Biomedical subjects

C Krause

Publications and source records attributed to C Krause.

80 records · Page 5Linked to original sources

PubMedDate not supplied

The German Environmental Survey 1990/1992 (GerES II): a representative population study.

The German Environmental Survey (GerES) is a large-scale population study which has repeatedly been carried out in Germany. GerES I was conducted in 1985/1986 followed by GerES IIa in 1990/1991 (West Germany) and GerES IIb in 1991/1992 (East Germany). GerES III is currently run in both parts of Germany. The main goal of the surveys is to analyse and document the extent, distribution and determinants of the exposure to environmental pollutants of the German general population. Field work is conducted using a combination of several tools, including questionnaires, interviews, human biomonitoring, and indoor and outdoor environmental samplings. This paper describes the design of GerES II, and gives a general outline of the field work and the analytical procedures used. In GerES II, about 4000 adults were representatively selected from the German population with regard to age, gender and community size. Approximately 700 children were also included. Arsenic, cadmium, copper, chromium, lead, and mercury were determined in blood, morning urine and/or scalp hair. In addition, samples were taken and analysed to characterise exposure in the domestic environment (indoor air, house dust, drinking water). The contribution to exposure of food was also studied. Exposure to volatile organic compounds (VOCs) was determined by personal sampling.

Adolescent↗

PubMedDate not supplied

The German Environmental Survey 1990/1992 (GerES II): cadmium in blood, urine and hair of adults and children.

As a follow-up of an earlier population study carried out in West Germany in 1985/1986 (GerES I), a nationwide Environmental Survey was conducted in Germany in 1990-1992 (GerES II). It was the aim of these studies to obtain representative data on the population's body burden and the quality of their indoor environment and immediate surroundings. The present paper reports on cadmium levels in blood, urine and hair of 4021 adults aged 25-69 and 736 children aged 6-14. The statistical analysis included both descriptive and inferential methods. The data were classified according to social factors, lifestyle characteristics, and environmental exposures. Moreover, regression analysis was used to determine the predictors of cadmium concentrations in the types of sample studied. Active cigarette smoking was found to be dominant in affecting blood and urine cadmium levels in adults, but less important for cadmium levels in hair. Age and creatinine level in urine were additional important factors influencing the cadmium concentration in urine, especially in women. Environmental and occupational exposures to cadmium played only a minor role in the exposure models for German adults. The cadmium concentration in blood and urine was generally lower in children than in adults, while no significant difference for cadmium in hair could be detected. The cadmium concentrations in all three samples were significantly higher in East German children than in West German children.

Adolescent↗

PubMedDate not supplied

The German Environmental Survey 1990/92 (GerES II): sources of personal exposure to volatile organic compounds.

In the framework of the second German Environmental Survey carried out in the Western part of Germany in 1990/91 (GerES IIa) 113 adults aged 25-69 years were selected at random from the total study population of about 2500 to investigate personal exposure to about 70 volatile organic compounds (VOCs). Each subject wore a diffusive badge-type sampler for 1 week. The VOCs determined included alkanes, aromatics, aliphatic halocarbons, terpenes, and oxygen-containing compounds. Multivariate regression analysis was carried out to determine and quantify the major sources of personal exposure to various VOCs. In this paper, results are given for benzene, and C8- and C9-aromatics. Being subject to environmental tobacco smoke was found to be the most important determinant of benzene exposure, but automobile-related activities such as driving a car or refuelling, were also associated with significantly increased levels of benzene. The major determinant of C8- and C9-aromatics concentrations was occupational exposure. Emissions from paints, lacquers, newspapers, magazines and print-works were also important contributors to C8-aromatics exposure. Renovation, painting and smoking were associated with a significant increase of the exposure to C9-aromatics.

Adult↗

PubMedDate not supplied

The German Environmental Survey 1990/1992 (GerES II): reference concentrations of selected environmental pollutants in blood, urine, hair, house dust, drinking water and indoor air.

The German Environmental Survey (GerES) is a large-scale, representative population study that has been carried out three times up to now with a time interval of about 7 years. GerES I was performed in 1985/1986, GerES IIa in 1990/1991 in West Germany, and GerES IIb in 1991/1992 in East Germany, the former German Democratic Republic (GDR). In GerES II, blood, urine, and scalp hair samples of 4021 adults aged 25-69 years and of 736 children aged 6-14 years were analysed as well as environmental samples (house dust, drinking water, indoor and personal air, diet). Characteristics of the frequency distributions of the substances analysed in the different media were calculated. The geometric mean (GM) for lead, cadmium, and mercury in the blood of adults amounted to 45.3, 0.36, and 0.51 microg/l, respectively. The corresponding values of arsenic, cadmium, and mercury in urine were 6.3, 0.29, and 0.54 microg/l, respectively. The concentrations of lead in blood, cadmium in blood and urine, and mercury in blood are lower in children than in adults. The GM ofpentachlorophenol (PCP) in urine of adults was 2.67 microg/l and in urine of children, 4.15 microg/l. These results of GerES II were compared with the so-called HBM values which represent health-based exposure guidelines and have been defined by the Human Biomonitoring Commission (HBC) of the Federal Environmental Agency, interalia for lead in blood, cadmium in urine, mercury in blood and urine, and PCP in urine. They also provided asound basis for the setting of reference values to describe the status of the German population. A total of 1.8% and 0.6% of the German females in child-bearing age had a level of lead in blood higher than HBM-I (100 microg/l) and HBM-II ( 150 microg/l), respectively. One percent of the children had a blood lead level above HBM-I. House dust and drinking water were analysed to characterise exposure in the domestic environment. Arsenic, cadmium, and lead deposition in homes amounted to 5.4 ng/(m2 day), 11.7 ng/(m2 day), and 0.29 microg/(m2 day), respectively. In the content of vacuum cleaner bags, concentrations were 2.1,0.9, and 5.9 microg/g. PCP, lindane and permethrin could be detected in the house dust of most German households. The pollutant load of the drinking water is significantly influenced by the corrosion of pipe materials and fittings. The new EC limit value of 10 microg/l for lead was exceeded in 7.7% of the first draw samples. The relatively high percentage (14%) of samples from East Germany that exceeded the current German guideline value for formaldehyde of 0.1 ppm in indoor air may be explained by the widespread use of contaminated particleboard in the former GDR.

Adolescent↗

PubMedDate not supplied

The German Environmental Survey 1990/92 (GerES II): primary predictors of blood cadmium levels in adults.

As part of the representative Environmental Survey in Germany in 1990-1992, investigators determined cadmium levels in blood provided by 3,965 subjects aged 25-69 yr. The investigators considered approximately 150 variables (i.e., demographics, household and occupational characteristics, environmental exposures, smoking habits, frequency of food consumption, and additional life-style features) as potential predictors in multivariate regression analysis. On the basis of the results of multivariate regression analysis, the authors derived 2 slightly different models for the prediction of blood cadmium levels in populations from West and East Germany. Both models included 3 primary predictors of blood cadmium levels. The 2 models explained 51.3% and 61.2% of the observed variance in blood cadmium levels in West and East Germany, respectively. The most important predictor was a specific indicator for smoking habits, which was determined from a separate mathematical model. In this model, the effect of smoking was considered, and the model accounted for the biological half-life of cadmium in blood.

Adult↗

PubMedDate not supplied

Factors affecting internal mercury burdens among eastern German children.

Internal burdens of mercury were evaluated among 5- to 14-y-old eastern German children in the heavily polluted areas of Bitterfeld, a center of chemical production and coal mining, and Hettstedt, a region of nonferrous metal smelting and mining. We compared blood and urine mercury concentrations in these children with mercury burdens in children who lived in a control area. The unadjusted geometric means of mercury levels in the total group were 0.25 microg/l (95% confidence interval = 0.24, 0.27) in blood and 0.36 microg mercury/g creatinine (95% confidence interval = 0.33, 0.39) in urine. Mercury levels in blood and urine were not significantly higher in children who occupied the two polluted areas, compared with children in the control area. The most significant factor that affected urinary mercury levels was the number of dental amalgam fillings; 27% of the variance in the regression model was explained by the presence of these fillings.

Adolescent↗

PubMedDate not supplied

Effect of cadmium body burden on immune response of school children.

The effects of cadmium on measures of immune-system function were determined from a health survey of school children in heavily polluted regions of eastern Germany. A representative sample of 842 students, aged 5-14 y, was included in logistic regression analyses in which the relationship between urinary cadmium content and blood immunoglobulin levels was examined. Investigators further evaluated a subsample of 807 students to determine cadmium's effect on the immediate hypersensitivity reactions elicited by skin-prick challenges with 12 common aeroallergens. Several potentially confounding factors were controlled for, after which investigators found that increasing body burdens of cadmium were associated consistently with dose-dependent suppression of immediate hypersensitivity and of immunoglobin G, but not immunoglobulins M, A, or E levels. The immunoglobulin pattern observed in exposed children led investigators to suggest that secondary humoral responses were impaired by cadmium.

Adolescent↗

PubMedDate not supplied

TRAIL-induced cytotoxicity in a melphalan-resistant rhabdomyosarcoma cell line via activation of caspase-2.

The prognosis for patients with chemo-refractory rhabdomyosarcoma remains poor. The tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is a hopeful candidate for new strategies in chemotherapy. The effects of TRAIL and melphalan (Mel) in the rhabdomyosarcoma cell line TE-671 were investigated by colorimetric caspase assays and flow cytometry. TRAIL induced the activation of caspases-2, -3 and -8, but not the activation of caspase-9, in the Mel-resistant TE-671 cells. Inhibition of caspase-2 with the caspase-2 inhibitor z-VDVAD-fmk significantly down-regulated the TRAIL-induced caspase-3 activation, as well as the TRAIL-induced cytotoxicity. When TE-671 cells were treated with a combination of Mel and TRAIL, a significant synergism of drug-induced cytotoxicity was obtained. The inhibition of caspase-2 could completely abolish caspase-3 activation, suggesting that TRAIL sensitises TE-671 cells for Mel-induced cytotoxicity via a caspase-2- and -3-dependent mechanism. In conclusion, it was shown, for the first time, that TRAIL could sensitise Mel-resistant tumour cells to melphalan.

Antineoplastic Combined Chemotherapy Protocols↗