Calcium Mass Research Articles

Coronary artery calcium quantification technique using dual energy material decomposition: a simulation study

Coronary artery calcification is a significant predictor of cardiovascular disease, with current detection methods like Agatston scoring having limitations in sensitivity. This study aimed to evaluate the effectiveness of a novel CAC quantification method using dual-energy material decomposition, particularly its ability to detect low-density calcium and microcalcifications. A simulation study was conducted comparing the dual-energy material decomposition technique against the established Agatston scoring method and the newer volume fraction calcium mass technique. Detection accuracy and calcium mass measurement were the primary evaluation metrics. The dual-energy material decomposition technique demonstrated fewer false negatives than both Agatston scoring and volume fraction calcium mass, indicating higher sensitivity. In low-density phantom measurements, material decomposition resulted in only 7.41% false-negative (CAC = 0) measurements compared to 83.95% for Agatston scoring. For high-density phantoms, false negatives were removed (0.0%) compared to 20.99% in Agatston scoring. The dual-energy material decomposition technique presents a more sensitive and reliable method for CAC quantification.

Effects of dietary glucosamine sulfate sodium on early laying performance and eggshell quality of laying hens

This study was conducted to determine the influence of dietary glucosamine sulfate sodium (GSS) on laying performance, blood profiles, eggshell and inner quality of eggs and relative expression of the genes related to eggshell in laying hens at early stage. A total of 640 twenty-weeks-old Lohmann laying hens were randomly allotted to 4 treatments with 10 replicates of 16 hens each. The experiment lasted for 8 wk, and dietary treatments were: 1) CON, basal diet; 2) G1, CON + 0.2% GSS; 3) G2, CON + 0.4% GSS; 4) G3, CON + 0.6% GSS. The inclusion of GSS increased average daily feed intake, laying rate, and egg mass (P < 0.05) linearly during wk 21 to 25, 25 to 29, and 21 to 29, egg weight during wk 21 to 25 and 25 to 29, and improved (P < 0.05) feed conversion ratio linearly during wk 21 to 25. The supplementation of GSS increased (P < 0.05) albumen height quadratically, Haugh unit, calcium content, calcium mass, phosphorus content and phosphorus mass linearly at the end of 25th and 29th wk. At the end of 29th wk, the eggshell strength, eggshell weight, eggshell ratio, and eggshell thickness were increased (P < 0.05) linearly in GSS treatments compared with CON. The addition of GSS increased (P < 0.05) serum calcium, estrogen 2, and calcitonin, while decreased (P < 0.05) serum tartrate resistant acid phosphatase (TRAP), parathormone, IL-6 and prostaglandin E2 (PGE2) at the end of 29th wk. The inclusion of GSS increased (P < 0.05) the relative expression of ovocalyxin-32 and ovocalyxin-36 linearly at the end of 29th wk, and ovalbumin, osteopontin, calbindin 1, and ovocleidin-116 linearly at the end of 25th and 29th wk. Quadratic effects were observed (P < 0.05) in the laying rate during wk 21 to 25, serum TRAP and PGE2, the relative expression of ovocleidin-116 at the end of 29th wk. In summary, the inclusion of GSS up-regulated relative expression of osteopontin, ovocleidin-116, ovocalyxin-32 and ovocalyxin-36 in uterus, promoted the serum PGE2 and calcitonin, thus increased the calcium content of eggshell and finally enhanced eggshell quality.

Calcium mass balance in adults during single hemodialysis and hemodiafiltration treatments using lower calcium dialysate concentrations.

Debate continues as to the optimum hemodialysis (HD) dialysate calcium concentration. Although current guidelines advocate 1.25-1.5 mmol/L, some investigators have suggested these may cause calcium gains. As such we investigated whether using dialysate calcium of 1.25 mmol/L risked calcium gains, and whether there were differences between hemodiafiltration and high flux HD. We continuously collect an aliquot of effluent dialysate during dialysis sessions, and calculated dialysis calcium mass balance by the difference between the amount of calcium delivered as fresh dialysate and that lost in effluent dialysate. We studied 106 stable outpatients, 64% male, mean age 64.4 ± 16.2 years, median dialysis vintage 32 (22-60) months. Most sessions (69%) used a 1.0 mmol/L calcium dialysate, with a median sessional loss of 13.7 (11.5-17.1) mmol, whereas using 1.25 mmol/L the median loss was 7.4 (4.9-10.1) mmol, but with 6.9% had a positive balance (p = 0.031 vs dialysate calcium 1.0 mmol/L). Most patients (85.8%) were treated by hemodiafiltration, but there was no difference in sessional losses (11.7 (8.4-15.8) vs 13.5 (8.1-16.8)) with high flux HD. Dialysis sessional calcium balance was associated with the use of lower dialysate calcium concentration (β -19.5, 95% confidence limits (95%CL) -27.7 to -11.3, p < 0.001), and sessional duration (β 0.07 (95% CL) 0.03-012, p = 0.002). Ideally, the choice of dialysate calcium should be individualized, but clinicians should be aware, that even when using a dialysate calcium of 1.25 mmol/L, some patients are at risk of a calcium gain during hemodiafiltration and high-flux hemodialysis.

Influence of biochar in the calcite precipitation of sandy soil using sporosarcina ureae

The microbially induced calcium carbonate precipitation (MICP) technology is an emerging novel and sustainable technique for soil stabilization and remediation. MICP, a microorganism-mediated biomineralization process, has attracted interest for its potential to enhance soil characteristics. The inclusion of biochar, a carbon-rich substance formed by biomass pyrolysis, adds another degree of intricacy to this process. The study highlights the impact of the combination of biochar and MICP together, using a bacterium, Sporosarcina ureae, on soil improvement. This blend of MICP and biochar improved the soil in terms of its geotechnical properties and also enabled the sequestering of carbon safely. It was observed that addition of 4% biochar significantly increased the soil's shear strength parameters (c and φ) as well as its stiffness after 21 treatment cycles. This improvement was because the calcium carbonate precipitate, which acts as a crucial binding agent, increased significantly due to microbial action in the soil-biochar mixture compared to the pure soil sample. The excess carbonate precipitation on account of biochar addition was verified through SEM-EDAX analysis where the images showed noteworthy carbonate precipitation on the surface of particles and increment in the calcium mass at the same treatment cycles when compared with untreated sand. The collaboration between MICP and biochar effectively increased the carbon sequestration within the sand sample. It was observed that at 21 cycles of treatment, the carbon storage within the sand sample increased by almost 3 times at 4% biochar compared to sand without any biochar. The statistical analysis further affirmed that strength depends on both biochar and the number of treatment cycles, whereas carbon sequestration potential is primarily influenced by the biochar content alone. This strategy, as a sustainable and environmentally friendly approach, has the potential to reform soil improvement practices and contribute to both soil strength enhancement and climate change mitigation, supporting the maintenance of ecological balance.

Effect on thermal, mechanical, and biodegradable properties of plasma‐treated fish scale powder/linear low‐density polyethylene polymer composite films

AbstractIn the present work, we report the effect of low‐temperature plasma treatment on thermal, mechanical, and biodegradable properties of polymer composite blown films prepared from carp fish scale powder (CFSP) and linear low‐density polyethylene (LLDPE). The CFSP was melt compounded with LLDPE using a filament extruder to prepare 1, 2, and 3 wt.% of CFSP in LLDPE polymer composite filaments. These filaments were further pelletized and extruded into blown films. The blown films extruded with 1, 2, and 3 wt.% of CFSP in LLDPE were tested for thermal and mechanical properties. It was observed that the tensile strength decreased with the increased loading content of CFSP, and 1% CFSP/LLDPE exhibited the highest tensile strength. To study the effect of low‐temperature plasma treatment, 1% CFSP/LLDP polymer composite with high tensile strength was plasma treated with O2 and SF6 gas before blow film extrusion. The 1% CFSP/LLDPE/SF6‐extruded blown films showed increased thermal decomposition, crystallinity, tensile strength, and modulus. This may be due to the effect of crosslinking by the plasma treatment. The maximum thermal decomposition rate, crystallinity %, tensile strength, and modulus obtained for 1% CFSP/LLDPE/SF6 film were 500.02°C, 35.79, 6.32 MPa, and 0.023 GPa, respectively. Furthermore, the biodegradability study on CFSP/LLDPE films buried in natural soil for 90 days was analyzed using x‐ray fluorescence. The study showed an increase in phosphorus and calcium mass percent in the soil. This is due to the decomposition of the hydroxyapatite present in the CFSP/LLDPE biocomposite.

Recycling of waste calcium carbonate in lignocellulosic biorefining chain for chiral lactic acid production

One of the major end-products of lignocellulosic biorefining chain is the solid residues containing various compounds. The present approach to solid residues treatment is combustion for generation of heat and electricity. This study investigated the potential for recycling of the combustion ash from the solid residues after lignocellulosic dry biorefining process. A range of characterizations showed that the combustion ash contained a high amount of calcium carbonate. By recycling the ash as the neutralizer in biorefining process, the waste calcium carbonate in the ash was efficiently utilized for pretreated biomass neutralization and can replace 40 % of calcium hydroxide for lactic acid production. The chiral L-lactic acid titer reached 102.4 ± 3.6 g/L from 20 % (w/w) solids loading of wheat straw. Three feasible strategies of ash recycling for the investigated biorefinery concept were further proposed base on the rigorous calcium mass calculation, which can efficiently reduce the consumption of neutralizers.

The potential role of the aortic valve calcium score by computed tomography scan in the diagnosis of concomitant cardiac amyloidosis in patients with severe aortic stenosis

Abstract Background Cardiac amyloidosis (CA) and aortic stenosis (AS) are two related, but the diagnosis of both these condition is challenging because of the common phenotype. Different predictors of CA in AS have been proposed in the last years. Purpose To identify a new red-flag of concomitant CA in patients with severe AS analyzing aortic valve calcium burden using calcium score, calcium mass and calcium volume by computed tomography scan (CT). Methods 55 patients with severe AS and suspicion of concomitant CA were retrospectively enrolled from 2009 to 2022. 5 Patients with a bicuspid aortic valve, previous aortic valve replacement, or an incomplete diagnostic workup for CA were excluded. 50 patients underwent CT-scan and were included in the final analysis. Results Of the 50 patients, 21 patients (AS-CA) had positive 99m Tc-DPD bone scintigraphy (19 with score 2 and 2 with score 3), none of the patients presented laboratory suspicion for AL amyloidosis, so all the patients had a diagnosis of transthyetin related CA. 29 patients (AS alone) had negative bone scintigraphy. AVA indexed were comparable between AS-CA and AS alone groups (0.3 mm2/m2, in both the group p: 0.88). Stroke volume, maximum and mean gradient were significatively lower in AS-CA group (29 vs 36 ml/m2, p: 0.01, 60 vs 72 mmHg, p: 0.016 and 34 vs 45 mmHg, p:0.01) with a higher percentage of low flow-low gradient aortic stenosis in AS-CA group (11 patients,52% vs 5 patients in AS-alone 17%, p: 0.014)ECG in AS-CA group showed atrial fibrillation in 12 patients (57%), versus 3 patients in the AS-alone group (10%), and lower QRS voltages (peripheral QRS score 44 mV vs 58 mV, p-value:0.017; total QRS score 120 mV versus 160 mV, p-value: 0.005). The echocardiogram showed a more thickened IVS and PW in AS-CA patients (17 versus 15 mm, p: 0.03 and 15 versus 14 mm, p: 0.01) with a decreases longitudinal systolic function (septal S wave at TDI 4.4 vs 5.1 cm/s, p: 0.011, lateral S wave 4.5 versus 5.6 cm/s, p: 0.014).CT- aortic valve calcium was quantified by an experienced operator. A statistically significant difference between AS-CA and AS-alone groups was observed in calcium score (3569 vs 4480 Agatston units, p: 0.017) calcium volume (2575 vs 3445 mm3, p: 0.012) and calcium mass (798 vs 1082 g, p: 0.016).At logistic regression analyses,confirmed perdictors of concomitant CA in AS were: AS low flow- low gradient (p:0.011), atrial fibrillation (p:0.001), lower QRS score periferical(p:0.004) and total (p:0.002) and a decreased longitudinal systolic function (p:0.028). Regarding the aortic valve calcium burden, calcium score( p:0.031) and calcium volume(p:0.026) were confirmed predictor of CA in AS. Conclusions This study shows that calcium burden at CT scan in patients with concomitant CA-AS is significatily lower than in patients with AS alone. Calcium burden at CT scan could be used in addition to the classical parameters as a potential red-flag of concomitant CA in AS severe.

Addition of red tomato extract in feeds using protein sources and calcium microparticles on protein digestibility and meat production in broiler chickens

The study aimed to assess the effect of adding red tomato extract in feeds using protein sources and calcium microparticles on protein digestibility, meat calcium mass, meat protein mass, and meat weight in broiler chickens. Two hundred day-old broiler chicks (Cobb-CP 707) unsexed aged 8 days with an average weight of 169.19 ± 5.67 g. Red tomato extract (RTE) as an antioxidant source. The study used a completely randomized design with 5 treatments and 4 replicates (each 10 birds). The treatments include T0: control feed, T1: T0 + RTE 100 mg/kg, T2: T0 + RTE 200 mg/kg, T3: T0 + RTE 300 mg/kg, and T4: T0 + RTE 400 mg/kg. Parameters measured protein digestibility, meat calcium mass, meat protein mass and meat weight. Data were processed using analysis of variance and Duncan's test in the SPSS version 16 program. The addition of 100-400 mg/kg RTE in feeds using microparticle protein and calcium sources had a significant effect (p&lt;0.05) on protein digestibility, meat calcium mass, meat protein mass and meat weight. The conclusion is that the addition of red tomato extract at 400 mg/kg in feeds using microparticle protein and calcium sources increases protein digestibility, meat calcium mass, meat protein mass and meat weight in broiler chickens.

Quantitative analysis of aortic Na[18F]F uptake in macrocalcifications and microcalcifications in PET/CT scans.

Currently, computed tomography (CT) is used for risk profiling of (asymptomatic) individuals by calculating coronary artery calcium scores. Although this score is a strong predictor of major adverse cardiovascular events, this method has limitations. Sodium [18F]fluoride (Na[18F]F) positron emission tomography (PET) has shown promise as an early marker for atherosclerotic progression. However, evidence on Na[18F]F as a marker for high-risk plaques is limited, particularly on its presentation in clinical PET/CT. Besides, the relationship between microcalcifications visualized by Na[18F]F PET and macrocalcifications detectable on CT is unknown. To establish a match/mismatch score in the aorta between macrocalcified plaque content on CT and microcalcification Na[18F]F PET uptake. Na[18F]F-PET/CT scans acquired in our centre in 2019-2020 were retrospectively collected. The aorta of each low-dose CT was manually segmented. Background measurements were placed in the superior vena cava. The vertebrae were automatically segmented using an open-source convolutional neural network, dilated with 10mm, and subtracted from the aortic mask. Per patient, calcium and Na[18F]F-hotspot masks were retrieved using an in-house developed algorithm. Three match/mismatch analyses were performed: a population analysis, a per slice analysis, and an overlap score. To generate a population image of calcium and Na[18F]F hotspot distribution, all aortic masks were aligned. Then, a heatmap of calcium HU and Na[18F]F-uptake on the surface was obtained by outward projection of HU and uptake values from the centerline. In each slice of the aortic wall of each patient, the calcium mass score and target-to-bloodpool ratios (TBR) were calculated within the calcium masks, in the aortic wall except the calcium masks, and in the aortic wall in slices without calcium. For the overlap score, three volumes were identified in the calcium and Na[18F]F masks: volume of PET (PET+/CT-), volume of CT (PET-/CT+), and overlapping volumes (PET+/CT+). A Spearman's correlation analysis with Bonferroni correction was performed on the population image, assessing the correlation between all HU and Na[18F]F vertex values. In the per slice analysis, a paired Wilcoxon signed-rank test was used to compare TBR values within each slice, while an ANOVA with post-hoc Kruskal-Wallis test was employed to compare TBR values between slices. p-values<0.05 were considered significant. In total, 186 Na[18F]F-PET/CT scans were included. A moderate positive exponential correlation was observed between total aortic calcium mass and total aortic TBR (r=0.68, p<0.001). A strong positive correlation (r=0.77, p<0.0001) was observed between CT values and Na[18F]F values on the population image. Significantly higher TBR values were found outside calcium masks than inside calcium masks (p<0.0001). TBR values in slices where no calcium was present, were significantly lower compared with outside calcium and inside calcium (both p<0.0001). On average, only 3.7% of the mask volumes were overlapping. Na[18F]F-uptake in the aorta behaves similarly to macrocalcification detectable on CT. Na[18F]F-uptake values are also moderately correlated to calcium mass scores (match). Higher uptake values were found just outside macrocalcification masks instead of inside the macrocalcification masks (mismatch). Also, only a small percentage of the Na[18F]F-uptake volumes overlapped with the calcium volumes (mismatch).

Measuring calcium content in plants using NEXAFS spectroscopy.

Calcium is important for the growth and development of plants. It serves crucial functions in cell wall and cell membrane structure and serves as a secondary messenger in signaling pathways relevant to nutrient and immunity responses. Thus, measuring calcium levels in plants is important for studies of plant biology and for technology development in food, agriculture, energy, and forest industries. Often, calcium in plants has been measured through techniques such as atomic absorption spectrophotometry (AAS), inductively coupled plasma-mass spectrometry (ICP-MS), and electrophysiology. These techniques, however, require large sample sizes, chemical extraction of samples or have limited spatial resolution. Here, we used near-edge X-ray absorption fine structure (NEXAFS) spectroscopy at the calcium L- and K-edges to measure the calcium to carbon mass ratio with spatial resolution in plant samples without requiring chemical extraction or large sample sizes. We demonstrate that the integrated absorbance at the calcium L-edge and the edge jump in the fluorescence yield at the calcium K-edge can be used to quantify the calcium content as the calcium mass fraction, and validate this approach with onion epidermal peels and ICP-MS. We also used NEXAFS to estimate the calcium mass ratio in hypocotyls of a model plant, Arabidopsis thaliana, which has a cell wall composition that is similar to that of onion epidermal peels. These results show that NEXAFS spectroscopy performed at the calcium edge provides an approach to quantify calcium levels within plants, which is crucial for understanding plant physiology and advancing plant-based materials.

Impact of Cardiac Motion on coronary artery calcium scoring using a virtual non-iodine algorithm on photon-counting detector CT: a dynamic phantom study.

This study assessed the impact of cardiac motion and in-vessel attenuation on coronary artery calcium (CAC) scoring using virtual non-iodine (VNI) against virtual non-contrast (VNC) reconstructions on photon-counting detector CT. Two artificial vessels containing calcifications and different in-vessel attenuations (500, 800HU) were scanned without (static) and with cardiac motion (60, 80, 100 beats per minute [bpm]). Images were post-processed using a VNC and VNI algorithm at 70keV and quantum iterative reconstruction (QIR) strength 2. Calcium mass, Agatston scores, cardiac motion susceptibility (CMS)-indices were compared to physical mass, static scores as well as between reconstructions, heart rates and in-vessel attenuations. VNI scores decreased with rising heart rate (p < 0.01) and showed less underestimation than VNC scores (p < 0.001). Only VNI scores were similar to the physical mass at static measurements, and to static scores at 60bpm. Agatston scores using VNI were similar to static scores at 60 and 80bpm. Standard deviation of CMS-indices was lower for VNI-based than for VNC-based CAC scoring. VNI scores were higher at 500 than 800HU (p < 0.001) and higher than VNC scores (p < 0.001) with VNI scores at 500 HU showing the lowest deviation from the physical reference. VNI-based CAC quantification is influenced by cardiac motion and in-vessel attenuation, but least when measuring Agatston scores, where it outperforms VNC-based CAC scoring.

Coronary artery calcium mass measurement based on integrated intensity and volume fraction techniques.

Agatston scoring does not detect all the calcium present in computed tomography scans of the heart. A technique that removes the need for thresholding and quantifies calcium mass more accurately and reproducibly is needed. Integrated intensity and volume fraction techniques were evaluated for accurate quantification of calcium mass. Integrated intensity calcium mass, volume fraction calcium mass, Agatston scoring, and spatially weighted calcium scoring were compared with known calcium mass in simulated and physical phantoms. The simulation was created to match a 320-slice CT scanner. Fat rings were added to the simulated phantoms, which resulted in small (), medium (), and large () phantoms. Three calcification inserts of different diameters and hydroxyapatite densities were placed within the phantoms. All the calcium mass measurements were repeated across different beam energies, patient sizes, insert sizes, and densities. Physical phantom images from a previously reported study were then used to evaluate the accuracy and reproducibility of the techniques. Both integrated intensity calcium mass and volume fraction calcium mass yielded lower root mean squared error (RMSE) and deviation (RMSD) values than Agatston scoring in all the measurements in the simulated phantoms. Specifically, integrated calcium mass (RMSE: 0.49mg, RMSD: 0.49mg) and volume fraction calcium mass (RMSE: 0.58mg, RMSD: 0.57mg) were more accurate for the low-density stationary calcium measurements than Agatston scoring (RMSE: 3.70mg, RMSD: 2.30mg). Similarly, integrated calcium mass (15.74%) and volume fraction calcium mass (20.37%) had fewer false-negative (CAC = 0) measurements than Agatston scoring (75.00%) and spatially weighted calcium scoring (26.85%), on the low-density stationary calcium measurements. The integrated calcium mass and volume fraction calcium mass techniques can potentially improve risk stratification for patients undergoing calcium scoring and further improve risk assessment compared with Agatston scoring.

Protein deposition and carcass weight in broiler given noni fruit extract (Morinda citrifolia L.) compared to zinc bacitracin

The purpose of the study was to examine the effect of giving noni fruit extract (Morinda citrifolia L.) compared to zinc bacitracin to broiler chickens on total lactic acid bacteria, coliform bacteria, small intestine pH, protein digestibility, meat calcium mass, meat protein mass and carcass weight. This research used 200 unsexed broiler chickens of Cobb MB 202 aged 15 days with an average body weight of 246.02 ± 11.31 g. The study used a completely randomized design with 5 treatments and 4 replicates (each 10 bird). The treatments include T0: ration (control), T1: T0 + 0.04% zinc bacitracin, T2: T0 + 0.04% noni fruit extract, T3: T0 + 0.08% noni fruit extract, T4: T0 + 0.12% noni fruit extract. Parameters measured included total lactic acid bacteria, coliform bacteria, small intestine pH, protein digestibility, meat calcium mass, meat protein mass and carcass weight. Data were processed using analysis of variance and Duncan's test in the SPSS version 16 program. The results showed that the provision of noni fruit extract had a significant effect (p&lt;0.05) on all parameters measured. The study concludes that the feeding of noni fruit extract at 0.12% can be used as a substitute for zinc bacitracin by increasing total lactic acid bacteria, protein digestibility, calcium mass, meat protein, carcass weight but reduce pH and total small intestine coliform in broiler chickens.

#2531 AGATSTON INDEX AS A PREDICTOR OF PREDICTION OF THE DEGREE OF HEART VASCULAR DAMAGE IN STAGE 5 CKD PATIENTS RECEIVING PROGRAM HEMODIALYSIS

Abstract Background and Aims Cardiovascular events (CVEs) are the leading cause of death in patients with chronic kidney disease (CKD). A retrospective analysis of the causes of death of a large group of nephrological patients shows that the mortality of patients from cardiovascular events is more than 4.1 higher than the number of deaths from all kidney diseases, including end-stage chronic kidney disease [1]. Aim of the study: to evaluate the possibility of CI for predicting the degree of damage to the coronary arteries of the heart in patients with CKD. Method In a prospective study for MSCT, 60 patients were selected (30 patients each from groups 1 and 2 (15 patients in subgroups) with CKD stage 5 of various etiologies receiving PG. The results of multispiral CT-coronary angiography in 60 consecutive patients/clients of a multidisciplinary clinic were analyzed. Among them were: 41 men (68.3%) and 19 women (31.6), the age ranged from 28 to 74 years (mean age - 53.4 ± 11.89 years). The mean age of the woman was 55.05 ± 11.92 years; men 52.63 ± 11.61 years old, there were no statistically significant differences between the age, heart rate, SBP and DBP of women and men, which indicates the representativeness of the groups. Results To assess coronary calcification, MSCT of the chest was performed to determine the mass and volume of coronary calcium. When compared in group 1 patients, in relation to group 2 patients in all coronary basins, there is a significant increase in the content of coronary calcium (p&amp;lt;0.05 for all indicators). The Agatston index in the examined patients ranged from 0 to 790 units (units). Patients with CI ranging from 101 to 400 units. were older - from 34 to 54 years (mean age 42.77 years). Among them, males clearly predominated. In 50% of patients, there was a multivascular lesion of the coronary arteries with significant stenosis in the anterior interventricular branch (LAD) and the right coronary artery (RCA), and without significant stenosis in the circumflex branch of the left coronary artery. With CI over 400 units. all 30 examined patients had multiple coronary artery stenoses, the maximum of which exceeded 70%. At the same time, 5 patients (8.3%) had 4 stenoses of the coronary arteries of the heart. This is consistent with evidence that increased cardiovascular risk is associated with total coronary artery calcium load. Taking into account the fact that according to the results of the study it was found that in many patients with coronary artery stenosis from 20 to 49%, belonging to the group of patients with high cardiovascular risk and with stenosis of more than 50%, to the group of very high risk, having an increased CI, then this indicator can be used as an additional indicator for cardiovascular risk stratification to predict cardiovascular events. Conclusion The Agatston index or CI, determined using multislice CT, can be used as a screening method for detecting coronary artery atherosclerosis and determining cardiovascular risk. With CI over 100 units. the vast majority of the surveyed revealed multiple stenoses of the coronary arteries, with an indicator of more than 400 units. hemodynamically significant arterial damage is expected. Such patients should undergo an additional examination: functional tests (bicycle ergometry, treadmill test, daily ECG monitoring) or contrast coronary angiography to verify the main diagnosis and to decide on further tactics for managing patients.

Integrated intensity-based technique for coronary artery calcium mass measurement: A phantom study.

Agatston scoring, the traditional method for measuring coronary artery calcium, is limited in its ability to accurately quantify low-density calcifications, among other things. The inaccuracy of Agatston scoring is likely due partly to the arbitrary thresholding requirement of Agatston scoring. A calcium quantification technique that removes the need for arbitrary thresholding and is more accurate, sensitive, reproducible, and robust is needed. Improvements to calcium scoring will likely improve patient risk stratification and outcome. The integrated Hounsfield technique was adapted for calcium scoring (integrated calcium mass). Integrated calcium mass requires no thresholding and includes all calcium information within an image. This study utilized phantom images acquired by G van Praagh etal., with calcium hydroxyapatite (HA) densities in the range of 200-800mgHAcm-3 to measure calcium according to integrated calcium mass and Agatston scoring. The calcium mass was known, which allowed for accuracy, reproducibility, sensitivity, and robustness comparisons between integrated calcium mass and Agatston scoring. Multiple CT vendors (Canon, GE, Philips, Siemens) were used during the image acquisition phase, which provided a more robust comparison between the two calcium scoring techniques. Three calcification inserts of different diameters (1, 3, and 5mm) and different HA densities (200, 400, and 800 mgHAcm-3 ) were placed within the phantom. The effect of motion was also analyzed using a dynamic phantom. All dynamic phantom calcium inserts were 5.0±0.1mm in diameter with a length of 10.0±0.1mm. The four different densities were 196±3, 380±2, 408±2, and 800±2mgHAcm-3 . Integrated calcium mass was more accurate than Agatston scoring for stationary scans ( , ) and motion affected scans ( , ). On average, integrated calcium mass was more reproducible than Agatston scoring for two of the CT vendors. The percentage of false-negative and false-positive calcium scores were lower for integrated calcium mass (15.00%, 0.00%) than Agatston scoring (28.33%, 6.67%). Integrated calcium mass was more robust to changes in scan parameters than Agatston scoring. The results of this study indicate that integrated calcium mass is more accurate, reproducible, and sensitive than Agatston scoring on a variety of different CT vendors. The substantial reduction in false-negative scores for integrated calcium mass is likely to improve risk-stratification for patients undergoing calcium scoring and their potential outcome.

Bioavailability of calcium in an enriched postbiotic system compared to calcium citrate in healthy postmenopausal females; A randomized, double-blind, comparator-controlled, crossover study.

Bioavailability of calcium is an important consideration when designing supplements for achieving adequate calcium intake, mainly in high-risk, and aged populations. Alternative supplementation strategies may be able to circumvent absorption issues commonly seen with calcium supplements. The objective of this study was to assess the bioavailability of a single serving of two calcium formulations vs. comparator product in healthy postmenopausal women. A total of 24 participants between 45 and 65 years were enrolled in a randomized, double-blind, three-phase, crossover study, with a 7-day washout period between phases. The bioavailability of calcium from calcium-carrying Saccharomyces cerevisiae (Ca-SC) or calcium-carrying Lactobacillus (Ca-LAB) in the form of postbiotic products versus calcium citrate, a conventional salt-based calcium supplement, was determined. Each product provided 630 mg of calcium and 400 IU of vitamin D3. After a 14-h (overnight) fast followed by a single dose of product with a standard low-calcium breakfast, both serum and urine calcium concentrations were assessed for up to 8 and 24 h, respectively. Ca-LAB resulted in greater calcium bioavailability, demonstrated by significantly higher area under the curve and peak concentration both in blood and urine, and total calcium mass excreted in urine. The bioavailability of calcium was similar for Ca-SC and calcium citrate except for the peak concentration value that was significantly higher for calcium citrate. Both Ca-LAB and Ca-SC were well tolerated with no significant difference in adverse events between the products during the study. These findings suggest that calcium enriched in a Lactobacillus-based postbiotic system is associated with higher levels of bioavailability as compared to calcium citrate, while a calcium-enriched yeast-based postbiotic does not influence calcium absorption.

A Novel Low Molecule Peptides-calcium Chelate from Silkworm Pupae Protein Hydrolysate: Preparation, Antioxidant Activity, and Bioavailability.

The antioxidant properties of active peptides from silkworm pupae protein hydrolysate are of interest, and it serves as a novel source of calcium supplement. Optimize the preparation parameters of silkworm pupae bioactive peptide-calcium chelate, and investigate the mechanism and bioavailability of silkworm pupae active peptide as a transport carrier to promote calcium ion absorption using simulated gastrointestinal digestion and Caco-2 monolayer cell model. The optimal process parameters for preparing peptide calcium chelate were the peptide calcium mass ratio of 3:1, pH of 6.7, a temperature of 35.6°C, and time of 32.8 min by Box-Behnken design, and the calciumchelating rate reached 84.67%. The DPPH radical scavenging activity of silkworm pupae protein hydrolysatecalcium chelate was 79.36 ± 4.31%, significantly higher than silkworm pupae protein hydrolysate (61.00 ± 9.56%). Fourier transform infrared spectroscopy shows that the COO-, N-H, C-H, and C-O groups participated in the formation of silkworm pupae protein hydrolysate-calcium chelate. The particle size of the silkworm pupae protein hydrolysate-calcium chelate was 970.75 ± 30.12 nm, which was significantly higher than that of silkworm pupae protein hydrolysate (253.14 ± 5.72 nm). The silkworm pupae protein hydrolysate-calcium chelate showed a calcium dissolution rate of 71.01 ± 1.91% in the simulated intestinal phase, significantly higher than that of CaCl2 (59.34 ± 1.24%). In the Caco-2 cell monolayers, the silkworm pupae protein hydrolysatecalcium chelate was more favorable for calcium transport. A novel silkworm pupa protein hydrolysate-calcium chelate with high antioxidant activity was successfully prepared to improve the bioavailability of calcium.

Abstract P678: On the Relationship of Breast Arterial Calcification With Coronary Artery Calcification: A Pilot Study

Breast arterial calcification (BAC) detected in mammograms is an emerging risk-enhancing factor for atherosclerotic cardiovascular disease (ASCVD). The predictive value of coronary artery calcification (CAC) for risk of ASCVD above and beyond traditional risk factors is well-established in women. However, there are few studies that have simultaneously evaluated BAC and CAC. The Multiethnic study of breast arterial calcium gradation and cardiovascular disease (MINERVA) cohort, a large, racially and ethnically diverse cohort of postmenopausal women aged 60-69 (n=5,059) was recruited in 2012-15 at Kaiser Permanente of Northern California (KPNC). BAC was assessed using a densitometry method, and presence of BAC was defined as a calcium mass score&gt;0 mg. Searching the electronic health record up to 5 years after baseline, we identified 33 women (39% non-white) who underwent cardiac computed tomography (CT) because of medical indication. BAC was present in 33% (11/33) whereas CAC (Agastston score &gt;0) was present in 61% (20/33). Nine (27%) were BAC and CAC -; 7 (21%) were BAC and CAC+; 4 (12%) were BAC+ and CAC -; and 13 (39%) were BAC - and CAC+. The correlation between log (BAC+1) and log (CAC+1) was 0.45 (p=0.02) in the entire sample (n=33) and was 0.68 (p=0.09) in the 7 women who were BAC and CAC+. The concordance, sensitivity, specificity, PPV, NPV for BAC considering CAC as the gold standard were 0.48, 0.35, 0.69, 0.63 and 0.41, respectively. The unadjusted odds ratio for log (CAC+1)&gt;0 as a function of Log (BAC+1) was 1.21 (95% CI, 0.27-5.38; p=0.80). Although our sample was small, the findings reflect real-world evidence and suggest that BAC and CAC are not entirely overlapping and thus may convey independent predictive information for ASCVD.

Fouling characterization and treatment of water reuse concentrate with membrane distillation: Do organics really matter

Membrane distillation (MD) for the treatment of concentrated brines has been limited in part by membrane fouling, resulting in subsequent flux decline and membrane wetting. This study provides new insight into the identification of fouling and scaling mechanisms and pretreatment strategies for mitigating flux decline with MD treatment of water reuse reverse osmosis concentrate (ROC). Bench-scale direct contact MD experiments were performed with untreated and pretreated ROC. Biological activated carbon (BAC), chemical water softening, or fluidized bed crystallization reactor coupled with ion exchange (FBCR-IX) were selected as pretreatment strategies to isolate the effects of organic fouling and calcium scaling. Organic and inorganic compounds were analyzed by high-performance liquid chromatography (HPLC) and inductively coupled plasma mass spectrometry (ICP-MS). Calcium ions were found to be the major contributor to flux decline despite the high organic content in the ROC. Minimal organic fouling is likely because the organic matter in the ROC is hydrophilic, limiting hydrophobic-hydrophobic interactions between the organics and the membrane. Furthermore, the water flux declined by 63 % after removing organic compounds by BAC pretreatment, with 60 % of the calcium mass precipitating from the solution. Whereas, the water flux remained constant after removing multivalent ions with fluidized bed crystallization. Cleaning the membrane by acid washing and temperature reversal recovered 73 % and 12 % of the water flux, respectively. The analyses outlined in this study can assist in selecting appropriate fouling and scaling mitigation strategies for water reuse ROC and a wide range of feed solutions used in MD applications.

Vessel-by-Vessel Computed Tomography Calcium Scoring of the Foot in Peripheral Artery Disease: Association with Patient-Level Factors.

Objective: Peripheral artery disease (PAD) is associated with increased risk of nonhealing ulcers, amputation, and mortality due to occlusive atherosclerotic plaques. Computed tomography (CT) imaging detects vascular calcification in PAD; however, quantitative vessel-by-vessel analysis of calcium burden in the feet of PAD patients has not been assessed. This study sought to perform quantitative analysis of vessel-specific calcium burden and examine the patient-level determinants of foot calcium burden in PAD patients. Approach: PAD patients (n = 41) were prospectively enrolled and underwent CT imaging of the lower extremities. Manual segmentation of the medial plantar, lateral plantar, and dorsalis pedis arteries was performed. CT image Hounsfield units (HUs) were obtained for each artery to quantify vessel-by-vessel calcium mass using a cutoff value of ≥130 HU. Univariate analyses were performed to evaluate patient-level determinants of calcium burden for each foot artery. STROBE guidelines were used for reporting of data. Results: Univariate analyses revealed that body mass index, diabetes mellitus (DM), and chronic kidney disease (CKD) were significant determinants of foot calcium burden in PAD patients. Image analysis demonstrated that PAD patients with DM had significantly higher calcium mass for the medial plantar (p = 0.005), lateral plantar (p = 0.039), and dorsalis pedis (p = 0.001) arteries compared with PAD patients without DM. Innovation: This is the first study to use CT imaging to quantify vessel-specific calcium burden in the feet of patients with PAD and evaluate the patient-level determinants of foot calcium burden in the setting of PAD. Conclusion: CT imaging quantifies vessel-specific calcification in the feet of PAD patients, which is exacerbated with concomitant DM, CKD, and/or obesity.