PubMed Health⌕ Search

Biomedical subjects

J C Stockert

Publications and source records attributed to J C Stockert.

At least 91 records · Page 5Linked to original sources
PubMed1986

Pyronin-phosphotungstic acid: spectral characteristics and staining pattern on Epon semithin sections.

Phosphotungstic acid (PTA) binds to the basic dye pyronin Y to give a non fluorescent complex with absorption characteristics which are different from those of the free dye. The use of this complex on different cells and Epon embedded tissues revealed no staining affinity and only certain hydrated tissue components as starch showed a light reaction with the pyronin-PTA. The role played by the hydratation degree of certain components from epoxy-embedded tissues on the reaction mechanisms observed with some dyes and electron contrasting agents is briefly discussed.

Animals↗
PubMed1986

Fluorescence reactions of orcein: new applications for an old stain.

The fluorescence properties of orcein are described in this paper. Under suitable exciting light, acidic solutions of orcein showed emission peaks at 587 nm (low concentration) and at 620 nm (high concentration). In fluorescence microscopy an intense orange-red emission was found in the cytoplasm and nucleoli from acetic orcein squashes of meristematic cells, as well as in the cytoplasm of Ehrlich tumour cells and in chicken erythrocyte nuclei. When semithin sections of Epon-embedded tissues were treated with orcein, a strong fluorescence reaction (orange-red) appeared in starch granules, cell walls, elastin, collagen, reticulin, keratohyalin, chromatin and mucin. Cytofluorometric measurements of orcein-stained chromatin revealed an emission peak at 585 nm with a shoulder at 620 nm. These spectroscopic and microscopical results suggest the possibility of employing orcein as a fluorochrome.

Adrenal Glands↗
PubMed1986

Electronmicroscopical contrast by palladium chloride.

Thin sections of glutaraldehyde-fixed, epoxy resin-embedded bone marrow from rats were treated with 2% palladium chloride in 2% concentrated HCl. This procedure was found to induce high electron density in chromatin from all cell types and in cytoplasmic granules of neutrophils and eosinophils. In the latter, the crystalline body showed more contrast than the matrix.

Bone Marrow↗
PubMed1986

Oxidized p-phenylenediamine: observations on the staining reaction in epoxy embedded tissues.

p-Phenylenediamine (PPD) is easily oxidized to brown compounds which stain acidic substrates. On account of the spontaneous oxidation process, the colour of PPD increases and becomes ochre-brown in a few days, showing an absorption peak at lambda = 510 nm with shoulder at about 440 to 460 nm. Studies on the application of oxidized PPD as a stain for semi-thin sections revealed that some tissue components could be clearly visualized. After glutaraldehyde fixation, semi-thin and thin sections of animal tissues were treated with 0.5% aqueous PPD solutions which were aged for variable times at room temperature. Microvilli, goblet cell mucin, mast cell granules, cartilage matrix, collagen, elastin, keratohyalin granules, acrosomes, cytoplasmic granules of Drosophila hydei salivary glands and chromatin showed positive staining reactions after treatment of semi-thin sections with oxidized PPD (7-10 days aged) for 20-30 minutes. Microspectrophotometric studies revealed an absorption peak at lambda = 520-530 nm and a shoulder at lambda = 440-460 nm in goblet cell mucin stained by oxidized PPD. In the presence of anionic macromolecules, the main peak of oxidized PPD solutions showed a strong hyperchromism. Thin sections stained by oxidized PPD did not appear contrasted, but the treatment with 0.125% gold chloride (AuCl3) induced massive gold deposits in structures stained by oxidized PPD. Hyperchromic shifts were also produced in oxidized PPD solutions after the addition of small amounts of AuCl3. This procedure can be used as a simple and rapid staining method for epoxy sections, giving selective contrast for some tissue components.

Animals↗
PubMed1985

Photosensitizing dyes and fluorochromes as substitutes for 33258 Hoechst in the fluorescence-plus-Giemsa (FPG) chromosome technique.

Using Allium cepa chromosomes after 5-bromo, 2'-deoxyuridine (BrdU) incorporation, we studied several acid and basic dyes and fluorochromes for their potential as substitutes for 33258 Hoechst in the fluorescence-plus-Giemsa (FPG) technique. All of the dyes and fluorochromes investigated showed a photosensitizing capacity which was slightly lower than 33258 Hoechst in the cases of daunomycin, phloxin, fluorescein, thioflavine T and nuclear fast red, and somewhat higher in the case of eosin Y. Observation and cytophotometric analysis of differentially Giemsa-stained sister chromatids when eosin Y was used as the photosensitizing agent revealed the unsubstituted chromatid to be reddish violet in colour (absorption maximum, 550 nm), while the BrdU-substituted chromatid was blue or pale violet blue (absorption maximum, 580 nm). These results indicate that eosin Y is a useful photosensitizing dye which could be used as a substitute for 33258 Hoechst in the FPG staining technique.

Bisbenzimidazole↗
PubMed1985

Fluorescence reaction of leukocyte granules by morin.

After treatment of blood smears from human, chicken, pigeon, pig, mouse, rabbit, lamb and horse with aqueous or hydroalcoholic solutions of morin, cytoplasmic granules in heterophil and eosinophil leukocytes fluoresce in a bright yellow colour under violet-blue exciting light. Alkaline solutions of morin show an absorption maximum at 390 nm. Under excitation at 440 nm, peaks of fluorescence emission at 505, 530, 550 or 570 nm are found, in dependence on the concentration, solvent and pH. Extraction and blocking procedures applied on pig and chicken blood smears suggest that stacking interactions of morin with basic components and perhaps with metal cations could be implicated in the specific fluorescence of acidophilic granules. The morin fluorescence reaction permits the precise visualization of eosinophil and heterophil granules in a rapid way and could be useful to identify different cell lines under pathological conditions and in comparative hematologic studies.

Animals↗
PubMed1984

A simple method for the fluorescence analysis of nucleic acid-dye complexes in cytological preparations.

This communication describes a simple method for recording fluorescence emission spectra of cytological preparations using a conventional fluorescence spectrophotometer. The emission characteristics of "in situ" complexes between some basic fluorochromes (DAPI, 33258 Hoechst, acridine orange, pyronin Y, and ethidium bromide) and nucleic acid containing structures from smears of chicken blood and Ehrlich tumor cells (chromatin, basophilic cytoplasm) are briefly described.

Animals↗
PubMed1984

Orthochromatic and metachromatic staining reactions by pyronin Y on Epon semithin sections.

Semithin sections from glutaraldehyde-fixed, Epon-embedded tissues were stained by aqueous solutions of pyronin Y at increasing concentrations (from 10(-6) to 10(-3) mol). Mucopolysaccharide containing structures (e.g. mucin) were found stained in orange, meanwhile the chromatin and remaining tissue components appeared in a bright pink-red color. Cytophotometric measurements showed that a metachromatic shift occurs in the mucin content from goblet cells after pyronin Y staining at 10(-3) mol. Some features of the metachromatic reactions by cationic dyes are briefly discussed.

Animals↗
PubMed1984

Ruthenium red staining of polyanion containing structures in sections from epoxy-resin embedded tissues.

Staining by ruthenium red (0.5 mg/ml in borate buffer at pH = 9.2) has been used for light and electron microscopic visualization of polyanion containing structures in sections from glutaraldehyde-fixed, epoxy-embedded tissues. This staining technique can be applied in a simple and rapid way, showing the reactive cell components with suitable resolution and contrast. Preliminary spectrophotometric studies show the correspondence in absorption characteristics of the dye which is bound to polyanions in situ or in vitro.

Animals↗
PubMed1984

Blue molybdenum oxides: a stain for light and electron microscopy.

Blue molybdenum oxides (molybdenum blues) have been prepared from aqueous phosphomolybdic acid solutions and applied to thin and semi-thin sections of glutaraldehyde-fixed, epoxy-embedded tissues. A light blue colour and high electron opacity were found in mast cell granules, the secretion content of goblet cells, and cytoplasmic granules in Drosophila salivary glands. The possibility that binding of blue molybdenum oxides to polyhydroxylic components accounts for the staining and contrasting reactions in some cell structures is briefly discussed.

Animals↗
PubMed1984

[Visualization of specific leukocyte granules using morin and other fluorochromes].

The visualization of the specific granulation of leukocytes is useful in hematology to identify de cell type in leukemic diseases. The authors employed the acidic fluorochrome morin after testing its high affinity for the fluorescent reaction with morin in human and chicken peripheral blood smears, and in streak smears from rabbit spleen. The best results were obtained with a solution prepared either with 0.10 mg morin per ml of 50 per 100 ethanol, or with a saturated solution of morin in distilled water diluted to one fourth in 25 per 100 ethanol. When observed under blue-violet excited light (436 nm) the acidophilic granules of leukocytes produce a bright yellow fluorescence, while the cell nuclei show a faint greenish fluorescence. As for the mechanism of the reaction, it consists possibly in an interaction between morin and the basic components of the granules. Other acidic fluorochromes, as primulin and hematoxylin, produce similar fluorescent reactions with the acidophilic granules.

Animals↗
PubMed1983

A neighbour-exclusion intercalating model for poly(ADP-ribose) binding to DNA.

Molecular model building studies have shown that a poly-intercalative binding of poly(ADP-ribose) to DNA is sterically possible. In this model, poly(ADP-ribose) lies in the minor groove of DNA and adenine bases intercalate in a neighbour-exclusion mode. This binding mechanism could be used to recognize neighbour-exclusion intercalative sites on DNA.

DNA↗