Les cystides à cristaux des Inocybes (Agaricales): étude histochimique et cristallographique

1992 ◽  
Vol 70 (5) ◽  
pp. 910-920 ◽  
Author(s):  
L. Waterkeyn ◽  
A. Bienfait ◽  
T. Monniez
Keyword(s):  
Electron Microscopy ◽  
Calcium Oxalate ◽  
Carboxyl Groups ◽  
Local Concentration ◽  
Monoclinic System ◽  
Excretory Function ◽  
Crystallographic Study ◽  
Crystal Sand ◽  
Aqueous Droplet ◽  
Scanning Electron

Histochemical and cristallographic studies were performed in light microscopy and scanning electron microscopy on crystal-bearing cystidia of several Inocybe spp. (Agaricales) and confirmed the excretory function of these sterile cells of the hymenium. At the apex of these bottle-like cells, the wall had an axial polysaccharidic matrix rich in carboxyl groups. It also presented an enhanced permeability and a local concentration of Ca2+. Functioning as an hydathode, the cystidium secreted, at its apex, an aqueous droplet into which twin crystals developed. In addition, crystal sand were found in the cystidium wall. These two crystalline products were calcium oxalate as confirmed with anthracene green and the Pizzolato test. A detailed crystallographic study showed that these twin crystals undoubtedly belong to the monoclinic system, i.e., the monohydrated form of the calcium oxalate or whewellite. In the case of Inocybe asterospora Quél., these grouped crystals were formed regularly by two pairs of twin crystals. The identification and localization of the Ca2+ ions have been determined with the scanning electron microscope by means of the X-emission pictures and the resulting energy dispersive X-spectrum for the latter element. Key words: Inocybe, cystidium, hydathode, calcium oxalate, whewellite.

Identification of calcium oxalate crystals in dried or fixed tobacco leaf

1984 ◽  
Vol 42 ◽  
pp. 288-289
Author(s):  
Vicki L. Baliga ◽  
Mary Ellen Counts
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Calcium Oxalate ◽  
Growth And Development ◽  
Polarized Light ◽  
Calcium Oxalate Crystals ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

Calcium is an important element in the growth and development of plants and one form of calcium is calcium oxalate. Calcium oxalate has been found in leaf seed, stem material plant tissue culture, fungi and lichen using one or more of the following methods—polarized light microscopy (PLM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction.Two methods are presented here for qualitatively estimating calcium oxalate in dried or fixed tobacco (Nicotiana) leaf from different stalk positions using PLM. SEM, coupled with energy dispersive x-ray spectrometry (EDS), and powder x-ray diffraction were used to verify that the crystals observed in the dried leaf with PLM were calcium oxalate.

scholarly journals Ovule Structure of Scotch thistle Onopordum acanthium L. (Cynareae, Asteraceae)

2016 ◽  
Vol 58 (1) ◽  
pp. 19-28 ◽  
Author(s):  
Jolanta Kolczyk ◽  
Piotr Stolarczyk ◽  
Bartosz J. Płachno
Keyword(s):  
Electron Microscopy ◽  
Calcium Oxalate ◽  
Calcium Oxalate Crystals ◽  
Polarizing Microscopy ◽  
Onopordum Acanthium ◽  
Oxalate Crystals ◽  
Transmission Electron ◽  
Mature Ovule ◽  
Vacuolated Cells ◽  
Scanning Electron

AbstractStudies concerning the ultrastructure of the periendothelial zone integumentary cells of Asteraceae species are scarce. The aim was to check whether and/or what kinds of integument modifications occur inOnopordum acanthium. Ovule structure was investigated using light microscopy, scanning electron microscopy, transmission electron microscopy and histochemistry. For visualization of calcium oxalate crystals, the polarizing microscopy was used. The periendothelial zone of integument inO. acanthiumis well developed and composed of mucilage cells near the integumentary tapetum and large, highly vacuolated cells at the chalaza and therefore they differ from other integumentary cells. The cells of this zone lack starch and protein bodies. Periendothelial zone cells do not have calcium oxalate crystals, in contrast to other integument cells. The disintegration of periendothelial zone cells was observed in a mature ovule. The general ovule structure ofO. acanthiumis similar to other members of the subfamily Carduoideae, although it is different to “Taraxacum”, “Galinsoga” and “Ratibida” ovule types.

Developmental morphology of the flower of Anthurium jenmanii: a new element in our understanding of basal Araceae

Botany ◽  
2008 ◽  
Vol 86 (1) ◽  
pp. 45-52 ◽  
Author(s):  
Denis Barabé ◽  
Christian Lacroix
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Calcium Oxalate ◽  
Floral Development ◽  
Developmental Morphology ◽  
Calcium Oxalate Crystals ◽  
Stages Of Development ◽  
Early Stages ◽  
Floral Primordia ◽  
Scanning Electron

The early stages of development of the inflorescence of Anthurium jenmanii Engl. were examined using scanning electron microscopy. The inflorescence of A. jenmanii consists of more than 100 flowers arranged in recognizable spirals. Each flower has four broad tepals enclosing four stamens that are not visible prior to anthesis. The gynoecium consists of two carpels. The floral primordia are first initiated on the lower portion of the inflorescence, they then increase in size and appear as transversely extended bulges. The two lateral tepals are the first organs to be initiated, followed shortly thereafter by the two median tepals. The two lateral stamens are initiated first, directly opposite the lateral tepals, and are followed by two median stamens initiated directly opposite the median tepals. A two-lobed stigma is clearly visible during the early stages of development of the gynoecium. On some of the young inflorescences, all floral parts were covered by extracellular calcium oxalate crystals. The release of these prismatic crystals occurs before the stamens and petals have reached maturity. The mode of floral development observed in Anthurium has similarities with that reported for Gymnostachys . However, contrary to Gymnostachys, the development of the flower of A. jenmanii is not unidirectional.

First Evidence for the Presence of Weddellite Crystallites in Opuntia ficus indica Parenchyma

2003 ◽  
Vol 58 (11-12) ◽  
pp. 812-816 ◽  
Author(s):  
Mohamed E. Malainine ◽  
Alain Dufresne ◽  
Danielle Dupeyre ◽  
Michel R. Vignon ◽  
Mostafa Mahrouz
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Calcium Oxalate ◽  
X Ray Diffraction ◽  
Experimental Protocol ◽  
Opuntia Ficus Indica ◽  
Hydration Level ◽  
X Ray ◽  
Opuntia Species ◽  
Scanning Electron

Abstract Calcium oxalate crystallites occur very often in the plants tissues and their role is still poorly known. We report here the experimental protocol leading to the isolation of two forms of calcium oxalate crystallites differing in their hydration level in the parenchymal tissues of Opuntia ficus indica (Miller). Whereas the whewellite crystallites are habitual in all Opuntia species, the weddellite form has never been isolated from these species before, which is probably due to their small size (about 1 μm). We have identified these forms using X-ray diffraction and scanning electron microscopy.

Effect of Seed Crystals of Uric Acid and Monosodium Urate on the Crystallization of Calcium Oxalate in Undiluted Human Urine in Vitro

1997 ◽  
Vol 92 (2) ◽  
pp. 205-213 ◽  
Author(s):  
Phulwinder K. Grover ◽  
Rosemary L. Ryall
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Uric Acid ◽  
Calcium Oxalate ◽  
Human Urine ◽  
Monosodium Urate ◽  
Calcium Oxalate Crystals ◽  
Seed Crystals ◽  
Oxalate Crystals ◽  
Scanning Electron

1. The aim of this study was to determine whether seed crystals of uric acid or monosodium urate promote the epitaxial deposition of calcium oxalate in undiluted human urine. The effects of seed crystals of uric acid, monosodium urate or calcium oxalate on calcium oxalate crystallization induced in pooled 24-h urine samples collected from six healthy men were determined by [14C]oxalate deposition and Coulter counter particle analysis. The precipitated crystals were examined by scanning electron microscopy. 2. Seed crystals of uric acid, monosodium urate and calcium oxalate increased the precipitated particle volume in comparison with the control containing no seeds by 13.6%, 56.8% and 206.5% respectively, whereas the deposition of [14C]oxalate in these samples relative to the control was 1.4% (P < 0.05), 5.2% (P < 0.01) and 54% (P < 0.001) respectively. The crystalline particles deposited in the presence of monosodium urate seeds were smaller than those in the control samples. Scanning electron microscopy showed that large aggregates of calcium oxalate were formed in the presence of calcium oxalate seeds, which themselves were not visible. In contrast, monosodium urate and, to a lesser extent, uric acid seeds were scattered free on the membrane surfaces and attached like barnacles upon the surface of the calcium oxalate crystals. 3. It was concluded that seed crystals of monosodium urate and uric acid do not promote calcium oxalate deposition to a physiologically significant degree in urine. Howsever, binding of monosodium urate and uric acid crystals and their subsequent enclosure within actively growing calcium oxalate crystals might occur in vivo, thereby explaining the occurrence of mixed urate/oxalate stones.

Structural and microstructural characterization of human kidney stones from eastern India using IR spectroscopy, scanning electron microscopy, thermal study and X-ray Rietveld analysis

2009 ◽  
Vol 42 (4) ◽  
pp. 629-635 ◽  
Author(s):  
Soumen Ghosh ◽  
Sharmila Basu ◽  
Santu Chakraborty ◽  
Alok K. Mukherjee
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Ir Spectroscopy ◽  
Calcium Oxalate ◽  
Kidney Stones ◽  
Human Kidney ◽  
Rietveld Analysis ◽  
Eastern India ◽  
X Ray ◽  
Scanning Electron

Structural and microstructural characterizations of eight human kidney stones (KS1–KS8) from eastern India have been carried out using IR spectroscopy, X-ray powder diffraction, scanning electron microscopy and thermogravimetric methods. An X-ray diffraction phase quantification revealed that three of the renal stones (KS1–KS3) were composed exclusively of calcium oxalate monohydrate (COM) and the remaining five (KS4–KS8) contained varying amounts of calcium oxalate dihydrate (40.1–53.0 wt%) and hydroxyapatite (1.3–17.3 wt%), in addition to the COM phase. The crystalline structure of COM (whewellite) at the atomic scale was redetermined through an X-ray powder diffraction study at room temperature using Rietveld analysis. Thermogravimetric analysis of KS1 reveals that COM (whewellite) is stable up to around 439 K, above which temperature anhydrous calcium oxalate is formed. The oxalate transforms to calcium carbonate at 751 K and finally to calcium oxide above 969 K. It should be emphasized that meaningful statistics in total number or gender specificity cannot be achieved with eight kidney stones.

Effects of inter-α-inhibitor and several of its derivatives on calcium oxalate crystallization in vitro

2000 ◽  
Vol 98 (4) ◽  
pp. 471-480 ◽  
Author(s):  
Caroline DEAN ◽  
Jerry KANELLOS ◽  
Hung PHAM ◽  
Maria GOMES ◽  
Adrian OATES ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Calcium Oxalate ◽  
Kidney Stone ◽  
Stone Formation ◽  
Calcium Oxalate Crystallization ◽  
Sds Page ◽  
Kidney Stone Formation ◽  
Scanning Electron

The bikunin peptide chain of the protease inhibitor inter-α-inhibitor (∣α∣) has been reported to be an inhibitor of calcium oxalate (CaOx) crystallization, and hence has been proposed as having a role in CaOx kidney stone formation. However, further experimental evidence is required to assess if fragments of ∣α∣ other than bikunin may play a role in the regulation of crystallization events in stone formation. The aim of the present study was to assess the effects of ∣α∣ and several of its derivatives on CaOx crystallization in a seeded inorganic system and to compare these effects with those of a known inhibitor of crystallization, prothrombin. ∣α∣ was purified from a preparation of human plasma and fragmented by alkaline hydrolysis, and two of its peptide chains, bikunin and heavy chain 1 (H1), were purified further by HPLC. Their purity was confirmed by SDS/PAGE. Using Coulter counter and [14C]oxalate analysis and scanning electron microscopy, ∣α∣, its H1 chain and bikunin from urine and from plasma were shown to be relatively weak inhibitors of CaOx crystallization in vitro at expected physiological concentrations. It was concluded that members of the ∣α∣ family may not be as important in kidney stone formation as has been generally proposed, although further studies are required before a possible role for ∣α∣ and its fragments in stone formation can be unambiguously discounted.

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