A collaborative evaluation of LC-MS/MS based methods for BMAA analysis: soluble bound BMAA found to be an important fraction.

Exposure to β-Ν-methylamino-l-alanine (BMAA) might be linked to the incidence of amyotrophic lateral sclerosis, Alzheimer's disease and Parkinson's disease. Analytical chemistry plays a crucial role in determining human BMAA exposure and the associated health risk, but the performance of various analytical methods currently employed is rarely compared. A CYANOCOST initiated workshop was organized aimed at training scientists in BMAA analysis, creating mutual understanding and paving the way towards interlaboratory comparison exercises. During this workshop, we tested different methods (extraction followed by derivatization and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) analysis, or directly followed by LC-MS/MS analysis) for trueness and intermediate precision. We adapted three workup methods for the underivatized analysis of animal, brain and cyanobacterial samples. Based on recovery of the internal standard D3BMAA, the underivatized methods were accurate (mean recovery 80%) and precise (mean relative standard deviation 10%), except for the cyanobacterium Leptolyngbya. However, total BMAA concentrations in the positive controls (cycad seeds) showed higher variation (relative standard deviation 21%-32%), implying that D3BMAA was not a good indicator for the release of BMAA from bound forms. Significant losses occurred during workup for the derivatized method, resulting in low recovery ( < 10%). Most BMAA was found in a trichloroacetic acid soluble, bound form and we recommend including this fraction during analysis

Image processing method as a supporting tool for wood species identification

Examination of wood sections using microscopy is often not very satisfactory for species identifcation, and this may be the case for samples taken from objects needing restoration. This could be caused by various parameters, namely the small size of the section, condition of the section related to its age or degradation, finishes penetrating the wood material as well as sections not covering a representative area to have an objective and accurate wood identification. An image analysis method based on ImageJ, an image processing program intended for medical micrscopy, was used in this work. The method is useful for wood because it offers an objective quantitative way to separate and measure anatomical structures of the section allowing statistical analysis of the data to be carried out. This is a case study related to identifying samples from three furniture pieces needing restoration. Microslides were prepared from small samples of each furniture unit. These were observed with transmitted light microscopy. Each sample was identified by examining the microscopic images, which were interpreted for their common but also specific features and characteristics by means of ImageJ analysis and compared with reference microscopic images of known species and their characteristics provided by the literature. The species identified in this study were found to have diffuse pores. Further work should address more wood species, including softwoods, to check the usefulness of the image processing method on various situations and to understand its limitations

Wood Species for the Biedermeier Furniture - A Microscopic Characterisation for Scientific Conservation

Wood species identification is an important, compulsory step in the scientific conservation of the historic furniture as a significant part of the cultural heritage. It is known that a visual examination of an investigated sample does not always bring enough information about the original species and that a microscopic approach is more reliable. Species identification can be performed if the microscopic images are interpreted for common, but also for specific features and characteristics, by means of identification keys and in comparison with reference images. This paper provides the microscopic characterization with identification keys for six hardwood species, some of the most common in Biedermeier furniture (elm - Ulmus glabra Huds., cherry - Prunus avium L., walnut - Juglans regia L.,pear - Pyrus communis L., aspen - Populus tremula L., African mahogany - Khaya ivorensis A. Chev.). The characterization can be used for wood identification purposes by laboratories working in the field of cultural heritage wood conservation. This work is part of a recent research project that aims to develop and implement a scientific investigation for furniture conservation

Vitamin K and vascular calcifications

The role of vitamin K in the synthesis of some coagulation factors is well known. The implication of vitamin K in vascular health was demonstrated in many surveys and studies conducted over the past years on the vitamin K-dependent proteins non-involved in coagulation processes. The vitamin K-dependent matrix Gla protein is a potent inhibitor of the arterial calcification, and may become a non-invasive biochemical marker for vascular calcification. Vitamin K2 is considered to be more important for vascular system, if compared to vitamin K1 . This paper is reviewing the data from recent literature on the involvement of vitamin K and vitamin K-dependent proteins in cardiovascular health

Image Processing Method as a Supporting Tool for Wood Species Identification

Examination of wood sections using microscopy is often not very satisfactory for species identification, and this may be the case for samples taken from objects needing restoration. This could be caused by various parameters, namely small size of the section, condition of the section related to its age or degradation, finishes penetrating the wood material as well as sections not covering a representative area to have an objective and accurate wood identification. An image analysis method based on ImageJ, an image processing program intended for medical microscopy, was used in this work. The method is useful for wood because it offers an objective quantitative way to separate and measure anatomical structures of the section allowing statistical analysis of the data to be carried out. This is a case study related to identifying samples from three furniture pieces needing restoration. Microslides were prepared from small samples of each furniture unit. These were observed with transmitted light microscopy. Each sample was identified by examining the microscopic images, which were interpreted for their common but also specific features and characteristics by means of ImageJ analysis and compared with reference microscopic images of known species and their characteristics provided by the literature. The species identified in this study were found to have diffuse pores. Further work should address more wood species, including softwoods, to check the usefulness of the image processing method on various situations and to understand its limitations