Carbonate Apatite Research Articles

Carbonate apatite: effect of serum and impact on the cellular proteome

Carbonate apatite (CA) is a synthetic derivative of hydroxyapatite, which we have been exploring as a drug delivery nanocarrier in the context of cancer in vitro and in vivo. This nanocarrier showed great potential delivering anti-cancer drugs, plasmids containing tumour suppressor genes and siRNAs against oncogenes in pre-clinical models. We compared here two formulations of CA—the low-Ca2+ CA (made with 4 mM Ca2+) used for in vitro studies in cell lines and the high-Ca2+ CA (made with 40 mM Ca2+) used in mouse models—in terms of protein corona formed with different concentrations of serum in vivo and in vitro. The 10-fold more Ca2+ in high-Ca2+ CA helped produce enough particles in an injectable volume for in vivo delivery of therapeutics. Both formulations made particles of similar size, but their composition differed slightly in terms of Na and Mg content. In serum-containing media, the size of the particles was dependent on the serum concentration. The protein corona around both formulations was almost similar and included albumin, fetuin, haemoglobin, and immunoglobulins. CA was not cytotoxic, and instead an increased expression of ribosomal machinery and glycolytic and cytoskeletal proteins was observed, which promoted translation, growth, and proliferation in cancer cells.

Fluorine soil stabilization using hydroxyapatite synthesized from minerals wastes

The objective of this study was to present a new approach to mineral waste valorization, based on the synthesis of hydroxyapatite (HAP) as an efficient and cost-effective adsorbent for the stabilization of fluorides (F-) in soil. Hydroxyapatites were synthesized from the reaction of potassium dihydrogen phosphate (KH2PO4) and waste paper fly ash (WPFA), fine limestone clay (FLC) and limestone filler (LF) rich in calcite. X-ray diffraction characterization results showed that for HAPFLC and HAPFL the main resulting phases were brushite (CaHPO5·2H2O) and for HAPWPFA was hydroxyapatite (Ca5(PO4)3OH). The FTIR spectra showed similar patterns to natural HAP containing orthophosphate groups (PO43-), hydroxylated groups (OH–) and both types A/B of carbonate apatite. SEM-EDS analysis of the individual HAP revealed a morphology consistent with phosphocalcic hydroxyapatite crystals. EDS analysis revealed a Ca/P atomic ratio equal to 1.92, 1.85 and 1.7 for HAPFLC, HAPLF and HAPWPFA respectively, which is similar to the stoichiometry of hydroxyapatites (Ca/P = 1.67). The use of HAP as an amendment to stabilize fluorides (F-) in the soil was demonstrated to be effective, the addition of 1% of the different HAP allowed the decrease of the concentration of F in the raw soil (73.8 mg/kg) to concentrations below the IWSI threshold (10 mg/kg), to 4.68 mg/kg, 5.63 mg/kg, and 0.8 mg/kg for HAPFLC, HAPFL and HAPWPFA respectively. Fluoride (F) sequential extraction results showed that it was extracted from the residual fraction (Fraction 4) after soil treatment, and was generally trapped on the hydroxyapatites (Ca5(PO4)3(OH)) by anion exchange with the hydroxides (OH–) to form the stable and insoluble fluorapatite ((Ca5(PO4)3F).

Ant-nest type porous scaffold with micro-struts consisting of carbonate apatite for promoting bone formation and scaffold resorption.

Scaffolds having appropriate mechanical strength and providing a proper microenvironment for osteogenesis are expected to be effective alternatives to autografts for bone regeneration. In this study, ant-nest type porous (ANP) scaffolds consisting of CO3 Ap were fabricated using calcium carbonate powder or slurry and two types of polyurethane foam through a dissolution-precipitation reaction. ANP-type, three-dimensional, interconnected porous CO3 Ap scaffolds were fabricated by burning out the struts of polyurethane foams embedded in CaCO3 , followed by compositional transformation from CaCO3 to CO3 Ap. The types of polyurethane foam and impregnation methods of CaCO3 into polyurethane form affected the geometry of the resulting ANP structures. Mechanical and in vivo biological performances of these scaffolds relied on the geometry of the ANP structures. The ANP structures displayed had a clear structural advantage in bone regeneration, owing to the promotion of cell and tissue migration throughout the scaffolds. In particular, ANP-structured scaffolds, which had highest porosity, interconnectivity, and smallest strut thickness, had a mechanical strength comparable to cancellous bone, formed more new bone, were highly resorbed, resulting in cancellous bone-like bone tissue regeneration at 12 weeks of healing. The results suggest that bone regeneration after the migration of cell and tissue into the entire scaffolds is affected by strut thickness preferentially over porosity and interconnectivity. ANP-structured CO3 Ap scaffolds are attractive for bone regeneration.

Clinical outcomes of periodontal regenerative therapy with carbonate apatite granules for treatments of intrabony defects, Class II and Class III furcation involvements: A 9-month prospective pilot clinical study

IntroductionCarbonated apatite (CO3Ap) has unique properties as an alloplastic bone substitute and has been reported the safety and efficacy for bone regeneration. However, no previous studies reported the clinical application of CO3Ap for periodontal regeneration therapy. The aim of this study was to evaluate the safety and efficacy of periodontal regeneration with CO3Ap in treating intrabony defects, Class II and Class III furcation involvement (FI). MethodsA single-arm and single-center prospective pilot clinical study was performed to verify the safety and efficacy of CO3Ap in patients with periodontitis. A total of four patients with seven teeth, including three deep intrabony defects, two Class II FI, and two Class III FI, were treated with CO3Ap. The clinical parameters, including probing pocket depth (PPD), clinical attachment level (CAL), bleeding on probing (BOP), tooth mobility (Mo), Plaque index (PI), and Gingival index (GI) were evaluated at baseline, 6 months, and 9 months after the surgery. Radiographic analysis was conducted on images of dental X-ray and cone beam computed tomography (CBCT) at baseline and 9 months post-surgery. ResultsThe postoperative healing in all cases was uneventful, with no abnormal bleeding, pain, or swelling. The mean PPD reduction and CAL gain were 5.0 ± 1.0 mm, 4.5 ± 0.7 mm, 1.5 ± 0.7 mm, and 4.7 ± 1.2 mm, 4.5 ± 0.7 mm, 0.0 mm for intrabony defect, Class II and Class III FI, respectively. According to radiographic analysis, linear bone height in intrabony defects and vertical subclassification of FI in Class II FI were improved. ConclusionsThe clinical application of CO3Ap for the treatment of intrabony defects and Class II FI could be effective for periodontal regeneration, although its efficacy in treating Class III FI might be limited. Despite the limitations of this study, the findings in this study suggested that CO3Ap has the potential to be a promising bone graft substitute for periodontal regeneration.

Fabrication of silica-substituted carbonate apatite blocks through phase transformation process from silica-substituted octacalcium phosphate blocks

Fabrication of silica-substituted carbonate apatite blocks through phase transformation process from silica-substituted octacalcium phosphate blocks

Superiority of Triply Periodic Minimal Surface Gyroid Structure to Strut-Based Grid Structure in Both Strength and Bone Regeneration.

The aging population has rapidly driven the demand for bone regeneration. The pore structure of a scaffold is a critical factor that affects its mechanical strength and bone regeneration. Triply periodic minimal surface gyroid structures similar to the trabecular bone structure are considered superior to strut-based lattice structures (e.g., grids) in terms of bone regeneration. However, at this stage, this is only a hypothesis and is not supported by evidence. In this study, we experimentally validated this hypothesis by comparing gyroid and grid scaffolds composed of carbonate apatite. The gyroid scaffolds possessed compressive strength approximately 1.6-fold higher than that of the grid scaffolds because the gyroid structure prevented stress concentration, whereas the grid structure could not. The porosity of gyroid scaffolds was higher than that of the grid scaffolds; however, porosity and compressive strength generally have a trade-off relationship. Moreover, the gyroid scaffolds formed more than twice the amount of bone as grid scaffolds in a critical-sized bone defect in rabbit femur condyles. This favorable bone regeneration using gyroid scaffolds was attributed to the high permeability (i.e., larger volume of macropores or porosity) and curvature profile of the gyroid structure. Thus, this study validated the conventional hypothesis using in vivo experiments and revealed factors that led to this hypothetical outcome. The findings of this study are expected to contribute to the development of scaffolds that can achieve early bone regeneration without sacrificing the mechanical strength.

Group Replacement-Rearrangement-Triggered Linear-Assembly Nonaqueous Precipitation Synthesis of Hydroxyapatite Fibers.

A novel method for hydroxyapatite fiber preparation with highly large-scale production prospects is of paramount importance but remains particularly difficult. Here, group replacement-rearrangement-triggered linear-assembly nonaqueous precipitation synthesis has been proposed for hydroxyapatite fibers under mild conditions. Pure hydroxyapatite fibers can be fabricated taking disodium hydrogen phosphate, calcium acetate, and glycerol as the phosphorus source, calcium source, and solvent, respectively. Single hexagonal crystal structures of hydroxyapatite fibers growing along the c-axis and preferential growth of the (002) crystal plane similar to the layered stacking structure of an adult bone have been confirmed by XRD refinement tests and calculation, TEM electron diffraction calibration, and FE-SEM. Highly active carbonate apatite is further demonstrated by EDS, FT-IR, Raman spectroscopy, and XPS. Unsaturated P-O and O-Ca bonds at both ends of the hexagonal-sheet assembly unit in a high-polarity nonaqueous glycerol environment without strongly coordinated OH- confirm the solution spontaneous linear assembly to form the single hydroxyapatite fibers.

Identifying surface phonons in the vibrational spectra of carbonated apatite using density functional theory

Vibrational spectroscopy is widely used to examine the mineralogy of bone apatite. Yet, these spectra may be significantly influenced by the nanometre size of the crystallites through either phonon confinement or surface phonon contributions. This could lead to misinterpretations of the implications of non-apatitic environments that have been described previously as additional bands in the vibrational spectra. Here we use density functional theory to simulate bulk and slabs of hydroxyapatite as well as A-type, B-type, and AB-type carbonated apatite to test for eventual contributions of surface phonons. The analysis showed that surface phonons can have a significant intensity in the vibrational spectra. They are expected at both higher and lower wavenumbers than their bulk counterparts, unlike phonon confinement which has been linked with only lower wavenumber shifts. The band shift of surface phonons was up to 40 cm−1, which is determinable by both Raman and Infrared spectroscopy. All internal modes of evaluated molecular groups (OH, CO3, PO4) were affected by the surface presence. Therefore, it is expected that surface phonons are likely to be present in the vibrational spectra of bone minerals and contribute to spectral effects such as line broadening, presenting a crucial factor in their interpretation and application.

Preparation of novel porous hydroxyapatite sheets with high Pb2+ adsorption properties by self-assembly non-aqueous precipitation method

Herein, novel porous hydroxyapatite sheets with high pore homogeneity are prepared via a self-assembly nonaqueous precipitation method. The optimized calcium source, phosphorus source and solvent are calcium acetate, disodium hydrogen phosphate and glycerin, respectively. Hexagonal plate-like hydroxyapatite polycrystals form in the replacement-rearrangement groups of raw materials and grow along the (002) crystal plane of the hydroxyapatite phase. Large hydroxyapatite sheets have homogeneous pore sizes of approximately 110 nm and thicknesses of approximately 20 nm. The hydroxyapatite sheets prepared via the nonaqueous precipitation method are highly active carbonate apatite. In a nonaqueous environment, assembly units of hexagonal plate-like hydroxyapatite polycrystals are triggered by the replacement and rearrangement of groups in the raw materials, and they self-assemble to form large hydroxyapatite sheets in the form of edge sharing. The degree of curvature in the process of plate-like hydroxyapatite self-assembly triggers the formation of porous hydroxyapatite sheets. This material has excellent adsorption performance for Pb2+ ions. The material developed in this work has wide application prospects in the fields of adsorption treatment of wastewater containing toxic ions (such as Pb2+), and it is expected to become a novel type of lead ion adsorbent.

Temperature effects on elastic constants and related properties of apatites

The application of apatites, a class of naturally occurring calcium phosphate minerals with the most common forms being hydroxyapatite (HAP), fluorapatite (FAP) and chlorapatite (ClAP), range from primary production of phosphorus, to bone and dental implants, to potential usage in carbon sequestration and nuclear waste immobilization including those that involve exposure to high temperatures. Due to their hexagonal structure, apatites have five independent elastic constants: nevertheless, experimental studies commonly report isotropic properties, and limited computational results available in the literature exhibit a large scatter. Moreover, investigation of temperature dependence of apatite elastic properties which would be essential for designing future applications is yet to be addressed in the current state of the art. In this work, we evaluate the single crystal elastic constants of the three apatite structures using stress–strain relationships: first from density functional theory (DFT) using ultrasoft pseudopotential with PBEsol exchange–correlation functional under generalized gradient approximation (GGA) on a single unit cell , and then with molecular dynamics (MD) with a 5×5×5 unit cell using a core–shell based potential model at temperatures varying from 10K to 1500K. In this temperature range, apatites exhibit the highest stiffness along the ‘c’ axis, and their elastic constants noticeably decrease with increasing temperature. At very high temperatures, C33 becomes greater than C11 for both FAP and ClAP. It is noteworthy that our DFT study exhibits better conformity with experimental findings when compared to other DFT studies reported in literature. Additionally, MD studies have demonstrated favorable consistency in predicting elastic constants, potentially as a result of fitting potential parameters to experimental data. We also calculate various effective isotropic elastic properties from our single crystal MD results and study their temperature dependence as a substitute for first principles modeling of large polycrystalline systems. All the apatites have very comparable bulk, shear, and elastic moduli, but FAP has slightly higher values, and interestingly, HAP’s Poisson’s ratio shows no variation with temperature. This study sets the baseline with which any future studies on high-temperature applications of apatites (such as carbonate or radionuclide rich apatites) can be compared.

Phase transformation and mechanical properties of new bioactive glass-ceramics derived from CaO–P2O5–Na2O–B2O3–SiO2 glass system

This work investigates the role of sintering temperature on bioactive glass-ceramics derived from the new composition CaO–P2O5–Na2O–B2O3–SiO2 glass system. The sintering behaviour of the samples’ physical, structural, and mechanical properties is highlighted in this study. The experimental results indicated that the sintering process improved the crystallization and hardness of the final product. Results from XRD and FTIR showed the existence of carbonate apatite, pseudo-wollastonite, and wollastonite phases. From the results, the bioglass-ceramics sintered at 700 °C obtained the highest densification and optimum mechanical results. It had the value of 5.34 ± 0.21 GPa regarding microhardness and 2.99 ± 0.24 MPa m1/2 concerning fracture toughness, which falls in the range of the human enamel. Also, the sintered samples maintained their bioactivity and biodegradability after being tested in the PBS medium. The bioactivity does not affect but slows down the apatite formation rate. Overall results promoted the novel bioglass-ceramics as a candidate material for dental application.

Carbonate apatite as a bone substitute material. A review

Carbonate apatite as a bone substitute material. A review

Reconstruction of Load-Bearing Segmental Bone Defects Using Carbonate Apatite Honeycomb Blocks

In a globally aging society, synthetic bone blocks are in increasing demand. An ideal synthetic bone block fuses early with bone and is replaced with new bone at a suitable speed while withstanding the weight load. Herein, we report carbonate apatite honeycomb (HC) blocks with superior mechanical strength, osteoconductivity, and bioresorbability compared to a clinically used synthetic porous block (control block). Three types of HC blocks were fabricated via the debinding of HC green bodies at 600, 650, and 700 °C and subsequent phosphatization, designated as HC-600, HC-650, and HC-700, respectively. The macropores in these HC blocks uniaxially penetrated the blocks, whereas those in the control block were not interconnected. Consequently, the HC blocks exhibited higher open macroporosities (18%–20%) than the control block (2.3%). In contrast, the microporosity of the control block (46.4%) was higher than those of the HC blocks (19%–30%). The compressive strengths of the HC-600, HC-650, HC-700, and control blocks were 24.7, 43.7, 103.8, and 38.9 MPa, respectively. The HC and control blocks were implanted into load-bearing segmental bone defects of rabbit ulnae. Uniaxial HC macropores enabled faster bone ingrowth than the poorly interconnected macropores in the control block. Microporosity in the HC blocks affected bone formation and osteoclastic resorption over a period of 24 weeks. The resorption of HC-650 corresponded to new bone formation; therefore, new bone with strength equal to that of the original bone bridged the separated bones. Thus, the HC blocks achieved the reconstruction of segmental bone defects while withstanding the weight load. The findings of this study contribute to the design and development of synthetic bone blocks for reconstructing segmental defects.

Estonian Phosphate Rock Dissolution in Hydrochloric Acid: Optimization of Acid Dosage and Concentration

The increasing need for phosphorus and rare earth elements (REEs) has initiated the studies of new mineral deposits and new complex processing technologies. Estonian phosphate rock (EPR) resources, which are not in use, are estimated to be more than 3 billion metric tons or 800 million tons of P2O5. The experiments of dissolution of three different EPR samples in hydrochloric acid were carried out with the aim of studying the impact of the chemical and mineralogical composition of EPR on the leaching process. The leaching of P, Ca, Mg, and consumption of H+ ions depend on HCl concentration and dosage. The solubility of fluorine and REEs are also influenced by CaF2 and REEs-phosphates precipitation. Fe solubility depends on the mineralogical composition of EPR but also on particle size, acid dosage, pH, and phosphorus content in the solution. The dissolution of pyrite is much lower than the solubility of carbonate apatite. Dolomite dissolution depends on the acid dosage and the fractional composition of EPR. Dolomite dissolution also rests lower than that of apatite. For all the samples studied, the best regression models that describe P, Mg, and Ca solubility and the optimum concentration of HCl for phosphorus dissolution were found using mathematical modeling.

Super Carbonate Apatite-miR-497a-5p Complex Is a Promising Therapeutic Option against Inflammatory Bowel Disease.

The incidence of inflammatory bowel disease (IBD) is increasing worldwide. It is reported that TGF-β/Smad signal pathway is inactivated in patients with Crohn's disease by overexpression of Smad 7. With expectation of multiple molecular targeting by microRNAs (miRNAs), we currently attempted to identify certain miRNAs that activate TGF-β/Smad signal pathway and aimed to prove in vivo therapeutic efficacy in mouse model. Through Smad binding element (SBE) reporter assays, we focused on miR-497a-5p. This miRNA is common between mouse and human species and enhanced the activity of TGF-β/Smad signal pathway, decreased Smad 7 and/or increased phosphorylated Smad 3 expression in non-tumor cell line HEK293, colorectal cancer cell line HCT116 and mouse macrophage J774a.1 cells. MiR-497a-5p also suppressed the production of inflammatory cytokines TNF-α, IL-12p40, a subunit of IL-23, and IL-6 when J774a.1 cells were stimulated by lipopolysaccharides (LPS). In a long-term therapeutic model for mouse dextran sodium sulfate (DSS)-induced colitis, systemic delivery of miR-497a-5p load on super carbonate apatite (sCA) nanoparticle as a vehicle restored epithelial structure of the colonic mucosa and suppressed bowel inflammation compared with negative control miRNA treatment. Our data suggest that sCA-miR-497a-5p may potentially have a therapeutic ability against IBD although further investigation is essential.

Analysis of the Physical, Chemical and Mineralogical Properties of Gallstones in the Antalya Province of Turkey

The aim of the study is to determine chemical and physical properties of gallstones of Antalya province. In line with this, the chemical and mineralogical characteristics of 1243 gallstone samples from 69 patients were analyzed, using scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) analysis. 
 Cholesterol, carbonate apatite, calcium carbonate, calcium phosphate carbonate, calcium bilirubinate, and protein contents were observed. Cholesterol was detected in 95% of 69 samples patients, 44 of which were obtained from female patients. X-Ray Diffractometer (XRD) analysis showed newberyite, struvite, and aragonite minerals were found in the gallstones. Newberyite was present in 59% of the samples.
 Newberyite precipitates in cases where the pH value of the patient’s bile decreases and where the amount of magnesium in the bile is high. Failure in the degradation magnesium during metabolism may lead to the formation of newberyite in gallstones. Struvite is associated with the presence of ammonium phosphate in bile. Ammonium phosphate is present in plant fertilizers and can easily be dissolved in water. These minerals (newberyite and struvite) are present in the human body and, more importantly, are intricately involved in the body’s production and destruction mechanisms. Therefore, determining the source of these minerals is crucial for understanding the mechanisms of gallstone formation.

New formulation calcium-based 45S5 bioactive glass: In vitro assessment in PBS solution for potential dental applications

In this work, the designed bioactive glass utilized waste is expected to improve mechanical properties while maintaining the bioactivity performance during the in-vitro assessment. Herein, the novel bioactive glasses were prepared using the melt-quenching approach. Phosphate buffer saline was used as an immersion medium during the in-vitro bioactivity and biodegradability evaluation to ascertain the glass's bioactivity characteristics. The XRD results indicated the carbonate apatite phase for sample 0F and the fluorapatite and calcite phase for sample 3F, supported by the FTIR spectra. Further, the pH increased from (7.437 ± 0.004) to (9.699 ± 0.058) for 0F and (9.635 ± 0.014) for 3F, indicating the samples' bioactivity in response to the immersion medium. In addition, 3F exhibited a higher hardness (3.29 ± 0.07 GPa) and toughness (2.4 ± 0.08 MPa m1/2), supported by the weight gained in the biodegradability analysis. This work offers a promising technique to fabricate the bioactive glass incorporating waste, adding fluoride content into the glass for potential dental application.

Abstract 2698: Improved calcium phosphate delivery system cNaD to aim clinical application

Abstract Super carbonate apatite (sCA) nanoparticle is a superb calcium phosphate delivery system for miRNA and siRNA to tumors (PlosOne 2015). We reported that sCA delivered efficiently siRNA for survivin and PTBP as well as miR-340 (Mol Cancer Ther 2015, 2015) to colon tumors implanted into nude mice. MiR-4689 and miR-29b-1-5p suppressed KRAS mutated colon cancer cells (Mol Ther NA2015, 2018) and miR-302 and miR-369 realized in vivo cancer reprograming (PlosOne 2015). In every case the RNA function was fully realized. Moreover, effect of influenza vaccination was augmented by sCA plus CpG nucleic acid (NA) (Frontiers in Immunol 2018). sCA coupled with miR-29a or miR-29b prevented the DSS (dextran sodium sulfate)-induced inflammatory bowel disease (Mol Ther NA2018). We also applied the sCA-ICG complex to minimally invasive treatment of photodynamic therapy (Mol Cancer Ther 2018). Following these outstanding findings, we tried and succeeded to establish a clinically available novel calcium phosphate delivery system, named cNaD, which controls the nano-particle size and avoids accumulation in normal organs including liver and spleen. It is characterized by its ability to efficiently deliver siRNA and microRNA to cancers and provided prominent therapeutic effect in various mouse models. Safety test has been accomplished in rats and monkeys based on GLP standards. Also, the scale-up manufacturing system >1000 folds has been attained. Our cNaD system will accelerate the development of NA medicine in the world. Citation Format: Hirofumi Yamamoto. Improved calcium phosphate delivery system cNaD to aim clinical application [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2698.

MP16-11 CARBONATE APATITE NEPHROLITHIASIS

You have accessJournal of UrologyCME1 Apr 2023MP16-11 CARBONATE APATITE NEPHROLITHIASIS Nick Dean, Jenny Guo, and Amy Krambeck Nick DeanNick Dean More articles by this author , Jenny GuoJenny Guo More articles by this author , and Amy KrambeckAmy Krambeck More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003236.11AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Carbonate apatite (CA) stones are commonly referred to as infection stones given their formation in the presence of bacterial infection and their association with positive urine and stone cultures. Anecdotally at our institution, we observed patients who were found to have CA stones on post-operative stone analysis without positive stone cultures, positive pre-operative urine cultures, or a history of urinary tract infections (UTIs). The aim of our study is to characterize patients with CA stones, with and without evidence of infection, and examine their clinical outcomes. METHODS: We retrospectively identified patients in our prospectively maintained stone database who had undergone surgical treatment for calculi containing CA on final stone analysis. SPSS was used to perform descriptive statistics and two-tailed T tests (p<0.05). RESULTS: We identified 53 patients with CA stones from our database. Most patients were female (n=35, 66.0%) and had undergone percutaneous nephrolithomy (PCNL) (n=44, 83.0%). Mean follow-up was 13.8 months. Almost all patients with CA stones had a documented vitamin D deficiency (n=47, 88.7%) and were prescribed vitamin D supplementation (n=46, 86.8%). Patients had a mean pre-operative stone burden of 2.8 cm (range 0.5-20 cm) and over half of the patients had a positive pre-operative urine culture, post-operative stone culture, or history of UTIs (n=28, 52.8%). Patients with evidence of infection (infection stones) were more likely to have a GU anatomical abnormality (39% vs 4%, p<0.002), greater proportion of CA on stone analysis (51% vs 32%, p=0.037), hypocitraturia on 24-hour urine collection (85% vs 50%, p=0.06), and lower rates of freedom from next stone procedure (82% vs 96%, p=0.12). Patients with infection CA stones did not have longer lengths of stay, worse stone free rates, greater rates of ER presentations, or re-admission rates (all p>0.05) compared to patients without evidence of infection. CONCLUSIONS: Patients with CA stones have a high prevalence of vitamin D deficiency and prescribed vitamin D replacement. Patients with CA stones and evidence of infection tend to have higher proportions of CA on stone analysis, greater rates of hypocitraturia on 24-hour urine collections, and may have lower rates of freedom from subsequent stone treatment compared to patients without evidence of infection. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e206 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Nick Dean More articles by this author Jenny Guo More articles by this author Amy Krambeck More articles by this author Expand All Advertisement PDF downloadLoading ...

LBA01-16 COMPARATIVE ANALYSES AND ABLATION EFFICACY OF THULIUM FIBER LASER BY STONE COMPOSITION

You have accessJournal of UrologyCME1 Apr 2023LBA01-16 COMPARATIVE ANALYSES AND ABLATION EFFICACY OF THULIUM FIBER LASER BY STONE COMPOSITION Jeffrey Johnson, Miyad Movassaghi, David Han, Srinath-Reddi Pingle, Justin Lee, Prakash Gorroochurn, James Williams, Michael Schulster, and Ojas Shah Jeffrey JohnsonJeffrey Johnson More articles by this author , Miyad MovassaghiMiyad Movassaghi More articles by this author , David HanDavid Han More articles by this author , Srinath-Reddi PingleSrinath-Reddi Pingle More articles by this author , Justin LeeJustin Lee More articles by this author , Prakash GorroochurnPrakash Gorroochurn More articles by this author , James WilliamsJames Williams More articles by this author , Michael SchulsterMichael Schulster More articles by this author , and Ojas ShahOjas Shah More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003360.16AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: There is limited data on the ablation settings and photothermal effects of thulium fiber laser (TFL) lithotripsy across various stone compositions. We aim to identify settings by stone type that optimize efficiency and avoid undesirable effects (i.e. charring) during TFL lithotripsy. METHODS: Specimens of calcium oxalate monohydrate, calcium oxalate dihydrate, uric acid, struvite, cystine, carbonate apatite and brushite stones were ablated to ≤1mm residual fragments using 13 settings with the Coloplast© TFL Drive. Pre-ablation mass, post-ablation mass, ablation time and total energy were recorded. Samples were analyzed using FTIR spectroscopy and electron microscopy. RESULTS: Pulse duration impacted ablation effectiveness greatly with 75% of inadequate ablations occurring in medium or long pulse settings. Calcium oxalate dihydrate, cystine, and struvite ablated most efficiently with 0.2J×100Hz, short pulse. Calcium oxalate monohydrate ablated most efficiently with 0.4J×40Hz, short pulse. The average percent of mass lost during ablation was 57%; cystine averaged the highest at 71%. Charring was seen in 40% of stones, mostly in uric acid, cystine, and brushite stones. Electron microscopy of char demonstrated a porous melting effect. FTIR spectroscopy of brushite char demonstrated a chemical composition change to amorphous calcium phosphate. CONCLUSIONS: Our trial is the first in vitro trial on stone ablation efficacy by stone composition. Across all settings and stone types 0.05J×1000Hz was the most effective ablation setting, however this is above our clinically recommended power of <=20 W. When operating in the kidney and using clinically acceptable TFL settings to minimize the risk of thermal injury, we recommend starting with short pulse 0.2J×100Hz and 0.4J×40Hz to cover most stone types, and adjusting the settings based on visual ablation effects intraoperatively and the clinical scenario (e.g. limited irrigation flow, narrow infundibulum). Further investigation is needed to continue to optimize TFL stone treatment settings. Source of Funding: Coloplast © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e1183 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Jeffrey Johnson More articles by this author Miyad Movassaghi More articles by this author David Han More articles by this author Srinath-Reddi Pingle More articles by this author Justin Lee More articles by this author Prakash Gorroochurn More articles by this author James Williams More articles by this author Michael Schulster More articles by this author Ojas Shah More articles by this author Expand All Advertisement PDF downloadLoading ...