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1.
BMC Pregnancy Childbirth ; 24(1): 318, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664622

RESUMEN

BACKGROUND: Some studies have compared the efficacy of nifedipine with that of other tocolytic drugs in the treatment of preterm labor, but the reported results are conflicting. OBJECTIVE: To compare the efficacy of nifedipine with that of ritodrine, nitroglycerine and magnesium sulfate for the management of preterm labor. METHODS: In this systematic review and meta-analysis, PubMed/MEDLINE, Scopus, Clarivate Analytics Web of Science, and Google Scholar were searched until April 3,2024 using predefined keywords. Randomized controlled trials (RCTs) and clinical trials that compared the efficacy of nifedipine with that of ritodrine, nitroglycerine and magnesium sulfate for the management of preterm labor were included. Two authors independently reviewed the articles, assessed their quality and extracted the data. The quality of the included RCTs based on the Cochrane Risk of Bias Tool 1 for clinical trial studies. The risk difference (RD) with the associated 95% confidence interval (CI) was calculated. A forest plot diagram was used to show the comparative point estimates of nifedipine and other tocolytic drugs on the prevention of preterm labor and their associated 95% confidence intervals based on the duration of pregnancy prolongation. Study heterogeneity was evaluated by the I2 index, and publication bias was evaluated by Egger's test. RESULTS: Forty studies enrolling 4336 women were included. According to our meta-analysis, there was a significant difference in the prolongation of preterm labor within the first 48 h between the nifedipine group and the nitroglycerine group (RD, -0.04; 95% CI, -0.08 to -0.00; I2: 32.3%). Additionally, there were significant differences between nifedipine and ritodrine (RD, 0.11; 95% CI, 0.02 to 0.21; I2, 51.2%) for more than one week RD, 0.10; 95% CI, 0.03 to 0.19; I2, 33.2%) and for 34 weeks and more. The difference between nifedipine and magnesium sulfate was not significant in any of the four time points. CONCLUSIONS: Considering the superiority of nifedipine over ritodrine and nitroglycerine and its similar efficacy to magnesium sulfate for tocolysis, it seems that the side effects of these options determine the first drug line.


Asunto(s)
Sulfato de Magnesio , Nifedipino , Nitroglicerina , Trabajo de Parto Prematuro , Ritodrina , Tocolíticos , Humanos , Nifedipino/uso terapéutico , Femenino , Embarazo , Trabajo de Parto Prematuro/tratamiento farmacológico , Sulfato de Magnesio/uso terapéutico , Ritodrina/uso terapéutico , Tocolíticos/uso terapéutico , Nitroglicerina/uso terapéutico , Resultado del Tratamiento , Ensayos Clínicos Controlados Aleatorios como Asunto
2.
Front Physiol ; 15: 1363975, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38665599

RESUMEN

Hypertension is associated with increased risk of cardiovascular disease and death. Evidence suggests that Mg2+ depletion contributes to hypertension. It is estimated that 25% or more of the United States population experiences chronic, latent Mg2+ depletion. This review explores mechanisms by which Mg2+ influences blood pressure, modifying risk of hypertension and complicating its treatment. Mechanisms addressed include effects upon i) sympathetic tone, via the modulation of N-methyl-D-aspartate (NMDA) receptor and N-type Ca2+ channel activity, influencing catecholamine release from sympathetic nerve endings; ii) vascular tone, via alteration of L-type Ca2+ and endothelial nitric oxide synthase (eNOS) activity and prostacyclin release; iii) renal K+ handling, influencing systemic K+ balance and potentially indirectly influencing blood pressure; iv) aldosterone secretion from the adrenal cortex; and v) modulation of pro-hypertensive inflammatory processes in dendritic cells and macrophages, including activation of the NLR family pyrin domain containing 3 (NLRP3) inflammasome and stimulation of isolevuglandin (IsoLG) production. Discovery of these mechanisms has furthered our understanding of the pathogenesis of hypertension, with implications for treatment and has highlighted the role of Mg2+ balance in hypertension and cardiovascular disease.

3.
Cureus ; 16(3): e56388, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38633975

RESUMEN

Aim The study aims to characterize Fe and Mg co-substituted hydroxyapatite nanoparticles (FeMgHAPn) and assess the antimicrobial properties of FeMgHAPn-incorporated orthodontic composite. Materials and methods FeMgHAPn was synthesized using the sol-gel method, and the prepared nanoparticle powder was characterized using Fourier Transform Infrared Spectroscopy (FTIR), energy-dispersive X-ray analysis (EDX)) and scanning electron microscopic (SEM) analysis. The FeMgHAPn was incorporated into a commercially available orthodontic composite in two concentrations (40 and 20 µL), and the structure was examined using SEM. The FeMgHAPn-incorporated composite was tested for its antimicrobial efficacy against Streptococcus mutans, Staphylococcus aureus, and Escherichia coli using the agar-well diffusion method. The zones of inhibition (ZOI) were measured in millimeters (mm). Results The characterization of the FeMgHAPn indicated the successful formation of the nanoparticle without any impurities or byproducts. The high concentration (40 µL) of FeMgHAPn-incorporated orthodontic composite showed the maximum ZOI against all three microbes, followed by the low concentration (20 µL) and the control group. Conclusion The FeMgHAPn-incorporated orthodontic composite showed promising antimicrobial activity against caries-causing S. mutans, S. aureus, and E. coli.

4.
Anal Bioanal Chem ; 416(12): 2941-2949, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38594392

RESUMEN

Messenger RNA (mRNA) vaccines represent a landmark in vaccinology, especially with their success in COVID-19 vaccines, which have shown great promise for future vaccine development and disease prevention. As a platform technology, synthetic mRNA can be produced with high fidelity using in vitro transcription (IVT). Magnesium plays a vital role in the IVT process, facilitating the phosphodiester bond formation between adjacent nucleotides and ensuring accurate transcription to produce high-quality mRNA. The development of the IVT process has prompted key inquiries about in-process characterization of magnesium ion (Mg++) consumption, relating to the RNA polymerase (RNAP) activation, fed-batch mode production yield, and mRNA quality. Hence, it becomes crucial to monitor the free Mg++ concentration throughout the IVT process. However, no free Mg++ analysis method has been reported for complex IVT reactions. Here we report a robust capillary zone electrophoresis (CZE) method with indirect UV detection. The assay allows accurate quantitation of free Mg++ for the complex IVT reaction where it is essential to preserve IVT samples in their native-like state during analysis to avoid dissociation of bound Mg complexes. By applying this CZE method, the relationships between free Mg++ concentration, the mRNA yield, and dsRNA impurity level were investigated. Such mechanistic understanding facilitates informed decisions regarding the quantity and timing of feeding starting materials to increase the yield. Furthermore, this approach can serve as a platform method for analyzing the free Mg++ in complex sample matrices where preserving the native-like state of Mg++ binding is key for accurate quantitation.


Asunto(s)
Electroforesis Capilar , Magnesio , ARN Mensajero , Transcripción Genética , Electroforesis Capilar/métodos , Magnesio/análisis , ARN Mensajero/genética , ARN Mensajero/análisis , SARS-CoV-2/genética , Humanos
5.
World J Orthop ; 15(3): 215-229, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38596190

RESUMEN

BACKGROUND: In recent years, the use of Magnesium alloy implants have gained renewed popularity, especially after the first commercially available Conformité Européenne approved Magnesium implant became available (MAGNEZIX® CS, Syntellix) in 2013. AIM: To document our clinical and radiographical outcomes using magnesium implants in treating peri-articular elbow fractures. METHODS: Our paper was based on a retrospective case series design. Intra-operatively, a standardized surgical technique was utilized for insertion of the magnesium implants. Post - operatively, clinic visits were standardized and physical exam findings, functional scores, and radiographs were obtained at each visit. All complications were recorded. RESULTS: Five patients with 6 fractures were recruited (2 coronoid, 3 radial head and 1 capitellum). The mean patient age and length of follow up was 54.6 years and 11 months respectively. All fractures healed, and none exhibited loss of reduction or complications requiring revision surgery. No patient developed synovitis of the elbow joint or suffered electrolytic reactions when titanium implants were used concurrently. CONCLUSION: Although there is still a paucity of literature available on the subject and further studies are required, magnesium implants appear to be a feasible tool for fixation of peri-articular elbow fractures with promising results in our series.

6.
Am J Clin Nutr ; 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38599521

RESUMEN

BACKGROUND: Hypomagnesemia is commonly observed in individuals with diabetes, but how diabetes medications alter magnesium (Mg) status remains unclear. OBJECTIVES: We aimed to examine the association between diabetes medication and hypomagnesemia and evaluate whether serum Mg mediates the association between diabetes medication and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) in a prospective cohort. METHODS: Adults from the Boston Puerto Rican Health Study were included (n = 1106). Multivariable logistic regression models were used to estimate odds ratio (OR) and 95% confidence interval (CI) for cross-sectional association between diabetes medication and hypomagnesemia (serum Mg <0.75 mmol/L). Longitudinal mediation analysis was performed to evaluate the direct and indirect (via serum Mg) associations between diabetes medication and 4-y HOMA-IR in 341 participants with baseline hemoglobin A1c of (HbA1c) ≥6.5%. RESULTS: Mean age at baseline was 59.0 ± 7.6 y, with 28.0% male and 45.8% with hypomagnesemia. Use of metformin [OR (95% CI: 3.72 (2.53, 5.48)], sulfonylureas [OR (95% CI) = 1.68 (1.00, 2.83)], and glitazones [OR (95% CI) = 2.09 (1.10, 3.95)], but not insulin, was associated with higher odds of hypomagnesemia. Use of multiple diabetes medications and longer duration of use were associated with higher odds of hypomagnesemia. Serum Mg partially mediated the association between metformin and HOMA-IR [indirect association: ß (95% CI) = 1.11 (0.15, 2.07)], which weakened the direct association [ß (95% CI) = -5.16 (-9.02, -1.30)] by 22% [total association: ß (95% CI) = -4.05 (-7.59, -0.51)]. Similarly, serum Mg mediated 17% of the association between sulfonylureas and elevated HOMA-IR. However, the mediation by serum Mg was weak for insulin and glitazones. CONCLUSIONS: Diabetes medication, especially metformin, was associated with elevated odds of hypomagnesemia, which may weaken the association between metformin and lowering of HOMA-IR. The causal inference needs to be confirmed in further studies.

7.
Cell Rep ; 43(4): 114108, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38615321

RESUMEN

TRP channels are implicated in various diseases, but high structural similarity between them makes selective pharmacological modulation challenging. Here, we study the molecular mechanism underlying specific inhibition of the TRPM7 channel, which is essential for cancer cell proliferation, by the anticancer agent CCT128930 (CCT). Using cryo-EM, functional analysis, and MD simulations, we show that CCT binds to a vanilloid-like (VL) site, stabilizing TRPM7 in the closed non-conducting state. Similar to other allosteric inhibitors of TRPM7, NS8593 and VER155008, binding of CCT is accompanied by displacement of a lipid that resides in the VL site in the apo condition. Moreover, we demonstrate the principal role of several residues in the VL site enabling CCT to inhibit TRPM7 without impacting the homologous TRPM6 channel. Hence, our results uncover the central role of the VL site for the selective interaction of TRPM7 with small molecules that can be explored in future drug design.


Asunto(s)
1-Naftilamina/análogos & derivados , Antineoplásicos , Canales Catiónicos TRPM , Canales Catiónicos TRPM/metabolismo , Canales Catiónicos TRPM/antagonistas & inhibidores , Humanos , Antineoplásicos/farmacología , Antineoplásicos/química , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Células HEK293 , Simulación de Dinámica Molecular , Sitios de Unión , Unión Proteica , Microscopía por Crioelectrón
8.
Front Physiol ; 15: 1363708, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38638279

RESUMEN

Osteoporosis after bariatric surgery is an increasing health concern as the rate of bariatric surgery has risen. In animal studies mimicking bariatric procedures, bone disease, together with decreased serum levels of Ca2+, Mg2+ and the gastric hormone Ghrelin were described. Ghrelin regulates metabolism by binding to and activating the growth hormone secretagogue receptor (GHSR) which is also expressed in the kidney. As calcium and magnesium are key components of bone, we tested the hypothesis that Ghrelin-deficiency contributes to osteoporosis via reduced upregulation of the renal calcium channel TRPV5 and the heteromeric magnesium channel TRPM6/7. We expressed GHSR with TRPV5 or TRPM6/7 channel in HEK293 cells and treated them with purified Ghrelin. Whole-cell current density was analyzed by patch-clamp recording. Nephron-specific gene expression was performed by tubular microdissection followed by qPCR in wild-type (WT) mice, and immunofluorescent imaging of GHSR-eGFP mice. Tubular magnesium homeostasis was analyzed in GHSR-null and WT mice at baseline and after caloric restriction. After Ghrelin exposure, whole-cell current density did not change for TRPV5 but increased for TRPM6/7 in a dose-dependent fashion. Applying the Ghrelin-mimetic (D-Trp7, Ala8,D-Phe10)-α-MSH (6-11) amide without and with the GHSR antagonist (D-Lys3)-GHRP6, we confirmed the stimulatory role of Ghrelin towards TRPM6/7. As GHSR initiates downstream signaling via protein kinase A (PKA), we found that the PKA inhibitor H89 abrogated TRPM6/7 stimulation by Ghrelin. Similarly, transfected Gαs, but not the Gαs mutant Q227L, nor Gαi2, Gαq, or Gα13 upregulated TRPM6/7 current density. In microdissected TALs and DCTs similar levels of GHSR mRNA were detected. In contrast, TRPM6 mRNA was expressed in the DCT and also detected in the TAL at 25% expression compared to DCT. Immunofluorescent studies using reporter GHSR-eGFP mice showed a strong eGFP signal in the TAL but surprisingly displayed no eGFP signal in the DCT. In 3-, 6-, and 9-month-old GHSR-null and WT mice, baseline serum magnesium was not significantly different, but 24-h urinary magnesium excretion was elevated in 9-month-old GHSR-null mice. In calorically restricted GHSR-null mice, we detected excess urinary magnesium excretion and reduced serum magnesium levels compared to WT mice. The kidneys from calorically restricted WT mice showed upregulated gene expression of magnesiotropic genes Hnf1b, Cldn-16, Cldn-19, Fxyd-2b, and Parvalbumin compared to GHSR-null mice. Our in vitro studies show that Ghrelin stimulates TRPM6/7 via GHSR and Gαs-PKA signaling. The murine studies are consistent with Ghrelin-GHSR signaling inducing reduced urinary magnesium excretion, particularly in calorically restricted mice when Ghrelin levels are elevated. This effect may be mediated by Ghrelin-upregulation of TRPM6 in the TAL and/or upregulation of other magnesiotropic genes. We postulate that rising Ghrelin levels with hunger contribute to increased renal Mg2+ reabsorption to compensate for lack of enteral Mg2+ uptake.

9.
Virol J ; 21(1): 91, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654355

RESUMEN

BACKGROUND: This study sought to examine the impact of magnesium supplementation on clinical outcomes and biochemical factors among hospitalized patients with COVID-19. METHODS: This double-blind, randomized clinical trial was conducted at Razi Hospital, Ahvaz, Iran, between September 2021 and March 2022. Participants aged 18-70 years with moderate disease severity were enrolled. Magnesium supplementation (300 mg daily) was administered to the intervention group, while the control group received a placebo. Clinical outcomes, including the need for oxygen therapy, oxygen saturation, respiratory rate, fever, hs-CRP and TNF-α levels, as well as quality of life and mental health, were assessed. Blood samples were collected to measure biochemical variables. RESULTS: The main result was the count of individuals requiring oxygen therapy. Additional outcomes comprised of oxygen saturation, respiratory rate, fever, hs-CRP and TNF-α levels, as well as quality of life and mental health. Out of 64 participants, 60 completed the study. The results showed that magnesium supplementation significantly reduced the number of patients requiring oxygen therapy (9 vs. 14; P < 0.001). Moreover, the magnesium group demonstrated improved oxygen saturation compared to the control group (4.55 ± 2.35 vs. 1.8 ± 1.67; P < 0.001). Furthermore, we observed a noteworthy enhancement in the quality of life and depression score in the magnesium group. No significant differences were observed in respiratory rate, fever, hs-CRP, and TNF-α levels (P > 0.05). CONCLUSION: The findings suggest that magnesium supplementation may have beneficial effects on clinical outcomes and arterial oxygen saturation in COVID-19 patients. More investigation is necessary to delve into its potential mechanisms and long-term effects on patient outcomes. TRIAL REGISTRATION: This study is registered on Iranian Registry of Clinical Trials (IRCT) under identifier IRCT20210413050957N1. (The registration date: May 1, 2021).


Asunto(s)
COVID-19 , Suplementos Dietéticos , Magnesio , Calidad de Vida , Humanos , Persona de Mediana Edad , Masculino , Femenino , Adulto , Magnesio/sangre , Magnesio/administración & dosificación , COVID-19/sangre , Método Doble Ciego , Irán , Anciano , Adulto Joven , SARS-CoV-2 , Adolescente , Tratamiento Farmacológico de COVID-19 , Resultado del Tratamiento , Proteína C-Reactiva/análisis , Factor de Necrosis Tumoral alfa/sangre
10.
Sci Rep ; 14(1): 9412, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38658625

RESUMEN

Textile industry dye effluent contains a mixture of different kinds of dyes. Many times, photocatalysis is targeted as a solution for the treatment of dye effluent from the textile industry. Many researches have been published related to the photocatalysis of single textile dyes but in the real-world scenario, effluent is a mixture of dyes. Magnesium oxide (MgO) is used as a photocatalyst to treat a mixture (binary solution) of Methylene blue (MB) and Methylene violet (MV) along with individual MB and MV dyes in this article. MgO shows remarkable photocatalytic activity at about 93 and 88% for MB and MV dye in binary solution within 135 min. Furthermore, to study the influence of process parameters, experiments are designed with the help of the central composite design (CCD), and Response surface methodology (RSM) is used to study the interactions between parameters. For this study, five parameters are selected i.e., Photocatalyst dosage, initial concentration of both dyes, time of exposure to the light source, and pH of the binary solution. The photocatalytic process is also optimized and finally optimization of process parameters is validated with an experiment. The result of the validation experiment is very close to the predicted photocatalytic activity.

11.
Front Pharmacol ; 15: 1341799, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38659572

RESUMEN

Tetraethylammonium (TEA), a quaternary ammonium compound, is a well-known blocker of potassium channels belonging to various subfamilies, such as KV1-3, KCa1, 2 and prokaryotic KcsA. In many cases, TEA acts from the extracellular side by open pore blockade. TEA can also block transient receptor potential (TRP) cation channels, such as TRPM7, in a voltage-dependent manner. In human T lymphocytes, intracellular (cytosolic) TEA and its analog TMA (tetramethylammonium) inhibit TRPM7 channel currents in the outward but not inward direction. By contrast, intracellular Mg2+, protons and polyamines inhibit both outward and inward current components equally. Likewise, the majority of available pharmacological tools inhibit TRPM7 channels in a voltage-independent manner. Since TRPM7 is a steeply outwardly rectifying conductance, voltage-dependent blockers can be useful for studying the cellular functions of this channel. TRPM7 protein is endogenously expressed in diverse cell lines, including HEK, HeLa, CHO, RBL and Jurkat. Using patch-clamp electrophysiology, we found that incubating HEK293 and Jurkat T cells overnight in the presence of 20 mM TEA-Cl, resulted in the nearly complete blockade of whole-cell TRPM7 outward current, measured at break-in. By contrast, the inward current was unchanged in TEA-loaded cells. The blockade was fully reversible after washout of intracellular solution in whole-cell but not in perforated-patch recording configurations. Overnight incubation with 20 mM TMA-Cl resulted in a more modest blockade of the outward TRPM7 current. Internal 129 mM TMA and TEA eliminated most of the outward current. TEA uptake in transfected HEK293 cells led to blockade of recombinant murine TRPM7 and the Mg2+ and pH insensitive Ser1107Arg variant. Unexpectedly, Tris-HCl, a widely used pH buffer, could similarly be loaded into Jurkat and HEK cells, and preferentially blocked outward TRPM7 currents. 20 mM and 129 mM Tris in the internal solution blocked TRPM7 current in outward but not inward direction. Voltage-dependent channel blockade by TEA, TMA and Tris loading will be useful for studying the properties and functions of TRPM7-mediated ion transport in intact cells.

12.
Diagnostics (Basel) ; 14(8)2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38667486

RESUMEN

One of the main causes of the dismal prognosis in patients who survive the initial bleeding after aneurysmal subarachnoidal hemorrhage is the delayed cerebral ischaemia caused by vasospasm. Studies suggest that cerebral magnesium and pH may potentially play a role in the pathophysiology of this adverse event. Using phosphorous magnetic resonance spectrocopy (31P-MRS), we calculated the cerebral magnesium (Mg) and pH levels in 13 patients who suffered from aSAH. The values between the group that developed clinically significant vasospasm (n = 7) and the group that did not (n = 6) were compared. The results of this study show significantly lower cerebral Mg levels (p = 0.019) and higher pH levels (p < 0.001) in the cumulative group (all brain voxels together) in patients who developed clinically significant vasospasm. Further clinical studies on a larger group of carefully selected patients are needed in order to predict clinically significant vasospasm.

13.
J Funct Biomater ; 15(4)2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38667545

RESUMEN

Nerve guidance conduits for peripheral nerve injuries can be improved using bioactive materials such as magnesium (Mg) and its alloys, which could provide both structural and trophic support. Therefore, we investigated whether exposure to Mg and Mg-1.6wt%Li thin films (Mg/Mg-1.6Li) would alter acute Schwann cell responses to injury. Using the RT4-D6P2T Schwannoma cell line (SCs), we tested extracts from freeze-killed cells (FKC) and nerves (FKN) as in vitro injury stimulants. Both FKC and FKN induced SC release of the macrophage chemoattractant protein 1 (MCP-1), a marker of the repair SC phenotype after injury. Next, FKC-stimulated cells exposed to Mg/Mg-1.6Li reduced MCP-1 release by 30%, suggesting that these materials could have anti-inflammatory effects. Exposing FKC-treated cells to Mg/Mg-1.6Li reduced the gene expression of the nerve growth factor (NGF), glial cell line-derived neurotrophic factor (GDNF), and myelin protein zero (MPZ), but not the p75 neurotrophin receptor. In the absence of FKC, Mg/Mg-1.6Li treatment increased the expression of NGF, p75, and MPZ, which can be beneficial to nerve regeneration. Thus, the presence of Mg can differentially alter SCs, depending on the microenvironment. These results demonstrate the applicability of this in vitro nerve injury model, and that Mg has wide-ranging effects on the repair SC phenotype.

14.
Nanomaterials (Basel) ; 14(8)2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38668152

RESUMEN

A composite material composed of anodized aluminum oxide (AAO), carbon (C), and magnesium oxide (MgO) was developed for CO2 capture applications. Inspired by the bryophyte organism, the AAO/C/MgO composite mirrors two primary features of these species-(1) morphological characteristics and (2) elemental composition-specifically carbon, oxygen, and magnesium. The synthesis process involved two sequential steps: electroanodization of aluminum foil followed by a hydrothermal method using a mixture of glucose and magnesium chloride (MgCl2). The concentration of MgCl2 was systematically varied as the sole experimental variable across five levels-1 mM, 2 mM, 3 mM, 4 mM, and 5 mM-to investigate the impact of MgO formation on the samples' chemical and physical properties, and consequently, their CO2 capture efficiency. Thus, scanning electron microscopy analysis revealed the AAO substrate's porous structure, with pore diameters measuring 250 ± 30 nm. The growth of MgO on the AAO substrate resulted in spherical structures, whose diameter expanded from 15 nm ± 3 nm to 1000 nm ± 250 nm with increasing MgCl2 concentration from the minor to major concentrations explored, respectively. X-ray photoelectron spectroscopy (XPS) analysis indicated that carbon serves as a linking agent between AAO and MgO within the composite. Notably, the composite synthesized with a 4 mM MgCl2 concentration exhibited the highest CO2 capture efficiency, as determined by UV-Vis absorbance studies using a sodium carbonate solution as the CO2 source. This efficiency was quantified with a 'k' constant of 0.10531, significantly higher than those of other studied samples. The superior performance of the 4 mM MgCl2 sample in CO2 capture is likely due to the optimal density of MgO structures formed on the sample's surface, enhancing its adsorptive capabilities as suggested by the XPS results.

15.
Nanomaterials (Basel) ; 14(8)2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38668173

RESUMEN

This work reports on the design, development, and characterization of novel magneto-plasmonic elastic liposomes (MPELs) of DPPC:SP80 (85:15) containing Mg0.75Ca0.25Fe2O4 nanoparticles coupled with gold nanorods, for topical application of photothermal therapy (PTT). Both magnetic and plasmonic components were characterized regarding their structural, morphological, magnetic and photothermal properties. The magnetic nanoparticles display a cubic shape and a size (major axis) of 37 ± 3 nm, while the longitudinal and transverse sizes of the nanorods are 46 ± 7 nm and 12 ± 1.6 nm, respectively. A new methodology was employed to couple the magnetic and plasmonic nanostructures, using cysteine as bridge. The potential for photothermia was evaluated for the magnetic nanoparticles, gold nanorods and the coupled magnetic/plasmonic nanoparticles, which demonstrated a maximum temperature variation of 28.9 °C, 33.6 °C and 37.2 °C, respectively, during a 30 min NIR-laser irradiation of 1 mg/mL dispersions. Using fluorescence anisotropy studies, a phase transition temperature (Tm) of 35 °C was estimated for MPELs, which ensures an enhanced fluidity crucial for effective crossing of the skin layers. The photothermal potential of this novel nanostructure corresponds to a specific absorption rate (SAR) of 616.9 W/g and a maximum temperature increase of 33.5 °C. These findings point to the development of thermoelastic nanocarriers with suitable features to act as photothermal hyperthermia agents.

16.
World J Microbiol Biotechnol ; 40(6): 182, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38668902

RESUMEN

The effect of barium ions on the biomineralization of calcium and magnesium ions is often overlooked when utilizing microbial-induced carbonate precipitation technology for removing barium, calcium, and magnesium ions from oilfield wastewater. In this study, Bacillus licheniformis was used to bio-precipitate calcium, magnesium, and barium ions. The effects of barium ions on the physiological and biochemical characteristics of bacteria, as well as the components of extracellular polymers and mineral characteristics, were also studied in systems containing coexisting barium, calcium, and magnesium ions. The results show that the increasing concentrations of barium ions decreased pH, carbonic anhydrase activity, and concentrations of bicarbonate and carbonate ions, while it increased the contents of humic acids, proteins, polysaccharides, and DNA in extracellular polymers in the systems containing all three types of ions. With increasing concentrations of barium ions, the content of magnesium within magnesium-rich calcite and the size of minerals precipitated decreased, while the full width at half maximum of magnesium-rich calcite, the content of O-C=O and N-C=O, and the diversity of protein secondary structures in the minerals increased in systems containing all three coexisting ions. Barium ions does inhibit the precipitation of calcium and magnesium ions, but the immobilized bacteria can mitigate the inhibitory effect. The precipitation ratios of calcium, magnesium, and barium ions reached 81-94%, 68-82%, and 90-97%. This research provides insights into the formation of barium-enriched carbonate minerals and offers improvements for treating oilfield wastewater.


Asunto(s)
Bacillus licheniformis , Bario , Biomineralización , Calcio , Magnesio , Magnesio/metabolismo , Bacillus licheniformis/metabolismo , Bario/metabolismo , Calcio/metabolismo , Aguas Residuales/microbiología , Aguas Residuales/química , Concentración de Iones de Hidrógeno , Iones , Anhidrasas Carbónicas/metabolismo , Carbonato de Calcio/metabolismo
17.
Int J Biol Macromol ; 267(Pt 2): 131412, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38593894

RESUMEN

The synthesis of ideal bioceramics to guide the fate of cells and subsequent bone regeneration within the chemical, biological, and physical microenvironment is a challenging long-term task. This study developed amorphous calcium magnesium phosphate (ACMP) bioceramics via a simple co-precipitation method. The role of Mg2+ in the formation of ACMP is investigated using physicochemical and biological characterization at different Ca/Mg molar ratio of the initial reaction solution. Additionally, ACMP bioceramics show superior cytocompatibility and improved osteogenic differentiation of co-cultured MC3T3-E1 cells. Regulation of the microenvironment with Mg2+ can promote early-stage bone regeneration. For this, bioprinting technology is employed to prepare ACMP-modified 3D porous structures. Our hypothesis is that the incorporation of ACMP into methacrylated gelatin (GelMA) bioink can trigger the osteogenic differentiation of encapsulated preosteoblast and stimulate bone regeneration. The cell-laden ACMP composite structures display stable printability and superior cell viability and cell proliferation. Also, constructs loading the appropriate amount of ACMP bioceramic showed significant osteogenic differentiation activity compared to the pure GelMA. We demonstrate that the dissolved Mg2+ cation microenvironment in ACMP-modified composite constructs plays an effective biochemical role, and can regulate cell fate. Our results predict that GelMA/ACMP bioink has significant potential in patient-specific bone tissue regeneration.

18.
Nano Lett ; 24(15): 4400-4407, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38568187

RESUMEN

We developed a magnesium/sodium (Mg/Na) hybrid battery using a hierarchical disk-whisker FeSe2 architecture (HD-FeSe2) as the cathode material and a modified dual-ion electrolyte. The polarizable Se2- anion reduced the Mg2+ migration barrier, and the 3D configuration possessed a large surface area, which facilitated both Mg2+/Na+ cation diffusion and electron transport. The dual-ion salts with NaTFSI in ether reduced the Mg plating/stripping overvoltage in a symmetric cell. The hybrid battery exhibited an energy density of 260.9 Wh kg-1 and a power density of 600.8 W kg-1 at 0.2 A g-1. It showed a capacity retention of 154 mAh g-1 and a Coulombic efficiency of over 99.5% under 1.0 A g-1 after 800 long cycles. The battery also displayed outstanding temperature tolerance. The findings of 3D architecture as cathode material and hybrid electrolyte provide a pathway to design a highly reliable Mg/Na hybrid battery.

19.
ACS Appl Mater Interfaces ; 16(15): 19014-19025, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38573769

RESUMEN

Rechargeable magnesium batteries (RMBs) are one of the most promising "post-lithium" battery technologies, but the electrochemical performance is still far from expectation due to the sluggish reaction kinetics of divalent Mg2+ ions. Herein, we report a low-cost, high-performance Mg-organic battery based on the combination of a fluorinated alkoxyaluminate electrolyte and a carbonyl polymer cathode material. First, the one-pot synthesized Mg[Al(HFIP)4]2 (HFIP = hexafluoro-2-propanol) is proved superior to the Mg[B(HFIP)4]2 analogue in both Mg anode compatibility and electrochemical window, as the electrolyte salt in the G2-DME (G2 = diethylene glycol dimethyl ether; DME = 1,2-dimethoxyethane) mixture solvent. Second, a simple wet grinding method is proposed to effectively improve the dispersion uniformity of the poly(benzoquinone-pyrrole) (PBQPy) active material in the cathode. Third, the elaborate Mg-PBQPy battery exhibits superior electrochemical performance within 0.4-3.0 V, including a high reversible capacity of 197 mA h g-1, a high average discharge voltage of 1.6 V, and a high capacity retention of 71% after 500 cycles. Finally, based on various electrochemical analysis and ex situ characterization results, we propose a general microscopic structure evolution model to reveal the electrochemical behaviors of carbonyl polymer cathode in RMBs, including the swelling of polymer active material, trapping of Mg2+ ions, and reversible redox reaction.

20.
Drug Des Devel Ther ; 18: 919-929, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38560523

RESUMEN

Background: Magnesium sulfate, an intravenous adjuvant, has recently attracted immense attention in multimodal analgesia. Previous studies confirmed the crucial role of magnesium sulfate in postoperative pain and nociceptive hypersensitivity. However, the effect of magnesium sulfate in multimodal analgesia on the quality of recovery (QoR) for elderly patients has not been thoroughly studied. Therefore, the present experiment aimed to investigate the effect of continuous intravenous magnesium sulfate on the quality of postoperative recovery in elderly patients undergoing total knee arthroplasty (TKA). Patients and Methods: In this study, a total of 148 patients scheduled to undergo unilateral total knee arthroplasty were randomized into a magnesium sulfate group (Group M, n=68) and a control group (Group C, n=66) using a double-blind, randomized controlled trial. Before induction of anesthesia, Group M received intravenous magnesium sulfate (40 mg/kg) for 15 min, followed by a continuous infusion (15 mg/kg) until the end of the procedure. In the same manner, Group C received an infusion of the same amount of isotonic saline using the same method as the Group M. Results: Compared with Group C, Group M had significantly better QoR-15 scores on postoperative day 1(POD1) than Group C (P <0.05). Analysis of the dimensions of QoR-15 scores indicated that Group M exhibited notably reduced levels of pain, and higher levels of emotional state and physical comfort than Group C (P <0.05). Furthermore, Group C had significantly higher numerical rating scale (NRS) scores at POD1 than Group M (P <0.05). Conclusion: For elderly patients undergoing knee arthroplasty, magnesium sulfate can be used as an adjuvant in a multimodal analgesic regimen to reduce early postoperative pain and improve the quality of early postoperative recovery.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Sulfato de Magnesio , Humanos , Anciano , Sulfato de Magnesio/uso terapéutico , Estudios Prospectivos , Analgésicos , Dolor Postoperatorio/tratamiento farmacológico , Método Doble Ciego , Analgésicos Opioides
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