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1.
J Int Med Res ; 39(2): 499-507, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21672353

RESUMO

This prospective randomized study investigated the effects of two different cardioplegia techniques on myocardial heat shock protein 70 (HSP70) mRNA levels. Patients undergoing elective coronary artery bypass grafting with cardiopulmonary bypass (CPB) were divided into two equal groups. All patients received the same anaesthesia. Myocardial preservation was achieved by delivering intermittent antegrade isothermic blood cardioplegia in one group and antegrade plus continuous retrograde isothermic blood cardioplegia in the other. Biopsies for measurement of HSP70 mRNA levels were taken from the right atria before surgical manipulation of the heart, and later from the same place following CPB. HSP70 mRNA levels were evaluated using quantitative real-time reverse transcription-polymerase chain reaction. Crossing-point values for HSP70 and ß-actin were used to evaluate up-regulation. There was a significant increase in HSP70 mRNA levels in response to CPB in both groups, but no significant between-group difference in HSP70 up-regulation. Further investigation is required to evaluate the correlation between the level of HSP induction and the degree of myocardial protection in more heterogeneous groups of patients.


Assuntos
Ponte Cardiopulmonar , Proteínas de Choque Térmico HSP70/metabolismo , Miocárdio/metabolismo , Actinas/metabolismo , Ponte de Artéria Coronária , Demografia , Feminino , Proteínas de Choque Térmico HSP70/genética , Humanos , Masculino , Pessoa de Meia-Idade
2.
Gesundheitswesen ; 71(5): 275-80, 2009 May.
Artigo em Alemão | MEDLINE | ID: mdl-19294617

RESUMO

Polychlorinated biphenyls (PCB) were widely used in numerous industrial and commercial applications in high quantities in the past. Based on their persistence in the environment, their tendency to accumulate in the organism and their specific health effects, PCBs have to be assessed as critical substances. Because the dietary intake was assumed to be the main intake route, the Integrated Exposure Assessment Survey (INES) aimed to measure the recent exposure to PCBs in Germany. The study consisted of 10 female and 10 male participants living in Munich and surroundings. The participants collected dietary duplicates of all food consumed and prepared as for consumption over 7 consecutive days. Altogether the 6 non-dioxin-like PCB congeners 28, 52, 101, 138, 153 and 180 ndl-PCB or, respectively, indicator PCB and furthermore the congener 118 were detected using a gas chromatographic method. Dietary intake was calculated using the amount of food eaten daily and the results from the duplicates. Using the sum of PCB 138, 153 and 180 multiplied by 4, the daily intake ranged from 4.0 to 24.1 ng/kg b.w. (median: 9.5 ng/kg b.w.). On the contrary, the daily intake was 2.9 to 20.6 ng/kg b.w. (median: 11.2 ng/kg b.w.) if the sum of the 6 indicator PCBs multiplied by factor 2 was used for quantification. No sex-related difference of the dietary intake was observable. Overall, it can be concluded that the dietary PCB intake has further decreased in the last years in Germany. At present, the toxicological database is not suitable to assess the risks coming solely from the non-dioxin-like PCBs because it is not possible to differentiate between non dioxin-like and dioxin-like effects in toxicological studies. Nevertheless, a further reduction of PCB exposure via food by searching for possible sources is needed.


Assuntos
Dieta , Ingestão de Alimentos , Exposição Ambiental/análise , Poluentes Ambientais/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Bifenilos Policlorados/análise , Adulto , Coleta de Dados , Dioxinas/análise , Feminino , Alemanha , Humanos , Pessoa de Meia-Idade
3.
Int J Hyg Environ Health ; 210(3-4): 345-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17321208

RESUMO

The Integrated Exposure Assessment Survey (INES) was started in the year 2005. Altogether 50 healthy adults living in Bavaria, Germany, were included into the study. Monitoring was conducted in accordance with relevant routes of human exposure (inhalation, ingestion) and integrated different pathways (indoor air, food, house dust). This approach consisted of a combination of external measurements of contaminants with the determination of these substances or their metabolites in body fluids. The target substances were phthalates, perfluorinated compounds (PFC), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), and polybrominated diphenylethers (PBDEs). This paper gives a brief description of the objectives and the concept of INES as well as methods of sampling and analyses of target compounds. Some preliminary results of biomonitoring data for PFC and phthalates as well as of the dietary intake of DEHP will be discussed.


Assuntos
Poluentes Atmosféricos/metabolismo , Exposição Ambiental/análise , Monitoramento Ambiental , Adolescente , Adulto , Poluentes Atmosféricos/análise , Benzofuranos/sangue , Benzofuranos/urina , Estudos de Coortes , Dibenzofuranos Policlorados , Registros de Dieta , Poeira/análise , Feminino , Contaminação de Alimentos/análise , Alemanha , Éteres Difenil Halogenados , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Éteres Fenílicos/sangue , Éteres Fenílicos/urina , Ácidos Ftálicos/sangue , Ácidos Ftálicos/urina , Bifenilos Policlorados/sangue , Bifenilos Policlorados/urina , Dibenzodioxinas Policloradas/análogos & derivados , Dibenzodioxinas Policloradas/sangue , Dibenzodioxinas Policloradas/urina
4.
Anal Chim Acta ; 580(1): 83-90, 2006 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-17723759

RESUMO

Although the use of once widely applied selective herbicide, 4,6-dinitro-o-cresol (DNOC), was cancelled by US-EPA in 1987, it is still found in soil and water due to its slow degradation in the environment. Since solid phase extraction-spectrophotometry combinations are much simpler and cheaper than chromatography/MS based methods and most routine laboratories lack such sophisticated instrumentation, it is desirable to establish novel sensitive, well-established, and field-applicable spectrophotometric methods for the rapid assay of DNOC in water and soil. For this purpose, two distinct spectrophotometric methods utilizing the periodate and copper(II)-neocuproine (Nc) reagents have been developed following Zn/HCl reduction of the pesticide in a microwave oven for 15s, and validated for DNOC determination at mg L(-1) level. The LOD values were 1.6 and 0.2 mg L(-1) for periodate and Cu(II)-Nc methods, respectively. Statistical comparison of the developed methods was made with the aid of high performance liquid chromatography (HPLC) equipped with a C18 (5 microm), 250 mm x 4.6 mm ID reversed phase column in conjunction with a UV (264 nm) detector, and a methanol (HPLC grade) +0.1% glacial acetic acid mixture mobile phase. Both spectrophotometric methods were directly applicable to soil since they were not interfered with common soil cations and anions, together with some pesticides. These methods were applied to real samples such as synthetically contaminated montmorillonite and lemon juice, and overall recovery efficiencies at the order of 95% or greater were achieved in the devised adsorption/elution procedures. An 8-hydroxyquinoline (oxine)-impregnated XAD copolymer resin stabilized with Fe(III) salt was used to preconcentrate DNOC at a concentration factor of 20 from lemon juice contaminated with 1 mg L(-1) DNOC, and the analyte retained at pH 2.5 was eluted with 0.025 M methanolic NaOH. Both the devised spectrophotometric methods and the proposed preconcentration column with optimized sorption and desorption conditions are novel for DNOC assay in the natural environment.

5.
Chemosphere ; 44(4): 721-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11482661

RESUMO

The stability of eight environmentally relevant azo dye metabolites [o-aminotoluene (2), 4,4'-thiodianiline (4), 4,4'-diaminodiphenylmethane (6), p-chloroaniline (7), 2,4-toluylenediamine (9), p-kresidine (14), 2,4-diaminoanisole (15), and 2-naphthylamine (18)] was investigated in activated sludge systems and compared to their hydrolysis stability. For both studies, test systems of the EC and EPA were used. The results show that degradation under aerobic conditions proceeds via oxidation of the substituents located on the aromatic ring or on the side chain. Under anaerobic conditions, the azo bond is reductively cleaved, which leads to the substituted amines. These are toxic and potentially hazardous to the environment.


Assuntos
Compostos Azo/metabolismo , Poluentes Ambientais/metabolismo , Esgotos/química , Bactérias Aeróbias/fisiologia , Bactérias Anaeróbias/fisiologia , Hidrólise , Oxirredução
6.
Chemosphere ; 40(6): 685-9, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10705545

RESUMO

Fish samples of different origins have been analysed with short column gas chromatography-electron capture negative ion/mass spectrometry (SCGC/ECNI-MS). The influence of standards composed from different polychlorinated alkanes on the quantification of short chain polychlorinated paraffines (CP) was studied. Concentration values varied very differently with the response of the standards depending on their chlorination degree. The results show, that technical CP products should not be used as standard in most cases, because the composition of polychlorinated alkanes in fish is different from sample to sample.


Assuntos
Alcanos/análise , Peixes , Hidrocarbonetos Clorados/análise , Poluentes Químicos da Água/análise , Animais , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Gasosa-Espectrometria de Massas/normas , Parafina/química , Bifenilos Policlorados/análise
7.
Chemosphere ; 39(4): 563-8, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10422247

RESUMO

Toxaphene residues in cod liver and fish oil samples from different countries have been analyzed by HRGC-ECD and HRGC-MS as well as with multidimensional gas chromatography. The results have been compared to patterns obtained by photolysis and microbial degradation of selected single chlorobornanes and technical toxaphene. Enantiomeric ratios of the components Parlar #44 and #62 showed significant deviations from 1, indicating metabolism in cod fish and perhaps other species at least for some congeners. Parlar #50 was found to be a racemate, which corresponds to its known stability under biotic and abiotic conditions.


Assuntos
Inseticidas/farmacocinética , Toxafeno/farmacocinética , Poluentes Químicos da Água/farmacocinética , Animais , Biodegradação Ambiental , Peixes/fisiologia , Microbiologia da Água
8.
Chemosphere ; 39(4): 683-8, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10422255

RESUMO

Four chiral HRGC column systems for the separation of selected organochlor pesticides and photoconversion products (heptachlor, cis- and trans-chlordane, o,p'-DDT, o,p'-DDD, and alpha-HCH) were tested. Cod hver oil and fish oil samples from different countries were comparatively analyzed. Of all these columns, the fourth was the most suitable one for the analysis of the selected compounds. The enantiomer ratios [ER] of cis-chlordane, trans-chlordane, photodieldrin, alpha-HCH, and o,p'-DDD in fish oils are nearly 1.0, while the ERs of the same substances are significantly different from 1.0 in cod liver oils. Contrary to that, the ER values of o,p'-DDT are remarkable different from 1 in the cod liver oils as well as in the fish oils.


Assuntos
Cromatografia Gasosa/métodos , Peixes , Hidrocarbonetos Clorados , Inseticidas/química , Xenobióticos/química , Animais , Inseticidas/análise , Fígado/química , Sensibilidade e Especificidade , Poluentes Químicos da Água/análise , Xenobióticos/análise
9.
Chemosphere ; 36(15): 3119-35, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9747516

RESUMO

Three environmentally significant chlorinated bornane (CHB) congeners were extracted from Arviat ringed seal blubber and identified by using gas chromatography/mass spectrometry (HRGC/HRECNIMS (CH4), low resolution EIMS, and linked field scanning). They are referred to as TS2 (Parlar#39, B8-531) [2-exo,3-endo,5-exo,6,6,8b,9c,10c (or 10a)-octachlorobornane], TS3 (Parlar#40, B8-1414) [2-endo,3-exo,5-endo,6-exo,8c,9b,10a,10c (or 10b)-octachlorobornane] and TS4 (Parlar#42, Toxicant A, B8-806/809) [2-exo,3-endo,6,6,8b,8c,9c,10c (or 10a)-octachlorobornane/2-exo,3-endo,6,6,8b,9b,9c,10a (or 10b)-octachlorobornane]. This is the first time Toxicant A, known to be the most toxic CHB congener in technical toxaphene, has been found in any significant concentration in a marine mammal.


Assuntos
Inseticidas/análise , Focas Verdadeiras/metabolismo , Toxafeno/análise , Poluentes Químicos da Água/análise , Animais , Regiões Árticas , Canadá , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas/métodos , Inseticidas/química , Estrutura Molecular , Água do Mar , Toxafeno/química
11.
J Chromatogr B Biomed Appl ; 677(2): 245-55, 1996 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-8704928

RESUMO

Smoking or ingestion of cannabis causes cognitive, perceptual and behavioural changes, which are responsive for impaired performance in driving motor vehicles. In this paper a novel liquid chromatographic assay for the selective quantification of delta 9-tetrahydrocannabinol, the major indicator of a present cannabis intoxication in saliva, is described. The method involves a column-switching procedure and requires an extremely simple pre-treatment of the sample. Deproteinized saliva was directly injected into the chromatographic system. The clean-up and enrichment procedure was performed in an immunoaffinity column, followed by the transfer of the antigens to an octysilica analytical column. The immunoaffinity sorbent was obtained by covalent immobilization of specific antibodies on epoxy-activated silica. The mobile phase consisted of methanol-aqueous 0.15 mol/1 NaCl solution (elution programmed) and the analyte was detected by measuring the UV absorption at 220 nm. Using an injection volume of 4.5 ml (dilution 3:2, v/v) the limit of quantification was 20 ng/ml, at a signal-to-noise ratio of 5. Recoveries were estimated to be in the range of 70%. Both intra- and inter- day coefficients of variation were below 5%.


Assuntos
Cromatografia de Afinidade/métodos , Cromatografia Líquida de Alta Pressão/métodos , Dronabinol/análise , Saliva/química , Feminino , Humanos , Masculino , Valores de Referência , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta
12.
Z Lebensm Unters Forsch ; 192(5): 440-4, 1991 May.
Artigo em Alemão | MEDLINE | ID: mdl-2058313

RESUMO

When quantified by HPGC-ECD and HPGC-NCI-SIM commercially available standards of the insecticide Toxaphene show different detector responses, primarily depending on the percentage of chlorine in the mixtures. To obtain accurate results, residues of Toxaphene in environmental samples should be quantified by using a standard with a similar or nearly similar detector response. If this is not possible, any standard may be used but the results of the samples must be corrected afterwards. By comparing different integration methods, it can be seen that the best results are obtained by integrating as many single-peak areas as possible. Quantification by integration of the bulge formed by raising the baseline, which can be observed in many gas chromatograms of Toxaphene standards, should be avoided because this hump is caused by degradation of chlorobornanes under higher temperatures. The extent of this bulge depends both on temperature and the percentage of chlorine, the latter being generally lower in the samples as a result of transformation processes under environmental conditions. Therefore integration of the bulge or the whole area leads to lower results.


Assuntos
Resíduos de Drogas/análise , Óleos de Peixe/química , Toxafeno/análise , Animais , Canfanos/metabolismo , Cloro/análise , Cromatografia Gasosa
13.
Ecotoxicol Environ Saf ; 10(1): 120-7, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2992907

RESUMO

Reactions with water and 2 + 2-cycloadditions of individual bases are the primary steps held responsible for the deformation of DNA at short wavelengths. From the observed data however the influence of atmospheric oxygen on the light-induced reaction of DNA is evident. A plausible explanation for these effects is the formation of reactive oxygen species during the UV irradiation of DNA. In the present work the deformation of DNA by different oxygen species like singlet oxygen (1O2), superoxideanion (O2), hydroxyradical (OH.), and ozone (O3) is excluded with the help of chemical-trapping experiments. The photoinduced transformation proceeds via excited states of DNA, which react with oxygen to afford peroxide.


Assuntos
DNA/efeitos da radiação , Peróxidos , Fenômenos Químicos , Físico-Química , Concentração de Íons de Hidrogênio , Oxigênio , Fotólise , Superóxidos , Temperatura , Raios Ultravioleta
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