Urine recovery

Figure 8 shows typical chromatograms for spiked and unspiked rat urine. Recovery was found to be 50, 55, and 35% for three replicate samples spiked at the 2 yg/L level, which we have found to be typical recovery values for trace levels of DCB in aqueous media (e.g. industrial wastewater). 

No significant stereoselectivity in etodolac enantiomeric metabolism was noted in a 24 hour urine recovery study [40]. Analytical methods for the... 

The extent of absorption also was assessed by comparing the 12-hour urine recovery of NAPA and NAPA- C. A correction was made to the NAPA recovery to compensate for the lag in NAPA absorption that was observed after the oral dose was administered. The results of these two methods of assessing extent of absorption are compared in Table 4.3. The discrepancy was less than 2% for all but one of the subjects. 

Koyama et al. (1980) studied the pharmacology of SM-1652 in humans. Initial serum concentrations obtained after a bolus intravenous injection of 1 g of SM-1652 were 303 p-g/ml (Table XII), with 8.2 xg/ml still measured 24 hr after dosage. The plasma half-life (P) was in excess of 5 hr. The protein binding in human serum was 96.3%. The 24-hr urine recovery was 25%. A significant although variable amount of SM-1652 is excreted via the bile in humans. No biologically active metabolites have been observed. 

Lores EM, Bradway DE. 1977. Extraction and recovery of organophosphorus metabolites from urine using an anion exchange resin. J Agric Food Chem 25 75-79. 

Radioactivity Analysis. Samples of urine, feces, and tissues were combusted to COo and analyzed for radioactivity (5). By using this method the recovery of radioactivity from samples spiked with C was 95 dt 5%. To determine the radioactivity expired as CO2, 5-ml aliquots of the solution used to trap the CO2 were added to 15 ml of a scintillation counting solution containing 4 grams 2,5-diphenyloxazole (PPO) and 0.1 grams l,4-bis-2(5-phenyloxazolyl)-benzene (POPOP) per liter of 1 1 toluene 2-methoxyethanol. Samples were counted for radioactivity in a Nuclear Chicago Mark II liquid scintillation counter. Counting eflSciency was corrected by the internal standard technique. 

The positions, numbers, and types of sugars on the anthocyanin molecule influence its bioaccessibility. Indeed, a recent human study reported that the acylation of anthocyaifins resulted in a sigififlcant decrease of anthocyanin recoveries in plasma and urine. In addition, anthocyanins form linkages with aromatic acids, aliphatic acids, and methyl ester derivatives, which can also affect their passage through the intestinal barrier. 

Despite their potential health-promoting effects as dietary antioxidants, the fate of betalains in humans has been poorly studied. Betalain bioavailability was first demonstrated in humans by the appearance of betacyanins in urines after ingestion of beetroot extract" and red beet juice," indicating that these compounds are indeed absorbed. Although intact betacyanins (betanin and isobetaiun) appeared rapidly in human urine with a maximum excretion rate observed within 2.5 to 8 hr," betacy-anin recoveries in human urine were usually low (< 1% of the dose) over 24 hr postdose, suggesting that either the bioavailabifity of betacyaiuns from red beetroot is low or that renal clearance is a minor excretion route for these compounds. 

Urine was analyzed for atrazine, DEA, DIA, and DACT at the O.I-IOO agkg concentration range but detailed recovery information was not provided. A 5-mE urine sample was mixed in a tube for 15 min with 5mE of diethyl ether and 0.7 g of sodium chloride. After separation of the layers, the aqueous fraction was mixed with 5 mL of ethyl acetate for a second partitioning step. The two organic fractions... 

There is significant controversy over the role of loop diuretics in the treatment of ARE Theoretical benefits in hastening recovery of renal function include decreased metabolic oxygen requirements of the kidney, increased resistance to ischemia, increased urine flow rates that reduce intraluminal obstruction and filtrate backleak, and renal vasodilation.6 Theoretically, these effects could lead to increased urine output, decreased need for dialysis, improved renal recovery, and ultimately, increased survival. However, there are conflicting... 

To 100-gram batches of 1-day-old samples of cow s urine were added 0.05, 0.1, and 0.5 mg. of Compound 118 in acetone to give 0.5, 1.0, and 5.0 p.p.m., respectively. The urines were then extracted with two 50-ml. batches of hexane. Occasional emulsions were broken by centrifuging. The hexane extracts were dried with anhydrous sodium sulfate, filtered, evaporatively concentrated, and analyzed for Compound 118 as described under Procedure. The results of these analyses are shown in Table IV. Similar experiments with human urine gave slightly better recoveries. 

Fig. 20 Percentage xylose dose recovered in urine as a function of age after a 5 g intravenous dose (A), 5 g oral dose (B), and 25 g oral dose (C). Line D is the ratio of urinary recoveries (oral to intravenous) after 5g doses (y-axis on right). Symbols represent data obtained from different studies. (From Ref. 155.)...

Low levels of 3,5,6-TCP were also observed in pre-exposure urine from most of the field workers. These 3,5,6-TCP levels were subtracted from urine field recovery samples and were used to correct levels of 3,5,6-TCP found in the post-exposure urine samples from these same workers. This procedure was necessary to calculate the amount of 3,5,6-TCP in the urine that was attributable to the exposure period. 

Acute drug-related hypersensitivity reactions (allergic responses) may cause tubulointerstitial nephritis, which will damage the tubules and interstitium. These reactions are most commonly observed with administration of methicillin and other synthetic antibiotics as well as furosemide and the thiazide diuretics. The onset of symptoms occurs in about 15 days. Symptoms include fever, eosinophilia, hematuria (blood in the urine), and proteinuria (proteins in the urine). Signs and symptoms of acute renal failure develop in about 50% of the cases. Discontinued use of the drug usually results in complete recovery however, some patients, especially the elderly, may experience permanent renal damage. 

Bergstrom et al. [63] used HPLC for determination of penicillamine in body fluids. Proteins were precipitated from plasma and hemolyzed blood with trichloroacetic acid and metaphosphoric acid, respectively, and, after centrifugation, the supernatant solution was injected into the HPLC system via a 20-pL loop valve. Urine samples were directly injected after dilution with 0.4 M citric acid. Two columns (5 cm x 0.41 cm and 30 cm x 0.41 cm) packed with Zipax SCX (30 pm) were used as the guard and analytical columns, respectively. The mobile phase (2.5 mL/min) was deoxygenated 0.03 M citric acid-0.01 M Na2HP04 buffer, and use was made of an electrochemical detector equipped with a three-electrode thin-layer cell. The method was selective and sensitive for mercapto-compounds. Recoveries of penicillamine averaged 101% from plasma and 107% from urine, with coefficients of variation equal to 3.68 and 4.25%, respectively. The limits of detection for penicillamine were 0.5 pm and 3 pm in plasma and in urine, respectively. This method is selective and sensitive for sulfhydryl compounds. 

Studies on workers in an occupational setting showed a dose-response relationship between the concentration of acrylonitrile of inspired air and the recovery of metabolites in the urine (Houthuijs et al. 1982 Sakurai et al. 1978). In a controlled study using human volunteers, urinary metabolite data suggested that the elimination of acrylonitrile followed first-order kinetics, with a half- life of seven to eight hours (Jakubowski et al. 1987). 

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