Pyrolysis of High-Ash Natural Microalgae from Water Blooms: Effects of Acid Pretreatment.

Natural microalgae (NA, cyanobacteria) collected from Taihu Lake (Jiangsu, China) were used for biofuel production through pyrolysis. The microalgae were de-ashed via pretreatment with deionized water and hydrochloric acid, and the samples obtained were noted as 0 M, 0.1 M, 1 M, 2 M, 4 M, 6 M, 8 M, respectively, according to the concentration of hydrochloric acid used in the pretreatment. Pyrolysis experiments were carried out at 500 °C for 2 h. The products were examined by various techniques to identify the influence of the ash on the pyrolysis behavior. The results showed that the ash inhibited the thermal transformation of microalgae. The 2 mol/L hydrochloric acid performed the best in removing ash and the liquid yield increased from 34.4% (NA) to 40.5% (2 M). Metal-oxides (mainly CaO, MgO, Al2O3) in ash promoted the reaction of hexadecanoic acid and NH3 to produce more hexadecanamide, which was further dehydrated to hexadecanenitrile. After acid pretreatment, significant improvement in the selectivity of hexadecanoic acid was observed, ranging from 22.4% (NA) to 58.8% (4 M). The hydrocarbon compounds in the liquid product increased from 12.90% (NA) to 26.67% (2 M). Furthermore, the acid pretreatment enhanced the content of C9-C16 compounds and the HHV values of bio-oil. For natural microalgae, the de-ashing pretreatment before pyrolysis was essential for improving the biocrude yield and quality, as well as the biomass conversion efficiency.

Magnesium Oxide in Constipation.

Magnesium oxide has been widely used as a laxative for many years in East Asia, yet its prescription has largely been based on empirical knowledge. In recent years, several new laxatives have been developed, which has led to a resurgence in interest and increased scientific evidence surrounding the use of magnesium oxide, which is convenient to administer, of low cost, and safe. Despite these advantages, emerging clinical evidence indicates that the use of magnesium oxide should take account of the most appropriate dose, the serum concentration, drug-drug interactions, and the potential for side effects, especially in the elderly and in patients with renal impairment. The aim of this review is to evaluate the evidence base for the clinical use of magnesium oxide for treating constipation and provide a pragmatic guide to its advantages and disadvantages.

Treatment Difficulties in Hypomagnesemia Secondary to the Transient Receptor Potential Melastatin 6 Gene: A Case Report with Novel Mutation

Hypomagnesemia is a rare cause of seizures in childhood but should be kept in mind in recurrent and intractable seizures and hypocalcemia in communities where consanguineous marriages are common. Familial hypomagnesemia with secondary hypocalcemia is a rare genetic cause of hypomagnesemia, due to variants in the transient receptor potential melastatin 6 (TRPM6) genes. Here, a three year-old boy with a novel variant in this gene and had difficulties with enteral hypomagnesemia treatment is presented. He had recurrent seizures since two years of age and was diagnosed with epilepsy and treated with multiple antiepileptic drugs. Subsequently, he was diagnosed with rickets due to severe hypocalcemia at another center. The patient was hypotonic and neurodevelopmentally poor. The most prominent laboratory finding was of hypomagnesemia with secondary hypocalcemia. The genetic analysis revealed a novel variant in the TRPM6 gene. After parental treatment of intravenous magnesium (Mg2+) sulfate and calcium, the treatment was switched to enteral Mg2+ medications, due to persistent hypomagnesemia and the gastrointestinal side-effects, different oral preparations were used. The patient was stable on an oral maintenance dose of Mg2+ oxide with borderline blood Mg2+ levels and resolution of hypocalcemia. Hypomagnesemia is one of the causes of hypocalcemia. Enteral replacement is the key treatment but the treatment should be individualized for each patient. Normalization of hypomagnesemia is not always easy and should not be the aim of the treatment.

Role of MgO nanoparticles in the suppression of Meloidogyne incognita, infecting cowpea and improvement in plant growth and physiology.

Root-knot disease, caused by Meloidogyne spp., alters histology as well as physiology of the roots thus influencing metabolism of vegetative and reproductive parts leading to huge losses in crop productivity. The experimental plant, Vigna unguiculata L. (cowpea of Fabaceae family) var. Gomti is an economically important pulse crop plant. An experiment was conducted to evaluate the effects of different concentrations (0, 25, 50 or 100 ppm) and various modes of applications (root dip, soil drench or foliar spray) of MgO nanoparticles on cowpea infected with M. incognita. The MgO nanoparticles were synthesized chemically and characterized by transmission and scanning electron microscopy (TEM, SEM), UV-Vis spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The scanning electron microscopy images of second stage juveniles of M. incognita treated with MgO nanoparticles (50 and 100 ppm) exhibited indentations, roughness and distortions in the cuticular surface, in comparison to the control untreated juveniles. MgO nanoparticles, in varying concentrations (50, 100 and 200 ppm), were dispensed into the plants by root dip, soil drench and foliar spray methods and their efficacy was assessed in terms of morphological characteristics, yield parameters and biochemical attributes of M. incognita infected plants. In planta trials revealed that 100 ppm dose of MgO nanoparticles, as root dip application, demonstrated reduced nematode fecundity, decreased number and smaller size of galls; enhanced plant growth, increased chlorophyll, carotenoid, seed protein, and root and shoot nitrogen contents. From these findings it could be inferred that MgO nanoparticles played twin roles, first as a nematicidal agent and the other as growth promotion inducer.

Appropriate usage of food thickening agents to prevent non-disintegration of magnesium oxide tablets.

Food thickening agents are used to aid the administration of medicine to elderly patients with dysphagia. Magnesium oxide tablets are sometimes administered with food thickening agents. Non-disintegration and disintegration delay of these tablets in the body are problems associated with food thickening agent use. However, the appropriate usage of food thickening agents for administering tablets is not established. Here, the reasons for the non-disintegration of magnesium oxide tablets administered with food thickeners and appropriate usage of food thickeners were examined using a disintegration test of newly opened and moisture-absorbed magnesium oxide tablets. Immersion of magnesium oxide tablets for 10 and 30 min in xanthan and guar gum-based food thickening agents caused disintegration delay and non-disintegration in the first fluid (pH 1.2). However, tablets immersed for 1 min quickly disintegrated. The disintegration of xanthan gum-based food thickening agents was faster than guar gum-based food thickening agents. Moisture absorption by magnesium oxide tablets caused a significant delay in their disintegration in water. The tablets that absorbed moisture disintegrated within 1 min in the first fluid, even when immersed in food thickening agents for a short time. Overall, a short immersion of magnesium oxide tablets in food thickening agents can avoid non-disintegration.

Nutritional interventions for treating foot ulcers in people with diabetes.

BACKGROUND: Foot ulcers in people with diabetes are non-healing, or poorly healing, partial, or full-thickness wounds below the ankle. These ulcers are common, expensive to manage and cause significant morbidity and mortality. The presence of a wound has an impact on nutritional status because of the metabolic cost of repairing tissue damage, in addition to the nutrient losses via wound fluid. Nutritional interventions may improve wound healing of foot ulcers in people with diabetes. OBJECTIVES: To evaluate the effects of nutritional interventions on the healing of foot ulcers in people with diabetes. SEARCH METHODS: In March 2020 we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that evaluated the effect of nutritional interventions on the healing of foot ulcers in people with diabetes. DATA COLLECTION AND ANALYSIS: Two review authors, working independently, assessed included RCTs for their risk of bias and rated the certainty of evidence using GRADE methodology, using pre-determined inclusion and quality criteria. MAIN RESULTS: We identified nine RCTs (629 participants). Studies explored oral nutritional interventions as follows: a protein (20 g protein per 200 mL bottle), 1 kcal/mL ready-to-drink, nutritional supplement with added vitamins, minerals and trace elements; arginine, glutamine and ß-hydroxy-ß-methylbutyrate supplement; 220 mg zinc sulphate supplements; 250 mg magnesium oxide supplements; 1000 mg/day omega-3 fatty acid from flaxseed oil; 150,000 IU of vitamin D, versus 300,000 IU of vitamin D; 250 mg magnesium oxide plus 400 IU vitamin E and 50,000 IU vitamin D supplements. The comparator in eight studies was placebo, and in one study a different dose of vitamin D. Eight studies reported the primary outcome measure of ulcer healing; only two studies reported a measure of complete healing. Six further studies reported measures of change in ulcer dimension, these studies reported only individual parameters of ulcer dimensions (i.e. length, width and depth) and not change in ulcer volume. All of the evidence identified was very low certainty. We downgraded it for risks of bias, indirectness and imprecision. It is uncertain whether oral nutritional supplement with 20 g protein per 200 mL bottle, 1 kcal/mL, nutritional supplement with added vitamins, minerals and trace elements, increases the proportion of ulcers healed at six months more than placebo (risk ratio (RR) 0.80, 95% confidence interval (CI) 0.42 to 1.53). It is also uncertain whether arginine, glutamine and ß-hydroxy-ß-methylbutyrate supplement increases the proportion of ulcers healed at 16 weeks compared with placebo (RR 1.09, 95% CI 0.85 to 1.40). It is uncertain whether the following interventions change parameters of ulcer dimensions over time when compared with placebo; 220 mg zinc sulphate supplement containing 50 mg elemental zinc, 250 mg magnesium oxide supplement, 1000 mg/day omega-3 fatty acid from flaxseed oil supplement, magnesium and vitamin E co-supplementation and vitamin D supplementation. It is also uncertain whether 150,000 IU of vitamin D, impacts ulcer dimensions when compared with 300,000 IU of vitamin D. Two studies explored some of the secondary outcomes of interest for this review. It is uncertain whether oral nutritional supplement with 20 g protein per 200 mL bottle, 1 kcal/mL, nutritional supplement with added vitamins, minerals and trace elements, reduces the number of deaths (RR 0.96, 95% CI 0.06 to 14.60) or amputations (RR 4.82, 95% CI 0.24 to 95.88) more than placebo. It is uncertain whether arginine, glutamine and ß-hydroxy-ß-methylbutyrate supplement increases health-related quality of life at 16 weeks more than placebo (MD -0.03, 95% CI -0.09 to 0.03). It is also uncertain whether arginine, glutamine and ß-hydroxy-ß-methylbutyrate supplement reduces the numbers of new ulcers (RR 1.04, 95% CI 0.71 to 1.51), or amputations (RR 0.66, 95% CI 0.16 to 2.69) more than placebo. None of the included studies reported the secondary outcomes cost of intervention, acceptability of the intervention (or satisfaction) with respect to patient comfort, length of patient hospital stay, surgical interventions, or osteomyelitis incidence. One study exploring the impact of arginine, glutamine and ß-hydroxy-ß-methylbutyrate supplement versus placebo did not report on any relevant outcomes. AUTHORS' CONCLUSIONS: Evidence for the impact of nutritional interventions on the healing of foot ulcers in people with diabetes compared with no nutritional supplementation, or compared with a different dose of nutritional supplementation, remains uncertain, with eight studies showing no clear benefit or harm. It is also uncertain whether there is a difference in rates of adverse events, amputation rate, development of new foot ulcers, or quality of life, between nutritional interventions and placebo. More research is needed to clarify the impact of nutritional interventions on the healing of foot ulcers in people with diabetes.

Magnesium Sulfate-Rich Natural Mineral Waters in the Treatment of Functional Constipation-A Review.

Functional constipation (FC) is a chronic constipation for which no physiological, anatomical or iatrogenic origin can be evidenced. This condition has a high impact on a patient's quality of life and healthcare costs. Since FC is frequently associated with low physical activity and a diet low in fiber and/or water, first-line recommendations focus on sufficient activity, and sufficient fiber and water intake. In case of inefficacy of these measures, numerous drug treatments are available, either over the counter or on prescription. Magnesium sulfate has a long history in the treatment of FC, and magnesium sulfate-rich mineral waters have been used for centuries for their laxative properties. The laxative effect of magnesium and sulfate has since been widely demonstrated. Nevertheless, it appears that no clinical studies aiming at demonstrating their efficacy in FC had been conducted before the 21st century. In this paper, we reviewed the clinical data reporting the efficacy of magnesium sulfate-rich natural mineral waters. In view of their reported efficacy and safety, magnesium sulfate-rich natural mineral waters may represent a natural treatment for FC.

Comparing the effectiveness of magnesium oxide and naldemedine in preventing opioid-induced constipation: a proof of concept, single institutional, two arm, open-label, phase II, randomized controlled trial: the MAGNET study.

BACKGROUND: Patients taking opioids are known to develop opioid-induced constipation (OIC), which reduces their quality of life. The aim of this study is to compare magnesium oxide with naldemedine and determine which is more effective in preventing OIC. METHODS: This proof-of-concept, prospective, randomized controlled trial commenced in Japan in March 2018. Initially, a questionnaire-based survey will be conducted targeting adult patients with cancer who concomitantly commenced opioid treatment and OIC prevention treatment. Patients will then be randomly allocated to a magnesium oxide group (500 mg thrice daily) or a naldemedine group (0.2 mg once daily). Each drug will be orally administered for 12 weeks. The primary endpoint is defined as any improvement in scores on the Japanese version of Patient Assessment of Constipation Quality of Life questionnaire (JPAC-QOL) from baseline to 2 weeks of treatment. DISCUSSION: The primary endpoint is change in JPAC-QOL score from baseline to 2 weeks of intervention. The key secondary endpoint will be change in spontaneous bowel movements at 2 and 12 weeks of intervention. This study will determine whether magnesium oxide or naldemedine is more effective for the prevention of OIC. TRIAL REGISTRATION: University Hospital Medical Information Network (UMIN) Clinical Trials Registry, UMIN000031891. Registered March 25, 2018.

Effect of Magnesium Supplementation on Circulating Biomarkers of Cardiovascular Disease.

(1) Background: Magnesium supplementation may be effective for the prevention of cardiometabolic diseases, but the mechanisms are unclear. Proteomic approaches can assist in identifying the underlying mechanisms. (2) Methods: We collected repeated blood samples from 52 individuals enrolled in a double-blind trial which randomized participants 1:1 to oral magnesium supplementation (400 mg magnesium/day in the form of magnesium oxide) or a matching placebo for 10 weeks. Plasma levels of 91 proteins were measured at baseline with follow-up samples using the Olink Cardiovascular Disease III proximity extension assay panel and were modeled as arbitrary units in a log2 scale. We evaluated the effect of oral magnesium supplementation for changes in protein levels and the baseline association between serum magnesium and protein levels. The Holm procedure was used to adjust for multiple comparisons. (3) Results: Participants were 73% women, 94% white, and had a mean age of 62. Changes in proteins did not significantly differ between the two intervention groups after correction for multiple comparisons. The most statistically significant effects were on myoglobin [difference -0.319 log2 units, 95% confidence interval (CI) (-0.550, -0.088), p = 0.008], tartrate-resistant acid phosphatase type 5 (-0.187, (-0.328, -0.045), p = 0.011), tumor necrosis factor ligand superfamily member 13B (-0.181, (-0.332, -0.031), p = 0.019), ST2 protein (-0.198, (-0.363, -0.032), p = 0.020), and interleukin-1 receptor type 1 (-0.144, (-0.273, -0.015), p = 0.029). Similarly, none of the associations of baseline serum magnesium with protein levels were significant after correction for multiple comparisons. (4) Conclusions: Although we did not identify statistically significant effects of oral magnesium supplementation in this relatively small study, this study demonstrates the value of proteomic approaches for the investigation of mechanisms underlying the beneficial effects of magnesium supplementation. Clinical Trials Registration: ClinicalTrials.gov NCT02837328.

Antifungal Activity of Magnesium Oxide Nanoparticles: Effect on the Growth and Key Virulence Factors of Candida albicans.

The aim of this research was to study the effects of different concentrations of magnesium oxide nanoparticles (MgO NPs) on the growth and key virulence factors of Candida albicans (C. albicans). The minimum inhibitory concentration (MIC) of MgO NPs against C. albicans was determined by the micro-broth dilution method. A time-kill curve of MgO NPs and C. albicans was established to investigate the ageing effect of MgO NPs on C. albicans. Crystal violet staining, the MTT assay, and inverted fluorescence microscopy were employed to determine the effects of MgO NPs on C. albicans adhesion, two-phase morphological transformation, biofilm biomass, and metabolic activity. The time-kill curve showed that MgO NPs had fungicidal and antifungal activity against C. albicans in a time- and concentration-dependent manner. Semi-quantitative crystal violet staining and MTT assays showed that MgO NPs significantly inhibited C. albicans biofilm formation and metabolic activity, and the difference was statistically significant (p < 0.001). Inverted fluorescence microscopy showed that MgO NPs could inhibit the formation of C. albicans biofilm hyphae. Adhesion experiments showed that MgO NPs significantly inhibited the initial adhesion of C. albicans (p < 0.001). This study demonstrates that MgO NPs can effectively inhibit the growth, initial adhesion, two-phase morphological transformation, and biofilm formation of C. albicans and is an antifungal candidate.

Multifunctional nanocomposites MGO/FU-MI inhibit the proliferation of tumor cells and enhance the effect of chemoradiotherapy in vivo and in vitro.

PURPOSE: The limitation of surgery, radiotherapy and chemotherapy in the treatment of cancer and the rise of the application of nanomaterials in the field of biomedicine have promoted the application of various nanomaterials in the combination of radiotherapy and chemotherapy in the treatment of cancer. To improve the efficiency of cancer treatment, the multifunctional nanocomposites MGO/FU-MI (MGO/FU-MI NCs) were used for combination chemotherapy and radiotherapy to verify its effectiveness in treating tumors. METHODS: The proliferation activity of MGO/FU-MI NCs on MC-38 and B16 cells was detected by CCK-8, and the level of apoptosis and reactive oxygen species were detected by flow cytometry. To verify its efficacy in the combination of chemoradiotherapy, different treatment regimens were developed for several groups of tumor-bearing mice. RESULTS: The MGO/FU-MI NCs can induce apoptosis, stimulate ROS production, and inhibit cell proliferation. In vivo experiments, when MGO/FU-MI NCs are used alone for chemotherapy, have a certain therapeutic effect on mouse tumors. When MGO/FU-MI NCs are combined with radiation, the tumor volume can be significantly reduced and the survival time of mice is significantly prolonged. CONCLUSION: The MGO/FU-MI NCs are very effective in the treatment of tumors when combined with radiotherapy and chemotherapy, and have the potential to be a combination of radiotherapy and chemotherapy.

Management of an i.v. fluid shortage through use of electronic medical record alerts.

PURPOSE: Evaluation of mechanisms used to cope with an i.v. fluid shortage to determine if prescribing habits were changed and if substitution of an i.v. dose of magnesium with an oral dose impacted patient outcomes. METHODS: A single-center, retrospective analysis of electronic medical record (EMR) alerts and medical records covering 6-month periods before and during an i.v. fluid shortage was conducted. Records of adult medical and surgical inpatients admitted during these periods who had an order for i.v. or oral magnesium were screened for inclusion. The primary outcome of part 1 of the study was the percent acceptance of drug shortage-related EMR alert recommendations associated with i.v. magnesium. The primary outcome of part 2 of the study was the change in serum magnesium concentration (SMC) after an i.v. or oral dose of magnesium was administered. RESULTS: Of the 7,476 EMR alerts generated during provider ordering of i.v. magnesium products, 4.8% resulted in the provider accepting the recommendation to switch to an oral alternative, 89% resulted in continuation of an i.v. magnesium order, and 6.2% resulted in order cancellation. Among patients who received magnesium doses, SMC values increased by a mean (SD) of 0.135 (0.08) mg/dL per gram of i.v. magnesium sulfate administered (n = 251), compared to an increase of 0.058 (0.08) mg/dL per 400-mg tablet of magnesium oxide administered (n = 42). CONCLUSION: Acceptance of the EMR alert recommendations was low. Both i.v. magnesium sulfate and oral magnesium oxide are viable options for increasing SMC.

Effects of calcium carbonate, magnesium oxide and encapsulated sodium bicarbonate on measures of post-ruminal fermentation.

Evidence suggests that lipopolysaccharide (LPS) absorbed from the large intestine may contribute to the inflammatory response to high starch feeding in dairy cows. This work evaluated the impact of buffers or alkalinizing agents with expected large intestinal activity on faecal indicators of intestinal fermentation and LPS. Ten late-lactation cows were used in a replicated 5 × 5 Latin square design with 7-day periods. Cows were fed a diet containing 265 g/kg dry matter of starch and were abomasally infused with 1 g/kg body weight cornstarch daily. Treatments were control (CON), ration supplementation with 200 g/day sodium bicarbonate (FSB), 200 g/day calcium carbonate (FCC) or 125 g/day calcium carbonate plus 75 g/day of magnesium oxide (FCCM), or abomasal infusion of a lipid encapsulate providing 200 g/day sodium bicarbonate (ISB). The FCC, FCCM and ISB treatments were hypothesized to have large intestinal buffering effects, and FSB was included as a secondary control. Milk, feed, rumen and faecal samples were collected on day 7 of each period. Treatment did not affect intake, milk yield or milk composition. There were no effects of treatment on ruminal measures except that ISB tended to reduce and the post-ruminal treatments as a whole (FCC, FCCM and ISB) reduced rumen butyrate compared with CON. Faecal pH was greater for FCCM compared with all other treatments. Total faecal VFA tended to increase with FCC and FCCM compared with CON and was increased by the post-ruminal treatments as a whole compared with CON. Treatment did not affect faecal dry matter, lactate or LPS or apparent total tract nutrient digestibility. Although some treatments altered fermentation as evidenced by the change in faecal VFA, this was not accompanied by a decrease in faecal LPS. The strategies employed in this study had limited effects on large intestinal fermentation.

Circulating Ionized Magnesium: Comparisons with Circulating Total Magnesium and the Response to Magnesium Supplementation in a Randomized Controlled Trial.

Ionized Mg (iMg) is considered the biologically active fraction of circulating total Mg (tMg). It is possible that iMg may be a more physiologically relevant marker than tMg. Using data from a double-blind pilot randomized controlled trial, we tested (1) whether oral Mg supplementation will increase iMg concentrations compared with placebo and (2) the relationship between iMg and tMg at baseline. Additionally, we evaluated the agreement between iMg measured in fresh whole blood versus stored samples. A total of fifty-nine participants were randomized 1:1 to oral Mg supplementation (400 mg/day, Mg Oxide) or placebo for 10 weeks. Fasting blood samples were obtained at baseline and follow-up. The analysis used linear regression and an intent-to-treat approach. Participants were generally healthy, the mean age was 62, and 73% were female. The baseline iMg and tMg were modestly and positively associated (r = 0.50). The ratio of baseline iMg to tMg was 64%. The mean supplement effect on iMg was 0.03 mmol/L (95% CI:0.01, 0.05) for Mg supplementation versus placebo. The supplement effect on iMg was not statistically significantly different according to baseline iMg status (above/below median). Compared to fresh blood, iMg was consistently higher in refrigerated and frozen samples by 0.14 and 0.20 mmol/L, respectively. In this relatively healthy adult population, Mg supplementation over 10 weeks resulted in increased iMg concentrations. Whether iMg is a more appropriate measure of Mg status than tMg, and the public health or clinical utility of measuring iMg remains to be determined.

Oral Magnesium Supplementation Improved Lipid Profile but Increased Insulin Resistance in Patients with Diabetic Nephropathy: a Double-Blind Randomized Controlled Clinical Trial.

Low serum magnesium concentrations were associated with development of renal failure. We aimed to determine whether magnesium supplementation improves renal function, insulin resistance, and metabolic profiles in patients with diabetic nephropathy. A total of 80 hypomagnesemic patients diagnosed with type 2 diabetes and early-stage nephropathy were recruited. Subjects received either daily magnesium oxide or placebo for 12 weeks. Biochemical and anthropometric variables were measured. Physical activity and dietary intakes were also recorded. This study was approved by the ethics committee of Isfahan University of Medical Sciences and was registered on the Iranian Registry of Clinical Trials website (IRCT registration no. IRCT201404271485N12). Serum magnesium levels were not changed significantly. Although the supplementation did not influence glycemic indices, patients in the magnesium group had greater insulin resistance compared with the placebo group after intervention (0.3 ± 2.3 µIU/mL vs. - 0.04 ± 2.05, P = 0.04). No significant changes were observed in serum total cholesterol, triglycerides, HDL, LDL, and total cholesterol/HDL cholesterol ratio. Furthermore, magnesium did not affect inflammation, serum levels of creatinine, and blood urine nitrogen. However, a marginal decrease in microalbuminuria (- 3.1 ± 2.2 mg/L vs. - 14 ± 9.9, P = 0.09) was observed. Oral magnesium supplementation slightly improved microalbuminuria but resulted in increased insulin resistance in patients with diabetic nephropathy.

Magnesium Bioavailability and Tolerability Do Not Differ between Two Supplements with Different Release Properties.

Magnesium (Mg2+) is one of the most frequently supplemented micronutrients. Due to possible gastrointestinal side effects, the European Food Safety Authority and the Institute of Medicine set the upper intake level for Mg2+ from supplements to 250 and 350 mg, respectively. Nevertheless, systematic data concerning the tolerability of Mg2+ supplements are scarce. The aim of the study was to directly compare the bioavailability and tolerability of two 500 mg Mg2+ supplements in a crossover study with duplicate determination. The different release properties were either a direct release (one phase) or a delayed release of the second half (two phases). An open-label, controlled trial with a crossover design, duplicate determination, and one-week washout phases was conducted. The participants ingested the test product after overnight fasting. Blood samples were taken at baseline and after 1, 2, 3, 4, 6, and 8 hours, and urine was collected over a period of 24 hours. The participants were on standardized nutrition during all examination days. There were no significant differences between the test products regarding 24-hour renal Mg2+ excretion and area under the curve of serum Mg2+ levels for 8 hours. Both test products were well tolerated with a very low frequency of gastrointestinal adverse effects and no significant differences between the test products. The Mg2+ bioavailability did not differ between the test products. The supplements examined had the same good tolerability. Both test products are therefore suited to enhance Mg2+ supply without relevant side effects.

The effect of calcareous marine algae, with or without marine magnesium oxide, and sodium bicarbonate on rumen pH and milk production in mid-lactation dairy cows.

Two experiments were carried out to evaluate different dietary buffers and their influence on (1) rumen pH in dairy cows and (2) milk production in dairy cows. The supplements included were calcareous marine algae (CMA; Lithothamnion calcareum), with or without marine magnesium oxide (MM; precipitated magnesia derived from seawater), and sodium bicarbonate (SB). Dietary treatments in experiment 1 consisted of the control [32.9% starch and sugar, and 19.9% neutral detergent fiber from forage per kg of dry matter (DM)] including no dietary buffer (CON); the control plus 0.45% DM CMA (CMA); the control plus 0.45% DM CMA and 0.11% DM MM (CMA+MM); the control plus 0.9% DM SB (SB). Diets were formulated to a dry matter intake (DMI) of 18 kg per cow/d. Dietary treatments in experiment 2 also consisted of CON (28.3% starch and sugar, and 23% neutral detergent fiber from forage per kg of DM), CMA, CMA+MM, and SB and were formulated to achieve identical intakes of experimental ingredients (80 g of CMA, 80 g of CMA plus 20 g MM, and 160 g of SB per cow/d) with a DMI of 22.6 kg per cow/d. Experiment 1 used 4 rumen-cannulated dairy cows in a 4 × 4 Latin square design. Rumen pH was measured over five 2-h periods, following feeding, using rumen pH probes. In experiment 2, 52 multiparous and 4 primiparous cows (62.7 ± 3.4 d in milk) were assigned to 4 experimental treatments for 80 d. Both CMA treatments maintained a greater mean rumen pH than the CON during 4 of the 5 periods following feeding and the CON had a greater number of hours below rumen pH 5.5 compared with all other treatments. Dry matter intakes tended to be higher on the SB compared with CON. The CMA treatment increased the production of milk fat and protein yield (kg/d) compared with all other treatments. Both CMA and CMA+MM increased milk fat yield compared with CON but were similar to each other and SB. Protein yield was highest in the CMA treatment compared with CON, CMA+MM, and SB. All 3 buffer treatments increased milk fat concentration compared with CON but did not differ from each other. The SB treatment reduced milk protein concentration and milk production efficiency, energy-corrected milk per kilogram of DMI. Results indicate that the addition of CMA can benefit milk fat and protein production when included in diets based on typical feedstuffs of the northern European region. The use of CMA when compared with SB, in such diets, can increase milk protein production and milk production efficiency.

Effects of magnesium citrate, magnesium oxide and magnesium sulfate supplementation on arterial stiffness in healthy overweight individuals: a study protocol for a randomized controlled trial.

BACKGROUND: Arterial stiffness is closely related to the process of atherosclerosis, an independent cardiovascular risk factor, and predictive of future cardiovascular events and mortality. Recently, we showed that magnesium citrate supplementation results in a clinically relevant improvement of arterial stiffness. It remained unclear whether the observed effect was due to magnesium or citrate, and whether other magnesium compounds may have similar effects. Therefore, we aim to study the long-term effects of magnesium citrate, magnesium oxide and magnesium sulfate on arterial stiffness. In addition, we aim to investigate possible underlying mechanisms, including changes in blood pressure and changes in gut microbiota diversity. METHODS: In this randomized, double-blind, placebo-controlled trial, a total of 162 healthy overweight and slightly obese men and women will be recruited. During a 24-week intervention, individuals will be randomized to receive: magnesium citrate; magnesium oxide; magnesium sulfate (total daily dose of magnesium for each active treatment 450 mg); or placebo. The primary outcome of the study is arterial stiffness measured by the carotid-femoral pulse wave velocity (PWVc-f), which is the gold standard for quantifying arterial stiffness. Secondary outcomes are office blood pressure, measured by a continuous blood pressure monitoring device, and gut microbiota, measured in fecal samples. Measurements will be performed at baseline and at weeks 2, 12 and 24. DISCUSSION: The present study is expected to provide evidence for the effects of different available magnesium formulations (organic and inorganic) on well-established cardiovascular risk markers, including arterial stiffness and blood pressure, as well as on the human gut microbiota. As such, the study may contribute to the primary prevention of cardiovascular disease in slightly obese, but otherwise healthy, individuals. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03632590 . Retrospectively registered on 15 August 2018.

A Randomized Trial of Magnesium Oxide and Oral Carbon Adsorbent for Coronary Artery Calcification in Predialysis CKD.

BACKGROUND: Developing strategies for managing coronary artery calcification (CAC) in patients with CKD is an important clinical challenge. Experimental studies have demonstrated that magnesium inhibits vascular calcification, whereas the uremic toxin indoxyl sulfate aggravates it. METHODS: To assess the efficacy of magnesium oxide (MgO) and/or the oral carbon adsorbent AST-120 for slowing CAC progression in CKD, we conducted a 2-year, open-label, randomized, controlled trial, enrolling patients with stage 3-4 CKD with risk factors for CAC (diabetes mellitus, history of cardiovascular disease, high LDL cholesterol, or smoking). Using a two-by-two factorial design, we randomly assigned patients to an MgO group or a control group, and to an AST-120 group or a control group. The primary outcome was percentage change in CAC score. RESULTS: We terminated the study prematurely after an interim analysis with the first 125 enrolled patients (of whom 96 completed the study) showed that the median change in CAC score was significantly smaller for MgO versus control (11.3% versus 39.5%). The proportion of patients with an annualized percentage change in CAC score of ≥15% was also significantly lower for MgO compared with control (23.9% versus 62.0%). However, MgO did not suppress the progression of thoracic aorta calcification. The MgO group's dropout rate was higher than that of the control group (27% versus 17%), primarily due to diarrhea. The percentage change in CAC score did not differ significantly between the AST-120 and control groups. CONCLUSIONS: MgO, but not AST-120, appears to be effective in slowing CAC progression. Larger-scale trials are warranted to confirm these findings.