Arsenic and selenium measurements in nail and hair show important relationships to Alzheimer's disease in the elderly.

BACKGROUND AND RESEARCH QUESTION: The relationships of Arsenic (As) and selenium (Se) to Alzheimer's Disease (AD) are not clearly known. This case-control observational study aims to investigate the possible relationship of these elements to the diagnosis and pathophysiology of the disease. METHODS: This case-control observational study was performed using 40 AD patients in different clinical stages and 40 healthy control subjects, living in a similar environment with low As exposure. The levels of As and Se in nail and hair were measured with Inductively Coupled Plasma Mass Spectrometry. The results were analysed with regards to clinical condition, age, disease duration, sex, education, living environment, and the relationship of the two elements using Mann Whitney U test and Spearman Rho or Pearson correlation tests as appropriate. RESULTS: The levels of As and Se were not related to age, disease duration, sex, education, or living environment in the study groups (p > 0.05). The levels of As and Se in hair and nail samples of all patients and patient subgroups were higher than those in the healthy subjects (p < 0.001). A positive correlation was found between the levels of As and Se in both hair and nail samples only in the patient group (p < 0.01). CONCLUSION: According to the results, As and Se levels probably increase due to some metabolic or genetic factors affecting both of them together. There may be an increase in the unregulated pool (selenomethionine) and a decrease in the regulated pool of Se (selenosycteine) in AD. Our findings need verification and the subject seems to deserve more elaborate evaluations including genetic analyses and analysis of different chemical forms of these elements.

Trace metal concentrations in hair and nails from Alzheimer's disease patients: Relations with clinical severity.

BACKGROUND AND OBJECTIVES: Metals, especially transition metals, seem to be important in the pathogenesis of Alzheimer disease. This study aims to determine the relationship of trace metal elements to the pathogenesis and/or course of Alzheimer Disease in terms of clinical severity. METHODS: The hair and nail trace metal levels of 62 Alzheimer Disease patients at different clinical stages (21 mild, 20 moderate, 21 severe) and 60 healthy control subjects were measured by using inductively coupled plasma-mass spectrometry. The statistical comparisons were performed with regards to the study groups, clinical stages, disease duration and age. RESULTS: The patient and control groups were significantly different from each other in regards to Mn, Fe, Cu, Cd, Hg (p<0.001), Zn (p<0.01) in nail concentrations and, Na, Al, Pb, Co (p<0.001), Fe, Mn (p=0.001), Hg, Cu, Cd, K in hair concentrations (p<0.01). No difference was detected in the levels of Mg and Ca. Nail Na level showed differences among different clinical stages of the disease (p<0.01). In comparing the mild degree Alzheimer patients to the control group; significant differences were detected in nail Mn, Fe, Cu, Co (p<0.001), Hg, Zn (p<0.01) and, hair Pb, Al (p<0.001), Na, K levels (p<0.01). CONCLUSIONS: Our results have shown that transition and posttransition metals are especially important metals for the disease process. The relation of nail Na level with clinical stages of AD is an interesting new finding, making someone to think that alkali metals may be important in the progression of the disease.

Crystal structure of 3,4a,7,7,10a-penta-methyl-3-vinyl-dodeca-hydro-1H-benzo[f]chromen-9-ol isolated from Sideritis perfoliata.

The asymmetric unit of the title compound, C20H34O2, contains two crystallographically independent mol-ecules (1 and 2) with similar conformations. In both mol-ecules, the cyclo-hexane rings adopt a chair conformation, while the oxane rings are also puckered. In the crystal, O-H⋯O hydrogen bonds connect adjacent mol-ecules, forming C(6) helical chains located around a 21 screw axis and running along the crystallographic a axis. The packing of these chains is governed only by van der Waals inter-actions. Semi-empirical PM3 quantum chemical calculations are in a satisfactory agreement with the structural results of the X-ray structure analysis. The absolute structure was indeterminate in the present experiment.

Erratum: Crystal structure of racemic [(1R,2S,3R,4S,6S)-2,6-bis-(furan-2-yl)-4-hy-droxy-4-(thio-phen-2-yl)cyclo-hexane-1,3-di-yl]bis-(thio-phen-2-yl-methanone). Corrigendum.

[This corrects the article DOI: 10.1107/S2056989016009452.].

Crystal structure of racemic [(1R,2S,3R,4S,6S)-2,6-bis-(furan-2-yl)-4-hy-droxy-4-(thio-phen-2-yl)cyclo-hexane-1,3-di-yl]bis-(thio-phen-2-yl-methanone).

In the title compound, C28H22O5S3, the central cyclo-hexane ring adopts a chair conformation. The atoms of the furan ring attached to the 6-position of the central cyclo-hexane ring are disordered over two sets of sites with occupancies of 0.832 (5) and 0.168 (5). The hy-droxy group is disordered over two positions (at the 4- and 6-positions of the cyclo-hexane ring) in the ratio 0.832 (5):0.168 (5). In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds and C-H⋯π inter-actions, forming layers parallel to (100).

Detection of free radicals in gamma-irradiated seasnail hard tissues by electron paramagnetic resonance.

Gamma-irradiated seasnail (from family of Helix lukortium) hard tissues (CaCO3) were investigated by electron paramagnetic resonance (EPR) at room temperature. The radicals produced by gamma-irradiation in seasnail were attributed to orthorhombic C*O2-, freely rotating C*O2-, orthorhombic C*O3-, axial C*O3-, and axial C*O3(3-) free radicals. Unirradiated seasnail hard tissues also feature Mn2+ ions in their EPR spectra. The hyperfine values were determined for the 13C nucleus in the orthorhombic C*O2- and axial C*O3(3-) free radicals and for the manganese impurity ions. The g values of all the free radicals have been measured. The results were compared with the literature data for similar defects.