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At least 19 recordsLinked to original sources
PubMed1979

Hormonal influences on the dog prostate--a correlation study with light microscopy, transmission and scanning electron microscopy.

Dog prostates under defined hormonal influences were investigated by light microscopy (LM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The normal acinar cell apices exhibited well-developed, densely packed microvilli. TEM demonstrated numerous secretory granules, indicating a high secretory activity. Following castration, the acinar cells of the dog prostate showed rounded apices. Most of the microvilli disappeared and only knob-like protrusions were seen. Castrated dogs following administration of 3 alpha-androstandiol showed fewer microvilli than the controls; however, a well-developed undulating surface could be observed. Castrated dogs given 3 alpha-androstandiol and cyproterone acetate showed almost completely atrophic glandular cells. Prostates of dogs with spontaneous benign prostatic hyperplasia (BPH) were characterized by pleomorphism of cell shapes and surfaces. The different hormonal influences induced changes of the prostatic surface structures and secretory activity.

Androstanols↗
PubMed1979

Glomerulonephritis induced by high doses of ovalbumin. Studies by electron microscopy, immunofluorescence and immuno-electron microscopy.

Experimental glomerulonephritis was produced in 16 rabbits by intravenous injections of ovalbumin in high doses (0.1 g/day during the first week, 0.2 g x 6/day during the second). The animals were killed on day 14. At that time all animals had 2--4+ proteinuria and a serum C3 level reduced to about 50% of the control level; 11 animals had a significantly raised blood urea level. In all rabbits the antigen had induced severe proliferative glomerulonephritis. Electron microscopy showed that many of the cells accounting for the hypercellularity were monocytes. Surprisingly, electron dense deposits were few and small, mainly on the subendothelial and subepithelial aspects of the glomerular basement membrane. In all the animals ultrastructural immunoperoxidase technique revealed deposits containing ovalbumin, rabbit IgG and C3. With immunofluorescence sparse deposits were occasionally seen. It is concluded that a severe experimental glomerulonephritis can be produced in a state of antigen excess, with the deposition of immune complexes being minimal. Immuno-electron microscopy is essential, however, in detecting even the smallest animals of deposited immune reactants.

Animals↗
PubMed1977

Different types of benign nerve sheath tumors. Light microscopy, electron microscopy and autoradiography.

In a light-, electronmicroscopic and autoradiographic study different types of nerve sheath tumors were classified. Their cellular population was quantitatively evaluated in the electron microscope. In the neurinoma the predominant cell was found to be the Schwann cell, but in the different types of neurofibromata a variable content of connective tissue cells was noted. T-HE DIFFUSE NEUROFIBROMATA SHOWED A QUANTITATIVE CELLULAR COMPOSITION SIMILAR TO NORMAL PERIPHERAL NERVES. In the plexiform neurofibroma a large number of fibroblasts were present and in the argyrophilic neurofibroma high content of perineurial cells was found. In autoradiographic sections the tumors showed in general a low proliferation rate (L.i. 1-3.6%). In the argyrophilic neurofibrom a higher labelling index (9.5%) was found.

Adolescent↗
PubMed2026

Cumulative microscopy reveals cellular states in fibroblasts from patients with genetic disorders.

Analysis of cellular states and signaling trajectories can provide insights into causes of disease. We developed cumulative microscopy, a method to perform cyclical imaging without elution or quenching steps. Cumulative microscopy computationally extracts individual signals from accumulating fluorescence during sequential imaging. We use cumulative microscopy to quantitatively assess cell cycle and stress markers in individual primary fibroblasts from patients with rare genetic proliferative disorders with increased cancer risk. Neural network-based analysis of cumulative microscopy data suggests that cells from patients with Cartilage-hair hypoplasia (CHH), but not Mulibrey Nanism (MUL), show replication stress. We analyze cell states and cell trajectories and find that a subset of cells from patients with CHH show spontaneous replication stress, followed by cell cycle exit in both G1 and G2 phases. We note that replication stress potentially could underlie both proliferative defects and increased cancer risk in CHH patients and conclude that cumulative microscopy is an efficient, quantitative, and generalizable approach to multiplex microscopy.

Humans↗
PubMed1975

Localization of acetylcholinesterase in the rabbit cornea by light and electron microscopy.

Acetylcholinesterase (AChE) has been localized in the rabbit cornea by light and electron microscopy histochemical techniques. In the stroma, the enzyme is concentrated in nerves. In the epithelium, the enzyme is concentrated in intercellular spaces devoid of nerves. The morphologic appearance of the enzyme staining by light and electron microscopy in the epithelium is similar; consequently, the staining demonstrated with light microscopy examination does not always represent epithelial nerves. A significant portion of corneal acetylcholinesterase therefore appears unrelated to nerves. Considerably smaller deposits of enzyme reaction product were present in cells in every layer of the cornea, using electron microscopy histochemistry; they were not identified by light microscopy.

Acetylcholinesterase↗
PubMedDate not supplied

Microscopy of tonsillar smears and sections in tonsillar gonorrhoea.

Microscopy of methylene-blue and Gram-stained smears from the tonsillar surface and an immunofluorescence (IF) test were carried out for 130 patients, 129 with genital and/or anal gonorrhoea, 27 of whom also had tonsillar gonorrhoea. One patient had only tonsillar gonorrhoea. 5 of the 28 patients with tonsillar gonorrhoea had acute tonsillitis and for these, agreement was found between culture, light microscopy and IF test, while only 5 of the remaining 23 patients had positive microscopy. Among the 102 patients who did not have tonsillar gonorrhoea a few false-positive light microscopies and IF tests were found. Microscopy of haematoxylin-eosin stained sections of 8 tonsils from 4 patients with recurrent tonsillitis and tonsillar gonorrhoea showed subacute tonsillitis. Methylene-blue and Gram-stained sections revealed gram-negative diplococci morphologically similar to gonococci. The bacteria were located in the superficial layers of the mucous membrane (frequently intracellularly in leukocytes) and occasionally in cellular debris in the crypts.

Antibodies, Bacterial↗
PubMed1976

Simultaneous localization of proteoglycan by light and electron microscopy using toluidine blue O. A study of epiphyseal cartilage.

The simultaneous localization of proteoglycan by light and electron microscopy was demonstrated by fixing epiphyseal cartilage in a glutaraldehyde toluidine blue O solution. Sections cut for light microscopy viewing and those cut for electron microscopy required no further staining, although, in the latter case, staining with uranyl acetate and lead improved the overall contrast. By this technique, electron-dense structures were seen concentrated about the cells which were actively synthesizing matrix, and these structures appeared to bind collagen fibrils. Similar structures were not seen in conventionally fixed tissue. They could also not be identified when the specimens were previously incubated with the proteoglycan-digesting enzyme, papain, prior to toluidine blue O fixation. The toluidine blue O fixation method, unlike conventional fixation and staining, retained proteoglycan in the pericellular areas of actively synthesizing cells and made it visible by light and electron microscopy. It appears that proteoglycans is both precipitated and stained by the presence of toluidine blue O during fixation.

Animals↗
PubMed1976

Scanning electron, light, and immunofluorescent microscopy of coronaviral enteritis of turkeys (Bluecomb).

Intestinal sections from both experimental and field cases of turkey coronaviral enteritis (TCE) were examined by scanning electron microscopy and light microscopy through 10 days after inoculation and by a direct fluorescent antibody test for TCE through 12 days. Serums were collected for an indirect fluorescent antibody test for TCE through 160 days after inoculation. Lesions observed with the scanning electron microscopy were catarrhal enteritis with hemorrhage per diapedesis, epithelial desquamation, and villous atrophy which developed and regressed within 6 days after inoculation. Light microscopy demonstrated similar lesions, except that villus-to-crypt ratios remained depressed 10 days. The direct fluorescent antibody test demonstrated the presence of coronaviral antigen throughout the sampling period, and serum antibodies to TCE were present until at least 160 days, when the experiment was terminated.

Animals↗
PubMed1977

Use of electron microscopy for soil microbiology capabilities and limitations.

Soil dilutions were studied by different techniques: They were retained on cellulose filters and observed either directly by scanning electron microscopy or after inclusion and ultra-thin sectioning by transmission electron microscopy. Morphology and locomotor organs of bacteria were observed after negative staining. They were plated on various culture media in order to isolate and identify most of the nonexacting microorganisms. Results are compared and the use of electron microscopy in soil studies is discussed.

Arthrobacter↗
PubMed1979

The influence of the buffer on maintenance of tissue lipid in specimens for scanning electron microscopy.

Preparations of tissues and cells for scanning electron microscopy (SEM) fixed with glutaraldehyde (G CHO) buffered in either Na-cacodylate or Piperazine-N-N' bis (20-ethanol sulfonic acid) (PIPES) differ in their morphology. The influence of the nature of these buffers in the tissue fixing and washing solutions on appearance in scanning electron microscopy is described. Biochemical determinations of lipid retention were performed on frog and chick embryos fixed for 24 hours with 3% G CHO in either 0.03 and 0.1 M PIPES (ph. 7.3) or 0.1 M Na-cacodylate (ph. 7.3). Embryonic tissue was chosen for its relatively high lipid content and delicacy which may be expected to enhance the sensitivity at which buffer effects become apparent. The comparable small and uniform sizes of the embryos minimize differences in fixation quality due to penetration. Lipid, recovered from homogenized tissue after treatment with chloroform/methanol/water (1:2.1:1, v/v) was considered as retained. The extraction results, which showed a significant reduction of lipid losses when PIPES buffer was used, are taken to account for the morphological differences observed in SEM and transmission electron microscopy (TEM).

Animals↗
PubMed1978

[Morphological virus diagnosis--electron microscopy study of animal viruses with negative contrast procedure].

Reported in this paper are results obtained in morphological virus diagnosis by using the negative contrast technique on the basis of electron microscopy. The availability of high-efficiency electron microscopy as well as of perfectly improved techniques of preparation, knowledge of the latest virus model concepts, and indivudual skills in diagnosis are essential conditions for the above approach. Parvoviridae, picornaviridae, and togaviridae are identifiable only in high particle concentrations and by group representation. Papovaviridae, adenoviridae, herpetoviridae, poxviridae, and reoviridae, on the other hand, can be safely identified even as single particles. The diagnosis of orthomyxoviridae, paramyxoviridae, rhabdoviridae, and retroviridae is facilitated by their own dimensions and their characteristic helico-symmmetrical nucleocapside. Coronaviridae are of highly conspicuous morphology but, nevertheless, pose problems in differential diagnosis. Substantive improvement of morphological virus diagnosis, in terms of minute details, may be achieved by means of the negative contrast method on the basis of immune electron microscopy. Advantages implied in that morphological method include less time-consuming and quite uninvolved practicability and good dependability of diagnosis for more efficient decision-making in research and practice.

Animals↗
PubMed1979

Comparative scanning and transmission electron microscopy of the prostatic gland in different species (mouse, rat, dog, man).

Man, dog, rat and mouse prostatic glandular cells were compared by light microscopy (LM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). In rodents and dogs, a merocrine secretion exists, and in these species the undulating surface represented a confluence of secretory granules. The prominent secretory blebs observed in dog and human benign prostatic hyperplasia (BPH) corresponded to apocrine secretions. Also variations in the amount of secretory activity were seen. Androgenic hormones were responsible for the differentiation of the prostatic epithelial cells during development. Therefore, an absence of microvilli as well as the appearance of ruffles, microplicae, and bare cells were seen in the prepuberal and castrated rat. In the elderly rat and in human BPH, a pleomorphism of the apical cell surface was evident.

Age Factors↗
PubMed2026

Advanced High-Resolution and Super-Resolution Microscopy Techniques for Investigating Chromatin Structure and Epigenetics.

Fluorescence microscopy has emerged as an indispensable tool for investigating chromatin structure and epigenetic states. This technique not only enables super-resolution imaging to unveil detailed localizations and structures but also offers precise quantitative capabilities for comparing variations across multiple conditions. In this chapter, we present a comprehensive guide to immunofluorescence methods, detailing two primary fixation protocols. Additionally, we describe the application of super-resolution spinning disc microscopy, emphasizing its utility in detecting nuclear and epigenetic markers.

Chromatin↗
PubMed1975

Periodic acid-Schiff-light green stain to detect glomerular protein deposits by routine light microscopy.

A simple, easily reproducible periodic acid-Schiff-light green stain (PAS-LG) for the detection of glomerular protein deposits by routine light microscopy is described. The deposits are selectively stained a deep blue and contrast sharply with the staining of adjacent glomerular structures. Correlation with immunofluorescent and electron microscopy has shown that it is possible with this stain to categorize accurately a large variety of glomerular lesions by light microscopy alone.

Antigen-Antibody Complex↗
PubMed1978

Ultrastructural basis for the assay of topical acne treatments. Transmission and scanning electron microscopy of untreated comedones.

After two decades of using systemic antibiotics as a main treatment for acne, emphasis is again being placed on topical agents. Thus, it is highly desirable to have a procedure whereby the activity of the various compounds can be evaluated by direct visualization. Scanning electron microscopy combined with transmission electron microscopy provide the tools for such in assay. This study describes the ultrastructure of untreated comedones and provides the baseline or control data necessary for testing topical treatments. Comedones obtained by punch biopsies or comedo extractors were processed for electron microscopy and studied with an ETEC Autoscan Scanning Electron Microscope and with Philips EM 300 and EM 301 Transmission Electron Microscopes. Microorganisms, keratinized cells, sebum, and hairs interact with each other to form the comedonal mass. Corynebacterium acnes and Pityrosporum ovale proliferate abundantly in close association with sebum and penetrate the keratinized cells. Fine structural details of bacteria and yeasts as well as features of host-microbial relationship have been elucidated.

Acne Vulgaris↗
PubMed1979

Scanning electron microscopy of infective endocarditis.

As part of a study of the development of infective endocarditis in ncarcotic addicts, we sought to establish the feasibility of using scanning electron microscopy (SEM) to view the surface characteristics of human heart valves obtained at autopsy. Normal and infected heart valves from humans and animals were obtained at autopsy, fixed in formalin, and processed for SEM. Parallel samples from immediately adjacent regions were processed for light microscopy. Active and healed endocarditis were readily recognizable by SEM, and the observations correlated well with those made by light microscopy. The advantage of SEM in the study of endocarditis is that it provides significant information about damage to the endocardial surface across the entire valve. The relative proportions of fibrin, platelets, leukocytes, exposed stromal connective tissue and bacteria on the surface of a lesion can easily be analysed. SEM may prove particularly useful in the study of the pathogenesis of the early lesions of infective endocarditis on previously "undamaged" valves.

Animals↗
PubMed1978

Biological horizons in molecular microscopy.

The purpose envisaged in this report is not to provide a comprehensive monography but rather to give a survey, especially for biologists, of the state of the art and of current research trends in molecular microscopy. Following a brief discussion of the obvious discrepancy between instrumental capabilities and the limits of biologically significant information, a definition of the diversifying field is attempted. Four main topics are discussed. First, recent progress in the field of "low noise" specimen supports is reviewed. It is emphasized that a minimum background structure is an important but not the sole criterion for a satisfactory support. It is the ability to adsorb molecules in a predeterminable and orderly fashion which will attract wider attention in the future; positional and orientational order figure as crucial points in the strategem of low dose microscopy. Second, the problem of achieving adequate contrast without the expense of an unfaithful representation of molecular structures is discussed. Contrast is a problem of optimum imaging modes as well as of preparatory techniques. The third topic of discussion is specimen dehydration. Several avenues to circumvent or at least to alleviate dehydration artifacts are outlined. The last chapter focusses on the most fundamental problem in molecular microscopy:radiation damage. A brief synopsis of the physical and physico-chemical processes involved in damaging interactions is given and an attempt is made to tesselate the true picture of radiation damage to lipids and proteins. This might serve as a guidance in assessing the degree of structural fidelity to be expected for a given electron dose. Possibilities to overcome the radiation damage problem are adumbrated.

Desiccation↗