The pathological study of enterosiderosis in guinea pigs

Enterosiderosis in both SPF Hartley guinea pigs and vitamin C-deficient animals of the same strain were studied by light and electron microscopy. Enterosiderosis was detected in all animals in the present study. Macrophages, inclosing yellowish-brown pigments and erythrocytes, appeared in the lamina propria of the intestinal mucosa, mainly in the cecum. These pigments in the macrophages were positive for Prussian blue, PAS and the Nile blue reaction. Residual bodies containing highly electron-dense ferritin-like particles, lipofuscin granules and debris of phagocytized erythrocytes were found by electron microscopy in the macrophages. In vitamin C-deficient guinea pigs, the number of macrophages, including the same above pigments, appeared in the lamina propria of the intestinal mucosa, and there was severe enterosiderosis. In the absorptive cells of the intestinal mucous membrane, granules positive for the Prussian blue reaction appeared only in the duodenum. These findings strongly suggest that the pigments in the macrophages in enterosiderosis of the guinea pigs were mixtures of iron and lipofuscin granules and that the iron is derived from erythrocytes phagocytized by macrophages in the lamina propria, but not from iron absorbed by epithelial cells.     

An Application of the Prussian Blue Technique to a Light Microscope Study of Water Movement in Transpiring Leaves of Cotton (Gossypium hirsutum L.)

Prussian blue deposition in transpiring leaves of Gossypiumhirsutum L. indicated that water moved rapidly from the trachearyelements by a path along the bundle sheath parenchyma to thebundle sheath extension parenchyma and then laterally throughthe epidermis to the sub-stomatal cavities or to the tnchomes.A slower pathway of water movement to the substomatal cavitiesoccurred through the mesophyll. The path of Prussian blue depositionindicated that waterleft the leaf through the stomata and toa lesser extent through the trichomes. In the outer periclinalwall of epidermalcells Prussian blue was deposited below butnot within the cuticle.     

INTRANUCLEAR AGGREGATES OF FERRITIN IN LIVER CELLS OF MICE TREATED WITH SACCHARATED IRON OXIDE : Their Possible Relation to Nuclear Protein Synthesis

Several months following parenteral injections of saccharated iron oxide into DBA/2J mice, granules rich in iron were found in nuclei of scattered parenchymal liver cells as well as in the cytoplasm. As seen in the light microscope, the intranuclear granules were brown; most of them measured between 0.5 µ and 1 µ in cross-section. They gave positive Prussian blue tests, and were not selectively stainable with pyronine. Electron micrographs of the granules showed closely packed aggregates of ferritin molecules, occasionally in paracrystalline order. The intranuclear collections were often surrounded by bands of material of moderate opacity. Scattered ferritin molecules and collections of such molecules were also present in the cytoplasm of many liver cells, but there seemed to be no quantitative relationship between intranuclear and cytoplasmic ferritin. Liver cells from untreated control mice failed to reveal intranuclear deposits of ferritin. Although the site of origin of the intranuclear aggregates of ferritin is unknown, the findings suggest the possibility that under suitable circumstances ferritin synthesis may take place within nuclei of liver cells—perhaps induced by the presence of colloidal iron.     

An Electron Microscope Study of the Path of Water Movement in Transpiring Leaves of Cotton (Gossypium hirsulum L.)

Precipitation of ferrocyanide by ferric ions in cotton leavesproduced electron-opaque crystals visible with othe electronmicroscope and identifiable as Prussian blue by X-ray and electrondiffraction. These crystals were formed within the lumina andexposed primary walls of the tracheary elements but not withintheir secondary walls. The precipitation pattern indicated thatwater moved from the tracheary elements into the parenchymaof the bundle sheath and bundle sheath extensions. From thesecells water moved into the epidermis or through the mesophyllto the transpirational exits. Prussian blue accumulated in thewalls of cells lining the substomatal cavities and to a lesserextent between adjacent covering hairs. Ferrocyanide anionsdid not follow the water stream through the cuticle. In parenchymaand epidermal cells Prussian blue crystals were found withinthe primary wall, in the region between the plasma-lemma andthe cell wall, and within the protoplast.     

Ultrastructural silver enhancement of Prussian blue-reactive iron in hematopoietic and intestinal cells

Prussian blue has been widely used to localize iron in a variety of tissues at the light and electron microscopic level. In the present study, thin sections of human marrow and blood cells and rat duodenal cells were exposed to silver proteinate (SP) after staining en bloc with acid ferrocyanide (AF), with and without prior iron saturation using iron nitrilotriacetate (FeNTA). Silver deposition was observed over Prussian blue-reactive sites and significantly enhanced sites of minimal AF and FeNTA-AF staining. AF-SP stain deposits were present in the cytoplasmic matrix, granules, and occasionally on the surfaces of macrophages, monocytes, and erythroblasts. FeNTA-AF-SP stained additional cytoplasmic and surface sites in erythroblasts and stained neutrophil granules intensely. Duodenal epithelium from iron-loaded rats demonstrated strong AF-SP staining of ferric iron in microvilli, apical cytoplasmic matrix, and lateral membranes. Similar preparations from iron-replete rats stained sparsely; however, intense AF-SP staining was observed after iron saturation with FeNTA. SP similarly enhanced luminal ferrous iron deposits stained with acid ferricyanide in rats given intraluminal ferrous iron. AF-SP stain deposits were removed by exposure of thin sections to NH4OH, KCN, or HNO3 but were not affected by prior exposure to HIO4 or NaBH4, consistent with a silver cyanide or complex stain precipitate rather than reduced silver or silver ferriferrocyanide. SP enhancement of Prussian blue allows identification of reactive sites not readily visualized with AF or FeNTA-AF alone, and offers the potential for differentiating AF staining from other deposits or organelles of comparable density.     

Precipitation of iron in windowpane oyster shells by marine shell‐boring Cyanobacteria

Shells of windowpane oyster [Placuna placenta (L)] in the intertidal zone of the Zuari estuary, Goa, were often found to be black in color. Microscopical observation of partially decalcified shells showed the presence of cyanobacterial filaments encrusted with black precipitate. Microchemical test (Prussian blue reaction) and wavelength dispersive x‐ray analysis confirmed this precipitate to be of iron. Mineralogical studies of this black precipitate, using x‐ray diffraction and scanning electron microscopy, suggested the presence of iron as iron oxides. The cyanobacteria from such black shells were cultured in enriched seawater medium. In this medium also they precipitated iron as confirmed by Prussian blue reaction. They were identified as Plectonema terebrans Born et Flah and Phormidium sp.     

A study on the cytoplasmic granules of the pericardial gland cells of some bivalve molluscs

The pericardial glands of three bivalve molluscs are composed of convoluted epithelium that appears as pouches on the auricles of Mytilus and as tubules in the connective tissue at the anterior-lateral sides of the pericardial cavity of Mercenaria and Anodonta. The pericardial gland cells are attached to each other by many randomly placed desmosome-like cell junctions and gap junctions. Belt-desmosomes that are characteristic of epithelial cells were not observed. The basal membrane of these cells is invaginated producing complex interdigitating cytoplasmic processes and filtration slits. The pericardial gland cells stain for the presence of iron with Prussian blue stain. Electron-dense and electron-lucent granules of various diameters are present in the cytoplasm. Many electron-dense granules contain ferritin-like particles in which the presence of iron has been demonstrated by microanalysis. It is suggested that these particles are the iron storage protein ferritin since they contain iron, and are water soluble, heat stable, and morphologically similar to mammalian ferritin. Ferritin particles are probably both synthesized and broken down by the pericardial gland cells; thus the pericardial gland cells may be involved in iron homeostasis in these molluscs.     

The suberin lamella,a possible barrier to water movement from the veins to the mesophyll ofThemeda triandra forsk

Summary Precipitation of ferrous ions by ferricyanide in transpiring leaves ofThemeda triandra Forsk. produced crystalline deposits, which were visible with the light and electron microscope. Prussian blue crystals were formed within the lumina of the tracheary elements and the apoplast, or cell wall continuum of the vascular tissues and bundle-sheath cells. Little if any deposition was noted within the lignified secondary thickenings of the tracheary elements. The localization pattern suggests that the ferrous ions moved from the lumina of the tracheary elements via the exposed primary walls. Prussian blue crystals were abundant in the outer tangential and radial walls of the bundle-sheath cells. By contrast, crystals were lacking in the walls of neighbouring mesophyll cells, suggesting that the suberin lamella in the bundle-sheath walls effectively inhibited the apoplastic movement of ferrous ions and possibly may impede, or restrict the movement of water across the bundle-sheath/mesophyll interface.     

DIFFERENTIATION AND PROLIFERATION OF EMBRYONIC MAST CELLS OF THE RAT

Histochemical reactions and radioautography were used to investigate the sequence of mast cell development in rat embryos. Mast cells arise ubiquitously in and are confined to the loose connective tissue in the embryo. The alcian blue-safranin reaction distinguishes between weakly sulfated and strongly sulfated mucopolysaccharides by a shift from alcian blue to safranin staining. Based on this reaction and morphologic characteristics, four stages were identified. Stage I mast cells are lymphocyte-like cells with cytoplasmic granules which invariably stain blue with the alcian blue-safranin reaction. In Stage II cells the majority of granules are alcian blue-positive, but some safranin-positive granules have appeared. Stage III mast cells are distinguished by a majority of safranin-positive cytoplasmic granules; some alcian blue-positive granules still remain. Stage IV cells contain only safranin-positive granules. Thymidine-H³ uptake and identification of mitotic figures indicates that mast cells in Stages I and II comprise a mitotic pool while those in Stages III and IV are mitotically inactive. The pattern of S³⁵O₄ incorporation and the sequence of appearance of histochemically identifiable mast cell constituents corroborates division of the proliferation and differentiation of embryonic mast cells into the four stages described above. The process of formation of mast cell granules is interpreted as reflecting the synthesis and accumulation of a heparin precursor in alcian blue positive granules followed by the synthesis and accumulation of highly N-sulfated heparin along with mast cell chymase and finally histamine in safranin-positive granules.     

Blood Cell Ultrastructure of the Ascidian Botryllus schlosseri L. II. Pigment Cells

Colonies of Botryllus schlosseri L., bred in the laboratory and genetically selected as regards the blue and/or reddish pigments, were used. The following phenotypes were investigated under the electron microscope: (a) blue colonies without reddish pigment; (b) reddish colonies without blue pigment; (c) colonies with both blue and reddish pigments; (d) colonies with neither blue nor reddish pigments. In the pigmented colonies, a specialized blood pigment cell type was recognized that, in giant membrane-limited vacuoles, contained a great number of granules. In general, the granules were similar in size, not individually limited by a membrane and were made up with electrondense material often arranged in concentric rings. Although there could be some variability within the same cell, in each phenotype the granules displayed a characteristic pattern so that the differences in colour of the granules, as seen in vivo, were paralleled by differences in the ultrastructural architecture. In the unpigmented colonies also, granulated vacuolar cells, rare in number but morphologically comparable to the pigment cells, were seen. On the basis of these results, the hypothesis of the existence of a prospective pigment cell and of a common origin for all the pigment cells of B. schlosseri is discussed.     

Distribution of Iron-Containing Granules in Lampreys,with Particular Reference to the Southern Hemisphere Species Geotria australis Gray

Perl's Prussian blue and bathophenanthroline have been used to investigate the sites where iron-containing granules are found within representatives of each of the three extant families of lampreys. Amongst the larvae, granules were present in the columnar cells of the posterior intestine in small amounts in some but not all northern hemisphere species (Petromyzonidae), and in moderate and very large amounts in the southern hemisphere families Geotriidae and Mordaciidae respectively. Granules were only found in large numbers elsewhere in the body of larvae of the Geotriidae, in which they were predominant in the adipose tissue of the nephric fold and fat column. It is suggested that these large iron deposits reflect the intake of an unusually large amount of iron, a feature which in turn could be related to the relatively high plasma iron levels and haemotocrit found in larvae of the Geotriidae. During metamorphosis, iron deposits accumulate in the liver of all species as haemoglobin is broken down.     

Envenomation by the box-jellyfish Chironex fleckeri: how nematocysts discharge

The capsules of isolated mastigophores of C. fleckeri were impermeable to water and neutral red dye. After air drying, ca 30% discharged, most everting fully, when exposed to distilled water or sodium citrate but in a seawater medium only partial discharge was induced. The capsular contents of discharging mastigophores dyed strongly red with neutral red and showed metachromasy with toluidine blue. Electron micrographs revealed hexagonal arrays of granules ca 12 nm in diam. Evidence supports the view that a polymerization of the capsular material initiates tubule eversion and that complete eversion involves osmotic inflow of water and sustained compression of the capsular contents.     

The Formation of Intracellular Crystals in Midgut Glands of Limnoria lignorum

Certain morphological features of intracellular crystal formation within the midgut glands of Limnoria lignorum (Rathke) have been studied with the electron microscope and cytochemical methods. A correlation has been established between Golgi membranes and formation of the crystals. The Prussian blue reaction reveals quantities of iron localized in the intracellular crystals and in small granular structures seen in the apical region of the cells. These granules can be identified as accumulations of Golgi membranes, with which iron-containing particles are associated. When these membrane configurations are studied with the electron microscope, they can be classified and arranged in an assumed sequence which is thought to represent successive stages in the development of crystals. As the membrane systems become progressively specialized, increasing accumulations of dense granular material appear within their interstices. This material is rich in iron and probably represents the component responsible for the positive Prussian blue reaction. This material also appears to be a precursor substance for iron-containing protein molecules which are synthesized and arranged to make up the crystals. These iron-containing molecules are first deposited in orderly array as double rows of dense particles on certain internal membranes of the specialized Golgi complexes. The membranes later disappear and the particles form definitive crystals by rearrangement into a hexagonal close-packed pattern.     

鸡中枢淋巴器官肥大细胞的组织化学与形态学

对哺乳动物的,特别是啮齿动物和人类肥大细胞已有了比较深入的研究, 但关于家禽肥大细胞的研究很少.本研究旨在阐明鸡中枢淋巴器官中肥大细胞的组织化学与形态学特征.本研究证实Carnoy 氏液是鸡肥大细胞的优良的固定液,而中性缓冲福尔马林(NBF) 却阻断了大多数肥大细胞的着染力.甲苯胺蓝和阿尔新蓝是鸡肥大细胞的良好的染料,但阿尔新蓝能使更多的肥大细胞着染,虽然其也可使杯状细胞着染.作者的一种新的染色法, 长时间阿尔新蓝染色(LAB-S)可用于NBF固定的组织中肥大细胞的染色,因为其着染的细胞数与Carnoy 氏液固定甲苯胺蓝染色的细胞数无显著差异(P<0.001).在胸腺髓质中见有大量的肥大细胞,而胸腺皮质仅可见个别肥大细胞位于血管周围及小叶间结缔组织中.腔上囊的皮质与髓质中很少见有肥大细胞.肥大细胞有血管周围分布的倾向,但一个有趣的发现是血管内偶尔也有个别肥大细胞.电镜下可见肥大细胞的胞浆颗粒内充满无定形的颗粒状基质,但其电子密度有的较高,有的较低.少数胞浆颗粒内有旋涡状及网状亚微结构.但未见有人类肥大细胞胞浆颗粒内特征性的晶格状和卷轴状的亚微结构,也未见到在绵羊肥大细胞中描述过的特殊亚微结构.     

Reduction of Prussian Blue by the two iron-reducing microorganisms Geobacter metallireducens and Shewanella alga

Cyanide or cyanide-metal complexes are frequent contaminants of soil or aquifers at industrial sites, which can be released from such sites by outgassing or transport with the groundwater. They form very stable complexes with iron, which may occur in the subsurface as an insoluble blue mineral, the so-called Prussian Blue (Fe(4)[Fe(CN)(6)](3)). In this study, we show that the insoluble and colloidal Fe(III)-cyanide complex Prussian Blue can be reduced and utilized as electron acceptor by the dissimilatory iron-reducing bacteria Geobacter metallireducens and Shewanella alga strain BrY. The microbial reduction of the dark blue pigment Prussian Blue leads to the formation of a completely colourless solid mineral, presumably Prussian White (Fe(2)[Fe(CN)(6)]), which could be reoxidized through exposure to air, regaining the dark blue colour. In addition, the microorganisms were able to grow with Prussian Blue, using it as the sole electron acceptor. Geobacter metallireducens could also reduce Prussian Blue coatings on sand, which was sampled from a contaminated site.     

Comparison of Prussian blue and apple-pectin efficacy on 137Cs decorporation in rats

Cesium-137 (137Cs) is one of the most important nuclear fission elements that contaminated the environment after the explosion of the Chernobyl nuclear power plant in Ukraine (1986). The aim of the study was to compare the efficacy of two chelating agent, Prussian blue and apple-pectin on 137cesium decorporation in rats. Rats were intravenously injected with a solution of 137cesium (5 kBq per rat). Chelating agents, Prussian blue or apple-pectin were given immediately after Cs contamination and during 11 days by addition of each chelating agent in drinking water at a concentration corresponding to 400 mg kg(-1) day(-1). Efficiency was evaluated 11 days after contamination (at the end of treatment) through their ability to promote Cs excretion and to reduce the radionuclide accumulation in some retention compartments (blood, liver, kidneys, spleen, skeleton and in the remaining carcass). In these conditions after treatment with Prussian blue a fivefold increase in fecal excretion of Cs was observed and was associated with a reduction in the radionuclide retention in the main organs measured. In contrast, no significant differences were observed between untreated rats and rats treated with apple-pectin. These observations were discussed in terms of ability of pectins to bind Cs and compared to recently published results obtained after treatment of Cs-contaminated children with this chelate.     

Effect of granule size on the interference colors of starch in polarized light

Abstract

A Nikitin-Berek compensator tilted at 5.5° in a polarizing microscope was used to create a background second-order blue interference color against which starch granules were examined. A grating monochromator showed the first interference minimum of the background was at 590 nm. Starch granules have a radial molecular structure. Thus, some radii were in line with the axis of the compensator while others were across the compensator axis. Where radial birefringence counteracted the background birefringence, starch granules had two quadrants with a bright yellow first-order interference color. Where radial birefringence added to the background birefringence, there were two quadrants of second-order blue (higher than the background). In yellow quadrants where birefringence was reduced, the wavelength of the first interference minimum was reduced. In blue quadrants where birefringence was increased, the wavelength of the first interference minimum was increased. The extent to which the interference minimum of the background birefringence was shifted by starch granules was strongly dependent on the size of the starch granules. For yellow quadrants, the shifts were: r = ?0.87, P < 0.001, n = 22 for corn starch; r = ? 0.94, P <0.001, n = 22 for tapioca starch; and r = ?0.94, P <0.001, n = 12 for potato starch. For blue quadrants, the shifts were: r = 0.80, P < 0.001, n = 22 for corn; r = 0.81, P < 0.001, n = 22 for tapioca; and r = 0.93, P < 0.001, n = 16 for potato. When interference colors are used to evaluate starch granules, the granules should be similar in size or a correction must be made for granule size, and the Michel-Lévy chart of interference colors may be used to collect data subjectively.     

Metal dilution effects on the switching properties of CoFe Prussian blue analogues

Recent years have seen the discovery of unusual and fascinating electronic properties in Prussian blue analogues. Thus, some CoFe Prussian blue analogues exhibit a photomagnetic effect. Here, we present the first study of metal dilution effect on the switching properties in two different CoFe Prussian blue analogues. This investigation shows that metal dilution strongly depends on the stoichiometry of the compounds and the nature of the diluting agents. The switching properties can either be totally killed for low dilution rate or be persist at a CoFe pair scale.     

Free-space marker studies on the leaf ofZea mays L.

Summary Two free-space marker procedures (Prussian blue and lanthanum nitrate) were employed to determine the pathway(s) followed by water and solutes in the transpiration stream after their introduction into the xylem of small and intermediate bundles, and the effectiveness of the suberin lamellae of the bundle-sheath cells as a barrier to the movement of tracer ions (Fe³⁺ and La³⁺). Judged from the distribution of Prussian-blue crystals (insoluble, crystalline deposits resulting from the precipitation of ferric ions by ferrocyanide anions) and lanthanum deposits, water and the tracer ions moved readily from the lumina of the vessels into the apoplast (cell wall continuum) of the phloem and bundle-sheath cells via portions of vessel primary walls not bearing lignified secondary wall thickenings. Prussian blue and lanthanum deposits were abundant on the bundlesheath cell side of the bundle sheath/mesophyll interface but few occurred on that of the mesophyll, indicating that the suberin lamella is an effective barrier to apoplastic movement of both ferric and lanthanum ions. The presence of Prussian-blue crystals and lanthanum deposits in the compound middle lamella of the radial wall of the bundle-sheath cells indicates that the compound middle lamella provides an apoplastic pathway for transpirational water from the xylem to the evaporating surfaces of the mesophyll and epidermal cells.     

Quantitation of poly-β-hydroxybutyrate by fluorescence of bacteria and granules stained with Nile blue A

Summary Fluorescence from poly--hydroxybutyrate (PHB) inclusions inside Azotobacter vinelandii UWD cells stained with Nile blue A was shown to be proportional to PHB concentration. The intensity of the fluorescence was greatest in native, fluid inclusions and was the least in extracted, crystallized granules. However, isolated air-dried PHB granules also were proportionally stained with Nile blue A. The results show that Nile blue A can be used in the quantitative determination of PHB in a variety of cells.