Electron Microscopy Laboratory Research Articles

Influence of fixation on elemental composition of frozen-dried and plastic-embedded rat exocrine pancreas as revealed by XRMA: N. Roos and T. Barnard, Electron Microscopy Laboratory for Bioscience, Postbox 1062, University of Oslo, Blindern, N 0136 Oslo 3, Norway

Influence of fixation on elemental composition of frozen-dried and plastic-embedded rat exocrine pancreas as revealed by XRMA: N. Roos and T. Barnard, Electron Microscopy Laboratory for Bioscience, Postbox 1062, University of Oslo, Blindern, N 0136 Oslo 3, Norway

The use of frozen tissue for diagnostic electron microscopy

Specimens received for evaluation by a diagnostic electron microscopy laboratory do not always meet the accepted criteria for optimal preservation. Several reasons can be cited including delayed fixation, improper fixative or sample size. When a biopsy containing the diagnostic lesion is frozen at the time of surgery for an immediate diagnosis based on a cryosection or when one has a small biopsy and is not able to set aside sufficient tissue for all study parameters electron microscopy is often deleted. In our laboratory when a needle biopsy of kidney is insufficient for a complete microscopic work-up a decision may be made to freeze the tissue to provide rapid immunohistochemical data. After sufficient frozen sections are cut, the frozen tissue can then be placed in fixative for light microscopy. Because ultrastructural data sometimes would be necessary for a complete diagnosis, we have used frozen sections of renal tissue for EM studies as well.

Fine structural features in tumor diagnosis

The primary objective in submitting a specimen to the electron microscopy laboratory is to obtain additional information about the tissue which is not readily available employing conventional light microscopic techniques. In order for this analysis to be meaningful every effort must be taken to assure that the tissue is observed with minimal alteration of its structural components. Tissue which has been frozen, embedded in paraffin or placed in standard laboratory formalin will seldom exhibit the structural fidelity needed to justify the time and expense of an electron microscopic examination. While there are numerous reports on how tissues processed in this manner can, as a last resort, be retrieved for diagnostic use I suggest that the better method is to educate your staff on the proper selection and collection of specimens for possible ultrastructural evaluation.

Hazards related to EM-laboratory instrumentation.

In spite of the fact that there is a diversity of equipment in electron microscopy laboratories, potential hazards can be grouped in five areas: radiation, electricity, implosion, explosion, and cryogens. This presentation relates these areas to health hazards associated with the use and operation of various instruments and preparatory equipment typical for an EM laboratory.

Credit Due?

Credit Due? Jane A. (Halvorsen) Fagerland Jane A. (Halvorsen) Fagerland Supervisor, Electron Microscopy Laboratory Iowa State University Ames, Iowa Search for other works by this author on: Oxford Academic Google Scholar American Journal of Clinical Pathology, Volume 77, Issue 5, 1 May 1982, Page 649, https://doi.org/10.1093/ajcp/77.5.649 Published: 01 May 1982

Subplasmalemmal linear density: A mesodermal feature and a diagnostic aid

Subplasmalemmal linear density (SLD), a surface structure known to occur on mononuclear phagocytes, has been considered a possible morphologic marker of mesenchymal cells or cells of mesodermal origin. A retrospective review of human surgical pathology cases studied in a diagnostic electron microscopy laboratory over a five-year period confirmed that SLDs are primarily seen in cells of mesodermal origin in a variety of neoplastic and nonneoplastic tissues. Therefore, SLD may be of value as a mesodermal marker in evaluating poorly differentiated tumors. Furthermore, the presence or absence of SLD in tissue histiocytes in diverse conditions may contribute to the understanding of heterogeneity among this group of cells.

A rapid method for embedding tissues for electron microscopy using 1,4-dioxane and Polybed 812.

A rapid method for embedding tissues for electron microscopy is described. This method, which can be completed within 5 hr, uses 1,4-dioxane as the final dehydrating agent and Polybed 812 as the embedding medium. Satisfactory preservation of cellular structures is consistently achieved with a variety of normal and diseased tissues. This method may be of particular value to diagnostic electron microscopy laboratories where time and simplicity are critical.

An Improved Embedding Method Using ERL 4206 and Quetol 653

Journal Article An Improved Embedding Method Using ERL 4206 and Quetol 653 Get access Hiroshi KUSHIDA Hiroshi KUSHIDA Electron Microscope Laboratory of Keio University35 Shinano-machi, Shinjuku-ku, Tokyo, 160 Japan Search for other works by this author on: Oxford Academic PubMed Google Scholar Journal of Electron Microscopy, Volume 29, Issue 2, 1980, Pages 193–194, https://doi.org/10.1093/oxfordjournals.jmicro.a050228 Published: 01 January 1980 Article history Received: 21 August 1979 Published: 01 January 1980 Accepted: 21 January 1980

Improvements in Two Technics for Rapid Diagnostic Electron Microscopy

Tissue specimens can be prepared for electron microscopy in three hours instead of the usual 36. Rapid processing is made possible by using 2,2-dimethoxypropane (DMP) in place of the usual alcohol or acetone dehydration series. The technic gives excellent results and, although it was originally intended for processing diagnostic specimens only, we are now using it for all routine specimens.By applying the principle of high temperature polymerization to another procedure, we have increased the diagnostic usefulness of a technic for reprocessing hematoxylin and eosin stained, paraffin embedded tissues for EM virus identification.With these procedures we are able to make diagnoses the same day that specimens are brought to the electron microscopy laboratory.

Gingival Lesions of Pemphigus

Journal of PeriodontologyVolume 49, Issue 8 p. 428-435 Gingival Lesions of Pemphigus† Gerald Shklar, Gerald ShklarSearch for more papers by this authorSumner Frim, Sumner FrimSearch for more papers by this authorEvelyn Flynn, Evelyn FlynnSearch for more papers by this author Gerald Shklar, Gerald ShklarSearch for more papers by this authorSumner Frim, Sumner FrimSearch for more papers by this authorEvelyn Flynn, Evelyn FlynnSearch for more papers by this author First published: 01 August 1978 https://doi.org/10.1902/jop.1978.49.8.428Citations: 14 † From the Department of Oral Medicine and Oral Pathology, and the Electron Microscope Laboratory, Harvard School of Dental Medicine, 188 Longwood Dr., Boston, Mass 02115. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume49, Issue8August 1978Pages 428-435 RelatedInformation

Chronic Monocytic Leukemia

Journal Article Chronic Monocytic Leukemia Get access Claude O. Burdick, M.D., Claude O. Burdick, M.D. Departments of Pathology and Internal Medicine Valley Memorial Hospital llll E. Stanley Blvd. Livermore, California 94550 and Electron Microscopy Laboratory Veterans Administration Hospital Martinez California 94553 Search for other works by this author on: Oxford Academic Google Scholar Luis De Carvalho, Lic. Med. (Lisbon), Luis De Carvalho, Lic. Med. (Lisbon) Departments of Pathology and Internal Medicine Valley Memorial Hospital llll E. Stanley Blvd. Livermore, California 94550 and Electron Microscopy Laboratory Veterans Administration Hospital Martinez California 94553 Search for other works by this author on: Oxford Academic Google Scholar Jay Carson, M.D. Jay Carson, M.D. Departments of Pathology and Internal Medicine Valley Memorial Hospital llll E. Stanley Blvd. Livermore, California 94550 and Electron Microscopy Laboratory Veterans Administration Hospital Martinez California 94553 Search for other works by this author on: Oxford Academic Google Scholar American Journal of Clinical Pathology, Volume 69, Issue 6, 1 June 1978, Pages 648–649, https://doi.org/10.1093/ajcp/69.6.648a Published: 01 June 1978 Article history Received: 01 December 1977 Accepted: 16 January 1978 Published: 01 June 1978

A simple device to detect vibrations in the electron microscope laboratory

A simple device to detect vibrations in the electron microscope laboratory

Book Reviews

Book reviewed in this article:Electron Probe Microanalysis. By S. B. J. ReedPractical Methods in Electron Microscopy Vol. 4: Design of the Electron Microscopy Laboratory. By R. H. AldersonPractical Electron Microscopy in Materials Science, Monograph 4: Typical Electron Microscope Investigations. By J. W. EdingtonGolgi Centennial Symposium: Perspectives in Neurobiology. Ed. by M. SantiniFluorescent Protein Tracing, 4th edition. Edited by R. C. NairnThe Optical Microscope in Biology. By S. Bradbury

A New Method for Embedding with GMA and Quetol 523 for Electron Microscopic Observations on Semi-thin Sections for Light Microscopy

Journal Article A New Method for Embedding with GMA and Quetol 523 for Electron Microscopic Observations on Semi-thin Sections for Light Microscopy Get access Hiroshi KUSHIDA Hiroshi KUSHIDA Electron Microscope Laboratory of Keio UniversityShinjuku-ku, Tokyo, 160 Japan Search for other works by this author on: Oxford Academic PubMed Google Scholar Journal of Electron Microscopy, Volume 26, Issue 4, 1977, Pages 351–353, https://doi.org/10.1093/oxfordjournals.jmicro.a050085 Published: 01 January 1977 Article history Published: 01 January 1977 Received: 21 June 1977 Accepted: 29 June 1977

Sample Preparation and Measurement of Losses in Electron Optical Analyses of Particulates in Air and Water Samples

Electron optical analyses of the type and concentration of particles in air and water samples utilize some method of transferring the particulate material from the collection media to a transmission electron microscope (TEM) grid. The method used represents a significant step in sample preparation and may be the factor limiting the ultimate reliability of the data. We have found that a carbon replication technique in which the collection media (usually a membrane filter) is carbon-coated directly results in no measurable loss during the transfer. The salient features of the technique and a method for direct observation of any losses are described below.Under normal circumstances the sample received at the Electron Microscope laboratory consists of a membrane filter on which particulates have been deposited. This sample, if lightly loaded, may be prepared in the as-received condition.

Conversion of vacuum coating units for sputter coating

Sputter coating for the preparation of biological and textile materials for scanning electron microscopy appears to be superior to conventional thermal evaporation in both ease of operation and results. The commercial units for sputter coating are pumped by rotary pumps alone and are thus often inferior in the cleanliness of vacuum that can be achieved compared to the vacuum coating equipment which is standard in most electron microscopy laboratories. The present paper shows how standard type vacuum coating units can be converted for sputter coating (without detriment to other functions) at a cost which is considerably less than that of commercial sputter units.

Education and training in electron microscopy

There is currently a need for diagnostic electron microscopy in both autopsy and surgical pathology. As more information emerges from the research laboratories, applied electron microscopy will grow in depth, and all large medical centers will need the expertise provided by a diagnostic electron microscopy laboratory. Many physicians other than electron microscopists find it essential to have an understanding of the contributions and limitations of electron microscopy. Education and training programs therefore must encompass not only paramedical personnel who prepare the electron micrographs and pathologists who are thoroughly trained to interpret the electron micrographs, but also other physicians and scientists who utilize the information obtained therefrom. Medical students should obtain sufficient background in normal and abnormal ultrastructure to enable them to interpret the medical literature, and the means to obtain this background should be available within the medical school curriculum. Some medical students will also desire more thorough training obtained by elective courses in electron microscopy. Pathology residents should obtain sufficient expertise during their residency to enable them to utilize the information produced by the electron microscopy laboratory. Certain pathology residents and some pathologists in practice prefer fellowships for more specialized training in electron microscopy. Four representative training programs in electron microscopy from Veterans Administration hospitals have been selected for presentation. Each emphasizes a different approach and different objectives.

A New Type of Spray-Freezing Apparatus for Biological Materials

Journal Article A New Type of Spray-Freezing Apparatus for Biological Materials Get access Hiroyuki MORIOKA Hiroyuki MORIOKA Electron Microscopy Laboratory, Kyoto Prefectural University of MedicineKyoto Search for other works by this author on: Oxford Academic PubMed Google Scholar Journal of Electron Microscopy, Volume 24, Issue 4, 1975, Pages 307–309, https://doi.org/10.1093/oxfordjournals.jmicro.a049989 Published: 01 January 1975 Article history Published: 01 January 1975 Received: 21 July 1975

Some Biological Applications of High Voltage Electron Microscopy

The High Voltage Electron Microscope Laboratory at the University of Wisconsin has been in operation a little over one year. I would like to give a progress report about our experience with this new technique. The achievement of good resolution with thick specimens has been mainly exploited so far. A cold stage which will allow us to look at frozen specimens and a hydration stage are now being installed in our microscope. This will soon make it possible to study undehydrated specimens, a particularly exciting application of the high voltage microscope.Some of the problems studied at the Madison facility are: Structure of kinetoplast and flagella in trypanosomes (J. Paulin, U. of Georgia); growth cones of nerve fibers (R. Hannah, U. of Georgia Medical School); spiny dendrites in cerebellum of mouse (Scott and Guillery, Anatomy, U. of Wis.); spindle of baker's yeast (Joan Peterson, Madison) spindle of Haemanthus (A. Bajer, U. of Oregon, Eugene) chromosome structure (Hans Ris, U. of Wisconsin, Madison). Dr. Paulin and Dr. Hanna are reporting their work separately at this meeting and I shall therefore not discuss it here.

A New Method for Embedding with a Low Viscosity Epoxy Resin “Quetol 651”

A New Method for Embedding with a Low Viscosity Epoxy Resin “Quetol 651” Get access Hiroshi KUSHIDA Hiroshi KUSHIDA Electron Microscope Laboratory of Keio UniversityShinjuku-ku, Tokyo, Japan Search for other works by this author on: Oxford Academic PubMed Google Scholar Journal of Electron Microscopy, Volume 23, Issue 3, 1974, Page 197, https://doi.org/10.1093/oxfordjournals.jmicro.a049928 Published: 01 January 1974 Article history Published: 01 January 1974 Received: 09 July 1974