scholarly journals Formation Mechanism of Magnesium Ammonium Phosphate Stones: A Component Analysis of Urinary Nanocrystallites

2015 ◽  
Vol 2015 ◽  
pp. 1-9
Author(s):  
Xin-Yuan Sun ◽  
Jian-Ming Ouyang ◽  
Feng-Xin Wang ◽  
Yu-Shan Xie

The components of urinary nanocrystallites in patients with magnesium ammonium phosphate (MAP) stones were analyzed by X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectrometer, high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), fast Fourier transformation (FFT), and energy-dispersive X-ray spectroscopy (EDS). The main components of the stones were MAP hexahydrate (MAP·6H2O), magnesium hydrogen phosphate trihydrate (MgHPO4·3H2O), and a small amount of calcium phosphate (CaP), while the main components of urinary nanocrystallites were MgHPO4·3H2O, CaP, and MAP monohydrate (MAP·H2O). MAP·H2O induced the formation of MAP stones as seed crystals. MgHPO4·3H2O was accompanied by the appearance of MAP·6H2O. The formation mechanism of MAP stones and influencing factors were discussed on the basis of the components of urine nanocrystallites. A model diagram of MAP stone formation was also put forward based on the results. Formation of MAP stones was closely related to the presence of high amounts of MAP crystallites in urine. Urinary crystallite condition and changes in urine components could indicate the activity of stone diseases.

1991 ◽  
Vol 37 (12) ◽  
pp. 978-983 ◽  
Author(s):  
Berlin Nelson ◽  
James Struble ◽  
Gregory McCarthy

A strain of Bacillus pumilus, isolated from the soilborne sclerotia of a fungus, produced crystals of the mineral struvite (magnesium ammonium phosphate hexahydrate) on Difco nutrient agar and a yeast extract agar containing magnesium sulphate and potassium phosphate. Crystals were macroscopically observed after 6–20 days of bacterial growth and reached a maximum size of 3 × 0.5 mm. Crystals were identified by X-ray powder diffractometry. These findings support the hypothesis that bacteria are involved in the biogenic formation of struvite in nature. Key words: struvite, magnesium ammonium phosphate hexahydrate, Bacillus pumilus, biomineral.


1972 ◽  
Vol 42 (2) ◽  
pp. 197-207 ◽  
Author(s):  
D. Fraser ◽  
R. G. G. Russell ◽  
Ortrun Pohler ◽  
W. G. Robertson ◽  
H. Fleisch

1. Bladder stones composed of calcium hydrogen phosphate dihydrate, calcium oxalate mono- and di-hydrate and magnesium ammonium phosphate hexahydrate (struvite) were successfully induced in rats by various dietary manipulations and by implanting zinc pellets in the bladder. 2. The effect of a diphosphonate, disodium ethane-1-hydroxy-1,1-diphosphonate (EHDP), given in the drinking water at concentrations of 0·0025, 0·05 and 0·5% (w/v), on the size and composition of these stones was examined. 3. All the concentrations of EHDP decreased the weight of the calcium oxalate calculi. In contrast, only the highest concentration of EHDP inhibited calcium hydrogen phosphate stone formation and the magnesium ammonium phosphate stones were unaffected. 4. The difference between the effects on calcium oxalate and magnesium ammonium phosphate stones is consistent with the finding that EHDP inhibited the precipitation of calcium oxalate from solution in vitro but had only a slight effect on magnesium ammonium phosphate precipitation. 5. It is suggested that EHDP might be of use in the prevention of some types of urinary stones in man.


2008 ◽  
Vol 8 (1) ◽  
pp. 335-339 ◽  
Author(s):  
Satyendra Singh ◽  
S. B. Krupanidhi

Multiferroic BiFeO3 (BFO) nanotubes have been successfully fabricated by the modified sol–gel method within the nanochannels of porous anodic aluminum oxide (AAO) templates. The morphology, structure and composition of the nanotubes were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), selected-area electron diffraction (SAED), high resolution TEM, (HRTEM) and energy-dispersive X-ray spectroscopy (EDX). Postannealed (650 °C for 1 h), BFO nanotubes were polycrystalline and X-ray diffraction study revealed that they are of the rhomohedrally distorted perovskite crystal structure. The results of SEM and TEM revealed that BFO nanotubes possessed a uniform length (up to 60 μm) and diameter (about 200 nm), which were controlled by the thickness and the pore diameter of the applied AAO template, respectively and the thickness of the wall of the BFO nanotube was about 15 nm. Y-junctions in the BFO nanotubes were observed. EDX analysis demonstrated that stoichiometric BiFeO3 was formed. HRTEM analysis confirmed that the obtained BFO nanotubes made up of nanoparticles (3–6 nm). The possible formation mechanism of BFO nanotubes was discussed.


2004 ◽  
Vol 72 (1) ◽  
pp. 66-75 ◽  
Author(s):  
Xin Li ◽  
C. Virginia Lockatell ◽  
David E. Johnson ◽  
M. Chelsea Lane ◽  
John W. Warren ◽  
...  

ABSTRACT Proteus mirabilis commonly infects the complicated urinary tract and is associated with urolithiasis. Stone formation is caused by bacterial urease, which hydrolyzes urea to ammonia, causing local pH to rise, and leads to the subsequent precipitation of magnesium ammonium phosphate (struvite) and calcium phosphate (apatite) crystals. To prevent these infections, we vaccinated CBA mice with formalin-killed bacteria or purified mannose-resistant, Proteus-like (MR/P) fimbriae, a surface antigen expressed by P. mirabilis during experimental urinary tract infection, via four routes of immunization: subcutaneous, intranasal, transurethral, and oral. We assessed the efficacy of vaccination using the CBA mouse model of ascending urinary tract infection. Subcutaneous or intranasal immunization with formalin-killed bacteria and intranasal or transurethral immunization with purified MR/P fimbriae significantly protected CBA mice from ascending urinary tract infection by P. mirabilis (P < 0.05). To investigate the potential of MrpH, the MR/P fimbrial tip adhesin, as a vaccine, the mature MrpH peptide (residues 23 to 275, excluding the signal peptide), and the N-terminal receptor-binding domain of MrpH (residues 23 to 157) were overexpressed as C-terminal fusions to maltose-binding protein (MBP) and purified on amylose resins. Intranasal immunization of CBA mice with MBP-MrpH (residues 23 to 157) conferred effective protection against urinary tract infection by P. mirabilis (P < 0.002).


2009 ◽  
Vol 59 (12) ◽  
Author(s):  
Claudia Maria Simonescu ◽  
Valentin Serban Teodorescu ◽  
Camelia Capatina

This paper presents the obtaining of copper sulfide CuS (covelite) from Cu(CH3COO)2.H2O and thioacetamide (TAA) system. The reaction was conducted in presence or absence of sodium-bis(2-ethylhexyl) sulfosuccinate (Na-AOT). The effects of various reaction parameters on the size and on the shape of nanoparticles have been examined. CuS obtained was characterized by X ray diffraction, IR spectroscopy, TEM � transmission electron microscopy and SAED selected area electron diffraction. The influence of surfactant to the shape and size of CuS (covellite) nanocrystals was established. The size of the nanocrystals varied from 10-60 nm depending on the reaction conditions such as quantity of surfactant.


2013 ◽  
Vol 2013 ◽  
pp. 1-3 ◽  
Author(s):  
Selcuk Sarikaya ◽  
Berkan Resorlu ◽  
Ekrem Ozyuvali ◽  
Omer Faruk Bozkurt ◽  
Ural Oguz ◽  
...  

A 28-year old man presented with left flank pain and dysuria. Plain abdominal film and computed tomography showed a left giant ureteral stone measuring 11.5 cm causing ureteral obstruction and other stones 2.5 cm in size in the lower pole of ipsilateral kidney and 7 mm in size in distal part of right ureter. A left ureterolithotomy was performed and then a double J stent was inserted into the ureter. The patient was discharged from the hospital 4 days postoperatively with no complications. Stone analysis was consistent with magnesium ammonium phosphate and calcium oxalate. Underlying anatomic or metabolic abnormalities were not detected. One month after surgery, right ureteral stone passed spontaneously, left renal stone moved to distal ureter, and it was removed by ureterolithotomy. Control intravenous urography and cystography demonstrated unobstructed bilateral ureter and the absence of vesicoureteral reflux.


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