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At least 289 records · Page 16Linked to original sources
PubMed1992

Ultrastructural localization of basic lysine-rich proteins during the nucleologenesis in preimplantation bovine embryos.

The process of nucleologenesis was examined in preimplantation bovine embryos by using ethanolic phosphotungstic acid (E-PTA) at the electron microscopic level. E-PTA binds basic lysine-rich proteins and thus makes possible detection of their localization and distribution. In blastomere nuclei of 2-, 4- and early 8-cell embryos, only nucleolus precursor body/bodies (NPBs) appear, being formed from a mass which is homogeneously stained with E-PTA. In cow embryos, the whole nucleologenesis is situated in the 8-cell stage. During the following step of nucleologenesis, the NPB with a big central area (named NPB vacuole) is formed. Fibrillar mass around the central vacuole is intensively stained, especially in the regions in close vicinity to the central vacuole. Many clumps of E-PTA-positive, regularly dispersed material are found inside the vacuole. The next step of nucleologenesis is characterized by the presence of NPB with secondary vacuoles that are also filled with clumps of E-PTA-positive material. Small, intensively stained areas are visible at sites that are probably identical with those where a dense fibrillar component is formed. Until the end of the 8-cell stage, as well as in the morula and early blastocyst, typical fibrillogranular nucleoli are present. These nucleoli have 3 basic components--fibrillar centres (FC), dense fibrillar components (DFC) and granular components (GC) which stain with different increasing intensity. FC and DFC show a strong (particular) reaction while the GC are stained to a lesser degree. In all examined stages of embryonal development, the E-PTA positivity was found within the perinucleolar chromatin and on the clumps of heterochromatin. An analogical localization of basic and acidic regulatory proteins in the examined developmental stages is discussed.

Animals↗
PubMed1990

Nephrosis in two siblings with infantile sialic acid storage disease.

The diagnosis of infantile sialic acid storage disease (ISSD) was established in two siblings on the basis of typical clinical signs and the biochemical findings of hyperexcretion and intracellular storage of free sialic acid. A severe, steroid resistant nephrosis occurred in both siblings. The activities of lysosomal enzymes, including sialidase, were normal. A combined detection method for sialic acids with Limax flavus agglutinin labelling and phosphotungstic acid staining showed severely alterated sialic acid components in epithelial kidney cells and indicate a causal relationship between the nephrosis and the underlying biochemical defect. Further observations of ISSD patients with renal involvement will prove if a separate nephropathic phenotype exists.

Carbohydrate Metabolism, Inborn Errors↗
PubMedDate not supplied

Peculiar eosinophilic inclusions within astrocytes in a patient with malformed brain.

At autopsy, we observed eosinophilic inclusions within the astrocytic cytoplasm in areas of polymicrogyria and heterotopic gray matter in a 17-year-old female with severe mental retardation and physical handicaps who had died of respiratory failure. The inclusions stained with acid fuchsin, azocarmine, Holzer's stain and phosphotungstic acid hematoxylin (PTAH). They reacted with anti-S-100 protein antibody. The cytoplasm of the astrocytes containing the inclusions reacted with antibody to GFAP. The inclusions were amorphous masses that consisted of aggregated clusters of osmiophilic coarse granules about 30 nm in diameter. Some rough endoplasmic reticulum was observed on the inside and outside of the inclusions and in the cytoplasm of the astrocytes lacking such inclusions. We suggest that these inclusions resulted from an abnormality at or near the rough endoplasmic reticulum.

Adolescent↗
PubMed1992

Pathomorphologic study of pale bodies in hepatocellular carcinoma.

Pathomorphological and immunohistochemical studies were conducted on cases of hepatocellular carcinoma (HCC) with pale bodies (PB). HCC containing PBs was seen in 6 (5.7%) of 106 consecutively resected HCC cases. It was of interest that varying degrees of sclerotic change were found in 4 of the 6 cases and a certain correlation between PBs and sclerotic change of HCC tissue was suggested. Histologically, PBs were identified as a pale amorphous substance with a distinct margin and most of PBs occupied the entire cytoplasm of the cancer cells. PBs were practically negative for periodic-acid Schiff, and were also negative for phosphotungstic acid hematoxylin and orcein stains. Ultrastructurally, PBs were found to be a mass of granular or fibrillar materials having a single-layered limiting membrane, and dilated rough endoplasmic reticular (rER) were also found in the vicinity of PBs, suggesting the presence of a close relationship between rough endoplasmic reticula and PBs. Most PBs were found to be strongly positive for anti-fibrinogen antibody and some of them were weakly positive for anti-albumin, but were solely negative for other antibodies such as anti-HBs antigen, anti-alpha-1-antitrypsin, and anti-ferritin. According to those findings, PBs were thought to be fibrinogens accumulating in cystic rER due to a defective intracellular transport or an excretion disturbance.

Aged↗
PubMed1986

Eosinophilic globules in Kaposi's sarcoma. A histochemical, immunohistochemical, and ultrastructural study.

Of the 12 cases, 2 (17%) showed eosinophilic globules in the typical cutaneous type of Kaposi's sarcoma. The globules were stained with periodic acid-Schiff (PAS), periodic acid-Schiff reagent after diastase digestion, and phosphotungstic acid hematoxylin (PTAH), but were not stained with Mayer's mucicarmine, and alcian blue. As the results, these globules might be glycoprotein. The shape of the globules was very similar to glycoprotein globules of yolk sac tumor (endodermal sinus tumor) in the tissue of the ovary and testis. In the yolk sac tumor, similar globules are stained with alpha-fetoprotein, beta-subunit of human chorionic gonadotropin, and alpha-1-antitrypsin using immunohistochemical techniques. Immunoperoxidase investigations were done with antibodies to alpha-fetoprotein, beta-subunit of human chorionic gonadotropin, alpha-1-antitrypsin, and carcinoembryonic antigen in the eosinophilic globules of Kaposi's sarcoma, but these antigens were detected in the globules. The morphogenesis of the glycoprotein globules is not clear yet. A better understanding of the source of globules in Kaposi's sarcoma awaits further research.

Carcinoembryonic Antigen↗
PubMed1973

Ultrastructural alterations associated with the growth of resistant Pseudomonas aeruginosa in the presence of benzalkonium chloride.

Cells of Pseudomonas aeruginosa resistant to benzalkonium chloride (BC) underwent unique ultrastructural reorganizations when they were grown in the presence of 1 mg of BC/ml. The resistant cells usually contained a single, centrally positioned pseudovacuole. The pseudovacuole was surrounded by a diffuse substance that spread irregularly throughout the cytoplasm. The presence of the pseudovacuole seemed to cause a physical compartmentalization of the cytoplasm into random pockets of ribosomes and nuclear material. Contained within the pseudovacuole was a horseshoe-shaped, electron-dense body which was bounded by a trilaminar membrane 5.2 nm in width. These bodies averaged 77 nm when measured through the long axis. The surfaces of resistant cells were covered by an additional layer not found in sensitive cells. Thin sections of sensitive cells which had been treated with 1 mg of BC/ml showed little or no lysis. The cytoplasm appeared to be deeply stained and coagulated. Ribosomes were no longer distinctly visible. Although the cell wall remained intact, the cell membrane was dissolved and fragmented. BC-grown resistant cells could not be successfully stained by standard techniques; however, details were demonstrated with the aid of a combination of 1.5% glutaraldehyde, 1% osmium tetroxide, and 1% phosphotungstic acid prepared in 0.1 m sodium dimethylarsonate buffer (pH 6.8).

Benzalkonium Compounds↗
PubMed1984

Determination of LDL cholesterol and LDL apolipoprotein B following precipitation of VLDL in blood serum with phosphotungstic acid/MgCl2.

A method is described for the selective precipitation of VLDL in blood serum using phosphotungstic acid/MgCl2. The method allows for the calculation of LDL apolipoprotein B as well as for the calculation of LDL cholesterol (following the additional determination of HDL cholesterol). Dependent on the triglyceride and the cholesterol content of the serum, three different procedures were developed using phosphotungstic acid and MgCl2 in different concentrations in the precipitation assay. Within the tested range of 3-10 mmol/l total cholesterol and 1-4 mmol/l triglyceride in blood serum the VLDL were nearly completely precipitated with negligible coprecipitation of LDL and HDL, but 40-50% coprecipitation of Lp(a). Regression analysis of the cholesterol values obtained by precipitation with phosphotungstic acid/MgCl2 (= serum cholesterol - LDL cholesterol), and the cholesterol values obtained by ultracentrifugation (d greater than 1.006 kg/l) revealed a good measure of agreement (r = 0.97, y = 0.93 X + 0.35, n = 76). An equally good measure of agreement was found for the corresponding apolipoprotein B values (r = 0.96, y = 1.03 X - 0.2, n = 61). In the determination of LDL cholesterol a variation coefficient of 4.3% (n = 20) was found in relation to the precision in the series, and a variation coefficient of 4.8% (n = 25) in relation to day to day precision.

Apolipoproteins↗
PubMed1988

Structural aspects, potassium stimulation and calcium dependence of nonsynaptic neuropeptide release by the egg laying controlling caudodorsal cells of Lymnaea stagnalis.

The cerebral peptidergic caudodorsal cells of the freshwater snail Lymnaea stagnalis control egg laying and egg-laying behaviour by releasing peptides into (1) the haemolymph, from neurohaemal axon terminals in the periphery of the cerebral commissure and (2) the intercellular space of the central nervous system, from collaterals in the inner compartment of this commissure. Recently, it was shown that collateral release occurs from nonsynaptic release sites, which lack the morphological specializations that are characteristic of classical synapses. Probably, these sites enable the caudodorsal cells to communicate with central neurons in a nonsynaptic ("paracrine", "diffuse", "hormone-like") fashion. The structural and ionic bases of nonsynaptic release were studied using the tannic acid-Ringer incubation-method for the detection of exocytotic release of secretory granule contents in vitro. Elevation of the extracellular potassium concentration strongly stimulates exocytotic activity in the collaterals. No stimulation was found in the absence of extracellular calcium ions. Similar results have been obtained for the neurohaemal axon terminals. Electron-dense material occurs apposed at the cytoplasmic side of the axolemma of collaterals (ethanolic phosphotungstic acid method). This material appears homologous with the presynaptic dense projections forming the "vesicular grid" in classical synapses. Such projections are also present in the neurohaemal axon terminals. It is concluded that secretion from nonsynaptic release sites in caudodorsal cell collaterals shares fundamental characteristics with secretion from conventional neuronal release sites (neurohaemal axon terminals and classical synapses); release occurs by exocytosis of secretory granules, is associated with a vesicular grid, is stimulated by membrane depolarization, and depends on the presence of extracellular calcium ions.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1980

[Determination of the high density lipoprotein (HDL) cholesterol in blood serum. Comparison of 3 methods: ultracentrifugation and precipitations (author's transl)].

Three methods of assaying the high density lipoprotein cholesterol were applied simultaneously to a hundred of human sera: ultracentrifugation, precipitation by concavalin A and phosphotungstic acid. The obtained results were compared by statistical means: it was shown that the three procedures were equivalent. Some of their analytical features are discussed.

Chemical Precipitation↗
PubMed1978

Influence of beta-amino-propionitrile on elastogenesis in the chick embryo (light and electron microscopic study).

Beta-amino-propionitrile was administered in a single dose into the chorioallantoic cavity of 14 days old chick embryos. The effects on the elastic fibre production were examined on the 3rd or 7th day following the injection. By light microscopy dissecting aneurysm, aortic ruptures were found. The elastic fibres were poorly developed and exhibited irregularities and structural anomalies. Electron microscopically we observed reduction of the number or complete absence of elastic aggregates and fibres. The elastic structures exhibited abnormal phosphotungstic acid binding. This was considered as a sign for disturbances in the development of cross linkages and in the incorporation of elastin into the elastic fibres.

Aminopropionitrile↗
PubMed1999

Growth of collagen fibrils produced by human osteosarcoma cells: high-resolution scanning electron microscopy.

To demonstrate three-dimensionally the process of the collagen fibril growth, the bottom of culture dishes with human osteosarcoma cells (NOS-1) and their extracts were examined by conventional scanning electron microscopy (SEM). Backscattered electron (BSE) imaging of SEM was also applied to the specimens, which were stained with phosphotungustic acid and uranyl acetate. Conventional SEM images showed several stages of collagen fibril assembly. Short collagen fibrils with tapered ends were distributed at the bottom of the dish just beneath and/or around the cultured cells; they were 1 microm long and 20-30 nm in diameter at the thickest middle portion. These fibrils were often twisted and united in a right helical direction, and consequently increased in length (5-10 microm) and diameter (more than 100 nm). In BSE images, the periodical bands stained with phosphotungstic acid and uranyl acetate were visualized throughout the individual fibrils. The banding pattern indicated that the polarity of the collagen molecules was unidirectional; namely, that all molecules were pointed in the same direction throughout the length of the fibrils.

Biopolymers↗
PubMed1966

Cytochemistry of synapses: selective staining for electron microscopy.

Material at synapses and in some synaptic vesicles becomes selectively stained when glutaraldehyde-fixed rat brain that has not been treated with osmium is stained with phosphotungstic acid. The material stained at synapses is distinct from the adjacent unstained synaptic membranes and has cytochemical properties of protein. The specialized spatial arrangement exhibited by this synaptic material suggests its close involvement in synaptic function.

Aldehydes↗
PubMed1973

Ultrastructural study of crossbands occurring in the stalks of Caulobacter crescentus.

An ultrastructural study of crossbands isolated from Caulobacter crescentus Sk1 418 stalks permitted a view of these structures in a plane other than the perpendicular view normally presented in the electron microscope. These crossbands were composed of concentrically arranged, alternating light and dark bands when stained with phosphotungstic acid. Evidence supports the hypothesis that crossbands appear to compose a structural barrier extending the width of the stalk and may function to support unit membrane extending the length of the stalk.

Bacteria↗
PubMed1984

[A new method for the demonstration of the Bordetella bronchiseptica capsule in electron microscopy].

A new and rapid working method is presented for electronmicroscopic preparation of capsules from gram negative bacteria, e.g. Bordetella bronchiseptica and Pasteurella multocida. The advantage of the new technique is the availability of the results within 30 min after starting the preparation. The staining of the capsule by alcian blue has to be done as a first step together with glutaraldehyde fixation, before staining the bacterial cell with phosphotungstic acid. The new staining technic also reveals structural details of the capsule. The described procedure was found to be useful in controlling the development of the bacterial capsule depending on culture media for propagation and maintenance of the above mentioned bacteria.

Alcian Blue↗
PubMed1975

Stains for A, B, and D cells in fetal rat islets.

Ten techniques often used for identification of A, B, and D cells in adult islets of Langerhans were applied to fetal rat pancreas. Modifications were tried with many of these techniques. Two indole methods (xanthydrol and postocoupled benxylidene reactions) and a cryostat technique using o-phthaladehyde failed to stain fetal islets. Phosphotungstic acid hematoxylin and lead hematoxylin lightly stained fetal A cell granules in Helly's fixed tissue. The Grimelius silver nitrate technique stains adult rat A cells but failed to stain fetal cells. A modification of this technique stained fetal A cells and a possible 4th cell type. The specificity of this method was confirmed by restaining stained cells with a fluorescent antibody technique and with pseudoisocyanin. B cells, as previously reported, were readily stained by the aldehyde fuchsin technique. Fetal D cells were not stained by the Hellerstrom-Hellman alcoholic silver nitrate method, nor did they display pseudoisocyanin metachromasia after acid hydrolysis; they did fluoresce brightly with this technique when viewed with UV light. It was thus possible to distinguish the three usual cell types, plus a possible fourth type, in the fetal rat pancreas.

Animals↗
PubMedDate not supplied

Morpho-structural variations of bacterial spores after treatment in steam vacuum assisted autoclave.

This study intended to verify, through microbiological techniques and TEM investigations, the killing of bacterial spores after treatment in steam autoclave, and to propose strictly morphological considerations about the target of this sterilisation process. Autoclave is the most common device for sterilising instruments in order to prevent cross infections in dental offices. The autoclave efficiency has been improved in the last years and part of this improvement is related to both a better and more correct use of the autoclave system and to the technological innovations introduced in the last generation of devices. However, associations as ADA or CDC suggest to regularly verify the process of 'autoclaving' through biological indicators (BI). The most commonly used BI are made of spores strips or suspensions of Bacillus Subtilis (pb 168) and Bacillus Stearothermophilus (ATCC 10149). They visually prove, changing colours on enzymatic base, the death of micro-organism and if the physical parameters, necessary for sterilisation, have been achieved. These two strains of endospore-forming bacteria were processed and prepared following two different techniques: Karnovsky fixed and epon embedded--phosphotungstic acid fixed for direct observation. The kind and the extent of analysed modifications are extremely various: from deep lacerations, which changed the spore structure, to little clefts which let the cytoplasm go out.

Bacillus subtilis↗
PubMed1983

Papanicolaou staining--a review.

Some technical aspects of Papanicolaou staining are reviewed. The history of the technique is traced from Mallory's aniline blue technique through Masson's trichrome procedure to the techniques of Shorr. The histochemistry of the three Papanicolaou staining solutions (aluminum-"hematoxylin", OG and EA) is discussed. The structure of the aluminum-hematein chelate and its mode of action are considered. A tentative mechanism is proposed for the characteristic differential counterstaining produced by Papanicolaou techniques, i.e. orangeophilia vs cyanophilia. It is suggested that differential counterstaining occurs as a consequence of 1) differences in cytoplasmic density, 2) differences in the molecular size of the anionic dyes, and 3) the inhibitory effects of phosphotungstic acid on the binding of small dyes. The review considers some recent quantitative studies of Papanicolaou stained cells and outlines some modifications of Papanicolaou's procedures. The text concludes with a discussion of alternatives to the Papanicolaou technique.

Aluminum↗
PubMed1978

Differential dichrome staining of tissue culture monolayers: alternate dyes and possible mechanism.

A polyacid-dependent dichrome has been devised which will differentiate epithelial from mesenchymal cells in young dividing primary cultures. Epithelial cells and colonies and nuclei are stained with metanil yellow, the stain is fixed and differentiated with phosphotungstic acid, and the mesenchymal elements are stained with toluidine blue. Several other dyes are tested for substitution in this method. Biebrich scarlet and aniline blue could be substituted for the metanil yellow; Bismarck brown T, Janus green B, crystal violet, and neutral red could be substituted for the basic dye.

Cell Nucleus↗