SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
The results of a study of 90 patients are presented. Intrapulmonary mineral deposits were characterized by electron diffraction and electron probe microanalysis. Using this method, pneumoconioses may be distinguidhed from other pneumopathies. In cases of pneumoconiosis, there exists a specific relationship between the etiology of the dust exposure and the crystallographic characteristics of the intrapulmonary deposits. The nature of the deposits may be indicative of a specific type of pneumoconiosis. This method is particularly useful in differentiating between asbestos bodies and ferruginous bodies. The value of the method in general and its importance in the study of pneumoconiosis are discussed.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Temperature controlled differentially pumped environmental chambers now allow more routine examination of wet specimens in the electron microscope. A sensitive test of their efficiency is the ability to provide high resolution electron diffraction patterns from wet, unfixed protein microcrystals. Fortunately, wet specimens can be prepared with only a few tens of nanometers thickness of remaining water, so extraneous electron scattering by liquid water can be kept to a minimum. It still remains to be determined whether microprobe analysis (X-ray or electron energy-loss spectroscopy) using wet specimens gives better element localization in cells than the current freezing methods. More extensive comparisons are also required of the ultrastructural preservation and visibility of macromolecules immersed in a thin layer of water vs immersion in a thin layer of amorphous ice. However, the recent introduction of commercial forms of the necessary equipment now make these comparisons more feasible.
Scleromyxedema (SM) may be considered as a possible disease entity in the differential diagnosis of scleroderma. Clinical data and the results of light, immunohistochemical, immunofluorescence and electron microscopic study of skin biopsies taken from a 53-year old patient with SM are reported. In the patient with SM in which abnormal serum paraprotein was not identified, the skin biopsy showed mucinous material in the dermis and proliferation of fibroblasts accompanied by mild dermal sclerosis. Immunofluorescence showed scanty granular IgG along the epidermal basement membrane and IgG and C1q focally along the connective tissue fibres in the dermis of clinically involved skin. In addition to clinical findings, detailed skin biopsy studies including contemporary techniques can contribute to the diagnosis of the disease.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
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.
A 68-year-old man with colonic polypoid ganglioneuromatosis is reported. He had manifested no signs and symptoms of von Recklinghausen's disease and/or a multiple endocrine neoplasia syndrome. A single polyp was found by a barium enema and an endoscopic polypectomy was performed. Light microscopy showed the propria mucosa of the polyp was composed of a proliferation of spindle cells with a fibrillar cytoplasma and large cells with a round large nucleus, a prominent nucleolus, and vast cytoplasm. Some crypts were slightly dilated. Random biopsied specimens from the colonic normal mucosa showed focal proliferation of only the spindle cells. Electron microscopically, the spindle cells consisted of Schwann cells forming neurites, and large cells that coincided with the features of ganglion cells. Immunohistochemically, the localization of neuron specific enolase was demonstrated in the cytoplasm of these cells. These findings led to a diagnosis of colonic polypoid ganglioneuromatosis, and the pertinent literature is reviewed.
Identification of foreign metallic substances that induce hyperpigmentation is now possible with the use of x-ray energy spectroscopy (XES), an ultrastructure, nondestructive technique that allows the correlation of the presence of foreign substances with localized tissue and cellular histological changes. This new analytic technique will be an innovative adjunctive technique in the practice of diagnostic pathology and dermatopathology. It is certain that further evaluation of hyperpigmentation will allow for better identification of possible etiological causes, especially in the evaluation of cutaneous hyperpigmentation secondary to metal toxicity.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
A consortium of microorganisms with the capacity to degrade crude oil has been characterized by means of confocal laser scanning microscopy (CLSM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The analysis using CLSM shows that Microcoleus chthonoplastes is the dominant organism in the consortium. This cyanobacterium forms long filaments that group together in bundles inside a mucopolysaccharide sheath. Scanning electron microscopy and transmission electron microscopy have allowed us to demonstrate that this cyanobacterium forms a consortium primarily with three morphotypes of the heterotrophic microorganisms found in the Microcoleus chthonoplastes sheath. The optimal growth of Microcoleus consortium was obtained in presence of light and crude oil, and under anaerobic conditions. When grown in agar plate, only one type of colony (green and filamentous) was observed.
The identification of cells in body cavities of cancer patients is sometimes difficult to make. In order to make a definite cytological diagnosis, we observed the same cells by using light microscopy (LM)-scanning electron microscopy (SEM)-transmission electron microscopy (TEM). In this study we first stained cells by the Papanicolaou method after fixation in 1% glutaraldehyde for LM, and then attempted to observe them successively by SEM-TEM after fixation in 1% paraformaldehyde and 1.25% OsO4. Our method and procedures in examining successively one and the same cells in body cavity fluids by using LM, SEM, and TEM ensured accurate discrimination among adenocarcinoma cells, mesothelial cells, and macrophages. The results of this study suggest that LM-SEM-TEM may be of diagnostic value in distinguishing among mesothelial cells, macrophages, and adenocarcinoma cells. This method also succeeded in disclosing differences between the ultrastructure of the cell surfaces, and those of the cytoplasm, and of the nuclei. It is desirable that LM-SEM-TEM observation can be introduced into various aspects in order to obtain an improvement in the diagnosis by cytologic examination, the judgment of therapeutical effects, drug selection, and prognostic presumption.