Calcium Oxalate Formation Research Articles

Stone Formation Features in the Kidney of Residents in the South Region of Kyrgyzstan

Kidney stone disease (KSD), otherwise urolithiasis, is one of the most common and frequent diseases and occurs most often in patients of working age. With “urolithiasis” there is a metabolic disorder characterized by the presence of stones in the kidneys and urinary tract. Formation of kidney stones in residents of southern region in Kyrgyzstan has not been studied. Research objectives: determination of stone formation features in the kidney of patients in the southern region of Kyrgyzstan. Research materials and methods: a literary review of urolithiasis (KSD) of the kidneys and identification of stone formation features. Research results: kidney stone formation is a complex physical and chemical process, accompanied by growth, aggregation and retention of urinary stone in parts of tubular cells. Conclusions: formation of calcium oxalate and uric acid stones is associated with various metabolic processes in the body. Urinary calculi are formed as a result of a series of sequence of stages.

Retrospective analysis of 131 feline uroliths from the Republic of Ireland and Northern Ireland (2010-2020)

BackgroundThe proportions of different urolith types have not been investigated in cats from the Republic of Ireland (ROI) and Northern Ireland (NI) previously. The objective of this study was to investigate the proportions of different feline urolith types submitted to Minnesota Urolith Center from the ROI and NI from 2010 to 2020. An additional aim of this study was to identify potential risk factors associated with each urolith type in cats in this geographic area.ResultsOne hundred and thirty-one uroliths were submitted for the studied period with 44.3% being struvite, 43.5% calcium oxalate and 7.6% compound. Only 11 uroliths were submitted in the first 4 years. The number of submissions increased after 2015, peaking in 2019 with 25 submissions. Due to low numbers no conclusions could be made about changes in incidence of urolith types over time. Cats ≤7 years of age were significantly more likely to be diagnosed with struvite uroliths (OR, 2.87 [1.37-6.06]; p = 0.007) while cats ≥7 years of age with calcium oxalate uroliths (OR, 2.67, [1.29-5.37], p = 0.004).ConclusionsThis is the first epidemiologic study of urolithiasis from cats in the ROI and NI. The most prevalent types of uroliths in our study population were struvite and calcium oxalate. Due to the low number of urolith submissions, changes in the incidence of different uroliths could not be accurately determined. Increasing age was associated with calcium oxalate formation while younger cats were more commonly diagnosed with struvite urolithiasis which can be medically dissolved. Therefore, urolith dissolution is more likely to be successful in young cats than older cats.

Synergistic inhibition of calcium oxalate crystal formation and synergistic protection of HK-2 cells from crystal damage by sulfated Laminarin polysaccharide and potassium citrate.

Objective: The first objective is to study the synergistic inhibition of calcium oxalate (CaOx) formation by Laminarin polysaccharides (DLP and SDLP, before and after sulfation) and potassium citrate (K3cit) and determine the synergistic protection of renal epithelial cells (HK-2 cells) caused by CaOx crystal damage. The second objective is to explore new ways to prevent and treat kidney stones. Methods: The CaOx crystals regulated by five additives (K3cit group, DLP group, SDLP group, DLP-K3cit synergistic group and SDLP-K3cit synergistic group) were characterized by FT-IR, XRD, SEM, zeta potential, ICP, and TGA. The protective effect of each additive group on HK-2 cells damaged by nano-calcium oxalate monohydrate (nano-COM) was compared by detecting cell viability, the cell reactive oxygen species level, the cell survival rate, and mitochondrial membrane potential. Results: When DLP or SDLP acted synergically with K3cit, the synergistic group induced the same amount of COD at a lower concentration or more COD formation at the same concentration, highlighting the synergistic enhancement effect of 1 + 1 > 2. At 0.3 g L-1, the COD contents induced by DLP, SDLP, K3cit, DLP-K3cit, and SDLP-K3cit synergistic groups were 20.3%, 75.8%, 75.4%, 87.3%, and 100%, respectively. The synergistic group increased the concentration of soluble Ca2+ ions in the supernatant, increased the absolute value of the zeta potential on the surface of CaOx crystals, and inhibited the aggregation among the crystals. TGA and DTG analyses established the adsorption of polysaccharides in the crystals. Cell experiments showed the ability of the synergistic group to significantly inhibit the damage of nano-COM crystals on HK-2 cells, reduce the level of reactive oxygen species and mortality, and improve cell viability and the mitochondrial membrane potential. Conclusions: The synergistic group can more effectively induce COD formation and cell protection than the standalone polysaccharide group or K3cit group. The synergistic groups, especially SDLP-K3cit, may be a potential drug for inhibiting the formation of CaOx kidney stones.

The effects of salt-loss soda residue and oxalate acid on property and structure of fly ash-based geopolymer

When industrial solid waste soda residue (SR) is subjected to water erosion, certain soluble salts are lost, which influences the reuse of SR in construction materials. This research studies the possibility of using salt-loss soda residue (SLSR) in fly ash (FA)-based geopolymers activated by sodium hydroxide solution (NS). To achieve a wider application, the SR and SLSR were proposed with an oxalic acid (OA) treatment. Fluidity, electrical conductivity, and densitywere assessed to examine the effects of SLSR and OA on fresh and hardened characteristics. In addition, flexural and compressive strengths, as well as drying shrinkages, were tested to investigate the role of SLSR and OA. Furthermore, X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), and Fourier Transform Infrared Spectroscopy (FTIR) tests were carried out to evaluate the mineralogy, morphology, and products. Thermal stability was further evaluated using Thermo-Gravimetric and Differential Thermal Synchronous Thermal Analysis Spectrometer (TG-DSC) tests. The results show that SLSR and OA can be used to synthesize FA-based geopolymers at room temperature. When proper OA is introduced, SLSR contributes to higher compressive strength, improved drying shrinkage resistance, and increased thermal stability of FA-based geopolymers than SR due to the loss of soluble salts and the formation of calcium oxalate in the matrix. Furthermore, it is revealed that the structure of hardened paste (V4) prepared with SLSR, FA, and OA is composed of chemical CSH and (N, C)-ASH gels together with physically filled particles (such as calcite, calcium oxalate, sodium oxalate, and unreacted glass microsphere). The research findings give guidance for promoting the preparation of SLSR products and the utilization of organic calcium sources in geopolymer.

Effect of oxalic acid pretreatment on the mechanical properties and microstructure of phosphogypsum

In China, the amount of phosphogypsum (PG) accumulated has been increasing rapidly with the development of the phosphate fertilizer industry. PG exists mainly in the form of dihydrate gypsum, which can replace natural gypsum to produce hemihydrate gypsum and is used in the building materials industry. However, it contains impurities, such as phosphate, fluoride, sulfate, and natural radioactive elements, which limit its application and seriously pollute the surrounding environment. To promote the application of PG, it is crucial to understand how pretreatment affects the properties of hemihydrate phosphogypsum (HPG). In this research, the mechanical properties and microstructure of HPG after pretreatment was investigated for improving the reuse of PG as a promising resource. The harmful phosphorus impurity in PG was efficiently removed with different concentrations of by H2C2O4. Then the hydration process and the hardening characteristics of HPG were studied in detail. The findings indicate that H2C2O4 alters the particle characteristics of HPG and has an impact on hemihydrate gypsum dissolution and dihydrate gypsum precipitation. According to studies, small amounts of H2C2O4 can remove impurities, promoting hydration and enhancing strength by opening the closed orifice of HPG, which would promote the dissolution of HPG and alter the morphology of gypsum from a tiny crystal to a thickened columnar structure. However, the addition of excessive H2C2O4 impacts the compression strength of HPG plaster and reduces the rehydration of HPG due to the formation of calcium oxalate on the gypsum crystal surface. These new findings may give insight into how H2C2O4 affects the performance of HPG. Therefore, to ensure the efficient utilization of PG, quality stabilization and improvement are crucial.

Trace organic compounds in oxalate rock accretions from the Lower Pecos Canyonlands of southwestern Texas

AbstractCalcium oxalate‐rich rock coatings occur worldwide and commonly occur associated with prehistoric rock paintings. Radiocarbon dates of oxalates that cover or encapsulate rock paints have become the primary strategy for establishing chronologies of these artifacts. It is also apparent that oxalate films form episodically and are governed by particular climate conditions and thus could serve as a paleoclimate proxy. However, the mechanism(s) by which these coatings form remains unresolved. Here, we report on the trace organic composition of oxalate‐coating samples from the Lower Pecos Canyonlands in southwestern Texas. The samples contained a suite of dicarboxylic acids that are similar to the organic composition established for atmospheric aerosols. The predominant organic species in aerosols is oxalic acid, which reacts with calcium to form calcium oxalate. This suggests that aerosols could be a mechanism for the production of naturally occurring calcium oxalate on rock surfaces.

Efficacy of chlorogenic acid against ethylene glycol-induced renal stone model: The role of NFKB-RUNX2-AP1-OSTERIX signaling pathway

Background and objectiveRenal tissue injuries by free radicals are an essential reason in pathogenesis of urinary tract stones. Ethylene glycol is one of the toxic agents which can causes to the increases in biosynthesis of reactive oxygen species and oxidative stress condition. Natural antioxidants have been reported to protective efficacy against renal stones formation. Accordingly, the aim of the current experiment was to identify the renal protective effect of chlorogenic acid as a well-prominent antioxidant on ethylene glycol-induced renal stone model targeting the NFKB-RUNX2-AP1-OSTERIX signaling pathway. Materials and methodsRenal stones model were established by ethylene glycol (Percent: 0.75) within the daily drinking water for rats. Treatment groups received cystone (750 mg/kg) and chlorogenic acid (100, 200, and 400 mg/kg, day: 15th to 28th, gavage). After 4 weeks, the renal function parameters (calcium, uric acid, creatinine, total protein, oxalate, and citrate) in plasma, urine, and renal tissue were measured. Moreover, oxidative stress factors and gene expression of NFKB, RUNX2, AP1, and OSTERIX were also evaluated. ResultsThe results showed improved renal function in chlorogenic acid-treated groups. The total proteins and creatinine excretion were decreased. Also the gene expression of oxidative stress pathway (NFKB-RUNX2-AP1-OSTERIX) were decreased which caused to increases of antioxidant enzymes. Conclusionsthe antioxidant activity increases by chlorogenic acid treatment may have a critical role in prevention of calcium oxalate formation via inhibition of the NFKB-RUNX2-AP1-OSTERIX signaling pathway.

Evaluation Of Antiurolithiatic Activity Of Methanolic Seed Extracts Of Persea Americana Against Calcium Oxalate Induced Urolithiasis In Rats

Objective: Persea Americana methanolic seed extracts are considered for the present study to access its efficacy, urolithiasis is inducedby administering the male rats with calcium oxalate.Methods: Calcium oxalate urolithiasis is induced in male rats by means of hyperoxaluria model by administering ethylene glycol of0.75% v/v, with 1% w/v ammonium chloride supplemented in drinking water for 3 days followed by 0.75% v/v of ethylene glycol for25 days. The PAMSE is administered to urolithiasis induced test group at dose of 150mg/kg respectively for 28 days.Results: As anticipated after 28 days the calcium oxalate is deposited significantly in the kidney which is associated with the increaseof Urinary oxalate, Urine calcium & magnesium levels, serum uric acid, creatinine in urolithiasis control groups. ACP, ALP, AST &ALT well known biochemical parameters are seen to be increased with decreased level of LDH assessed using kidney homogenate,copiously confirming the induction of urolithiasis , its promising to know that the PAMSE intubation to the test group daily decreasedthe quantity of formation of calcium oxalate and all the biochemical changes induced by urolithiasis is reverted.Conclusion: Results from this study shows that PAMSE is effective inhibitor of crystallization of calcium oxalate comparable to thestandard Cystone in dose dependent mode. Therefore indicating PAMSE’s significant antiurolithiatic activity.

Study of Steel Slag Eroded by Oxalic Acid and Recovery of Leachate

The effective resource utilization of steel slag from bulk solid waste can achieve good social, environmental and economic benefits. In order to restrain the volume expansion of steel slag and apply it as a building material, in this work, oxalic acid was used for the treatment of steel slag, and the mechanism of oxalic acid restraining the expansion of steel slag was explored. This study recovered the main metal ions in steel slag while restraining its volume expansion. The volume stability of the eroded steel slag and the phase composition, microstructure, roughness and pore size distribution of the steel slag after oxalic acid erosion were investigated. The hydration process of the steel slag was characterized using the pH value, the ion distribution of the leachate was measured, and the leachate was recovered via ultraviolet catalysis and evaporation crystallization. The results showed that a large number of calcium and iron minerals in the steel slag reacted with adipic acid to form calcium oxalate, which precipitated on the surface and opened pores in the steel slag during the process of adipic acid erosion, which improved the compactness of the steel slag’s surface and improved the volume stability of the steel slag. After erosion, the surface roughness, specific surface area and porosity of the steel slag decreased, and the average pore diameter (μm) decreased from 1.717 to 0.208. In addition, the pH value was stable at approximately 7.3 over long-term interaction with water. The leachate was mainly composed of iron, calcium and silicon ions, accounting for 35.43%, 17.17% and 17.05%, respectively, which were recovered by ethanol and ammonia to obtain calcium oxalate, ferrous oxalate, ammonium oxalate and a metal hydroxide. The hydration activity of the steel slag treated with oxalic acid decreased and the volume expansibility of the steel slag was effectively restrained. The expansion rate of the steel slag decreased from 3.59% to 1.69% and the volume stability of the steel slag improved. The leachate recovery efficiency was high and was close to 100%. The utilization of steel slag as a resource was realized and the environmental problems caused by the steel slag were effectively solved.

PSXI-2 Circulating Mirnas as non-Invasive Biomarkers of Chronic Kidney Disease and Calcium Oxalate Uroliths in Felines

Abstract Chronic kidney disease (CKD), characterized by progressive loss of kidney function, is a major cause of mortality in cats. Another complication is the formation of calcium oxalate (CaOx) uroliths in the bladder and kidneys of cats, where inflammation has a role in its pathogenesis. MicroRNAs (miRNAs) are small non-coding RNAs which bind to the target mRNA to reduce its function. Depending on the target mRNA, they regulate transcription of several pro-inflammatory genes. We assessed the expression profiles of circulating miRNAs in blood, collected at the natural end-of-life in colony cats, in a retrospective study, in healthy (n=10; 5.9-16 yr), CaOx (n=10, 8.6-13.4 yr), and CKD (n=10; 8.3-15.4 yr). Circulating concentrations of creatinine, symmetric dimethylarginine, and blood urea nitrogen were significantly greater in CaOx and CKD cats compared with controls, indicating kidney dysfunction. Expression of miRNAs, measured by qRT-PCR, was analyzed using the ΔΔCt method and normalized to U6. There was a significant upregulation of miR-155 in CaOx stone formers compared with controls (p< 0.05). miR-155 is increased in the serum and urine of human patients with nephrolithiasis. miR-155 can also promote oxalate-induced renal oxidative stress by suppressing MGP expression. In humans, miR-155 concentrations are negatively correlated with cytokines including IL-1β, IL-6, and TNF-α, suggesting the involvement of inflammation in nephrolithiasis. However, miR-155 was downregulated in CKD compared with controls. miR-16 was also downregulated in CKD cats. Consistent with this, there is downregulation of both the miRNAs in human patients with Stage 4 CKD. Further, miRNAs downregulated in CaOx, but not in CKD, included miR-17, miR-19b, miR-27a, and miR-27b, whereas let-7a, miR-15a, miR-16, miR-29b, and miR-200a were downregulated only in CKD cats. Taken together, the profile of circulating miRNAs in CaOx and CKD cats may serve as important biomarkers in the initiation and progression of renal dysfunction in cats.

Nephrolithiasis management and outcomes in pediatric patients with limited mobility

Pediatric patients with limited lower extremity mobility may be at increased risk of developing nephrolithiasis due to bone mineral metabolic derangements. This study sought to assess whether nephrolithiasis management and related outcomes differ between ambulatory versus non-ambulatory pediatric patients. This was a retrospective review of ambulatory and non-ambulatory pediatric patients with nephrolithiasis from 2010 to 2021 from a single tertiary care center. Demographics, surgical history, stone compositions, and 24-h urine data were reviewed. Adjusted logistic and linear regression models were utilized to assess whether mobility status was associated with nephrolithiasis-related management and outcomes, including: age at first stone; requiring surgical intervention for stones; number of surgeries; stone compositions; urine culture results; and completion of 24-h urine studies. Among 339 pediatric patients with nephrolithiasis, 67 (19.8%) were non-ambulatory. In adjusted analyses, non-ambulatory patients had 3.24 times greater odds of requiring surgical intervention for stones (95% CI: 1.93-6.84; p<0.0001); among those who required surgery, non-ambulatory patients required an average of 0.82 more surgical interventions (95% CI: 0.35-1.30; p=0.0008) than ambulatory patients. Additionally, non-ambulatory patients had 5.28 times greater odds of having a positive urine culture at the time of surgery (95% CI: 2.35-14.08; p=0.0001) and were significantly less likely to undergo 24-h urine studies (OR: 0.35; 95% CI: 0.15-0.83; p=0.02). Stone composition significantly varied by mobility status, with non-ambulatory patients being significantly more likely to form calcium apatite (OR: 5.1; 95% CI: 2.18-11.93; p=0.0002) or struvite (OR 3.72; 95% CI: 1.18-11.74; p=0.03) stones, and significantly less likely to form calcium oxalate stones (OR: 0.19; 95 CI: 0.08-0.47; p=0.0003). Among all patients, age at first stone occurred at a median age of 13.4 years (IQR: 8.2-16.4) and did not significantly differ by mobility status (p=0.92). Patients with limited mobility required surgery for nephrolithiasis at significantly higher rates and had different stone compositions than ambulatory patients. Obtaining a 24-h urine study in patients with comorbidities affecting ambulation was uncommon, compared to ambulatory patients. Similarly to ambulatory patients, pediatric patients with limited mobility who develop nephrolithiasis tend to first present with stones in early adolescence.

Fulvic Acid from Chestnut Forest as an Added Qualities to Spring Water: Isolation and Characterization from Fiuggi Waters

The aquifer of “mineral” water, historically known for its curative properties, is an identifying characteristic of the Anticolana valley. This area hosted a coppice chestnut forest for a long time. Under the forest, there is an important aquifer, historically renowned and widely recognized for preventing renal stone formation and or facilitating their expulsion. This mineral water pre- vents the formation of calcium oxalate and phosphate crystals in the kidney and promotes their dissolutions through soluble calcium complexes. The forest environment soil is particularly rich in humification products owing to the interaction of the rainwater–litter–soil system. The fulvic fraction is soluble in water under all pH conditions and enriches the water basin. We aimed to test these hypotheses and assess how the coppice chestnut forest is involved in fulvic acid production. Fulvic fractions isolated and purified from soil samples and mineral water (550 μg L−1) were analyzed by GC-MS, FTIR, and NMR. Data from different sources were compared, showing sufficient similarities to state that the fulvic acids isolated from the water come from the processes that take place between the stems and the chestnut litter. The chestnut forest provides enrichment to water quality, which is a distinctive piece of information in defining water enhancement strategies, establishing soil management and designating sustainable forest management.

Electrocrystallization of Calcium Oxalate on Electrospun PCL Fibers Loaded with Phytic Acid as a Template.

Crystallization occurs widely in living organisms where different organs could associate with the calcification process, such as the formation of calcium oxalate (CaOx) calculi in the urinary tract. However, the pathogenesis and the role of an inhibitor in the pathological processes involved in urolithiasis is poorly understood. Therefore, the use of phytic acid (PA) as an inhibitor for the organic fibrillar matrix is a novel approach to inhibit the formation of pathological CaOx crystals. Herein, electrospun polymer fiber meshes of polycaprolactone (PCL) with random (R) and aligned (A) fiber orientations containing PA were prepared by electrospinning, and their role as a 3D organic template in in vitro CaOx crystallization was investigated. CaOx crystals were generated on conductive tin indium oxide (ITO)-modified glass with R-PCL and A-PCL fibers in the presence of PA through an electrocrystallization (EC) procedure. This study provides a simple electrochemical approach to evaluate the role of PA as an inhibitor in the nucleation of pathological CaOx crystals. The resulting CaOx crystals were analyzed by chrono-potentiometry, optical microscopy (OM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). We found that PA and the fiber orientations are key factors in the nucleation and crystal growth of CaOx, achieving the stabilization of healthy CaOx crystal and the inhibition of the pathological crystal form.

Vinegar reduced renal calcium oxalate stones by regulating acetate metabolism in gut microbiota and crystal adhesion in rats.

Urolithiasis is a common urologic disease. Higher consumption of vinegar was associated with a lower risk of urolithiasis. Recent studies reported that disorder of gut microbiota and injury of the tight junction of renal tubular epithelial cells were associated with the formation of renal calcium oxalate (CaOx) stones. We aimed to explore the mechanism of vinegar reduced renal CaOx stone formation by regulating gut microbiota and the tight junction of renal tubular epithelial cells. Thirty Sprague-Dawley rats were randomly allocated to control group, model group and vinegar group. Rats in control group got 2ml/kg of sterile water by gavage. Model group rats were additionally supplied with drinking water with 1% (v/v) ethylene glycol (EG) every day. Rats in vinegar group had 1% (v/v) EG in drinking water and were gavaged with 2ml/kg of vinegar (5% acetate) every day. Vinegar reduced renal CaOx crystals and urinary oxalate. Vinegar increased the relative abundances of Ruminococcus gauvreauii, Ruminococcus torques, Ruminococcus-2, Moryella, Enterococcus, Alistipes, and Parabacteroides in the gut microbiota. Blood acetate increased in vinegar group. The renal tight junction occludin protein decreased in the model group and increased in the vinegar group. Studies in vitro verified that acetate could reverse the decline in occludin expression induced by CaOx crystals and inhibit CaOx crystal adhesion to cells. Vinegar reduced renal CaOx stones by regulating gut microbiota and increasing blood acetate to restore renal tight junction and reduce CaOx crystal adhesion.

OXALATE-CALCIUM RATIOS OF COMMON CEREALS CONSUMED IN EASTERN NIGERIA

The importance of Oxalate content of an individual plant in limiting total dietary calcium availability is of significance when the ratio oxalic to calcium (oxa:cal.) is greater than one. Food with oxal: cal ratio greater than two, have no utilizable calcium and contain excess oxalate while foodstuff with oxal:cal. of about one provides little calcium but do not inhibit the utilization of calcium provided by other products. The study analysed three commonly consumed cereals of oxalic acids and calcium by rigorous classical quantitative method of precipitation/titration and atomic absorption spectrophotometry, respectively. The result should oxal:cal. ratios&gt;1 for all the cereals indicating that the cereals have no utilizable calcium, thus contain excess oxalate which not only complex the calcium contained in the food but also that derived from other food sources eaten together with it. This can result in deficiency of such an essential mineral as calcium in the body and even render the body prone to bone diseases and possibility of developing kidney stones due to calcium oxalate formation (calcium oxalate being the most common component of kidney stone).

Pengaruh Konsumsi Air Putih terhadap Gambaran Kalsium Oksalat dalam Urin Mahasiswa Akademi Analis Kesehatan Pekalongan Tahun 2021

Calcium oxalate includes urinary sediment as a combination of calcium and oxalate, calcium can be deposited by oxalate forming calcium oxalate that the body cannot absorb, then into insoluble salt deposits and become kidney stone disease. Water prevents the formation of calcium oxalate crystals. So it is recommended to consume at least 2 liters a day so that the urine released will increase and reduce the concentration of salt and minerals in the body. This study to find out the effect of water consumption on the picture of oxalate crystals in the urine of AAK Pekalongan students before and after consuming water as much as 2 liters per day. Types of analytical observational studies with different T paired test statistical tests, sample numbers of 22 samples and microscopic examination. The results of the study of calcium oxalate in urine before consuming water as much as 2 liters obtained the results of 6 samples (27.28%) negative, 5 samples (22.72%) positive 1.1 sample (4.55%) positive 2 and 10 samples (45.45%) positive 3, while in the sample after consuming water as much as 2 liters obtained 20 samples (90.90%) negative, 1 sample (4.55%) positive 1.1 samples (4.55%) positive 2 and 0 samples (0%) positive 3. Statistical results state that there is an influence before and after water consumption on the picture of calcium oxalate in the urine of AAK Pekalongan students.

Calcium oxalate crystallization in synthetic urinary medium: the impact of resorcinares and calixarenes

The impact of macrocycles on calcium oxalate formation. Calcium oxalate is a major component of kidney stones, an ailment that affects many people globally.

Abiotic Formation of Calcium Oxalate under UV Irradiation and Implications for Biomarker Detection on Mars.

A major objective in the exploration of Mars is to test the hypothesis that the planet has ever hosted life. Biogenic compounds, especially biominerals, are believed to serve as biomarkers in Raman-assisted remote sensing missions. However, the prerequisite for the development of these minerals as biomarkers is the uniqueness of their biogenesis. Herein, tetragonal bipyramidal weddellite, a type of calcium oxalate, is successfully achieved by UV-photolyzing pyruvic acid (PA). The as-prepared products are identified and characterized by micro-Raman spectroscopy and field emission scanning electron microscopy. Persistent mineralization of weddellite is observed with altering key experimental parameters, including pH, Ca2+ and PA concentrations. In particular, the initial concentration of PA can significantly influence the morphology of weddellite crystal. Oxalate acid is commonly of biological origin; thus calcium oxalate is considered to be a biomarker. However, our results reveal that calcium oxalate can be harvested by a UV photolysis pathway. Moreover, prebiotic sources of organics (e.g., PA, glycine, alanine, and aspartic acid) have been proven to be available through abiotic pathways. Therefore, our results may provide a new abiotic pathway of calcium oxalate formation. Considering that calcium oxalate minerals have been taken as biosignatures for the origin and early evolution of life on Earth and astrobiological investigations, its formation and accumulation by the photolysis of abiological organic compounds should be taken into account.

A Study of Phosphate Solubilizing Capacity by Penicillium Aurantiogriseum under Different Carbon and Nitrogen Resources

Phosphate-solubilizing fungi have been successfully applied to the release of phosphorus from insoluble tricalcium phosphate. A phosphate-solubilizing fungi Penicillium aurantiogriseum was isolated and investigated the phosphorus solubilizing capacity under different carbon and nitrogen resources. The highest released phosphorus content reached 1000 mg/L in ammonium and sucrose conditions. Carbon resources did not limit the release of phosphorus by Penicillium aurantiogriseum. However, nitrate and urea significantly reduced the phosphorus release, which had a low phosphorus content (~780 mg/L). Glucose and ammonium were more efficient for fungal growth and organic acid secretion. Oxalic acid secreted by Penicillium aurantiogriseum dominated the release of phosphorus. The formed calcium oxalate promoted the dissolution of tricalcium phosphate. This study indicated that the effective utilization of Penicillium aurantiogriseum to dissolve tricalcium phosphate need to support more ammonium nitrogen.

Association between hyperlipidemia and calcium oxalate lower urinary tract uroliths in dogs.

BackgroundMetabolic syndrome is associated with formation of calcium oxalate (CaOx) uroliths in humans.ObjectivesTo investigate the association between obesity and hyperlipidemia with CaOx lower urinary tract uroliths in client‐owned dogs.AnimalsDogs with (n = 55, U [uroliths]‐dogs) and without (n = 39, UF [uroliths‐free]‐dogs) CaOx lower urinary tract uroliths.MethodsCase‐control study. U‐dogs were retrospectively enrolled and compared to UF‐dogs. Body condition score (BCS; 1‐9 scoring scale), serum triglyceride (TG) and total cholesterol (CH) concentrations and glycemia (after >12‐hour food withholding) were recorded in both groups.ResultsOn univariate logistic regression, when excluding Miniature Schnauzers, odds of having uroliths increased by a factor of 3.32 (95% CI 1.38‐11.12) for each mmol/L of TG (P = .027), of 39 (95% CI 9.27‐293.22) for each mmol/L of glycemia (P < .0001), and of 2.43 (95% CI 1.45‐4.45) per unit of BCS (P = .002). In multivariable models, the effect of TG was retained when all breeds were included for analysis and odds of having uroliths increased by a factor of 4.34 per mmol/L of TG (95% CI 1.45‐19.99; P = .02).Conclusions and Clinical ImportanceSerum lipid screening in dogs diagnosed with CaOx uroliths might be recommended to improve their medical staging and management.