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1.
BMC Plant Biol ; 20(1): 467, 2020 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-33045997

RESUMEN

BACKGROUND: This study describes a promising method for understanding how halophytes adapt to extreme saline conditions and to identify populations with greater resistance. Image and colour analyses have the ability to obtain many image parameters and to discriminate between different aspects in plants, which makes them a suitable tool in combination with genetic analysis to study the plants salt tolerance. To the best of our knowledge, there are no publications about the monitoring of halophytic plants by non-destructive methods for identifying the differences between plants that belong to different maternal salinity environments. The aim is to evaluate the ability of image analysis as a non-destructive method and principal component analysis (PCA) to identify the multiple responses of two S. europaea populations, and to determine which population is most affected by different salinity treatments as a preliminary model of selection. RESULTS: Image analysis was beneficial for detecting the phenotypic variability of two S. europaea populations by morphometric and colour parameters, fractal dimension (FD), projected area (A), shoot height (H), number of branches (B), shoot diameter (S) and colour change (ΔE). S was found to strongly positively correlate with both proline content and ΔE, and negatively with chlorophyll content. These results suggest that proline and ΔE are strongly linked to plant succulence, while chlorophyll decreases with increased succulence. The negative correlation between FD and hydrogen peroxide (HP) suggests that when the plant is under salt stress, HP content increases in plants causing a reduction in plant complexity and foliage growth. The PCA results indicate that the greater the stress, the more marked the differences. At 400 mM a shorter distance between the factorial scores was observed. Genetic variability analysis provided evidence of the differences between these populations. CONCLUSIONS: Our non-destructive method is beneficial for evaluating the halophyte development under salt stress. FD, S and ΔE were relevant indicators of plant architecture. PCA provided evidence that anthropogenic saline plants were more tolerant to saline stress. Furthermore, random amplified polymorphic DNA analysis provided a quick method for determining genetic variation patterns between the two populations and provided evidence of genetic differences between them.


Asunto(s)
Chenopodiaceae/crecimiento & desarrollo , Chenopodiaceae/genética , Salinidad , Tolerancia a la Sal/genética , Tolerancia a la Sal/fisiología , Plantas Tolerantes a la Sal/genética , Plantas Tolerantes a la Sal/fisiología , Fractales , Variación Genética , Genotipo , Polonia
2.
Radiat Environ Biophys ; 59(3): 357-387, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32372284

RESUMEN

This work presents an overview of the applications of retrospective dosimetry techniques in case of incorporation of radionuclides. The fact that internal exposures are characterized by a spatially inhomogeneous irradiation of the body, which is potentially prolonged over large periods and variable over time, is particularly problematic for biological and electron paramagnetic resonance (EPR) dosimetry methods when compared with external exposures. The paper gives initially specific information about internal dosimetry methods, the most common cytogenetic techniques used in biological dosimetry and EPR dosimetry applied to tooth enamel. Based on real-case scenarios, dose estimates obtained from bioassay data as well as with biological and/or EPR dosimetry are compared and critically discussed. In most of the scenarios presented, concomitant external exposures were responsible for the greater portion of the received dose. As no assay is available which can discriminate between radiation of different types and different LETs on the basis of the type of damage induced, it is not possible to infer from these studies specific conclusions valid for incorporated radionuclides alone. The biological dosimetry assays and EPR techniques proved to be most applicable in cases when the radionuclides are almost homogeneously distributed in the body. No compelling evidence was obtained in other cases of extremely inhomogeneous distribution. Retrospective dosimetry needs to be optimized and further developed in order to be able to deal with real exposure cases, where a mixture of both external and internal exposures will be encountered most of the times.


Asunto(s)
Radiación Ionizante , Radiometría/métodos , Animales , Espectroscopía de Resonancia por Spin del Electrón , Humanos , Radioisótopos/farmacocinética
3.
Mol Psychiatry ; 20(10): 1179-87, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26055427

RESUMEN

In a positron-emission tomography (PET) study with the ß-amyloid (Aß) tracer [(18)F]-florbetaben, we previously showed that Aß deposition in transgenic mice expressing Swedish mutant APP (APP-Swe) mice can be tracked in vivo. γ-Secretase modulators (GSMs) are promising therapeutic agents by reducing generation of the aggregation prone Aß42 species without blocking general γ-secretase activity. We now aimed to investigate the effects of a novel GSM [8-(4-Fluoro-phenyl)-[1,2,4]triazolo[1,5-a]pyridin-2-yl]-[1-(3-methyl-[1,2,4]thiadiazol-5-yl)-piperidin-4-yl]-amine (RO5506284) displaying high potency in vitro and in vivo on amyloid plaque burden and used longitudinal Aß-microPET to trace individual animals. Female transgenic (TG) APP-Swe mice aged 12 months (m) were assigned to vehicle (TG-VEH, n=12) and treatment groups (TG-GSM, n=12), which received daily RO5506284 (30 mg kg(-1)) treatment for 6 months. A total of 131 Aß-PET recordings were acquired at baseline (12 months), follow-up 1 (16 months) and follow-up 2 (18 months, termination scan), whereupon histological and biochemical analyses of Aß were performed. We analyzed the PET data as VOI-based cortical standard-uptake-value ratios (SUVR), using cerebellum as reference region. Individual plaque load assessed by PET remained nearly constant in the TG-GSM group during 6 months of RO5506284 treatment, whereas it increased progressively in the TG-VEH group. Baseline SUVR in TG-GSM mice correlated with Δ%-SUVR, indicating individual response prediction. Insoluble Aß42 was reduced by 56% in the TG-GSM versus the TG-VEH group relative to the individual baseline plaque load estimates. Furthermore, plaque size histograms showed differing distribution between groups of TG mice, with fewer small plaques in TG-GSM animals. Taken together, in the first Aß-PET study monitoring prolonged treatment with a potent GSM in an AD mouse model, we found clear attenuation of de novo amyloidogenesis. Moreover, longitudinal PET allows non-invasive assessment of individual plaque-load kinetics, thereby accommodating inter-animal variations.


Asunto(s)
Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Placa Amiloide/tratamiento farmacológico , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/patología , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Compuestos de Anilina/síntesis química , Compuestos de Anilina/farmacología , Animales , Estudios de Casos y Controles , Angiopatía Amiloide Cerebral/terapia , Modelos Animales de Enfermedad , Femenino , Estudios Longitudinales , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Placa Amiloide/diagnóstico por imagen , Placa Amiloide/enzimología , Placa Amiloide/metabolismo , Tomografía de Emisión de Positrones/métodos , Estilbenos/síntesis química , Estilbenos/farmacología
4.
J Intellect Disabil Res ; 60(6): 564-70, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27028200

RESUMEN

BACKGROUND: Little is known about depression among women with Rett syndrome (RTT) despite recent advances in knowledge about RTT. In this study, we aimed to establish the prevalence of depression among women with RTT as identified by a screening telephone interview and to explore the clinical factors associated with this. METHODS: The study employed the cross-sectional analysis of data from telephone interviews with carers of 56 women with RTT, using validated questionnaires for assessing mental health problems, challenging behaviour and RTT severity. RESULTS: Scores on the mental health assessment reached the affective/neurotic threshold in eight cases (14.3%). No significant differences were found between those reaching the threshold and those who did not in terms of severity of RTT phenotype, health problems or social circumstances. There was a significant association between screening identified depression and higher lethargy and social withdrawal. CONCLUSIONS: Screening identified depression was found among a sizeable minority of women with RTT. Further investigation is needed to establish a clinically validated prevalence of depression among this group and to identify behavioural features that would lead to prompt psychiatric assessment.


Asunto(s)
Trastorno Depresivo/fisiopatología , Síndrome de Rett/fisiopatología , Adulto , Comorbilidad , Estudios Transversales , Trastorno Depresivo/epidemiología , Femenino , Humanos , Persona de Mediana Edad , Prevalencia , Síndrome de Rett/epidemiología , Adulto Joven
5.
Analyst ; 140(7): 2330-5, 2015 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-25700000

RESUMEN

Intracellular redox potential is a highly regulated cellular characteristic and is critically involved in maintaining cellular health and function. The dysregulation of redox potential can result in the initiation and progression of numerous diseases. Redox potential is determined by the balance of oxidants and reductants in the cell and also by pH. For this reason a technique for quantitative measurement of intracellular redox potential and pH is highly desirable. In this paper we demonstrate how surface enhanced Raman scattering (SERS) nanosensors can be used for multiplexed measurement of both pH and redox potential in live single cells.


Asunto(s)
Espacio Intracelular/química , Espacio Intracelular/metabolismo , Nanotecnología , Espectrometría Raman , Línea Celular , Supervivencia Celular , Humanos , Concentración de Iones de Hidrógeno , Oxidación-Reducción
7.
J Environ Radioact ; 99(9): 1474-83, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18550231

RESUMEN

The ERICA Integrated Approach requires that a risk assessment screening dose rate is defined for the risk characterisation within Tiers 1 and 2. At Tier 3, no numerical screening dose rate is used, and the risk characterisation is driven by methods that can evaluate the possible effects of ionising radiation on reproduction, mortality and morbidity. Species sensitivity distribution has been used to derive the ERICA risk assessment predicted no-effect dose rate (PNEDR). The method used was based on the mathematical processing of data from FRED (FASSET radiation effects database merged with the EPIC database to form FREDERICA) and resulted in a PNEDR of 10 microGy/h. This rate was assumed to ascribe sufficient protection of all ecosystems from detrimental effects on structure and function under chronic exposure. The value was weighed against a number of points of comparison: (i) PNEDR values obtained by application of the safety factor method, (ii) background levels, (iii) dose rates triggering effects on radioactively contaminated sites and (iv) former guidelines from literature reviews. In Tier 3, the effects analysis must be driven by the problem formulation and is thus highly case specific. Instead of specific recommendations on numeric values, guidance on the sorts of methods that may be applied for refined effect analysis is provided and illustrated.


Asunto(s)
Ecosistema , Monitoreo de Radiación/métodos , Radiación Ionizante , Medición de Riesgo/métodos , Animales , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , Desarrollo de la Planta , Plantas/efectos de la radiación , Literatura de Revisión como Asunto
8.
Chem Biol Interact ; 258: 69-78, 2016 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-27545834

RESUMEN

This study evaluated the effect of electron beam irradiation on the cytotoxic activity of anthracycline antibiotics such as doxorubicin (DOX), epirubicin (EPI), and dunorubicin (DAU) in human acute lymphoblastic leukemia cell line CCRF-CEM and its multidrug-resistant variant CCRF-VCR1000 cell line characterized by the overexpression of ABCB1 gene. Drugs were irradiated at doses of 10 and 25 kGy. Data from EPR studies proved that the highest concentration of free radicals was found in DOX and that the number of stable free radicals is always greater after irradiation. In in vitro studies, a higher cytotoxic activity of irradiated DOX and EPI in multidrug-resistant CCRF-VCR1000 cells was observed. This tendency was maintained during the storage at 4 °C for 90 days. Changes in CCRF-CEM cells' viability were not dependent on the irradiation status and its dose and were only drug-concentration dependent in all measurement time points. It was proved that increased potency of 25 kGy e-beam irradiated drugs results from their enhanced proapoptotic activity. Apoptotic cell death observed in CCRF-VCR1000 cells treated with irradiated drugs was caspase-8, -9, and -3 dependent and related to the increased Bax/Bcl-2 ratio. No significant differences in the effects of irradiated and non-irradiated drugs on p53 and NFκB transcription factor level and their translocation to the nucleus were noted. Increased activity of the irradiated drugs was not dependent on ABCB1 level.


Asunto(s)
Apoptosis/efectos de los fármacos , Doxorrubicina/farmacología , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Múltiples Medicamentos/efectos de la radiación , Electrones , Epirrubicina/farmacología , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Apoptosis/efectos de la radiación , Western Blotting , Caspasas/metabolismo , Línea Celular Tumoral , Daunorrubicina/química , Daunorrubicina/farmacología , Doxorrubicina/química , Espectroscopía de Resonancia por Spin del Electrón , Epirrubicina/química , Radicales Libres/metabolismo , Humanos , FN-kappa B/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Proteína p53 Supresora de Tumor/metabolismo
9.
Chem Biol Interact ; 242: 1-12, 2015 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-26362502

RESUMEN

One of the main problems of present-day oncology is the ability of neoplastic cells to develop different mechanisms of resistance to chemotherapeutic agent. A natural compound oleanolic acid (OA) was found to be active against many types of neoplastic cells. This paper examines the influence of eight semisynthetic oleanolic acid derivatives on drug-sensitive human acute promyelocytic leukemia cell line HL-60 and its multidrug resistant subline ABCC1 overexpressing HL-60/AR. Viability inhibition, proapoptotic activity, as well as influence on the ABCC1 gene expression level, ability to inhibit the transport function of multidrug resistance associated protein 1 (ABCC1) and to alter its level by the tested compounds, were evaluated. The most potent compounds were DIOXOL (methyl 3,11-dioxoolean-12-en-28-oate) and HIMOXOL (methyl 3-hydroxyimino-11-oxoolean-12-en-28-oate). DIOXOL was most efficient in inducing apoptosis of HL-60 cells. It activated both intrinsic and extrinsic pathways of apoptotic cell death. Proapoptotic properties of DIOXOL were probably related to the significant decrease of p65 NFκB level and inhibition of its translocation to the nucleus. In turn, HIMOXOL was the most potent compound against resistant HL-60/AR cells. It inhibited ABCC1 transport function (short time response) and decreased the level of ABCC1 protein (long time response) as a result of reduction of ABCC1 expression.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Leucemia Promielocítica Aguda/tratamiento farmacológico , Ácido Oleanólico/análogos & derivados , Fragmentación del ADN/efectos de los fármacos , Resistencia a Múltiples Medicamentos , Células HL-60/efectos de los fármacos , Células HL-60/enzimología , Humanos , Leucemia Promielocítica Aguda/patología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Terapia Molecular Dirigida/métodos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/antagonistas & inhibidores , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Ácido Oleanólico/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Factor de Transcripción ReIA/metabolismo
10.
Radiat Prot Dosimetry ; 164(1-2): 42-5, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25205835

RESUMEN

Creating a sustainable network in biological and retrospective dosimetry that involves a large number of experienced laboratories throughout the European Union (EU) will significantly improve the accident and emergency response capabilities in case of a large-scale radiological emergency. A well-organised cooperative action involving EU laboratories will offer the best chance for fast and trustworthy dose assessments that are urgently needed in an emergency situation. To this end, the EC supports the establishment of a European network in biological dosimetry (RENEB). The RENEB project started in January 2012 involving cooperation of 23 organisations from 16 European countries. The purpose of RENEB is to increase the biodosimetry capacities in case of large-scale radiological emergency scenarios. The progress of the project since its inception is presented, comprising the consolidation process of the network with its operational platform, intercomparison exercises, training activities, proceedings in quality assurance and horizon scanning for new methods and partners. Additionally, the benefit of the network for the radiation research community as a whole is addressed.


Asunto(s)
Bioensayo/métodos , Planificación en Desastres/organización & administración , Traumatismos por Radiación/prevención & control , Monitoreo de Radiación/métodos , Protección Radiológica/métodos , Liberación de Radiactividad Peligrosa/prevención & control , Urgencias Médicas , Europa (Continente) , Humanos , Exposición a la Radiación/prevención & control , Administración de la Seguridad/organización & administración
11.
Acta Biochim Pol ; 44(2): 215-20, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9360710

RESUMEN

A new enzymatic activity, which catalyses formation in vitro of di-O-(indole-3-acetyl)-D-glucose from 1-O-(indole-3-acetyl)-beta-D-glucose has been found in extracts of Zea mays seedlings. The structure of di-O-(indole-3-acetyl)-D-glucose, not as yet described, has been assigned by GC-MS, 1H NMR and ammonolysis.


Asunto(s)
Glucósidos/metabolismo , Indoles/metabolismo , Proteínas de Plantas/aislamiento & purificación , Proteínas de Plantas/metabolismo , Zea mays/enzimología , Catálisis , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Polietilenglicoles
12.
Int J Radiat Biol ; 60(6): 899-906, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1682402

RESUMEN

It is shown that paraquat treatment (1 h, 1 x 10(-5) mol/l) increases the activity of superoxide dismutase (SOD) in L5178Y (LY) R and S cells by about three times. When combined with X-irradiation, 0.5 h of treatment preceding irradiation increased the SOD activity two-fold and the alpha/beta ratio three-fold, as estimated from the X-ray survival curves. LY-S cells were more sensitive than LY-R cells to treatment with paraquat alone. These results indicate that SOD may be a radioprotective enzyme in LY strains and that LY-S cells are particularly sensitive to superoxide radicals as a result of a relatively low SOD activity. This explains their sensitivity to paraquat, which generates O2-, and to X-rays. The low SOD level may also explain the higher initial DNA damage in X-irradiated LY-S than LY-R cells.


Asunto(s)
Paraquat/farmacología , Tolerancia a Radiación/efectos de los fármacos , Superóxido Dismutasa/efectos de los fármacos , Animales , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Relación Dosis-Respuesta a Droga , Relación Dosis-Respuesta en la Radiación , Cinética , Ratones , Paraquat/toxicidad , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa/efectos de la radiación , Células Tumorales Cultivadas , Ensayo de Tumor de Célula Madre
13.
Int J Radiat Biol ; 77(3): 269-80, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11258841

RESUMEN

PURPOSE: To examine the possible associations between radiation sensitivity to doses 2 Gy, and such features of lymphoid cell responses as apoptosis, expression of apoptosis regulatory proteins (Bcl-2 family) and cell cycle progression in relation to biological dosimetry. MATERIALS AND METHODS: The cell lines examined were: Epstein Barr virus transformed lymphoid ataxia-telangiectasia (AT) cell lines, GM00717C, homozygous, and GM00736A, heterozygous, for ATM; human pro-B lymphoblastic leukaemia, Reh; murine L5178Y lymphoma sublines, LY-R and LY-S. Assays performed following X-irradiation with doses from 0.1 to 2 Gy were: terminal deoxyribonucleotidyl transferase (TdT) assay to measure apoptotic fraction, DNA content analysis by flow cytometry to assess cell cycle distribution, trypan blue exclusion test to determine cell viability, cytochalasin block micronucleus assay to assess cytogenetic damage, and Western blotting to detect proteins from the Bcl-2 family. RESULTS: The cell lines in the study were of different but rather high radiation sensitivity, which was unrelated to their propensity to undergo apoptosis or micronucleus frequency. The expression of apoptotic regulatory proteins from the Bcl-2 family (constitutive and expressed 4 or 24 h after irradiation) was not related to radiation sensitivity. CONCLUSION: None of the simple predictive tests used in the study, alone or evaluated together was suitable for detection of radiation hypersensitivity although cells known to be hypersensitive (LY-S and GM00717C) were included in the analysis.


Asunto(s)
Linfocitos/efectos de la radiación , Tolerancia a Radiación , Animales , Apoptosis , Biomarcadores , Recuento de Células , Ciclo Celular/efectos de la radiación , Línea Celular , Supervivencia Celular/efectos de la radiación , ADN/análisis , ADN/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Citometría de Flujo , Humanos , Etiquetado Corte-Fin in Situ , Linfocitos/metabolismo , Linfocitos/patología , Ratones , Pruebas de Micronúcleos , Valor Predictivo de las Pruebas , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo
14.
Chem Biol Interact ; 74(3): 221-31, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2347002

RESUMEN

A number of polyamine (PA) derivatives of thiosemicarbazone of 1,3-dichloroacetone (TDA) have been prepared and their effect on growth in vivo of tumorigenic but not metastatic cell strain (LY-R) of mouse lymphoma L5178Y has been investigated. Polyamine derivatives of TDA (PDT) were injected i.p. every third day (4 times, 10 or 25 mg/kg per injection) into DBA/2 mice inoculated i.p. or s.c. with LY-R cells. It has been found that disubstituted putrescine (Put), spermidine (Spd) and spermine (Spm) derivatives TDA exhibit a prometastatic activity as indicated by the appearance of solid tumor foci in subcutaneous tissues, liver and spleen. This activity depends mainly on the structure of the PA fragment and the presence of TDA. An increase in lipid bound sialic acid content after treating LY-R cells in vitro and in vivo with a Spm derivative has been found. These findings suggest that disubstituted PA derivatives of TDA and LY-R cells may be a useful model for investigation of the final steps in formation of metastases by lymphoma cells.


Asunto(s)
Acetona/análogos & derivados , Leucemia L5178/patología , Leucemia Experimental/patología , Poliaminas , Ácidos Siálicos/metabolismo , Tiosemicarbazonas/administración & dosificación , Animales , Gangliósidos/aislamiento & purificación , Leucemia L5178/metabolismo , Masculino , Ratones , Ratones Endogámicos DBA , Metástasis de la Neoplasia , Relación Estructura-Actividad
15.
J Photochem Photobiol B ; 58(2-3): 170-4, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11233646

RESUMEN

Cells from the mouse lymphoma cell line L5178Y-R were exposed to blue light from phototherapy lamps in the presence of solutions of 160 microM bilirubin supplemented with serum albumin. HPLC analysis showed that the bilirubin solution was photooxidised as a function of increasing light dose. The cells were stained with trypan blue to score necrosis, and apoptosis was assayed by the terminal deoxynucleotide transferase assay (TdT) or by studying the nuclear structure in cells stained with propidium iodide. A rapidly developing apoptosis was observed after light doses killing 60-80% of the cells as judged from the trypan blue exclusion test. The fraction of apoptotic cells was smaller than the fraction of necrotic cells. Exposure of the cells to fractions of light at a high dose rate was compared to the effect of the same total dose at a lower dose rate given as a single fraction. No large differences were found, however, there was a tendency of a higher degree of necrosis as well as apoptosis in the cells receiving the light in fractions at a high dose rate.


Asunto(s)
Bilirrubina/farmacología , Linfoma/terapia , Fototerapia , Animales , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Linfoma/patología , Ratones , Fotobiología , Fármacos Fotosensibilizantes/farmacología , Células Tumorales Cultivadas
16.
Radiats Biol Radioecol ; 42(6): 595-9, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12530132

RESUMEN

The most commonly used indicators of ionizing radiation exposure are cytogenetic measures and survival parameters. All these methods have their advantages, disadvantages and uncertainties, such that better biological estimators of the absorbed dose, especially in the low dose range, are being sought. In this study we analyzed apoptosis and several proteins involved in the regulation of apoptosis as possible indicators of irradiation after relatively small doses (0.1-2 Gy) of X-rays. The studies were carried out in seven lymphoid cell lines: two mouse lymphoma L5178Y, the human pre-B cell leukemia Reh, and four human Epstein-Barr virus-transformed lymphoid cell lines (two apparently normal and two Ataxia-telangiectasia (AT)). We detected apoptosis with the in situ terminal deoxynucleotidyl transferase assay and flow cytometry, and measured the expression of several apoptotic-regulatory proteins (Bcl-2, Bax, Bclx, NF kappa B) with Western blotting. The cytokinesis-block micronucleus assay, comet assay as a measure of DNA damage, and trypan blue survival test were also done for comparison Although for the most of examined parameters of radiation sensitivity: i.e. micronucleus assay, trypan blue test and percentage of apoptosis--there were observed clear dose-effect relationships for all cell lines examined, we did not find agreement between values for these measured parameters. There are marked differences in both timing of apoptosis and percentage of apoptotic cells. Variation in the apoptotic fraction in the controls for different sets of experiments is not very pronounced. There is however considerable variation for the same parameters in irradiated cells, possibly due to their cell cycle status during irradiation, as the cultures were not synchronized. Overall, neither the numbers of apoptotic cells nor the expression of apoptosis-related proteins, nor DNA repair can serve as dose estimators or sensors for these lines, but still these parameters can give valuable supplementary information about radiation sensitivity.


Asunto(s)
Biomarcadores , Linfocitos/efectos de la radiación , Tolerancia a Radiación , Animales , Western Blotting , Línea Celular Transformada , Ensayo Cometa , Daño del ADN , Humanos , Linfocitos/metabolismo , Ratones , Pruebas de Micronúcleos , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Células Tumorales Cultivadas , Rayos X
17.
Wiad Parazytol ; 47 Suppl 1: 107-12, 2001.
Artículo en Polaco | MEDLINE | ID: mdl-16897960

RESUMEN

The effectiveness of neonatal screening for anti-Toxoplasma IgM or IgA and IgM specific antibodies followed by an intensive anti-parasitic therapy for a prevention of clinical and immunological reactivations of congenital infection was studied. Thirty-five congenitally infected infants were included into clinical and serological follow-up. The children were mostly asymptomatic at birth or they expressed some non-specific reversible clinical abnormalities in neonatal period. Clinically overt toxoplasmosis occurred in 10 patients, including one infant with a severe form; 2 children had co-existing CMV infections. During the follow-up period, no clinical relapses were reported. Asymptomatic immunological rebounds of IgG or of IgG and IgA specific antibodies were observed in 16 patients. Anti-parasitic treatment initiated soon after birth seems to be promising in a prevention of early clinical sequelae of congenital T. gondii infection.


Asunto(s)
Enfermedades del Sistema Nervioso Central/diagnóstico , Inmunoglobulina M/sangre , Tamizaje Neonatal/organización & administración , Complicaciones Parasitarias del Embarazo/diagnóstico , Complicaciones Parasitarias del Embarazo/prevención & control , Toxoplasmosis Congénita/diagnóstico , Toxoplasmosis Congénita/prevención & control , Animales , Anticuerpos Antiprotozoarios/sangre , Enfermedades del Sistema Nervioso Central/prevención & control , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Polonia/epidemiología , Embarazo , Evaluación de Programas y Proyectos de Salud , Toxoplasma , Resultado del Tratamiento
18.
Klin Oczna ; 94(10): 303-4, 1992 Oct.
Artículo en Polaco | MEDLINE | ID: mdl-1306542

RESUMEN

The authors present an analysis of the results of treatment of patients with injury of the central fragment of the face, who have been hospitalized in the 2nd Department of the Maxillofacial surgery in Silesian Academy of Medicine. In the period 1980-1987 there were 447 patients with an injury of the central fragment of the face. Among this group 60 (13.4 p.c.) patients showed disturbances of the visual system. The most frequent causes of the injury were: assault (61.5 p.c.), traffic accidents (20.1 p.c.), occupational injuries (8.8 p.c.). Deformation of the face was the most frequent pathology observed in the course of a control stomatological check-up (32.0 p.c.). The most important ocular pathology were the posttraumatic atrophy of the eye (3.3 p.c.) and optic atrophy. Palpebral scars (33 p.c.) and diplopia (7.6 p.c.) were the most frequent ocular signs.


Asunto(s)
Lesiones Oculares/cirugía , Traumatismos Faciales/cirugía , Oftalmopatías/etiología , Femenino , Humanos , Masculino , Complicaciones Posoperatorias/etiología , Resultado del Tratamiento
19.
Radiat Prot Dosimetry ; 151(4): 621-5, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22923244

RESUMEN

In Europe, a network for biological dosimetry has been created to strengthen the emergency preparedness and response capabilities in case of a large-scale nuclear accident or radiological emergency. Through the RENEB (Realising the European Network of Biodosimetry) project, 23 experienced laboratories from 16 European countries will establish a sustainable network for rapid, comprehensive and standardised biodosimetry provision that would be urgently required in an emergency situation on European ground. The foundation of the network is formed by five main pillars: (1) the ad hoc operational basis, (2) a basis of future developments, (3) an effective quality-management system, (4) arrangements to guarantee long-term sustainability and (5) awareness of the existence of RENEB. RENEB will thus provide a mechanism for quick, efficient and reliable support within the European radiation emergency management. The scientific basis of RENEB will concurrently contribute to increased safety in the field of radiation protection.


Asunto(s)
Protección Radiológica , Liberación de Radiactividad Peligrosa , Defensa Civil , Urgencias Médicas , Europa (Continente) , Humanos , Liberación de Radiactividad Peligrosa/prevención & control
20.
Radiat Prot Dosimetry ; 147(4): 573-92, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21183550

RESUMEN

The current focus on networking and mutual assistance in the management of radiation accidents or incidents has demonstrated the importance of a joined-up approach in physical and biological dosimetry. To this end, the European Radiation Dosimetry Working Group 10 on 'Retrospective Dosimetry' has been set up by individuals from a wide range of disciplines across Europe. Here, established and emerging dosimetry methods are reviewed, which can be used immediately and retrospectively following external ionising radiation exposure. Endpoints and assays include dicentrics, translocations, premature chromosome condensation, micronuclei, somatic mutations, gene expression, electron paramagnetic resonance, thermoluminescence, optically stimulated luminescence, neutron activation, haematology, protein biomarkers and analytical dose reconstruction. Individual characteristics of these techniques, their limitations and potential for further development are reviewed, and their usefulness in specific exposure scenarios is discussed. Whilst no single technique fulfils the criteria of an ideal dosemeter, an integrated approach using multiple techniques tailored to the exposure scenario can cover most requirements.


Asunto(s)
Monitoreo de Radiación , Radiación Ionizante , Radiometría/métodos , Carga Corporal (Radioterapia) , Humanos , Dosis de Radiación , Estudios Retrospectivos , Medición de Riesgo
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