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PloS One 2024The purpose of this work was to investigate the degree of agreement between two distinct approaches for measuring a set of blood values and to compare comfort levels...
The purpose of this work was to investigate the degree of agreement between two distinct approaches for measuring a set of blood values and to compare comfort levels reported by participants when utilizing these two disparate measurement methods. Radial arterial blood was collected for the comparator analysis using the Abbott i-STAT® POCT device. In contrast, the non-invasive proprietary DBC methodology is used to calculate sodium, potassium, chloride, ionized calcium, total carbon dioxide, pH, bicarbonate, and oxygen saturation using four input parameters (temperature, hemoglobin, pO2, and pCO2). Agreement between the measurement for a set of blood values obtained using i-STAT and DBC methodology was compared using intraclass correlation coefficients, Passing and Bablok regression analyses, and Bland Altman plots. A p-value of <0.05 was considered statistically significant. A total of 37 participants were included in this study. The mean age of the participants was 42.4 ± 13 years, most were male (65%), predominantly Caucasian/White (75%), and of Hispanic ethnicity (40%). The Intraclass Correlation Coefficients (ICC) analyses indicated agreement levels ranging from poor to moderate between i-STAT and the DBC's algorithm for Hb, pCO2, HCO3, TCO2, and Na, and weak agreement for pO2, HSO2, pH, K, Ca, and Cl. The Passing and Bablok regression analyses demonstrated that values for Hb, pO2, pCO2, TCO2, Cl, and Na obtained from the i-STAT did not differ significantly from that of the DBC's algorithm suggesting good agreement. The values for Hb, K, and Na measured by the DBC algorithm were slightly higher than those obtained by the i-STAT, indicating some systematic differences between these two methods on Bland Altman Plots. The non-invasive DBC methodology was found to be reliable and robust for most of the measured blood values compared to invasive POCT i-STAT device in healthy participants. These findings need further validation in larger samples and among individuals afflicted with various medical conditions.
Topics: Humans; Male; Female; Adult; Point-of-Care Systems; Middle Aged; Blood Gas Analysis; Oxygen; Bicarbonates; Hydrogen-Ion Concentration; Hemoglobins; Algorithms; Carbon Dioxide
PubMed: 38889168
DOI: 10.1371/journal.pone.0304706 -
Analytical Chemistry Jul 2024G-quadruplex (G4) DNA is considered as a prospective therapeutic target due to its potential biological significance. To understand G4 biological roles and function, a...
G-quadruplex (G4) DNA is considered as a prospective therapeutic target due to its potential biological significance. To understand G4 biological roles and function, a G4-specific fluorescent probe is necessary. However, it is difficult for versatile G4 to precisely recognize without perturbing their folding dynamics. Herein, we reported that flavone P0 can be a fluorescent probe for G4 DNA-specific recognition and have developed a highly selective detection of K ion by dimeric G4/P0 system. When comparing various nucleic acid structures, including G4, i-motif, ss/ds-DNA, and triplex, an apparent fluorescence enhancement is observed in the presence of G4 DNA for 85-fold, but only 8-fold for non-G4 DNA. Furthermore, based on fluorescent probe of flavone P0 for G4 DNA screening, the noncovalent dimeric G4/P0 system is exploited as a K sensor, that selectively responds to K with a 513-fold fluorescence enhancement and a detection range for K ion concentration from 0 to 500 mM. This K sensor also has a remarkably anti-interference ability for other metal cations, especially for a high concentration of Na. These results have demonstrated that flavone P0 is an efficient tool for monitoring G-quadruplex DNA and endows flavone P0 with bioanalytical and medicinal applications.
Topics: G-Quadruplexes; Flavones; Fluorescent Dyes; Potassium; DNA; Spectrometry, Fluorescence
PubMed: 38889097
DOI: 10.1021/acs.analchem.4c02368 -
Scientific Reports Jun 2024Iron in the leaching solution with high K and Na concentrations was usually precipitated as the typical hazardous and toxic jarosite residues. However, this method of...
Iron in the leaching solution with high K and Na concentrations was usually precipitated as the typical hazardous and toxic jarosite residues. However, this method of treatment has been greatly restricted by increasingly strict environmental regulations. Here we propose that iron can be precipitated from the solution with high K and Na concentrations as recyclable hematite products by adjusting the concentration ratio of sodium and potassium ions in the solution. The transformation behavior of jarosite into hematite in high concentration potassium ion and sodium ion solution was explained based on collision theory. The results indicated that in instances where the concentration ratio of Na/K is ≥ 4:1, the iron present in the solution can be effectively precipitated as a recyclable hematite product, as opposed to forming the conventional hazardous jarosite residue, even under conditions where the potassium ion concentration reaches levels as high as 4 g/L. On the other hand, thermodynamic and molecular dynamics simulations indicate that at a temperature of 185 °C, the decomposition transformation of Na-jarosite (32.64 kJ and 7.25 eV) is more energetically advantageous compared to that of K-jarosite (61.07 kJ and 15.31 eV). The results were verified by the leaching solution from smelting industry. The iron content in the residues is above 58%, the sulfur content is below 4%, the zinc content is below 1%, and the total iron concentration in the supernatant is about 4 g/L, reaching the production index of the smelting industry. The green, environmentally friendly, and recyclable separation of iron in a solution with high concentrations of potassium and sodium ions is achieved, which is of great significance for the treatment of iron-containing solution and wastewater in the chemical industry and metallurgy fields.
PubMed: 38886494
DOI: 10.1038/s41598-024-64502-w -
Nature Communications Jun 2024The renal epithelium is sensitive to changes in blood potassium (K). We identify the basolateral K channel, Kir4.2, as a mediator of the proximal tubule response to K...
The renal epithelium is sensitive to changes in blood potassium (K). We identify the basolateral K channel, Kir4.2, as a mediator of the proximal tubule response to K deficiency. Mice lacking Kir4.2 have a compensated baseline phenotype whereby they increase their distal transport burden to maintain homeostasis. Upon dietary K depletion, knockout animals decompensate as evidenced by increased urinary K excretion and development of a proximal renal tubular acidosis. Potassium wasting is not proximal in origin but is caused by higher ENaC activity and depends upon increased distal sodium delivery. Three-dimensional imaging reveals Kir4.2 knockouts fail to undergo proximal tubule expansion, while the distal convoluted tubule response is exaggerated. AKT signaling mediates the dietary K response, which is blunted in Kir4.2 knockouts. Lastly, we demonstrate in isolated tubules that AKT phosphorylation in response to low K depends upon mTORC2 activation by secondary changes in Cl transport. Data support a proximal role for cell Cl which, as it does along the distal nephron, responds to K changes to activate kinase signaling.
Topics: Animals; Proto-Oncogene Proteins c-akt; Potassium Channels, Inwardly Rectifying; TOR Serine-Threonine Kinases; Signal Transduction; Mice, Knockout; Potassium; Kidney Tubules, Proximal; Mice; Mechanistic Target of Rapamycin Complex 2; Phosphorylation; Male; Chlorides; Mice, Inbred C57BL
PubMed: 38886379
DOI: 10.1038/s41467-024-49562-w -
ENeuro Jun 2024Persistent activity in excitatory pyramidal cells is a putative mechanism for maintaining memory traces during working memory. We recently demonstrated persistent...
Persistent activity in excitatory pyramidal cells is a putative mechanism for maintaining memory traces during working memory. We recently demonstrated persistent interruption of firing in fast-spiking parvalbumin-expressing interneurons (PV-INs), a phenomenon which could serve as a substrate for persistent activity in pyramidal cells through disinhibition lasting hundreds of milliseconds. Here, we find that hippocampal CA1 PV-INs exhibit type 2 excitability, like striatal and neocortical PV-INs. Modelling and mathematical analysis showed that the slowly inactivating potassium current K1 contributes to type 2 excitability, enables the multiple firing regimes observed experimentally in PV-INs, and provides a mechanism for robust persistent interruption of firing. Using a fast/slow separation of times scales approach with the K1 inactivation variable as a bifurcation parameter shows that the initial inhibitory stimulus stops repetitive firing by moving the membrane potential trajectory onto a co-existing stable fixed point corresponding to a non-spiking quiescent state. As K1 inactivation decays, the trajectory follows the branch of stable fixed points until it crosses a subcritical Hopf bifurcation then spirals out into repetitive firing. In a model describing entorhinal cortical PV-INs without K1, interruption of firing could be achieved by taking advantage of the bistability inherent in type 2 excitability based on a subcritical Hopf bifurcation, but the interruption was not robust to noise. Persistent interruption of firing is therefore broadly applicable to PV-INs in different brain regions but is only made robust to noise in the presence of a slow variable, K1 inactivation. Persistent activity in neuronal networks is thought to provide a substrate for multiple forms of memory. The architecture of neuronal networks across many brain regions involves a small number of locally-projecting inhibitory neurons that control many excitatory pyramidal neurons which provide the output of the region. We propose that persistent silencing of fast-spiking parvalbumin-expressing inhibitory interneurons (PV-INs) can result in persistent activity of pyramidal neurons. We use a mathematical approach and computer simulations to show how a slowly changing state of a particular ion channel controls the long-lasting silence imposed by persistent interruption. Overall, our results provide a conceptual framework that positions the persistent interruption of PV-INs firing as a potential mechanism for persistent activity in pyramidal cells.
PubMed: 38886063
DOI: 10.1523/ENEURO.0190-24.2024 -
Journal of Environmental Radioactivity Jun 2024Metal hexacyanoferrates (MHCF) are a class of inorganic adsorbents used for wastewater management due to the presence of interstitial sites for capturing heavy metal...
Metal hexacyanoferrates (MHCF) are a class of inorganic adsorbents used for wastewater management due to the presence of interstitial sites for capturing heavy metal ions. In present work, we are reporting the synthesis of magnetic nanocomposite of FeO/graphene oxide/potassium copper hexacyanoferrate via wet chemical and coprecipitation approach. Potassium copper hexacyanoferrate (KCuHCF) and Graphene oxide (GO) both are marvelous adsorbents but their nano-size becomes a major obstacle in their separation process after the adsorption of the radionuclides. Thus, our synthesized nanocomposite FeO/GO/KCuHCF enhances the recovery of KCuHCF even after radioactive Cs adsorption with adsorption capacity of 18 mg g coinciding well with the Langmuir adsorption isotherm mechanism. The synthesized adsorbent is characterized thoroughly using UV-Visible spectroscopy, FT-IR, TGA, XPS, Raman spectroscopy, TEM-EDAX and XRD. This synthesized nanocomposite is used for the batch extraction of radioactive Cs from low level radioactive waste (LLW). The extraction kinetics followed pseudo-second-order kinetics mechanism.
PubMed: 38885562
DOI: 10.1016/j.jenvrad.2024.107481 -
ACS Applied Materials & Interfaces Jul 2024Electrode/electrolyte interfacial ion transfer is a fundamental process occurring during insertion-type redox reactions at battery electrodes. The rate at which ions...
Electrode/electrolyte interfacial ion transfer is a fundamental process occurring during insertion-type redox reactions at battery electrodes. The rate at which ions move into and out of the electrode, as well as at interphase structures, directly impacts the power performance of the battery. However, measuring and quantifying these ion transfer phenomena can be difficult, especially at high electrolyte concentrations as found in batteries. Herein, we report a scanning electrochemical microscope method using a common ferri/ferrocyanide (FeCN) redox mediator dissolved in an aqueous electrolyte to track changes in alkali ions at high electrolyte concentrations (up to 3 mol dm). Using voltammetry at a platinum microelectrode, we observed a reversible shift of ∼60 mV per decade change in K concentrations. The response showed high stability in sequential measurements and similar behavior in other aqueous electrolytes. From there, we used the same FeCN mediator to position the microelectrode at the surface of a potassium-insertion electrode. We demonstrate tracking of local changes in the K concentration during insertion and deinsertion processes. Using a 2D axisymmetric, finite element model, we further estimate the effective insertion rates. These developments enable characterization of a key parameter for improving batteries, the interfacial ion transfer kinetics, and future work may show mediators appropriate for molar concentrations in nonaqueous electrolytes and beyond.
PubMed: 38885040
DOI: 10.1021/acsami.4c03645 -
Analytical Sciences : the International... Jun 2024It has been suggested that the chelating agent 2-(2-(1-thiophene-2-yl) ethylidene) hydrazinyl) benzoic acid (TEHBA) be utilized to extract, separate and measure...
Rapid spectrophotometric determination and extraction of platinum(IV) from pharmaceuticals assisted by 2-(2-(1-(thiophene-2-yl) ethylidene) hydrazinyl) benzoic acid (TEHBA).
It has been suggested that the chelating agent 2-(2-(1-thiophene-2-yl) ethylidene) hydrazinyl) benzoic acid (TEHBA) be utilized to extract, separate and measure platinum(IV) by UV-visible spectrophotometry at the microgram level. Following 5 min of heating the reaction mixture in a water bath, Pt(IV)-TEHBA complex formed. This complex was formed in the presence of potassium iodide solution with a molar absorption coefficient 1.9 × 10 dm mol cm. At 420 nm, the substance exhibited the greatest absorption. As Beer's law described, the Pt(IV)-TEHBA complex for platinum(IV) has a beer's range of 10-50 μg cm. It was determined that the proportion ratio of the Pt(IV)-TEHBA complex was 1:1 after its extraction. Despite the investigation of interference from various ions, it was ascertained that the method exhibited selectivity exclusively towards platinum(IV). The trace amounts of platinum(IV) were extracted and quantified from synthetic mixtures representing alloys, binaries and ternary synthetic mixtures. The process of extracting platinum(IV) from pharmaceutical samples involves the implementation of a specific method. Moreover, the procedure exhibits a progressive segregation of palladium(II), platinum(IV) and nickel(II) while also boasting its ease of operation.
PubMed: 38884903
DOI: 10.1007/s44211-024-00612-9 -
ACS Omega Jun 2024Transition-metal dichalcogenides (TMDs) and their alloys are vital for the development of sustainable and economical energy storage alternatives due to their large...
Transition-metal dichalcogenides (TMDs) and their alloys are vital for the development of sustainable and economical energy storage alternatives due to their large interlayer spacing and hosting ability for alkali-metal ions. Although the Li-ion chemically correlates with the Na-ion and K-ion, research on batteries with TMD anodes for K is still in its infancy. This research explores TMDs such as molybdenum disulfide (MoS) and tungsten disulfide (WS) and TMD alloys such as molybdenum tungsten disulfide (MoWS) for both sodium-ion batteries (NIBs) and potassium-ion batteries (KIBs). The cyclic stability test analysis indicates that in the initial cycle, the MoS NIB demonstrates exceptional performance, with a peak charge capacity of 1056 mAh g, while retaining high Coulombic efficiency. However, the WS KIB underperforms, with the least charge capacity of 130 mAh g in the first cycle and exceptionally low retention at a current density of 100 mA g. The MoWS TMD alloy exhibits a moderate charge capacity and cyclic efficiency for both NIBs and KIBs. This comparison study shows that decreasing sizes of alkali-metal ions and constituent elements in TMDs or TMD alloys leads to decreased resistance and slower degradation processes as indicated by cyclic voltammetry and electrochemical impedance spectroscopy after 10 cycles. Furthermore, the study of probable electrochemical intercalation and removal processes of Na-ions and K-ions demonstrates that large geometrically shaped TMD flakes are more responsive to intercalation for Na-ions than K-ions. These performance comparisons of different TMD materials for NIBs and KIBs may promote the future development of these batteries.
PubMed: 38882118
DOI: 10.1021/acsomega.4c01966 -
Journal of Colloid and Interface Science Jun 2024Herein, a composite of N-doped carbon coated phosphating cobalt hollow nanofibers (N/C@CoP-HNFs) was synthesized by electrospinning, phosphating, and carbon coating...
Herein, a composite of N-doped carbon coated phosphating cobalt hollow nanofibers (N/C@CoP-HNFs) was synthesized by electrospinning, phosphating, and carbon coating processes. When employed as multifunctional electrode materials for potassium-ion batteries (PIBs) and lithium-sulfur (Li-S) batteries, the N/C@CoP-HNFs demonstrated notable electrochemical properties. Specifically, it delivered an initial specific capacity of 420.4 mA h g at a current density of 100 mA g, with a sustained capacity of 190.8 mA h g after 200 cycles in PIBs, and a specific capacity of 1448 mA h g at a current density of 0.5C in Li-S batteries, which is considered relatively high for these types of battery technology. This good performance may due to the combination of the carbon nitrogen layer and cobalt phosphide bilayer hollow tube structure, which is conducive to telescoping the diffusion length of ions and electrons and buffer volume variation, and effectively inhibits the shuttle effect. Density functional theory (DFT) calculations were also used to explore the energy storage mechanism of the material. The possible adsorption sites and corresponding adsorption energy of K were analyzed, and the advantages of the material were explored by calculating the diffusion barrier and state density. The theoretical simulations further validated the strong adsorption capability of CoP for polysulfides. This work is expected to provide new ideas for new energy storage materials.
PubMed: 38879992
DOI: 10.1016/j.jcis.2024.06.097