Nutrition Screening Tool for Every Preschooler (NutriSTEP): validation and test-retest reliability of a parent-administered questionnaire assessing nutrition risk of preschoolers.

OBJECTIVES: Study 1: To establish the validity of scores on Nutrition Screening Tool for Every Preschooler (NutriSTEP), a community-based parent-administered screening tool for assessing nutrition risk, by comparing scores to an expert rating. Study 2: To demonstrate test-retest reliability of NutriSTEP. SUBJECTS/METHODS: Study 1: Parents of 269 preschoolers (of 294 parents recruited from the community), completed the NutriSTEP questionnaire; a registered dietitian (RD) assessed the nutritional status (based on medical and nutritional history, 3 days of dietary recall and anthropometric measurements) of these preschoolers and rated their nutritional risk (1 (low) to 10 (high risk)). Receiver operating characteristic (ROC) curves were used to establish validity and determine appropriate cut points based on sensitivity and specificity. Study 2: Parents of 140 preschoolers (of 161 recruited) completed NutriSTEP on two occasions. Intraclass correlation (ICC) and kappa were used to assess reliability. RESULTS: Study 1: Scores on NutriSTEP and the RD rating were correlated (r=0.48, P=0.01). Area under the ROC curve for the high risk RD rating (score 8+) and the moderate risk rating (score 5+) were 81.5 and 73.8%, respectively. A moderate risk cut point of >20 and high risk cut point of >25 were identified for the NutriSTEP scores. Study 2: The NutriSTEP score was reliable between administrations (ICC=0.89, F=16.7, P<0.001). Most items on the questionnaire had adequate (kappa>0.5) or excellent (kappa>0.75) agreement. CONCLUSIONS: The NutriSTEP questionnaire is both valid and reliable for determining nutritional risk in preschoolers.

Diphenylhydantoin is not genotoxic in a battery of short-term cytogenetic assays.

5,5-Diphenylhydantoin (DPH) is an antiepileptic drug associated with an increase in malformations in infants born to women taking DPH during pregnancy. Positive and negative results have been reported by various investigators for in vivo and in vitro chromosome aberration (CAB) assays, in vivo and in vitro sister chromatid exchange (SCE) assays, and in vivo micronucleus tests (MNT). In this laboratory, DPH was tested in an in vitro CAB assay using Chinese hamster ovary cells with and without an S-9 activation system, an in vivo SCE assay in female CD-1 mice, an in vivo MNT, using both male and female CD-1 mice, and a transplacental micronucleus test. The results from this comprehensive battery of cytogenetic tests were uniformly negative and support a conclusion that the known teratogen, DPH, is not clastogenic.

Expulsion of demecolcine-induced micronuclei from mouse bone marrow polychromatic erythrocytes.

The mouse micronucleus test is a valuable tool for evaluating in vivo chromosome damage produced by test articles in polychromatic erythrocytes of bone marrow. Compounds that are clastogens, such as cyclophosphamide, induce micronuclei that are smaller than those induced by compounds that are spindle poisons, such as demecolcine. In vitro studies have previously shown that the frequency of mitomycin C- and vincristine-induced micronuclei in mouse L-929 cells was reduced due to micronuclear extrusion following treatment with cytochalasin B. The current study shows that micronuclei are also expelled in vivo, that expulsion is dependent upon micronuclear size, and that observation of these extruded micronuclei is dependent upon the method of sample preparation.

The evaluation of a multiple dosing protocol for the mouse bone-marrow micronucleus assay using benzidine and 2,6-xylidine.

Male ICR mice were treated with 1, 2 or 3 daily doses of either benzidine or 2,6-xylidine. Groups of 5 animals were sacrificed 24 h after the last dose and the bone marrow examined for micronuclei. Benzidine was given at dose levels of 40 and 200 mg/kg and 2,6-xylidine was given at dose levels of 75 and 375 mg/kg. These doses represent 10 and 50% of the respective median lethal doses. Benzidine produced a significant (p less than 0.001) dose related increase in the incidence of micronucleated polychromatic erythrocytes (MPE), while 2,6-xylidine had no effect on the frequency of micronucleated cells. Statistical analyses of the data indicated that the incidence of MPE was independent of the number of doses administered prior to bone marrow harvest.

Mutagenicity evaluation of HC Blue No. 1 and HC Blue No. 2, I. Effect on the induction of micronuclei in mouse bone marrow cells.

Two hair-dye chemicals, HC Blue No. 1 and HC Blue No. 2, were assessed for the ability to produce chromosome breakage and/or spindle malformation in vivo by evaluating the capacity of these compounds to induce micronuclei in polychromatic erythrocytes of mouse bone marrow. Initial studies were conducted in ICR male and female mice given a single intraperitoneal dose of 1000, 500 or 250 mg/kg body weight and examined for micronucleus induction 24 or 48 h later. Activity was observed in female mice given 1000 mg/kg of HC Blue No. 1 at the 24-h harvest time. A questionable response was noted with HC Blue No. 2 in males at the 1000 mg/kg, 24-h time point. No activity was observed in either sex at the 48-h harvest time. In a second set of studies, mice from two strains, ICR and CD-1, were administered a single intraperitoneal dose of 1000 mg/kg of each chemical and the bone marrow was extracted 24 h later. In these experiments, HC Blue No. 1 again produced a statistically significant elevation of micronuclei in female ICR mice. No significant effect was observed in CD-1 mice of either sex. HC Blue No. 2 did not produce any significant elevation of micronuclei in either sex of ICR or CD-1 mice.