infrared imaging of the local orientation of cellulose fibrils in plant secondary cell walls.

The mechanical and chemical properties of plant cell walls greatly rely on the supramolecular assembly of cellulose fibrils. To study the local orientation of cellulose in secondary plant cell walls, diffraction limited infrared (IR) micro-spectroscopic mapping experiments were conducted at different orientation of transverse leaf section of the grass with respect to the polarization direction of the IR radiation. Two-dimensional maps, based on polarization-sensitive absorption bands of cellulose were obtained for different polarization angles.

FTIR Nanospectroscopy Shows Molecular Structures of Plant Biominerals and Cell Walls.

Plant tissues are complex composite structures of organic and inorganic components whose function relies on molecular heterogeneity at the nanometer scale. Scattering-type near-field optical microscopy (s-SNOM) in the mid-infrared (IR) region is used here to collect IR nanospectra from both fixed and native plant samples. We compared structures of chemically extracted silica bodies (phytoliths) to silicified and nonsilicified cell walls prepared as a flat block of epoxy-embedded awns of wheat (), thin sections of native epidermis cells from sorghum () comprising silica phytoliths, and isolated cells from awns of oats ().

Spectroscopic Discrimination of Sorghum Silica Phytoliths.

Grasses accumulate silicon in the form of silicic acid, which is precipitated as amorphous silica in microscopic particles termed phytoliths. These particles comprise a variety of morphologies according to the cell type in which the silica was deposited. Despite the evident morphological differences, phytolith chemistry has mostly been analysed in bulk samples, neglecting differences between the varied types formed in the same species.

Analytical profiles of "legal highs" containing cathinones available in the area of Lisbon, Portugal.

Thirteen "legal highs" were purchased in different "smart shops" in the area of Lisbon, Portugal, during the month of February 2013. The samples were analyzed by a battery of analytical methods including Fourier transform infra-red (FTIR), gas chromatography coupled with mass spectrometry (GC-MS), proton nuclear magnetic resonance ((1)H NMR) and wavelength dispersive X-ray fluorescence (WD-XRF). Active ingredients were found either as single component or in mixtures in the different products.

Urinary fibrinogen degradation products (FDP) in bladder cancer.

The value of urinary fibrinogen degradation products (EPD) as a biological marker of bladder cancer has been studied. An increase in FDP was found in 75% of bladder cancer patients, independent of the fact that they had active tumours or that they were disease free. A high correlation between the amount of the increase and the grade, local invasiveness, and risk of recurrence of the tumour has been established.