metabolismo , Vírus da Influenza A Subtipo H1N1/metabolismo , Vírus da Influenza A Subtipo H3N2/metabolismo , Vírus da Influenza B/metabolismo , Absorção , Anticorpos Antivirais/imunologia , Especificidade de Anticorpos , Grafite/química , Soros Imunes/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza B/imunologia , Oxigênio , Temperatura , Fatores de Tempo
19.
Artigo em Inglês | MEDLINE | ID: mdl-17573628

RESUMO

The article is devoted to the theoretical aspects of the development of the effective method for the removal of protein-bound uremic toxins. It is shown that the methods of flow and differential scanning microcalorimetry are sufficient enough for the evaluation of the degree of ligand loading of human serum albumin with protein-bound uremic toxins. The molecules of albumin isolated from blood plasma of the patients being kept on chronic dialysis are demonstrating significant alterations of conformation and complex-forming properties, the correction of which by conventional methods of extracorporeal detoxification (exhaustive dialysis, treatment on synthetic SCN carbons) are practically ineffective. Deliganding of uremic albumin may be successfully performed on conventional carbon haemosorbents upon preliminary separation of blood plasma and its dilution with acetate buffer 1:1 at pH = 5.08. Treatment of the whole blood of patients onto new mass-fractal deliganding carbon, i.e., hemosorbents of HSGD trademark. These HSGD haemosorbents quite effectively could be used for restoration of main parameters of uremic HAS molecules conformation and ligand-binding activity simultaneously with hemodialysis upon the protection by locally performed citrate anticoagulation as an easier and cheaper method for the removal of protein-bound uremic toxins.


Assuntos
Carvão Vegetal/química , Carvão Vegetal/uso terapêutico , Albumina Sérica/efeitos dos fármacos , Toxinas Biológicas/sangue , Toxinas Biológicas/química , Uremia/sangue , Uremia/tratamento farmacológico , Adsorção , Sítios de Ligação , Varredura Diferencial de Calorimetria/métodos , Carvão Vegetal/metabolismo , Furanos/sangue , Hemoperfusão , Hipuratos/sangue , Humanos , Concentração de Íons de Hidrogênio , Indicã/sangue , Membranas Artificiais , Plasma/metabolismo , Propionatos/sangue , Ligação Proteica , Valores de Referência , Diálise Renal/métodos , Albumina Sérica/metabolismo , Resultado do Tratamento
20.
Vopr Onkol ; 52(5): 521-4, 2006.
Artigo em Russo | MEDLINE | ID: mdl-17168359

RESUMO

Use of combined pre- and intraoperative radiotherapy for rectal cancer involving metastases to regional lymph nodes failed to lower incidence of loco-regional recurrences or improve 5-year results, as compared with pre-operative radiotherapy alone. Besides, distant metastasis rates remained rather high (ca.30%). However, pre-operative radiotherapy plus local SHF-hyperthermia were followed by a significant drop in loco-regional recurrence incidence (to 2.3%), as compared with surgery alone and combined treatment using pre-operative hyper-fractionated-radiotherapy (TTD 25 Gy). Distant metastasis rates dropped to 25%. Also, 5-year survival increased significantly.


Assuntos
Hipertermia Induzida , Linfonodos/patologia , Terapia Neoadjuvante/métodos , Neoplasias Retais/radioterapia , Neoplasias Retais/cirurgia , Fracionamento da Dose de Radiação , Feminino , Seguimentos , Humanos , Período Intraoperatório , Metástase Linfática , Masculino , Recidiva Local de Neoplasia/prevenção & controle , Estadiamento de Neoplasias , Radioterapia Adjuvante , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
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