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PubMed1991

Immunocytochemical and ultrastructural studies of hyaline inclusions in sporadic motor neuron disease.

We investigated hyaline inclusion bodies (HI) immunocytochemically and ultrastructurally in six cases of sporadic motor neuron disease (MND). All HI contained large amounts of ubiquitin and some HI were stained at the core or the center with anti-neurofilament antibody, with the surrounding halo unstained. No HI were stained with antibodies raised against cytoskeletal proteins such as high-molecular weight microtubule-associated proteins and phosphorylated tau. Ultrastructurally, HI were chiefly composed of filaments measuring about 20 nm in diameter thicker than neurofilaments, and contained fine granules and frequently one or more of four characteristic profiles, i.e., small electron-dense materials resembling Bunina bodies, bundles of tubular filaments measuring approximately 20 nm in diameter, large electron-dense cores, and focal accumulations of randomly arranged neurofilaments. Hyaline inclusions can be regarded as one of the characteristic markers for sporadic MND as well as familial amyotrophic lateral sclerosis. Hyaline inclusions have a markedly heterogeneous ultrastructure and, therefore, differences in immunoreactivity with antineurofilament antibodies are not unexpected.

Aged↗
PubMed1990

Ultrastructural changes of liver parenchyma following digitonin-pulse perfusion of rat liver.

It has been shown that pulse perfusion of rat liver with a digitonin-containing medium results in a highly zonated hepatocyte permeabilization, allowing selective sampling of cytosolic constituents from periportal and perivenous (centrolobular) hepatocytes "in situ". In the present paper we provide an ultrastructural evaluation of the perfusion method. Identical changes in hepatocytes from affected periportal and perivenous zones are found. Affected hepatocytes appear light (electron-lucent) in electron micrographs with a sharp transition to normal hepatocytes. The most conspicuous ultrastructural findings are: (1) transformation of the sinusoidal part of the light hepatocytes, the lipocyte processes and the endothelium of affected zones apparently unifying into a continuous layer dominated by disrupted plasma membranes and 7-nm filaments; (2) deposition of osmiophilic digitonin-cholesterol complexes along the sinusoidal plasma membranes of affected zones; and (3) reduction of the cytoplasmic matrix (cytosol) in the light hepatocytes, a dilation of the mitochondrial intermembrane space with a preserved mitochondrial matrix, and a dilation of cisternae of the granular endoplasmic reticulum. The ultrastructural findings are consistent with marker-enzyme activity measured in eluates from digitonin-perfused livers, except that lysosomes appear intact, apparently contrasting with the observed eluation of amyloglucosidase (Quistorff et al. 1985).

Animals↗
PubMed1982

[Ultrastructural findings in 9 fetuses following prenatal diagnosis of neurolipidoses].

After positive prenatal enzymic diagnosis of different neurolipidoses therapeutic abortion was carried out in the 19th to 25th week of pregnancy. Ten delivered fetuses were studied ultrastructurally and in nine of them positive results were obtained, although in some cases one had to accept relatively poor structural conservation of fetal tissues. The ultrastructure of the quantitatively small lipid storage effects qualitatively resembled that of the postnatal stages with some exceptions of localization. In fetal GM2-gangliosidosis type 2 (variant 0) concentric membranous cytoplasmic bodies were detected in the brain cortex. In Krabbe's disease the myelinated regions of the spinal cord showed scattered storage (globoid) cells, sometimes closely related to blood vessels, which contained isolated or stranded tubular or spicular inclusions. In GM1-gangliosidosis type 1 neurons of the brain stem showed lamellar inclusions structured as zebra bodies, and splenic histiocytes exhibited numerous almost clear cytoplasmic vacuoles. In fetal metachromatic leukodystrophy the CNS including myelinated regions was essentially free of morphologic lipid storage effects. However, many kidney tubules cells contained great numbers of irregular or roughly parallel stacks of membranes. These inclusions may be equivalent to "tuffstone" bodies. In one fetus the bodies were restricted to tubular cells bearing microvilli. Fluorescent microscopy of arcus of the kidney tubule showed excess amounts of metachromatic material. Less of this material was demonstrable in the envelope layer of hepatic Glisson triangles. In the fetus with Niemann-Pick disease type C large neurons of the basal ganglia and the spinal cord were filled with membranous inclusions that were similar to myelin-shaped bodies rather than to solid membraneous bodies. The 19-weeks-old fetus with enzymically proven Gaucher disease was free of ultrastructural lipid storage effects. Most but not all of the morphological findings in the fetuses with neurolipidoses were in accordance with published results.

Adult↗
PubMed1995

Correlation of alterations on Na(+)-K+/Mg+2 ATPase activity, lipid peroxidation and ultrastructural findings following experimental spinal cord injury with and without intravenous methylprednisolone treatment.

The sodium-potassium activated and magnesium dependent adenosine-5'-triphosphatase (Na(+)-K+/Mg+2 ATPase EC 3.6.1.3.) activity and lipid peroxidation and early ultrastructural findings are determined in rat spinal cord at the early stage of trauma produced by a surgical clip on the thoracal 2-7 segments. The effect of treatment with intravenous methylprednisolone (MP) was evaluated the basis of these biochemical alterations and ultrastructural findings in the same model. The specific activity of the membrane bound enzyme Na(+)-K+/Mg+2 ATPase was promptly reduced in as early as ten minutes following spinal cord injury and remained at a level lower than the levels in the control group and in the sham-operated group. Methylprednisolone treatment immediately after the trauma attenuated the inactivation of Na(+)-K+/Mg+2 ATPase. On the other hand, there was significant difference in lipid peroxide content between the sham-operated and the injured animals. Methylprednisolone treatment reduced thiobarbituric acid reactive substance (TBARS) content in Group IV. We determined a positive relationship among membrane-bound enzyme Na+K+/Mg+2 ATPase activity, malondialdehyde (MDA) content and early ultrastructural changes in the traumatized and treated groups.

Animals↗
PubMed1981

Primary adenocarcinomas of the human urinary bladder: histochemical, immunological and ultrastructural studies.

Neoplastic and non-neoplastic tissue specimens from ten patients with primary adenocarcinoma of the urinary bladder were examined. Most of these tumors were associated with either foci of transitional cell carcinoma and/or with glandular metaplasia of the bladder epithelium. The mucin produced by the neoplastic cells was PAS, alcian blue, mucicarmine, PB/KOH/PAS, and RPB/KOH/PAS-positive. ABH isoantigens of these tumors were not always deleted. Ultrastructurally, the neoplastic cells resembled goblet cells. Their plasma membrane had numerous microvilli with prominent glycocalyx. Proliferation and attenuation of tight junctions were noted. The gap junctions were few and small. Two types of desmosomes were found. The ultrastructural features of the neoplastic cells were attributed in part to the malignant transformation and in part to the direction of their differentiation. We have not observed any distinctive morphologic, histochemical, immunologic or ultrastructural features that might be diagnostic for these adenocarcinomas.

Adenocarcinoma↗
PubMed1975

[The ultrastructure of fibrous and histiocytic skin tumors (dermatofibroma, dermatofibrosarcoma protuberans, fibroxanthoma, and histiocytoma) (author's transl)].

A report on the ultrastructure of the following skin tumors: dermatofibroma (7 cases), histiocytoma (4 cases), dermatofibrosarcoma protuberans (1 case), and fibroxanthoma (1 case). Because of their different ultrastructural characteristics a division into two groups is possible: one group of tumors would include dermatofibroma, dermatofibrosarcoma protuberans, and fibroxanthoma, where the formation of fibers is extensive and fibroblasts are suggested for its histogenesis. These types of tumor differ from histiocytoma, the cellular character of which is determined by a very pronounced phagocytosis and storage of lipid and hemosiderin; a histogenesis from histiocytes is probable. The nuclei of dermatofibroma and histiocytoma show a simple surfacedevelopment, whereas the nuclei of dermatofibrosarcoma protuberans and fibroxanthoma show multisegmented nuclei ("labyrinth nuclei"). In the case of dermatofibrosarcoma protuberans this kind of nuclear segmentation seems to be a morphologic correlate of its semimalignancy. Based on ultrastructural analysis a classification of these fiber-producing tumors into "fibrous histiocytomas" is not justified.

Adolescent↗
PubMed1979

Black grain mycetoma: the ultrastructure of Madurella mycetomi.

Madurella mycetomi, the fungus pathogen of black grain mycetoma, shows an elaborate development of mesosomes as its most striking ultrastructural feature. These occur in addition to mitochondria and endoplasmic reticulum. Condensations of hyphal cytoplasm and recurring intrahyphal growth of new hyphal cells are features of the pigment-producing and pathogenic phases of the organism. The abundant pigment which histochemically resembled melanin was not traceable to any ultrastructural granule, nor was it built from a tyrosine precursor. The ultrastructural changes occurring in collagen through a sclerotizing action by the fungus are briefly noted.

Catechols↗
PubMed1982

Ultrastructural pathology of human lymphocytes in lysosomal disorders: a contribution to their morphological diagnosis.

Ultrastructural examination of peripheral lymphocytes was performed in 28 cases of various lysosomal diseases, including infantile, late infantile and juvenile neuronal ceroid-lipofuscinoses (NCL), mucopolysaccharidoses (MPS), juvenile and adult metachromatic leukocystrophies (MLD), GM1-gangliosidosis, one patient with presumed mucolipidosis type IV, mucolipidosis type III, and glycogenosis type II. Based on our own observations on the ultrastructure of lymphocytes in lysosomal disorders, our results may be divided into the following 3 groups: 1. pathological findings with specific inclusions: each type of NCL, presumed mucolipidosis type IV, glycogenosis type II; 2 pathological findings with vacuoles: types I-H, II, III-A and III-B, IV, VI-A and VI-B of MPS, GM1-gangliosidosis; 3. apparently no pathological findings: juvenile and adult MLD, mucolipidosis type III, GM2-gangliosidosis, Gaucher disease. These results led us to conclude that morphological investigations utilizing lymphocytes do not always offer sufficient diagnostic information although easy accessibility favors diagnostic ultrastructural studies of lymphocytes. Such morphological studies should be supplemented by diagnostic biochemical methods.

Ceroid↗
PubMed1979

The ultrastructure of Spirulina platensis in relation to temperature and light intensity.

The ultrastructure of Spirulina platensis, a cyanobacterium with a helical morphology, has been studied in relation to temperature and light intensity. An increase in temperature gives rise to a more tightly coiled trichome, an increase in sheath material formation and a decrease in cyanophycin (above 17 degrees C) and polyglucan (above 20 degrees C) granule concentration. An increase in light intensity leads to an increase in gas vesicle concentration while the phycobilisome content decreases. Furthermore, cylindrica bodies have been observed with a somewhat different ultrastructure from those found in other species of cyanobacteria. The occurrence, size and ultrastructure of polyhedral bodies, photosynthetic lamellae, mesosomes, lipid deposits and an unknown kidney-shaped inclusion in relation to temperature and light intensity are described.

Cell Wall↗
PubMed1980

Ecophysiological studies on Spirulina platensis. Effect of temperature, light intensity and nitrate concentration on growth and ultrastructure.

The ultrastructure of the cyanobacterium Spirulina platensis was studied in relation to temperature, light intensity and nitrate concentration. The organism was able to grow in media supplied with nitrate in concentrations up to 250 mM. High nitrate concentrations increased the yield and growth rate at temperatures above 35 degeees C. Occurrence, distribution and abundance of cyanophycin granules, polyglucan granules, cylindrical bodies, carboxysomes and mesosomes varied widely in relation to the factors studied. At low temperatures (up to 17 degrees C) cyanophycin was the abundant organelle, especially at high nitrate concentrations, whereas in the temperature range 17--20 degrees C polyglucan was found in large quantities particularly at low nitrate concentrations. Special attention was paid to the cylindrical bodies, the ultrastructure of which was dependent on temperature. Three types of ultrastructure were distinguished each with several possible shapes.

Cyanobacteria↗
PubMed1985

Ultrastructure of Kaposi's sarcoma in acquired immune deficiency syndrome (AIDS).

We used electron microscopy to examine the ultrastructural morphology of Kaposi's sarcoma (KS) of the oral mucosa in patients with acquired immune deficiency syndrome (AIDS). The tumors manifested endothelial vascular proliferation and neoplastic spindle cell formations. The endothelial tumor cells contained several multivesicular bodies and a large number of tubuloreticular structures within the endoplasmic reticulum. Ultrastructural changes in the other cytoplasmic organelles included defective cell junctions that seemed to facilitate the migration and extravasation of erythrocytes through endothelial gaps, after which erythrophagocytosis occurred. Tumor cells contained viral particles which were 100-120 nm in diameter and contained dense cylindrical cores. We believe that this is the first time these particles have been identified in KS cells of the oral mucosa in patients with AIDS. These viral particles are also ultrastructurally identical to the human T-cell lymphotropic retroviruses subgroup HTLV-III. Our observations are discussed in the light of recent immunological findings.

Acquired Immunodeficiency Syndrome↗
PubMed1981

Ultrastructural changes to the cochlea resulting from impulse noise.

Following impulse noise trauma to chinchillas, observation of plastic-embedded surface preparations of the organ of Corti showed no consistent relationship between cochlear hair cell loss and permanent hearing loss (Hamernik et al. 1980). In some animals there was a loss of hearing when hair cells were present. The cochleas from that experiment were examined with transmission electron microscopy to determine at the ultrastructural level if there was damage to the sensory cells that would explain the change in threshold sensitivity. Ultrastructural changes in cochlear hair cells include an increase in lysosomes, multivesicular bodies, vacuolization of subsurface cisternae, and proliferation of Hensen bodies. These changes are observed in all experimented animals. Alterations to the ultrastructure of the stereocilia vary from animal to animal and on the outer hair cells, the changes include loosening of the stereocilia membranes, loss of stiffness, fusion of the stereocilia and disintegration of the rootlets. These changes are observed only in animals that have a permanent threshold shift after noise trauma.

Animals↗
PubMed1987

Hypophysiotrophic thyrotropin releasing hormone (TRH) synthesizing neurons. Ultrastructure, adrenergic innervation and putative transmitter action.

The neuropeptide thyrotropin releasing hormone (TRH) is capable of influencing both neuronal mechanisms in the brain and the activity of the pituitary-thyroid endocrine axis. By the use of immunocytochemical techniques, first the ultrastructural features of TRH-immunoreactive (IR) perikarya and neuronal processes were studied, and then the relationship between TRH-IR neuronal elements and dopamine-beta-hydroxylase (DBH) or phenylethanolamine-N-methyltransferase (PNMT)-IR catecholaminergic axons was analyzed in the parvocellular subnuclei of the hypothalamic paraventricular nucleus (PVN). In control animals, only TRH-IR axons were detected and some of them seemed to follow the contour of immunonegative neurons. Colchicine treatment resulted in the appearance of TRH-IR material in parvocellular neurons of the PVN. At the ultrastructural level, immunolabel was associated with rough endoplasmic reticulum, free ribosomes and neurosecretory granules. Non-labelled axons formed synaptic specializations with both dendrites and perikarya of the TRH-synthesizing neurons. TRH-IR axons located in the parvocellular units of the PVN exhibited numerous intensely labelled dense-core and fewer small electron lucent vesicles. These axons were frequently observed to terminate on parvocellular neurons, forming both bouton- and en passant-type connections. The simultaneous light microscopic localization of DBH or PNMT-IR axons and TRH-synthesizing neurons demonstrated that catecholaminergic fibers established contacts with the dendrites and cell bodies of TRH-IR neurons. Ultrastructural analysis revealed the formation of asymmetric axo-somatic and axo-dendritic synaptic specializations between PNMT-immunopositive, adrenergic axons and TRH-IR neurons in the periventricular and medial parvocellular subnuclei of the PVN. These morphological data indicate that the hypophysiotrophic, thyrotropin releasing hormone synthesizing neurons of the PVN are directly influenced by the central epinephrine system and that TRH may act as a neurotransmitter or neuromodulator upon other paraventricular neurons.

Animals↗
PubMed1982

Ultrastructural visualization of galactosyl residues in various alimentary epithelial cells with the peanut lectin-horseradish peroxidase procedure.

A conjugate of peanut lectin with horseradish peroxidase (PL-HRP) has been employed for ultrastructural localization of glycoprotein with presumed terminal galactose residues in mouse alimentary epithelial cells. The PL-HRP conjugate imparted electron opacity in sites that stain at the light microscopic level, as for example, Golgi cisternae in surface epithelial cells of the stomach and in superficial and deep crypt cells and goblet cells of the large intestine. Ultrastructural staining revealed that Golgi cisternae intermediate between the trans and cis faces stained selectively in these sites. Secretion stored in secretory granules or Golgi vesicles in the cells lacked affinity for PL-HRP conjugate, however. Selective staining of intermediate Golgi cisternae in cells with unreactive secretory product is interpreted as indicating the site of galactosyl transferase activity and a location where galactose occurs transitorily as the terminal sugar in the glycoprotein side chains. The luminal aspect of the surface epithelial cells in the stomach and columnar cells in the colon also stained, but with some variability. Staining of these surfaces was considered possibly attributable to PL affinity of some of the secretory glycoprotein which, after absorbing to the cell surface, lost terminal sialic acid through action of luminal enzyme. PL-HRP conjugate stained granules in pancreatic zymogen cells near the block surface but not in other cells, presumably because of limited penetration of reagent. Secretion on the surface of pancreatic acinar cells or in the lumen also exhibited affinity for PL-HRP complex as did the luminal surface of gastric chief cells. Staining of secretion in the pancreatic zymogen cells and gastric chief cells for galactose appeared inconsistent with lack of evidence for presence of glycoprotein in these sites which failed to stain with the periodic acid-Schiff or periodic acid-thiocarbohydrazide-silver proteinate methods for demonstrating glycoprotein at the light and electron microscopic levels. This discrepancy points to possible selective binding of PL-HRP conjugate to a moiety other than terminal galactose of glycoprotein in a few histologic sites. These results demonstrate the applicability of the PL-HRP technique at the ultrastructural level and provide information concerning the chemical structure of epithelial cell glycoproteins and their biosynthesis.

Animals↗
PubMed1986

Ultrastructural localization of extracellular immunoglobulins in immune-complex-mediated glomerulonephritis. Immunoelectron microscopy of Epon-embedded human renal biopsies using the immunogold staining procedure.

The ultrastructural localization of immunoglobulins (Igs) in immunologically mediated glomerulonephritis was achieved in ultrathin sections of glutaraldehyde-fixed, post-osmicated, Epon-embedded human renal needle biopsies using the indirect immunogold staining procedure. Extracellular Igs were identified in electron-dense deposits in subendothelial, intramembranous, subepithelial and mesangial locations in different cases of immune-complex-mediated glomerulonephritis. The excellent preservation of the ultrastructural morphology of the tissue sections made it possible to precisely correlate the presence and distribution of the antigens with those of the electron-dense deposits, which are the ultrastructural hallmarks of these diseases. Our post-embedding staining procedure which allows extracellular Igs to the accurately localized should be a very useful tool for immunomorphological investigations of glomerulonephritis.

Glomerulonephritis↗
PubMed1979

Ultrastructural demonstration of dehydrogenases in rat cerebral cortex.

Techniques for the ultrastructural demonstration of dehydrogenases in cerebral cortex are described. The best fixation for good fine structural preservation and retention of LDH and NADH-diphorase was obtained by perfusion with a misture of formaldehyde and glutaraldehyde and for SDH by perfusion with formaldehyde. Comparison of incubation conditions showed that consistent results were obtained using enzyme markers NBT and DS-NBT for LDH and NADH-diaphorase: DS-NBT was more satisfactory than NBT and BSPT for SDH. Penetration of incubation media was improved by Triton X-100: DMSO and ultrasonic treatment were less effective. The techniques enabled the first electron cytochemical demonstration of dehydrogenases in different elements of prefixed cerebral cortex. Ultrastructural sites of enzyme activities were localized within cristae and inter-membrane spaces of mitochondria in nerve cell cytoplasm and its processes, oligodendrocytes and astrocytes. Authenticity of the ultrastructural sites was confirmed by four different control experiments.

Animals↗
PubMed1990

Ciliary ultrastructure in a child with Kartagener's syndrome. A transmission electron microscopic study using tannic acid staining.

Kartagener's syndrome has been characterized by a primary ultrastructural abnormality of the cilia which consequently impairs their movements. We used transmission electron microscopy with tannic acid staining to investigate the fine structure of the cilia from the nasal mucosa of a 7-year-old girl with Kartagener's syndrome. The staining technique employed was useful for visualizing the dynein arms and protofilaments of the microtubules of the cilia. Although 15% of the cilia examined demonstrated microtubular disarrangements, these findings were considered to be acquired changes due to chronic sinusitis. No abnormal ciliary ultrastructures specific to Kartagener's syndrome, such as absence of dynein arms, were detected in this study. In such cases without any abnormal ciliary ultrastructures, it is conceivable that some other unknown factor may be involved in the impaired ciliary movement.

Actin Cytoskeleton↗
PubMed1983

The pars tuberalis of the human pituitary. A histologic, immunohistochemical, ultrastructural and immunoelectron microscopic analysis.

Forty autopsy pituitaries were studied to elucidate the histology, immunocytology and ultrastructure of pars tuberalis in subjects with normal and abnormal endocrine homeostasis. Pars tuberalis consisted mainly of gonadotrophs interspersed with few corticotrophs and thyrotrophs, histologically resembling those of pars distalis. Somatotrophs and lactotrophs were not identified. There were no histologic differences attributable to age or sex. In cases of glucocorticoid excess, pars tuberalis corticotrophs showed Crooke's hyalinization. Following castration or hypophysectomy, pars tuberalis gonadotrophs exhibited more intense immunostaining for FSH and LH than did normals. Ultrastructural analysis revealed gonadotrophs and corticotrophs showing no evidence of active secretion; immunoelectron microscopy demonstrated FSH, LH and ACTH in secretory granules. By light microscopy, squamous nests, often identified in pars tuberalis, were positive for immunoreactive keratin; cells at their periphery contained FSH, LH or ACTH, indicating derivation of nests by squamous metaplasia from gonadotrophs and corticotrophs. By electron microscopy, clusters of epithelial cells containing desmosomes and tonofilaments were surrounded by granulated gonadotrophs. Human pars tuberalis cells represent mainly a subpopulation of gonadotrophs possessing all organelles required for synthesis and storage of hormones but showing ultrastructural features of functional inactivity; the reasons for this inactivity and for the formation of squamous nests remain unexplained.

Adrenocorticotropic Hormone↗