Different neutralizing agents were used as pH controller to investigate their effects on the growth and succinic acid production of Actinobacillus succinogenes NJ113. The fermentation results showed that Ca(OH)2, CaCO3 and NH4OH were not suitable for succinic acid production by A. succinogenes NJ113 because of their negative effects on cell growth. When Na-base was used, cells would flocculate and lump, and due to the sodium ion concentration reaching to a high level, OD660 dropped sharply after 12 h of fermentation. Mg-base was better because there was no significant inhibition by magnesium ion. Two combined neutralizing agents were used to maintain pH level, one with NaOH and Mg(OH)2 while the other with Na2CO3 and Mg(OH)2. The optimum ratios of the combined neutralizing agents were both 1:1 (g:g) when using 100 g/L glucose. When NaOH and Mg(OH)2 were chosen with the ratio of 1:1(g:g), 69.8 g/L of the succinic acid and 74.5% of the yield was obtained.
Actinobacillus ; genetics ; metabolism ; Fermentation ; Hydrogen-Ion Concentration ; Industrial Microbiology ; Magnesium Hydroxide ; pharmacology ; Sodium Hydroxide ; pharmacology ; Succinic Acid ; metabolism

No abstract available.
Administration, Oral ; *Colonoscopy ; Gastric Lavage/*methods ; Humans ; Magnesium Hydroxide/*administration &dosage ; Polyethylene Glycols/*administration &dosage

BACKGROUND/AIMS: This study was designed to compare the efficacy and patient tolerance between standard bowel preparation using 4 liters of polyethylene glycol (PEG) solution and 4 liters of PEG preceded by the osmotic laxative, magnesium hydroxide in constipation and non-constipation group. METHODS: 173 outpatient colonoscopy, except for three patients who were not taking magnesium, were divided into constipation and non-constipation group. Then, the patients were randomly assigned to receive 4-liter of PEG solution or 4-liter of PEG plus magnesium hydroxide. The quality of bowel preparation was assessed using Ottawa scale, and satisfaction score was assessed using questionnaires. Solid stool, cecal intubation time, compliance, and side effects were assessed. RESULTS: Non-constipation group showed no significant differences between two groups. In constipation group, 4-liter PEG solution plus magnesium hydroxide induced the more effective colonic preparation (Ottawa scale 2.47+/-0.99 vs. 5.92+/-2.39, p<0.05), and less solid stool (0.67+/-0.72 vs. 1.38+/-0.65, p<0.05) compared with 4-liter PEG solution. CONCLUSIONS: Bowel preparation with magnesium hydroxide and 4 liters of PEG solution might reduce solid stool in constipation group, but could not improve preparation quality.
Administration, Oral ; Adult ; Aged ; *Colonoscopy ; Female ; Gastric Lavage/*methods ; Humans ; Magnesium Hydroxide/*administration &dosage ; Male ; Middle Aged ; Polyethylene Glycols/*administration &dosage ; Questionnaires

The important factors involved in the regulation of PTH are calcium, vitamin D, and phosphorus. However, recent studies have suggested that magnesium may also play a significant role in the modulation of PTH. The aims of this study was to analyze the relationship between serum magnesium and PTH levels in the hemodialysis patients. We studied 66 stable patients under maintenance hemodialysis for more than 6 months. Calcium carbonate was used as a phosphate binder in all patients. No patient had been previously treated with vitamin D and aluminum hydroxide. Biochemical parameters were evaluated 3 times during 7 months, and the mean values were computed. The mean serum magnesium level was 2.7+/-0.4 mEq/L. Hypermagnesemia(defined as serum Mg>2.2 mEq/L) was found in 60 patients(90.1%). Serum magnesium levels were inversely correlated with serum iPTH levels(r=-0.579; p<0.001). Serum total and ionized calcium levels were inversely correlated with serum iPTH levels(r=-0.743; p<0.001, r=-0.699; p<0.001, respectively). Serum alkaline phosphatase levels positively correlated with serum iPTH levels (r=0.364; p=0.003). In lower iPTH group(serum iPTHmagnesium, total calcium, and ionized calcium levels were significantly higher. Alkaline phosphatase level was significantly lower in lower PTH group. After controlling for the effect of the other variables, serum magnesium and iPTH levels were inversely correlated(r=-0.53; p<0.001). A stepwise multiple regression analysis showed that serum magnesium level was the most predictive variable(R2=0.72; p<0.001). Hypermagnesemia is frequent in hemodialysis patients. There is a significant inverse relationship between serum magnesium and PTH levels. In addition, serum magnesium concentration has an important influence on PTH regulation. These results suggest that hypermagnesemia may have a suppressive effect on PTH regulation in hemodialysis patients.
Alkaline Phosphatase ; Aluminum Hydroxide ; Calcium ; Calcium Carbonate ; Humans ; Magnesium* ; Parathyroid Hormone* ; Phosphorus ; Receptors, Calcium-Sensing ; Renal Dialysis* ; Renal Osteodystrophy ; Vitamin D

PURPOSE: It has previously been reported that citrate, thiazide, allopurinol and magnesium (CTAM) have inhibitory effects on calcium oxalate crystallization, but the effects of CTAM on the matrix proteins of stones in vivo has not been studied. Using an ethylene glycol-induced urolithiasis model, we investigated the effects of CTAM on renal crystallization and the expression of osteopontin (OPN), which is an important stone matrix protein. MATERIALS AND METHODS: Adult Sprague-Dawley rats (200-250gm) were divided randomly into 6 groups of 10 rats. Group 1 was left untreated, and served as a control. Group 2 (CID group) was fed 0.8% ethylene glycol and 1% ammonium chloride (crystal-inducing diet, CID) in drinking water for 4 weeks. Groups 3, 4, 5 and 6 (CTAM groups) were fed the same CID as group 2, but were also treated with either potassium citrate or hydrochlorothiazide or allopurinol or magnesium hydroxide, for 4 weeks, respectively. We biochemically analyzed the 24-hour urine and serum samples. The renal calcium content was measured by atomic absorption. The kidneys were histologically examined for crystal deposit with HandE staining, and for OPN expression with immunohistochemical staining. RESULTS: The grade of calcium oxalate crystal deposits, and renal calcium content, were significantly decreased in the CTAM groups compared to the CID group, which also correlated with the decreased expression of OPN proteins in the kidneys of the CTAM-treated rats. CTAM were all effective in preventing calcium oxalate crystal formation, and decreasing the expression of OPN in rat kidneys. CONCLUSIONS: Our results suggest that CTAM are effective in preventing calcium oxalate stone formation, and that OPN plays an important role in calcium oxalate nephrolithiasis.
Absorption ; Administration, Oral* ; Adult ; Allopurinol* ; Ammonium Chloride ; Animals ; Calcium Oxalate* ; Calcium* ; Citric Acid* ; Crystallization ; Diet ; Drinking Water ; Ethylene Glycol ; Hand ; Humans ; Hydrochlorothiazide ; Kidney ; Magnesium Hydroxide ; Magnesium* ; Nephrolithiasis ; Osteopontin* ; Potassium Citrate ; Rats* ; Rats, Sprague-Dawley ; Urolithiasis*

BACKGROUND: One of the most common complications in patients with end stage renal disease is renal osteodystrophy and parathyroid hormone (PTH) plays a key role in the pathogenesis of renal osteodystrophy. It is known that patients undergoing CAPD (continuous ambulatory peritoneal dialysis) have increased risk of low turnover bone disease and relative hypoparathyroidism is related to its pathogenesis. Factors related to relative hypoparathyroidism are increased in extracellular calcium level, accumulation of aluminum, vitamin D treatment, good control of serum phosphate, diabetes mellitus, and old age. Recently it has been believed that magnesium plays an important role in regulating secretion of PTH. The aim of this study was to evaluate the relationship between serum PTH and serum magnesium as a factor increasing the frequency of relative hypoparathyroidism. METHODS: Author studied 56 patients who had undergone CAPD for more than 6 months without any significant problems and had been followed by Chonnam National University Hospital. No patient had been previously treated with vitamin D or aluminum hydroxide. The patients had used peritoneal dialysate with the magnesium concentration of 0.5 mEq/L. Biochemical parameters were checked. RESULTS: 1. The mean serum magnesium level was 1.99+/-0.36 mEq/L. Among total 56 patients, 15 patients (26.8%) showed hypermagnesemia (serum magnesium > 2.2 mEq/L), and 5 patients (8.9%) showed hypomagnesemia (serum magnesium < 1.6 mEq/L)2. On all 56 patients, serum iPTH level was not correlated with serum magnesium level. But, it was inversely correlated with serum total calcium and ionized calcium levels, respectively (r=-0.365, p=0.006; r=-0.515 p<0.001).3. Among the 49 patients whose serum iPTH level was less than 300 pg/mL, serum iPTH level was inversely correlated with serum magnesium level (r=-0.295, p=0.039), and inversely correlated with serum total calcium and ionized calcium levels, respectively (r=-0.546, p<0.001; r=-0.572 p<0.001).4. Among the 49 patients whose serum iPTH level was less than 300 pg/mL, lower iPTH group (serum iPTH<120 pg/mL) showed higher serum magnesium level (p=0.037), higher serum total calcium level (p<0.001), and lower bone isoenzyme of alkaline phosphatase level (p<0.001) than those of higher iPTH group (120 pg/mL serum< or =iPTH<300 pg/mL). CONCLUSION: Among the CAPD patients whose serum iPTH level was less than 300 pg/mL, there was a significantly inverse correlation between serum iPTH level and serum magnesium level. This study indicates that not only serum calcium level, but also serum magnesium level are important in the regulation of serum iPTH levels of CAPD patients who have been dialyzed by low-magnesium peritoneal dialysate.
Alkaline Phosphatase ; Aluminum ; Aluminum Hydroxide ; Bone Diseases ; Calcium ; Diabetes Mellitus ; Humans ; Hypoparathyroidism ; Jeollanam-do ; Kidney Failure, Chronic ; Magnesium* ; Parathyroid Hormone* ; Peritoneal Dialysis, Continuous Ambulatory* ; Receptors, Calcium-Sensing ; Renal Osteodystrophy ; Vitamin D

BACKGROUND/AIMS: Cholecystectomy is necessary for the treatment of symptomatic or complicated gallbladder (GB) stones, but oral litholysis with bile acids is an attractive alternative therapeutic option for asymptomatic or mildly symptomatic patients. This study was conducted to evaluate the efficacy of magnesium trihydrate of ursodeoxycholic acid (UDCA) and chenodeoxycholic acid (CDCA) on gallstone dissolution and to investigate improvements in gallstone-related symptoms. METHODS: A prospective, multicenter, phase 4 clinical study to determine the efficacy of orally administered magnesium trihydrate of UDCA and CDCA was performed from January 2011 to June 2013. The inclusion criteria were GB stone diameter < or =15 mm, GB ejection fraction > or =50%, radiolucency on plain X-ray, and asymptomatic/mildly symptomatic patients. The patients were prescribed one capsule of magnesium trihydrate of UDCA and CDCA at breakfast and two capsules at bedtime for 6 months. The dissolution rate, response rate, and change in symptom score were evaluated. RESULTS: A total of 237 subjects were enrolled, and 195 subjects completed the treatment. The dissolution rate was 45.1% and the response rate was 47.2% (92/195) after 6 months of administration of magnesium trihydrate of UDCA and CDCA. Only the stone diameter was significantly associated with the response rate. Both the symptom score and the number of patients with symptoms significantly decreased regardless of stone dissolution. Adverse events necessitating discontinuation of the drug, surgery, or endoscopic management occurred in 2.5% (6/237) of patients. CONCLUSIONS: Magnesium trihydrate of UDCA and CDCA is a well-tolerated bile acid that showed similar efficacy for gallstone dissolution and improvement of gallstone-related symptoms as that shown in previous studies.
Adult ; Aged ; Antacids/*administration & dosage ; Chenodeoxycholic Acid/*administration & dosage ; Cholagogues and Choleretics/*administration & dosage ; Drug Administration Schedule ; Drug Combinations ; Female ; Gallstones/*drug therapy ; Humans ; Magnesium Hydroxide/*administration & dosage ; Male ; Middle Aged ; Prospective Studies ; Severity of Illness Index ; Solubility/drug effects ; Ursodeoxycholic Acid/*administration & dosage