Polarimetric optical scanning microscopy of zebrafish embryonic development using the coherency matrix

Many of the most important resolution improvements in optical microscopy techniques are based on the reduction of scattering effects. The main benefit of polarimetry-based imaging to this end is the discrimination between scattering phenomena originating from complex systems and the experimental noise. The determination of the coherency matrix elements from the experimental Mueller matrix can take advantage of scattering measurements to obtain additional information on the structural organization of a sample. We analyze the contrast mechanisms extracted from (a) the coherency matrix elements, (b) its eigenvalues and (c) the indices of polarimetric purity at different stages of zebrafish embryos, based on previous work using Mueller matrix optical scanning microscopy. We show that the use of the coherency matrix and related decompositions leads to an improvement in the imaging contrast, without requiring any complicated algebraic operations or any a priori knowledge of the sample, in contrast to standard polarimetric methods.     

Ascorbic acid and EDTA treatment of lead toxicity in rats.

Ascorbic acid given orally to lead exposed rats has similar chelating properties as equimolar amounts of parenterally administered EDTA. Ascorbic acid in combination with EDTA is more than twice as effective as either chelating agent given alone and the combination is particularly effective in removing lead from the central nervous system.     

Proteome-wide identification of NEDD8 modification sites reveals distinct proteomes for canonical and atypical NEDDylation

1. Download : Download high-res image (232KB)
2. Download : Download full-size image

     

Interactions of the eIF-4F subunits in the yeast Saccharomyces cerevisiae.

Recognition of the cap structure at the 5' end of mRNA is one of the first events in initiation of eukaryotic translation. This step is mediated by the translation initiation factor 4F (eIF-4F). In mammalian cells this factor is composed of the cap-binding protein eIF-4E, eIF-4A, and a 220-kDa polypeptide. In yeast Saccharomyces cerevisiae, eIF-4E is found associated with a 150-kDa protein (p150) and a 20-kDa protein (p20). The resulting protein complex is proposed to represent yeast eIF-4F. To study the functions of p150 and p20 and their interaction with eIF-4E, we disrupted the genes encoding p150 and p20 and analyzed the effects on protein complex formation and cell viability. Yeast cells with single and double disruptions of the genes encoding p150 and p20 are viable, but p150 single and p150/p20 double disruptions show a slow growth phenotype. Gel chromatography and immunoadsorption experiments with a monoclonal anti-eIF-4E antibody coupled to protein G-Sepharose show that both p150 and p20 bind independently of each other to eIF-4E.     

Bismuth localization within nuclear inclusions by x-ray microanalysis. Effects of accelerating voltage.

This report details the localization of bismuth by energy-dispersive x-ray microanalysis within characteristic nuclear inclusion bodies of renal tubular lining cells of rats following excessive exposure to this element. Peak to background ratios and analytical detection sensitivities for bismuth were found to vary for 04, 60 or 80 keV electron accelerating voltages. Optimum peak to background ratios were observed at 40 keV due to lower background generation, while greater detection sensitivities were recorded at 80 keV due to enhanced generation of bismuth characteristic x-rays.