Ever since membranes could be resolved within cells, the pattern of intracellular membrane trafficking has been under investigation. Images made with the transmission electron microscope revealed numerous small vesicles that appeared to be shuttling between the endoplasmic rettculum (ER) and the Golgi complex. However, these static images offered no information as to the direction trie vesicles were moving and were quite inconclusive. Nevertheless, evidence built over time to suggest that unrefined proteins were moved in small vesicles from one intracellular compartment to another. Recently, a study by John Presley, Nelson Cole, Trina Schroer, Koret Hirschberg, Kristen Zaal, and Jennifer Lippincott- Schwartz with the light microscope has challenged this view. They not only presented convincing morphologic data in their published article, but they also posted some Quicktime movies on a Web site (http://dir.nichd.nih.gov/CBMB/pb1labob.html) that are even more convincing.

A question that often comes up when archiving Macintosh image files to CD-ROMs so that they can be read by either DOS or Mac computers is "What happens to the Mac resource fork of the image file?"

PC Exchange, which is built into System 7.x, creates a hidden resource fork directory on PC disks that have Mac files on them, along with additional Finder info files which contain information about file type and creator, icons, position of icons in windows, etc, Although these additional files are marked as hidden, they can be read and presumably copied by Windows '95 directly.

A scanning acoustic microscope (SAM) - a nanomicrophone using a piezoelectric crystal, may be used to examine bacterial colonies, not just materials specimens to detect phonons and listen to propagating microfractures.

Since bacterial cell walls are rigid structures, they undergo mechanical distortions when channels open and dose. This causes them to squeak and pop, each channel having its own sound. Channels and receptor molecules are all of different sizes and shapes, and therefore deform the cell wall in unique ways. This means that each channel makes a unique (if faint) sound when it passes a molecule through itself and this activity can be delected, Transport rates of uptake and excretion for the various compounds car then be calculated trom the intensity of the sounds.

Image editing sofiware is making it possible for us as microscopists to digitally prepare our micrographs for output as working prints, figures for journals, slides, inclusion in reports, or as files for transmission via the Internet or World Wide Web. In the course of becoming familiar with various sofiware applications, I decided to have some fun colorizing and recombining some scanning electron micrographs. While this kind of frivolity has no place in the presentation of scientific data, learning to manipulate images in this silly way serves two purposes; both to bring humor into the steep learning curve, and to highlight the sobering fact that you can no longer believe what you see in print. Although we would all hate to admit it, there may be unscrupulous scientists in our midst, tempted to alter visual data to suit their needs. Having said that, let me now show you one way it can be done...!

Fluorescence microscopy has proved to be an invaluable tool for biomedical science since it is possible to visualise small quantities of labeled materials (such as intracellular ions and proteins) in both fixed and living cells, However, the conventional wide field fluorescence microscope suffers from the disadvantage that objects outside the focal plane also fluoresce (in response to the excitation light) and this leads to a marked loss of contrast for objects in the focal plane, This is especially a problem when the fluorescent probe is distributed throughout the thickness of the cell and the cell is thicker than about 1 µm. The confocal microscope overcomes this problem by illuminating the preparation with a point source of excitation light and limiting the collection of light with a pinhole that is confocal with the illumination source.

In this note we show the potential usefulness of glutaraldehyde (GA) in confocai microscopic studies of wood-fungal interaction. We are presently developing methods to examine by the confocai laser scanning microscope (CLSM), the pattern of distribution of fungal hyphae within wood in relation to fungal degradation and sapstaining of wood. CLSM has the potential to be a very useful tool in such studies for a variety of reasons, including its use for optical sectioning to produce computer assisted 3-D images.

Immunohistochemical analysis was required to identity lymphoid cell subtypes in mouse appendage joint synovium tissue. Hamster and rat monoclonal antibodies directed toward lymphoid cell subtypes were found to be nonreactive in formalin-fixed decalcified appendages, and this necessitated the use of cryostat sections for immunohistochemical procedures. Initial attempts to section mouse joints using conventional cryostat techniques did not yield adequate sections, and it was clear that a different approach was necessary.