CELL WALL STRUCTURE AND IRON DISTRIBUTION IN THE GREEN ALGA STAURASTRUM LUETKEMUELLERI (DESMIDIACEAE)1

The cell wall of Staurastrum luetkemuelleri Donnat & Ruttner was examined with scanning electron microscope (SEM) using whole cells, in thin sections with transmission electron microscope (TEM), and in air dried whole cells and unstained thin sections with X-ray microanalysis in the scanning-transmission electron microscope (STEM). The cell wall was ornamented with spines and wartlike structures. Spines were solid structures, consisting of deposits of cell wall material between two main cell wall layers. The wart-like structures were pore organs extending through the cell wall and the mucilaginous layer outside the cell wall. The pore cylinder was surrounded by deposits of cell wall material similar to the ones in the spines. X-ray microanalysis of selected areas on whole cells from a natural population showed iron accumulation in discrete locations on the cell extensions of S. luetkemuelleri. In the unstained thin sections iron was found only in the cell wall deposits in the spines. Cells grown in laboratory cultures failed to show iron accumulation regardless of readdition of iron-EDTA (Fe-EDTA) to the culture medium.     

Light and dissolved phosphorus interactively affect microbial metabolism,stoichiometry and decomposition of leaf litter

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The Chemistry of 2′-Deoxyribo-C-Nucleosides

Abstract

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Background

Stroke causes lasting disability and the burden of stroke is expected to increase substantially during the next decades. Optimal rehabilitation is therefore mandatory. Early supported discharge (ESD) has previously shown beneficial, but all major studies were carried out more than ten years ago. We wanted to implement and study the results of ESD in our community today with comparisons between ESD and treatment as usual, as well as between two different ESD models.

Methods

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Results

Three-hundred-and-six patients were included. mRS scores and change scores were non-significantly better in the two ESD groups at 3 and 6 months. Within-group improvement from baseline to 3 months was significant in the ESD 1 (p?=?0.042) and ESD 2 (p?=?0.001) groups, but not in the controls. More patients in the pooled ESD groups were independent at 3 (p?=?0.086) and 6 months (p?=?0.122) compared to controls and there also was a significant difference in 3 month change score between them (p?=?0.049). There were no differences between the two ESD groups. Length of stay in the stroke unit was 11 days in all groups.

Conclusions

Patients in the ESD groups tended to be more independent than controls at 3 and 6 months, but no clear statistically significant differences were found. The added effect of supported discharge and improved follow-up seems to be rather modest. The improved stroke treatment of today may necessitate larger patient samples to demonstrate additional benefit of ESD.

Clinical trial registration

Unique identifier: NCT00771771

     

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