Fast Nonlinear Microscopy Reveals Impairment of Fast Axonal Transport Induced by Molecular Motor Imbalances in the Brain of Zebrafish Larvae.

Cargo transport by molecular motors along microtubules is essential for the function of eukaryotic cells, in particular neurons in which axonal transport defects constitute the early pathological features of neurodegenerative diseases. Mainly studied in motor and sensory neurons, axonal transport is still difficult to characterize in neurons of the brain in absence of appropriate tools. Here, we measured fast axonal transport by tracing the second harmonic generation (SHG) signal of potassium titanyl phosphate (KTP) nanocrystals (nanoKTP) endocytosed by brain neurons of zebrafish (Zf) larvae.

Functional analysis of cyclin-dependent kinase inhibitors of Arabidopsis.

Cyclin-dependent kinase inhibitors, such as the mammalian p27(Kip1) protein, regulate correct cell cycle progression and the integration of developmental signals with the core cell cycle machinery. These inhibitors have been described in plants, but their function remains unresolved. We have isolated seven genes from Arabidopsis that encode proteins with distant sequence homology with p27(Kip1), designated Kip-related proteins (KRPs).

[Diagnosis of a cardiac mass--a case report].

The authors describe a case of a recidivant pericardial effusion associated to a mass with an unusual, filamentous aspect that involved the upper part of right atrium and surrounded the upper vena cava. Despite the diagnostic techniques employed--transesophageal echocardiography and magnetic resonance imaging, the etiologic diagnosis could not be done, so a biopsy of the mass was made by percutaneous approach using transesophageal echocardiography to control the procedure. The histopathological result was an angiosarcoma of the right atrium.

Permeabilization of fungal membranes by plant defensins inhibits fungal growth.

We used an assay based on the uptake of SYTOX Green, an organic compound that fluoresces upon interaction with nucleic acids and penetrates cells with compromised plasma membranes, to investigate membrane permeabilization in fungi. Membrane permeabilization induced by plant defensins in Neurospora crassa was biphasic, depending on the plant defensin dose. At high defensin levels (10 to 40 microM), strong permeabilization was detected that could be strongly suppressed by cations in the medium.

Evidence that the role of plant defensins in radish defense responses is independent of salicylic acid.

Radish leaves contain two homologous 5-kDa plant defensins which accumulate systemically upon infection by fungal pathogens (F.R.G.