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PubMed1979

Oral leiomyomas.

Oral leiomyomas are considered to be rare neoplasms, but they may be encountered more frequently than generally believed. Three types of leiomyomas are commonly described: solid leiomyomas, angiomyomas, and epithelioid leiomyomas. Three cases of solid leiomyoma are presented, all of which occurred in the anterior mandibular mucobuccal fold. Leiomyomas can be easily confused with other spindle-cell tumors. The necessity of using special stains, especially Mallory's phosphotungstic acid hematoxylin, is discussed.

Adult↗
PubMed1991

Morphological and ultrastructural studies of Mycoplasma flocculare and Mycoplasma hyopneumoniae in vitro.

Cells of Mycoplasma flocculare were found to vary in size and shape, especially in the later phases of growth, whereas those of Mycoplasma hyopneumoniae were fairly uniform irrespective of growth phases. Filamentous cells were present in cultures of M flocculare in the stationary and declining phases, but were never found in cultures of M hyopneumoniae. The filamentous and bizarre forms observed when mycoplasmas were suspended in phosphotungstic acid probably result from the action of the hypotonic solution. The surface of all cells was covered by a fuzzy coat consisting of fine hairs or bristles. An electron-lucent region was usually seen in cells negatively stained after centrifugation, but was only occasionally seen in cells negatively stained directly from the medium. Intracytoplasmic membranes were present in sectioned cells. No attachment organelle was found in cells of either species.

Animals↗
PubMed1975

Extracellular cross-striated banded structures in human connective tissue.

Extracellular cross-striated banded structures have been found in the connective tissues of a variety of organs. Rarely have they been found in conditions such as: hyperplastic parathyroid, follicular adenoma of the thyroid, metastatic hemangiopericytoma in the lung, sarcoidosis of lymph node, and two biopsies of nerve as reported here. The shape and size of the structure varies, as well as its periodicity, which is usually in the range of 1000 to 15000 A. An unusual exception to this general rule is the banded structure in the follicular adenoma of the thyroid where the periodicity is 270 A. These structures are quite different from native collagen or experimentally reconstituted long-space collagen, both by staining reaction with phosphotungstic acid or uranyl acetate and lead nitrate, and in their ultrastructural morphology.

Adenoma↗
PubMed1992

Cauda equina tumor with ependymal and paraganglionic differentiation.

We describe the case of a 31-year-old woman who was first treated for a pigmented choroid plexus papilloma of the fourth ventricle. Ten year later, she developed a new tumor in the region of the cauda equina. This second neoplasm contained areas of papillary ependymoma that displayed phosphotungstic acid hematoxylin-positive glial fibers and immunoreactivity for glial fibrillary acidic and S-100 proteins. Areas of ependymoma merged with others that displayed the appearance of a paraganglioma, including lobules and nests of chief cells immunoreactive for neuron-specific enolase, synaptophysin, chromogranin, and serotonin. Satellite cells, but not chief cells, stained for glial fibrillary acidic and S-100 proteins. Electron microscopy showed features of both ependymal and paraganglionic differentiation, including intercellular lumina with microvilli, junctional complexes, cell processes with closely packed filaments, and dense core granules. Our case represents a rare example of a cauda equina neoplasm with simultaneous ependymal and paraganglionic differentiation. To our knowledge, this is the first described example of a tumor of this region showing features of both ependymoma and paraganglioma.

Adult↗
PubMed1993

Sulfur-rich prostatic intraluminal crystalloids: a surgical pathologic and electron probe x-ray microanalytic study.

Prostatic intraluminal crystalloids are irregular eosinophilic, non-birefringent structures increasingly recognized as potential indicators of prostatic malignancy. In a study of 250 randomly selected surgical pathology cases of prostatic tissues none of 50 cases of benign glandular hyperplasia (0%), one of 50 cases of atypical adenomatous hyperplasia, 18 of 50 cases of well-differentiated adenocarcinoma (36%), seven of 50 cases of moderately differentiated adenocarcinoma (14%), and none of 50 cases of poorly differentiated adenocarcinoma (0%) revealed intraluminal crystalloids. A histochemical and immunohistochemical staining panel indicated that the crystalloids were nonproteinaceous. Crystalloids were stained intensely with phosphotungstic acid hematoxylin and did not stain for prostatic-specific antigen or hemoglobin. Crystalloids were clearly differentiated from prostatic corpora amylacea on light microscopy, histochemistry, scanning, and transmission electron microscopy. Electron probe x-ray microanalysis of 10 cases of crystalloids revealed uniform high sulfur peaks and small sodium peaks. We conclude that intraluminal crystalloids are associated more frequently with low-grade prostatic adenocarcinoma, may occur in benign tissue bordering adenocarcinoma, are predominantly composed of inorganic sulfur, and their presence in benign and atypical prostate biopsies may be of pathologic significance and should warrant further clinical investigation and possibly repeat biopsy.

Adenocarcinoma↗
PubMed1985

Chronic dietary choline modulates synaptic plasticity in the cerebellar glomeruli of aging mice.

A morphometric investigation was carried out on ethanolic phosphotungstic acid (E-PTA) stained synaptic junctions in the cerebellar glomeruli of adult, old, old choline-deficient and old choline-supplemented mice. Numerical (Nv) and surface (Sv) density as well as average length (L) of the synapses were calculated on 100 pictures per group. A significant reduction of Nv and Sv, as well as an increase of L was found during aging. Choline deficient animals did not show any change as compared to old animals of the same age. In choline supplemented mice Nv and Sv were significantly increased and L significantly decreased, respectively, as compared to old control littermates. No difference was found between adult and choline supplemented mice. In the cerebellar glomeruli only a small fraction of fibers are cholinergic, therefore the present findings support the idea that dietary choline can influence systems other than cholinergic. The possible role of choline supplementation in the modulation of synaptic plasticity via the synthesis and/or turnover of neuronal membrane choline phospholipids, is discussed.

Animals↗
PubMed1987

Bovine fibrinogen aggregates: electron microscopic observations of quasi-globular structures.

Electron microscopic observations of bovine fibrinogen preparations were made following negative staining with uranyl acetate and phosphotungstic acid. Preparations were first incubated at pH 6.6, gamma/2 0.3 and 0 degrees C to develop fibrinogen aggregates at concentrations approaching equilibrium levels. The fraction of fibrinogen present as aggregates, designated the product mass fraction (Pmf), was determined by gel filtration on Bio-Gel A-1.5m. Electron micrographs of preparations with significant Pmf revealed partially closed quasi-globular structures of variable size. Fibrinogen aggregates could be dissociated by incubating preparations at 2 mg/ml, 37 degrees C for 18h, with a resulting Pmf less than 0.01. In these dissociated systems, monomers were observed with no apparent aggregate forms. At intervals during the approach to equilibrium, the size distributions of aggregates present were estimated by Bio-Gel A-15m filtration. A thermodynamic analysis incorporating these and previous data led to the following model specifications. Fibrinogen aggregates develop by monomer addition, followed by periodic reactions among the constituent members of an aggregate. These intra-aggregate reactions produce a non-linear structure, most likely begin after the association of four monomers, and on the average then follow the addition of every other monomer. In this manner, quasiglobular aggregates containing up to about 28 constituent monomers may develop as equilibrium is approached.

Animals↗
PubMed1995

Expression of gamma delta T cell receptor on caprine globule leukocytes.

Histochemical characteristics and immunological surface phenotypes of globule leukocytes (GLs) of normal goats were investigated in the intestine. In the small intestine, GLs were concentrated in the base of the villus and around the crypt, whereas in the cecum and colon they were randomly distributed. Their cytoplasmic granules exclusively stained with phosphotungstic acid hematoxylin, and were negative for peroxidase and histamine in contrast to those of subepithelial mast cells. The existence of chondroitin sulfate in some granules of GLs and heparin in most granules of mast cells were revealed by alcian blue staining and digestion with chondroitinase ABC. Isolated intestinal GLs were positive for T cell receptor (TcR) 1-N24 (gamma delta) and CD8 alpha, and negative for WC1-N3 and WC1-N4. Cryostat sections of ileum revealed preferential intraepithelial distribution of both TcR1-N24+ cells and CD8+ cells. WC1-N3+ and WC1-N4+ cells were rarely seen in the epithelium and lamina propria. These results indicate that caprine GLs are a gamma delta T cell subset, which is a different cell population from WC1 positive gamma delta T cells.

Animals↗
PubMed1987

Synaptic structural changes during development and aging.

Although a great deal is known about the development of synaptic number, comparatively little is known about the effects of development, and particularly aging, on the structure of the synapse. The present study examined synaptic structure in the molecular layer of the motor-sensory neocortex during early development (postnatal days (P) 1, 3, 5, 7, 10, 15, 20, 30), adulthood (P60, 90), and old age (28 months). Tissue was stained with osmium tetroxide (osmium) or ethanol phosphotungstic acid and the following synaptic characteristics were quantified: (1) presynaptic element length, area, thickness, maximal projection height and smoothness, and number and size of vesicles adjacent to the presynaptic element; (2) postsynaptic element length, area, and thickness; and (3) cleft width. There is an early developmental increase in synaptic element length, followed by an increase in thickness into adulthood. During development the height and width of the presynaptic dense projections increase, after which they remain stable. While the number of adjacent synaptic vesicles increases throughout the lifespan, there is a parallel decrease in their size. During the period of rapid synaptogenesis in this brain region there are no decreases in any of the synaptic structural parameters examined, indicating that newly generated synapses are either formed the same size as the existing mature synapses, or are extremely plastic and grow very rapidly. Unlike age-associated changes in synaptic number, no changes were found in synaptic structure during aging.

Aging↗
PubMed1982

The effect of acute and chronic centrophenoxine treatment on the synaptic plasticity of old rats.

The cerebellar glomerulus was studied by electron microscopic morphometry in female Wistar rats. Age-dependent alterations have been revealed from 3 to 28 mth of age, and the effect of centrophenoxine (CPH) was analyzed in two different patterns of administration. First, 27-mth-old rats were treated daily for 6 wk (acute treatment), and second, 18-mth-old rats were treated 3 times per week for 5 months (chronic treatment). The dose was 100 mg CPH/kg body weight, injected intraperitoneally. The surface density (SV), the numerical density (NV) and the average length (L) of the synaptic junctions were calculated from data obtained on ethanol-phosphotungstic acid stained ultrathin sections. An age-dependent reduction of SV and NV of the synaptic contact zones was found, and the L increased in the oldest animals. CPH-treatment resulted in a marked increase of SV in both types of application, whereas the other two parameters behaved differently in the two groups. The chronic treatment resulted in a significant slowing down of the decrease of NV, whereas L remained invariate. On the contrary, the acute treatment increased L but did not alter significantly NV. The results and the differences between the treatment types are discussed in terms of synaptic plasticity and are interpreted as different manifestations of the same reactive synaptogenetic process.

Aging↗
PubMedDate not supplied

Neurobiology of the aging brain: morphological alterations at synaptic regions.

Computer-assisted morphometric studies have been carried out on nerve cell terminal regions in rats of different ages. The numerical density (Nv), the average area (S) and the surface density (Sv) of ethanol phosphotungstic acid stained (E-PTA) synaptic junctions were evaluated in cerebellar glomeruli and dentate gyrus supragranular layers. The volume density (Vv), the average volume (V) and the numerical density (Nvm) of synaptic mitochondria were measured in the cerebellar glomeruli of young (3 months), adult (11 months) and old (28 months) animals. We found that during aging Nv and Sv undergo a significant decrease, whereas S is significantly increased. The mitochondrial Vv is unchanged in all the age groups analysed, whereas in old rats V is increased and Nvm decreased, respectively. We interpret our results as supporting that the old CNS retains part of its remodelling activity and is capable of adaptive morphological response at synaptic terminal regions.

Journal Article↗
PubMed1983

Proteoglycan production by bovine granulosa cells in vitro occurs in response to fsh.

Bovine granulosa cells from small (1-9 mm) or large (10-20 mm) follicles were incubated in a chemically defined medium containing 5 muCi/ml [3H]glucosamine, gonadotropins or polypeptide hormones, 8-Br-cAMP, theophylline or trifluoperazine (TFP). Radiolabeled proteoglycans were precipitated with 10% phosphotungstic acid. Maximum incorporation of isotope occurred in 45-60 min. Radiolabeled products were completely hydrolyzed with chondroitinase ABC. FSH, but not LH or hCG, yielded a significant log-dose response. High doses of hCG inhibited the ability of granulosa to respond to FSH. No other hormone altered the FSH dose-response curve. Addition of 8-Br-cAMP or theophylline mimicked the FSH response. The FSH effect was blocked by TFP, an inhibitor of calmodulin, but cAMP or theophylline overcame the effect of TEP. No distinct difference in response to these various compounds was noted between granulosa from small or large follicles. This system provides a biochemical marker for evaluating a mechanism of action for FSH.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1982

Synaptogenesis in human visual cortex--evidence for synapse elimination during normal development.

Age-related changes in synaptic density in human visual cortical area 17 (striate cortex) were determined, based on counts in material prepared for electron microscopy with the phosphotungstic acid method. The results were correlated with measurements of the volume of striate cortex from celloidin sections. Two periods were defined, one of rapid synapse production which ends at about postnatal age 8 months, and a subsequent longer period of synapse elimination which extends past age 3 years. Exuberant synaptic connections during early childhood may impart to the immature cerebral cortex plasticity which is lost in the adult.

Adolescent↗
PubMed1988

Feline 'C'-type terminals possess synaptic sites associated with a hypolemmal cistern and Nissl body.

Previous findings suggest that axosomatic 'C'-type terminals on rat spinal motoneurones possess 'active' synaptic sites associated with the characteristic subsynaptic cistern and postsynaptic Nissl body, but 'C'-terminals in cat do not. A re-examination of feline 'C'-terminals undertook to compare the synaptic ultrastructure in aldehyde-fixed material stained by either osmium or ethanolic phosphotungstic acid (E-PTA). In agreement with previous findings osmicated cat 'C'-terminals failed to reveal synaptic complexes in regions possessing the subsynaptic cistern ('cisternal regions'). In contrast, cisternal regions of E-PTA stained 'C'-terminals exhibited a linear array of presynaptic dense projection all opposed by a single extended postsynaptic density which abutted directly onto both postsynaptic membrane and the cistern. This close topographical relationship is suggested to be functionally significant in the trans-synaptic trophism previously demonstrated for feline 'C'-terminals.

Animals↗
PubMedDate not supplied

Computer image analysis of two-dimensional crystals of beef heart NADH: ubiquinone oxidoreductase fragments. I. Comparison of crystal structures in various negative stains.

We investigated the structure of two-dimensional crystals from bovine heart mitochondrial NADH: ubiquinone oxidoreductase. A detailed description of uranyl acetate-stained crystals demonstrated that they are composed of fragments in a spatial arrangement according to space group P4212 [J. Brink, S. Hovmöller, C.I. Ragan, M.W.J. Cleeter, E.J. Boekema and E.F.J. van Bruggen, European J. Biochem. 166 (1987) 287]. To gain more structural information on the crystal structure and to assess the effects of various negative stains on the structure preservation and appearance, we examined stained crystals by means of electron microscopy and image analysis. The space group P4212 appeared to be present for several stains tested, i.e. ammonium molybdate, uranyl acetate, uranyl nitrate and uranyl sulphate. Use of phosphotungstic acid and silicotungstate resulted in a reduction of symmetry to pseudo-P4212 or p4. Use of sodium tungstate led to a considerable loss of resolution to 3.8 nm at best, whereas otherwise 1.5 to 1.9 nm could be demonstrated. The lattice vectors were not affected by the stains; they were determined as a = b = 14.9 +/- 0.25 nm with gamma = 89.8 degrees +/- 0.6 degrees. Image analysis showed the presence of similar structures with the molybdate and uranyl compounds. Differences were observed in the case of the tungstate type of stains. Furthermore, the analysis revealed the complete absence of the four small pores of 2.0 nm diameter in the unit cell. This effect was observed irrespective of the type of stain and supporting film, and could be ascribed only to the glow-discharge treatment of the supporting film. The observed difference must be caused by changed interactions between the protein, stain and supporting film. Application of correspondence analysis and clustering algorithms to the various reconstructed images of the crystals showed that they could be separated into several clusters. Each of these clusters corresponded on the average to only one type of stain, whereas a further division according to the specific uranyl compounds was observed. This study therefore shows that under identical preparation conditions subtle differences between individual stains can be detected.

Animals↗
PubMed1985

Synaptic density on the axonal tree of a pyramidal cell in the cortex of the mouse.

The aim of this study was to investigate the density and distribution of synapses on the axonal tree of a pyramidal cell in the mouse cortex. The method used was a new variation of Golgi-electron microscopy involving the modification of Colonnier, the photochemical method of Blackstad and the use of phosphotungstic acid. A segment of axon collateral of 87 microns carried 17 synapses, the proximal 27 microns being free of synapses. The main axon was postsynaptic down to a length of 30 microns. On the following 163 microns there were six presynaptic elements. On the proximal parts of four other collaterals, five synapses were found; a few synapses might, however, have been missed on these ramifications. Most of the synapses were located on thickenings already visible in the light microscope. The synaptic size varied by a factor of 2.7. The results are compared to estimates derived from former statistical investigations with other light and electron microscopical methods.

Animals↗
PubMed1989

Immunocytochemical diagnosis of early myocardial ischaemic/hypoxic damage.

The sensitive and reliable dinitrophenyl (DNP) hapten sandwich staining (DHSS) procedure (B. Jasani et al., Virchows Arch (Pathol. Anat.), 406 (1985) 441-448) was used to study the distribution of immunoperoxidase staining seen with antibodies to seven protein markers in post-mortem heart tissue. This was obtained from 12 cases with macroscopic myocardial infarction and 17 cases without myocardial infarction (10 with and 7 without significant coronary artery atherosclerosis). The immunostaining patterns were compared with the appearances seen in adjacent sections stained by the routine haematoxylin and eosin (H & E) and phosphotungstic acid haematoxylin (PTAH) methods and a method previously recommended for the detection of early myocardial infarction, the haematoxylin basic fuchsin picric acid (HBFP) stain. Loss of immunostaining with an antibody to myoglobin was found to be a reliable and more objective marker of both early and established myocardial infarction compared with the histological stains. Antibodies to myosin, caeruloplasmin, C-reactive protein and pre-albumin gave similar but less reliable results, whilst those to complement factor C3b and alpha-1 anti-trypsin gave the least reliable results for early myocardial ischaemic/hypoxic damage. The immunocytochemical results are considered sufficiently encouraging to extend the work to a large number of sudden death cases in order to establish a new, more reliable approach to the detection of histologically latent ischaemic/hypoxic damage in the myocardium.

Antigens, Surface↗
PubMed1996

Cytoskeleton immunohistochemical study of early ischemic myocardium.

Previous studies on cytoskeletal changes of in vitro and in vivo animal models of ischemic myocardium have suggested the possibility of using alterations in cytoskeleton proteins as an early marker for the post-mortem diagnosis of myocardial ischemia in cases of sudden death due to coronary artery disease (CAD). In the present study, using the technique of ABC-immunohistochemistry, we examine the changes of three cytoskeletal proteins: vinculin, desmin and alpha-actinin in human myocardial samples taken from 14 cases of CAD sudden death and 13 cases of non-CAD death. Results of these examinations are compared with immunohistochemical changes of myoglobin and histochemical staining of hematoxylin and eosin and phosphotungstic acid, and Masson trichrome. Patchy and extensive loss of the three cytoskeletal proteins was demonstrated in the myocardium of victims who died 1 h or later following the onset of symptoms of ischemic myocardium. The pattern of cytoskeleton change is equivocal in the cases of CAD who died less than 1 h after the onset of symptoms and of the cases of non-CAD. In these cases, no significant histological change was observed. With less non-specific background changes and stronger positive staining, immunohistochemical staining of the three cytoskeletal proteins is more reliable than myoglobin, which has attracted the attention of many pathologists searching for anatomic evidence of ischemic myocardium in coronary artery disease.

Adolescent↗