Crystal Inhibition Research Articles

Isothermal crystallization of anhydrous milk fat in presence of free fatty acids and their esters: From nanostructure to textural properties

We performed a multiscale study to understand the impact of pure exogenous compounds at low concentration on the crystallization of triacylglycerols (TAGs) in anhydrous milk fat (AMF). We selected butyric acid, an inhibitor of crystallization, and palmitic acid, a promotor, to investigate the influence of the chain length. Tripalmitin was also used as a promotor to assess the impact of fatty acid esterification. Melted blends containing the additives (1 wt%) were quenched at 25 °C. X-ray scattering data showed that AMF TAGs crystallized directly in the β’-2L form. The presence of additives did not modify the nanostructure of TAG crystals. However, they significantly altered the microstructure of AMF, as revealed by polarized light microscopy and rheology. This study emphasizes the interest of a multiscale approach to gain knowledge about the behavior of complex fat blends and of the use of modulators at low concentration to monitor their textural properties.

Seeking consistency for the role of urinary macromolecules and glycosaminoglycans in calcium oxalate crystallization processes pertaining to the risk of renal stone formation using a multi-faceted basic science approach

BackgroundThe roles of urinary macromolecules (UMMs) in calcium oxalate (CaOx) renal stone formation have not been consistently established. AimTo unravel these roles using a multi-faceted, multi-technique approach employing a wide range of experimental variables on a rotational basis in strategically chosen combinations. MethodsEndogenous urinary glycosaminoglycans (GAGs) were investigated in fractions obtained after ultrafiltration of pooled human urine (HU). Exogenous GAGs (chondroitin sulphate, CS, and hyaluronic acid, HA) were studied in artificial (AU) and in individual HUs. Experiments were conducted in a batch crystallizer and in a mixed suspension, mixed product removal flow system. Crystallization was quantitatively followed using Coulter multisizer and flow cytometer techniques. Crystal aggregation in the presence and absence of exogenous CS and HA was measured by Zeta potential and crystal sedimentation. ResultsTotal UMMs (endogenous) and individual GAGs (exogenous) consistently promoted CaOx crystallization and disaggregation. Evidence of UMM-UMM and UMM-solution synergistic effects was consistently observed for achieving modulation of crystallization processes. ConclusionsTotal UMMs, the main modulatory component of which is GAGs, are promoters of CaOx crystal nucleation and inhibitors of CaOx crystal aggregation. These results allow researchers to disregard alternative roles that have been advocated in such studies.

Polyaminoacids in Biomimetic Collagen Mineralization: Roles of Isomerization and Disorder in Polyaspartic and Polyglutamic Acids.

The extracellular matrix of hard connective tissues is composed primarily of mineralized collagen fibrils. Acidic noncollagenous proteins play important roles in mediating mineralization of collagen. Polyaspartate, a homopolymer substitute for such proteins, has been used extensively in in vitro models to produce biomimetic mineralized collagen. Polyglutamate behaves differently in mineralization models, despite its chemical similarity. We show that polyaspartate is a 350 times more effective inhibitor of solution precipitation of hydroxyapatite than polyglutamate. Supersaturated CaP solutions stabilized with polyaspartic acid produce collagen with aligned intrafibrillar mineral, while solutions containing polyglutamate lead to the formation of unaligned mineral clusters on the fibril surface. Molecular analysis showed that the commercial polyaspartic acid contains substantial isomerization, unlike polyglutamic acid. Hence, the secondary structure of polyaspartic acid is more disordered than that of polyglutamic acid. The increased flexibility of the polyaspartic acid chain may explain its potency as an inhibitor of solution crystallization and a mediator of intrafibrillar collagen mineralization.

Molecular insight into isoform specific inhibition of PI3K-\u03b1 and PKC-\u03b7 with dietary agents through an ensemble pharmacophore and docking studies

Dietary compounds play an important role in the prevention and treatment of many cancers, although their specific molecular mechanism is not yet known. In the present study, thirty dietary agents were analyzed on nine drug targets through in silico studies. However, nine dietary scaffolds, such as silibinin, flavopiridol, oleandrin, ursolic acid, α-boswellic acid, β-boswellic acid, triterpenoid, guggulsterone, and oleanolic acid potentially bound to the cavity of PI3K-α, PKC-η, H-Ras, and Ras with the highest binding energy. Particularly, the compounds silibinin and flavopiridol have been shown to have broad spectrum anticancer activity. Interestingly, flavopiridol was embedded in the pockets of PI3K-α and PKC-η as bound crystal inhibitors in two different conformations and showed significant interactions with ATP binding pocket residues. However, complex-based pharmacophore modeling achieved two vital pharmacophoric features namely, two H-bond acceptors for PI3K-α, while three are hydrophobic, one cat-donor and one H-bond donor and acceptor for PKC-η, respectively. The database screening with the ChemBridge core library explored potential hits on a valid pharmacophore query. Therefore, to optimize perspective lead compounds from the hits, which were subjected to various constraints such as docking, MM/GBVI, Lipinski rule of five, ADMET and toxicity properties. Henceforth, the top ligands were sorted out and examined for vital interactions with key residues, arguably the top three promising lead compounds for PI3K-α, while seven for PKC-η, exhibiting binding energy from − 11.5 to − 8.5 kcal mol−1. Therefore, these scaffolds could be helpful in the development of novel class of effective anticancer agents.

Drug crystal growth in ternary amorphous solid dispersions: Effect of surfactants and polymeric matrix-carriers

The present study evaluates the crystal growth rate of amorphous drugs when dispersed in different ternary polymeric amorphous solid dispersions (ASDs) in the presence of surfactants. Specifically, ternary ASDs of aprepitant (APT, selected as a model drug) were prepared via melt-quench cooling by evaluating three commonly used ASDs matrix/carriers, namely hydroxypropyl cellulose (HPC), poly(vinylpyrrolidone) (PVP) and the copolymer Soluplus® (SOL), and two suitable surfactants, namely d-alpha tocopheryl polyethylene glycol 1000 succinate (TPGS) and poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P407). Results showed that all components were completely miscible (verified via hot stage polarized microscopy) and both surfactants were acting as plasticizers to the API. APT's crystal growth rate was increased in the presence of both P407 and TPGS, while PVP was identified as the matrix/carrier with the greatest impact API's crystal growth rate inhibition. Interestingly, TPGS presented a noticeable synergistic effect when combined with PVP resulting in a further reduction of APT's crystal growth rate. Furthermore, evaluation of APT's nucleation induction time in dissolution medium (PBS pH 6.8) revealed PVP as the most effective crystallization inhibitor, whereas the addition of TPGS showed to improve PVP's ability to inhibit APT's recrystallization. Finally, the formation of intermolecular interactions in the ternary APT-PVP-TPGS provided an explanation for the observed PVP-TPGS synergistic effects, with molecular dynamics simulations being able to unravel the type and extent of these interactions on a theoretical basis.

Human kidney stones: a natural record of universal biomineralization.

GeoBioMed - a new transdisciplinary approach that integrates the fields of geology, biology and medicine - reveals that kidney stones composed of calcium-rich minerals precipitate from a continuum of repeated events of crystallization, dissolution and recrystallization that result from the same fundamental natural processes that have governed billions of years of biomineralization on Earth. This contextual change in our understanding of renal stone formation opens fundamentally new avenues of human kidney stone investigation that include analyses of crystalline structure and stratigraphy, diagenetic phase transitions, and paragenetic sequences across broad length scales from hundreds of nanometres to centimetres (five Powers of 10). This paradigm shift has also enabled the development of a new kidney stone classification scheme according to thermodynamic energetics and crystalline architecture. Evidence suggests that ≥50% of the total volume of individual stones have undergone repeated in vivo dissolution and recrystallization. Amorphous calcium phosphate and hydroxyapatite spherules coalesce to form planar concentric zoning and sector zones that indicate disequilibrium precipitation. In addition, calcium oxalate dihydrate and calcium oxalate monohydrate crystal aggregates exhibit high-frequency organic-matter-rich and mineral-rich nanolayering that is orders of magnitude higher than layering observed in analogous coral reef, Roman aqueduct, cave, deep subsurface and hot-spring deposits. This higher frequency nanolayering represents the unique microenvironment of the kidney in which potent crystallization promoters and inhibitors are working in opposition. These GeoBioMed insights identify previously unexplored strategies for development and testing of new clinical therapies for the prevention and treatment of kidney stones.

The Amorphous Quercetin/ Hydroxypropylmethylcellulose Acetate Succinate Solid Dispersions Prepared by Co-Precipitation Method to Enhance Quercetin Dissolution.

HPMCAS-HF, HPMCAS-MF and HPMCAS-LF were used as carriers to prepare the amorphous solid dispersions (ASDs) of quercetin (Que) by co-precipitation. The Que ASD based on PVP K30 was prepared by solvent evaporation method. The ability of polymer to inhibit Que crystallization was evaluated. The study found the order of the ability of polymer to inhibit Que nucleation to be: HF > MF > LF > K30, and that to maintain Que supersaturation to be: HF > K30 > MF > LF. The prepared solid dispersions were characterized by IR, DSC and PXRD. Although HF was the most effective crystallization inhibitor, the release of the Que/HF ASD was poor and assigned to the carrier-controlled dissolution for the strong interactions between Que and HF. The Que/MF ASD exhibited better dissolution behavior compared to the Que/K30 ASD. The dissolution behavior of the Que ASD depended on the polymer-Que interactions and the ability of crystallization inhibition of the polymer.

Modeling of the synthesis conditions impact on the structure of calcium magnesium phosphates

Calcium magnesium phosphates are widely used as bioceramics, sorbents, catalysts, cement, etc. Herein, calcium magnesium phosphates were obtained by chemical precipitation from a solution using dolomite as a source of calcium and magnesium, hydroxyethylidene diphosphonic acid as an inhibitor of crystallization. The chemical composition of synthesized samples was characterized with a molar ratio (Ca + Mg)/P of 1.29–1.52 and Mg/(Mg + Ca) of 0.54–0.65. The effect of various parameters (solution temperature, precipitator addition rate, duration of precipitate aging, solution addition sequence, and method of precipitation washing) on the chemical and phase composition, texture, and morphology of calcium magnesium phosphates by X-ray diffraction, Fourier transform infra-red spectroscopy, differential-thermal and thermogravimetric analyses, N2 adsorption-desorption, scanning electron microscopy, and fractional factorial experiments were studied. It was established that (i) the hydroxyethylidene diphosphonic acid addition, (ii) the sequence of adding reaction solutions, and (iii) the method of precipitation washing had the greatest influence on the chemical and phase composition of the obtained samples. The surface area and pore volume of calcium magnesium phosphates were significantly increased by the introduction of hydroxyethylidene diphosphonic acid up to 265 m2/g and 0.568 cm3/g, which makes it possible to obtain materials with a developed mesoporous structure for adsorptions application.

Stabilization mechanism of amorphous carbamazepine by transglycosylated rutin, a non-polymeric amorphous additive with a high glass transition temperature

α-Glycosyl rutin (Rutin-G), composed of a flavonol skeleton and sugar groups, is a promising non-polymeric additive for stabilizing amorphous drug formulations. In this study, the mechanism of the stabilization of the amorphous state of carbamazepine (CBZ) by Rutin-G was investigated. In comparison with hypromellose (HPMC), which is commonly used as a crystallization inhibitor for amorphous drugs, Rutin-G significantly stabilized amorphous CBZ. Moreover, the dissolution rate and the resultant supersaturation level of CBZ were significantly improved in the CBZ/Rutin-G spray-dried samples (SPDs) owing to the rapid dissolution property of Rutin-G. Differential scanning calorimetry measurement demonstrated a high glass transition temperature (Tg) of 186.4°C corresponding to Rutin-G. The CBZ/Rutin-G SPDs with CBZ weight ratios up to 80% showed single glass transitions, indicating the homogeneity of CBZ and Rutin-G. A solid-state NMR experiment using 13C- and 15N-labeled CBZ demonstrated the interaction between the flavonol skeleton of Rutin-G and the amide group of CBZ. A 1H-13C two-dimensional heteronuclear correlation NMR experiment and quantum mechanical calculations confirmed the presence of a possible hydrogen bond between the amino proton in CBZ and the carbonyl oxygen in the flavonol skeleton of Rutin-G. This specific hydrogen bond could contribute to the strong interaction between CBZ and Rutin-G, resulting in the high stability of amorphous CBZ in the CBZ/Rutin-G SPD. Hence, Rutin-G, a non-polymeric amorphous additive with high Tg, high miscibility with drugs, and rapid and pH-independent dissolution properties could be useful in the preparation of amorphous formulations.

Discovering the antiurolithiatic potential of wild himalayan cherry through in vitro and preclinical investigations

Prunus cerasoides D. Don is a plant of great venerative value in the Himalayan region. The fruits and seed kernels of this plant are traditionally used for the treatment of urinary stones. Present study was aimed to demonstrate the in vitro and preclinical antilithic potential of the hydroethanolic extract of Prunus cerasoides fruits against calcium oxalate urolithiasis. In vitro antiurolithiatic screening was done by nucleation, and aggregation assay, while preclinical evaluation was carried out on ethylene glycol (0.75% v/v) and ammonium chloride (1% w/v) rendered urolithiasic male Wistar rats. P. cerasoides fruit extract induced nucleation of multiple small sized calcium oxalate crystals and inhibited their aggregation in the metastable solutions. P. cerasoides fruit extract to a large extent prevented lithogenic treatment induced anorexia, weight loss, polydipsia, polyuria, crystalluria, hypercalciuria, hyperoxaluria, hyperuricosuria, hyperphosphaturia, hypocitraturia and hypomagnesuria. It also showed preventive effect on the deposition of calcium, oxalate and phosphate in kidney tissues and exhibited ameliorative effect on serum urea, creatinine and uric acid. Moreover, inhibitory effect on oxidative stress induced degeneration of renal tissue was also recorded from histopathological analysis of the kidneys. PCFE showed promising outcomes as an antiurolithiatic both prophylactically and curatively. The effects can be attributed to its ability to restore the equilibrium between the urinary promoters and inhibitors of CaOx crystallization, its anticrystallization activity and its ameliorating effects on renal cellularity, urine and serum chemistry.

Crystallization of Sodium Bicarbonate in the Presence of Trace Amounts of HPMA

AbstractThe effect of trace amounts of hydrolytic polymaleic anhydride (HPMA) on the crystallization of sodium bicarbonate (NaHCO3) has been investigated by molecular simulation and experimental methods. Cooling crystallization experiments show that the trace HPMA molecule effectively promotes the formation of larger NaHCO3 crystals. Besides, the crystal morphology changes from needle‐like to flake‐like. The determination of the metastable zone width of NaHCO3 and Atomic Force Microscopy (AFM) observation confirmed that the spontaneous nucleation processes are suppressed. Molecule simulation was used to explore the interaction of HPMA molecule and different crystal faces of NaHCO3. It was found that the binding energy between HPMA and NaHCO3 surface is greater than the corresponding attachment energy of NaHCO3 surface. The electrostatic interaction energy between double‐bonded oxygen on the HPMA molecule and the Na+ of the NaHCO3 crystal plane plays a dominant role in the additive molecule‘s adsorption on the NaHCO3 crystal surface. This work suggests that HPMA could serve as an inhibitor of nucleation and impact NaHCO3 crystallization.

Designing a\xa0next generation solar crystallizer for real seawater brine treatment with zero liquid discharge

Proper disposal of industrial brine has been a critical environmental challenge. Zero liquid discharge (ZLD) brine treatment holds great promise to the brine disposal, but its application is limited by the intensive energy consumption of its crystallization process. Here we propose a new strategy that employs an advanced solar crystallizer coupled with a salt crystallization inhibitor to eliminate highly concentrated waste brine. The rationally designed solar crystallizer exhibited a high water evaporation rate of 2.42 kg m−2 h−1 under one sun illumination when treating real concentrated seawater reverse osmosis (SWRO) brine (21.6 wt%). The solar crystallizer array showed an even higher water evaporation rate of 48.0 kg m−2 per day in the outdoor field test, suggesting a great potential for practical application. The solar crystallizer design and the salt crystallization inhibition strategy proposed and confirmed in this work provide a low-cost and sustainable solution for industrial brine disposal with ZLD.

Interaction of Polymers with Enzalutamide Nanodroplets-Impact on Droplet Properties and Induction Times.

Amorphous solid dispersions (ASDs), which consist of a drug dispersed in a polymeric matrix, are increasingly being applied to improve the in vivo performance of poorly water-soluble drugs delivered orally. The polymer is a critical component, playing several roles including facilitating drug release from the ASD, as well as delaying crystallization from the supersaturated solution generated upon dissolution. Certain ASD formulations dissolve to produce amorphous drug-rich nanodroplets. The interaction of the polymer with these nanodroplets is poorly understood but is thought to be important for inhibiting crystallization in these systems. In this study, the impact of ionic polymers on the crystallization kinetics of enzalutamide from supersaturated solutions containing different amounts of amorphous nanodroplets was evaluated by determination of nucleation induction times. The amount of the polymer associated with the drug nanodroplets was also determined. When comparing two polymers, hydroxypropylmethyl cellulose acetate succinate (HPMCAS) and Eudragit E PO, it was found that the crystallization tendency and physical properties of the drug nanodroplets varied in the presence of these two polymers. Both polymers distributed between the aqueous phase and the drug-rich nanodroplets. A greater amount of Eudragit E PO was associated with the drug-rich nanodroplets. Despite this, Eudragit E PO was a less-effective crystallization inhibitor than HPMCAS in systems containing nanodroplets. In conclusion, in supersaturated solutions containing amorphous nanodroplets, the extent of association of a polymer with the drug nanodroplet does not solely predict crystallization inhibition.

Artemisinin-Based Drugs Target the Plasmodium falciparum Heme Detoxification Pathway.

Artemisinin (ART)-based antimalarial drugs are believed to exert lethal effects on malarial parasites by alkylating a variety of intracellular molecular targets. Recent work with live parasites has shown that one of the alkylated targets is free heme within the parasite digestive vacuole, which is liberated upon hemoglobin catabolism by the intraerythrocytic parasite, and that reduced levels of heme alkylation occur in artemisinin-resistant parasites. One implication of heme alkylation is that these drugs may inhibit parasite detoxification of free heme via inhibition of heme-to-hemozoin crystallization; however, previous reports that have investigated this hypothesis present conflicting data. By controlling reducing conditions and, hence, the availability of ferrous versus ferric forms of free heme, we modify a previously reported hemozoin inhibition assay to quantify the ability of ART-based drugs to target the heme detoxification pathway under reduced versus oxidizing conditions. Contrary to some previous reports, we find that artemisinins are potent inhibitors of hemozoin crystallization, with effective half-maximal concentrations approximately an order of magnitude lower than those for most quinoline-based antimalarial drugs. We also examine hemozoin and in vitro parasite growth inhibition for drug pairs found in the most commonly used ART-based combination therapies (ACTs). All ACTs examined inhibit hemozoin crystallization in an additive fashion, and all but one inhibit parasite growth in an additive fashion.

Principal Component Analysis (PCA) Combined with Naturally Occurring Crystallization Inhibitors: An Integrated Strategy for a more Sustainable Control of Salt Decay in Built Heritage

Salt inhibitors have been receiving increasing attention as potential innovative systems to counteract salt damage by preventing crystallisation of the salts within the natural stone structure—and related disruptive action—of built heritage. Especially, we focus on biomass-derived inhibitor systems featuring complete solubility in water or alcohol and intrinsic non-toxicity. Moving from the promising results obtained, the present study aims to develop research concerning the possibility of rationalizing the collected data sets and making them amenable to statistical analysis. This paper reports on an exploratory application of one of the most powerful methods in chemometrics, i.e., principal component analysis (PCA), in this area. It will be seen that this method is a promising tool to extract information from a series of tests to optimize them and to reduce the level of “noise” present in the data collected, i.e., unnecessary information or experimental errors, and to suggest new directions.

A second mechanism employed by artemisinins to suppress Plasmodium falciparum hinges on inhibition of hematin crystallization

Malaria is a pervasive disease that affects millions of lives each year in equatorial regions of the world. During the erythrocytic phase of the parasite life cycle, Plasmodium falciparum invades red blood cells, where it catabolizes hemoglobin and sequesters the released toxic heme as innocuous hemozoin crystals. Artemisinin (ART)-class drugs are activated in vivo by newly released heme, which creates a carbon-centered radical that markedly reduces parasite density. Radical damage to parasite lipids and proteins is perceived to be ARTs’ dominant mechanism of action. By contrast, quinoline-class antimalarials inhibit the formation of hemozoin and in this way suppress heme detoxification. Here, we combine malaria parasite assays and scanning probe microscopy of growing β-hematin crystals to elucidate an unexpected mechanism employed by two widely administered antimalarials, ART, and artesunate to subdue the erythrocytic phase of the parasite life cycle. We demonstrate that heme–drug adducts, produced after the radical activation of ARTs and largely believed to be benign bystanders, potently kills P. falciparum at low exogenous concentrations. We show that these adducts inhibit β-hematin crystallization and heme detoxification, a pathway which complements the deleterious effect of radicals generated via parent drug activation. Our findings reveal an irreversible mechanism of heme–ART adduct inhibition of heme crystallization, unique among antimalarials and common crystal growth inhibitors, that opens new avenues for evaluating drug dosing regimens and understanding growing resistance of P. falciparum to ART.

Rubidium Ions Enhanced Crystallinity for Ruddlesden-Popper Perovskites.

Tailoring the organic spacing cations enables developing new Ruddlesden–Popper (RP) perovskites with tunable optoelectronic properties and superior stabilities. However, the formation of highly crystallized RP perovskites can be hindered when the structure of organic cations become complex. Strategies to regulate crystal growing process and grains quality remain to be explored. In this study, mixing Rb+ ions in precursor solution is reported to significantly promote the crystallinity of phenylethylammonium (PEA+) based RP perovskites without impacting on the major orientation of perovskite grains, which leads to increased power conversion efficiencies from 12.5% to 14.6%. It is found that the added Rb+ ions prefer to accumulate at crystal growing front and form Rb+ ions‐rich region, which functions as mild crystal growth inhibitor to retard the absorption and diffusion of organic cations at growing front and hence regulates crystal growing rate. The retarded crystal growth benefits PEA‐based RP perovskite films with elevated crystal qualities and prolonged carrier recombination lifetimes. Similar increased crystallinity and photovoltaic performance are achieved in other RP perovskites with non‐linear organic cations such as phenylmethylammonium (PMA+), 1‐(2‐naphthyl)‐methanammoniun (NMA+) by adding Rb+ ions, demonstrating using a small amount of growth inhibitor as a general route to regulate crystal growth.

SARS-CoV-2 Mpro inhibitors: identification of anti-SARS-CoV-2 Mpro compounds from FDA approved drugs

Recent outbreak of COVID-19 pandemic caused by severe acute respiratory syndrome-Coronavirus-2 (SARS-CoV-2) has raised serious global concern for public health. The viral main 3-chymotrypsin-like cysteine protease (Mpro), known to control coronavirus replication and essential for viral life cycle, has been established as an essential drug discovery target for SARS-CoV-2. Herein, we employed computationally screening of Druglib database containing FDA approved drugs against active pocket of SARS-CoV-2 Mpro using MTiopen screen web server, yields a total of 1051 FDA approved drugs with docking energy >−7 kcal/mol. The top 10 screened potential compounds against SARS-CoV-2 Mpro were then studied by re-docking, binding affinity, intermolecular interaction, and complex stability via 100 ns all atoms molecular dynamics (MD) simulation followed by post-simulation analysis, including end point binding free energy, essential dynamics, and residual correlation analysis against native crystal structure ligand N3 inhibitor. Based on comparative molecular simulation and interaction profiling of the screened drugs with SARS-CoV-2 Mpro revealed R428 (−10.5 kcal/mol), Teniposide (−9.8 kcal/mol), VS-5584 (−9.4 kcal/mol), and Setileuton (−8.5 kcal/mol) with stronger stability and affinity than other drugs and N3 inhibitor; and hence, these drugs are advocated for further validation using in vitro enzyme inhibition and in vivo studies against SARS-CoV-2 infection. Communicated by Ramaswamy H. Sarma

Effects of SNF472, a Novel Inhibitor of Hydroxyapatite Crystallization in Patients Receiving Hemodialysis — Subgroup Analyses of the CALIPSO Trial

IntroductionCoronary artery calcium (CAC) is highly prevalent and linked with poor outcomes in patients receiving maintenance hemodialysis, and its reduction may improve patient prognosis. SNF472, a selective inhibitor of hydroxyapatite crystallization, slows CAC progression in patients receiving maintenance hemodialysis. In this analysis, we assessed the efficacy of SNF472 in prespecified patient subgroups.MethodsIn a randomized clinical trial SNF472 300 mg, SNF472 600 mg, or placebo were infused thrice weekly in 91, 92, and 91 patients receiving maintenance hemodialysis and with CAC at baseline, respectively. In prespecified subanalyses, the percent change in CAC volume score (CACvs) from baseline to week 52 in modified intention-to-treat (mITT) and per-protocol (PP) populations was calculated in the following subgroups: age, sex, diabetes mellitus, dialysis vintage, prior atherosclerotic cardiovascular disease, baseline use of non-calcium and calcium-based phosphate binders, calcimimetics, activated vitamin D, warfarin, and statins.ResultsIn the main trial, SNF472 significantly reduced CACvs progression compared with placebo (11% versus 20% mITT analyses; P = 0.016; 8% vs. 24% PP analyses; P < 0.001). Treatment differences for CACvs progression were similar across all subgroups, and all interaction P values were non-significant in mITT and PP analyses.ConclusionsSNF472 treatment for 52 weeks reduced CACvs progression compared with placebo in a broad range of patients receiving maintenance hemodialysis. Future studies will determine the impact of SNF472 on cardiovascular events in this population.

Production, structure-function relationships, mechanisms, and applications of antifreeze peptides.

Growth of ice crystals can cause serious problems, such as frozen products deterioration, road damage, energy losses, and safety risks of human beings. Antifreeze peptides (AFPs), a healthy and effective cryoprotectant, have great potential as ice crystal growth inhibitors for a variety of frozen products. In this review, methods and technologies for the production, purification, evaluation, and characterization of AFPs are comprehensively summarized. First, this review describes the preparation of AFPs, including the methods of enzymatic hydrolysis, chemical synthesis, and microbial fermentation. Next, this review introduces the major methods by which to evaluate AFPs' antifreeze activity, including nanoliter osmometer, differential scanning calorimetry, splat-cooling, the biovaluation model, and novel technology. Moreover, this review presents an overview of the molecular characteristics, structure-function relationships, and action mechanisms of AFPs. Furthermore, advances in the application of AFPs to frozen food, including frozen dough, meat products, fruits, vegetable products, and dairy, are summarized andholistically analyzed. Finally, challenges of AFPs and future perspectives on their use are also discussed. An understanding of the production, structure-function relationships, mechanisms and applications of AFPs provides inspiration for further research into the use of AFPs in food science and food nutrition applications.