Cardiovascular reaction to job stress in middle-aged train drivers.

In this study, cardiovascular (CV) response to a standard laboratory challenge was compared to 24-hr noninvasive monitoring of heart rate (HR) and blood pressure (BP) in 30 healthy middle-aged train drivers. Laboratory stress test consisted of the orthostatic test, the cold pressor test, the Valsalva maneuver, the Stroop test, and the numerical square. In addition, the participants completed an extensive questionnaire on their health state and family health history, lifestyle, job stress, social and family support, personality characteristics, and health risk behaviors.

Studies on the methyl isocyanate adducts with globin.

Isocyanates such as methylisocyanate (MIC), an intermediate in the synthesis of carbamate pesticides, or diisocyanates, used in the production of plastics, are highly reactive toxic compounds that spontaneously bind to biological macromolecules. In vivo formation of stable adducts with blood protein globin offers possibilities for biomonitoring of internal exposure to various reactive species. Thus, biomonitoring of the isocyanates through determination of their specific adducts with globin is a challenge.

Acute toxicity of binary mixture benzene-ethanol and partition coefficient K(ow) of benzene and ethanol.

The study related to partition coefficients between n-octanol and water of compounds in binary mixture benzene-ethanol was carried out. Partition coefficients of benzene and ethanol for different values of molar ratio of benzene in the mixture were determined. Collected results show statistically significant deviations the K(ow) of benzene for some molar ratios (0.

Lung function impairment in relation to asbestos-induced pleural lesions with reference to the extent of the lesions and the initial parenchymal fibrosis.

Objectives: The study focused on the effect of pleural lesions on the lung function of asbestos-exposed workers.

Methods: A clinical check-up, chest radiography, high-resolution computed tomography (HRCT), and lung function testing were performed on 162 asbestos-exposed workers without any sign of parenchymal fibrosis on their chest radiographs. According to the HRCT scans, two subgroups were delineated, 97 subjects with pleural lesions and 65 referents without pleural lesions.

Improved chelation therapy of intramuscularly deposited thorium by CaDTPA in the rat.

Comparative studies on the translocation and retention of intramuscularly (i.m.) injected thorium nitrate (234Th 46 ng + 232Th 5 microg per rat) in solutions of citrate, CaDTPA or citrate + CaDTPA in rats have been conducted.

Biological monitoring of N, N-dimethylformamide. Reference value for N-methylcarbamoyl adduct at the N-terminal valine of globin as a biomarker of chronic occupational exposure.

Objectives: The recently identified metabolic product of the industrial solvent N, N-dimethylformamide (DMF), the N-methylcarbamoyl adduct at the N-terminal valine of globin, can be determined after chemical conversion to 3-methyl-5-isopropylhydantoin (MVH). Due to prolonged persistence of the adduct in human erythrocytes (lifetime: 4 months), MVH is a suitable biomarker of integrated exposure to DMF over a period of several months. Here we propose a reference value for MVH, used for biological monitoring of chronic occupational exposure to DMF.

Improved gas chromatographic-mass spectrometric determination of the N-methylcarbamoyl adduct at the N-terminal valine of globin, a metabolic product of the solvent N,N-dimethylformamide.

A sensitive method for determination of the N-methylcarbamoyl adduct at the N-terminal valine of globin, a new metabolic product of the industrial solvent N,N-dimethylformamide (DMF), has been developed and validated. The method includes conversion of the adduct by the Edman degradation to 3-methyl-5-isopropylhydantoin (MVH), which is followed by optimized gas chromatographic analysis with mass spectrometric detection at m/z 114. The recovery of MVH from terminal N-methylcarbamoylvaline was determined using a model dipeptide to be 90%.

Effect of oral ZnDTPA on late effects of injected plutonium in rat.

Purpose: To reduce the long-term toxicity of 239Pu in rats by lifetime drinking of ZnDTPA solution and to investigate possible side-effects of the drug.

Materials And Methods: Male Sprague-Dawley rats received a single injection of 239Pu citrate, alone or plus oral ZnDTPA. Additional groups were administered only ZnDTPA.

Cytotoxicity of cyclophosphamide, paclitaxel, and docetaxel for tumor cell lines in vitro: effects of concentration, time and cytochrome P450-catalyzed metabolism.

Cytotoxic effects of cyclophosphamide (CPA), paclitaxel (PCT), and docetaxel (DTX) and their modulation by cytochrome P450 (CYP) metabolism were studied by incubating cell lines L929 and P388D1 with or without rat liver microsomes. The microsomes themselves were not cytotoxic. P388D1 cells were more sensitive to CPA, PCT, and DTX than L929 cells.

Mobilization and detoxification of polonium-210 in rats by 2,3-dimercaptosuccinic acid and its derivatives.

Purpose: To reduce retention and toxicity of the alpha particle emitter polonium-210 in rats by newly developed chelating agents.

Materials And Methods: Repeated subcutaneous chelation was conducted after intravenous injection of 210Po nitrate. For reduction of 210Po retention the treatment with vicinal dithiols meso-and rac-2,3-dimercaptosuccinic acid (DMSA), mono-i-amylmeso-2,3-dimercapto succinate (Mi-ADMS) and mono-N-(i-butyl)-meso-2,3-dimercapto succinamide (Mi-BDMA) were used.

Effect of ethanol on the urinary excretion of cyclohexanol and cyclohexanediols, biomarkers of the exposure to cyclohexanone, cyclohexane and cyclohexanol in humans.

Objectives: This study explored the acute effect of ethanol (EtOH) on the urinary excretion of cyclohexanol (CH-ol), 1,2- and 1,4-cyclohexanediol (CH-diol), biomarkers of exposure to important solvents, and chemical intermediates cyclohexanone (CH-one), cyclohexane (CH) and cyclohexanol.

Methods: Volunteers (5-8 in each group) were exposed for 8 hours either to CH-one, CH or CH-ol vapor at concentrations of about 200, 1000, and 200 mg/m3, respectively, with concomitant ingestion of EtOH (4 14-g doses taken during the exposure). Urine was collected for 72 hours and analyzed for CH-ol and CH-diols using a procedure involving acidic hydrolysis and gas chromatographic determination.

2,4-toluenediisocyanate and hexamethylene-diisocyanate adducts with blood proteins: assessment of reactivity of amino acid residues in vitro.

Diisocyanates, reactive compounds used in plastics industry and potent occupational allergens, readily bind to proteins both in vitro and in vivo, however, the pattern of adducts with individual amino acids has not been investigated systematically. In this study, potential of the proteinogenic amino acid residues for carbamoylation with 2,4-toluenediisocyanate (2,4-TDI) and hexamethylenediisocyanate (HDI) was evaluated. The diisocyanates were incubated in an in vitro system (buffer pH 7.

Biliary iron excretion in rats following treatment with analogs of pyridoxal isonicotinoyl hydrazone.

Iron overload is a major life-threatening complication of thalassemia major and other iron-loading anemias treated by regular blood transfusions. Although the clinical manifestations of iron overload may be prevented by desferrioxamine, the only iron-chelating drug in routine clinical use, this treatment requires subcutaneous infusion of desferrioxamine for 12 hours each day. New orally effective iron chelators are urgently needed, and pyridoxal isonicotinoyl hydrazone (PIH), which was first recognized as an effective iron chelator in vitro and subsequently in vivo, shows promise for the treatment of iron overload.

Reduction of subacute lethal radiotoxicity of polonium-210 in rats by chelating agents.

The protective effect of N,N'-di(2-hydroxyethyl)ethylene-diamine-N,N'-biscarbodithioate (HOEtTTC) against the subacute lethal radiotoxicity of polonium-210 was investigated in a survival study and by histopathological and haematological examinations of some organs and tissues in Sprague-Dawley rats. This effect was compared with that of N,N'-diethylamine-N-carbodithioate (diethy dithiocarbamate, DDTC). In the survival study, rats injected in intravenously solely with a lethal amount of 210Po (1.

Effect of 50-Hz electromagnetic field on the retention of toxic radionuclides in rat tissues.

The effect of electromagnetic field (EMF) 50 Hz, 10 mT, on the tissue retention of radiotoxic polonium-210 and thorium-234 was studied in a rat model. Regarding 210Po in the ionic state, small but significant effects were obtained by exposure of rats to EMF either before the intravenous injection of 210Po (pre-exposure) or after the rats had already been injected with 210Po (post-exposure). When compared with control values, pre-exposure to EMF caused a significant 28% decrease in the retention of 210Po in the skin and a 10% decrease in total 210Po retention in the investigated tissues.

The evidence for conjugated mandelic and phenylglyoxylic acids in the urine of rats dosed with styrene.

Male Wistar rats were dosed intraperitoneally with styrene (400 mg/kg). Urine samples were collected over phosphate buffer, pH 6.5 for 24 h.

Pattern of inhalation exposure: blood levels and acute subnarcotic effects of toluene and acetone in rats.

Solvent blood concentrations and subnarcotic effects (inhibition of electrically evoked seizures) were measured in rats exposed to constant or fluctuating air concentrations of toluene or acetone. A 4 hour exposure of resting rats to toluene at an air concentration of 1 and 2 mg/l, or to acetone at 4 and 10 mg/l, led to blood levels of 6.7 and 12.

Chelation therapy by DFO-HOPO and 3,4,3-LIHOPO for injected Pu-238 and Am-241 in the rat: effect of dosage, time and mode of chelate administration.

The effectiveness of the siderophore analogues DFO-HOPO (a hydroxypyridone derivative of desferrioxamine) and 3,4,3-LIHOPO (a linear tetrahydroxypyridinone) for the decorporation of 238Pu and 241Am from rat was studied. (1) Dosage-effect relationship. A similar treatment effect on Pu was achieved by single s.

Effects of magnetic field exposure on the development of lung fibrosis elicited by industrial pollutants.

Lung injury elicited by a single intratracheal instillation of fibrogenic (quartz) and nuisance (anatase) dusts and/or weekly repeated instillation of CdCl2 solution combined with sinusoidal (50 Hz, 10 mT) magnetic field (MF) exposure was studied in male rats. Combined effects in bronchoalveolar lavage (BAL), rat lungs and regional lymph nodes after 4 months of MF exposure (1 h/5 days per week) were evaluated biochemically and by cytological and histopathological examination. Damage of cell membranes in the cell part of BAL due to MF exposure was not observed in the examined animal groups.

Treatment with 3,4,3-LIHOPO of simulated wounds contaminated with plutonium and americium in rat.

The effect of a siderophore analogue 3,4,3-LIHOPO has been investigated in rat after intramuscular injection of 238Pu, 239Pu and 241Am simulating puncture wounds. Various treatment regimens were used to remove the radioactivity from its injection site and to reduce its retention in body tissues. The local deposits could be reduced to 9% of that in untreated controls by a single local injection of 30 mumol kg-1 3,4,3-LIHOPO administered 1 day after the actinides.

Biotransformation of acrolein in rat: excretion of mercapturic acids after inhalation and intraperitoneal injection.

Biotransformation of acrolein (ACR) was studied in vivo in the rat following inhalation and ip administration. The major and minor urinary metabolites were 3-hydroxypropylmercapturic acid (HPMA) and 2-carboxyethylmercapturic acid (CEMA), respectively. Male Wistar rats were exposed to ACR, 23, 42, 77 and 126 mg/m3, for 1 hr.

Vigilance impairment after a single dose of benzodiazepines.

While outpatients or other users of therapeutic drugs have to be informed about the risk of impaired functioning during driving or work, the prescribing physician needs to be familiar with the side effects of alternative drugs in order to select the most suitable treatment. With this aim, several types of benzodiazepine anxiolytics in low anxiolytic doses (diazepam 5 mg or 10 mg, nitrazepam 5 mg, oxazepam 10 mg, medazepam 10 mg, and alprazolam 0.2 or 0.

Neutrotropic effects and blood levels of solvents at combined exposures: binary mixtures of toluene, o-xylene and acetone in rats and mice.

Male rats and female mice were exposed to vapours of toluene, o-xylene and acetone in basic or double concentrations or to binary combinations of basic concentrations, for 4 and 2 hours, respectively. Basic air concentrations were for rats and mice (in ppm): toluene 270 and 380, o-xylene 230 and 320, acetone 1700 and 1530, respectively. The CNS effect-inhibition of electrically evoked seizure discharge-was measured immediately after exposure and blood levels of solvents were monitored during the desaturation phase.

Biotransformation of acrylates. Excretion of mercapturic acids and changes in urinary carboxylic acid profile in rat dosed with ethyl and 1-butyl acrylate.

1. The excretion of urinary metabolites was studied in rat dosed intraperitoneally with ethyl acrylate and 1-butyl acrylate. 2.