Ca Ions Research Articles

Unveiling the protective role of anthocyanin in rice: insights into drought-induced oxidative stress and metabolic regulation.

This study investigates the impact of anthocyanin treatment on rice plants under drought stress, focusing on phenotypic, molecular, and biochemical responses. Anthocyanin were treated to one month old plants one week before the droughtexposure. Drought stress was imposed by using 10% polyethylene glycol (PEG 6000). Anthocyanin-treated plants exhibited significant enhancements in various traits, including growth parameters and reproductive characteristics, under normal conditions. When subjected to drought stress, these plants displayed resilience, maintaining or improving essential morphological and physiological features compared to non-treated counterparts. Notably, anthocyanin application mitigated drought-induced oxidative stress, as evidenced by reduced levels of reactive oxygen species (ROS) and lipid membrane peroxidation. The study also elucidates the regulatory role of anthocyanins in the expression of flavonoid biosynthetic genes, leading to increased levels of key secondary metabolites. Furthermore, anthocyanin treatment influenced the levels of stress-related signaling molecules, including melatonin, proline, abscisic acid (ABA), and salicylic acid (SA), contributing to enhanced stress tolerance. The enzymatic activity of antioxidants and the expression of drought-responsive genes were modulated by anthocyanins, emphasizing their role in antioxidant defense and stress response. Additionally, anthocyanin treatment positively influenced macronutrient concentrations, particularly calcium ion (Ca+), potassium ion (K+), and sodium ion (Na+), essential for cell wall and membrane stability. The findings collectively highlight the multifaceted protective effects of anthocyanins, positioning them as potential key players in conferring resilience to drought stress in rice plants. The study provides valuable insights into the molecular and physiological mechanisms underlying anthocyanin-mediated enhancement of drought stress tolerance, suggesting promising applications in agricultural practices for sustainable crop production.

Electrochemical performance of P4Se3 as high-capacity anode materials for monovalent and multivalent ion batteries

The increasing need for advanced anode materials with superior performance in rechargeable batteries has driven investigations into cutting-edge energy storage systems. This study delves into the potential of P4Se3 Molecular Cages (MCs) as innovative anode materials for both monovalent and multivalent ion batteries, including Na ion batteries (NIBs), Mg ion batteries (MIBs), Ca ion batteries (CIBs), Al ion batteries (AIBs), and Zn ion batteries (ZIBs) through a comprehensive Density Functional Theory (DFT) and molecular dynamics (MD) based investigations. The analyses encompass the electronic structure, structural stability, electrochemical performance, charge storage mechanisms, and redox properties to offer valuable insights into the potential of P4Se3 as an anode. The DFT calculations unveil critical aspects of adsorption, diffusion, and reaction kinetics in P4Se3 elucidating its potential as high-capacity and suitable anode material. The exothermic reactions between Na, Mg, Ca, Al, and Zn with host P4Se3 highlight its suitability for the intercalation process in monovalent and multivalent ion batteries. Furthermore, calculated storage capacities for NIB, MIB, CIB, AIB, and ZIB are found as 1484.84 mAhg−1, 519.69 mAhg−1, 1410.60 mAhg−1, 593.93 mAhg−1, and 74.24 mAhg−1 respectively. The voltage profiles indicate favorable open circuit voltages (OCV) of 0.31 V, 0.27 V, 0.55 V, and 3.3 V for NIB, MIB, CIB, and AIB respectively. The study employs climbing image nudged elastic band (Cl-NEB) simulations to compute diffusion barriers faced by monovalent and multivalent ions in the host structure. The calculated minimal diffusion barriers of 0.18 eV for NIB, 0.30 eV for MIB, 0.35 eV for CIB, 0.33 eV for AIB, and 0.71 eV for ZIB indicate fast charging capabilities due to efficient ion movement. Furthermore, the respective calculated values of diffusion coefficient are found as 5.27 × 10−10 m2/s, 5.27 × 10−9, 4.0 × 10−10 m2/s, 5.27 × 10−10 m2/s and 5.27 × 10−11 m2/s and respective values of ionic conductivity σ are found as 4.13 × 10−3 S/m, 14.57 × 10−2 S/m, 30.03 × 10−3 S/m, 16.65 × 10−3 S/m and 0.20 × 10−3 S/m for NIBs, MIBs, CIBs, AIBs and ZIBs. The findings of this study point out suitability of P4Se3 as anode material in monovalent and multivalent ion batteries.

Reactive Oxygen Species and Mitochondrial Calcium's Roles in the Development of Atherosclerosis.

In the last decade, there has been increasing evidence connecting mitochondrial dysfunction to the onset and advancement of atherosclerosis. Both reactive oxygen species (ROS) and the disruption of mitochondrial calcium (Ca2+) regulation have garnered significant attention due to their involvement in various stages of atherosclerosis. This abstract discusses the potential therapeutic applications of targeting mitochondrial calcium (Ca2+) and reactive oxygen species (ROS), while also providing an overview of their respective roles in atherosclerosis. The abstract underscores the importance of mitochondrial Ca2+ homeostasis in cellular physiology, including functions such as energy production, cell death signaling, and maintaining redox balance. Alterations in the mitochondria's Ca2+ handling disrupt all these procedures and speed up the development of atherosclerosis. Reactive oxygen species (ROS), generated during mitochondrial respiration, are widely recognized as significant contributors to the development of atherosclerosis. Through modulating the function of calcium ion (Ca2+) transport proteins, ROS can impact the regulation of mitochondrial Ca2+ handling. These oxidative modifications lead to vascular remodeling and plaque formation by impairing endothelial function, encouraging the recruitment of inflammatory cells, and promoting smooth muscle cell proliferation. Preclinical investigations indicate that interventions aimed at regulating the production and elimination of reactive oxygen species (ROS) hold promise for mitigating atherosclerosis. Targeting mitochondrial processes represents a prospective therapeutic strategy for addressing this condition. Further research is necessary to elucidate the intricate molecular mechanisms associated with mitochondrial dysfunction in atherosclerosis and develop effective therapeutic strategies to decelerate disease progression.

Moderation-excess interactions of epigallocatechin gallate and CaCl2 modulate the gelation performance of egg white transparent gels

In this study, the moderation–excess interaction of epigallocatechin gallate (EGCG) and calcium ions (Ca2+) to the gelation performance of transparent egg white protein (EWP) gel (EWG) was explored. The oxidation of EGCG introduced a yellowish-brown EWG, whereas the weakening of Ca2+ ionic bonds caused a notable reduction in the hardness of EWG, from 120.67 g to 73.57 g. Achieving the optimal EGCG-to-Ca2+ ratio in EWG conferred enhanced water-holding capacity to 86.98%, while an excess of EGCG attributed to the creation of a three-dimensional structure within the void “walls”. The elevated presence of EGCG influenced the ionic bonds and hydrophobic interactions, thereby presenting a moderate–excess relationship with sulfhydryl and disulfide bonds, β-sheet, and α-helical structures. Notably, EGCG reduced the digestibility of EWG to 50.06%, while concurrently fostering the creation of smaller particle sizes. This study provides a scientific basis for the controllable preparation and quality regulation of transparent EWG.

Selenium represses microRNA-202-5p/MICU1 aixs to attenuate mercuric chloride-induced kidney ferroptosis

Mercuric chloride (HgCl2) is a nephrotoxic contaminant that is widely present in the environment. Selenium (Se) can effectively antagonize the biological toxicity caused by heavy metals. Here, in vivo and in vitro models of Se antagonism to HgCl2-induced nephrotoxicity in chickens were established, with the aim of exploring the specific mechanism. Morphological observations and kidney function analysis showed that Se alleviated HgCl2-induced kidney tissue injury and cytotoxicity. The results showed that ferroptosis was the primary mechanism for the toxicity of HgCl2, as indicated by iron overload and lipid peroxidation. On the one hand, Se significantly prevented HgCl2-induced iron overload. On the other hand, Se alleviated the intracellular reactive oxygen species (ROS) levels caused by HgCl2. Subsequently, we focused on the sources of ROS during HgCl2-induced ferroptosis. Mechanically, Se reduced ROS overproduction induced by HgCl2 through mitochondrial calcium uniporter (MCU)/mitochondrial calcium uptake 1 (MICU1)-mediated mitochondrial calcium ion (Ca2+) overload. Furthermore, a dual luciferase reporter assay demonstrated that MICU1 was the direct target of miR-202-5p. Overall, Se represses microRNA-202-5p/MICU1 axis to attenuate HgCl2-induced kidney ferroptosis.

Evaluation of the Effect of Different Remineralizing Agents and Ozone Application on Artificial Carises

ABSTRACT This study aimed to assess the combined and individual effects of different remineralization agents and ozone application on initial caries. Seventy-two premolar teeth were collected. Three different toothpastes (Ipana, ROCS, and Gumgumix) were utilized. The samples were divided into eight groups (n = 8) for experimentation (Distilled water, Ipana+Ozone, Gumgumix+Ozone, ROCS+Ozone, Ipana, Gumgumix, ROCS, Ozone). Microhardness measurements were conducted initially. All samples were then immersed in a demineralization solution for 72 hours to induce initial caries. Then, microhardness measurements were repeated, and pH cycles were carried out for one-week. Finally, microhardness measurements and SEM-EDS analyses were performed. Ipana+Ozone exhibited the highest microhardness value, which was statistically significant compared to other groups except ROCS+Ozone (p < 0.05). Distilled water, Gumgumix+Ozone, and Gumgumix displayed the lowest microhardness values. Ozone application with remineralization agents led to higher precipitation of Ca ions. The demineralized group showed the lowest Ca, P, and F ions. While Ipana+Ozone and ROCS+Ozone had the highest Ca ions, Gumgumix+Ozone had the highest P ions. Within the study’s limitations, it can be concluded that ozone gas positively impacts the remineralization process in initial caries lesions. Additionally, mineral-containing products demonstrated a noteworthy capacity to reverse the demineralization process.

A Study on the Effect Mechanism of Pectin Modification on the Carrot Cell Wall’s Texture Formation under Ultrasonic and Infrared Drying

The carrot has a high water content, and dehydration is an important means to extend its edible period and reduce storage and transportation costs. In the case of infrared (IR) drying, the porosity of the product is low and the structure is compact; the textural properties of the product are improved by using combined ultrasound and infrared (US-IR) drying; however, there is a lack of reports on the mechanism of this. Pectin has an important influence on the formation of the textural properties of fruit and vegetable tissues. In order to investigate the mechanism of the change in endogenous pectin properties in the carrot cell wall under US-IR drying on the improvement of the textural properties of the product, different fractions of pectins (water-soluble pectin, chelating pectin, alkali-soluble pectin) of the carrot were extracted, separated, and analysed. The thermal stability, component and content changes, Fourier infrared (FTIR), X-ray diffraction (XRD), esterification degree, molecular weight, monosaccharide composition, Ca ion content, and atomic force microscopy (AFM) of the pectins were determined. The results showed that the changes in the contents and properties of the carrot pectins under US-IR conditions had a positive effect on the improvement of the textural properties of the carrot tissues.

Modelling spatio-temporal interactions between second messengers Ca and cAMP in a pancreatic -cell.

Calcium serves as a widespread second messenger in almost every human and animal cell. The regulation of various cellular processes, such as transcriptional control and the kinetics of membrane channels, is significantly influenced by intracellular calcium ions (Ca ), and linkages between Ca and other second messengers should activate signaling networks. The passage of ions across the cell membrane regulates Ca levels in pancreatic -cells and requires the coordinated interaction of various ion transport mechanisms and organelles. The signaling of Ca in -cells and its interactions with the intracellular dynamics of cyclic adenosine monophosphate (cAMP) is poorly understood. Therefore, the current investigation proposes a mathematical model to illustrate the spatiotemporal dynamical interaction between Ca and cAMP. In order to construct a one-dimensional mathematical model, the fundamental initial and boundary conditions derived from the physiological characteristics of the -cell are incorporated. The numerical results were obtained by MATLAB simulations using the finite element method and the Crank-Nicolson method. The current study aims to offer an update on regulation between Ca and cAMP signaling circuits, with a focus on interactions that occur in localized areas of the -cell. The model gives the individual effect of each parameter on the regulation of Ca and cAMP profiles in a -cell. Evidently, impairments in the regulation of messenger pathways contribute to the pathological conditions, as demonstrated by the results obtained.

Biological activity of tantalum oxide coating doped with calcium and strontium by micro-arc oxidation under osteoimmunomodulation

Tantalum is widely used in clinics due to its excellent properties. However, its high density and elastic modulus constrain its application as a large implant. The new porous tantalum material addresses the issue of incompatibility between the implant and the human body. Nevertheless, it still exhibits biological inertia and limited bone-bonding ability; therefore, it is necessary to modify its surface. At present, some surface modification methods have inconsistent results in vitro and in vivo. To solve this problem, this study described the preparation of a ceramic coating with a "trabeculae-like" structure on the surface of pure tantalum using micro-arc oxidation (MAO). Calcium and strontium ions were introduced by adding acetate to the electrolyte. The effects of incorporating bioactive ions Ca2+ and Sr2+ into the electrolyte on the coating's morphology, coating thickness, phase composition, roughness, hydrophilicity, and the activity of MC3T3-E1 osteoblast cells under osteoimmunomodulation were investigated. The results demonstrated that the introduction of bioactive ions did not change the porous morphology of the coating; instead, it led to an increase in coating thickness, enhancement of surface roughness and hydrophilicity, as well as promotion of osteoblast spreading, proliferation, and ALP activity. Moreover, it regulated the phenotypic polarization of RAW264.7 macrophages to augment osteoblast proliferation, spreading, and ALP activity, implying that the coating has superior osteogenic potential under osteoimmunomodulation.

Alkaliphilic and thermostable lipase production by leaf litter fungus Leptosphaerulina trifolii A SMR-2011.

Fungi that inhabit fire-prone forests have to be adapted to harsh conditions and fungi affiliated to Ascomycota recovered from foliar litter samples were used for bioprospecting of molecules such as enzymes. Agni's fungi isolated from leaf litter, whose spores are capable of tolerating 110 oC were screened for thermostable lipases. One of the isolates, Leptosphaerulina trifolii A SMR-2011exhibited high positive lipase activity than other isolates while screening through agar plate assay using Tween 20 in the medium. Maximum lipase activity (173.2 U/mg) of L. trifolii was observed at six days of inoculation and decreased thereafter. Among different oils used, the maximum lipase activity was attained by soybean oil (940.1 U/mg) followed by sunflower oil (917.1 U/mg), and then by mustard oil (884.8 U/mg), showing its specificity towards unsaturated fatty acids. Among the various organic nitrogen sources tested, soybean meal showed maximum lipase activity (985.4 U/mg). The partially purified enzyme was active over a wide range of pH from 8 to 12 with a pH optimum of 11.0 (728.1 U/mg) and a temperature range of 60-80 oC with an optimal temperature of 70 oC (779.1 U/mg). The results showed that lipase produced by L. trifolii is alkali stable and retained 85% of its activity at pH 11.0. This enzyme also showed high thermal stability retaining more than 50% of activity when incubated at 60 oC to 90°C for 2h. The ions Ca2+ and Mn2+ induced the lipase activity, while Cu2+ and Zn2+ ions lowered the activity compared to control. These results suggests that the leaf litter fungus L. trifolii serves as a potential source for the production of alkali-tolerant and thermostable lipase.

Recovery of Chromium and Two Solvents (Dichloromethane-DCM Tetrachloroethane-TCE) Using Nanofiltration and Reverse Osmosis Membranes from Leather Industry Wastewater

In this study, for removal of the leather industry pollutants and to recovery of chromium (Cr), dichloromethane (DCM) and tetrachloroethane (TCE) two sequential nanofiltration (NF) (NF90 and NF270) and two reverse osmosis (RO) (BW30 and SW30) reactor membranes were used. The membrane surface properties were investigated by Fourier Transform Infrared Spectroscopy-Attenuated Total Reflectance (FTIR-ATR) and Scanning Electron Microscopy (SEM). The permeate of the SW30 reverse osmosis exhibited high removals varying between 98% and 99% for sodium ion (Na+ ), potassium ion (K+ ), magnesium ions (Mg2+), calcium ions (Ca2+), total chemical oxygen demand (CODtotal), dissolved chemical oxygen demand (CODdis), dissolved organic carbon (DOC) and inert chemical oxygen demand (inert COD), Chromium (Cr3+ ), Dichloromethane and Tetrachloroethane. In the NF90 nanofiltration process lower removals were detected (96%-97%) for all pollutants mentioned above. The effluent of reverse osmosis with a BW30 membrane match to the Turkish Water Pollution Control Regulation rules for treated water discharged to the receiving environment while SW30 reverse osmosis membrane was perfect for ultimate treatment of the pollutants present in the leather industry discharges. From the concentrate of the SW30 reverse osmosis, 945 mg/l chromium, 460 mg/l dichloromethane and 360 mg/l tetrachloroethane were reused. The performance and recoveries of Cr and two solvents (DCM and TCE) data in NF and RO membrane reactors were evaluated with Artificial Neural Network (ANN) process and Kruskal Wallis test statistic coupled with Mann-Whitney U statistic in this study.

Square-planar Tetranuclear Cluster-based Alkaline Earth Metal-organic Frameworks with Enhanced Proton Conductivity.

Alkaline earth (AE) metal complexes have garnered significant interest in various functional fields due to their nontoxicity, low density, and low cost. However, there is a lack of systematic investigation into the structural characteristics and physical properties of AE-metal-organic frameworks (MOFs). In this research, we synthesized isostructural MOFs consisting of AE4(μ4-Cl) clusters bridged by benzo-(1,2;3,4;5,6)-tris(thiophene-2'-carboxylic acid) (BTTC3-) ligands. The resulting structure forms a truncated octahedral cage denoted as [AE4(m4-Cl)]6(BTTC)8, which further linked to a porous three-dimensional framework. Among the investigated AE ions (Ca, Sr, and Ba), the Ca4-MOF demonstrated good chemical stability in water compared to Sr4-MOF and Ba4-MOF. The N2 adsorption and solid-state UV-vis-NIR absorption behaviors were evaluated for all AE4-MOFs, showing similar trends among the different metal ions. Additionally, the proton conduction study revealed that the Ca4-MOF exhibited ultra-high proton conductivity, reaching 3.52×10-2 S cm-1 at 343 K and 98 % RH. Notably, the introduction of LiCl via guest exchange resulted in an improved proton conduction of up to 6.36×10-2 S cm-1 under similar conditions in the modified LiCl@Ca4-MOF. The findings shed light on the regulation of physical properties and proton conductivity of AE-MOFs, providing valuable insights for their potential applications in various fields.

Bioinspired core-shell nanofiber drug-delivery system modulates osteogenic and osteoclast activity for bone tissue regeneration

Osteogenic-osteoclast coupling processes play a crucial role in bone regeneration. Recently, strategies that focus on multi-functionalized implant surfaces to enhance the healing of bone defects through the synergistic regulation of osteogenesis and osteoclastogenesis is still a challenging task in the field of bone tissue engineering. The aim of this study was to create a dual-drug release-based core-shell nanofibers with the intent of achieving a time-controlled release to facilitate bone regeneration. We fabricated core-shell P/PCL nanofibers using coaxial electrospinning, where alendronate (ALN) was incorporated into the core layer and hydroxyapatite (HA) into shell. The surface of the nanofiber construct was further modified with mussel-derived polydopamine (PDA) to induce hydrophilicity and enhance cell interactions. Surface characterizations confirmed the successful synthesis of PDA@PHA/PCL-ALN nanofibers endowed with excellent mechanical strength (20.02 ± 0.13 MPa) and hydrophilicity (22.56°), as well as the sustained sequential release of ALN and Ca ions. In vitro experiments demonstrated that PDA-functionalized core-shell PHA/PCL-ALN scaffolds possessed excellent cytocompatibility, enhanced cell adhesion and proliferation, alkaline phosphatase activity and osteogenesis-related genes. In addition to osteogenesis, the engineered scaffolds also significantly reduced osteoclastogenesis, such as tartrate-resistant acid phosphatase activity and osteoclastogenesis-related gene expression. After 12-week of implantation, it was observed that PDA@PHA/PCL-ALN nanofiber scaffolds, in a rat cranial defect model, significantly promoted bone repair and regeneration. Microcomputed tomography, histological examination, and immunohistochemical analysis collectively demonstrated that the PDA-functionalized core-shell PHA/PCL-ALN scaffolds exhibited exceptional osteogenesis-inducing and osteoclastogenesis-inhibiting effects. Finally, it may be concluded from our results that the bio-inspired surface-functionalized multifunctional, biomimetic and controlled release core-shell nanofiber provides a promising strategy to facilitate bone healing.

Exploring the Effectiveness of Carboxymethylated and Crosslinked Albizia procera Gum in Diltiazem Hydrochloride Matrix Tablets: A Comparative Analysis.

This study investigates the efficacy of modified Albizia procera gum as a release-retardant polymer in Diltiazem hydrochloride (DIL) matrix tablets. Carboxymethylated Albizia procera gum (CAP) and ionically crosslinked carboxymethylated Albizia procera gum (Ca-CAP) were utilized, with Ca-CAP synthesized via crosslinking CAP with calcium ions (Ca2+) using calcium chloride (CaCl2). Fourier Transform (FT) IR analysis affirmed polymer compatibility, while differential scanning calorimetry (DSC) and X-ray diffraction (XRD) assessed thermal behavior and crystallinity, respectively. Zeta potential analysis explored surface charge and electrostatic interactions, while rheology examined flow and viscoelastic properties. Swelling and erosion kinetics provided insights into water penetration and stability. CAP's carboxymethyl groups (-CH2-COO-) heightened divalent cation reactivity, and crosslinking with CaCl2 produced Ca-CAP through -CH2-COO- and Ca2+ interactions. Structural similarities between the polymers were revealed by FTIR, with slight differences. DSC indicated modified thermal behavior in Ca-CAP, while Zeta potential analysis showcased negative charges, with Ca-CAP exhibiting lower negativity. XRD highlighted increased crystallinity in Ca-CAP due to calcium crosslinking. Minimal impact on RBC properties was observed with both polymers compared to the positive control as water for injection (WFI). Ca-CAP exhibited improved viscosity, strength, controlled swelling, and erosion, allowing prolonged drug release compared to CAP. Stability studies confirmed consistent six-month drug release, emphasizing Ca-CAP's potential as a stable, sustained drug delivery system over CAP. Robustness and accelerated stability tests supported these findings, underscoring the promise of Ca-CAP in controlled drug release applications.

Glucono-Delta-Lactone-Induced Alginate Gelation: New Insights into the Effect of the Cross-Linker Carrier Type on the Hydrogel Mechanics.

Physical alginate hydrogels commonly rely on "internal gelation" to introduce the cross-linker, e.g., calcium (Ca(II)) ions. These are released in a homogeneous manner by using a pH-sensitive Ca(II) carrier and glucono-delta-lactone (GDL) as the acidifier. Yet, it remains unclear how the carrier of the cross-linker affects the gelation process and final hydrogel properties. We therefore investigate two internal gelation methods using either Ca(II)-chelating ligand complexes or insoluble Ca(II)-based salts. Ionometry coupled with pH measurements reveals the release process of Ca(II) ions upon acidification, which is well described by simulations using the Hyperquad Simulation and Speciation program. We show that these findings correlate well with the evolution of the mechanical properties of the hydrogels. Although the two pH-triggered gelation methods appear to be similar, we demonstrate their differences in terms of the gelation kinetics and final cross-link density. The nature of the ligand or the salt significantly affects the fraction of the released Ca(II) ions and, hence, the mechanical properties of the final hydrogel for a given GDL concentration. Furthermore, for the first time, we demonstrate the competition between GDL and alginate in binding with Ca(II) ions. This study therefore provides different tools for the efficient formulation of alginate hydrogels.

Comparable properties of native K channels in the atrium and ventricle of snails

Mollusks, including snails, possess two chambered hearts. The heart and cardiomyocytes of snails have many similarities with those of mammals. Also, the biophysics and pharmacology of Ca, K, and Na ion channels resemble. Similar to mammals, in mollusks, the ventricular cardiomyocytes and K channels are often studied, which are selectively sensitive to antagonists such as 4-AP, E-4031, and TEA. Since the physiological properties of the ventricular cardiac cells of snails are well characterized, the enzymatically dissociated atrial cardiomyocytes of Cornu aspersum (Müller, 1774) were studied using the whole-cell patch-clamp technique for detailed comparisons with mice, Mus musculus. The incubation of tissues in a solution simultaneously containing two enzymes, collagenase and papain, enabled the isolation of single cells. Recordings in the atrial cardiomyocytes of snails revealed outward K+ currents closely resembling those of the ventricle. The latter was consistent, whether the voltage ramp or steps and long or short pulses were used. Interestingly, under identical conditions, the current waveforms of atrial cardiomyocytes in snails were similar to those of mice left ventricles, albeit the kinetics and the absence of inward rectifier K channel (IK1) activation. Therefore, the heart of mollusks could be used as a simple and accessible experimental model, particularly for pharmacology and toxicology studies.

Composite Aerogel Scaffolds Containing Flexible Silica Nanofiber and Tricalcium Phosphate Enable Skin Regeneration.

Poor hemostatic ability and less vascularization at the injury site could hinder wound healing as well as adversely affect the quality of life (QOL). An ideal wound dressing should exhibit certain characteristics: (a) good hemostatic ability, (b) rapid wound healing, and (c) skin appendage formation. This necessitates the advent of innovative dressings to facilitate skin regeneration. Therapeutic ions, such as silicon ions (Si4+) and calcium ions (Ca2+), have been shown to assist in wound repair. The Si4+ released from silica (SiO2) can upregulate the expression of proteins, including the vascular endothelial growth factor (VEGF) and alpha smooth muscle actin (α-SMA), which is conducive to vascularization; Ca2+ released from tricalcium phosphate (TCP) can promote the coagulation alongside upregulating the expression of cell migration and cell differentiation related proteins, thereby facilitating the wound repair. The overarching objective of this study was to exploit short SiO2 nanofibers along with the TCP to prepare TCPx@SSF aerogels and assess their wound healing ability. Short SiO2 nanofibers were prepared by electrospinning and blended with varying proportions of TCP to afford TCPx@SSF aerogel scaffolds. The TCPx@SSF aerogels exhibited good cytocompatibility in a subcutaneous implantation model and manifested a rapid hemostatic effect (hemostatic time 75 s) in a liver trauma model in the rabbit. These aerogel scaffolds also promoted skin regeneration and exhibited rapid wound closure, epithelial tissue regeneration, and collagen deposition. Taken together, TCPx@SSF aerogels may be valuable for wound healing.

Sildenafil Reverses the Neuropathological Alzheimer's Disease Phenotype in Cholinergic-Like Neurons Carrying the Presenilin 1 E280A Mutation.

Familial Alzheimer's disease (FAD) presenilin 1 E280A (PSEN 1 E280A) is characterized by functional impairment and the death of cholinergic neurons as a consequence of amyloid-β (Aβ) accumulation and abnormal phosphorylation of the tau protein. Currently, there are no available therapies that can cure FAD. Therefore, new therapies are urgently needed for treating this disease. To assess the effect of sildenafil (SIL) on cholinergic-like neurons (ChLNs) harboring the PSEN 1 E280A mutation. Wild-type (WT) and PSEN 1 E280A ChLNs were cultured in the presence of SIL (25μM) for 24 h. Afterward, proteinopathy, cell signaling, and apoptosis markers were evaluated via flow cytometry and fluorescence microscopy. We found that SIL was innocuous toward WT PSEN 1 ChLNs but reduced the accumulation of intracellular Aβ fragments by 87%, decreased the non-physiological phosphorylation of the protein tau at residue Ser202/Thr205 by 35%, reduced the phosphorylation of the proapoptotic transcription factor c-JUN at residue Ser63/Ser73 by 63%, decreased oxidized DJ-1 at Cys106-SO3 by 32%, and downregulated transcription factor TP53 (tumor protein p53), BH-3-only protein PUMA (p53 upregulated modulator of apoptosis), and cleaved caspase 3 (CC3) expression by 20%, 32%, and 22%, respectively, compared with untreated mutant ChLNs. Interestingly, SIL also ameliorated the dysregulation of acetylcholine-induced calcium ion (Ca2+) influx in PSEN 1 E280A ChLNs. Although SIL showed no antioxidant capacity in the oxygen radical absorbance capacity and ferric ion reducing antioxidant power assays, it might function as an anti-amyloid and antiapoptotic agent and functional neuronal enhancer in PSEN 1 E280A ChLNs. Therefore, the SIL has therapeutic potential for treating FAD.

Unlocking the potential of iron-containing mesoporous bioactive glasses: Orchestrating osteogenic differentiation in bone marrow mesenchymal stem cells and osteoblasts

Iron (Fe) is a crucial element in the human body, playing a significant role in bone metabolism. The release of Fe ions at bone defect sites can promote bone regeneration. In this study, we synthesized Fe-containing mesoporous bioactive glasses (Fe-MBGs) in SiO2-CaO-Fe2O3 composition using a sol-gel method. Regardless of the amount of incorporated Fe2O3 (up to 5 mol%), the Fe-MBGs maintained a mesoporous structure, and the inclusion of Fe2O3 did not alter their amorphous characteristics. However, the presence of Fe2O3 led to a reduction in both pore volume and specific surface area of Fe-MBGs. Notably, Fe-MBGs demonstrated degradability in physiological fluids and could sustain release of Si, Fe, and Ca ions. Higher concentrations of incorporated Fe2O3 were found to reduce the degradation of Fe-MBGs. All Fe-MBGs exhibited favorable bioactivity, as evidenced by the rapid formation of hydroxyapatite when exposed to simulated body fluid. Fe-MBGs also demonstrated concentration-dependent effects on BMSCs and Saos-2 cells. Extracts of Fe-MBGs at 0.1 and 1 mg/mL exhibited non-cytotoxicity and promoted cell proliferation. Additionally, extracts of Fe-MBGs at 1 mg/mL significantly enhanced the alkaline phosphatase activity of BMSCs and Saos-2 cells, along with an upregulation of the expression of osteogenesis-related genes. These findings unlock the significant potential of Fe-MBGs as functional biomaterials for bone regeneration applications. The controlled release of Fe ions from these mesoporous bioactive glasses orchestrates osteogenic differentiation in bone marrow mesenchymal stem cells and osteoblasts.

Deciphering Anion-Modulated Solvation Structure for Calcium Intercalation into Graphite for Ca-Ion Batteries.

Co-intercalation reactions make graphite a feasible anode in Ca ion batteries, yet the correlation between Ca ion intercalation behaviors and electrolyte structure remains unclear. This study, for the first time, elucidates the pivotal role of anions in modulating the Ca ion solvation structures and their subsequent intercalation into graphite. Specifically, the electrostatic interactions between Ca ion and anions govern the configurations of solvated-Ca-ion in dimethylacetamide-based electrolytes and graphite intercalation compounds. Among the anions considered (BH4 -, ClO4 -, TFSI- and [B(hfip)4]-), the coordination of four solvent molecules per Ca ion (CN=4) leads to the highest reversible capacities and the fastest reaction kinetics in graphite. Our study illuminates the origins of the distinct Ca ion intercalation behaviors across various anion-modulated electrolytes, employing a blend of experimental and theoretical approaches. Importantly, the practical viability of graphite anodes in Ca-ion full cells is confirmed, showing significant promise for advanced energy storage systems.