Oxalate, Urinary

Dissolution of Human Urinary Calculi in Vitro. Five human urinary calculi containing various proportions of Ca3(P04)2, Ca(C204), CaC03, and MgNH4(P04) were subjected to similar dissolution tests at pH 7 (Table 11). The same dissolution patterns as those of the model phosphate and oxalate calculi are found. That is, for phosphate calculi no. 1-4, X is more effective than [18]aneN6 or EDTA and for oxalate calculus no. 5, EDTA is best. 

Following oral administration of a lethal dose to a dog (25 mg. per kg. wettable powder) tissues taken immediately after death analyzed as follows no parathion recovered from bladder bile, liver, kidney, abdominal fat, saliva, or intestine small quantities (2 to 7 p.p.m.) of parathion recovered from oxalated blood, spleen, lung, brain, and spinal cord. The urinary bladder was strongly contracted and no urine could be collected. The results of these two experiments indicate a universal distribution of parathion following acutely lethal doses. 

Calcium oxalate (723) occurs as the monohydrate (whewellite, the thermodynamically stable form under ambient conditions (724)), the dihydrate (weddellite) in plant calcium stores and in sap, or the trihydrate (725). Calcium oxalate also plays a structural role in plants. Oxalate, for example from excessive amounts of rhubarb or spinach, inhibits absorption of Ca2+ from the GIT precipitation of calcium oxalate is the reason for the toxicity of oxalates. Calcium oxalate may also occur in man, where it can appear as minute star-shaped crystals in the urine. It is the main constituent of the majority of urinary calculi in man (726,727). The relationships between dietary calcium... 

Bricker et al. (30) reported that there were no statistically significant differences between the calcium balances of eight women on cocoa and non-cocoa diets. The women were studied for three to seven 4-day periods. Calcium intake was 670 mg/day with the addition of milk and 679 and 755 mg/day with the addition of milk and cocoa. Five levels of cocoa, supplying from 5.6-52.6 g/day, were tested. These amounts would likely contain from 25-280 mg of oxalic acid, which was not nearly as much as was added when spinach was fed. With the inclusion of cocoa in the diet, the urinary calcium fell and fecal calcium rose. There were also increases in the fecal excretion of dry matter and nitrogen. 

There is little reported information on industrial exposure, although chronic inflammation of the upper respiratory tract has been described in a worker exposed to hot vapor arising from oxalic acid. Ingestion of as little as 5 g has caused fatalities there is rapid onset of shock, collapse, and convulsions. The convulsions are thought to be the result of hypocalcemia due to the calcium-complexing action of oxalic acid, which depresses the level of ionized calcium in body fluids. Marked renal damage from deposition of calcium oxalate may occur. A study of railroad car cleaners with heavy exposure to oxalic acid solutions found an increased incidence of urinary stones. There was a 53% incidence of urolithiasis in exposed workers compared with a rate of 12% in unexposed workers from the same company. ... 

Urinary oxalate Some patients may develop increased levels of urinary oxalate following treatment. Exercise caution in patients with a history of hyperoxaluria or calcium oxalate nephrolithiasis. 

Coriander Coriandrum sativum) Uses t Appetite, treat D, dyspep-sia, flatulence Action Stimulates gastric secretions, spasmolytic effects Available forms Tine 10-30 gtts PO OD Contra w/ PRG or lactation Notes/SE N/V, fatty liver tumors, allergic skin Rxns Interactions T Effects OF oral hypoglycemics EMS T Risk of photosensitivity Rxns may cause hypoglycemia Cranberry [Vaeeinium macreearpon) Uses Prevention UTI urinary deodorizer in urinary incontinence Actions Interferes w/ bacterial adherence to epithelial cells of the bladder Available forms Caps 300-500 mg PO bid-qid unsweetened juice 8-16 oz daily tine 3-5 mL or tincture 1/2-1 tsp up to 3X/d, tea 2-3 tsps of dried flowers/cup creams apply topically 2-3X/d PO SE D, irritation, nephrolithiasis if T urinary Ca oxalate Interactions T Effects OF warfarin ... 

The presence of Ca in kidney stones and the abnormally high Ca levels in idiopathic (absorptive) hypercalciuric individuals that are inherently more prone to kidney stones, initially led to the belief that dietary Ca may be a cause of renal stone formation (Coe et al., 1992). Recent evidence suggests that, as a therapeutic approach to reducing the risk for kidney stones, Ca-restricted diets may pose a greater risk to normocalciuric individuals prone to kidney stone formation such an approach may increase urinary oxalate and the likelihood of recurrent stones, as well as promote bone loss (Borghi et ah, 2002 Coe et al., 1997 Curhan et ah, 1997). The amoimt of oxalate excreted in urine has been foimd to be positively associated with Ca oxalate supersaturation and stone formation (Holmes et ah, 2001). While free oxalic acid is readily absorbed from the gut lumen (Morozumi et ah, 2006), an increased dietary Ca to oxalate... 

Six subjects also completed 24-h oxalate excretion and absorption tests so that the effectiveness of various Ca doses (100, 200, and 300 mg Ca) in conjunction with an OL versus baseline (0 mg Ca) could be assessed. Total urinary oxalate excretion was significantly reduced in the presence of Ca at all doses, although endogenous oxalate remained unchanged. Zero mg Ca and 100 mg Ca resulted in higher oxalate absorption (11.3% and 9.1%, respectively) compared to 200 mg Ca (5.9%) and 300 mg Ca (7.6%). 

In both sexes, CCM-OJ provided an alkali load that significantly increased urinary pH compared to basal levels and versus milk consumption, and also increased urinary citrate excretion versus basal levels. An elevated urine pH and citrate level are generally considered to reduce Ca oxalate supersaturation and crystallization potential (Odvina, 2006). However, in this study the relative supersaturation measurement for Ca oxalate was not different between the CCM-OJ and milk treatment groups, or between either treatment and the basal levels. Although the alkalizing effect of milk was less than that of CCM-OJ, it also induced a higher urinary pH compared to basal levels (p <. 01 and p <. 05 in women and men, respectively). 

Liebman, M., and Chai, W. (1997). Effect of dietary calcium on urinary oxalate excretion after oxalate loads. Am. ]. Clin. Nutr. 65,1453-1459. 

Mechanism of Action A nonabsorbable compound that alters urinary composition of calcium, magnesium, phosphate, and oxalate. Calcium binds to cellulose sodium phosphate, thus preventing intestinal absorption of it. Therapeutic Effect Prevents the formation of kidney stones. 

Approximately two thirds of kidney stones contain Ca2+ phosphate or Ca2+ oxalate. Many patients with such stones exhibit a defect in proximal tubular Ca2+ reabsorption that causes hypercalciuria. This can be treated with thiazide diuretics, which enhance Ca2+ reabsorption in the distal convoluted tubule and thus reduce the urinary Ca2+ concentration. Salt intake must be reduced in this setting, since excess dietary NaCI will overwhelm the hypocalciuric effect of thiazides. Calcium stones may also be caused by increased intestinal absorption of Ca2+, or they may be idiopathic. In these situations, thiazides are also effective, but should be used as adjunctive therapy with other measures. 

Achyranthes japonica (Miq.) Nakai Japan Niu Teng (Japanese chaff flower) (leaf, root) Calcium oxalate, saponin, oleaolic acid, ecdysterone, inokosterone.50 Antirhymatic, anodyne, treat amenorrhea, carbuncles, fever, dystocia, and urinary ailments. 

Oxalis corriculaza L. O. corymbosa DC Sha Jiang Cao (Wood sorrel) (leaf) Oxalate, vitamin C, calcium, citric acid, malic acid, tartaric acid.50 Antidote to arsenic and mercury, for bruises, clots, diarrhea, fever, influenza, snakebite, urinary infections. 

Ion chromatography high-performance liquid chromatography (HPLC) is the method of choice for the quantification of oxalate, glycolate, and glycerate [3,4]. In addition, preservation and storage of the liquid samples may influence the stability of oxalate and glycolate. Use of urinary filter spots is a practical alternative approach for the collection and safe transport of samples to be analyzed for many metabolic disorders [5]. 

Ascorbic acid is the main endogenous precursor of oxalic acid and in healthy persons up to 30% of urinary oxalate can originate from ascorbate. Ascorbate is extremely unstable in neutral and alkaline solutions and degrades to oxalate nonenzymatically [6]. Acidification to pH 1-2 is required to prevent deposition of insoluble Ca-oxalate. 

Table 3.5.3 Reference values for urinary oxalate, glycolate, citrate, glycerate (given in mmol/mol creatinine), and sulfate (given in mol/mol creatinine), and plasma oxalate, citrate, and sulfate (given in fimol/l)...

Trichloroethane is rapidly absorbed after inhalation, oral administration and application to the skin in rodents. 1,1,2-Trichloroethane is extensively metabolized in mice given 100-200 mg/kg bw by intraperitoneal injection, 73-87 % of the dose being eliminated in the urine and 16-22% in expired air. Several urinary metabolites have been identified chloroacetic acid, S-carboxymethyl-i,-cysteine, thiodiacetic acid, 2,2-dichloroethanol and oxalic acid (lARC, 1991). 

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