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1.
J Phys Chem B ; 123(6): 1324-1331, 2019 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-30657324

RESUMO

Thermal and photoinduced processes accompanying complexation of photochromic spiropyrans (SPP) with Zn ions in acetone solution were characterized by means of UV-vis and X-ray absorption spectroscopies in operando regime. SPP ligands are usually transparent at λ > 350 nm, but after mixing with Zn ions, they produce a stable colored (ε = 32 000-38 000 M-1 cm-1) complex with maximum absorption at 525 nm, which makes them a powerful tool for monitoring metal-ion concentration in solution. The complex revealed fluorescence and photochromic behavior under static irradiation with visible light with constant photoreaction quantum yield across its characteristic absorption band. Zn K-edge X-ray absorption spectra show prominent changes in Zn local atomic structure between free Zn ions and Zn complex. The pump-flow-probe scheme was adapted to measure operando changes in Zn coordination upon light irradiation. Within experimental time resolution, we have determined that 20 µs after light irradiation, Zn ion is released out of the complex. This is the first example of the direct spectroscopic probe of the Zn photorelease from the spiropyran complex.

2.
Biofizika ; 57(4): 631-40, 2012.
Artigo em Russo | MEDLINE | ID: mdl-23035529

RESUMO

The level of DNA damage and cytochrome c content in human lymphocytes in the dynamics of apoptosis induced by UV-light (240-390 nm) at doses of 151, 1510 and 3020 J/m2 is studied. DNA fragmentation is revealed in 20 h after UV-irradiation of lymphocytes at doses mentioned above. It is shown that DNA damages (single strand breaks) appear immediately after UV-irradiation of lymphocytes at doses of 1510 and 3020 J/m2 (comets of C1 type) and reach their maximum 6 h after cell modification (comets of C2 and C3 types). It is concluded that p53-dependent and receptor caspase pathways are involved in apoptosis development in the human lymphocytes, modified after UV-irradiation.


Assuntos
Apoptose/efeitos da radiação , Quebras de DNA de Cadeia Simples/efeitos da radiação , DNA/efeitos da radiação , Caspase 3/metabolismo , Células Cultivadas , Citocromos c/metabolismo , Humanos , Linfócitos/efeitos da radiação , Redes e Vias Metabólicas/efeitos da radiação , Proteína Supressora de Tumor p53/metabolismo , Raios Ultravioleta , Receptor fas/metabolismo
3.
Radiats Biol Radioecol ; 51(4): 425-43, 2011.
Artigo em Russo | MEDLINE | ID: mdl-21950100

RESUMO

Changes of DNA structural condition, the level of membrane Fas-receptor expression, caspase-3 functional activity, concentrations of Ca2+, p53 and cytochrome c proteins of human lymphocytes in dynamics of apoptosis development induced by UV-light (240-390 nm) at doses 151, 1510, 3020 J/m2 and reactive oxygen species (superoxide anion-radical, hydroxyl radicals, hydrogen peroxide, singlet oxygen) have been studied. UV-light and reactive oxygen species have been established to induce fragmentation of lymphocyte DNA after 20 h incubation of the modified cells. It has been shown, that the increase in the expression level of membrane death Fas-receptors is observed during 1-5 h after exposure oflymphocytes to UV-light and ROS compared with intact cells. Also revealed is augmentation of lymphocyte caspase-3 functional activity 4 h after generation of singlet oxygen, hydroxyl radical and hydrogen peroxide addition, as well as 8 and 24 and 6 and 8 h after UV-irradiation of the cells at doses 151 and 1510 J/m2, correspondingly. Using DNA-comet method made it possible to tape that DNA damages (single-strand breaks) appear 15-20 min after lymphocyte UV-irradiation at doses 1510 and 3020 J/m and addition of hydrogen peroxide in concentration 10(-6) mol/l (C1 type comet) and reach their maximum 6 h after modification of the cells (C2 and C3 type comets). It has been observed, that 6 h after exposure oflymphocytes to hydrogen peroxide and UV-light at doses 1510 and 3020 J/m2, the p53 level of investigated cells raises. It has also been shown that the higher level of calcium in lymphocyte cytosol in conditions of UV-light exposure (1510 J/m2) and exogenous generation of reactive oxygen species is caused by Ca2+ exit from intracellular depots as a result of activating the components of the phosphoinositide mechanism for transferring information into a cell. Ideas about correlation between alterations of the calcium level and initiation of programmed cellular destruction of human lymphocytes after exposure to UV-irradiation and ROS is proposed. The authors come to the conclusion about the leading role of receptor-mediated (Fas-dependent) caspase- and p53-dependent ways of realizing apoptosis oflymphocytes induced by UV-light at doses 151 and 1510 J/m2 and active oxygen metabolites. The pattern of the possible intracellular events leading to apoptotic destruction of lymphocytes after their UV-irradiation is offered.


Assuntos
Apoptose/efeitos da radiação , Linfócitos/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Raios Ultravioleta , Apoptose/genética , Cálcio/análise , Caspase 3/efeitos da radiação , Células Cultivadas , Ensaio Cometa/métodos , Fragmentação do DNA/efeitos da radiação , Expressão Gênica , Humanos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/efeitos da radiação , Receptor fas/metabolismo , Receptor fas/efeitos da radiação
4.
Tsitologiia ; 53(1): 61-7, 2011.
Artigo em Russo | MEDLINE | ID: mdl-21473121

RESUMO

It is established that UV-light (240-390 nm) in doses of 151, 1510 and 3020 J/m2 and reactive oxygen species and singlet oxygen induce DNA fragmentation lymphocytes cells of the human 20 h after influence. Using a method of DNA-comets it is revealed that DNA damages (single strand breaks) are found out right after UV-irradiations of lymphocytes in doses of 1510 and 3020 J/m2 and additions hydrogen peroxide in concentration of 10-6 mol/l (a comet of type C1) and reach a maximum through 6 h after influence on of cells UV-light and ROS (comets of types C2 and C3). Assumption about the leading part of a p53-dependent way in realization apoptosis human lymphocytes in the conditions of influence of UV-light and reactive oxygen species is put forward.


Assuntos
Quebras de DNA de Cadeia Simples/efeitos dos fármacos , Quebras de DNA de Cadeia Simples/efeitos da radiação , Linfócitos/efeitos dos fármacos , Linfócitos/efeitos da radiação , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Células Cultivadas , DNA/análise , DNA/química , Fragmentação do DNA/efeitos dos fármacos , Fragmentação do DNA/efeitos da radiação , Relação Dose-Resposta à Radiação , Eletroforese em Gel de Ágar , Humanos , Peróxido de Hidrogênio/farmacologia , Radical Hidroxila/metabolismo , Contagem de Linfócitos , Linfócitos/química , Linfócitos/citologia , Oxigênio Singlete/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Raios Ultravioleta
5.
Urologiia ; (3): 21-4, 2006.
Artigo em Russo | MEDLINE | ID: mdl-16889084

RESUMO

The aim of the study was to compare diagnostic significance of free PSA (fPSA)/total PSA (tPSA) versus PSA complex with alpha1-antichymotrypsin (cPSA) in tPSA level within 4-10 ng/ml in differential diagnosis of prostatic cancer (PC). A complete urological examination (digital rectal test, transrectal ultrasound investigation, serum assay for fPSA and tPSA, multifocal transperineal prostatic biopsy) was made in 108 patients with tPSA blood level 4-10 ng/ ml. Prostatic adenoma (PA) was histologically verified in 61 of 108 patients, fPSA/tPSA was normal. In the other 39 of 108 patients fPSA/tPSA was under 15% while cPSA was in the range 3.8-9.6 ng/ml. A course of etiotropic therapy of chronic prostatic inflammation produced no significant changes in fPSA/tPSA and cPSA in 28 out of 39 patients. Histologically, these 28 patients had PC. In the rest 11 of 39 patients chronic prostatitis treatment fPSA/tPSA significantly rose to 18.2%, on the average. CPSA decreased to 2.4 ng/ml. These 11 patients were found histologically to have PA and signs of chronic inflammation. In 8 of 108 patients fPSA/tPSA was not indicative of PC being 18,2% on the average while cPSA indicated the presence of PC and was 4.2 ng.ml, on the average. PC was verified histologically in these 8 patients. Thus, cPSA in PC suspects is more informative than fPSA/tPSA in PC diagnosis. CPSA in the serum depends on prostatic inflammation making difficult differential diagnosis of PC in interpretation of tPSA, fPSA/tPSA and cPSA. Therefore, estimation of PSA variants and molecular forms in PC suspects and prostatic inflammation should be made after etiotropic therapy.


Assuntos
Antígenos de Superfície/sangue , Biomarcadores Tumorais/sangue , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico , Diagnóstico Diferencial , Humanos , Masculino , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/patologia , Hiperplasia Prostática/terapia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , alfa 1-Antiquimotripsina/sangue
8.
Artigo em Russo | MEDLINE | ID: mdl-11253387

RESUMO

The latent periods of saccadic eye movements in response to peripheral visual stimuli were measured in 8 right-handed healthy subjects using Posner's paradigm "COST-BENEFIT". In 6 subjects, the saccade latency in response to visual target presented in expected location in valid condition was shorter than that in neutral condition ("benefit"). Increase in saccade latency in response to the visual target presented in unexpected location in valid condition versus neutral condition took place only in 4 subjects ("cost"). A decrease in left-directed saccade latency in response to expected target presented in the left hemifield and increase in saccade latency in response to unexpected left target in comparison with analogous right-directed saccades were observed in valid condition. This phenomenon can be explained by the dominance of the right hemisphere in the processes of spatial orientation and "disengage" of attention.


Assuntos
Movimentos Sacádicos , Atenção , Eletroencefalografia , Humanos , Estimulação Luminosa , Tempo de Reação , Campos Visuais
9.
Eksp Klin Farmakol ; 63(2): 51-3, 2000.
Artigo em Russo | MEDLINE | ID: mdl-10834095

RESUMO

The effect of phencarol, ranitidine, propranolol, atropine, and diethylstilbestrol (known as modulators of the tamoxifen-binding sites in plasma membranes) on the 3H-tamoxifen binding to the plasma membrane fraction of white rat uterine cells was studied by determining the amounts of estradiol and H1- and H2-receptors. The interaction of tamoxifen with various receptors of uterine cells may be significant for evaluation of the tumor activity of this compound.


Assuntos
Antineoplásicos Hormonais/farmacocinética , Tamoxifeno/farmacocinética , Útero/metabolismo , Animais , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Interações Medicamentosas , Feminino , Ligantes , Ratos , Receptores de Estradiol/efeitos dos fármacos , Receptores de Estradiol/metabolismo , Estatísticas não Paramétricas , Trítio , Útero/efeitos dos fármacos
10.
Eksp Klin Farmakol ; 62(5): 25-7, 1999.
Artigo em Russo | MEDLINE | ID: mdl-10572747

RESUMO

The authors studied the effect of synthetic gestagens on spontaneous contractility of the myometrium in pregnant rats. The direction of the effect of progesterone and its analogs on the contractility is determined by stereochemistry of the linkage of rings A and B of the steroid molecule. Compounds possessing translinkage (5 beta-steroids) increase the amplitude of myometrium contraction, whereas their analogs with cms-coupling of rings A and B (5 alpha-steroids), and 4,5-unsaturated steroids reduce it.


Assuntos
Miométrio/efeitos dos fármacos , Progesterona/análogos & derivados , Progestinas/farmacologia , Contração Uterina/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Feminino , Miométrio/fisiologia , Gravidez , Ratos , Receptores de Progesterona/efeitos dos fármacos , Receptores de Progesterona/fisiologia , Estereoisomerismo , Relação Estrutura-Atividade
15.
Eksp Klin Farmakol ; 57(6): 20-2, 1994.
Artigo em Russo | MEDLINE | ID: mdl-7756949

RESUMO

The enkephalin analogue peptide IKB-901 containing epsilon-ACA and cysteine with the modified S-end shows an analgetic activity in rats (1 micron, intrathecally and 5 mg/kg intravenously) and in cats (0.35 and 0.7 mg/kg intravenously). Naloxone (0.1 mg/kg) prevents the analgetic effect of peptide. The coadministration of the peptide and the enkephalinase inhibitor D-phenylalanine (0.35 and 10 mg/kg, respectively) enhances analgesia and displays an antihypertensive effect in nociceptive stimulation.


Assuntos
Analgésicos/farmacologia , Encefalinas/farmacologia , Analgésicos/administração & dosagem , Animais , Gatos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Encefalinas/administração & dosagem , Camundongos , Dor/tratamento farmacológico , Ratos , Fatores de Tempo
16.
Biull Eksp Biol Med ; 112(10): 393-5, 1991 Oct.
Artigo em Russo | MEDLINE | ID: mdl-1804354

RESUMO

Testosterone, methandrostenolone during ten-day injections to mice 50 mg/kg decrease mass, quality of DNA and 3H thymidine in Thymus. In vitro these drugs loss 3H-thymidine incorporation at 10(-5) M. Ecdysthene do not influence proliferative activity of thymocytes in vitro and thymolytyc effect in vivo. The present results indicate, that proliferative process may have a functional significance in thymolytycal effects of anabolic steroids.


Assuntos
Anabolizantes/farmacologia , Divisão Celular/efeitos dos fármacos , Timo/efeitos dos fármacos , Animais , DNA/metabolismo , Dexametasona/farmacologia , Ecdisterona/farmacologia , Metandrostenolona/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Tamanho do Órgão , Testosterona/farmacologia , Timidina/metabolismo , Timo/citologia
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