Analytical methods have been developed for the detection and quantification of cyclosporin A (CsA) in blood using time-of-flight secondary-ion mass spectrometry (TOF-SIMS) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI/TOF-MS). Linear calibration curves were obtained for both methods in the range 25-2000 ng/mL in whole blood. The limit of detection (LOD) and limit of quantification (LOQ) were determined to be 7 and 23 ng/mL, respectively, for the TOF-SIMS method; the LOD and LOQ were 10 and 33 ng/mL, respectively, for the MALDI/TOF-MS method. Coefficients of variation ranged from 3 to 5% for the TOF-SIMS method and from 4 to 8% for the MALDI/TOF-MS method. Blood samples were also analyzed by a nonspecific method, fluorescence polarization immunoassay (FPIA), and by a specific method, high-performance liquid chromatography (HPLC). The TOF-MS results are in good agreement with the HPLC results, but not with the FPIA results. The TOF-MS methods can also provide information about CsA metabolites.
A controlled evaluation was made of the efficacy of copper-silver ionization in eradicating Legionella pneumophila from a hospital water supply. Copper-silver ionization units were installed on the hot water recirculation line of one building with water fixtures positive for Legionella species. Another building with the same water supply served as a control. Legionella species persisted within the system when copper and silver concentrations were < 0.3 and < 0.03 ppm, respectively. When copper and silver concentrations were > 0.4 and > 0.04 ppm, respectively, there was a significant decrease in Legionella species colonization, but the percentage of water fixtures positive for organisms was unchanged in the control building. When the ionization unit was inactivated, water fixtures continued to be free of Legionella species for 2 additional months. Copper-silver ionization can eradicate L. pneumophila in a water distribution system. The advantages of copper-silver ionization include relatively low cost, straightforward installation, easy maintenance, nontoxic by-products and the presence of a disinfecting residual.
SUMMARY Nine weU-motirated adults, knowledgeable about nutrition, kept food records, sared food portions equal to what had been eaten, and collected 24-hour urine samples for 3 consecutive days. Estimates of sodium and potassium intake were calculated from food table analyses of written food records and from flame photometric analyses of food portions. For each subject the mean of the estimates for each of the 3 days was compared with the mean of urine analyses for sodium and potassium for each of the 3 days. For the group of nine subjects, the average estimate of sodium intake from analyses of food records was 11% lower than the average estimate of urinary sodium excretion; the average estimate of sodium intake from analysis of food portions was 2% higher than urinary sodium excretion. For individuals, there were large differences between estimates of intake and measurement of sodium excretion. For the group of nine subjects, the average estimate of potassium intake from analysis of food records was less than 1% lower than the average estimate of potassium urinary excretion; the average estimate of potassium intake from analysis of food portions was 13% higher than potassium urinary excretion. For individuals, as with sodium, there were large differences between estimates of intake and measurement of potassium excretion. (Hypertension 2: 695-699, 1980) KEY WORDS * sodium • potassium • urinary excretion measurements T HE PURPOSE of this study was to determine whether in free living adults measurement of sodium and potassium from food ingested yields a valid estimate of sodium and potassium excreted in the urine. This is of interest because 24-hour urinary excretion, which is believed to provide the best estimate of sodium intake, cannot be measured in free living infants and is difficult to measure in free living adults. In a prior study of 6-month-old infants, sodium intake was assessed from food records, and a positive association was found between sodium intake and systolic blood pressure.1 When the infants were reexamined at 15 months of age, the association between sodium intake and systolic pressure was no longer present. We wondered whether the more complex food intakes of 15-month-old infants rendered the assessment of sodium intake from food records invalid.
We conducted a prospective environmental study for Legionella pneumophila in 15 hospitals in Pennsylvania. Hot water tanks, cold water sites, faucets, and show-erheads were surveyed four times over a one-year period. Sixty percent (9/15) of hospitals surveyed were contaminated with L pneumophila. Although contamination could not be linked to a specific municipal water supplier, most of the contaminated supplies came from rivers. Parameters found to be significantly associated with contamination included elevated hot water temperature, vertical configuration of the hot water tank, older tanks, and elevated calcium and magnesium concentrations of the water (P < 0.05). This study suggests that L pneumophila contamination could be predicted based on design of the distribution system, as well as physicochemical characteristics of the water.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.