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PubMed1979

Different aspects of membrane differentiation at the inner side (GERL) of the Golgi apparatus in rabbit luteal cells.

After luteinization, during the growth phase, rabbit luteal cells showed a well-developed Golgi apparatus, which was clearly reduced at the end of pseudo-pregnancy. During this whole period, acid phosphatase was demonstrated in the saccules (g) of the Golgi stack and in the innermost Golgi element (G2), which may be part of GERL. Between both acid phosphatase-positive compartments, a negative or slightly positive element (G1) was present paralleling the saccules of the Golgi stack. This element was composed of cisternal (G1 c) and perforated portions (G1 p) and directly bordered the thiamine pyrophosphatase-positive saccules of the Golgi stack (g1 -g2). Arylsulphatase activity was present in two saccules in the middle of the stack (g3 -g4) and in the innermost Golgi element (G2). In the acid phosphatase and arylsulphatase reactions the limiting membrane of the lysosomes was more reactive than the matrix. After phosphotungstic acid staining at a low pH, the inner elements of the Golgi apparatus (G1 and G2) and the border of the lysosomes were heavily contrasted. The lysosomal matrix and the other Golgi stack saccules were either almost unstained or displayed a clearly lower contrast. It is concluded that the cytochemical difference between Golgi (g) and GERL (G) membranes is most probably the result of a specific process of membrane differentiation, which takes place at G1. There is also evidence that the lysosomal matrix hydrolases may be formed in the saccules of the Golgi stack. The strongly phosphotungstic acid-positive inner elements are, although more extended, comparable in large part with the GERL elements as described in neurons (Novikoff et al., 1971).

Acid Phosphatase↗
PubMed1976

Fine structure and cytochemistry of specific granules in the lamprey atrium.

Fine structural and cytochemical studies were performed to examine the nature of three types of specific granules found in the atrium of lamprey; specific granules of the atrial muscle cell (ASG), interstitial cell granules (ICG) and endocardial endothelial granules (ESG). Ultrastructurally, ASG and ICG appeared quite similar in size, shape and electron opacity, while ESG were much larger and less dense in opacity than the other two. None of the granules showed positive DAB reaction or acid phosphatase reaction. Only ICG revealed positive chromaffin reaction, which agreed with formaldehyde induced green fluorescence along the atrial lumen. Phosphotungstic acid at low pH stained ICG and ASG strongly positive, and ESG weakly positive. Pronase treatment in Epon sections for 24 h digested ASG alone, whereas in glycol-methacrylate embedded sections, ESG were digested first, ASG were digested thoroughly after 30 min, but ICG were not digested completely after 90 min. From these results it can be concluded that the three types of specific granules have different constituents. ESG consist of protein with some polysaccharides; ASG are composed of protein carbohydrate complexes and lack catecholamines; ICG contain catecholamine as well as protein carbohydrate complexes.

Acid Phosphatase↗
PubMed1993

Cytochemical and immunocytochemical ultrastructural study of nucleoproteins during nucleologenesis in 8-cell bovine embryos.

The aim of this study was to characterize embryonic nucleologenesis by determining the appearance and localization of acid argyrophilic, basic lysine-rich and histone proteins in 8-cell bovine embryos. Two silver staining techniques, ethanolic phosphotungstic acid (PTA) and immunocytochemical methods using specific antibodies, were applied at the ultrastructural level. The silver-stained proteins were detected at the onset of nucleologenesis on the periphery of the dense nucleolus precursor bodies (NPBs). The amounts of these proteins increased during the transformation of the NPBs into the fibrillogranular nucleolus. At this stage the well-developed dense fibrillar components encircling fibrillar centres showed intense staining. PTA-positive (basic lysine-rich) proteins were present within most nucleolar structures during nucleologenesis as well as in the chromatin. Histones H2B, H3 and H4 were concentrated throughout the chromatin including the nucleolus-associated chromatin. At the onset of nucleologenesis, histones were absent in the NPBs. The first weak histone labelling was detected in the multivacuolated NPBs, both in the fibrous mass as well as inside the vacuoles. Nucleolar histones appeared with the massive penetration of DNA into the NPBs. We suggest that nucleologenesis may serve as a criterion of normal early embryonic development and that the proteins involved in the process of nucleologenesis and transcription could be used as chemical markers of nucleolar function.

Animals↗
PubMed1992

Cytochemical characterization of the cuticle of Caenorhabditis elegans (Nematoda: Rhabditoidea).

At the ultrastructural level, the Caenorhabditis elegans (Maupas, 1900; Doughert, 1953) cuticle shows the presence of six layers: epicuticle, external cortical, internal cortical, intermediate, fibrous and basal. Two techniques were used for carbohydrate localization: the periodic acid-thiosemicarbazide-silver proteinate (Thiéry) and gold-labelled lectins. No labelling was found on the nematode's cuticle. With the ethanolic phosphotungstic acid technique (E-PTA), that detects basic proteins, reaction product was observed in the outer cortical layer, in the cuticle struts and in the dense bodies of the muscle cell. Surface anionic sites of C. elegans were visualized by using cationized ferritin particles, at pH 7.2, and by using colloidal iron hydroxide particles at pH 1.8. Treatments with trypsin and neuraminidase (Vibrio cholerae) did not interfere with the binding of the cationic particles to the nematode's surface. In contrast, treatment with chondroitinase ABC, a specific enzyme for glycosaminoglycans, significantly reduced the binding.

Animals↗
PubMed1992

A non-toxic method for the demonstration of gliosis.

Neuropathology laboratories have traditionally relied upon the Holzer method for demonstration of gliosis. However, concerns about the toxicity of aniline oil have markedly reduced the application of this method in recent times. Immunostains for glial fibrillary acidic protein (GFAP) are excellent for showing gliosis in grey matter but cannot distinguish normal from abnormal astrocytes in the white matter. The traditional phosphotungstic acid hematoxylin (PTAH) method stains myelin as well as glial fibers and, thus, is not useful for recognizing areas of gliosis. Here we present a method for the routine demonstration of gliosis based on a modification of Mallory's PTAH method. The staining of myelin is eliminated by increasing the concentration of potassium permanganate to 5% (from 0.25-1% in traditional methods). The use of aminoalkylsilane adhesive ensures that the sections do not detach during the procedure. Areas of gliosis stand out against a pale background because only abnormal astrocytes and their processes are stained, both in grey and white matter. The method minimizes the use of toxic chemicals and can be completed within an eight hour work day in any routine neurohistology laboratory, using formalin fixed, paraffin-embedded tissue.

Evaluation Studies as Topic↗
PubMed1993

Inflammatory polyarthritis in mice transgenic for human T cell leukemia virus type I.

OBJECTIVE: We have recently reported that arthropathy develops in high incidence among transgenic mice carrying the pX region of human T cell leukemia virus type I (HTLV-I). In the present study, the histopathologic features of the joints in these mice were examined in order to compare the animal disease with rheumatoid arthritis (RA) in humans. METHODS: Paraffin sections of limbs (right and left fingers, wrists, elbows, shoulders, toes, knees, and ankles) were stained with hematoxylin and eosin, periodic acid-Schiff, azan-Mallory, or phosphotungstic acid hematoxylin, and examined by light microscopy. RESULTS: Abnormalities of the limbs began to occur as early as 3 weeks of age, and the incidence gradually increased until the mice were 12 months old. The incidence of arthropathy was 22% (48 of 217) at 3 months of age and 28% (18 of 64) at 6 months. The severity of the histopathologic changes in the joints of the transgenic mice ranged from grade I to grade IV. CONCLUSION: The major histopathologic features in the joints of HTLV-I transgenic mice are similar to those in humans with RA. Thus, these mice may represent a useful model for the study of the disease in humans.

Animals↗
PubMed1982

Carbohydrate cytochemistry on hypodermic lymphatic endothelium of the green lizard, Lacerta hispanica.

A cytochemical study on the endothelium of the hypodermic lymphatic capillaries of the green lizard, Lacerta hispanica, has been carried out. The dialysed iron method produced a homogeneous precipitate on the surface of the endothelial cells and on the inside of the endocytic vesicles. The periodic acid-thiocarbohydrazide-silver proteinate, low pH phosphotungstic acid and high iron diamine techniques gave negative results. The carbohydrates in the capillaries thus seem to be glycosaminoglycans with carboxyl groups. The possible role of these glycosaminoglycans in the formation of the endocytic vesicles is discussed.

Animals↗
PubMedDate not supplied

A staining sequence for the differentiation of A-, B-, and D-cells of the islets of guinea-pig pancreas.

Four mu sections of guinea-pig pancreas that had been fixed in Bouin's fluid were deparaffinized, hydrated, oxidized in equal volumes of 0.3% KMnO4 and 0.3% H2SO4, decolorized in 2% oxalic acid and stained in 1% alcian blue in 70% alcohol for 10 min. Next they were stained for 5 min in chrome hematoxylin then into a dilute aqueous acid fuchsin solution followed by 2% phosphotungstic acid for 1 min. They were washed in running water until only the A-cells retained the red stain and were then counter stained with alcoholic aurantia for 5 min. Finally, the sections were cleared in xylene and mounted in D.P.X. Within the islets, B-cells stained blue green, A-cells bright red, D-cells pale yellow, while the acinar tissue stained blue grey. The wide separation between these colors represents a considerable advance on previous techniques for individual cell recognition within the islet.

Alcian Blue↗
PubMed2001

Evolution of the composition of a selected bitter Camembert cheese during ripening: release and migration of taste-active compounds.

The aim of this study was to add to the understanding of changes in taste that occur during the ripening of a bitter Camembert cheese by the evolution of its composition. Physicochemical analyses were performed on rind, under-rind, and center portions of a Camembert cheese selected for its intense bitterness. At each of the six steps of ripening studied organic acids, sugars, total nitrogen, soluble nitrogen, phosphotungstic acid soluble nitrogen, non-protein nitrogen, Na, K, Ca, Mg, Pi, Cl, and biogenic amines were quantified in each portion. Changes in cheese composition seemed to mainly result from the development of Penicillium camemberti on the cheese outer layer. Migration phenomena and the release of potentially taste-active compounds allowed for the evolution of saltiness, sourness, and bitterness throughout ripening to be better understood. Apart from taste-active compounds, the impact of the cheese matrix on its taste development is discussed.

Carbohydrates↗
PubMed1987

A staining method for easy detection of eosinophilic globules in Kaposi's sarcoma.

Eosinophilic globules provide an important clue for diagnosis of Kaposi's sarcoma (KS). These globules were stained with periodic acid Schiff (PAS), periodic acid Schiff reagent after diastase digestion, phosphotungstic acid hematoxylin (PTAH) and autofluorescence under ultraviolet illumination. By these methods, however, eosinophilic globules in KS could not be readily identified. Therefore, we developed a new procedure for rapid identification of eosinophilic globules in KS tissues.

Humans↗
PubMed2002

[Effects of aqueous extract in herba of Lysimachia christinae on hyperuricemia in mice].

OBJECTIVE: To study hypouricemic effect of aqueous extract of Lysimachia christinae on hyperuricemia in mice. METHOD: The uricase inhibitor potassium oxonate was used to induce hyperuricemia in mice, and serum uric acid level was determined with the phosphotungstic acid method. RESULT: The aqueous extract of Lysimachia christinae, when administered orally to the oxonate-induced hyperuricemic mice at the doses of 5.2, 10.4 and 20.8 g.kg-1, was able to elicit dose-dependent hypouricemic effects. At these doses of the extract, the serum urate levels of the oxonate-pretreated mice showed no difference from the normal mice. In normal mice, however, oral administration of the extract at the same doses did not produce any observable hypouricemic effects. CONCLUSION: The aqueous extract of Lysimachia christinae possesses potent hypuricemic effects on models of hyperuricemia in mice pretreated with oxonate.

Animals↗
PubMed1978

[Ultrastructural cytochemistry of human spermatozoa].

Enzymatic activities and repartition of glycoproteins were studied with electron microscopy in human ejaculated spermatozoa. Enzymatic activities are localised in the head of spermatozoon: arylsulfatase in the acrosome, acid phosphatase in the periacrosomal cytoplasm. Phosphotungstic acid at low pH and colloïdal iron allow detection of glycoproteins and acid groups on the sperm cell surface. Glycoproteins are present in the acrosome. These results are slightly different to those obtained in other species.

Acid Phosphatase↗
PubMed2006

Light-induced degradation of perfluorocarboxylic acids in the presence of titanium dioxide.

The UV-photon-induced degradation of heptafluorobutanoic acid was investigated in acidic aqueous solutions in the presence of titanium dioxide. Heptafluorobutanoic acid could be degraded with this photocatalyst in a light-induced reaction generating carbon dioxide and fluoride anions. Carbon dioxide evolution in a significant amount occurred only in the presence of molecular oxygen and the photocatalyst. The light-induced degradation of trifluoroacetic acid, pentafluoropropanoic acid, nonafluorobutanoic acid, pentadecafluorooctanoic acid, nonafluorobutanesulfonic acid, and heptadecafluorooctanesulfonic acid in the presence of titanium dioxide was also studied. The perfluorocarboxylic acids under investigation are degraded to generate CO(2) and fluoride anions while both perfluorinated sulfonic acids are persistent under the experimental conditions employed in this study. For all compounds photonic efficiencies of the mineralization reaction were estimated to be smaller than 1x10(-5). To increase the photocatalytic activity mixed systems containing homogeneous phosphotungstic acid and heterogeneous titanium dioxide catalysts were also investigated. In the mixtures of these two photocatalysts, the formation rate of CO(2) increased with illumination time.

Alkanesulfonic Acids↗
PubMed1989

A cytochemical study of dense granules in the rat junctional epithelium.

To clarify the details of intracytoplasmic granules in the junctional epithelium (JE) of the rat gingiva, phosphotungstic acid (PTA) staining, acid phosphatase cytochemistry and zinc iodide-osmium (ZIO) staining were carried out. Condensing granules containing homogeneous electron-dense materials, measuring about 260 nm in diameter, have been observed at the peripheral cytoplasm of the JE. These granules reveal PTA-positive, ZIO-positive and acid phosphatase-positive staining. These results indicate that the granules contain glycoprotein, phospholipid, lipoprotein and lysosomal enzymes. From their composition and morphology, it is suggested that these granules in the JE may contribute secretory function and secrete glycoproteins or glycolipids. Although it is unclear whether the dense granules correspond to membrane-coating granules by our staining methods, it is surmised that, if the dense granules can engage in establishment of the barrier function, then this role is impeded by the large intercellular space in the JE.

Acid Phosphatase↗
PubMed1993

Analysis of the endocytic-lysosomal system (vacuolar apparatus) in astrocytes during proliferation and differentiation in primary culture.

The endocytic-lysosomal system of proliferating and differentiated astrocytes in primary culture was investigated using a combination of cytochemical, immunocytochemical and biochemical procedures. These included impregnation with osmium tetroxide and potassium iodide, phosphotungstic acid staining, cytochemical demonstration of acid phosphatase and thiamine pyrophosphatase activities and incorporation of cationized ferritin. The acid phosphatase activity was also analyzed using biochemical techniques. Our results indicate that while all astrocytes in primary culture have a developed endocytic-lysosomal system, this system is different in proliferating cells from that in differentiated astrocytes. Whereas in proliferating astrocytes it appears to be composed mainly of a variety of vacuoles and vesicles displaying a heterogeneous osmium tetroxide staining pattern, differentiated cells are characterized by the presence of small size vesicles showing an intense reaction. Both types of astrocyte showed abundant lysosomes, including multivesicular bodies, which presented an intense phosphatase acid activity. Biochemical analyses demonstrated that this activity increase during the proliferation period, reaching a maximum at 15 days of culture. Incorporation of cationized ferritin revealed that lysosomes and endosomes constitute separate systems. Finally, we have also found that the activity of thiamine pyrophosphatase, a marker for the Golgi complex, increases throughout the culture period. These results indicate that astrocytes could play an important role in regulating the macromolecular composition of the extracellular space.

Acid Phosphatase↗
PubMed1990

Ultrastructural cytochemical methods in the study of mouse testicular tissue.

Different cytochemical and immunocytochemical techniques employed in processing of mouse testicular tissue at ultrastructural level were compared. Two silver staining procedures applied en block and on ultrathin Lowicryl sections were used to demonstrate acidic argyrophilic nuclear proteins. Both methods give standard results. Silver staining en block gives positivity in the form of fine silver precipitate. Coarser silver aggregates and fine nonspecific reactions of the background result from silver staining on ultrathin sections. The method with alcoholic phosphotungstic acid applied en block was used to demonstrate basic nuclear proteins rich in lysine. The results are confirmed and specified by immunocytochemical demonstration of histones and protamine. Specificity of the reactions is briefly discussed.

Acrylic Resins↗
PubMed1975

Localization and characterization of carbohydrates in adrenal medullary cells.

The localization and characterization of carbohydrates in adrenal medullary cells were studied by histochemical and cytochemical methods. Adrenaline (A)-and noradrenaline (N)-storing granules were argentaphobic when ultrathin sections of Araldite-embedded medullae were stained according to the periodic acid-thiocarbohydrazide-silver proteinate technique of Thiery. A small amount of glycogen in the form of single beta-particles as well as lysosomes were, however, visualized by this technique. The entire core of the A granules was markedly positive after ultrathin sections of glutaraldehyde-fixed, glycol methacrylate (GMA)-embedded medullae were stained with phosphotungstic acid (PTA) at low pH (0.3). The N granules, in contrast, were mostly unreactive. In the A cells, PTA stained a large part of the Golgi complex, whereas in the N cells the Golgi complex was mostly unstained. In both cell types, the cell coat, lysosomes, and multivesticular bodies reacted to PTA. The periodic acid-Schiff (PAS) technique showed A but not N granules in semithin sections of GMA- or Araldite-embedded medullae. The PTA and PAS stains were abolished by acetylation, restored by saponification, unchanged by methylation, and greatly diminished by sulfation. In ultrathin sections of GMA- or Araldite-embedded medullae incubated with colloidal iron according to various techniques, the cell coat and lysosomes of both cell types were stained, unlike all the other cytoplasmic organelles. These results indicate that A granules and the Golgi complex of A cells, unlike the same structures in N cells, are rich in glycoproteins which are probably not acidic.

Adrenal Medulla↗
PubMed1986

[Silver impregnation of myelin sheaths].

A method is described, based on mordantiation with phosphotungstic acid and tannic acid plus impregnation with silver nitrate solution (pH 10.4) and a physical developing technique. Water glass is used as a protective colloid in the developer.

Histocytochemistry↗