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1.
J Chromatogr A ; 1081(1): 48-54, 2005 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-16013597

RESUMEN

The polyphenols (some of them are also called phytoalexins, flavonols, flavanons, flavanonols, flavons, flavanols, and anthocyanines) are usually marked as potent antioxidants or radical scavengers which assist the body cells against oxidation. Polyphenols in wine are also considered to explain so called French paradox (long life aging and low number of coronary diseases despite of high alcohol and fat consumption). The total polyphenolic content (TPC) and total antioxidant potential (TAP) were determined by photometry and found strongly correlated. This finding suggests that the determination of TAP can be replaced by a more simple procedure of TPC determination. Capillary zone electrophoresis (CZE) with preconcentration by solid phase extraction (SPE) was applied for some polyphenols determination and for obtaining electropherograms of the SPE extracts (fingerprints). From mathematical evaluation of the fingerprints, prediction of cultivars and vintage using artificial neural networks (ANN) was done with more than 90% correct prediction. The study was performed on a set of 47 samples of young wines (vintage 1999-2002) from south Moravia (Czech Republic) and New South Wales (Australia).


Asunto(s)
Antioxidantes/análisis , Electroforesis Capilar/métodos , Flavonoides/análisis , Redes Neurales de la Computación , Fenoles/análisis , Vino/análisis , Vino/clasificación , Flavonoides/aislamiento & purificación , Fenoles/aislamiento & purificación , Fotometría/métodos , Polifenoles
2.
J Chromatogr B Biomed Sci Appl ; 760(1): 37-43, 2001 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-11522064

RESUMEN

A new Capillary Zone Electrophoresis (CZE) procedure for determination of esmolol, an ultra-short-acting beta-blocker, in serum was developed. Dichloromethane was applied as a deproteination agent and it was used also for the inactivation of erythrocytal esterase and in the same time for the extraction of esmolol from blood. The re-extraction of esmolol from organic phase to water phase was performed by 0.01 M HCl. An aliquot of 200 ml of acid aqueous phase was used for the injection and analysis. CZE determination was done in 50 mM phosphate buffer (pH=8.0) with detection at 222 nm. The concentration detection limit of esmolol in serum was 0.051 microg/ml. This method was applied in an extensive heart surgery experiment on pigs (Sus scrofa).


Asunto(s)
Antagonistas Adrenérgicos beta/sangre , Monitoreo de Drogas/métodos , Electroforesis Capilar/métodos , Propanolaminas/sangre , Procedimientos Quirúrgicos Torácicos , Humanos , Sensibilidad y Especificidad , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
3.
Mutat Res ; 445(2): 285-93, 1999 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-10575437

RESUMEN

In the present study, we summarize the results of studies on the mutagenic potential of the main fractions and subfractions of extractable organic material (EOM) in the ambient air at the workplaces of the coke oven. The objective of our experiments was to apply the Bioassay-Directed Chemical Analysis (with the use of the Ames test) for the identification of the differences in the mutagenicity of these fractions, in relationship to the complex mixture of EOM in occupational air. From the evaluation of results, it is possible to deduce the following conclusions: (1) The comparison of the mutagenicity in the main fractions (basic, acidic, neutral) demonstrates the existence of differences in mutagenic potential. Of the total mutagenicity, 20.4% is in the basic fraction, 25.4% in the acidic fraction and 54.2% in the neutral fraction. (2) In general, 90.1% of the mutagenicity found in the basic, acidic and neutral fractions together was associated with the requirement of metabolic activation in vitro (+S9). In the case of the neutral fraction, it was 51.8%. (3) These results also suggest that frameshift mutations are the major component (53.8%) of the total mutagenicity of the main fractions. (4) With regards to the mutagenicity of organic compounds in the neutral fraction it appeared that genotoxicants of its subfractions (slightly and moderately polar and aromatic) play the main role. Carcinogenic aromatic hydrocarbons (PAH) and genotoxic nitrocompounds play an important role as determinants of the mutagenic potential of complex mixtures of harmful compounds in ambient air. This is confirmed first by the results of short-term bacterial tests.


Asunto(s)
Contaminantes Ocupacionales del Aire/efectos adversos , Contaminantes Ocupacionales del Aire/análisis , Coque , Monitoreo del Ambiente/métodos , Mutágenos/efectos adversos , Mutágenos/análisis , Hidrocarburos Policíclicos Aromáticos/efectos adversos , Hidrocarburos Policíclicos Aromáticos/análisis , Animales , Bioensayo , Biotransformación , Fraccionamiento Químico , Cromatografía de Gases , Microsomas Hepáticos/metabolismo , Pruebas de Mutagenicidad , Ratas , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo
4.
Mutat Res ; 417(1): 9-17, 1998 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-9729241

RESUMEN

Cytogenetic markers (chromosomal aberrations, sister chromatid exchanges (SCE), cells with high frequency of SCE (HFC), the heterogeneity index SCE (SCE-H) and genetic polymorphism of genotypes GSTM1 and NAT2 were evaluated in the peripheral lymphocytes of 64 coke oven workers and 34 control subjects from the same plant. Personal monitors were used to evaluate exposure to eight carcinogenic (polycyclic aromatic hydrocarbons) PAHs, including B[a]P, during an 8-h working shift. Smoking habits were checked by urinary cotinine measurement. The exposure among coke oven workers ranged widely from 0.6 to 547 microgram/m3 and 2 to 50 137 ng/m3, for carcinogenic PAHs and B[a]P, respectively. The respective values in controls were 0.07 to 1.51 microgram/m3 and from 2 to 63 ng/m3. The results of biomonitoring in exposed vs. control subjects were as follows: frequency of chromosomal aberrations (% AB.C.), 2. 30% AB.C. vs. 1.09% AB.C. (P<0.05); sister chromatid exchanges, 7.47 SCE/cell vs. 5.49 SCE/cell (P<0.05); HFC, 5.94% vs. 2.06% (P<0.05) and SCE-H index, 1.49 vs. 1.01 (P<0.05). All the cytogenetic markers were significantly increased in the exposed vs. control groups. The effect of smoking was observed only in SCE when evaluated as HFC. Using individual exposure data for carcinogenic PAHs, a significant correlation between exposure and %AB.C. (r=0.372, P=0.0002), SCE/cell (r=0.331, P=0.001), HFC (r=0.467, P=0.007) and SCE/H (r=0. 286, P=0.004) was found. No effects of GSTM1 and NAT2 genotypes, individually or in combination, on the cytogenetic markers was observed. It is concluded that occupational exposure of coke oven workers involved in this study resulted in an increased level of chromosomal aberrations and SCE. The frequency of AB.C. and SCE/cell was found to be related to exposure to carcinogenic PAHs.


Asunto(s)
Aberraciones Cromosómicas , Coque/efectos adversos , Mutágenos/efectos adversos , Exposición Profesional , Intercambio de Cromátides Hermanas , Arilamina N-Acetiltransferasa/genética , Estudios de Casos y Controles , Relación Dosis-Respuesta en la Radiación , Marcadores Genéticos , Glutatión Transferasa/genética , Humanos , Masculino , Hidrocarburos Policíclicos Aromáticos/efectos adversos , Polimorfismo Genético , Fumar
5.
Mutat Res ; 416(1-2): 67-84, 1998 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-9725993

RESUMEN

The DNA adduct levels in total white blood cells (WBC) and lymphocytes (LYM) isolated from the blood of the same individuals were evaluated using the 32P-postlabelling assay for bulky aromatic adducts. In this study, 68 male coke oven workers and 56 machines workers as a matched control were enrolled. Personal monitors were used to evaluate exposure to eight carcinogenic PAHs, including B[alpha]P, during an 8-h working shift. The exposure among coke even workers ranged widely from 0.6 to 547 micrograms/m3 and from 2 to 62,107 ng/m3, for carcinogenic PAHs and B[alpha]P, respectively. The respective values in controls were from 0.07-1.64 microgram/m3 and from 1-63 ng/m3. A significant correlation between WBC- and LYM-DNA adduct levels was found (r = 0.591, P < 0.001). DNA adduct levels in both WBC and LYM were significantly elevated in coke oven workers as compared with controls, but adduct levels were generally low (WBC: medians 2.61 vs. 1.83 LYM: 2.47 vs. 1.65 adducts/10(8) nucleotides). LYM-DNA adduct levels were significantly higher for smokers as compared with nonsmokers in both the exposed and control groups. No such differences in WBC-DNA adduct levels were observed. Positive significant correlations were found at the individual level between DNA adducts in both cell types and carcinogenic PAHs and/or B[alpha]P in the inhaled air (r = 0.38-0.45, P < 0.001). A significant correlation at the individual level between LYM-DNA adducts and urinary cotinine was also observed (r = 0.37, P < 0.001). No differences in DNA adduct levels could be attributed to GSTM1 or NAT2 genotype in either group. Nor was there any clear association of DNA adduct levels with combined GSTM1/NAT2 genotypes. The effect of personal exposure to carcinogenic PAHs on DNA adduct levels in both cell types was also investigated using a logistic regression model with adjustment for possible modulating effect of confounders (smoking, GSTM1, NAT2, age, plasma levels of vitamins A and E, body mass index and diet). The results showed that coke oven workers had a significantly (P < 0.05) increased adjusted Odds Ratio (OR = 4.2 and 3.9 for WBC and LYM-DNA adducts) for occurrence of higher DNA adduct levels as compared to controls. The results also showed that the relative risk of an increased prevalence of 'abnormal' values of DNA adduct levels was exposure-dose related. The influence of confounding variables was found not to be significant in this study of relatively limited size. In spite of this, the results suggest that the DNA adduct levels in LYM seem to be affected by smoking (OR = 1.8 for smokers) and are modulated by the influence of NAT2 genotypes (OR = 1.6 for slow acetylators). Our findings indicate that both cell types are generally suitable to monitor occupational exposure to PAHs, and the results suggest that coke oven workers, smoking individuals and slow acetylators sustain more genetic damage in their LYM-DNA from exposure to carcinogenic PAHs than individuals without these actors.


Asunto(s)
Coque/efectos adversos , Aductos de ADN/sangre , Aductos de ADN/efectos de los fármacos , Exposición Profesional , Adulto , Arilamina N-Acetiltransferasa/genética , Estudios de Casos y Controles , Cotinina/orina , Genotipo , Glutatión Transferasa/genética , Humanos , Leucocitos/química , Leucocitos/efectos de los fármacos , Modelos Logísticos , Linfocitos/química , Linfocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Radioisótopos de Fósforo , Hidrocarburos Policíclicos Aromáticos/efectos adversos , Vitaminas/sangre
6.
Artículo en Inglés | MEDLINE | ID: mdl-7008519

RESUMEN

Therapeutic electrical stimulation of nucleus caudatus was performed in 26 patients suffering from epilepsy. Sixteen of them had previously undergone destructive stereotactic surgery in different deep brain structures and the stimulation was indicated as an additional procedure. The results reported are related to 10 patients stimulated without any other surgical treatment. In 3 subjects stimulation of temporal lobe structures was performed as well. Good therapeutic effects were obtained in 2 cases following caudate stimulation. Mild improvement or no effect were obtained in the other cases, including the two submitted to hippocampal stimulation. Interesting speculation on the relationships between caudate and hippocampal electrical activity have been generated.


Asunto(s)
Núcleo Caudado , Terapia por Estimulación Eléctrica , Epilepsia/terapia , Adolescente , Adulto , Núcleo Caudado/fisiopatología , Epilepsia/fisiopatología , Epilepsia/cirugía , Femenino , Hipocampo/fisiopatología , Humanos , Masculino , Técnicas Estereotáxicas
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