In this study, structural equation modeling is applied to examine the determinants of students' satisfaction and their perceived learning outcomes in the context of university online courses. Independent variables included in the study are course structure, instructor feedback, self-motivation, learning style, interaction, and instructor facilitation as potential determinants of online learning. A total of 397 valid unduplicated responses from students who have completed at least one online course at a university in the Midwest were used to examine the structural model. The results indicated that all of the antecedent variables significantly affect students' satisfaction. Of the six antecedent variables hypothesized to affect the perceived learning outcomes, only instructor feedback and learning style are significant. The structural model results also reveal that user satisfaction is a significant predictor of learning outcomes. The findings suggest online education can be a superior mode of instruction if it is targeted to learners with specific learning styles (visual and read/write learning styles) and with timely, meaningful instructor feedback of various types.

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Escherichia coli purine nucleoside phosphorylase (PNP) expressed in tumors converts relatively nontoxic prodrugs into membrane-permeant cytotoxic compounds with high bystander activity. In the present study, we examined tumor regressions resulting from treatment with E. coli PNP and fludarabine phosphate (F-araAMP), a clinically approved compound used in the treatment of hematologic malignancies. We tested bystander killing with an adenoviral construct expressing E. coli PNP and then more formally examined thresholds for the bystander effect, using both MuLv and lentiviral vectoring. Because of the importance of understanding the mechanism of bystander action and the limits to this anticancer strategy, we also evaluated in vivo variables related to the expression of E. coli PNP (level of E. coli PNP activity in tumors, ectopic expression in liver, percentage of tumor cells transduced in situ, and accumulation of active metabolites in tumors). Our results indicate that F-araAMP confers excellent in vivo dose-dependent inhibition of bystander tumor cells, including strong responses in subcutaneous human glioma xenografts when 95 to 97.5% of the tumor mass is composed of bystander cells. These findings define levels of E. coli PNP expression necessary for antitumor activity with F-araAMP and demonstrate new potential for a clinically approved compound in solid tumor therapy.

To cite this article: Wen H‐J, Wang Y‐J, Lin Y‐C, Chang C‐C, Shieh C‐C, Lung F‐W, Guo YL. Prediction of atopic dermatitis in 2‐yr‐old children by cord blood IgE, genetic polymorphisms in cytokine genes, and maternal mentality during pregnancy. Pediatric Allergy Immunology 2011; 22: 695–703. Abstract Atopic dermatitis (AD) is the most common skin disease in childhood and the first step of atopic march. This study aimed to investigate whether AD in children could be better predicted by biologic markers (cord blood IgE [cbIgE], LT‐αNcoI alleles, and FcεRI‐β E237G genotypes) and maternal mentality during pregnancy, taking into account gender, socio‐demographic factors, and parental atopy. From 2001 to 2005, 1264 mother–infant pairs were recruited to participate in a birth cohort study. Prenatal questionnaire was used to collect family history, maternal gestational conditions and mentality, and environmental exposures. Cord blood was collected and assayed for genotypes and IgE levels. Phone interviews at 6 months and 2 yrs of age were conducted to inquire children’s health status, including AD occurrence. In addition to the known risk factors such as gender, maternal education, and parental atopy, biomarkers and maternal mentality during pregnancy were screened by logistic regression as candidate predictors of AD. Area‐under‐curve (AUC) statistic from receiver‐operating characteristic (ROC) curve analysis was used to compare two predicting models with and without biomarkers and maternal mentality. A total of 730 pairs completed the prenatal questionnaire and phone interview and were included in final analysis. The prevalence of ever having physician‐diagnosed AD by 2‐yr‐olds was 5.9%. Elevated cbIgE levels (≥0.5 kU/l), LT‐αNcoI alleles, FcεRI‐β E237G genotype, and maternal psychologic stress during pregnancy were significantly associated with AD. Comparison with AUCs of the classic model (including gender, maternal education, and parental atopy), the model adding cbIgE levels, genotypes in cytokine genes, and maternal stress (model 2) showed higher ability to discriminate between children with and without AD (AUC statistics: 0.63 [95% CI = 0.60–0.67] vs. 0.73 [95% CI = 0.70–0.76], respectively; model comparison, p = 0.027). We conclude that elevated cbIgE, LT‐α and FcεRI‐β genotypes, and maternal stress during pregnancy were associated with ever having physician‐diagnosed AD in 2‐yr‐old children and increased the predictive ability for AD after taking into account gender, maternal education, and parental atopic history.

This investigation provides a technique for predicting the risk of infantile AD based on hereditary and environmental factors, which could be used for developing a preventive strategy against AD, especially among those children with a family history of atopy.