Citrate Solution Research Articles

Advanced ion separation in polyamide nanofiltration membranes via interfacial polymerization regulated by dynamic polyphenol-metal coordination

Developing advanced nanofiltration membranes (NFMs) for inorganic salt ions separation remains a significant challenge in the value-added process of water treatment. Herein, we engineered a highly permeable-selective TA/Fe/Ca/PA-p NFM through a novel strategy for the interfacial polymerization (IP) regulated by the dynamic polyphenol-metal coordination. Interestingly, the dynamic coordination occurred after the substrate surface was first modified with tannic acid (TA) and Fe3+ and then coated with an aqueous phase solution containing piperazine (PIP) and Ca2+. In this process, the coordination competition between Fe3+ and Ca2+ for TA and the conversion of TA/Fe3+ bis-complex into tris-complex were conducive to forming more uniform TA/Fe/Ca complex on the substrate surface. Meanwhile, TA can also perform Michael addition with PIP to control the diffusion of PIP to the organic phase. Following the IP reaction, the nascent TA/Fe/Ca/PA NFM underwent post-treatment in a sodium citrate (SC) solution to dissociate the TA/Fe/Ca complex by further applying the dynamic coordination, resulting in a crumpled and thinner separation layer with desirable surface properties. The optimized TA/Fe2/Ca/PA-p NFM exhibited a pure water permeability of 36.1 L m−2 h−1⋅bar−1, nearly 2.4 times higher than that of the original PA NFM. Correspondingly, the Na2SO4 rejection reached 99.4 % and its Cl−/SO42− separation factor was 118.3. This outstanding permselectivity was mainly attributed to the decreased mass transfer resistance, the expanded effective permeability area, and the increased negative charge on the membrane surface. Additionally, the TA/Fe2/Ca/PA-p NFM was endowed with good operational stability, pressure resistance, and antifouling performance. This eco-friendly and cost-effective approach paves the way for fabricating high-performance NFMs and demonstrates the great potential of dynamic polyphenol-metal coordination in water treatment.

Fate of aflatoxin M1 from milk to typical Italian cheeses: Validation of an HPLC method based on aqueous buffer extraction and immune-affinity clean up with limited use of organic solvents

Aflatoxins are mycotoxins produced by several species of Aspergillus fungi which can be found in food and feed. When lactating animals are exposed to feedstuff contaminated by aflatoxin B1, they can excrete its hydroxylated form, aflatoxin M1 (AFM1), into milk. In EU, the AFM1 maximum limit in milk is 0.050 μg kg−1.In this work, we validated a method based on extraction of AFM1 from hard and soft cheese by a sodium citrate solution without the use of organic solvents, and analysis by HPLC-fluorescence detection after purification by immuno-affinity.The method proved to be fit-for-purpose and was successfully verified by participating to proficiency tests.Finally, starting from milk artificially contaminated with AFM1 we prepared four different types of Italian cheese to evaluate AFM1 transfer from milk to cheese and calculate concentration factors occurring during cheese-making processes. We observed an increase of AFM1 concentration in hard cheeses compared to soft cheeses.

Effect of the Thickness and Sb–O Content in Sb2S3 Thin Films to the Solar Cell Efficiency

Herein, Sb2S3 thin films are successfully prepared by hydrothermal method using the mixing solution of SbCl3 and sodium citrate as a novel Sb source. The influence of the growth temperature and time, growth solution volume on the properties of Sb2S3 thin films, and the photovoltaic performance of the corresponding solar cells is systematically investigated. The results reveal that the thickness and Sb–O content in Sb2S3 thin films decrease with the increase of the growth temperature and growth solution volume and decrease of the growth time. When the chemical composition and volume of the growth solution are 120 mM SbCl3, 276 mM sodium citrate, 180 mM Na2S2O3, 60 mM thioacetamide, and 28 mL, and the growth temperature and time are 150 °C and 2 h, the thickness and molar ratios of Sb–O:Sb–S/O in Sb2S3 thin films are 295 nm and 0.14 and the corresponding solar cells achieve the power conversion efficiency (PCE) of 7.36%, which is the highest PCE in Sb2S3 solar cells using hydrothermal method. Therefore, the effect of the growth temperature and time, specially the growth solution volume, on the thickness and Sb–O content in Sb2S3 thin films is important for improving the PCE of Sb2S3 solar cells.

Calcium-Citrate Anticoagulation during Continuous Renal Replacement Therapy in Patients with Metformin Intoxication: A Case Series, Mathematical Estimation of Citrate Accumulation, and Literature Review

Plain Language SummaryMetformin intoxication is a potentially life-threatening condition characterized by severe metabolic acidosis that could require intensive care unit admission and renal replacement therapy (RRT) for metformin removal. According to current guidelines, a citrate solution is commonly administered to generate regional anticoagulation in RRT due to its effect on chelating ionized calcium, an essential element of the coagulation pathway. Citrate metabolism can be impaired during metformin intoxication, and its administration could lead to accumulation worsening the metabolic acidosis. Citrate is not routinely measured, and its accumulation is clinically diagnosed by the ratio between total and ionized plasma calcium concentration (T/I calcium ratio) >2.5 or estimating the presence of unmeasured anions (UA), calculating the strong ion gap (SIG), i.e., the difference between the strong anions and cation, and the concentration of bicarbonate, dissociated albumin, and phosphates. We compared our results obtained from a case series of three patients with a theoretical model of citrate accumulation. Finally, we reviewed the literature to unveil clinical practice in this scenario. Our results support that diluted citrate can be safely used for RRT in patients with metformin toxicity, and the SIG is a valuable tool to estimate the presence of UA and can be used to detect and monitor citrate accumulation in this context.

Study on low methoxyl pectin (LMP) with varied molecular structures cross-linked with calcium inducing differences in the gel properties

The gel properties of pectin are significantly connected with its molecular structure. In this paper, we investigated the relationship between low methoxyl pectin (LMP) molecular structure and gel strength in the same degree of esterification (DE) range. LMP with DE of 31% ± 2% was prepared from citrus peels by acid, alkaline, enzymatic, and citric acid/sodium citrate solution methods. And based on data from monosaccharide composition, Mw, and NMR spectroscopy, the proportion of structural regions was speculated. The result revealed that C-LMP (pectin de-esterified by citric acid/sodium citrate solution method) was a highly branched macromolecular polysaccharide with short HG and enriched RG-I, with HG and RG-I proportions of 19.37% and 76.96%. According to the gel property investigation, of all the LMP samples, A-LMP-0.7 (pectin de-esterified by acid method at pH 0.7), which possessed lengthy HG and enriched RG-I domain, exhibited the best gel strength. C-LMP, A-LMP-0.5 (pectin de-esterified by acid method at pH 0.5), and B-LMP (pectin de-esterified by alkaline) failed to form a complete gel due to the low HG linearity, sparse RG-I and low Mw, respectively.

Transient, printable and recyclable gelatin hydrogels with enhanced mechanical sensing and electromagnetic shielding performance by incorporation of reduced graphene oxide

Transient and recyclable elastic materials have gained tremendous attention in the development of next-generation electronics. However, the fabrication of robust and printable electronic materials at mild conditions with biopolymer-based materials remains challenging. As a common and benign natural polymer, gelatin has easy availability, water solubility, good flexibility, and full biodegradability, yet its electromechanical performance is poor. Herein, a transient and recyclable gelatin hydrogel with remarkable mechanical resilience, conductivity and printability is constructed by a mild two-step reduction of the incorporated graphene oxide (GO) in ascorbic acid and sodium citrate solutions. The integration of reduced graphene oxide (rGO) in the gelatin hydrogel not only provides abundant multiple non-covalent interactions to dissipate the mechanical energy but also endows the hydrogel with desirable electrical conductivity, with the fracture stress and conductivity improved by 53 and 33 times, respectively. Under the synergistic merits, the hydrogel can be assembled as a compliant electromagnetic shielding layer with a shielding effectiveness of 29.4 dB, as well as resistive and capacitive sensors with high sensitivity (0.84 kPa−1), large gauge factor (8.2) and excellent stability (>20000 cycles under 60 kPa). As a proof-of-concept, the hydrogel was directly injected onto skin and assembled into a fully degradable self-powered sensing system for Morse code demonstration, and the hydrogel is permeable, photothermally healable, and washable. This work is a step towards the low-cost, ambient and scalable fabrication of green, reliable and versatile flexible electronics.

Mechanistic understanding of the effect of sodium citrate soaking of red kidney beans on their cooking behaviour

In this study, the role of soaking beans in a sodium citrate solution (a cation chelator) at pH = 4.4 and 41 °C in directing/improving the cooking behaviour of common beans was explored. The cooking behaviour of the pre-soaked red kidney beans was determined and the corresponding changes of phytate, minerals, starch, protein and pectin were quantified. Soaking beans in citrate buffer could accelerate softening of the beans during cooking in deionised water while subsequent cooking of beans in this buffer had a limited additional effect on softening compared to cooking in deionised water. Phytate hydrolysis during soaking in citrate buffer results in a release of Mg2+ and Ca2+. Both cations were leached into the soaking medium, higher amounts being observed for Mg2+ release to the soaking media because of the lower affinity of Mg2+ for pectin. It was observed that the pectin solubilisation rate in beans treated by sodium citrate buffer was positively correlated to bean softening. All of these results point out that soaking in a citrate buffer prohibits pectin Ca2+ cross linking therefore enhancing pectin solubilisation and thus increasing the bean softening rate constants during cooking, while starch and protein were not responsible for texture evolution.

Organization of histo-hematic barriers of the liver in Anglo-Nubian goat

The aim of this research was to establish features of the liver histo-hematic barriers ultrastructural organization of the Anglo-Nubian goat. The liver of an adult Anglo-Nubian goat was used as the material. The work was carried out using the electron microscopic method. Liver parenchymal tissue fragments were selected. These samples were fixed in a 2.0% glutaraldehyde solution on a cacodylate buffer for two hours. They were then washed in three portions of the same buffer and post-fixed in a 1.0% solution of osmium tetrachloride for one hour. The samples were then dehydrated in alcohols of ascending concentration and absolute acetone. The subsequent filling of the fragments was carried out in Epon-812. Ultrathin sections were obtained on an ultramicrotome, contrasted with a 2.0% aqueous solution of uranyl acetate and a solution of lead citrate. The ultrathin sections were photographed with a Jem-1011 electron microscope at magnifications of 2500-3000. Two histo-hematic barriers are detected in the liver of the studied animals hemato-hepatic and hepatobiliary. The hemato-hepatic barrier is formed by the plasmalemma of the apical end of the hepatocyte, covered by the glycocalyx, the perisinusoidal space of the Disse, the endotheliocyte of the sinusoid capillary, as well as Kupfer cells located in the lumen of the latter. The hepatobiliary includes all of the above structures, with the exception of Kupfer cells, as well as the plasmalemma of the basal end of the hepatocyte. All of the above structures in their organization have characteristic species features for Anglo-Nubian goats.

Green Approach for the Simultaneous Synthesis and Separation of Gold Nanoparticles.

Gold nanoparticles (AuNPs) have diagnostic and therapeutic applications as they are biocompatible and can be surface-functionalized. The use of organic solvents in the synthesis of AuNPs hampers their applications in the medicinal field. The large-scale production of nanoparticles requires their simultaneous synthesis and separation. Self-assembly of nanoparticles at the fluid-fluid interface facilitates their separation from the bulk and eliminates a downstream processing step. In this work, we exploit this in an aqueous two-phase system (ATPS) to synthesize and separate stable AuNPs. The ATPS was based on polyethylene glycol (PEG) and trisodium citrate dihydrate (citrate) as both these compounds can reduce Au ions. After the synthesis of nanoparticles, using one of the solutes, a complementary solution containing the other solute is added to form a two-phase system to facilitate self-assembly at the interface. The nanoparticles synthesized in different phases are characterized using UV-visible spectroscopy, scanning electron microscopy, and transmission electron microscopy. The AuNPs synthesized using the citrate solution are found to be unstable. Particles synthesized using the ATPS with PEG-600 are trapped at the interface while those using PEG-6000 remain in the bulk. Continuous synthesis and separation of nanoparticles in slug flow in a millichannel are demonstrated as a first step for large-scale controlled synthesis.

Investigation of Immunohistochemical Localization of Oxytocin Receptor in Diabetic and Non-Diabetic Mouse Heart

The aim of this study was to investigate the immunohistochemical localization of oxytocin receptor (OTR) in diabetic and non-diabetic mouse heart tissue. Eighteen male Balb-c adult (8-12 week) mice were used in the study. Animals were divided into three groups; control, sham and diabetes. The diabetes group was given STZ by intraperitoneally (i.p) injections and diabetes was induced. Sham group was again treated with sodium citrate solution by i.p. The animals in the control group did not receive any treatment. After 30 days of STZ application, mice were cervical dislocated under ether anesthesia and their heart tissues were removed. Each heart tissue was vertically divided into two parts and routine histological procedures were applied and then tissues were blocked in paraffin and sections were taken. For histological examination, Haematoxylin&Eosin (H&E), Crossman’s Triple staining and Periodic Acid Schiff (PAS) were applied to the sections. Immunoreactivity of OTR was determined by Avidin-Biotin-Peroxidase Complex (ABC) method. At the end of the study period; the body weight of the groups, blood glucose level, tissue weights and immunohistochemical localization of OTR in heart tissue samples and histological structure of tissue were compared. When weights of heart tissue were compared between the groups, there was no statistically significant difference between the groups (p>0.05). As a result of histological examinations, it was found that there was more degeneration in the cells in the myocardium of the heart in the diabetes group compared to the other groups. Immunohistochemical examinations showed that OTR showed similar immunoreactivity in sham and control groups. In the diabetic group, the immunoreactivity of OTR was similar in endothelial and capillary areas, but less in cell membrane, cytoplasm and purkinje cells. In conclusion, the results of this study showed that there is a significant relationship between the OTR, diabetes and heart tissue. As a result, it is thought that diabetes may have an effect on the cardiovascular system through the OTR (p

Enhanced popcorning using polyanionic chelating solutions as irrigation.

Poly-anionic compounds can chelate divalent cations and dissolve calcium oxalate stone. Our objective was to assess how much concurrent irrigation with poly-anionic chelating solutions during non-contact laser lithotripsy or popcorning could improve stone ablation rate. A popcorning model was created by lowering a ureteroscope with thulium fiber laser into a test tube calyx. Begostones of matching size and mass were placed in the test tube and treated with the laser while irrigating with different iso-osmolar poly-anionic solutions. We compared 0.9% sodium chloride (NaCl), sodium citrate, sodium hexa-metaphosphate, and sodium ethylenediaminetetraacetate (EDTA) solutions. After treatment, residual stones were passed through a 1mm sieve, and remaining fragments greater than 1mm were weighed as remaining stone mass. Average remaining stone mass after lithotripsy with NaCl irrigation was 27.8% (± 10.0%). The average remaining stone mass after lithotripsy with hexa-metaphosphate, sodium citrate, and EDTA irrigation was 28.9% (± 13.4%), 17.5% (± 10.5%), and 9.8% (± 5.7%) respectively. Compared with NaCl, there was a 37% reduction in remaining stone mass when using citrate (p = 0.008) and a 64.7% reduction when using EDTA irrigation during lithotripsy (p < 0.001). Concurrent irrigation with citrate or EDTA solutions synergistically enhances the efficacy laser lithotripsy in this in vitro popcorning model. This may lead to tangible improvements in endoscopic stone removal outcomes; however, the effectiveness on different stone types and safety during short duration lithotripsy should be further investigated.

Optical properties of Ag2S quantum dots

Colloidal solutions of silver sulfide quantum dots of various sizes were synthesized from low-concentration water solutions of silver nitrate, sodium sulfide and sodium citrate as stabilizer. The size of Ag2S quantum dots in colloidal solutions was determined by dynamic light scattering. The produced Ag2S quantum dots were dispersed in a polyvinyl alcohol (PVA) film matrix. The transmission and absorption spectra of PVA films containing Ag2S were measured in the wavelength interval 190–900 nm. A comparative study of the optical properties of PVA films with Ag2S quantum dots showed that a decrease of quantum dots to ∼ 6 nm leads to an increase in the band gap Eg of silver sulfide to ∼ 1.6 eV, which is almost twice larger than the band gap of bulk Ag2S. The optical properties of PVA films with Ag2S quantum dots smaller than 5 nm exhibit specific features associated with exciton transitions.

Formulation and quality assessment of acidheatcoagulated cheese

The formulation and standardization of acid-heat coagulated cheese was conducted to develop innovative and cost effective cheese product. The preliminary trails of acid-heat coagulated cheese were conducted to standardize optimum levels of salt, butter and sodium citrate solution. The sensory evaluation by a panel of trained and semi-trained members was conducted, and the C2: 1 Percent Salt Concentration, C6: 1.5 Per cent Butter Concentration and C9:1 Per cent Sodium Citrate Solution Concentration for mulations were selected for development of acid-heat coagulated cheese.The proximate analysis data of developed acid-heat coagulated cheese revealed that the moisture and total ash content were 45.9 and 2.5 percentage, respectively. The carbohydrates, proteins and fat and energy content values were reported as 11.6,15,25 percentage, respectively. The energy content was calculated to be 331.6 kcal. The developed cheese was packed in aluminium foil and stored at ambient (room temperature), refrigeration temperature (4°C) and deep freezer (-18°C). The storage studies of selected samples were conducted at 7 days interval to evaluates poilage of the acid-heat coagulated cheese. Thus, based on the results, it could be concluded that the acid-heat coagulated cheese developed is a type of unripened soft cheese and has agood nutritional composition to it.

Preparing and properties of films with Ag2S quantum dots in a polyvinyl alcohol matrix

Stable colloidal solutions of Ag2S quantum dots with a size of 2–3 to 28–30 nm were synthesized by a hydrochemical deposition in low-concentration water solutions of silver nitrate, sodium sulfide, and sodium citrate. A large absolute value of the measured zeta potential of colloidal solutions, a small change in the size of quantum dots and zeta potential during long-term storage of solutions for 1000 days after synthesis indicate their high temporal stability. The synthesized colloidal solutions were dispersed in a solution of polyvinyl alcohol. The resulting films of Ag2S quantum dots in a PVA matrix are flexible and have a thickness of no more than 0.03 mm. The use of the PVA matrix to prepare films with Ag2S quantum dots promotes the preservation and increase in the stability of colloidal particles due to their fixation in the polymer matrix. For the first time, the optical properties of Ag2S quantum dots of different sizes in PVA films were determined. Decreasing the size of Ag2S quantum dots to 2.6 nm leads to an increase in the band gap of silver sulfide to 1.85 eV. It is shown that repeated bending of the films has practically no effect on the Eg value of Ag2S quantum dots.

Ozone-loaded Pt(IV) prodrug self-assembled micelles with high bioavailability, low toxicity as a novel irradiation-controlled release treatment and the immune microenvironment editor for triple-negative breast cancer.

e12575 Background: A considerable part of TNBC shows poor response to the immune checkpoint blockades (ICBs) due to the immunosuppressive microenvironment. Chemotherapy performs well in synergizing with ICBs by improving tumor immunogenicity or eliminating the immunosuppressive tumor microenvironment. However, limited bioavailability, significant systematic toxicity and immunosuppressive metastatic niche induced by chemotherapy restrict its systematic application. Methods: We constructed the Pt(IV)-prodrug self-assembled micelles of O3_PFD@PtF with an ozone-loaded perfluorodecalin as the core (O3_PFD), and Pt(IV)-fluorocarbon chains assembled micelle as the shell (PtF). Results: The particle sizes of the prodrug were about 130.5 nm of PFD@PtF and 174.7 nm of O3_PFD@PtF, and both of the two showed good stability in the environment of different pH value and temperature. The Pt(IV) in the prodrug can be reduced and released in the sodium citrate solution. In addition, ozone was well stabilized by the PFD@PtF as the ROS donor and decomposed rapidly upon the irradiation excitation. O3_PFD@PtF boosted the level of GSH by promoting the intracellular redox balance with ROS and then the Pt(IV) was reduced to Pt(II) to release only within tumor. The prodrug was efficiently endocytosed into TNBC cells. Compared to cisplatin, a higher amount of Pt(II) was detected inserted into DNA in the O3_PFD@PtF combining irradiation treating group, which was released through depleting GSH donated by ROS. Accordingly, a remarkable reduction in IC50 was recorded in TNBC cells when O3_PFD@PtF was applied synergizing with irradiation. Furthermore, a relatively low IC50 was detected in non-ozone loaded prodrug-treated TNBC cells, which was attributed to the high concentration of background GSH, whereas the IC50 of PtF in Hacat was significantly higher than in other treating groups due to the low concentration of background GSH. Excellent inhibiting rates of the TNBC cells proliferation were observed in O3_PFD@PtF plus irradiation group 96 hours after treating, outperforming the conventional cisplatin plus irradiation group. We also observed a medium proliferation rate of TNBC cells in O3_PFD@PtF treating group in the absence of irradiation, which may be attributed to the Pt(II) released by the automatic decomposition of ozone. More importantly, cisplatin was reported to induced immunogenic cell death when synergizing with irradiation, but not alone. The dual potential to enhance TNBC proliferation inhibition and edit its immune microenvironment are now continuously detected. Conclusions: As a novel nano-prodrug with high efficiency and safty, O3_PFD@PtF plus irradiation is expected to improve the response of TNBC to ICBs by editing the tumor immune microenvironment.

Studies on the interference of citrate salts on the ion–solvent interactions of ionic liquid with water at different temperatures through volumetric, viscometric, and acoustic methods

The density, viscosity, and ultrasonic velocity of solutions of imidazolium-based ionic liquid, 1-ethyl-3-methyl imidazolium ethyl sulphate ([EMIm][EtSO4]) with aqueous solutions of sodium and potassium salts of citrate have been measured at five different temperatures i.e., T = (298.15–318.15) K and 0.1 MPa pressure. The experimentally found density (ρ) data have been utilized to compute the different volumetric properties such as apparent molar volume (Vϕ), partial molar volume (Vϕ0), partial molar expansivity (Eϕ0), Hepler’s constant (∂Eϕ0/∂T)p and volume transfer (ΔtrVϕ0). Similarly, the Jones-Dole equation, viscosity B-coefficient, transfer properties of B-Coefficient, (ΔtrB) and thermodynamics of viscous flow were calculated from viscosity consequences. The compression properties such as apparent molar isentropic compressibility (Kϕ,S), partial molar compressibility (Kϕ,S0) and transfer partial molar compressibility (ΔtrKϕ,S0) of IL have been deduced from the ultrasonic velocity. All the derived properties have been used to investigate the impact of citrate salts on the ion–solvent interactions of [EMIm][EtSO4] with water. The positive value of each of Hepler’s constants, and ΔtrKϕ,S0 and the negative sign of (dB/dT) indicates the existence of strong ion–solvent interactions and the cosmotrope nature of [EMIm][EtSO4] in the studied systems at the studied temperature ranges. The ion–solvent interactions of the present IL are found to be more in the solutions of potassium citrate (K3Cit) than sodium citrate (Na3Cit).

Cultivation of cells in alginate drops as a high-performance method of obtaining cell spheroids for bioprinting

Purpose of the study. Testing the protocol of obtaining cell spheroids of breast cancer cell cultures for bioprinting by growing in alginate drops.Materials and methods. Cells of breast cancer cell lines BT-20 and MDA-MB-453 were cultured in DMEM medium supplemented with 10 % FBS. Next, the cells were removed from the plastic using a trypsin-V ersene solution and resuspended in a sterile 2 % alginate solution in DPBS to the concentration of 105 cells/ml. Then the alginate solution with the cells was slowly dripped through a 30G needle into a sterile cooled solution of calcium chloride (100 mM) from a height of 10 cm. After polymerization, alginate drops were washed in DMEM and cultured for two weeks in DMEM with the addition of 10 % FBS at 37 °C and 5.0 % CO2.The spheroids formed in the alginate were photographed on the 3rd, 7th, 10th, and 14th days of cultivation, after which they were removed from the alginate by keeping in 55 mM sodium citrate solution with the addition of 20mM ethylenediaminetetraacetic acid (EDTA) and embedded in paraffin blocks according to the standard method, followed by histological examination.Results. Cellular spheroids were formed in both cell cultures already on the 3rd day of cultivation. From the 3rd to the 10th day in both cultures, a uniform growth of cell spheroids was observed with a gradual slowdown in the increase in the size of spheroids by the 14th day of cultivation. On the 10th day the proportion of cells that formed clones (more than 500 μm2 in size) was 25.2 % ± 7.1 % (n = 25) in the BT-20 culture and 38.5 % ± 9.9 % (n = 25) in MDA-MB-453 culture. On the 14th day, BT-20 culture was characterized by spheroids varying little in size and shape, with an average area of 1652 ± 175 µm2, having a dense structure with smooth edges. The spheroids in MDA-MB-453 culture turned out to be more loose and easily deformed, their size and shape varied noticeably, the average area of the spheroids was 2785 ± 345 µm2.Conclusion. The production of spheroids in alginate drops is inferior in speed to the methods of forming cell conglomerates in hanging drops or on microwells, but it surpasses these methods in productivity, which is comparable to the production of spheroids by constant medium stirring on low-adhesive substrates. In addition, the clonal nature of the obtained spheroids leads to an increase in research costs and thus limits their scalability.

Hydrothermal Synthesis of Silver Sulfide

Silver sulfide powders with submicro- and micrometer particle sizes have been synthesized by the hydrothermal method at temperatures from 373 to 453 K in aqueous and alcoholic solutions of silver nitrate, sodium sulfide and citrate, sulfur, and thiocarbamide. The crystal structures of the synthesized powders, morphology, composition, and particle size of silver sulfide have been analyzed by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray analysis, and gas adsorption. The powder particles have a similar morphology in the form of rectangular parallelepipeds and cubes with smoothed edges; the size of the powder particles depends on the synthesis conditions and ranges from ~500 to 2000 nm.

Utilization of Lead citrate on the peripheral Nervous Systemin Rat (An Experimental and Histological Study)

administrated of lead citrate solution with phosphate buffer saline orally in a dose of 250 mg/kg for thirty days. Animais were divided into four groups. Group A survived for 30 days. Group B for 60 days. Group C fbr 90 days and Groupb tzO days. Twenty animals were administrated phosphate buffer saline for 30 clays and classified into four 4 groups and survived for 30,60,90 and 120 days afterthe last dose. Atthe end of eachperiod the animals were scarified and segments of the peripheral nerve (Sciatic nerve) were removed and fixed in osmic acid 1o/o , then processed in graded glycerin 500/o , pure glycerin for obtaining teased nerve fibers . Specimens tbr miiror"opi" examination were done by application of the histological technique for obtaining transverse and longitudinal sections of the 6um thickness. The results of the present itr,iy d"*onstrated that the peripheral nerve fibers were affected after the 30,and 60 days mostly reflected by the presence of the wallerian degeneration ( destrr-rction of the myelin sheath ancl axon) of the most nerve fibers and at the period of 90 days after the last dose was indicated a regeneration of the most nerve fibers , but still there cerlain percentage of the degeneratecl nerve f-rbers and irregular outlines of its myelin sheath. After 120 days, Remyelination of most nerve fibers were detected associated with short internodes in between other intact nodes of Ranvier .

Simplified regional citrate anticoagulation protocol for CVVH, CVVHDF and SLED focused on the prevention of KRT-related hypophosphatemia while optimizing acid-base balance.

Hypophosphatemia is a common electrolyte disorder in critically ill patients undergoing prolonged kidney replacement therapy (KRT). We evaluated the efficacy and safety of a simplified regional citrate anticoagulation (RCA) protocol for continuous venovenous hemofiltration (CVVH), continuous venovenous hemodiafiltration (CVVHDF) and sustained low-efficiency dialysis filtration (SLED-f). We aimed at preventing KRT-related hypophosphatemia while optimizing acid-base equilibrium. KRT was performed by the Prismax system (Baxter) and polyacrylonitrile AN69 filters (ST 150, 1.5 m2, Baxter), combining a 18mmol/L pre-dilution citrate solution (Regiocit 18/0, Baxter) with a phosphate-containing solution (HPO42- 1.0mmol/L, HCO3- 22.0mmol/L; Biphozyl, Baxter). When needed, phosphate loss was replaced with sodium glycerophosphate pentahydrate (Glycophos™ 20mmol/20mL, Fresenius Kabi Norge AS, Halden, Norway). Serum citrate measurements were scheduled during each treatment. We analyzed data from three consecutive daily 8-h SLED-f sessions, as well as single 72-h CVVH or 72-h CVVHDF sessions. We used analysis of variance (ANOVA) for repeated measures to evaluate differences in variables means (i.e. serum phosphate, citrate). Because some patients received phosphate supplementation, we performed analysis of covariance (ANCOVA) for repeated measures modelling phosphate supplementation as a covariate. Forty-seven patients with acute kidney injury (AKI) or end stage kidney disease (ESKD) requiring KRT were included [11 CVVH, 11 CVVHDF and 25 SLED-f sessions; mean Acute Physiology and Chronic Health Evaluation II (APACHE II) score 25±7.0]. Interruptions for irreversible filter clotting were negligible. The overall incidence of hypophosphatemia (s-P levels <2.5mg/dL) was 6.6%, and s-P levels were kept in the normality range irrespective of baseline values and the KRT modality. The acid-base balance was preserved, with no episode of citrate accumulation. Our data obtained with a new simplified RCA protocol suggest that it is effective and safe for CVVH, CVVHDF and SLED, allowing to prevent KRT-related hypophosphatemia and maintain the acid-base balance without citrate accumulation. NCT03976440 (registered 6 June 2019).