[The influence of alternating magnetic field on in vitro litholysis of uroliths in blemaren water solutions].

THE AIM OF THE RESEARCH: increase of efficiency of urolith in vitro solution using water Blemaren medication solutions after their exposure to 2 Hz alternating magnetic field. MATERIALS AND METHODS: water solution of Blemaren medication with pH=6,15 in concentrations corresponding to single portion of medication (1 tablet m=3,5282 g per 250 ml of water) and uroliths (oxalates, urates including uncommon xanthine calculi). Composition of calculi was determined by means of X-ray tests and IR spectroscopy. Photometry of Blemaren with saluted portion of calculi was conducted. RESULTS: it was established that in the Blemaren solutions which had been previously exposed to 2 Hz alternating magnetic filed during one hour the solution process is 1.92 - 2 times more effective than in common water solutions. Discussion - in control solutions pH values increased 5.65 - 6.8 times in the course of time, whereas in the Blemaren solutions exposed to alternating magnetic field pH values remained virtually unaltered during the whole experiment. CONCLUSION: there were detected significant differences in pH values of Blemaren solutions and its solvent properties between solutions which were exposed to alternating magnetic filed and those which were not.

Formulation of novel low-sodium salts using potassium salts and dietary polysaccharide.

Potassium citrate (KC) and potassium lactate (KL) are considered as salt replacers due to their saltiness, processing advantages, and health benefits. However, the obvious bitter taste associated with these compounds has limited their use in salt substitutes. Despite this challenge, little attention has been paid to improving their sensory properties. This study provided evidence that dietary polysaccharide carrageenan can effectively mask the bitterness of KC and KL by specifically binding K+ and forming double helix chains. A highly accurate prediction model was then established for the saltiness and bitterness of low-sodium salts using mixture design principles. Three low-sodium salt formulas containing different potassium salts (KC, KL, KCl), NaCl, and carrageenan were created based on the prediction model. These formulas exhibited favorable saltiness potencies (>0.85) without any noticeable odor, preserving the sensory characteristics of high-sodium food products like seasoning powder while significantly reducing their sodium content. This research provides a promising approach for the food industry to formulate alternative low-sodium products with substantially reduced sodium content, potentially contributing to decreased salt intake.

Preventive effect of commercial desensitizing toothpastes on bovine enamel erosion in vitro.

This study evaluated in vitro commercial desensitizing toothpastes with respect to the prevention of erosion and explored the effect of their agents alone or in combination with fluoride. Bovine enamel blocks were randomly allocated to five groups of 20 and exposed to: Sensodyne ProNamel (1,425 ppm F as NaF, 5% KNO(3)), Sensodyne Original (no fluoride, 10% SrCl(2)), Colgate Sensitive (1,450 ppm F as sodium monofluorophosphate, 5% K citrate), Crest (fluoride-only toothpaste, 1,100 ppm F as NaF) and water (negative control). A second experiment was conducted with experimental dentifrices containing fluoride (NaF, 1,100 ppm F), 10% SrCl(2), 5% KNO(3 )or 5% K citrate alone or the latter three combined with F. The samples were submitted to four cycles, alternating demineralization (cola, 10 min) and remineralization (artificial saliva, 1 h). Before and between cyclic de- and remineralization, blocks were treated with slurries of the respective toothpastes or water (1 min). Erosive tissue loss was analyzed by profilometry. Data were analyzed by Kruskal-Wallis and Dunn's tests (p < 0.05). The mean erosion depth (+/- SE, mum) was significantly less for Colgate Sensitive (0.04 +/- 0.00), Sensodyne Original (0.06 +/- 0.01) and Crest (0.07 +/- 0.01) than for Sensodyne ProNamel (2.36 +/- 0.25) or water (2.92 +/- 0.24), which did not significantly differ from each other. Both F and the desensitizing agents alone reduced erosion, but no additive effect was found. In addition, the combination of F and KNO(3) did not reduce erosion. These in vitro results suggest that the presence of fluoride or desensitizing substances in toothpastes, alone or in combination, can reduce erosion of enamel, but this is not valid for all the formulations.

The Impact of Alternative Alkalinizing Agents on 24-Hour Urine Parameters.

OBJECTIVES: To determine if alternative alkalinizing agents lead to similar changes in 24-hour urine pH and citrate compared to potassium citrate (KCIT). Many stone formers cannot tolerate KCIT due to side effects or cost. In these patients, we have prescribed potassium bicarbonate or sodium bicarbonate as alternative alkali (AA), though their efficacy is unclear. METHODS: We performed a retrospective cohort study of adult stone formers seen from 2000 to 2018 with 24-hour urine analyses. Two analyses were performed. The first evaluated the alkalinizing and citraturic effects in patients with baseline low urine pH or hypocitraturia off of any alkalinizing medications, who were subsequently treated with either KCIT or AA. The second analysis compared the pH and citrate in patients changing from KCIT to an AA. Reasons for switching were abstracted by chart review and cost savings percentages were calculated using GoodRx medication prices. RESULTS: When starting alkali therapy, the median increase in pH from baseline was 0.64 for KCIT and 0.51 for AA (P = .077), and the median increase in citrate from baseline was 231 mg for KCIT and 171 mg for AA (P = .109). When switching alkali therapy, median pH and citrate did not significantly change. Hyperkalemia (24%), GI upset (19%), and cost (17%) were the most common reasons cited for switching to an AA. AA represented a savings of 86%-92% compared to KCIT. CONCLUSION: Alternative alkali appear to offer comparable improvements in 24-hour urine parameters and significant cost-savings compared to KCIT.

Isolation of caseins from whey proteins by microfiltration modifying the mineral balance in skim milk.

The objective of this work was to study the effect of different salts and salt concentration on the isolation of casein micelles from bovine raw skim milk by tangential flow microfiltration. Tangential flow microfiltration (0.22 microm) was conducted in a continuous process adding a modified buffer to maintain a constant initial sample volume. This buffer contained calcium chloride (CaCl2), sodium phosphate (Na2HPO4), or potassium citrate (K3C6H5O7) in concentrations ranging from 0 to 100 mM. The concentrations of caseins and whey proteins retained were determined by sodium dodecyl sulfate-PAGE and analyzed using the Scion Image software (Scion Corporation, Frederick, MD). A complete isolation of caseins from whey proteins was achieved using sodium phosphate in the range of 10 to 50 mM and 20 times the initial volume of buffer added. No whey proteins were detected at 50 mM but this was at the expense of low caseins being retained. When lower sodium phosphate concentrations were used, the amount of caseins retained was higher but a small amount of whey proteins were still detected by sodium dodecyl sulfate-PAGE. Among the salts tested, calcium chloride at 50 mM and all volumes of buffer showed the higher retention of casein proteins. The highest casein:whey protein ratio was found at 30 mM CaCl2, but no complete casein micelle isolation was achieved. Potassium citrate was the most ineffective salt because a rapid loss of caseins and whey proteins was observed at all concentrations and with low quantities of buffer added during the filtration process. Our results show the potential of altering the mineral balance in milk for isolation of casein micelles from whey proteins in a continuous tangential flow microfiltration system.

Effect of potassium citrate salts on the vapor-liquid equilibrium properties of aqueous solutions of alanine at different temperatures.

Water activity measurements by isopiestic method have been carried out on the aqueous solutions of alanine+potassium di-hydrogen citrate (KH(2)Cit) and alanine+tri-potassium citrate (K(3)Cit) over a range of temperatures at atmospheric pressure. From these measurements, values of the vapor pressure of solutions were determined. The effect of temperature and charge on the anion of salts on the vapor-liquid equilibrium of the investigated systems has been studied. The experimental water activities have been correlated successfully with the segment-based local composition Wilson and NRTL models. The agreement between the correlations and the experimental data is good.

A new method for plasma citrate determination by reversed-phase high-performance liquid chromatography after ultrafiltration extraction: an example for bioequivalence evaluation of a medicinal endogenous substance.

Bioequivalence studies of pharmaceutical preparations of medicinal endogenous substances are generally lacking, as the endogenous background is the main obstacle for both experimental design and drug analysis. We conducted a single-dose, self-control, 3-period crossover study to evaluate the bioequivalence of a sustained-release versus an immediate-release preparation of potassium citrate for the treatment of urinary tract stones. This study included a placebo period to monitor the dynamics of endogenous plasma citrate, which could therefore be subtracted during the data processing. Notably, a new convenient method for plasma citrate determination utilizing ultrafiltration extraction and direct reversed-phase high-performance liquid chromatography (HPLC) was successfully applied in the study after validation. To our knowledge, this is the first report using simple reversed-phase HPLC to analyze plasma citrate, and ultrafiltration also significantly simplified the plasma extraction procedure. HPLC was performed using an ODS column, with acetonitrile and 0.02 mol/l sulfuric acid (3:97 v/v) as the mobile phase and ultraviolet detection at 210 nm. Results showed linearity from 10 to 200 microg/ml, an extraction recovery of more than 90% and analysis variability within 15% for additive citrate. The concentration of dog endogenous plasma citrate was determined to be about 30-40 microg/ml. The sustained-release preparation was bioequivalent to the immediate-release preparation in terms of the extent of absorption, but it could not achieve full effects due to a tmax issue.

The role of ionic liquid [C4 C1 im]Br as an adjuvant on the two-phase formation and the extraction of l-phenylalanine in ABS composed of PEG400 and potassium citrate at different temperatures.

The potential of {polyethylene glycol 400 + potassium citrate} aqueous biphasic system (ABS) with ionic liquid (IL) 1-butyl-3-methylimidazolium bromide ([C4 C1 im]Br) as an adjuvant is examined for the extraction of l-phenylalanine (Phe), as a model biomolecule, at different temperatures and system compositions. The binodal curves and liquid-liquid equilibrium data were determined by the addition of 5 wt% IL to investigate its effect on phase diagrams and Phe partition coefficients. The results indicate that binodal curves of systems with and without IL are more deviated from each other with decreasing temperature. Moreover, IL has a high tendency to partition into the PEG-rich phase. This tendency increases with increasing temperature and system compositions. For Phe, the partition coefficients obtained in this work (KPhe ≈ 5.5-81.2) are significantly higher than those observed in other conventional PEG-inorganic salt ABS (KPhe ≈ 0.5-2.5), water-immiscible ILs two-phase extraction systems (KPhe ≈ 0.02-1.2), or even, in the IL-based ABS with the same IL as the main phase-forming component (KPhe ≈ 3.2). The phase hydrophobicity, salting-out and π⋯π stacking seem to be the main driving forces to affect the extraction aptitude of the studied ABS for Phe. Furthermore, the performance of using [C4 C1 im]Br as adjuvant to improve the partition of Phe in the studied ABS at different temperatures seems to be ruled by the differences in the phases hydrophobicities. Finally, the experimental tie lines and partition coefficients are accurately correlated using the NRTL model. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018 © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:1149-1166, 2018.

Photoimages and the release characteristics of lipophilic matrix tablets containing highly water-soluble potassium citrate with high drug loadings.

Two types of the carnauba wax-based lipophilic matrix tablet using spray-dried granules (SDT) or directly compressible powdered mixtures (DCT) were prepared for sustained release. The model drug was a highly water-soluble potassium citrate and loaded about 74% of the total tablet weight. The SDT slowly eroded and disintegrated during the release study without showing sustained release when the hydrophilic excipients were added. In contrast, the DCT was more efficient for sustained release. The release rate decreased with increasing carnauba wax concentration. In particular, the sustained release rate was markedly pronounced when the lipophilic stearyl alcohol and stearic acid were combined with the carnauba wax. The surface of the intact DCT appeared to be smooth and rusty. The DCT rose to the surface from the bottom of the vessel during the release test, and numerous pores and cracks with no signs of disintegration were also observed after the release test. The release profile was dependent on the formulation composition and preparation method of the matrix tablet. Diffusion-controlled leaching through the channels of the pores and cracks of the lipophilic matrix tablet (DCT) is a key to the sustained release.

Retrograde intrarenal surgery in the management of pediatric cystine stones.

OBJECTIVE: To investigate the efficacy and safety of retrograde intrarenal surgery (RIRS) in the treatment of pediatric cystine stones. STUDY DESIGN: Data of the pediatric patients who underwent RIRS for kidney stones were retrospectively evaluated. A total of 14 children with cystine stones managed with RIRS were identified. In addition to the patient demographics and stone characteristics, all retrospectively obtained operative data were evaluated and discussed in detail, with an emphasis on the success and complication rates. RESULTS: Mean age of the 14 cases was 10.9 ± 2.2 years (range: 7-15). Mean stone size was 13.6 ± 2.4 mm (range: 10-18) (Summary table). Of these stones, four were located in the renal pelvis, three were in the lower, three were in the middle and the remaining four were located in upper calyx. Ureteral access sheath was used in 12 (85.7%) patients. The double-J ureteral stent was placed pre-operatively in one case and was inserted postoperatively in 12 cases. Mean operation time was 38.2 ± 7.2 min (range: 30-50). Complications were observed in two cases: mild ureteral laceration in the first and fever on the second postoperative day in the second patient. All of the patients were stone free on sonographic evaluation at the 4-week follow-up evaluation. Although potassium citrate treatment was initiated in 11 patients, tiopronin treatment was initiated in four patients for recurrence prophylaxis during long-term follow-up. During a mean follow-up period of 25.7 ± 5.2 months, stone recurrence was noted in one patient. DISCUSSION: Treatment of patients with cystine stones is challenging, due to high risk of rapid recurrence in the presence of residual fragments. Besides allowing complete stone clearance in all cases in the current series, RIRS is a highly reproducible method that can be safely performed, even in recurrences. The major limitations of the current study were low number of patients and short follow-up period. CONCLUSION: The results clearly indicated that RIRS is a safe treatment modality in the management of pediatric cystine stones.

Facile preparation of intercrossed-stacked porous carbon originated from potassium citrate and their highly effective adsorption performance for chloramphenicol.

Recently, antibiotics pollution has attracted more interests from many researches which causes potential risks on the ecosystem and human health. Herein, the porous carbons (PCs) was prepared by directly simultaneous carbonization/self-activation of potassium citrate at 750-900°C for chloramphenicol (CAP) removal from aqueous solution. The batch experiments were studied, which indicated that PCs prepared at 850°C, namely PCPCs-850, possessed excellent adsorption ability for CAP with a maximum adsorption amount of 506.1mgg-1. Additionally, PCPCs-850 showed a large BET surface area of 2337.06m2g-1 and microporosity of 89.11% by N2 adsorption-desorption experiment. The Langmuir and pseudo-second-order model could more precisely describe the experimental data. And thermodynamic analysis illustrated that CAP adsorption onto PCPCs-850 was an endothermic and spontaneous process. Importantly, the adsorbent exhibited good stability and regeneration after four times cycles. Based on these excellent performance, it is potential that PCPCs-850 can be used as a promising adsorbent for treating contaminants in wastewater.

Variable temperature EPR studies of Cu²+ and VO²+ doped potassium dihydrogen citrate (C6H7KO7).

Electron paramagnetic resonance (EPR) studies of single crystals and powder samples of Cu(2+) and VO(2+) doped potassium dihydrogen citrate (PDHC) have been carried out at different temperatures. The temperature-dependant g and A values have been obtained for powder spectra of both Cu(2+) and VO(2+) ions in PDHC and the ground state of Cu(2+) ion has been determined. The powder spectra recorded for Cu(2+) ion in the temperature range 70-298 K are discussed with Jahn-Teller distortion. It is concluded that the g and A values of Cu(2+): PDHC show the static property at low temperatures. For all temperatures, the result g(//)

Structure and substrate-induced conformational changes of the secondary citrate/sodium symporter CitS revealed by electron crystallography.

The secondary Na+/citrate symporter CitS of Klebsiella pneumoniae is the best-characterized member of the 2-hydroxycarboxylate transporter family. The recent projection structure gave insight into its overall structural organization. Here, we present the three-dimensional map of dimeric CitS obtained with electron crystallography. Each monomer has 13 a-helical transmembrane segments; six are organized in a distal helix cluster and seven in the central dimer interface domain. Based on structural analyses and comparison to VcINDY, we propose a molecular model for CitS, assign the helices, and demonstrate the internal structural symmetry. We also present projections of CitS in several conformational states induced by the presence and absence of sodium and citrate as substrates. Citrate binding induces a defined movement of a helices within the distal helical cluster. Based on this, we propose a substrate translocation site and conformational changes that are in agreement with the transport model of ''alternating access''.

Novel physico-biological treatment for the remediation of textile dyes-containing industrial effluents.

In this work, a novel remediation strategy consisting of a sequential biological and physical process is proposed to remove dyes from a textile polluted effluent. The decolorization ability of Anoxybacillus flavithermus in an aqueous effluent containing two representative textile finishing dyes (Reactive Black 5 and Acid Black 48, as di-azo and antraquinone class, respectively) was proved. The decolorization efficiency for a mixture of both dyes reached almost 60% in less than 12h, which points out the suitability of the selected microorganism. In a sequential stage, an aqueous biphasic system consisting of non-ionic surfactants and a potassium-based organic salt, acting as the salting out agent, was investigated. The phase segregation potential of the selected salts was evaluated in the light of different thermodynamic models, and remediation levels higher than 99% were reached.

EPR and optical studies of vanadium doped potassium dihydrogen citrate (C6H7KO7) single crystal.

An EPR and optical studies of VO2+ doped potassium dihydrogen citrate (PDHC) single crystals have been carried out at room temperature. It crystallizes in triclinic symmetry with the unit cell dimensions: a=11.343Å, b=13.078Å, c=6.272Å, α=89.79°, ß=94.36°, γ=104.2°. The angular variation of EPR spectra have shown that two different VO2+ complexes are located in different chemical environments and each environment contains one magnetically VO2+ site occupying substitutional position in the lattice and show very high angular dependence.

Partitioning of amino acids in the aqueous biphasic system containing the water-miscible ionic liquid 1-butyl-3-methylimidazolium bromide and the water-structuring salt potassium citrate.

In biotechnology, extraction by means of aqueous biphasic systems (ABS) is known as a promising tool for the recovery and purification of bio-molecules. Over the past decade, the increasing emphasis on cleaner and environmentally benign extraction procedures has led to enhanced interest in the ABS containing ionic liquids (ILs)-a new class of non-volatile alternative solvents. ABS composed of the hydrophilic IL {1-butyl-3-methylimidazolium bromide ([C4 mim]Br)} and potassium citrate-which is easily degraded-represents a clean media to green separation of bio-molecules. In this regard, here, the extraction capability of this ABS was evaluated through its application to the extraction of some amino acids. To gain an insight into the driving forces of amino acid partitioning in the studied IL-based ABS, the distribution of five model amino acids (L-tryptophan, L-phenylalanine, L-tyrosine, L-leucine, and L-valine) at different aqueous medium pH values and different phase compositions was investigated. The studies indicated that hydrophobic interactions were the main driving force, although electrostatic interactions and salting-out effects were also important for the transfer of the amino acids. Moreover, based on the statistical analysis of the driving forces of amino acid partitioning in the studied IL-based ABS, a model was established to describe the partition coefficient of three model amino acids, L-tryptophan, L-phenylalanine, and L-valine, and employed to predict the partition coefficient of two other model amino acids, L-tyrosine and L-leucine.

Effect of disaccharides on ion properties in milk-based systems.

The mean spherical approximation (MSA) theory is used to explain the impact of sugars on ion properties in milk-based systems by taking into account electrostatic interactions and volume exclusion effects. This study first focuses on the changes in Ca(2+) activity and pH in a solution consisting of CaCl(2), KCl, and K(3)citrate, as a function of sucrose concentration. MSA model calculations were compared with experimental results, and the model satisfactorily describes the ion properties. The excluded volume effects appear to account for a considerable increase in activity coefficient of the ions. This offers a sufficient explanation for the increase in Ca(2+) activity and the decrease in pH in milk-based systems with added disaccharides. In addition, hydration of milk proteins seems to enhance ion pair formation in milk. All disaccharides lead to similar modification of the thermodynamic properties of milklike systems, confirming that the observed effects are primarily due to volume exclusion effects.

Scalable recovery of plasmid DNA based on aqueous two-phase separation.

Future developments in gene therapy and DNA vaccination depend on cost-effective large-scale production of pharmaceutical-grade pDNA (plasmid DNA). Given the large amount of impurities present in the feedstock, purification processes that have high specificity and capacity at a moderate cost are required. In the present study, we describe a non-chromatographic procedure based on aqueous two-phase extraction allowing a fast and simply scalable capture step. PEG [poly(ethylene glycol)] in combination with potassium citrate or potassium phosphate was tested as phase component for extraction. By increasing either PEG or salt concentration, the partitioning of nucleic acids changed from bottom to top phase. Phase systems with a composition of 15% PEG 800 and 20% potassium phosphate at pH 7.0 showed a strong partitioning of pDNA to the bottom phase, linked to a clear decrease in open circular pDNA, while proteins, genomic DNA and RNA remain at the top or at the interphase. A great advantage of the current process is that the complete procedure of lysis, precipitation, clarification and extraction can be performed in a single vessel. The number of denatured and sheared genomic DNAs in a spiking experiment was found to be depleted by more than 99%.