Tensile, Flexural and Compressive Strength Studies on Calcium Oxalate Monohydrate Urinary Stone

2012 ◽  
Vol 584 ◽  
pp. 494-498
Author(s):  
Abdul Rasheed Mohamed Ali ◽  
Narayanasamy Arunai Nambi Raj
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Calcium Oxalate ◽  
Flexural Modulus ◽  
Renal Calculi ◽  
Calcium Oxalate Monohydrate ◽  
Urinary Stone ◽  
Laser Lithotripsy ◽  
X Ray Diffraction

Calcium oxalate monohydrate (COM) is the primary constituent of the majority of stones formed in the urinary tract. Mechanical properties of renal calculi dictate how a stone interact and disintegrate with mechanical forces produced by shock wave and laser lithotripsy techniques. Tensile stresses may be more effective in some instances in disrupting material because most materials are weaker in tension than compression. Urinary stone containing COM as a major component was subjected to tensile, flexural and compressive strength studies in order to understand its mechanical properties in vitro. The calculated tensile breaking strength for the urinary stone from three tests varies from 0.57 MNm-2 to 1.52 MNm-2. The flexural strength and the flexural modulus of the urinary stone were calculated as 5.17 MNm-2 and 2.22 GNm-2 respectively while the observed compressive strength was 6.11 MNm-2. The chemical composition and the crystalline nature of the stone were verified using Fourier Transform Infrared spectroscopy and X-ray diffraction.

scholarly journals In vitro mass reduction of calcium oxalate urinary calculi by some medicinal plants

2021 ◽  
Vol 27 (1) ◽  
Author(s):  
R. El Habbani ◽  
A. Lahrichi ◽  
T. Sqalli Houssaini ◽  
R. Kachkoul ◽  
M. Mohim ◽  
...  
Keyword(s):  
Medicinal Plants ◽  
Calcium Oxalate ◽  
Urinary Calculi ◽  
Calcium Oxalate Monohydrate ◽  
Urinary Stone ◽  
Positive Control ◽  
Potassium Citrate ◽  
Ammi Visnaga ◽  
Loss Of Mass

Abstract Background Calcium oxalate is the most frequent urinary stone component; it exists in three different crystalline forms. In this case, the most common is the calcium oxalate monohydrate (whewellite). However, Morocco is one of the countries that has used the traditional medicine based on natural plants to treat many diseases including urolithiasis. In this respect, the most medicinal plants used for this purpose are Herniaria hirsuta L., Opuntia ficus-indica flowers, Zea mays styles and Ammi visnaga L. seeds. The purpose of this work is to study experimentally the effectiveness of each plant on the dissolution of whewellite stones. Methods In 1 L boiled saline solution (9 g/L of NaCl), 5 g of plant extract powder has been introduced. Thereafter, the mixture was left soaked for 15 min and then filtered. Further, a specific installation that resembles the urinary circuit has been conducted in the laboratory. As a starting step, three whewellite stones are placed in contact with extract solutions for 8 weeks. Two other solutions have been used to correct the loss mass: the first one is a solution of potassium citrate of 3 mmol/L served as a positive control, and the second one is a solution of NaCl of 9 g/L without extract used as a reference point. Results After 8 weeks, the loss mass is about 54.88 ± 1.32% with Z. mays styles, 49.86 ± 1.69% with H. hirsuta L., 47.10 ± 1019% with A. visnaga L. and 44.97 ± 1.76% with flowers O. ficus-indica, while the loss of mass in the presence of witnesses solutions is 21.95 ± 0.76% for potassium citrate (C Pot) and 21.05 ± 1.07% in the case of saline solutions. Conclusion Our experiments show the effectiveness of the extracts of four plants specially for Z. mays styles. These extracts can be effective remedies in the oxalocalcic stones’ dissolution.

Impact of Pulse Mode on Dusting Effect for Holmium Laser Lithotripsy: In Vitro Evaluation with Calcium Oxalate Monohydrate Stones

Urology ◽  
2021 ◽  
Author(s):  
Nikta R. Khajeh ◽  
Kristian M. Black ◽  
Stephanie Daignault-Newton ◽  
Tim L. Hall ◽  
William W. Roberts ◽  
...  
Keyword(s):  
Calcium Oxalate ◽  
Calcium Oxalate Monohydrate ◽  
Pulse Mode ◽  
Laser Lithotripsy ◽  
Holmium Laser ◽  
In Vitro Evaluation ◽  
Holmium Laser Lithotripsy

scholarly journals Effect of Locally Available Wheat Straw Ash in Developing High Strength Concrete

2021 ◽  
pp. 19-28
Author(s):  
Muhammad Armaghan Siffat ◽  
Muhammad Ishfaq ◽  
Afaq Ahmad ◽  
Khalil Ur Rehman ◽  
Fawad Ahmad
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Wheat Straw ◽  
High Strength Concrete ◽  
High Strength ◽  
Optimum Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Strength Concrete ◽  
Straw Ash

This study is supervised to assess the characteristics of the locally available wheat straw ash (WSA) to consume as a substitute to the cement and support in enhancing the mechanical properties of concrete. Initially, after incineration at optimum temperature of 800°C for 0.5, the ash of wheat straw was made up to the desirable level of fineness by passing through it to the several grinding cycles. Subsequently, the X-ray fluorescence (XRF) along with X-ray diffraction (XRD) testing conducted on ash of wheat straw for the evaluation its pozzolanic potential. Finally, the specimens of concrete were made by consuming 10% and 20% percentages of wheat straw ash as a replacement in concrete to conclude its impact on the compressive strength of high strength concrete. The cylinders of steel of dimensions 10cm diameter x 20cm depth were acquired to evaluate the compressive strength of high strength concrete. The relative outcomes of cylinders made of wheat straw ash substitution presented the slight increase in strength values of the concrete. Ultimately, the C-100 blends and WSA aided cement blends were inspected for the rheology of WSA through FTIR spectroscopy along with Thermogravimetric technique. The conclusions authenticate the WSA potential to replace cement in the manufacturing of the high strength concrete.

A comparative study of the adsorption of amino acids on to calcium minerals found in renal calculi

2001 ◽  
Vol 101 (2) ◽  
pp. 159-168 ◽  
Author(s):  
David E. FLEMING ◽  
Wilhelm VAN BRONSWIJK ◽  
Rosemary Lyons RYALL
Keyword(s):  
Amino Acids ◽  
Calcium Oxalate ◽  
Binding Affinity ◽  
Stone Formation ◽  
Human Kidney ◽  
Renal Calculi ◽  
Calcium Oxalate Monohydrate ◽  
Carboxyglutamic Acid ◽  
Calcium Minerals ◽  
Ph Range

To assess the binding of individual amino acids to the principal calcium minerals found in human kidney stones, the adsorption of 20 amino acids on to calcium oxalate monohydrate, CaHPO4.2H2O, Ca3(PO4)2 and Ca5(PO4)3OH crystals was determined over the physiological urinary pH range (pH 5–8) in aqueous solutions. All amino acids adsorbed most strongly at pH 5, and this decreased in all cases as the pH was increased. The amino acids which adsorbed most strongly were aspartic acid, glutamic acid and γ-carboxyglutamic acid, with the last displaying the strongest affinity. All amino acids bound more avidly to calcium oxalate monohydrate than to any of the phosphate minerals. Adsorption on to CaHPO4.2H2O was generally higher than for Ca3(PO4)2 and Ca5(PO4)3OH, for which all amino acids, with the exception of γ-carboxyglutamic acid, had only a weak affinity. The binding affinity of these acids is thought to be due to their zwitterions being able to adopt conformations in which two carboxyl groups, and possibly the amino group, can interact with the mineral surface without further rotation. The strong binding affinity of di-and tri-carboxylic acids for calcium stone minerals indicates that proteins rich in these amino acids are more likely to play a functional role in stone pathogenesis than those possessing only a few such residues. These findings, as well as the preferential adsorption of the amino acids for calcium oxalate monohydrate rather than calcium phosphate minerals, have ramifications for research aimed at discovering the true role of proteins in stone formation and for potential application in the design of synthetic peptides for use in stone therapy.

Effects of hydroxyapatite content on mechanical properties and in-vitro corrosion behavior of ZK60/HA composites

2020 ◽  
Vol 111 (8) ◽  
pp. 621-631
Author(s):  
Jie Teng ◽  
Zili Xu ◽  
Jinlong Su ◽  
Yuan Li
Keyword(s):  
Mechanical Properties ◽  
Corrosion Resistance ◽  
Corrosion Behavior ◽  
Electrochemical Measurement ◽  
X Ray Diffraction ◽  
Corrosion Morphology ◽  
Hardness Tests ◽  
Zk60 Alloy ◽  
Immersion Testing

Abstract In this study, hydroxyapatite-reinforced ZK60 Mg alloybased composites were fabricated via a powder metallurgy route. The mechanical properties of these composites were studied by compressive tests and hardness tests. The in-vitro corrosion behavior was also investigated using immersion testing and electrochemical measurement. The influence of hydroxyapatite content on the mechanical properties and invitro corrosion behavior was evaluated. The microstructure and corrosion morphology were characterized by means of X-ray diffraction, optical and scanning electron microscopy. The results showed that the composite materials with 10 wt.% hydroxyapatite exhibited a better combination of mechanical strength and corrosion resistance. Compared with ZK60 alloy, the addition of 10 wt.% hydroxyapatite resulted in an increase in corrosion resistance by 38.6%.

UTILIZATION OF FLY ASH AND CONCRETE RESIDUE IN THE PRODUCTION OF GEOPOLYMER BRICKS

2017 ◽  
Vol 12 (1) ◽  
pp. 63-77 ◽  
Author(s):  
Siriporn Sirikingkaew ◽  
Nuta Supakata
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Compressive Strength ◽  
Phase Composition ◽  
Fly Ash ◽  
Industrial Waste ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

This study presents the development of geopolymer bricks synthetized from industrial waste, including fly ash mixed with concrete residue containing aluminosilicate compound. The above two ingredients are mixed according to five ratios: 100:0, 95:5, 90:10, 85:15, and 80:20. The mixture's physico-mechanical properties, in terms of water absorption and the compressive strength of the geopolymer bricks, are investigated according to the TIS 168-2546 standard. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses are used to investigate the microstructure and the elemental and phase composition of the brick specimens. The results indicate that the combination of fly ash and concrete residue represents a suitable approach to brick production, as required by the TIS 168–2546 standard.

scholarly journals Brushite cement containing gelatin: evaluation of mechanical strength and in vitro degradation

Cerâmica ◽  
2019 ◽  
Vol 65 (374) ◽  
pp. 261-266 ◽  
Author(s):  
L. P. Silva ◽  
M. D. P. Ribeiro ◽  
E. S. Trichês ◽  
M. Motisuke
Keyword(s):  
Mechanical Properties ◽  
Weight Loss ◽  
Compressive Strength ◽  
Solid Phase ◽  
Setting Time ◽  
Biological Properties ◽  
Solubility In Water ◽  
Ringer’S Solution ◽  
Weight Loss Data

Abstract Calcium phosphate cements (CPCs) are potential materials for repairing bone defects, mainly due to their excellent biocompatibility and osteoconductivity. Nevertheless, their low mechanical properties limit their usage in clinical applications. The gelatin addition may improve the mechanical and biological properties of CPCs, but their solubility in water may increase the porosity of the cement during degradation. Thus, the aim of this work was to investigate the influence of gelatin on the setting time, compressive strength and degradation rate of a brushite cement. CPCs were prepared with the addition of 0, 5, 10 and 20 wt% of gelatin powder in the solid phase of the cement. The results indicated that the setting time increased with gelatin. Furthermore, cement with 20 wt% of gelatin had an initial compressive strength of 14.1±1.8 MPa while cement without gelatin had 4.5±1.2 MPa. The weight loss, morphology and compressive strength were evaluated after degradation in Ringer’s solution. According to the weight loss data, gelatin was eliminated of samples during degradation. It was concluded that the presence of gelatin improved CPCs mechanical properties; however, as degradation in Ringer’s solution evolved, cement compressive strength decreased due to gelatin dissolution and, consequently, an increase in sample porosity.

Comparison of Urinary Crystallites from Patients with Renal Calculi with that from Healthy Subjects

2012 ◽  
Vol 554-556 ◽  
pp. 1738-1741 ◽  
Author(s):  
Zhi Yue Xia ◽  
Yi Ming Ding ◽  
Jian Ming Ouyang
Keyword(s):  
Particle Size ◽  
Zeta Potential ◽  
Calcium Oxalate ◽  
Healthy Subjects ◽  
Renal Calculi ◽  
Calcium Oxalate Monohydrate ◽  
Calcium Oxalate Dihydrate ◽  
Aggregation State ◽  
Particle Size Analyzer ◽  
Sharp Edges

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.

scholarly journals Active Phagocytosis and Diachronic Processing of Calcium Oxalate Monohydrate Crystals in an in vitro Macrophage Model

2019 ◽  
Vol 44 (5) ◽  
pp. 1014-1025
Author(s):  
Atsushi Okada ◽  
Hiromasa Aoki ◽  
Daichi Onozato ◽  
Taiki Kato ◽  
Tadahiro Hashita ◽  
...  
Keyword(s):  
Light Microscopy ◽  
Calcium Oxalate ◽  
Polarized Light ◽  
Calcium Oxalate Monohydrate ◽  
In Vitro Models ◽  
Polarized Light Microscopy ◽  
Transmission Electron ◽  
Imaging Cytometry ◽  
Acidic Organelles

Background: We previously discovered that renal macrophages (Mφs) phagocytose renal calcium oxalate monohydrate (COM) crystals. This study investigated the processing of engulfed crystals using in vitro models. Methods: J774.1 mouse Mφs were exposed to COM crystals and observed for 24 h using polarized light microscopy with/without cytochalasin B (CB), an inhibitor of phagocytosis, to confirm active crystal phagocytosis. LysoTracker and immunohistochemical staining using transmission electron microscopy for lysosomal-associated membrane protein 1 were used to confirm engulfed COM crystal uptake into lysosomes. Diachronic tracking of specific Mφs was performed to capture the entire course of engulfed COM crystal processing using polarized light microscopy. Follow-up studies of fluorescent COM (f-COM) crystals using imaging cytometry were performed in the presence and absence of nigericin to dissipate the pH gradient in acidic organelles. Results: Phagocytosis rates increased with COM density and were significantly lower in cells treated with CB (p < 0.01). We observed that engulfed crystals colocalized within lysosomes of the Mφs; moreover, diachronic observation indicated that the engulfed COM crystals were subdivided during Mφ division and eliminated by the 7th day of culture. Additionally, imaging cytometry showed that the fluorescence level of f-COM crystals in the nigericin (–) group after 48 h was significantly lower than that in the nigericin (+) group. Conclusions: This study confirmed active phagocytosis and lysosomal processing of engulfed COM crystals by Mφs. This discovery is expected to contribute to the development of future drugs that enhance the COM crystal phagocytic ability of Mφs.

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