Synthesis and Characterization of Nano-Hydroxyapatite Obtained from Eggshell via the Hydrothermal Process and the Precipitation Method.

Hydroxyapatite (HA) is a major component of the inorganic minerals in the hard tissues of humans and has been widely used as a biomedical ceramic material in orthopedic and dentistry applications. Because human bone contains several impurities, including carbonates, chlorides, fluorides, magnesium, and strontium, human bone minerals differ from stoichiometric HA. Additionally, natural bone is composed of nano-sized HA, and the nanoscale particles exhibit a high level of biological activity. In this paper, HA is prepared via the hydrothermal process because its reaction conditions are easy to control and it has been shown to be quite feasible for large-scale production. Therefore, the hydrothermal process is an effective and convenient method for the preparation of HA. Furthermore, eggshell is adopted as a source of calcium, and mulberry leaf extract is selectively added to synthesize HA. The eggshell accounts for 11% of the total weight of a whole egg, and it consists of calcium carbonate, calcium phosphate, magnesium carbonate, and organic matter. Eggshell contains a variety of trace elements, such as magnesium and strontium, making the composition of the synthesized HA similar to that of the human skeleton. These trace elements exert considerable benefits for bone growth. Moreover, the use of eggshell as a raw material can permit the recycling of biowaste and a reduction in process costs. The purpose of this study is to prepare HA powder via the hydrothermal method and to explore the effects of hydrothermal conditions on the structure and properties of the synthesized HA. The room-temperature precipitation method is used for the control group. Furthermore, the results of an immersion test in simulated body fluid confirm that the as-prepared HA exhibits good apatite-forming bioactivity, which is an essential requirement for artificial materials to bond to living bones in the living body and promote bone regeneration. In particular, it is confirmed that the HA synthesized with the addition of the mulberry leaf extract exhibits good in vitro biocompatibility. The morphology, crystallite size, and composition of the carbonated nano-HA obtained herein are similar to those of natural bones. The carbonated nano-HA appears to be an excellent material for bioresorbable bone substitutes or drug delivery. Therefore, the nano-HA powder prepared in this study has great potential in biomedical applications.

Uranium Speciation in a Chalky Soil.

In this article, the speciation and behavior of anthropogenic metallic uranium deposited on natural soil are approached by combining EXAFS (extended X-ray absorption fine structure) and TRLFS (time-resolved laser-induced fluorescence spectroscopy). First, uranium (uranyl) speciation was determined along the vertical profile of the soil and bedrock by linear combination fitting of the EXAFS spectra. It shows that uranium migration is strongly limited by the sorption reaction onto soil and rock constituents, mainly mineral carbonates and organic matter. Second, uranium sorption isotherms were established for calcite, chalk, and chalky soil materials along with EXAFS and TRLFS analysis. The presence of at least two adsorption complexes of uranyl onto carbonate materials (calcite) could be inferred from TRLFS. The first uranyl tricarbonate complex has a liebigite-type structure and is dominant for low loads on the carbonate surface (<10 mgU/kg(rock)). The second uranyl complex is incorporated into the calcite for intermediate (∼10 to 100 mgU/kg(rock)) to high (high: >100 mgU/kg(rock)) loads. Finally, the presence of a uranium-humic substance complex in subsurface soil materials was underlined in the EXAFS analysis by the occurrence of both monodentate and bidentate carboxylate (or/and carbonate) functions and confirmed by sorption isotherms in the presence of humic acid. This observation is of particular interest since humic substances may be mobilized from soil, potentially enhancing uranium migration under colloidal form.

Accelerated carbonate biomineralisation of Venetia diamond mine coarse residue deposit (CRD) material - A field trial study.

Field trials combining mined kimberlite material (Coarse Residue Deposit; CRD) and mine derived microbes show accelerated kimberlite weathering at surface conditions - a potential method for accelerated carbon sequestration via mineral bio­carbonation. A photosynthetic biofilm suspension (20L), sourced from the Venetia diamond mine (Limpopo, South Africa) pit wall, was cultured in 3 × 1000 L bioreactors using BG-11 medium. Bioreactors supplemented with Fine Residue Deposit (FRD) kimberlite material enhanced microbial growth and kimberlite weathering. This (ca. 1.44 kg) wet weight bio-amendment corresponded to ca. 1.5 × 109Acidithiobacillus spp. sized bacteria/g CRD (20 kg FRD growth supplement +60 kg FRD used for harvesting biomass +850 kg CRD used in the field trial experiment). This bio-amendment promoted carbonate precipitation and subsequent cementation under surface conditions (0-20 cm). Microbial inoculation accelerated pedogenesis of CRD materials. A soil-like substrate resulted from weathering under environmental conditions in Johannesburg from January 2020 to April 2021. Over this 15-month experiment, the biodiversity found in the inoculum shifted due to the selective pressure of the kimberlite. The natural, endogenous biosphere, when combined with the inoculum, accelerated carbonate precipitation in the upper 20 cm of the bioreactor by between +1 wt% and + 2 wt%. Conversely, carbonation of the bioreactor at depth (20-40 cm) decreased by ca. 1 wt%. All the secondary carbonate observed in the bioreactors was biogenic in nature, i.e., possessing microbial fossils. This secondary carbonate took the form of both radiating acicular crystals as well as colloform intergranular cements. This microbial inoculum and resulting geochemical changes promoted the transformation of kimberlite into a Technosol, capable of supporting the germination and growth of self-seeding, windblown grasses, which enhanced weathering in the rhizosphere. The maximum secondary carbonate production is consistent with a ca. 20 % mine site CO2e offset.

Analytical Investigation of Iron-Based Stains on Carbonate Stones: Rust Formation, Diffusion Mechanisms, and Speciation.

In cultural heritage, unaesthetic stains on carbonate stones due to their close contacts with metals are of concern for the preservation of sculptures, monumental facades and archeological finds of various origin and antiquities. Rust stains made up of various oxidized iron compounds are the most frequent forms of alteration. The presence of ferric iron on rust-stained marble surfaces was confirmed in previous studies and oriented the choice of the best cleaning method (based on complexing agents specific for ferric ions). However, the composition of rust stains may vary along their extension. As the corrosion of the metallic iron proceeds, if the oxygen levels in the surroundings are low and there are no conditions to favor the oxidation, ferrous ions can also diffuse within the carbonate structure and form a variety of intermediate compounds. In this study, the iron stains on archeological marbles were compared with those artificially produced on Carrara marbles and Travertine samples. The use of integrated techniques (optical and scanning electron microscopy as well as Mössbauer and XPS spectroscopy) with complementary analytical depths, has provided the overall information. Rust formation and diffusion mechanisms in carbonates were revealed together with the evolution of iron speciation and identification of phases such as ferrihydrite, goethite, maghemite, nanomagnetite, and hematite.

Multi-scale approach to assess total porosity and pore size in four different kinds of carbonate rocks.

Petroleum is, at present, still the main energy source in the world. Most of it is stored in carbonate rock reservoirs with complex inner structures and pores ranging from nanometers to dozens of meters. Knowing the rock's entire pore network is indispensable to perform an effective petroleum extraction. X-ray microtomography, a technique that generates images from samples' inner structure and a powerful tool to evaluate the 3D pore network, was employed in this scientific research to scan four kinds of carbonate rocks (Dolomite, Desert Pink, Indiana, and Winterset) in five different pore scales (90 µm, 13 µm, 5.5 µm, 1.0 µm, and 65 nm). A multi-scale approach based on the number of pores was applied to integrate different pore scale data and assess the total porosity as well as each sample pore size distribution. The results were compared to classical Mercury Injection Capillary Pressure (MICP) results, demonstrating a fair agreement in total porosity in the two samples. Multi-scale porosity of the Dolomite sample was 17.7% against (18.9 ± 2.1)% of the MICP porosity. The Winterset sample had multi-scale porosity of 26.2%, while MICP porosity was (31.2 ± 0.6)%. Pore size distribution results were rather satisfactory, especially when overlapping regions in different scales were compared. In general, the multi-scale approach showed good potential. It still needs further evaluation to fine-tune some procedures and fluid flow simulation tests but might become a useful tool to study reservoir rocks with a wide range of pore sizes, such as carbonate rocks.

Leishmanicidal activities of biosynthesized BaCO3 (witherite) nanoparticles and their biocompatibility with macrophages.

The aim of this study was cost-effective and greener synthesis of barium carbonate (BaCO3 or witherite) nanoparticles with economic importance, and to evaluate their therapeutic potentials and biocompatibility with immune cells. Barium carbonate nanoparticles were biosynthesized using black elderberry extract in one step with non-toxic precursors and simple laboratory conditions; their morphologies and specific structures were analyzed using field emission scanning electron microscopy with energy dispersive X-ray spectroscopy (FESEM-EDX). The therapeutic capabilities of these nanoparticles on the immune cells of murine macrophages J774 and promastigotes Leishmania tropica were evaluated. BaCO3 nanoparticles with IC50 = 46.6 µg/mL were more effective than negative control and glucantium (positive control) in reducing promastigotes (P < 0.01). Additionally, these nanoparticles with a high value of cytotoxicity concentration 50% (CC50) were less toxic to macrophage cells than glucantime; however, they were significantly different at high concentrations compared to the negative control.

Bio-based Poly(hydroxy urethane)s: Synthesis and Pre/Post-Functionalization.

New and emerging demand for polyurethane (PU) continues to rise over the years. The harmful isocyanate binding agents and their integrated PU products are at the height of environmental concerns, in particular PU (macro and micro) pollution and their degradation problems. Non-isocyanate poly(hydroxy urethane)s (NIPUs) are sustainable and green alternatives to conventional PUs. Since the introduction of NIPU in 1957, the market value of NIPU and its hybridized materials has increased exponentially in 2019 and is expected to continue to rise in the coming years. The secondary hydroxyl groups of these NIPU's urethane moiety have revolutionized them by allowing for adequate pre/post functionalization. This minireview highlights different strategies and advances in pre/post-functionalization used in biobased NIPU. We have performed a comprehensive evaluation of the development of new ideas in this field to achieve more efficient synthetic biobased hybridized NIPU processes through selective and kinetic understanding.

CdO/CdCO3 nanocomposite physical properties and cytotoxicity against selected breast cancer cell lines.

Cadmium Oxide nanoparticles have the lowest toxicity when compared to nanoparticles of other semiconductors and they are not detrimental to human and mammalian cells, thereby making them candidates for targeting cancer cells. Synadenium cupulare plant extracts were used to synthesize CdO/CdCO3 nanocomposite using cadmium nitrate tetrahydrate 98% as a precursor salt. The resultant nanoparticles were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy, ultraviolet visible spectroscopy, and Fourier transform infrared spectroscopy (FTIR). The nanoparticles were then screened for effect on breast cancer cell lines (MCF-7 and MDA MB-231) and Vero cell line to determine their growth inhibition effect. Cytotoxicity effect was evaluated using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. XRD showed the peaks of monteponite CdO and otavite CdCO3 nanoparticles. TEM results showed irregular and spherical particles of varying sizes, whilst SEM revealed a non-uniform morphology. FTIR results showed peaks of functional groups which are present in some of the phytochemical compounds found in S. cupulare, and point to the presence of CdO. Annealed CdO/CdCO3 NPs showed selectivity for MCF7 and MDA MB231 in comparison to Vero cell line, thereby supporting the hypothesis that cadmium oxide nanoparticles inhibit growth of cancerous cells more than non-cancerous cells.

An Atomic Force Microscopy Study on the Effect of ß-Galactosidase, α-L-Rhamnosidase and α-L-Arabinofuranosidase on the Structure of Pectin Extracted from Apple Fruit Using Sodium Carbonate.

The enzyme driven changes in plant cell wall structure during fruit ripening result in debranching, depolymerization and solubilization of pectin polysaccharides, which has an effect in terms of the postharvest quality losses in fruit. Atomic force microscopy (AFM) has revealed that diluted alkali soluble pectins (DASP) from fruit and vegetables have an interesting tendency to self-assemble into regular structures. However, the mechanism is not yet fully understood. The current study is aimed at investigating the role of neutral sugars, namely galactose, rhamnose and arabinose in the formation of the branched structure of DASP. ß-galactosidase, α-L-rhamnosidase and α-L-arabinofuranosidase enzymes were used for the treatment of DASP extracted from Golden Delicious apple flesh (Malus domestica cv. Golden Delicious). The effects of the selective degradation of pectic polysaccharides after 15, 30, 60, 90 and 120 min of incubation were observed using AFM. The α-L-rhamnosidase enzyme activity on pectin extracted with Na2CO3 did not cause any visible or measurable degradation of the molecular structure. The moderate effects of ß-galactosidase enzymatic treatment suggested the possible role of galactose in the branching of DASP molecules deposited on mica. Data obtained for α-L-arabinofuranosidase indicated the crucial role of arabinose in the formation and preservation of the highly branched structure of the DASP fraction.

La-based-adsorbents for efficient biological phosphorus treatment of wastewater: Synergistically strengthen of chemical and biological removal.

The present work demonstrated the invention of synergistically strengthen of chemical and biological removal of phosphorus (P) in biological wastewater treatment, which was achieved by exposure the bioreactors to different levels of La-based-adsorbents. We fabricated a high-performance La2O2CO3 micro-adsorbent (H-La2O2CO3) and added it into sequencing batch reactors. When activated sludge was exposed to 40 mg/L H-La2O2CO3 for 40 d, effluent total phosphorus (TP) concentration significantly decreased to approximately 0.18 mg/L, with the steady removal efficiency of 96.4%, which is superior to the biological phosphorus removal (BPR). The effect of H-La2O2CO3 dosages on P removal in biological wastewater treatment was also detailedly investigated. The H-La2O2CO3 adsorbent could not only capture P by chemical bonding itself, but also increased protein (PN) contents of extracellular polymeric substances (EPS) and changed the functional group of EPS to chemically adsorb P. Additionally, the results of 16s rDNA molecular analysis revealed that the species richness and microbial diversity varied with the different dosages of adsorbent. Sequence analyses showed that the appropriate concentration of H-La2O2CO3 addition increased the contents of several polyphosphate accumulating organisms (PAOs) at genus level in sludge.

Effect of chitosan coatings on the evolution of sodium carbonate-soluble pectin during sweet cherry softening under non-isothermal conditions.

The inhibiting effect of chitosan coating (2%) on the softening and sodium carbonate-soluble pectin (SSP) evolution of sweet cherries during non-isothermal storage was investigated. Chitosan coating significantly extend the softening (6.4% greater than the control group), maintained the SSP content (6.6% greater than the control group), and reduced the degradation of SSP by inhibiting the expression of the paPME1-5 genes, which regulating pectin methylesterase activity of sweet cherries under temperature variation. In addition, the results of methylation and monosaccharide composition indicated that the chitosan coating reduced demethylation of SSP and the loss of RG-I main and side chain neutral sugars. Atomic force microscopy images revealed that the coated sweet cherries contained more linked, branched, and long SSP chains and maintained the width of the pectin backbone (>140 nm). These results indicated that a chitosan coating is feasible to preserve postharvest fruit under non-isothermal conditions.

Removal of uranium(VI) from water using hydroxyapatite coated activated carbon powder nanocomposite.

Synthesis of hydroxyapatite coated activated carbon nanocomposite was carried out by in-situ chemical precipitation method. Different characterizations confirm that, hydroxyapatite successfully coated over activated carbon powder. Extensive sorption studies of U(VI) on the nanocomposite were conducted to know the effect of contact time, humic acid, carbonate, ionic strength and pH. The study revealed that, the composite material is a more efficient sorbent for U(VI) compared to precursors, which removes U(VI) ion without altering physicochemical properties of water. Sorption exhibits multilayer adsorption on heterogeneous surface and follows chemisorptions. Practical applicability of the material was demonsteted by spiking tap water with U(VI) ion at three different initial concentrations (50, 100 and 150 µg L-1) and the tap water was allowed to passed through a cartridge packed with composite. It was observed that, the concentration of U(VI) ion in eluted water reduced to 98.28%, 96.20% and 97.40%, respectively. This revealed that, the material possesses a huge potential for sequestrating dissolved U(VI) ion and can be used as alternate filtering material for dissolved U(VI) in complex natural water system.

Gold as a dopant in selenium-containing carbonated hydroxyapatite fillers of nanofibrous ε-polycaprolactone scaffolds for tissue engineering.

The necessity for finding a compromise between mechanical and biological properties of biomaterials spurs the investigation of the new methods to control and optimize scaffold processing for tissue engineering applications. A scaffold composed of ε-polycaprolactone fibers reinforced with carbonated hydroxyapatite (CHAP) dually doped with selenite oxyanions (Se) and cationic gold (Au) was synthesized using the electrospinning technique and studied at different contents of Au. Despite the fact that the amount of the Au dopant was relatively low, variations to it induced significant microstructural changes, affecting the cell response and mechanical properties in return. Au nanoparticles segregated as a separate, ternary phase at the highest Au content, corresponding to x = 0.8 in the AuxCa10-1.5x(PO4)5.8(SeO2)0.2-x(CO3)x(OH)2 stoichiometric formula of Au/Se-CHAP. Their appearance coincided with a rapid degeneration in the density and adhesion of osteoblastic cells grown on the scaffolds. In spite of this adverse effect, the cell spreading and proliferation improved with increasing the amount of the Au dopant in the Au/Se-CHAP particles of the scaffold in the x = 0.0-0.6 range, suggesting that the biological effects of Au in the ionic and in the nanoparticulate form on the implant integration process may be diametrically opposite. The addition of Au had a dramatic effect on some mechanical properties, such as toughness and strain at break, which were both reduced twice upon the introduction of Au into Se-CHAP at the lowest amount (x = 0.2) compared to the Au-free composite. The significant variation of physical and biological properties of these composite scaffolds with trace changes in the content of the Au dopant inside the ceramic filler particles is promising, as it provides a new, relatively subtle avenue for tailoring the properties of tissue engineering scaffolds for their intended biomedical applications.

Transport of uranium(VI) in red soil in South China: influence of initial pH and carbonate concentration.

Uranium-contaminated wastewater associated with uranium (U) mining and processing inevitably releases into soil environment. In order to assess the risk of U wastewater contamination to groundwater through percolation, U adsorption and transport behavior in a typical red soil in South China was investigated through batch adsorption and column experiments, and initial pH and carbonate concentration were considered of the high-sulfate background electrolyte solution. Results demonstrated that U adsorption isotherms followed the Freundlich model. The adsorption of U to red soil significantly decreased with the decrease of the initial pH from 7 to 3 in the absence of carbonate, protonation-deprotonation reactions controlled the adsorption capacity, and lnCs had a linear relationship with the equilibrium pH (pHeq). In the presence of carbonate, the adsorption was much greater than that in the absence of carbonate owing to the pHeq values buffered by carbonate, but the adsorption decreased with the increase of the carbonate concentration from 3.5 to 6.5 mM. Additionally, the breakthrough curves (BTCs) obtained by column experiments showed that large numbers of H+ and CO32- competed with the U species for adsorption sites, which resulted in BTC overshoot (C/C0 > 1). Numerical simulation results indicated that the BTCs at initial pH 4 and 5 could be well simulated by two-site chemical non-equilibrium model (CNEM), whereas the BTCs of varying initial carbonate concentrations were suitable for one-site CNEM. The fractions of equilibrium adsorption sites (f) seemed to correlate with the fractions of positively charged complexes of U species in solution. The values of partition coefficients (kd') were lower than those measured in batch adsorption experiments, but they had the same variation trend. The values of first-order rate coefficient (ω) for all BTCs were low, representing a relatively slow equilibrium between U in the liquid and solid phases. In conclusion, the mobility of U in the red soil increased with the decrease of the initial pH and with the increase of the initial carbonate concentrations.

Effect of mechanochemical activation of natural phosphorite structure as well as phosphorus solubility.

Mechanochemical treatment of phosphate rock is considered as an effective and ecologically clean way of treating the medium- and low-grade phosphorite which could be used as fertilizer instead of the high-grade phosphorite. In order to investigate the effects of different milling times on the mechanochemically activated phosphorite (lower total phosphorus content) by more efficient milling equipment with enhanced milling speed, phosphorus solubility in citric acid and structural characteristics of natural and mechanochemically activated phosphorite from Yichang, China were studied using scanning electron microscope, infrared spectroscopy and X-ray diffraction. Phosphorus solubility in citric acid increased proportionately with the milling time until 30 min (57.51%), but then gradually reached an equilibrium with the maximum (59.03%) in 50 min. These changes were mainly manifested in considerably reduced particle size, decreased crystallinity and increased structural defects of phosphorite due to substitution of PO43- with CO32- and the incorporation of OH-. With the incorporation of CO32- and OH-, the non-activated carbonate-fluorapatite (type B) was transformed into a mixture of carbonate-fluorapatite, hydroxyapatite, fluorocarbon hydroxyapatite and/or carbonate apatite, respectively during the process of mechanochemical activation. As a result of the structural and phase transformations after mechanochemical activation, phosphorus solubility remarkably increased.

Sustained delivery of olanzapine from sunflower oil-based polyol-urethane nanoparticles synthesised through a cyclic carbonate ring-opening reaction.

The forefront horizon of biomedical investigations in recent decades is parcelling-up and delivery of drugs to achieve controlled/targeted release. In this regard, developing green-based delivery systems for a spatiotemporal controlling therapeutic agent have drawn a lot of attention. A facile route based on cyclic carbonate ring-opening reaction has been utilised to synthesise a bio-based polyol-containing urethane bond [polyol-urethane (POU)] as a nanoparticulate drug delivery system of olanzapine in order to enhance its bioavailability. After characterisation, the nanoparticles were also estimated for in vitro release, toxicity, and pharmacokinetic studies. As olanzapine has shown poor bioavailability and permeability in the brain, the sustained release of olanzapine from the designed carriers could enhance pharmacokinetic effectiveness. POU in the aqueous solution formed micelles with a hydrophobic core and embedded olanzapine under the influence of its hydrophobic nature. Drug release from the nanoparticles (90 ± 0.43 nm in diameter) indicated a specific pattern with initial burst release, and then a sustained release behaviour (82 ± 3% after 168 h), by the Higuchi-based release mechanism. Pharmacokinetics assessments of POU-olanzapine nanoparticles were carried in male Wistar rats through intravenous administration. The obtained results paved a way to introduce the POU as an efficient platform to enhance the bioavailability of olanzapine in therapeutic methods.

Atmosphere-ocean oxygen and productivity dynamics during early animal radiations.

The proliferation of large, motile animals 540 to 520 Ma has been linked to both rising and declining O2 levels on Earth. To explore this conundrum, we reconstruct the global extent of seafloor oxygenation at approximately submillion-year resolution based on uranium isotope compositions of 187 marine carbonates samples from China, Siberia, and Morocco, and simulate O2 levels in the atmosphere and surface oceans using a mass balance model constrained by carbon, sulfur, and strontium isotopes in the same sedimentary successions. Our results point to a dynamically viable and highly variable state of atmosphere-ocean oxygenation with 2 massive expansions of seafloor anoxia in the aftermath of a prolonged interval of declining atmospheric pO2 levels. Although animals began diversifying beforehand, there were relatively few new appearances during these dramatic fluctuations in seafloor oxygenation. When O2 levels again rose, it occurred in concert with predicted high rates of photosynthetic production, both of which may have fueled more energy to predators and their armored prey in the evolving marine ecosystem.

The interaction between resveratrol and two forms of copper as carbonate and nanoparticles on antioxidant mechanisms and vascular function in Wistar rats.

BACKGROUND: Experimental studies have emphasized that cardiovascular alterations can be improved by the long-term use of resveratrol (trans-3,5,4'-trihydroxystilbene; RSV) as well as dietary copper (Cu) intake. METHODS: Male Wistar rats were supplemented for 8 weeks with Cu (6.5 mg/kg diet) as either nanoparticles (40 nm, CuNPs) or carbonate (CuCO3). Half of the studied animals were supplemented with RSV (500 mg/kg diet). Vascular function and blood plasma antioxidant status, expressed as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), lipid hydroperoxides (LOOH) and malondialdehyde (MDA) were analyzed. The activity of ceruloplasmin (Cp), lipid profile, fasting glucose, and concentrations of Cu and zinc (Zn) were analyzed. RESULTS: RSV supplementation resulted in the elevated activity of SOD and decreased CAT, GPx and LDL-cholesterol in both groups. RSV supplementation on CuNPs increased the participation of vasoconstrictor prostanoids and decreased ACh-induced vasodilation, while the participation of hyperpolarizing mechanism(s) was restored by activating KATP channels. Blood plasma glucose was decreased. RSV supplementation on CuCO3 enhanced ACh- and SNP-induced vasodilation and decreased NA-induced vasoconstriction. The lipid profile was improved, as well as Zn concentration. Meanwhile, Cu and Cp, and the markers of lipid peroxidation, reflected as LOOH and MDA, were decreased. CONCLUSION: The use of RSV during CuCO3 intake improves vascular responses, the lipid profile and the antioxidant mechanism(s). The beneficial role of RSV was not observed in the CuNP group and decreased ACh-induced vasodilation and increased participation of vasoconstrictor prostanoids in the vascular regulation were noticed.

Microspheres of alginate encapsulated minocycline-loaded nanocrystalline carbonated hydroxyapatite: therapeutic potential and effects on bone regeneration.

Background and objective: Tetracycline and its derivatives, combined with calcium phosphates, have been proposed as a delivery system to control inflammatory processes and chronic infections. The objective of this study was to evaluate the microspheres of alginate encapsulated minocycline-loaded nanocrystalline carbonated hydroxyapatite (CHAMINO) as a biomimetic device to carry out target-controlled drug delivery for alveolar bone repair. Methods: CHAMINO microspheres were implanted in a rat central incisor socket after 7 and 42 days. New bone was formed in both groups between 7 and 42 days of implantation. However, the bone growth was significantly higher for the CHAMINO microspheres. Results: The minocycline (MINO) loading capacity of the nanocrystaline carbonated hydroxyapatite (CHA) nanoparticles was 25.1±2.2 µg MINO/mg CHA for adsorption over 24 hrs. The alginate microspheres containing minocycline-loaded CHA were biologically active and inhibited the Enterococcus faecalis culture growth for up to seven days of the MINO release. An osteoblastic cell viability assay based on the resazurin reduction was conducted after the cells were exposed to the CHAMINO powder and CHAMINO microspheres. Thus, it was found that the alginate extracts encapsulated the minocycline-loaded CHA microspheres and did not affect the osteoblastic cell viability, while the minocycline-doped CHA powder reduced the cell viability by 90%. Conclusion: This study concluded that the alginate microspheres encapsulating the minocycline-loaded nanocrystalline carbonated hydroxyapatite exhibited combined antibacterial activity against Enterococcus faecalis with cytocompatibility and osteoconduction properties. The significant improvement in the new bone formation after 42 days of implantation suggests that the CHAMINO microsphere has potential in clinical applications of bone regeneration.

Development and deployment of integrated air pollution control, CO2 capture and product utilization via a high-gravity process: comprehensive performance evaluation.

In this study, a proposed integrated high-gravity technology for air pollution control, CO2 capture, and alkaline waste utilization was comprehensively evaluated from engineering, environmental, and economic perspectives. After high-gravity technology and coal fly ash (CFA) leaching processes were integrated, flue gas air emissions removal (e.g., sulfate dioxide (SO2), nitrogen oxides (NOx), total suspended particulates (TSP)) and CO2 capture were studied. The CFA, which contains calcium oxide and thus, had high alkalinity, was used as an absorbent in removing air pollution residues. To elucidate the availability of technology for pilot-scale high-gravity processes, the engineering performance, environmental impact, and economic cost were simultaneously investigated. The results indicated that the maximal CO2, SO2, NOx, and TSP removal efficiencies of 96.3 ±â€¯2.1%, 99.4 ±â€¯0.3%, 95.9 ±â€¯2.1%, and 83.4 ±â€¯2.6% were respectively achieved. Moreover, a 112 kWh/t-CO2 energy consumption for a high-gravity process was evaluated, with capture capacities of 510 kg CO2 and 0.468 kg NOx per day. In addition, the fresh, water-treated, acid-treated, and carbonated CFA was utilized as supplementary cementitious materials in the blended cement mortar. The workability, durability, and compressive strength of 5% carbonated CFA blended into cement mortar showed superior performance, i.e., 53 MPa ±2.5 MPa at 56 days. Furthermore, a higher engineering performance with a lower environmental impact and lower economic cost could potentially be evaluated to determine the best available operating condition of the high-gravity process for air pollution reduction, CO2 capture, and waste utilization.