Biomedical subjects

Eric A E Garber

Publications and source records attributed to Eric A E Garber.

4 recordsLinked to original sources

PubMed2005

Feasibility of immunodiagnostic devices for the detection of ricin, amanitin, and T-2 toxin in food.

Qualitative and quantitative comparisons were conducted of commercially available immunodiagnostic devices for the detection of three select agents with oral LD50 values > or = 0.1 mg/kg of body weight. Ricin (oral LD50 > 1 mg/kg), amanitin (oral LD50 approximately 0.1 mg/kg), and T-2 toxin (oral LD50 > 1 mg/kg) were spiked into beverages, produce, dairy, and baked goods and assayed using commercially available enzyme-linked immunosorbent assays (ELISAs) and lateral flow devices. In all cases, the commercial diagnostic kits successfully detected all three select agents at concentrations below what might be a health concern. The considerable difference between the limit of detection of the immunodiagnostic devices employed (typically < or = 0.020 microg/g) and the amount of the select agent necessary to pose a health threat in a single serving of food facilitated the design of protocols for the high throughput screening of food samples. These protocols entailed simple extraction methods followed by sample dilution. Lateral flow devices and sandwich ELISAs for the detection of ricin had no significant background problems due to the food matrices. Competitive ELISAs, which typically have unacceptably high background reactions with food samples, successfully detected amanitin and T-2 toxin.

Amanitins↗

PubMed2004

Low levels of sodium and potassium in the water from wetlands in Minnesota that contained malformed frogs affect the rate of Xenopus development.

Water samples were collected between 1999 and 2000 from wetlands in Minnesota that contained malformed frogs. The water samples were analyzed for 14 minerals/ions and screened for the presence of biologically active compounds using Xenopus laevis. Results indicated that water from two sites, CWB and ROI2, induced severe retardation with embryo lengths reduced 20% after 96 hr of development. The developmental delay observed with water from ROI2 was alleviated by supplementation with sodium, while both sodium and potassium alleviated the developmental delay observed with water whose mineral content mimicked that of CWB. Seasonal fluctuations in the sodium and potassium content at ROI2 and NEY correlated with changes in the rates of Xenopus development. Xenopus embryos reared on water from ROI2 for 120 hr displayed gut malformations not present in embryos reared on a synthetic media designed to mimic the mineral content of the water from ROI2. Embryos reared on water from ROI2 supplemented with minerals at levels comparable to that routinely employed in the rearing of Xenopus were neither retarded nor malformed. It is proposed that climate driven hydrology may influence the mineral composition at selected wetlands and delay development which may alter window(s) of susceptibility towards biologically active agents and the occurrence of malformed frogs.

Animals↗

PubMedDate not supplied

Mineral deficiency and the use of the FETAX bioassay to study environmental teratogens.

The Frog Embryo Teratogenesis Assay: Xenopus (FETAX) bioassay has been employed extensively to screen compounds for teratogenic activity. Recent laboratory studies have indicated that low potassium concentrations retard Xenopus laevis development. The effects of varying concentrations of minerals on Xenopus laevis embryo length and development were examined to determine the utility of the FETAX bioassay in the study of environmental teratogens. Water samples collected from 18 wetlands in Minnesota and North Dakota correlated with low mineral levels, causing delayed embryonic development in the FETAX bioassay. When the concentration of sodium or potassium was <5 ppm, Xenopus laevis development was delayed. As a result, it was difficult to assess teratogenic activity after 96 h of incubation. Furthermore, the length of the embryos-an indication of development-paralleled changes in mineral composition. Comparisons between different wetlands based on changes in one specific mineral were not possible due to a synergism between various minerals. If the concentration of sodium and/or potassium was <5 ppm but > or =2 ppm, extension of the FETAX bioassay to 120 h allowed organogenesis to proceed through stage 46, as required for scoring in accordance with ASTM guidelines for the FETAX bioassay. In those cases in which the concentration of sodium and/or potassium were <2 ppm, the embryos could not develop to stage 46 within 120 h and the FETAX bioassay was not suitable for detecting teratogenic activity. Published in 2002 by John Wiley & Sons, Ltd.

Animals↗

PubMedDate not supplied

Performance Tested Method multiple laboratory validation study of ELISA-based assays for the detection of peanuts in food.

Performance Tested Method multiple laboratory validations for the detection of peanut protein in 4 different food matrixes were conducted under the auspices of the AOAC Research Institute. In this blind study, 3 commercially available ELISA test kits were validated: Neogen Veratox for Peanut, R-Biopharm RIDASCREEN FAST Peanut, and Tepnel BioKits for Peanut Assay. The food matrixes used were breakfast cereal, cookies, ice cream, and milk chocolate spiked at 0 and 5 ppm peanut. Analyses of the samples were conducted by laboratories representing industry and international and U.S governmental agencies. All 3 commercial test kits successfully identified spiked and peanut-free samples. The validation study required 60 analyses on test samples at the target level 5 microg peanut/g food and 60 analyses at a peanut-free level, which was designed to ensure that the lower 95% confidence limit for the sensitivity and specificity would not be <90%. The probability that a test sample contains an allergen given a prevalence rate of 5% and a positive test result using a single test kit analysis with 95% sensitivity and 95% specificity, which was demonstrated for these test kits, would be 50%. When 2 test kits are run simultaneously on all samples, the probability becomes 95%. It is therefore recommended that all field samples be analyzed with at least 2 of the validated kits.

Allergens↗