Visualizing Fluorescence: Using a Homemade Fluorescence "Microscope" to View Latent Fingerprints on Paper.

We describe an inexpensive handheld fluorescence imager (low-magnification microscope), constructed from poly(vinyl chloride) pipe and other inexpensive components for use as a teaching tool to understand the principles of fluorescence detection. Optical filters are used to select the excitation and emission wavelengths and can be easily interchanged to accommodate different fluorescent samples. As a demonstration, we used the fluorescence imager to view lawsone-dyed fingerprints on paper, which fluoresce red when illuminated with green light.

Effect of the postictal state on visual-spatial memory in immature rats.

Postictal cognitive impairment following seizures can last from minutes to days and be disabling to the patient. The purpose of this study was to compare the behavioral features of seizures with postictal memory impairment in young seizure-naive rats and rats with a prior history of status epilepticus (SE) and examine the relationship between postictal EEG changes and cognitive recovery. Following training in the water maze to asymptote levels of learning, rats with a prior history of SE and seizure-naive rats had flurothyl-induced generalized seizures and time to recovery to baseline was then measured.

Lack of cell loss following recurrent neonatal seizures.

In the neonatal rat recurrent seizures have been associated with long-term changes in cerebral excitability and cognition. Whether recurrent seizures in the neonatal rat lead to cell loss in the cerebral cortex is not known. We counted cells in the parietal cortex, piriform cortex, and CA3 and CA1 hippocampal subfields in young adult rats that had undergone a series of 55 seizures during the first 12 days of life.