Urate Does Not Influence the Formation of Calcium Oxalate Crystals in Whole Human Urine at pH 5·3

1982 ◽  
Vol 62 (4) ◽  
pp. 421-425 ◽  
Author(s):  
P. C. Hallson ◽  
G. A. Rose ◽  
S. Sulaiman
Keyword(s):  
Calcium Oxalate ◽  
Human Urine ◽  
Opposite Effect ◽  
Crystal Formation ◽  
Calcium Oxalate Crystals ◽  
Calcium Oxalate Crystal ◽  
Quantitative Microscopy ◽  
Calcium Oxalate Stones ◽  
Oxalate Crystals

1. Samples of fresh human urine were treated with immobilized uricase to lower urate concentration. Urate was added to yield low, normal and high urate samples. 2. Each sample was rapidly evaporated at pH 5.3 to standard osmolality and the yield of calcium oxalate crystals measured either by semi-quantitative microscopy or fully quantitative radioisotope techniques. 3. Increase of urinary urate did not increase the calcium oxalate crystals formed and may even have had an opposite effect. 4. Allantoin was without significant effect upon calcium oxalate crystal formation. 5. These data provide no support for the suggestion that reducing urate concentrations in the urine may be of value in treatment of patients with calcium oxalate stones.

Calcium oxalate crystal formation in a species of Hyphoderma (basidiomycetes)

1984 ◽  
Vol 42 ◽  
pp. 320-321
Author(s):  
H. J. Arnott ◽  
K. D. Whitney
Keyword(s):  
Calcium Oxalate ◽  
Wall Material ◽  
Free Calcium ◽  
Crystal Formation ◽  
Direct Control ◽  
Calcium Oxalate Crystals ◽  
Calcium Oxalate Crystal ◽  
Fungal Cell ◽  
Oxalate Crystals ◽  
Fungal Hyphae

Calcium oxalate crystals are often found in association with fungal hyphae. In examining leaf litter samples with the use of scanning electron microscopy, Graustein et al. demonstrated that hyphae of some basidiomycetes are often encrusted with conspicuous calcium oxalate deposits and postulated that these crystals were formed when oxalate released by the fungus precipitated with free calcium ions in the environment. Studies by Arnott and Arnott and Webb, however, showed that at least some calcium oxalate crystals produced by these fungi arose within the fungal cell wall. These studies revealed that the crystals were enclosed within a thin layer of wall material during development, and it was hypothesized that the growth of the crystals is under direct control of the fungal cell.

An SEM study of raphide crystal initials in the leaves of vitis (grape)

1995 ◽  
Vol 53 ◽  
pp. 984-985
Author(s):  
H. J. Arnott ◽  
M. A. Webb ◽  
L. E. Lopez
Keyword(s):  
Calcium Oxalate ◽  
Water Soluble ◽  
Calcium Oxalate Crystals ◽  
Calcium Oxalate Crystal ◽  
Oxalate Crystals ◽  
Large Numbers ◽  
Sem Study ◽  
The Matrix ◽  
Crystal Cells ◽  
Crystal Idioblast

Many papers have been published on the structure of calcium oxalate crystals in plants, however, few deal with the early development of crystals. Large numbers of idioblastic calcium oxalate crystal cells are found in the leaves of Vitis mustangensis, V. labrusca and V. vulpina. A crystal idioblast, or raphide cell, will produce 150-300 needle-like calcium oxalate crystals within a central vacuole. Each raphide crystal is autonomous, having been produced in a separate membrane-defined crystal chamber; the idioblast''s crystal complement is collectively embedded in a water soluble glycoprotein matrix which fills the vacuole. The crystals are twins, each having a pointed and a bidentate end (Fig 1); when mature they are about 0.5-1.2 μn in diameter and 30-70 μm in length. Crystal bundles, i.e., crystals and their matrix, can be isolated from leaves using 100% ETOH. If the bundles are treated with H2O the matrix surrounding the crystals rapidly disperses.

scholarly journals Effect of Dolichos biflorus Seeds Based Functional Beverage on In Vitro Calcium Oxalate Crystallization in Human Urine

2021 ◽  
Vol 12 (5) ◽  
pp. 5836-5844
Keyword(s):  
Antioxidant Activity ◽  
Calcium Oxalate ◽  
Human Urine ◽  
Crystallization Process ◽  
Radical Scavenging ◽  
Scavenging Activity ◽  
Calcium Oxalate Crystals ◽  
Dolichos Biflorus ◽  
Oxalate Crystals

Calcium oxalate is the most common type of urolithiasis. The crystallization process includes nucleation, growth, and the aggregation of crystals. This study has used Dolichos biflorus seeds as a functional beverage to explore the role of its bioactive substances on the crystallization process of calcium oxalate in managing urolithiasis. A human urine model of in vitro calcium oxalate crystals was used in the study. Phytochemical screening of Functional beverage of Dolichos biflorus seeds was performed, and antioxidant activity was evaluated by measuring DPPH radical-scavenging activity, reducing power assay, and Hydrogen peroxide scavenging activity. Functional beverage of Dolichos biflorus seeds inhibited crystallization process by reducing aggregation of calcium oxalate crystals. The reduction in crystals aggregation helps prevent urolithiasis by keeping the crystals dispersed in the urine, controlling their size, and facilitating expulsion from the urinary tract. The results showed that the Functional beverage of Dolichos biflorus seeds has a significant quantity of flavonoids, glycosides, etc., and also possesses a significant antioxidant activity as evaluated by employing different antioxidant assays. Therefore, our findings suggested that the functional beverage of Dolichos biflorus seeds exhibited antiurolithiatic activity through inhibition of the crystallization process of the calcium oxalate process and significant antioxidant potential.

CYSTINE: A PROMOTER OF THE GROWTH AND AGGREGATION OF CALCIUM OXALATE CRYSTALS IN NORMAL UNDILUTED HUMAN URINE

2002 ◽  
Vol 167 (1) ◽  
pp. 317-321 ◽  
Author(s):  
MARIA C. MARTINS ◽  
ANTHONY A. MEYERS ◽  
NATALIE A. WHALLEY ◽  
ALLEN L. RODGERS
Keyword(s):  
Calcium Oxalate ◽  
Human Urine ◽  
Calcium Oxalate Crystals ◽  
Oxalate Crystals

Hydroxycitric Acid Inhibits Renal Calcium Oxalate Deposition by Reducing Oxidative Stress and Inflammation

2020 ◽  
Vol 20 (7) ◽  
pp. 527-535 ◽  
Author(s):  
Xiao Liu ◽  
Peng Yuan ◽  
Xifeng Sun ◽  
Zhiqiang Chen
Keyword(s):  
Oxidative Stress ◽  
Mouse Model ◽  
Calcium Oxalate ◽  
Tubular Injury ◽  
Calcium Oxalate Crystals ◽  
Calcium Oxalate Crystal ◽  
Crystal Deposition ◽  
Qrt Pcr ◽  
Hydroxycitric Acid ◽  
Oxalate Crystals

Objective: The study aimed to evaluate the preventive effects of hydroxycitric acid（HCA） for stone formation in the glyoxylate-induced mouse model. Materials and methods: Male C57BL/6J mice were divided into a control group, glyoxylate(GOX) 100 mg/kg group, a GOX+HCA 100 mg/kg group, and a GOX+HCA 200 mg/kg group. Blood samples and kidney samples were collected on the eighth day of the experiment. We used Pizzolato staining and a polarized light microscope to examine crystal formation and evaluated oxidative stress via the levels of malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px). Quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) was used to detect the expression of monocyte chemotactic protein-1(MCP-1), nuclear factor-kappa B (NF κ B), interleukin-1 β (IL-1 β) and interleukin-6 (IL-6) messenger RNA (mRNA). The expression of osteopontin (OPN) and a cluster of differentiation-44(CD44) were detected by immunohistochemistry and qRT-PCR. In addition, periodic acid Schiff (PAS) staining and TUNEL assay were used to evaluate renal tubular injury and apoptosis. Results: HCA treatment could reduce markers of renal impairment (Blood Urea Nitrogen and serum creatinine). There was significantly less calcium oxalate crystal deposition in mice treated with HCA. Calcium oxalate crystals induced the production of reactive oxygen species and reduced the activity of antioxidant defense enzymes. HCA attenuated oxidative stress induced by calcium oxalate crystallization. HCA had inhibitory effects on calcium oxalate-induced inflammatory cytokines, such as MCP-1, IL- 1 β, and IL-6. In addition, HCA alleviated tubular injury and apoptosis caused by calcium oxalate crystals. Conclusion: HCA inhibits renal injury and calcium oxalate crystal deposition in the glyoxylate-induced mouse model through antioxidation and anti-inflammation.

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.

Effects of Human Urine on Aggregation of Calcium Oxalate Crystals

1986 ◽  
Vol 135 (1) ◽  
pp. 69-71 ◽  
Author(s):  
Kurt E. Springmann ◽  
George W. Drach ◽  
Beth Gottung ◽  
Alan D. Randolph
Keyword(s):  
Calcium Oxalate ◽  
Human Urine ◽  
Calcium Oxalate Crystals ◽  
Oxalate Crystals
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