In this report, we present a pediatric case of severe symptomatic hypermagnesemia resulting from the use of magnesium oxide as a laxative in a child undergoing continuous cyclic peritoneal dialysis for end-stage renal disease. The patient showed abnormal electrocardiography (ECG) findings, such as tall T waves, a widened QRS complex, and irregular conduction, which were initially misdiagnosed as hyperkalemia; later, the correct diagnosis of hypermagnesemia was obtained. Emergent hemodialysis successfully returned the serum magnesium concentration to normal without complications. When abnormal ECG changes are detected in patients with renal failure, hypermagnesemia should be considered.
Child ; Electrocardiography ; Humans ; Hyperkalemia ; Kidney Failure, Chronic ; Magnesium ; Magnesium Oxide ; Peritoneal Dialysis ; Renal Dialysis ; Renal Insufficiency

We investigated the comparative effect of magnesium and thiosulfate on the calcium oxalate crystallization. Magnesium is a strong inhibitor of calcium oxalate crystallization and it is sported to inhibit calcium phophate by about 20%. Even if it's mechanism is not clearly known, thiosulfat can resolve 250~100,000 times more than other calcium salts when it is combined with calcium. Wistar rats were fed by 1.0% ethylene glycol (EG) mixed with water. 500mg of magnesium oxide (MgO) per 100gm chows and 10mMo1 of S2O3 per 100gm chows were provided by oral intake respectively. Forty eight wistar rats were divided into following 6 groups. Each group has equal 8 wistar rats; A group (normal chow and water), B group (normal chow and 1%EG), C group (MgO and 1%EG), D group (MgO and water), E group (S2O3 and 1%EG), and F group (S2O3 and water). First, we examined calcium oxalate crystallization on bladder aspiration urine for 6 groups before the experiment and every week for 4 weeks after the experiment. Second, we also examined the degree of formation of calcium oxalate crystallization in renal tissue under polarizing microscope. Calcium oxalate crystallization was found in all 8 wistar rats in B group while it was not round in A, D, F group. Calcium oxalate crystallization was also found in one out of 8 wistar rats in C group, and 5 out of 8 wistar rats in E group. In conclusion, we believe that both MgO and sodium thiosulfate are effective in preventing calcium oxalate stone, and we also believe MgO is more elective than sodium thiosulfate. We think that further researches on administrating methods, the side effects and dosage of these two agents in human are necessary.
Calcium Oxalate* ; Calcium* ; Crystallization* ; Ethylene Glycol ; Humans ; Magnesium Oxide* ; Magnesium* ; Nephrolithiasis ; Rats, Wistar ; Salts ; Sodium* ; Sports ; Urinary Bladder ; Water

BACKGROUND/AIMS: Magnesium oxide (MgO) has been frequently used as a treatment for chronic constipation (CC) since the 1980s in Japan. The aim of this study is to evaluate its therapeutic effects of MgO in Japanese CC patients. METHODS: We conducted a randomized, double-blind placebo-controlled study. Thirty-four female patients with mild to moderate constipation were randomly assigned to either placebo (n = 17) or MgO group (n = 17) 0.5 g × 3/day for 28 days. Primary endpoint was overall improvement over the 4-week study period. Secondary endpoints were changes from baseline in spontaneous bowel movement (SBM), response rates of complete spontaneous bowel movement (CSBM), stool form, colonic transit time (CTT), abdominal symptom, and quality of life. RESULTS: One patient failed to complete the medication regimen and was omitted from analysis: data from 16 placebo and 17 MgO patients were analyzed. The primary endpoint was met by 25.0% of placebo vs 70.6% of MgO group (P = 0.015). MgO significantly improved SBM changes compared to placebo (P = 0.002). However, MgO did not significantly improved response rates of CSBM compared to placebo (P = 0.76). In addition, MgO significantly improved Bristol stool form scale changes (P < 0.001) and significantly improved CTT compared to the placebo group (P < 0.001). MgO significantly improved the Japanese version of the patient assessment of constipation quality of life (P = 0.003). CONCLUSION: Our placebo-controlled study demonstrated that MgO was effective treatment for improving defecation status and shortened CTT in Japanese CC patients with mild to moderate symptoms.
Asian Continental Ancestry Group ; Colon ; Constipation ; Defecation ; Double-Blind Method ; Female ; Humans ; Japan ; Magnesium Oxide ; Magnesium ; Quality of Life ; Therapeutic Uses

BACKGROUND/AIMS: Polyethylene glycol (PEG) electrolyte lavage solution is now commonly used for peroral colonic preparation. However, the need to ingest a large volume reduces patient acceptance and may limit compliance, thereby resulting in improper preparation. This study was designed to assess whether adding of magnesium oxide or cisapride to PEG solution decreased the volume of PEG solution required without compromising the quality of the preparation. METHODS: One hundred thirty seven patients undergoing outpatient colonoscopy were randomly chosen to receive one of three preparations (Group A: 4 L PEG; Group B: 2 L PEG plus cisapride 20 mg; Group C: 2 L PEG plus magnesium oxide 2 g). Endoscopist was blinded as to the method of preparation and scored the degree of colonic preparation (1 to 4). RESULTS: Mean scores of preparation in group A, B, and C were 2.85, 2.69, and 2.20, respectively (p=0.001). There were significant differences of the degree of preparation between group A and group C, between group B and group C, but not between group A and group B. CONCLUSIONS: Two liters of PEG plus cisapride induced equally effective colonic preparation compared to four liter PEG solution. This results show that the addition of cisapride to PEG solution can reduce volume of PEG solution during colonoscopy preparation.
Cisapride* ; Colon ; Colonoscopy* ; Compliance ; Humans ; Magnesium Oxide ; Outpatients ; Polyethylene Glycols ; Therapeutic Irrigation*

A 66 year-old male patient underwent resection of a pheochromocytoma under general anesthesia. The patient was treated with phenoxybenzamine and propranolol for 7 days preoperatively. Follwing an induction of anesthesia with intravenous fentanly 100 ug, thiopental sodium 250 mg, vecuronium 12 mg, and magnesium sulfate 3.0 gm, endotracheal intubation was performed. Aneathesia was maintained with nitrous oxide, oxygen and isoflurane. For the management of blood pressure during surgical manipulation, magnesium sulfate was infused at the rate of 0.75-1.0 mg/kg/min. After the removal of the tumor mass, the blood pressure dropped to 80/40 mmHg. Whole blood and fresh frozen plasma were transfused and norepinephrine 0.5 ug/kg was infused to maintain the blood pressure for 40 min. Postanesthestic recovery course was uneventful.
Aged ; Anesthesia ; Anesthesia, General ; Anesthetics ; Blood Pressure ; Humans ; Intubation, Intratracheal ; Isoflurane ; Magnesium Sulfate* ; Magnesium* ; Male ; Nitrous Oxide ; Norepinephrine ; Oxygen ; Phenoxybenzamine ; Pheochromocytoma* ; Plasma ; Propranolol ; Thiopental ; Vecuronium Bromide

STATEMENT OF PROBLEM: Magnesium oxide may increase pH of alginate, and supply magnesium ions to the polymerization reaction of alginate. PURPOSE: This study was designed to evaluate the influence of incorporation of magnesium oxide to alginate composition. MATERIAL AND METHOD: Seven kinds of experimental alginates were prepared and used for the experiments. Components with unchanging concentrations were sodium alginate 15%, calcium sulfate 14%, sodium phosphate 2%, and zinc fluoride 3%. Contents of magnesium oxide were varied as 0%, 1%, 2%, 3%, 4%, 5%, 6%. Diatomaceous earth were added to each experimental groups as balance to be 100%. Control group was a MgO 0% group. Working time, setting time, elastic recovery, strain in compression, compressive strength and tear resistance were measured were measured. Sample size for each groups were 10. Arithmetic means were used as each groups representative values. Regression test between MgO contents and results, Duncan's multiple range test, and One-way ANOVA test were done between groups at level of 0.05. RESULTS: 1. Magnesium oxide made the working time and setting time as longer(p<0.0001). 2. Magnesium oxide did not alter the elastic recovery(p>0.05). 3. Magnesium oxide contents between 2% and 4% exhibited the lowest strain in compression on alginates(p<0.0001). 4. Magnesium oxide made the compressive strength and the tear resistance stronger(p<0.0001). CONCLUSION: These results mean that setting time of alginate maybe controlled and that mechanical properties maybe improved by the incorporation of magnesium oxide into alginate, without any reduction of elasticity.
Alginates* ; Calcium Sulfate ; Compressive Strength ; Diatomaceous Earth ; Elasticity ; Fluorides ; Hydrogen-Ion Concentration ; Ions ; Magnesium Oxide* ; Magnesium* ; Polymerization ; Polymers ; Sample Size ; Sodium ; Tears ; Zinc

A 50-year-old woman was referred to our hospital for evaluation of mental change and general weakness accompanied by an irregular and weak pulse. She had previously been diagnosed with Bartter's syndrome and had taken potassium-sparing diuretics. She had developed constipation that had led to abdominal pain and had taken excessive magnesium oxide over a long time. On admission, she was lethargic. Her blood pressure (BP) was 130/74 mmHg, with a heart rate varying from 30 to 78 beats/min. An electrocardiogram (ECG) revealed several abnormalities, including first degree AV block, QT prolongation, sinus pause with a junctional rhythm, and paroxysmal tachycardia alternating with sinus pause. Her serum concentration of magnesium was markedly elevated to 16.19 mg/dl. Hemodialysis and a calcium gluconate infusion was attempted to reduce magnesium levels and to counteract the cardiovascular effect of magnesium. As magnesium levels declined, her general medical condition improved and her ECG changes were normalized. Severe hypermagnesemia should be suspected as the cause of mental change, cardiovascular dysfunction, and variable ECG changes.
Abdominal Pain ; Atrioventricular Block ; Bartter Syndrome ; Blood Pressure ; Calcium Gluconate ; Constipation ; Depression ; Diuretics ; Electrocardiography ; Female ; Gluconates ; Heart Rate ; Humans ; Magnesium ; Magnesium Oxide ; Middle Aged ; Renal Dialysis ; Tachycardia, Paroxysmal

Postganglionic cholinergic dysautonomia is a rare disease characterized by impaired secretion of tears and saliva, generalized absence of sweating, lack of cardiac response to carotid massage and atony of the gastrointestinal tract and urinary bladder. Autonomic function tests show the preservation of sympathetic adrenergic functions in contrast to the generalized involvement of postganglionic parasympathetic and sympathetic cholinergic nerves. Recently, we experienced a patient with gut dysmotility in selective postganglionic cholinergic dysautonomia. She is now being treated with bethanechol and milk of magnesia and has experienced minimal symptom improvement.
Bethanechol ; Gastrointestinal Tract ; Humans ; Magnesium Oxide ; Massage ; Milk ; Primary Dysautonomias* ; Rare Diseases ; Saliva ; Sweat ; Sweating ; Tears ; Urinary Bladder

OBJECTIVEThis study evaluated the wear of an antagonist and friction and wear properties of dental zirconia ceramic that was subjected to microwave and conventional sintering methods.

METHODSTen specimens were fabricated from Lava brand zirconia and randomly assigned to microwave and conventional sintering groups. A profile tester for surface roughness was used to measure roughness of the specimens. Wear test was performed, and steatite ceramic was used as antagonist. Friction coefficient curves were recorded, and wear volume were calculated. Finally, optical microscope was used to observe the surface morphology of zirconia and steatite ceramics. Field emission scanning electron microscopy was used to observe the microstructure of zirconia.

RESULTSWear volumes of microwave and conventionally sintered zirconia were (6.940±1.382)×10⁻², (7.952±1.815) ×10⁻² mm³, respectively. Moreover, wear volumes of antagonist after sintering by the considered methods were (14.189±4.745)×10⁻², (15.813±3.481)×10⁻² mm³, correspondingly. Statistically significant difference was not observed in the wear resistance of zirconia and wear volume of steatite ceramic upon exposure to two kinds of sintering methods. Optical microscopy showed that ploughed surfaces were apparent in zirconia. The wear surface of steatite ceramic against had craze, accompanied by plough. Scanning electron microscopy showed that zirconia was sintered compactly when subjected to both conventional sintering and microwave methods, whereas grains of zirconia sintered by microwave alone were smaller and more uniform.

CONCLUSIONSTwo kinds of sintering methods are successfully used to produce dental zirconia ceramics with similar friction and wear properties.
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Ceramics ; Dental Porcelain ; Friction ; Humans ; Magnesium Oxide ; Materials Testing ; Microscopy, Electron, Scanning ; Microwaves ; Silicon Dioxide ; Surface Properties ; Zirconium

Mg2Ni0.8Cr0.2-x wt.% CoO/Al2O3 (x=0.5, 1, 2 and 3) composites were prepared by mechanically milling sintered Mg2Ni0.8Cr0.2 alloy and CoO/Al2O3 compound for 45 h. The addition of CoO/Al2O3 compound resulted in the good kinetics properties of hydriding/dehydriding reaction of the composites. The composite with 1.0 wt.% CoO/Al2O3 catalyst could reach the maximum hydrogen absorption capacity (2.9 wt.%) within 5 min at 393 K under H2 pressure of 4 MPa, and can desorb rapidly at 493 K. The decomposition and synthesis of hydrogen molecule on Mg2Ni0.8Cr0.2 alloy surface was promoted by addition of CoO/Al2O3 catalyst. In addition, the formation of metallic Ni particles, strain and defects during the ball milling process also resulted in the improved hydrogenation performance of Mg2Ni-based alloys.
Absorption ; Aluminum Oxide ; analysis ; chemistry ; Hot Temperature ; Hydrogen ; analysis ; chemistry ; Kinetics ; Magnesium Compounds ; analysis ; chemistry ; Manufactured Materials ; analysis ; Materials Testing ; Molecular Conformation ; Nitrogen Compounds ; analysis ; chemistry ; Pressure ; Temperature