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1.
Sci Rep ; 7(1): 12405, 2017 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-28963519

RESUMO

We make use of the physical mechanism of proton pumping in the so-called Complex I within mitochondria membranes. Our model is based on sequential charge transfer assisted by conformational changes which facilitate the indirect electron-proton coupling. The equations of motion for the proton operators are derived and solved numerically in combination with the phenomenological Langevin equation describing the periodic conformational changes. We show that with an appropriate set of parameters, protons can be transferred against an applied voltage. In addition, we demonstrate that only the joint action of the periodic energy modulation and thermal noise leads to efficient uphill proton transfer, being a manifestation of stochastic resonance.


Assuntos
Complexo I de Transporte de Elétrons/química , Membranas Mitocondriais/metabolismo , Mitocôndrias/metabolismo , Prótons
2.
Kardiologiia ; 56(10): 5-12, 2016 10.
Artigo em Russo | MEDLINE | ID: mdl-28290889

RESUMO

OBJECTIVE: to investigate relationship between activity of platelet nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP) dependent dehydrogenases in patients with ischemic heart disease (IHD) after coronary artery bypass grafting (CABG) and their sensitivity to clopidogrel. MATERIAL AND METHODS: We studied 51 male patients with chronic IHD before and after CABG. Control group comprised 35 healthy men. In IHD patients spontaneous and induced platelet aggregation was measured by aggregometry before CABG (in 2 weeks after cessation of antiplatelet drugs), after CABG during therapy with clopidogrel (75 mg/day), and in 6 months after surgery. Patients were classified as clopidogrel sensitive or resistant using cutoff of 50% inhibition of initial ADP (5 M) induced platelet aggregation after 2 weeks of treatment with clopidogrel. Activity of platelet NAD and NADP dependent dehydrogenases was measured by bioluminescent method. RESULTS: There were 41 clopidogrel sensitive and 10 clopidogrel resistant patients. Irrespective of sensitivity to clopidogrel platelet metabolism in IHD patients was characterized by reduced activity of anaerobic energetics, glutathione-dependent antioxidant system, reactions that transport products of lipid catabolism on glycolysis, and NADPH-dependent transfer of substrates from citric acid cycle to amino acid metabolism. Metabolic features of platelets characteristic of clopidogrel resistance were low activity of the key reaction of pentose phosphate cycle reflecting state of plastic metabolism, and substrate flow in the tricarbonic acid cycle - determinant of intensity of aerobic energy. Clopidogrel-sensitive patients had increased platelets NADP-malate dehydrogenase activity (the key reaction of lipid anabolism).


Assuntos
Plaquetas/metabolismo , Doença da Artéria Coronariana/sangue , Inibidores da Agregação Plaquetária/farmacologia , Ticlopidina/análogos & derivados , Idoso , Plaquetas/efeitos dos fármacos , Clopidogrel , Ponte de Artéria Coronária , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/cirurgia , Resistência a Medicamentos , Humanos , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/uso terapêutico , Testes de Função Plaquetária , Ticlopidina/farmacologia , Ticlopidina/uso terapêutico
3.
Zh Nevrol Psikhiatr Im S S Korsakova ; 112(2 Pt 2): 47-51, 2012.
Artigo em Russo | MEDLINE | ID: mdl-22677679

RESUMO

The aim of this study was to evaluate macular ganglion cell complex (GCC) characteristics and peripapillary retinal nerve fiber layer (RNFL) thickness in patients with multiple sclerosis (MS) and to investigate the associations between these parameters and clinical characteristics of patients for evaluation perspectives of using this method for monitoring of disability and neurodegenerative processes. We examined a total of 113 participants (analysis of 211 eyes), divided into three groups: 1. 48 MS patients (66 eyes) with a history of optic neuritis (ON); 2. 35 MS patients (70 eyes) without a history of ON; 3. 30 disease-free control subjects (45 eyes). The estudy included anamnesis collection, neurological examination with assessment of EDSS scores. Refracted visual acuity prior to optical coherence tomography (OCT) was tested. RTVue-100 ОСТ system was used to assess peripapillary RNFL thickness and macular inner parameter (protocol GCC). The strongly correlated decline of the most RNFL and GCC indices was characteristic of all groups of MS patients with and without ON compared to controls. The damage of GCC was greater in patients with ON. The inverse correlation was found between the indices studied and the level of patient's disability. The study of GCC and RNFL thickness can be used to describe and characterize the level of axonal damage in MS and for objectification of neurodegenerative process in studies on neuroprotection and neuroreparation.


Assuntos
Esclerose Múltipla/patologia , Fibras Nervosas/patologia , Disco Óptico/patologia , Células Ganglionares da Retina/patologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia de Coerência Óptica
4.
Med Oncol ; 29(2): 1093-101, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21503826

RESUMO

Important characteristics of chronic lymphocytic leukaemia (CLL) cells are biased immunoglobulin variable heavy chain (IGHV) gene repertoire and expression of stereotyped B-cell receptors (BCRs); however, their prognostic value (in contrast to the impact of IGHV gene mutational status) is less clear. To evaluate the impact of separate IGHV gene usage and expression of stereotyped BCRs in CLL prognosis. Clinical data and IGHV gene configuration were analysed in 319 consecutive patients with CLL. We found that the majority of clinical parameters of patients were defined by IGHV mutational status. Our data also provided new evidence supporting the prognostic relevance of separate IGHV genes or stereotyped BCR in CLL, namely: (a) a restricted non-mutated (UM) IGHV gene repertoire in CLL patients with autoimmune haemolytic anaemia (AIHA) (more frequent expression of UM IGHV1-69, IGHV3-11 and IGHV4-59 genes, P = 0.001), a shorter period of AIHA development for expressors of these genes (P = 0.001) and a tendency towards expression of a stereotypic HCDR3 (P = 0.029), (b) a high incidence of second solid tumour development in IGHV3-21-expressing patients (P = 0.005) and (c) differences in overall survival (OS) of UM CLL patients depending on the BCR structure. Further research of specific IGHV gene usage and subsets of stereotyped BCRs in CLL may be helpful in more precise prediction of CLL prognosis in individual patients.


Assuntos
Rearranjo Gênico , Genes de Cadeia Pesada de Imunoglobulina , Região Variável de Imunoglobulina/genética , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/mortalidade , Receptores de Antígenos de Linfócitos B/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alcaloides de Berberina , Estudos de Coortes , Feminino , Seguimentos , Humanos , Leucemia Linfocítica Crônica de Células B/terapia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fenantridinas , Prognóstico , Taxa de Sobrevida
5.
Vestn Oftalmol ; 128(6): 6-14, 2012.
Artigo em Russo | MEDLINE | ID: mdl-23367754

RESUMO

Special characteristics of volumetric acoustic digital images of different vitreous and hyaloid membrane changes were studied based on the analysis of results of ultrasound spatial examination of young healthy adults (30 patients) and patients with posterior hyaloid membrane detachment (329 patients). Morphological features of vitreous are presented considering topography and its acoustical structure. Spatial characteristics of planar and volumetric images are determined, special acoustic signs are revealed for normal vitreous and in different changes of posterior hyaloid membrane. These presentations are compared with earlier characterized changes of detached hyaloid membrane. Structural changes of vitreous resulted from posterior hyaloid membrane rapture after blunt trauma or total lens dislocation are estimated.


Assuntos
Imageamento Tridimensional , Descolamento Retiniano/diagnóstico , Corpo Vítreo/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassonografia , Corpo Vítreo/patologia
7.
Exp Oncol ; 29(3): 226-30, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18004251

RESUMO

UNLABELLED: THE AIM of the study was to evaluate the frequency of IGHV3-21 gene usage and its clinical significance for patients with B-cell chronic lymphocytic leukemia (CLL) in Ukraine. PATIENTS AND METHODS: Immunoglobulin variable heavy chain (IGHV) gene repertoire was studied in 189 CLL patients using reverse transcribed polymerase chain reaction and direct sequence of amplified products. RESULTS: IGHV3-21 gene expression was found in 11 cases (5.8%), and its frequency was intermediate between Scandinavian (11.7%) and Mediterranean CLL (2.9%) cohorts. The most of cases (9 of 11) belonged to subset with heterogeneous HCDR3 (heteroHCDR3 subset), and only 2 cases--to subset with classical short ARDANGMDV motif (homHCDR3 subset). Six IGHV3-21 cases were mutated and 5 cases were unmutated. All unmutated cases (all were from heteroHCDR3 subset) had similarity of their HCDR3s with previously published sequences. The differences in overall (OS), progression-free (PFS) and treatment-free survival (TFS) for IGHV3-21 positive patients in comparison with CLL patients expressing the other IGHV genes were statistically insignificant. These survival parameters were comparable also for CLL patients with mutated IGHV3-21 gene usage and expression the others mutated IGHV genes. But remarkable feature of IGHV3-21 expressing patients was high incidence of solid tumors. They have developed in 4 IGHV3-21 positive cases (36.4%) and in 10 cases with expression of the others IGHV genes (5.6%, p=0.0002). Furthermore, in small group of 6 patients with mutated IGHV3-21 gene expression, 3 patients had solid tumors and one underwent Richter transformation. Unmutated IGHV3-21 gene expressed patients had worse OS and PFS in comparison with CLL patients that expressed the others unmutated IGHV genes. CONCLUSION: Presented data are in agreement with the opinion about negative prognostic significance of IGHV3-21 gene expression regardless its mutation status. IGHV3-21 expression was associated with development of secondary solid tumors. Revealed high level of homology in heteroHDR3s subset might suggest about possible antigenic influence also, in addition to homHCDR3 subset that was proposed earlier.


Assuntos
Expressão Gênica , Genes de Cadeia Pesada de Imunoglobulina , Leucemia Linfocítica Crônica de Células B/genética , Segunda Neoplasia Primária/genética , Adulto , Idoso , Sequência de Aminoácidos , Feminino , Citometria de Fluxo , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Humanos , Região Variável de Imunoglobulina/genética , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Ucrânia
8.
Vestn Oftalmol ; 121(4): 5-10, 2005.
Artigo em Russo | MEDLINE | ID: mdl-16223034

RESUMO

The paper presents data on the diagnostic use of three-dimensional (3-D) ultrasound visualization, analyzes earlier existing and new ultrasound diagnostic technologies, and shows it expedient to apply them in ophthalmologic practice. A hundred and forty-six healthy individuals and 52 patients (60 eyes) with different diseases of the eye and orbital cavity (chorioidal melanoma, facial angiomatosis, retinal detachment, vitreoretinal changes, etc.) were examined. The results of the studies and the analysis of the data available in the literature on this problem allow the authors to state that 3-D ultrasound diagnostic technologies can detect occult masses undetectable during conventional visual and ultrasound studies and define the topography of the dislocation of structurally complicated changes in the tunics of the eyeball.


Assuntos
Oftalmopatias/diagnóstico por imagem , Olho/diagnóstico por imagem , Imageamento Tridimensional , Órbita/diagnóstico por imagem , Diagnóstico Diferencial , Neoplasias Oculares/diagnóstico por imagem , Neoplasias Palpebrais/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Software , Ultrassonografia
9.
Parazitologiia ; 36(1): 26-32, 2002.
Artigo em Russo | MEDLINE | ID: mdl-11962199

RESUMO

Based on epizootological and epidemiological investigations in the Vologda province since 1958 till 2000, the combined territorial and temporal manifestations of natural foci of diseases was revealed. A natural focus occupies a complex of biotopes, and in different time the focus is activated in different areas, such as a river plain, marsh, meadow-field, and forest. Most commonly an activation of the natural focus appears in a border zone of three biotopes, namely, a forest, meadow-field, and river plain. A dependence of activation of various natural foci upon local climate conditions and fluctuations of micromammalian host number are considered.


Assuntos
Doenças Transmissíveis/epidemiologia , Ecologia , Animais , Clima , Fatores de Confusão Epidemiológicos , Encefalite Transmitida por Carrapatos/epidemiologia , Febre Hemorrágica com Síndrome Renal/epidemiologia , Humanos , Leptospirose/epidemiologia , Doença de Lyme/epidemiologia , Roedores , Federação Russa/epidemiologia , Estações do Ano , Temperatura , Fatores de Tempo , Tularemia/epidemiologia
10.
Neurotoxicology ; 19(4-5): 623-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9745921

RESUMO

Acetylcholinesterase (AChE) and neuropathy target esterase (neurotoxic esterase, NTE) are two major target enzymes for organophosphorus (OP) esters. The relative potency of an OP ester to react with AChE or with NTE in vitro correlates with its relative potency in vivo to cause acute toxicity (death) or organopohosphate-induced delayed neurotoxicity (OPIDN). On this basis extrapolation from in vitro to in vivo data now seems justifiable to predict risk of OPIDN. The kinetics of NTE and AChE inhibition by experimental pesticides of the general formula (RO)2P(O)ON=CClCH2Cl, where R = methyl, ethyl, isopropyl, propyl, isobutyl, butyl, pentyl, has been studied. Compounds with short R (methyl, ethyl) were shown to be far more potent inhibitors of AChE than NTE. Both anti-NTE activity, selectivity for NTE and, correspondingly, the propensity of compounds to cause OPIDN rise with increasing their hydrophobicity. A high value of ki(NTE)/ki(AChE) for R = pentyl suggests that this compound would have the potential to cause OPIDN at doses lower than the LD50. A quantitative structure-activity relationships (QSAR) analysis indicated that NTE and AChE have different structural and electronic requirements for their respective OP inhibitors.


Assuntos
Acetilcolinesterase/metabolismo , Alcanos/toxicidade , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Inibidores da Colinesterase/toxicidade , Inibidores Enzimáticos/toxicidade , Compostos Organofosforados/toxicidade , Algoritmos , Animais , Encéfalo/enzimologia , Galinhas , Isoflurofato/análogos & derivados , Isoflurofato/toxicidade , Cinética , Relação Estrutura-Atividade
11.
Zh Evol Biokhim Fiziol ; 31(4): 396-403, 1995.
Artigo em Russo | MEDLINE | ID: mdl-8779279

RESUMO

In order to validate a rodent biochemical model of delayed neurotoxicity of organophosphates (OP) inhibition of rat and hen brain neurotoxic esterase (NTE) by some dichlorovinyl phosphates and phosphonates was studied in vitro and in vivo. It was shown that compounds investigated exhibited the similar inhibitory potency to NTE from both species in vitro, in addition rat and hen NTE showed the same sensitivity to variation of the structure of OP inhibitors. A good correlation was found between pI50 estimated with enzymes from rat and hen trains: r2 = 0.951, n = 18, p < or = 0.05. NTE activities were also measured in rat and hen brains after acute administration of various dosages of potent axonopathic compound dipropyldichlorovinyl phosphate. The results obtained indicate that difference in species susceptibility to neurotoxic action of OP, in particular the absence of ataxia in rats, is not caused by difference in target enzyme sensitivity to axonopathic organophosphates.


Assuntos
Encéfalo/efeitos dos fármacos , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Organofosfatos/toxicidade , Compostos Organofosforados/toxicidade , Acetilcolinesterase/efeitos dos fármacos , Animais , Atropina/administração & dosagem , Encéfalo/enzimologia , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Hidrolases de Éster Carboxílico/isolamento & purificação , Galinhas , Inibidores da Colinesterase/toxicidade , Diclorvós/análogos & derivados , Diclorvós/toxicidade , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Masculino , Ratos , Especificidade da Espécie
13.
Vestn Oftalmol ; 106(6): 5-10, 1990.
Artigo em Russo | MEDLINE | ID: mdl-2075661

RESUMO

The results of 48 surgeries (refraction epikeratoplasty) for aphakia, high ametropia, and keratoconus evidence the efficacy of such operation in the afore-said conditions. Further studies are necessary to elucidate the pathogenesis of complications, improve the technique of surgery and technology of the transplant preparation in order to make it more safe and improve its functional results.


Assuntos
Transplante de Córnea/métodos , Ceratocone/cirurgia , Procedimentos Cirúrgicos Refrativos , Afacia Pós-Catarata/cirurgia , Estudos de Avaliação como Assunto , Humanos , Complicações Pós-Operatórias , Refração Ocular
15.
Vestn Oftalmol ; 105(3): 19-24, 1989.
Artigo em Russo | MEDLINE | ID: mdl-2665289

RESUMO

The results of experimental and clinical trials of a new type of transplantation of the cornea, stromaplasty, have shown the possibility of a blunt detachment from Descemet's membrane and removal of the deep lamellae of recipient's stroma, followed by replacement of the defect with a through allotransplant. Further studies are necessary to validate this first successful surgery and to objectively assess the prospects of such surgery.


Assuntos
Transplante de Córnea , Adulto , Doenças da Córnea/cirurgia , Lâmina Limitante Posterior/cirurgia , Seguimentos , Humanos , Masculino , Métodos , Fatores de Tempo , Acuidade Visual
16.
Vestn Oftalmol ; 105(2): 21-4, 1989.
Artigo em Russo | MEDLINE | ID: mdl-2728159

RESUMO

The results of keratometry of 13 allotransplants have confirmed the rightfulness of the employed methods for calculation of the parameters of biolenses for epikeratophakia. For clinical application the initial intumescence should be taken into consideration, as well as the donor tissue thickening during its freezing for working on a lathe.


Assuntos
Bioprótese , Lentes Intraoculares , Ciência de Laboratório Médico , Humanos , Matemática , Refração Ocular
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