2. |
- Hagmar, L., et al.
(author)
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Intra-individual variations and time trends 1991-2001 in human serum levels of PCB, DDE and hexachlorobenzene
- 2006
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In: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 64:9, s. 1507-1513
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Journal article (peer-reviewed)abstract
- Background: An important question is whether human serum levels of persistent organic pollutants has continued to decrease during the last decades. The aim of this study was to assess intra-individual variations over time of serum levels of 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153), 1,1-dichloro-2,2-bis(4-chlorophenyl)-ethene (p,p'-DDE) and hexachlorobenzene (HCB), considering the impact of a number of possible determinants. Methods: Blood samples were drawn for the same 39 subjects in 1991 and 2001. Interviews were made at both occasions. Lipid adjusted serum concentrations of CB-153, p,p'-DDE and HCB were determined in both sets of blood samples using gas chromatography-mass spectrometry. The fatty acid composition of the serum lipids was analyzed by means of gas-liquid chromatography. Result: The CB-153 concentrations in serum had averagely decreased with 34% in between 1991 and 2001 (p < 0.001). Of individual determinants only increasing BMI was associated with decreasing CB-153 levels (beta = -1.0, 95% CI -1.8, -0.2, p = 0.01), explaining 13% of the variation. The average decrease of p,p'-DDE was 55%, and could only weakly be associated with a relative increase of BMI (beta = - 1.0, 95% CI-2.3, 0.2, p=0.09), explaining only 5% of the variation. The average decrease of HCB was 53%, and was associated only with high fish consumption in 1991, explaining 12% of the variation. Conclusions: The results support a continuing decrease in human body burdens of PCBs, DDE and HCB during the 1990s. The explanatory factors relative change of BMI and fish consumption explained only a minor part of the time-related variations in serum levels.
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3. |
- Wallin, Å K, et al.
(author)
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CSF biomarkers predict a more malignant outcome in Alzheimer disease.
- 2010
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In: Neurology. - 1526-632X. ; 74:19, s. 1531-7
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Journal article (peer-reviewed)abstract
- OBJECTIVE: To investigate if patterns of CSF biomarkers (T-tau, P-tau, and Abeta42) can predict cognitive progression, outcome of cholinesterase inhibitor (ChEI) treatment, and mortality in Alzheimer disease (AD). METHODS: We included outpatients with AD (n = 151) from a prospective treatment study with ChEI. At baseline, patients underwent cognitive assessments and lumbar puncture. The patients were assessed longitudinally. The 5-year survival rate was evaluated. CSF-Abeta42, T-tau, and P-tau were analyzed at baseline. K-means cluster analysis including the 3 CSF biomarkers was carried out. RESULTS: Cluster 1 contained 87 patients with low levels of Abeta42 and relatively low levels of T-tau and P-tau. Cluster 2 contained 52 patients with low levels of Abeta42 and intermediate levels of T-tau and P-tau. Cluster 3 contained 12 patients with low levels of Abeta42 and very high levels of CSF T-tau and P-tau. There were no differences between the clusters regarding age, gender, years of education, baseline instrumental activities of daily living, or APOE genotype. Even though there was no difference between cluster 3 and the other clusters in disease duration or global rating, the patients in cluster 3 performed worse on cognitive tests already at baseline. Patients in cluster 3 exhibited a very poor outcome of ChEI treatment. Finally, cognition deteriorated faster over time and the mortality rate was substantially increased in cluster 3. CONCLUSION: A subgroup of patients with Alzheimer disease with extreme levels of CSF biomarkers exhibits worse clinical outcomes over time, including faster progression of cognitive deficits, no response to ChEI treatment, and a higher mortality.
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