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FEBS Letters Sep 2020Life as we know it would not exist without water. However, water molecules not only serve as a solvent and reactant but can also promote hydrolysis, which counteracts... (Review)
Review
Life as we know it would not exist without water. However, water molecules not only serve as a solvent and reactant but can also promote hydrolysis, which counteracts the formation of essential organic molecules. This conundrum constitutes one of the central issues in origin of life. Hydrolysis is an important part of energy metabolism for all living organisms but only because, inside cells, it is a controlled reaction. How could hydrolysis have been regulated under prebiotic settings? Lower water activities possibly provide an answer: geochemical sites with less free and more bound water can supply the necessary conditions for protometabolic reactions. Such conditions occur in serpentinising systems, hydrothermal sites that synthesise hydrogen gas via rock-water interactions. Here, we summarise the parallels between biotic and abiotic means of controlling hydrolysis in order to narrow the gap between biochemical and geochemical reactions and briefly outline how hydrolysis could even have played a constructive role at the origin of molecular self-organisation.
Topics: Catalysis; Ferrosoferric Oxide; Geologic Sediments; Hydrogen; Hydrolysis; Hydrothermal Vents; Magnesium Hydroxide; Models, Chemical; Origin of Life; Seawater; Silicon Compounds; Water
PubMed: 32416624
DOI: 10.1002/1873-3468.13815 -
European Review For Medical and... Oct 2022Non-alcoholic fatty liver disease (NAFLD) still has no accepted pharmacological therapy. Even though monotherapy of L-carnitine or magnesium supplementation exhibits an... (Randomized Controlled Trial)
Randomized Controlled Trial
Hepatoprotective effect of combination of L-carnitine and magnesium-hydroxide in nonalcoholic fatty liver disease patients: a double-blinded randomized controlled pilot study.
OBJECTIVE
Non-alcoholic fatty liver disease (NAFLD) still has no accepted pharmacological therapy. Even though monotherapy of L-carnitine or magnesium supplementation exhibits an essential beneficial role in NAFLD treatment, and despite that new NAFLD treatment strategies focus on combination therapies, the combination of L-carnitine with magnesium has not yet been examined in NAFLD patients. We aimed to assess the efficacy of L-carnitine in combination with magnesium in NAFLD patients.
PATIENTS AND METHODS
Double-blinded, randomized controlled trial with 22 NAFLD participants who were randomized to either control group receiving placebo for the first 8 weeks and an additional 8 weeks with CIRRHOS product (2 gr L-carnitine and 150 mg magnesium) or treatment group receiving CIRRHOS product for 16 weeks. Weight, serum aspartate aminotransferase (AST), alanine transaminase (ALT) and C-reactive protein (CRP) levels were measured monthly. Lipid profile and serum insulin levels were monitored at baseline and at week 16 of treatment. Shear-wave elastography was used to evaluate liver stiffness (LS).
RESULTS
While AST and ALT levels decreased progressively over 16 weeks of treatment in the treatment group, AST and ALT levels of the control group were increased modestly or unaffected. AST and ALT levels of the treatment group decreased by 25% (p=0.9) and 20% (p=0.1) respectively, compared to AST and ALT levels at baseline. However, serum CRP levels, insulin levels, lipid profile and LS were not affected by treatment.
CONCLUSIONS
Our findings suggest that L-carnitine with magnesium supplementation could be a potential therapy for NAFLD. However, further studies with a larger population and high-sensitivity diagnostic parameters for early stages of NAFLD are needed to elucidate L-carnitine and magnesium efficacy in NAFLD.
Topics: Humans; Non-alcoholic Fatty Liver Disease; Carnitine; Magnesium; Pilot Projects; Magnesium Hydroxide; Alanine Transaminase; Aspartate Aminotransferases; Lipids; Insulins; Liver
PubMed: 36314323
DOI: 10.26355/eurrev_202210_30023 -
Journal of Tissue Engineering 2020Spinal fusion has become a common surgical technique to join two or more vertebrae to stabilize a damaged spine; however, the rate of pseudarthrosis (failure of fusion)...
Spinal fusion has become a common surgical technique to join two or more vertebrae to stabilize a damaged spine; however, the rate of pseudarthrosis (failure of fusion) is still high. To minimize pseudarthrosis, bone morphogenetic protein-2 (BMP2) has been approved for use in humans. In this study, we developed a poly(lactide-co-glycolide) (PLGA) composite incorporated with magnesium hydroxide (MH) nanoparticles for the delivery of BMP2. This study aimed to evaluate the effects of released BMP2 from BMP2-immobilized PLGA/MH composite scaffold in an in vitro test and an in vivo mice spinal fusion model. The PLGA/MH composite films were fabricated via solvent casting technique. The surface of the PLGA/MH composite scaffold was modified with polydopamine (PDA) to effectively immobilize BMP2 on the PLGA/MH composite scaffold. Analyzes of the scaffold revealed that using PLGA/MH-PDA improved hydrophilicity, degradation performance, neutralization effects, and increased BMP2 loading efficiency. In addition, releasing BMP2 from the PLGA/MH scaffold significantly promoted the proliferation and osteogenic differentiation of MC3T3-E1 cells. Furthermore, the pH neutralization effect significantly increased in MC3T3-E1 cells cultured on the BMP2-immobilized PLGA/MH scaffold. In our animal study, the PLGA/MH scaffold as a BMP2 carrier attenuates inflammatory responses and promotes BMP2-induced bone formation in posterolateral spinal fusion model. These results collectively demonstrate that the BMP2-immobilized PLGA/MH scaffold offers great potential in effectively inducing bone formation in spinal fusion surgery.
PubMed: 33178410
DOI: 10.1177/2041731420967591 -
Proceedings of the National Academy of... Aug 2022This study describes and demonstrates key steps in a carbon-negative process for manufacturing cement from widely abundant seawater-derived magnesium (Mg) feedstocks. In...
This study describes and demonstrates key steps in a carbon-negative process for manufacturing cement from widely abundant seawater-derived magnesium (Mg) feedstocks. In contrast to conventional Portland cement, which starts with carbon-containing limestone as the source material, the proposed process uses membrane-free electrolyzers to facilitate the conversion of carbon-free magnesium ions (Mg) in seawater into magnesium hydroxide [Mg(OH)] precursors for the production of Mg-based cement. After a low-temperature carbonation curing step converts Mg(OH) into magnesium carbonates through reaction with carbon dioxide (CO), the resulting Mg-based binders can exhibit compressive strength comparable to that achieved by Portland cement after curing for only 2 days. Although the proposed "cement-from-seawater" process requires similar energy use per ton of cement as existing processes and is not currently suitable for use in conventional reinforced concrete, its potential to achieve a carbon-negative footprint makes it highly attractive to help decarbonize one of the most carbon-intensive industries.
PubMed: 35972958
DOI: 10.1073/pnas.2114680119 -
Materials (Basel, Switzerland) Sep 2023The amount of waste heat generated annually in the UK exceeds the total annual electricity demand. Hence, it is crucial to effectively harness all available sources of...
The amount of waste heat generated annually in the UK exceeds the total annual electricity demand. Hence, it is crucial to effectively harness all available sources of waste heat based on their varying temperatures. Through suitable technologies, a substantial portion of this waste heat has the potential to be recovered for reutilization. Thermochemical energy storage (TCES) provides the best opportunities to recover waste heat at various temperatures for long-term storage and application. The potential of TCES with magnesium hydroxide, Mg(OH), has been established, but it has a relatively high dehydration temperature, thus limiting its potential for medium-temperature heat storage applications, which account for a vast proportion of industrial waste heat. To this end, samples of doped Mg(OH) with varying proportions (5, 10, 15, and 20 wt%) of potassium nitrate (KNO) have been developed and characterized for evaluation. The results showed that the Mg(OH) sample with 5 wt% KNO achieved the best outcome and was able to lower the dehydration temperature of the pure Mg(OH) from about 317 °C to 293 °C with an increase in the energy storage capacity from 1246 J/g to 1317 J/g. It also showed a monodisperse surface topology and thermal stability in the non-isothermal test conducted on the sample and therefore appears to have the potential for medium heat storage applications ranging from 293 °C to 400 °C.
PubMed: 37763573
DOI: 10.3390/ma16186296 -
Frontiers in Endocrinology 2022To describe the current knowledge on thyroid hormonal profile in patients on liquid L-T4 therapy and drugs known to interfere with L-T4 absorption. (Review)
Review
PURPOSE
To describe the current knowledge on thyroid hormonal profile in patients on liquid L-T4 therapy and drugs known to interfere with L-T4 absorption.
METHODS
A PubMed/MEDLINE, Web of Science, and Scopus research was performed. Case reports, case series, original studies and reviews written in English and published online up to 31 August 2022 were selected and reviewed. The final reference list was defined based on the relevance of each paper to the scope of this review.
RESULTS
The available data showed that novel levothyroxine formulations circumvent gastric pH impairment due to multiple interfering drugs such as proton pump inhibitors, calcium or iron supplements, sevelamer, aluminum/magnesium hydroxide and sodium alginate.
CONCLUSION
New formulations can be taken simultaneously with drugs interfering with L-T4 absorption, in particular liquid formulations. Softgel capsules need more studies to support these data.
Topics: Humans; Thyroxine; Drug Compounding; Thyroid Gland; Capsules; Proton Pump Inhibitors
PubMed: 36561558
DOI: 10.3389/fendo.2022.1080108 -
Translational Animal Science Jan 2021Supplemental sources of Mg can also aid in ruminal pH regulation due to their alkaline properties. Magnesium oxide (MgO) is the most common source of Mg for ruminants...
Supplemental sources of Mg can also aid in ruminal pH regulation due to their alkaline properties. Magnesium oxide (MgO) is the most common source of Mg for ruminants and can help controlling ruminal pH; however, the alkaline potential of other sources of Mg has not been evaluated. We aimed to evaluate the inclusion of calcium-magnesium carbonate (CaMg(CO)) and calcium-magnesium hydroxide (CaMg(OH)) alone or in combination as supplemental sources of Mg in corn silage-based diets and its impact on ruminal microbial fermentation. We hypothesized that inclusion of CaMg(OH) would allow for ruminal fermentation conditions resulting in a greater pH compared to the inclusion of CaMg(CO). Four treatments were defined by the supplemental source of Mg in the diet: 1) Control (100% MgO, plus sodium sesquicarbonate as a buffer); 2) CO [100% CaMg(CO)]; 3) OH [100% CaMg(OH)]; and 4) CO/OH [50% Mg from CaMg(CO), 50% Mg from CaMg(OH)]. Nutrient concentration was held constant across treatments (16% CP, 30% NDF, 1.66 Mcal NEl/kg, 0.67% Ca, and 0.21% Mg). Four fermenters were used in a 4 × 4 Latin square design with four periods of 10 d each. Samples were collected for analyses of nutrient digestibility, soluble Mg, VFA, and NH, while pH was measured at 0, 1, 2, 4, 6, 8, and 10 h post morning feeding to estimate % time when pH was below 6 (pH-B6) and area under the pH curve for pH below 6.0 (pH-AUC). Bacteria pellets were harvested for N analysis and estimates of N metabolism. Treatment effects were analyzed with the mixed procedure of SAS, while effects of using either CaMg(CO) or CaMg(OH) as Mg source in comparison to Control treatment were evaluated by orthogonal contrasts. Similar pH-related variables were observed for Control, OH, and CO/OH treatments, which had smaller pH-AUC and pH-B6 than CO ( ≤ 0.01). Butyrate molar proportion was greater in Control and CO/OH than in CO and OH ( = 0.04). Orthogonal contrasts showed lower flow of bacterial N ( = 0.04), lower butyrate molar proportion ( = 0.08) and greater pH-AUC ( = 0.05) for diets with CaMg(CO) in comparison with the Control. Concentration of soluble Mg in ruminal fluid ( = 0.73) and nutrient digestibility ( 0.52) were similar across treatments. Under the conditions of this experiment, using CaMg(OH) alone or combined with CaMg(CO) allowed for a less acidic ruminal fermentation pattern than a diet with only CaMg(CO).
PubMed: 33506181
DOI: 10.1093/tas/txaa229 -
Water Research Jul 2023Chemical dosing is the most used strategy for sulfide and methane abatement in urban sewer systems. Although conventional physicochemical methods, such as sulfide... (Review)
Review
Chemical dosing is the most used strategy for sulfide and methane abatement in urban sewer systems. Although conventional physicochemical methods, such as sulfide oxidation (e.g., oxygen/nitrate), precipitation (e.g., iron salts), and pH elevation (e.g., magnesium hydroxide/sodium hydroxide) have been used since the last century, the high chemical cost, large environmental footprint, and side-effects on downstream treatment processes demand a sustainable and cost-effective alternative to these approaches. In this paper, we aimed to review the currently used chemicals and significant progress made in sustainable sulfide and methane abatement technology, including 1) the use of bio-inhibitors, 2) in situ chemical production, and 3) an effective dosing strategy. To enhance the cost-effectiveness of chemical applications in urban sewer systems, two research directions have emerged: 1) online control and optimization of chemical dosing strategies and 2) integrated use of chemicals in urban sewer and wastewater treatment systems. The integration of these approaches offers considerable system-wide benefits; however, further development and comprehensive studies are required.
Topics: Sewage; Sulfides; Nitrates; Water Purification; Methane
PubMed: 37257296
DOI: 10.1016/j.watres.2023.120108 -
Nanomaterials (Basel, Switzerland) Feb 2023Although various caries-preventive agents have been developed, dental caries is still a leading global disease, mostly caused by biological factors such as mutans...
Although various caries-preventive agents have been developed, dental caries is still a leading global disease, mostly caused by biological factors such as mutans streptococci. Magnesium hydroxide nanoparticles have been reported to exhibit antibacterial effects; however, they are rarely used in oral care practical applications. In this study, we examined the inhibitory effect of magnesium hydroxide nanoparticles on biofilm formation by and -two typical caries-causing bacteria. Three different sizes of magnesium hydroxide nanoparticles (NM80, NM300, and NM700) were studied, all of which inhibited biofilm formation. The results showed that the nanoparticles were important for the inhibitory effect, which was not influenced by pH or the presence of magnesium ions. We also determined that the inhibition process was mainly contact inhibition and that medium (NM300) and large (NM700) sizes were particularly effective in this regard. The findings of our study demonstrate the potential applications of magnesium hydroxide nanoparticles as caries-preventive agents.
PubMed: 36903742
DOI: 10.3390/nano13050864 -
FEBS Letters Oct 2017Inorganic pyrophosphatases (PPases) convert pyrophosphate (PP ) to phosphate and are present in all cell types. Soluble PPases belong to three nonhomologous families, of... (Review)
Review
Inorganic pyrophosphatases (PPases) convert pyrophosphate (PP ) to phosphate and are present in all cell types. Soluble PPases belong to three nonhomologous families, of which Family II is found in approximately a quarter of prokaryotic organisms, often pathogenic ones. Each subunit of dimeric canonical Family II PPases is formed by two domains connected by a flexible linker, with the active site located between the domains. These enzymes require both magnesium and a transition metal ion (manganese or cobalt) for maximal activity and are the most active (k ≈ 10 s ) among all PPase types. Catalysis by Family II PPases requires four metal ions per substrate molecule, three of which form a unique trimetal center that coordinates the nucleophilic water and converts it to a reactive hydroxide ion. A quarter of Family II PPases contain an autoinhibitory regulatory insert formed by two cystathionine β-synthase (CBS) domains and one DRTGG domain. Adenine nucleotide binding either activates or inhibits the CBS domain-containing PPases, thereby tuning their activity and, hence, PP levels, in response to changes in cell energy status (ATP/ADP ratio).
Topics: Adenine Nucleotides; Bacteria; Biocatalysis; Catalytic Domain; Cobalt; Eukaryotic Cells; Gene Expression; Inorganic Pyrophosphatase; Isoenzymes; Kinetics; Magnesium; Manganese; Models, Molecular; Protein Domains; Protein Multimerization; Protein Structure, Secondary; Protein Structure, Tertiary; Protein Subunits
PubMed: 28986979
DOI: 10.1002/1873-3468.12877