Life Sciences Commons^™

A Preliminary Study Of The Role Of Gastrointestinal Endocrine Cells In The Maintenance Of Villous Structure Following X-Irradiation, M. G. Wyatt, S. P. Hume, K. E. Carr, J. C. L. Marigold

Scanning Microscopy

The mechanism of gastrointestinal villous damage following ionizing irradiation is complex. Various compartments within the gastrointestinal tract have in turn been considered important for the maintenance of normal villous structure. To date, however, evidence for a single overriding regulator of epithelial well-being is lacking.

In this study, the role of the gastrointestinal (enteroendocrine) cells is explored and comparison made between endocrine cell number and villous structure.

Experiments were organised using hath control and irradiated groups of mice. Two time points (1 and 3 days) and three radiation doses (6, 10 and 18Gy) were employed. A simple method for endocrine cell …

Surface Characterization Of Biomaterials By Immunogold Staining - Quantitative Analysis, Kinam Park, Scott R. Simmons, Ralph M. Albrecht

Scanning Microscopy

The labeling of target proteins by immunogold particles has been analyzed based on Einstein's law of Brownian motion. The theory was confirmed from the experiments which employed antifibrinogen gold markers to label fibrinogen molecules adsorbed on the polyethylene surface. The theory predicts that the degree of labeling depends on the concentration of gold markers, temperature, medium viscosity, size of gold markers, and staining time. Of these factors most important is the concentration of immunogold particles. Small change in the marker concentration results in a significant variation in the staining efficiency when other variables are kept constant. The effect of temperature …

Nature And Properties Of Cardiovascular Deposits, B. B. Tomazic, E. S. Etz, W. E. Brown

Scanning Microscopy

Mineral deposits from human aortas and bioprosthetic devices implanted in experimental animals show close similarities in chemical composition, solubility and structural characteristics. Chemical analyses show compositions corresponding to a Na, Mg, CO₃ substituted apatitic calcium phosphate. Synergistic XRO, FT-IR and Raman Mi crop robe spectroscopic data provided coherent indication of Type-B CO₃^2- incorporation. Microscopic and electron microprobe microanalyses, however, indicate substantial morphological and spatial heterogeneity in the deposits.

Solubility and kinetic dissolution data of the mineral fraction of deposits can be compared with the corresponding data of octacalcium phosphate (OCP). This may indicate that OCP is a …

Scanning Electron Microscopy Of Microcorrosion Casts: Applications In Ophthalmologic Research, Peter C. Burger, David B. Chandler, Andrzeji W. Fryczkowski, Gordon K. Klintworth

Scanning Microscopy

In light of the complicated nature of the ocular vasculature, it has been difficult to define the normal ocular anatomy by reference to two-dimensional tissue sections. Since it provides three-dimensional replicas, scanning electron microscopy (SEM) of vascular corrosion casts has therefore been an invaluable addition to the study of ocular vasculature. This technique also often permits identification of a normal vessel's arterial, venous, or capillary nature by its surface features. In addition, this technique is finding increased use in defining anatomical features of human vascular disease and is especially well suited for the study of experimental neovascularization as it relates …

The Use Of Scanning Electron Microscopy For Identification Of Cuts And Tears In Fabrics: Observations Based Upon Criminal Cases, Muhammad Yunus Choudhry

Scanning Microscopy

Examination of fabrics to determine if they have been cut or torn may become an important issue in criminal investigations under a variety of circumstances. Since most fabrics are composed of extremely fine fibers, they present a difficult problem when such examinations are conducted by stereo light microscopy. This is particularly true when the cut fabric yarns are grossly displaced or disturbed from their original positions and where fabric edge characteristics lack the observable specificity to provide any definitive conclusion. The scanning electron microscope, due to its higher magnification, resolution and depth of field, provides an excellent technique for examination …

Scanning Electron Microscopic Observations On Differentiation And Maintenance Of Photoreceptor Cells In Vitro, R. J. Ulshafer, P. E. Spoerri, C. B. Allen, K. C. Kelley

Scanning Microscopy

Scanning electron microscopy was performed on cell cultures of embryonic and post-hatch chick retinas co-cultured with optic lobe neurons or in medium that had been pre-conditioned with optic lobe cells. The culture medium consisted of Eagles Basal Medium supplemented with glucose, fetal calf serum, glutamine and bicarbonate. Application of colchicine (Sμg/ml) to the cultures, encouraged the dissociation of retinal cell rosettes and optic lobe neuron aggregates, thereby allowing us to examine differentiation of isolated photoreceptor cells. Over time, developing photoreceptor cells gradually took on the morphological characteristics of rods and cones in the post-hatch chick: cells were polarized having a …

Assessment Of Qualitative And Quantitative Data From Pathological Hairs – A Critical Evaluation Of Scanning Electron Microscope And Proton Induced X-Ray Emission Analyses, B. Forslind, K. Wirén, K. G. Malmqvist

Scanning Microscopy

Analysis of single hair fibres in genetic disorders is a desirable complement to the clinical diagnosis. The scanning electron microscope (SEM) allows detailed study of the surface morphology of hair fibres which may explain some mechanical characteristics of the pathological hair. Quantitative elemental data may indicate biochemical or metabolic abnormalities.

In this preliminary study we assess the feasibility of combining SEM and proton induced X-ray emission (PIXE) analysis on single hair fibres from 12 cases of genetic disease influencing the integument status. We conclude that SEM is a valuable tool in the analysis of hair pathology. The macro-PIXE technique involves …

Early Scanning Electron Microscopic Studies Of Hard Tissue Resorption: Their Relation To Current Concepts Reviewed, A. Boyde, S. J. Jones

Scanning Microscopy

This paper highlights some observations made by the authors in SEM studies of hard tissue resorption and considers their significance in relation to current concepts. All mammalian mineralised tissues may undergo physiological resorption, the resulting surface reflecting the density of mineralisation and the organic matrix chemistry, organisation and orientation. Resorption-repair coupling may follow the resorption of any tissue, but SEM studies first noted this process in the case of the dental tissues. The difference between fetal and adult bone formation and resorption provided evidence against the concept of osteocytic osteolysis. SEM stereophotogrammetric methods for the quantitation of individual resorption lacunae …