Learner concerns and teaching strategies for video-conferencing

BACKGROUND: The purpose of this study was to understand the influences of interactive video-conferencing technology on learning experiences of RN students studying for baccalaureate degrees via interactive distance education. METHOD: Data collection in this phenomenological study used open-ended questionnaires, interviews, and focus groups. Preliminary thematic analysis of questionnaires shaped open-ended questions for interviews and focus groups with learners confirmed findings. RESULTS: Students identified themes of connecting with others, organization, negative influences, and personal factors as influential to their learning. They also identified useful teaching strategies to facilitate learning within this distance nursing education environment. CONCLUSION: University nursing programs using video-conferencing for distance education can foster learning by using teaching strategies that fit the technology, increase student interaction, and engage the students.     

Guar gum reduces postprandial hypotension in older people

OBJECTIVE: To determine whether slowing of gastric emptying and glucose absorption with guar gum would reduce the fall in blood pressure after an oral glucose load in older subjects. DESIGN: A randomized, experimental, cross-over study. SETTING: Department of Nuclear Medicine, Royal Adelaide Hospital, Adelaide, SA, Australia. PARTICIPANTS: Ten healthy subjects, age 67 to 78. MEASUREMENTS: Simultaneous measurements of gastric emptying, blood pressure, blood glucose, serum insulin, and oral glucose absorption (3-O-methyl-D-glucose [3-OMG]) on two occasions after ingestion of 300 mL water containing 50 g glucose and 30 mL lemon juice, 3 g 3-OMG labeled with 99mTc-sulphur colloid; with or without 9 g guar gum. Blood pressure and gastric emptying were monitored for 180 minutes. RESULTS: The magnitude of the falls in systolic (P = .02), diastolic (P < .05), and mean arterial (P = .05) blood pressure were less, and gastric emptying slower (P < .05), after guar. Blood glucose, insulin, and 3-OMG concentrations were reduced (P < .001 for all) by guar. 3-OMG concentrations were inversely related to the intragastric retention of glucose (r = -0.72, P = .02) and blood pressure was inversely related to 3-OMG (r = -0.64, P < .05) after the drink without guar. The blood glucose concentration was related to 3-OMG (r > 0.64, P < .05). CONCLUSION: Guar gum reduces the magnitude of the fall in blood pressure after oral glucose. Slowing of gastric emptying and glucose absorption may represent a novel approach to the treatment of postprandial hypotension.     

The degree of fat saturation does not alter glycemic,insulinemic or satiety responses to a starchy staple in healthy men

Inclusion of fat reduces the glycemic response to a carbohydate meal, although the effect of different types of fat on glycemic, insulinemic and satiety responses is unclear. Ten healthy men received 50-g carbohydrate portions of mashed potato with isoenergetic amounts of butter (saturated fatty acid), Sunola oil (monounsaturated fatty acid) or sunflower oil (PUFA) and two 50-g glucose loads on separate days. Capillary blood was collected at regular intervals for 2 h. Satiety ratings were assessed by use of a rating scale. The glycemic index (GI), insulin index (II) and satiety index (SI) scores were calculated. Energy intakes from a meal consumed ad libitum at 2 h and for the remainder of the day were quantified. The GI values ranged from 68 +/- 8 to 74 +/- 10 and the II values ranged from 113 +/- 10 to 122 +/- 17, but there was no effect of fat type. SI scores and subsequent energy intake did not differ among the test meals. Substitution of unsaturated fats for saturated fatty acids had no acute benefits on postprandial glycemia, insulin demand or short-term satiety in young men.     

Characterization of Rny1, the Saccharomyces cerevisiae member of the T2 RNase family of RNases: unexpected functions for ancient enzymes?

The T(2) family of nonspecific endoribonucleases (EC ) is a widespread family of RNases found in every organism examined thus far. Most T(2) enzymes are secretory RNases and therefore are found extracellularly or in compartments of the endomembrane system that would minimize their contact with cellular RNA. Although the biological functions of various T(2) RNases have been postulated on the basis of enzyme location or gene expression patterns, the cellular roles of these enzymes are generally unknown. In the present work, we characterized Rny1, the only T(2) RNase in Saccharomyces cerevisiae. Rny1 was found to be an active, secreted RNase whose gene expression is controlled by heat shock and osmotic stress. Inactivation of RNY1 leads to unusually large cells that are temperature-sensitive for growth. These phenotypes can be complemented not only by RNY1 but also by both structurally related and unrelated secretory RNases. Additionally, the complementation depends on RNase activity. When coupled with a recent report on the effect of specific RNAs on membrane permeability [Khvorova, A., Kwak, Y-G., Tamkun, M., Majerfeld, I. & Yarus, M. (1999) Proc. Natl. Acad. Sci. USA 96, 10649-10654], our work suggests an unexpected role for Rny1 and possibly other secretory RNases. These enzymes may regulate membrane permeability or stability, a hypothesis that could present an alternative perspective for understanding their functions.     

STUDIES ON THE SPASMOLYTIC AND UTERINE RELAXANT ACTIONS OF N -ETHYL AND N -BENZYL-1,2-DIPHENYL ETHANOLAMINES: ELUCIDATION OF THE MECHANISMS OF ACTION

The influence of N -ethyl- and N -benzyl-1,2-diphenyl ethanolamines (compounds E and B, respectively) was examined on the spontaneously contracting rabbit jejunum and the rat uterus together with their influence on the contractions induced by some spasmogens in the guinea-pig ileum and oxytocics and CaCl₂in the pregnant rat uterus. Both E and B inhibited the spontaneous contractions of the rabbit jejunum with ID₅₀values of 0.13 and 0.03 μmol ml⁻¹. Their inhibitory activities were not antagonized by α- or β-adrenoceptor blockers but significantly reversed by CaCl₂(0.015 μmol ml⁻¹). The compounds also antagonized nicotine, ACh-, histamine-, 5-HT- and CaCl₂-induced contractions by 44–100%. Compound E seemed to be several times more potent than B in inhibiting the spontaneous uterine contractions with an ID₅₀of (7 nmol ml⁻¹). Their inhibitory effects were not antagonized by β₂-adrenoceptor or H₂-receptor blocking drugs. Both compounds (40 nmol ml⁻¹) antagonized in a competitive manner CaCl₂-induced contractions in the K⁺-depolarised uterus and PGE₂and oxytocin-induced uterine contractions. The ID₅₀values were in the range of 1.6–10.7 nmol ml⁻¹. The results suggest that E and B compounds may be considered as putative L-Ca²⁺channel blockers with certain selectivities. The E compound seemed to be more selective against uterine L-Ca²⁺channels and the B compound against intestinal smooth muscles. Thus, the compounds may be of potential value in treatment of some colics, the irritant bowel syndrome, dysmenorrhoea and premature deliveries. 1999 Academic Press@p$hr     

The use of DNA markers for carrier detection and prenatal diagnosis of haemophilia A in Egyptian families

Summary. Haemophilia A is the most common inherited X‐linked recessive bleeding disorder. The aim was to investigate the usefulness of two DNA markers in linkage analysis, one intragenic BCL1 affecting restriction site in intron 18, and is detected as restriction fragment length polymorphism (RFLP), and one extragenic variable number of tandem repeat (VNTR) locus DXS52 (St14) to formulate an informative and accurate carrier detection and prenatal diagnosis. The study included 46 families with at least one child affected with haemophilia A, and 30 unrelated normal females as control group. Polymerase chain reaction (PCR) and restriction enzyme analysis were used to study the polymorphism in BCL1, and long‐distance PCR for detection of VNTR (ST14) alleles. The incidence of BCL1 (+) allele was 74%, 72% and 60% in patients, mothers and control group, respectively. Expected heterozygosity for BCL1 was 40% in mothers of affected cases compared with 48% in the female control group. However, observed heterozygosity was found to be 48% in the mothers of affected cases, compared with 60% in the control group. Thus, 48% of the studied families are informative for this marker alone. Nine different alleles of VNTR (St14) were observed in mothers and six alleles in affected cases and six in the control group. The most prevalent alleles were 1300 bp (45.5% and 34%) and 700 bp (13.6% and 20%) in patients and their mothers, respectively. Observed heterozygosity in mothers was 41% compared with 43.3% in controls. The combined use of both BCL1 and St14 markers raised the informative rate to 63.6%. Carrier detection and prenatal diagnosis is possible in haemophilia A families using both DNA markers. We suggest screening haemophilic families first for BCL1 polymorphism followed by analysis of St14 locus.     

Correlation of changes between 2-year disease-free survival and 5-year overall survival in adjuvant breast cancer trials from 1966 to 2006.

BACKGROUND: Although disease-free survival (DFS) is accepted as a valid end point in adjuvant breast cancer trials, improvement in 2-year DFS has never been formally established as an adequate correlate for 5-year overall survival (OS). We set out to ascertain if changes in 2-year DFS can be used to accurately predict 5-year OS changes. DESIGN: We conducted a systematic Medline search (1966-2006) for randomized adjuvant breast cancer trials of >100 patients per arm with 2-year DFS and 5-year OS data. A univariate regression model weighted by trial sample size was constructed to determine whether 2-year DFS differences between treatment arms within trials were predictive of 5-year OS differences. RESULTS: A total of 126 studies containing 149 treatment comparisons met the inclusion criteria. Difference in 2-year DFS was a significant predictor of difference in 5-year OS. For every 1% increase in 2-year DFS difference, the 5-year OS difference increased by 0.5%-0.55%. The proportion of variation explained ranged from 0.38 to 0.42, with a wide prediction interval. CONCLUSION: There is a statistically significant correlation, of moderate strength, between difference in 2-year DFS between treatment comparisons and difference in 5-year OS but the correlation is not strong enough to be used as a predictor.     

Compartment syndrome after surgery in the lithotomy position

Compartment syndrome developed in five patients after prolonged surgery in the lithotomy position. Four different surgeons performed the operations. Serious morbidity resulted from the syndrome and could have been prevented by consideration of the factors that predispose to its development: tight bindings; direct pressure on the calves; and prolonged time in the lithotomy position. The pathogenesis of compartment syndrome in this group of patients is discussed.     

Temporal variability of microenvironmental time budgets in Maryland.

Information on human time-activity patterns is often required to interpret environmental exposure data fully and to implement exposure assessment models. Data on short-term time-activity patterns for individuals, such as 1-day measurements, are relatively abundant. The reliability of such data for use in chronic exposure (e.g., 1 or more years) assessments performed for evaluation of health risks is not well understood. As part of the NHEXAS-Maryland investigation, daily time budget data for seven microenvironments were collected from 80 people during as many as six 1-week Cycles over a 12-month period. The data were summarized and analyzed statistically by sampling Cycle, day of week, and individual to characterize long-term average microenvironmental time budgets and to identify their determinants. Median times spent in transit, indoors at home, outside at home, indoors at work or school, outdoors at work or school, indoors at other locations, and outdoors at other locations were found to vary significantly, although not substantively in many cases, by time of year (i.e., Cycle), by day of week, and by individuals. Time budgets for most of the microenvironments also exhibited significant variability by gender, age group, education level, annual household income, and work status. The results indicate that short-term (e.g., 1-day) measures of microenvironmental time budgets for individuals are unlikely to be representative of their long-term patterns. Thus, health risk or epidemiological assessments performed for a population mean or specific quantile may be relatively insensitive to when time budget data were collected. However, the accuracy of such assessments performed for individuals is likely to be greatly improved by collection of time budget data from numerous points in time.