Life Sciences Commons^™

Scanning Electron Microscopic Studies Of The Oral Tissue Responses To Dental Implants, David E. Steflik, Ralph V. Mckinney, Allen L. Sisk, Gregory R. Parr, David L. Koth

Scanning Microscopy

Scanning electron microscopy ( SEM) and its associated technologies have proven invaluable in elucidating the interfacial oral tissue responses to dental implants. Since the dental implant must extend from the mandibular or maxillary jaw, through the oral mucosa, and into the oral cavity, these tissue responses include epithelium, connective tissue and bone. The continual occlusal forces acting upon these tissues reinforce the dynamic character of these tissue responses. Immediately upon implantation, a healing phase begins as a response to the implanted biomaterial. Following this immediate response a longer healing phase occurs, beginning approximately 1 week after implantation, resulting in the …

Kidney Structure Investigations Using Scanning Electron Microscopy Of Corrosion Casts - A State Of The Art Review, H. Ditrich, H. Splechtna

Scanning Microscopy

The corrosion casting technique using acrylic resins in the scanning electron microscope (SEM), was originally developed to investigate renal microvascular structure and is now also successfully used in studies on various other organs. However, in the last two decades nearly 100 papers have been published on the renal vascular anatomy of various taxa of vertebrates or on pathomorphological structures of kidneys, using this technique. Analyzing these works, trends and developments in this field can be summed up as follows: The majority of studies are anatomical works on the vascular system of kidneys from all vertebrate classes. In addition, experimental pathological …

Advances In Corrosion Casting Methods, K. C. Hodde, D. A. Steeber, R. M. Albrecht

Scanning Microscopy

This paper briefly discusses the concept of corrosion cast preparation (primarily of blood vessels), the use of the scanning electron microscope (SEM) to study these casts and the observations which can be made, together with the merits and the limitations in various applications. A number of reviews and surveys are quoted in which the different injection media, injection methods, animal preparations and corrosion procedures are described. A new procedure of cleaning the corrosion casts with sodium hydroxide and Triton X-100 is described. The observations which can be made are listed and illustrated both on the cellular level as well as …

Morphological Changes Of Hair Cell Stereocilia And Tectorial Membrane In Guinea Pigs With Experimentally Induced Hydrops, Sven Rydmarker, K. C. Horner

Scanning Microscopy

Endolymphatic hydrops was surgically induced in guinea pigs. Atrophy of middle and short stereocilia on the outer hair cells in the upper 13 mm of the cochlea was systematically observed by scanning electron microscopy in guinea pigs with hydrops between 5-22 months. Light microscope and scanning electron microscope observations indicated that the tectorial membrane in the apical three turns was often abnormally elevated, and could be vertically positioned in longstanding hydrops. The atrophy of outer hair cell middle and short stereocilia and the elevation of the tectorial membrane certainly contribute to the pathophysiology of experimental hydrops and might be implicated …

A Three-Dimensional Study Of The Morphology And Topography Of Pericytes In The Microvascular Bed Of Skeletal Muscle, E. Gaudio, L. Pannarale, A. Caggiati, G. Marinozzi

Scanning Microscopy

Digested tissue specimens and corrosion casts of rat soleus and tibialis anterior muscles were employed for this Scanning Electron Microscopy (SEM) study. The shape, morphology, and position of pericytes were compared to corresponding imprints on the cast surfaces. Pericytes, observed in digested tissue specimens, showed a typical morphological pattern: a central body with two primary processes that run along the capillary in opposite directions. From these primary processes, secondary ones arise and often encircle the vessel almost completely.

On the surface of corrosion casts, roundish imprints were found in the microvascular tree at the same level where digested tissue specimens …

Characterization Of Kalimashi Chromite Ore (Albania) By Scanning Electron Microscopy, Giuseppe Bonifazi, Sokol Mati

Scanning Microscopy

The textural and structural characteristics of chrome ores mined in Albania have been examined by means of scanning electron microscopy (SEM) analysis. Elemental mapping and microanalysis of Cr, Fe and Al (to identify the chromite phase) and of Mg and Si (to identify the olivine) have been carried out. A study has been made of the kind of micro-inclusions found in the ore, in order to evaluate the products of the beneficiation processes.

Textural complexity of the ore explains the difficulties involved in obtaining good recoveries and high-quality concentrates.

Dermatophyte Morphology: A Scanning Electron Microscopy Study, R. Vazquez, J. M. Riesco, A. Martin Pascual

Scanning Microscopy

The Dermatophytes are a broad group of fungi belonging to the class Fungii imperfecti that are the causative agents of dermophytosis (ringworm infections). The present work offers an overview of the morphology of these fungi found in cultures according to the scanning electron microscope. The fungi were obtained from cultures left to develop over variable periods of time that would be sufficient for growth. The morphological features of some dermatophytes obtained in artificial cultures are detailed: M. canis, M. gypseum, M. audouini, M. cookei, T. mentagrophytes, T. schoulemu, T. verrucosuin, T. ajelloi, T. prohferans, and E. floccosum. In all …

Scanning Electron Microscopy Analysis Of Polyethylene Oxide Hydrogels For Blood Contact, Sylvie Laliberté Verdon, Elliot L. Chaikof, James E. Coleman, Lori L. Hayes, Raymond J. Connolly, Karen Ramberg, Edward W. Merrill, Allan D. Callow

Scanning Microscopy

Hydrogels are a class of synthetic material, composed of a polymer-water matrix and have been proposed as tissue substitutes and drug delivery vehicles. Polyethylene oxide (PEO) hydrogels were synthesized and used to produce coated wires and conduits for baboon blood compatibility studies. Blood-material interactions were studied both by Scanning Electron Microscopy (SEM) and ¹¹¹In labeled platelet deposition.

SEM processing modifications were first evaluated in order to reduce shrinkage and surface distortion incurred during sample preparation of these high water content materials. Pretreatment with 1% tannic acid reduced bulk shrinkage associated with critical point drying by 10-20%. This effect is …

Scanning Electron Microscope Study Of Wohlfahrtia Magnifica (Schiner, 1862) (Diptera: Sarcophagidae) I. Structures With Parasitic And Possible Taxonomic Meaning, I. Ruíz-Martínez, M. D. Soler-Cruz, R. Benítez-Rodríguez, J. M. Pérez-Jiménez, C. Adalid-Fuentes, M. Díaz-López

Scanning Microscopy

The larval development of Wohlfahrtia magnifica (the most important dipteran causing sheep myiasis in the Palearctic region) has been studied by means of scanning electron microscopy. The ultrastructure of mouth-hooks, oral ridges, labial lobes, body spines and anterior and posterior peritremes is described for the first time. Their possible adaptations to a parasitic lifeway are also discussed. Thus, the use of new structures in the Sarcophagidae taxonomy is proposed from the point of view of their ultrastructure and adaptative morphology.

Comparative Analysis Of The Proliferative Response Of The Rat Urinary Bladder To Sodium Saccharin By Light And Scanning Electron Microscopy And Autoradiography, Samuel M. Cohen, Maria J. Fisher, Takao Sakata, Martin Cano, Gerald P. Schoenig, Clifford I. Chappel, Emily M. Garland

Scanning Microscopy

Three methods used to detect proliferative changes in the rat urothelium, light microscopy, scanning electron microscopy, and autoradiography, were compared for their sensitivity in detecting changes produced by administration of sodium saccharin. Weanling male F344 rats were fed sodium saccharin as 0, 3, 5, or 7.5% of the diet, and the bladders were evaluated after 4, 7, and 10 wks of feeding. Light microscopic changes and an increase in labeling index were seen at all time points in rats fed 7.5 % sodium saccharin, but not at the lower doses. A slight increase in labeling index was also observed at …

Surface Corrections To Bulk Energy Losses In Scanning Transmission Electron Microscopy Of Spheres, A. Rivacoba, P. M. Echenique

Scanning Microscopy

The interaction of a fast electron penetrating a spherical target is studied, in the frame of the classical dielectric theory. Expressions for ω the Fourier component of the induced scalar field and energy loss probability are obtained. The reduction in the bulk loss probability due to the surface boundary correction is calculated to all orders in a multipole expansion. The dependence of this correction on the impact parameter and on the radius of the sphere is also studied and compared with the results for films.

The Use Of The Scanning Electron Microscope In Investigating Container Corrosion By Canned Foods And Beverages, E. J. Helwig, H. E. Biber

Food Structure

Over the years the canned food industry has experienced corrosion problems with some foods packed in metal containers. Although most of these are minor, the net e ffect can represent significant financial loss in the industry. It is important to determine the cause of these problems, not only to assign proper responsibility but a lso to avoid recurrence of the probl em in the future. The scanning electron microscope SEM, coupled with energy dispersive x-ray microanalysis, plays an important role in these studies. Stress corrosion cracking in packs of tuna and potatoes, pitting corrosion related to light colored fruits, and …