In the fibroblast cell line, 3T3, lysophosphatidic acid (LPA) induces stress fiber formation. Stress fibers participate in physiological functions such as cell motility. LPA acts through a receptor coupled to a PTX-insensitive G-protein, G13. It was shown that a constitutively activated mutant of α13 (Q226L) induces stress fiber formation in Swiss3T3 cells through a second messenger cascade that involves a monomeric G-protein, Rho. The recently discovered guanine nucleotide exchange factor, p115 RhoGEF (p115) forms a link between a n and Rho A. In the presence of α13, p115 activates Rho. The N-terminus of p115 contains a regulator of G-protein signaling (RGS) box. RGS proteins act as negative regulators of G-protein dependent signaling by increasing GTPase activity and “locking” the G-protein in an inactive state. We have tested a role of p115 in the pathway coupling the LPA receptor to stress fiber formation by Rho in NTH-3T3 cells.

Taurine is transported from Purkinje cells into perineuronal glial cells during hypoosmotic swelling and is lost first from pyramidal cells during hypoxia/ ischemia, suggesting in situ cellular redistribution. Cultured isolated astrocytes or neurons and slices from rat hippocampus were treated first in 290 mOsm saline (ISO), then in 200 mOsm (HYPO) with or without taurine for 15 and 60 minutes.

Cells and slices were then fixed in 80 mM phosphate buffered (pH 7.4) fixative containing 1.25% paraformaldehyde and 2.5% glutaraldehyde followed by immuno-cytochemistry .Immunostaining was done either directly on the cell layers or on 1 micron araldite/eponate sections (Pelco). After incubation with antibody to taurine, GFAP, SNAP-25, or normal serum, immunoproduct was visualized using step-avidin-DAB (DAKO:LSAB+). Measurements of pyramidal cell diameters were made on toluidine blue-stained sections containing cells with prominent nucleoli.

The data suggest that taurine is initially lost from pyramidal cells within 15 minutes in HYPO to maintain normal cell volume, while taurine efflux from glia occurs over a 60 minute time peroid.

Tephritidae are the true fruit flies, which include the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), the walnut husk fly, Rhagoletis completa Cresson, the Mexican fruit fly, Anastrephaludens (Loew), and the apple maggot fly, Rhagoletis pomonella (Walsh). Fruit fly infestation causes major damage to many economically-important food crops and is of major concern in agriculture worldwide.

Tephritidae are controlled primarily by repeated applications of organophosphate pesticides. Health concerns, environmental pollution, and costs associated with pesticide use press researchers to find new methods for control. One approach to finding new control methods involves investigating the associations that exist between tephritids and microorganisms. Currently, bacterial odors are being used to lure these pest tephritids into traps. These flies are specifically attracted to odors from certain bacteria found to inhabit their gut. Data suggest that these bacteria are likely involved in important aspects of fruit fly nutrition and reproduction.

Basic fibroblast growth factor (bFGF) is thought to play an important role in normal tissue repair and wound healing. It is a potent mitogenic and chemotactic factor for fibroblasts. To some degree bFGF regulates proliferation and extracellular matrix (ECM) production by these cells. In this study we investigate (i) the distribution of bFGF in fibroblasts and ECM of supporting tissues (ii) the subcellular location of this protein in vivo and, (iii) mechanisms for release of this growth factor from fibroblasts.

Spurr's resin embedded ultrathin sections from adult rat sciatic nerve, adrenal gland, kidney; and from normal human lung and skin were labeled with either polyclonal (F3393-Sigma) or monoclonal antibodies (F6162-Sigma, C3316-ZymoGenetics Inc.) specific for bFGF using a two-step immunogold labeling method. Controls were incubated with either an equivalent volume of blocking solution (omitting the primary antibody) or an irrelevant antibody (Factor VIII, anti-Histamine)(Fig. 4).

C57BL/6 mice, along with other mouse genotypes, have served as models of human presbycusis. C57BL/6 mice suffer from progressively severe hearing impairments, attributable primarily to losses of both hair cells (sensory receptors) and spiral ganglion cells (afferent neurons). Their age-related hair cell degeneration in the cochlea begins in the basal turn and progresses to the apex.

Auditory nerves also undergo age-related changes. The mammalian cochlear nerve is mixed, being composed largely of afferent (sensory) fibers and a small population of efferent fibers. Because efferent nerves are primarily cholinergic, we used acetylcholinesterase (AChE) as a marker enzyme for determining both age-related changes in AChE activity of the efferent fibers and also for tracing degenerative patterns in efferent pathways within the organ of Corti.

Twelve C57BL/6 mice of the following ages were used: four young (23 days), four middle-aged (13 months), and four old (22.5 months) mice.

Alport renal disease pathogenesis is characterized by a progressive irregular thickening, thinning, and splitting of the glomerular basement membrane (GBM), which culminates in a focal and segmental glomerulonephritis and progressive loss of glomerular filtration, leading to uremia and death. A mouse model for this disease was produced using a gene targeting approach (Cosgrove et al., 1996). The resulting model displays renal pathology that is very similar to that observed in humans. As matrix accumulation has long been associated with the thickened regions of the GBM, this model provided a means to study the molecular composition and ultrastructural localization of matrix in these rarefied regions of the GBM in the Alport mouse.

We examined three matrix molecules based on preliminary data; type IV collagen α l and α2 chains, laminin-1 and fibronectin. Immunohistochemical analysis showed that while all three of these molecules localize primarily to the mesangial matrix of normal mouse glomeruli, in the Alport glomeruli these molecules seem to be heavily deposited in the GBM.

The class B ,type I scavenger receptor (SR-BI) was the first molecularly well defined cell surface receptor which binds HDL and mediates the selective uptake of HDL cholesteryl ester. It is expressed primarily in liver and steroidogenic tissues. However, the recent studies also suggested a potentially important role of SR-BI in the initial steps of cholesterol efflux in the peripheral tissues. In this study, we have used immunoblotting and immunofluorescence microscopy to study the expression and subcellular localization of SR-BI in the cultured endothelial cells and the smooth muscle cells of rat aorta.

A peptide containing residues 495 to 509 from mSR-BI plus an NH2-terminal cysteine was coupled to hemocyanin. Then the peptide was used to generate mSR-BI495 antiserum in New Zealand white rabbits. The cells from the aortic ring of 1-month-old Spraque-Dawly rats were grown in the dishes containing complete medium (Dulbecco's modified Eagle's medium with 10% fetal bovine serum) and incubated at 37°C in 95% air/ 10 % CO2 atmosphere for 3-4 days.

Each astrocyte forms an extensive network of fine processes within the surrounding neural tissue, interacting extensively with neighboring neurons and blood vessels. Fine glial processes surround synapses and probably modulate synaptic transmission. Glial endfeet on capillaries are responsible for transport of ions and metabolites and possibly control blood flow. Alterations in these fine structures may be of significance in brain function and disease. Glial fibrillary acidic protein (GFAP) is an intermediate filament found in astrocytes of the central nervous system. GFAP is commonly found in the perikarya and processes of protoplasmic and fibrous type astrocytes. Immunohistochemical labeling of GFAP is extensively used as a means of determining the location and shape of astrocytes. However, its labeling pattern varies with brain region (e.g. cortex vs. hippocampus), with cell state (natural vs. reactive astrocytes), and with the specific α- GFAP antibody used. Furthermore, Golgi-stained or dye-filled astrocytes show numerous small appendages or vellate structures that conform to the surrounding tissue and do not stain for GFAP.

Some insects cover themselves with waxy particles including all parts of their body except the eyes. Two examples of insects that produce waxy particles from specialized glands on their abdominal surfaces are the adult stages of the silverleaf whitefly (Bemisia argentifolii) and one of its predators, the dusty wing (Semidalis flinti). In both species, the production of the waxy particles begins at adult eclosion. The silverleaf whitefly, a major plant pest, produces ribbons of waxy material that extrude from the numerous microtrichia that cover the surface of abdominal wax plates. Silverleaf whitefly males have 4 pair of wax plates and females have 2 pair. The adults use their tibia to break off the extruding ribbons, forming semicircular waxy particles about 1 micrometer in diameter. The semicircular waxy particles are composed of a mixture of long-chain aldehydes and alcohols, 34 carbons in length.

For the dustywing predator, the particles are formed by wax producing pores that cover most abdominal surfaces of the adults.

Variability among hairs of humans is dependent on body source and ethnicity. Variability in the hairs of non-human mammals is also dependent on somatic source, but may exhibit a wide range of characteristics among hairs from any given site. Humans do not have secondary guard hairs as defined below, but forensic scientists involved in trace analysis must recognize a different suite of variability that exists when examining animal hairs. Hairs other than primary guard hairs from the dorsum, which are often the only representative hairs illustrated in animal hair atlases, may be present as trace evidence in a forensic case in which the origin of the hair is unknown. An overview of the different grades of animal hair that could be present in a forensic case or natural history inquiry places the secondary, tertiary, etc. guard hairs in a continuum that is based on relative diameters.

Metallurgical failure analysis is generally straight forward in many cases. However, there are times when it is difficult to really discern the fracture characteristics due to surface degradation, improper handling, or subsequent mechanical damage from improper planning.

Dr. Alan Tettleman, a founder of Failure Analysis and Associates, in San Jose, CA, once told me you can not properly conduct any product failure analysis without metallography, and especially without scanning electron microscopy. In many ways, I agree with him. There are obvious times, however, when various physical properties and deformations are apparent. Those are generally when a consultant is not required. As in your field, there are many references that assist the usage and implementation of the scanning electron microscope and energy dispersive x-ray analysis system. Many of the references introduce the procedure and some of the cautionary steps that should be taken in preparation of samples and in the interpretation of the fracture.

Probably an example of every type of material ever manipulated and utilized by man through out history will eventually find its way to a conservator for treatment and preservation. The term “art conservator”, commonly used to describe those that work to protect and preserve the physical remains of mankind's invention and creativity, is a misnomer. We are better described as conservators of cultural materials, as our work involves the preservation of a huge range of materials and artifacts, many of which would not qualify as “art” under its most accepted definition. From the sublime (a Leonardo da Vinci cartoon) to the ridiculous (a 19th century saloon singer's dress made entirely from rattlesnake skins), from the ancient (paleolithic cave paintings) to the new (a pair of Nike® Air Jordans), if they are in a collection somewhere, they are candidates for examination by a conservator.

Despite the variety of materials and artifacts facing us, professional conservators use common approaches to the care of collections and we share the same arsenal of tools.

Recent celebrated criminal cases have raised the public's awareness of forensic science. The advent of DNA technology, in particular, has led to a perception of instrumental techniques that lead to a mathematical probability of guilt that approaches certainty. Mostly passed over in press accounts of forensic operations is the use of the microscope in the examination of physical evidence. By the use of an example from an adjudicated criminal case it is hoped that a greater appreciation is gained of the microscope, that in its various forms, is by far the most widely used instrument in a crime laboratory today.

A middle-aged woman was reported missing by her son after the Memorial Day weekend in 1997. An examination of her apartment by members of the Washington State Patrol Crime Scene Response Team revealed a small amount of blood on her bedding. This bedding, together with other items, was taken into evidence.

Classical fluorphores have been widely utilized in biological research, and have been extensively modified to promote particular qualities. Here we review practical methods of optimizing fluorescence signals for microscopy, discuss experimental solutions to common laboratory applications of fluorescent probes, and describe advantages of the sulfonated rhodamines.

Fluorescence output of dyes The usefulness of a fluorescent probe depends critically on how bright it is and on its ability to resist photobleaching.

The brightness of a dye depends on two factors: first, its efficiency in capturing excitation photons, called the molar extinction coefficient, and second, on the number of photons emitted for each photon absorbed, called the quantum yield. The product of these two factors describes the brightness of a dye. Both the molar extinction coefficient and the quantum yield are constants under specific environmental conditions. Consequently, this is a measure that is useful to compare the brightness of dyes.

In many experimental situations there is some three dimensional particle that is of interest to the microscopist. To obtain morphometric information about the particle, the microscopist must section some reference space that contains the particle or component of interest, but after sectioning, the reference space and component are reduced to a 2-D sample. This sample no longer contains 3-D structures but only 2-D profiles of the reference space and component.

Stereology can be used to obtain 3-D information from 2-D samples. These samples can be micrographs or digital images, or they can even be the cut surface of the 3-D reference space. The four most basic parameters measured using stereological techniques are volume (3-D), area (2-D), length (1-D), and number (0-D). When measuring these parameters it is often advisable to first measure the density of the component within the reference space, next measure the volume of the reference space, and finally multiply the density by the reference volume to obtain the actual structural parameter.

There are many electron microscope centers around the world and it is well recognized that there is no single “right” way to develop successful research and teaching electron microscope organizations.

The model for this discussion is that of the Center for High Resolution Electron Microscopy (CHREM) at Arizona State University. Several factors, including but not limited to those discussed below, have contributed to the continuing growth and development of this Center.

The Center serves students and faculty from eight separate academic units. It is also accessible to a significant number of microscope users from outside the university. These include researchers from industry as well as other academic institutions. The number of active instrument users typically averages eighty per year. There are ten instruments available to those who successfully complete the requirements for microscope use. It is not necessary to discuss the physical plant which houses the Center's instruments. Although very important, this topic has been adequately discussed elsewhere by experienced researchers.