Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
J Phys Chem B ; 123(6): 1324-1331, 2019 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-30657324

RESUMEN

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.
Artículo en Ruso | MEDLINE | ID: mdl-23035529

RESUMEN

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.


Asunto(s)
Apoptosis/efectos de la radiación , Roturas del ADN de Cadena Simple/efectos de la radiación , ADN/efectos de la radiación , Caspasa 3/metabolismo , Células Cultivadas , Citocromos c/metabolismo , Humanos , Linfocitos/efectos de la radiación , Redes y Vías Metabólicas/efectos de la radiación , Proteína p53 Supresora de Tumor/metabolismo , Rayos Ultravioleta , Receptor fas/metabolismo
3.
Radiats Biol Radioecol ; 51(4): 425-43, 2011.
Artículo en Ruso | MEDLINE | ID: mdl-21950100

RESUMEN

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.


Asunto(s)
Apoptosis/efectos de la radiación , Linfocitos/efectos de la radiación , Especies Reactivas de Oxígeno/metabolismo , Rayos Ultravioleta , Apoptosis/genética , Calcio/análisis , Caspasa 3/efectos de la radiación , Células Cultivadas , Ensayo Cometa/métodos , Fragmentación del ADN/efectos de la radiación , Expresión Génica , Humanos , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/efectos de la radiación , Receptor fas/metabolismo , Receptor fas/efectos de la radiación
4.
Tsitologiia ; 53(1): 61-7, 2011.
Artículo en Ruso | MEDLINE | ID: mdl-21473121

RESUMEN

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.


Asunto(s)
Roturas del ADN de Cadena Simple/efectos de los fármacos , Roturas del ADN de Cadena Simple/efectos de la radiación , Linfocitos/efectos de los fármacos , Linfocitos/efectos de la radiación , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Células Cultivadas , ADN/análisis , ADN/química , Fragmentación del ADN/efectos de los fármacos , Fragmentación del ADN/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Electroforesis en Gel de Agar , Humanos , Peróxido de Hidrógeno/farmacología , Radical Hidroxilo/metabolismo , Recuento de Linfocitos , Linfocitos/química , Linfocitos/citología , Oxígeno Singlete/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Rayos Ultravioleta
5.
Urologiia ; (3): 21-4, 2006.
Artículo en Ruso | MEDLINE | ID: mdl-16889084

RESUMEN

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.


Asunto(s)
Antígenos de Superficie/sangre , Biomarcadores de Tumor/sangre , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/diagnóstico , Diagnóstico Diferencial , Humanos , Masculino , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/patología , Hiperplasia Prostática/terapia , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/terapia , alfa 1-Antiquimotripsina/sangre
8.
Artículo en Ruso | MEDLINE | ID: mdl-11253387

RESUMEN

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.


Asunto(s)
Movimientos Sacádicos , Atención , Electroencefalografía , Humanos , Estimulación Luminosa , Tiempo de Reacción , Campos Visuales
9.
Eksp Klin Farmakol ; 63(2): 51-3, 2000.
Artículo en Ruso | MEDLINE | ID: mdl-10834095

RESUMEN

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.


Asunto(s)
Antineoplásicos Hormonales/farmacocinética , Tamoxifeno/farmacocinética , Útero/metabolismo , Animales , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Interacciones Farmacológicas , Femenino , Ligandos , Ratas , Receptores de Estradiol/efectos de los fármacos , Receptores de Estradiol/metabolismo , Estadísticas no Paramétricas , Tritio , Útero/efectos de los fármacos
10.
Eksp Klin Farmakol ; 62(5): 25-7, 1999.
Artículo en Ruso | MEDLINE | ID: mdl-10572747

RESUMEN

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.


Asunto(s)
Miometrio/efectos de los fármacos , Progesterona/análogos & derivados , Progestinas/farmacología , Contracción Uterina/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Femenino , Miometrio/fisiología , Embarazo , Ratas , Receptores de Progesterona/efectos de los fármacos , Receptores de Progesterona/fisiología , Estereoisomerismo , Relación Estructura-Actividad
15.
Eksp Klin Farmakol ; 57(6): 20-2, 1994.
Artículo en Ruso | MEDLINE | ID: mdl-7756949

RESUMEN

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.


Asunto(s)
Analgésicos/farmacología , Encefalinas/farmacología , Analgésicos/administración & dosificación , Animales , Gatos , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Encefalinas/administración & dosificación , Ratones , Dolor/tratamiento farmacológico , Ratas , Factores de Tiempo
16.
Biull Eksp Biol Med ; 112(10): 393-5, 1991 Oct.
Artículo en Ruso | MEDLINE | ID: mdl-1804354

RESUMEN

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.


Asunto(s)
Anabolizantes/farmacología , División Celular/efectos de los fármacos , Timo/efectos de los fármacos , Animales , ADN/metabolismo , Dexametasona/farmacología , Ecdisterona/farmacología , Metandrostenolona/farmacología , Ratones , Ratones Endogámicos C57BL , Tamaño de los Órganos , Testosterona/farmacología , Timidina/metabolismo , Timo/citología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...