ABSTRACT
DNA adducts are regarded as individual internal dosimeters for the exposure to chemical carcinogens. To date, the most sensitive method for DNA adduct analysis is the radioactive 32P-postlabeling method, which allows the detection of one adduct in 10(10) unmodified nucleotides in microg amounts of DNA. However, this technique suffers from disadvantages such as working with radioactive phosphorus and time-consuming chromatographic separation procedures. In addition, the simultaneous detection of adducts from different classes of carcinogens in a DNA sample is difficult. In order to overcome these drawbacks, we are developing a new detection method, comprising fluorescence labeling of DNA adducts, capillary electrophoretic (CE) separation, and on-line detection by monitoring laser-induced fluorescence (LIF). So far, we have evaluated the separation power and the detection limit of CE with fluorescently labeled standard compounds such as unmodified nucleotides or alkylated thymidines. For this purpose, we developed a universal method for labeling 5'-OH-mononucleosid-3'-dicyanoethyl-phosphates with fluorescent dyes based on the phosphoramidite technology for DNA synthesis. The separation of N3-methylated, N3-, O2- and O4-butylated thymidines from the unmodified nucleotide within a few minutes recommends CE-LIF as a powerful method for DNA adduct analysis.
Subject(s)
DNA Adducts/chemical synthesis , Alkylation , Chromatography, High Pressure Liquid , DNA Adducts/chemistry , DNA Adducts/isolation & purification , Electrophoresis, Capillary/methods , Fluorescent Dyes , Molecular Structure , Reference Standards , Sensitivity and Specificity , Spectrometry, Fluorescence , Spectrophotometry, Ultraviolet , Thymidine/analogs & derivatives , Thymidine/chemistry , Thymidine/isolation & purificationABSTRACT
Cancer chemotherapy is a new and important medical science and much interest has been focused on catechins, not only for their antioxidant activity, but also because of their known antimutagenic and antitumorigenic properties. Green tea and black tea, which are among the most popular beverages consumed worldwide, contain many different catechins. We developed an analytical method capable of separating six different catechins and caffeine in tea by micellar electrokinetic chromatography in only 20 min without extensive sample preparation. Furthermore, we compared the amount of catechins and caffeine in several teas and different preparation modes.
Subject(s)
Caffeine/analysis , Catechin/analysis , Tea/chemistry , Chromatography, Micellar Electrokinetic Capillary/methods , Molecular Structure , Plant Extracts/chemistry , Reproducibility of ResultsABSTRACT
Three internal and three external outcome measures generated data for this longitudinal study. The internal outcome measures were nursing GPA, nonnursing GPA, and clinical evaluations of students during eight clinical rotations. The external evaluations were NCLEX scores, the graduates' self-rating of their competency in meeting program objectives, and their immediate supervisors' ratings on the identical competency rating scale. Data analyzed using Pearson correlation coefficients revealed significant correlations among all internal measures of academic outcomes with one external measure, the NCLEX score. There was no correlation between any nursing measure of outcome and the supervisor's ratings. There was a modest correlation between the supervisors' rating and the nonnursing GPA. The faculty clinical evaluation was the only significant correlation found between the alumni rankings and any other measure of outcome. There was no correlation between the supervisors' and the graduates' ratings.
Subject(s)
Educational Measurement/methods , Nursing Education Research/methods , Adult , Clinical Competence , Educational Measurement/standards , Educational Status , Evaluation Studies as Topic , Faculty, Nursing , Female , Humans , Licensure, Nursing , Male , Nursing Education Research/standards , Reproducibility of ResultsABSTRACT
A rapidly growing number of California's ethnic minority nursing students are individuals whose primary language is not English; these English-as-a-second-language (ESL) students often have high attrition rates. This research surveys the approaches used in all of California's 21 generic baccalaureate nursing programs to retain their ESL students until graduation. Comparisons between the five programs with the highest ESL student retention rates and the group as a whole show significant differences.
