A synchrotron study of bladder urolith architecture

2000 ◽  
Vol 15 (2) ◽  
pp. 94-100
Author(s):  
K. D. Rogers ◽  
M. W. Sperrin ◽  
E. J. MacLean

The principal aim of this study was to assess a new approach to the characterization of uroliths using synchrotron radiation. To achieve this, a detailed investigation of the crystalline nature of a human bladder urolith has been undertaken. Changes in the phase composition and crystalline mineral nature have been measured from the urolith core center to its outer surface. Data were collected using a microbeam, synchrotron probe, and image plate. Rietveld analysis has enabled us to determine that the unit cell dimensions of the majority phases (anhydrous uric acid and calcium oxalate monohydrate) are significantly greater in the core region but become progressively smaller from the outer to inner regions. The crystallites of both phases are also shown to possess significant radial orientation which varies through the urolith and reaches a maximum at a point of principal fracture. The analysis has also allowed us to study the change in average crystallite morphology; the crystallites of both phases are shown to decrease in size toward the outer parts of the urolith although this is in a nonuniform fashion. Evidence of calcium oxalate dihydrate was also found, but only within the outermost region of the urolith.

1996 ◽  
Vol 51 (5-6) ◽  
pp. 426-428 ◽  
Author(s):  
P.V. Monje ◽  
E.J. Baran

Abstract The isolation of well formed crystals of the biomineral weddellite (calcium oxalate dihydrate) from Chamaecereus silvestrii, a Cactaceae species found in the northern part of Argentina, is described. Infrared spectroscopic measurements allow an unambiguous characterization of the nature of the crystals. This is the first report of the presence of a biomineral in this plant species.


2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Houda Marouani ◽  
Salem Slayyem Al-Deyab ◽  
Mohamed Rzaigui

Single crystals of [2-CH3CH2C6H4NH3]6P6O18⋅4H2O are synthesized in aqueous solution by the interaction of cyclohexaphosphoric acid and 2-ethylaniline. This compound crystallizes in the monoclinic system with P21/c space group the unit cell dimensions are: a=16.220(4) Å, b=10.220(5) Å, c=20.328(4) Å, β=113.24(3)∘, Z=2, and V=3096.5(18) Å3. The atomic arrangement can be described by layers formed by cyclohexaphosphate anions P6O186− and water molecules connected by hydrogen bonds O–H⋯O. These inorganic layers are developed around bc planes at x=1/2 and are interconnected by the H-bonds created by ammonium groups of organic cations. All the hydrogen bonds, the van der Waals contacts and electrostatic interactions between the different entities give rise to a three-dimensional network in the structure and add stability to this compound. The thermal behaviour and the IR spectroscopic studies of this new cyclohexaphosphate are discussed.


1987 ◽  
Vol 42 (2) ◽  
pp. 89-93 ◽  
Author(s):  
Toshitsugu Oka ◽  
Toshiaki Yoshioka ◽  
Takuo Koide ◽  
Minato Takaha ◽  
Takao Sonoda

2012 ◽  
Vol 554-556 ◽  
pp. 1738-1741 ◽  
Author(s):  
Zhi Yue Xia ◽  
Yi Ming Ding ◽  
Jian Ming Ouyang

The differences between the urinary crystallites from patients with renal calculi and healthy subjects were compared using SEM, XRD, and nano-particle size analyzer, etc. These differences concern morphology, aggregation state, number, particle size, crystal phase and Zeta potential, etc. About 90% of the crystallites had the particle sizes less than 20 μm, the Zeta potential was -(113) mV, and the composition included a large proportion of calcium oxalate dihydrate (COD) crystals. By comparison, the urinary crystallites from patients with renal calculi had sharp edges and corners and exhibited significant aggregation. There were more crystallites with the size greater than 20 μm in comparison with those in healthy subjects, their Zeta potential was -(73) mV, and calcium oxalate existed mainly in the form of calcium oxalate monohydrate (COM) crystals. The above differences increased the aggregation trend of the crystallites in lithogenic urine and caused the probability of renal calculi formation to increase.


1992 ◽  
Vol 45 (11) ◽  
pp. 1933 ◽  
Author(s):  
PR Traill ◽  
AG Wedd ◽  
ERT Tiekink

The characterization of two MoVI complexes, cis -[MoO2(2-pymS)2] and cis -[MoO2(2-pyS)2] (where 2-pymSH is pyrimidine-2-thiol and 2-pySH is pyridine-2-thiol), and their reaction with Ph3P are reported. The X-ray structure of cis -[MoO2(2-pymS)2] shows the molybdenum atom to exist in a distorted octahedral geometry defined by two mutually cis oxygen atoms and two chelating 2-pymS ligands so that the two sulfur atoms occupy approximate trans positions. Crystals of cis -[MoO2(2-pymS)2] are monoclinic, space group P 21/n, with unit cell dimensions: a 9.301(3), b 12.121(2), c 11.303(3) �, β 112.62(3)�, V 1176.3 �3, Z 4. The structure was refined by a full-matrix least-squares procedure to R 0.067 for 1858 reflections with I ≥ 2.5 (I).


1990 ◽  
Vol 79 (1) ◽  
pp. 9-15 ◽  
Author(s):  
Phulwinder K. Grover ◽  
Rosemary L. Ryall ◽  
Villis R. Marshall

1. The effect of hyperuricosuria, simulated by increasing the concentration of dissolved urate, on the crystallization of calcium oxalate in human urine was examined. 2. Twenty urine samples were studied. Ten of these, designated type A, spontaneously precipitated calcium oxalate dihydrate crystals upon the addition of a solution of sodium urate solution which raised the median urate concentration from 3.1 to 7.0 mmol/l. 3. Adding dissolved urate to the remaining type B samples raised the median urate concentration from 2.2 to 6.2 mmol/l, but did not cause the precipitation of calcium oxalate. This was induced in these samples by the addition of a standard load of oxalate above an empirically determined metastable limit. 4. In the type B urine samples, the addition of urate decreased the median metastable limit from 125 to 66 μmol of oxalate, trebled the median volume of crystalline calcium oxalate deposited from 35 000 to 105 000 μm3/μl and significantly increased the overall size of the particles precipitated. Calcium oxalate monohydrate was exclusively precipitated, and the individual crystals deposited in the presence of urate were markedly smaller, more numerous, and more highly aggregated than those produced in its absence. 5. These results constitute the most convincing evidence yet obtained that hyperuricosuria may be a powerful promoter of calcium oxalate stone formation.


2007 ◽  
Vol 62 (6) ◽  
pp. 868-870 ◽  
Author(s):  
Johanna Kutuniva ◽  
Raija Oilunkaniemi ◽  
Risto S. Laitinen ◽  
Janne Asikkala ◽  
Johanna Kärkkäinen ◽  
...  

1-Butyl-2,3-dimethylimidazolium bromide {(bdmim)Br} (1) and iodide {(bdmim)I} (2) were prepared conveniently by the reaction of 1,2-dimethylimidazole and the corresponding 1-halobutane. The compounds were characterized by 1H and 13C{1H} NMR spectroscopy as well as by X-ray single crystal crystallography. 1 crystallizes in the monoclinic crystal system, space group P21/n, with Z = 4, and unit cell dimensions a = 8.588(2), b = 11.789(1), c = 10.737(2) Å, β = 91.62(3)°. Compound 2 crystallizes in the monoclinic crystal system, space group P21/c, with Z = 8, and unit cell dimensions a = 10.821(2), b = 14.221(3), c = 15.079(2) Å , β = 90.01(3)°. The lattices of the salts are built up of 1-butyl-2,3- dimethylimidazolium cations and halide anions. The cations of 1 form a double layer with the imidazolium rings stacked together due to π interactions. The Br− anions lie approximately in the plane of the imidazolium ring, and the closest interionic Br···H contacts span a range of 2.733(1) - 2.903(1) Å. Compound 2 shows no π stacking interactions. The closest interionic I···H contacts are 2.914(1) - 3.196(1) Å


2009 ◽  
Vol 2009 ◽  
pp. 1-7 ◽  
Author(s):  
Bao-Song Gui ◽  
Rong Xie ◽  
Xiu-Qiong Yao ◽  
Mei-Ru Li ◽  
Jian-Ming Ouyang

The composition and morphology of nanocrystals in urines of healthy persons and lithogenic patients were comparatively investigated by means of X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was shown that the main composition of urinary nanocrystals in healthy persons were calcium oxalate dihydrate (COD), uric acid, and ammonium magnesium phosphate (struvite). However, the main compositions of urinary nanocrystals in lithogenic patients were struvite,β-tricalcium phosphate, uric acid, COD, and calcium oxalate monohydrate (COM). According to the XRD data, the size of nanocrystals was calculated to be23∼72 nm in healthy urine and12∼118 nm in lithogenic urine by Scherer formula. TEM results showed that the nanocrystals in healthy urine were dispersive and uniform with a mean size of about 38 nm. In contrast, the nanocrystals in lithogenic urine were much aggregated with a mean size of about 55 nm. The results in this work indicated that the urinary stone formation may be prevented by diminishing the aggregation and the size differentiation of urinary nanocrystals by physical or chemical methods.


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