Rheological characterisation of dextran-concanavalin A mixtures as a basis for a self-regulated drug delivery device.

The rheological characterisation of glucose sensitive mixtures containing dextran and concanavalin A (con A) with and without glucose, was undertaken using oscillatory rheometry at 20 and 37 degrees C so that comparative data could be gathered in the linear viscoelastic (LVE) range. Measurements for a series of mixtures showed that complex viscosity is a function not only of the con A concentration but of the content and molecular weight of the dextran used. The extent of liquefaction on addition of glucose also depended on these factors. The tan delta profiles confirmed the change from semi-solid towards fluid behaviour. This occurs when glucose effects dismantling of the three-dimensional structure of the dextran-con A system by competitive binding to the glucose receptors in the protein. For the mixtures studied, the changes occurred between contents of 0 and 1% (w/w) glucose at 20 and 37 degrees C and form a useful basis for the formulation of a self-regulating delivery device for the control of hyper-and hypoglycaemia in diabetes.     

Powerlessness Regarding Health-Service Barriers: Construction of an Instrument

PURPOSE. The purpose of the study was to develop a scale to calculate college students' powerlessness regarding health service barriers (PHSB). METHODS. Scale items were generated to represent two domains of interest: powerlessness and college students' powerlessness regarding health service barriers. The final 20-item instrument was subjected to multiple measures of validity with college students and panels of nurse experts in the area of nursing diagnosis. Reliability was assessed by two samples (n = 92 and n = 33) of college-age students. A final administration was conducted with 197 college students. FINDINGS. The PHSB scale was determined to be an accurate and consistent measure. CONCLUSIONS. This instrument will provide a reliable and valid measure to conduct research.     

Genotyping of Chlamydia trachomatis in Urine Specimens Will Facilitate Large Epidemiological Studies

The serovars of Chlamydia trachomatis-positive urine specimens (n = 81; as detected by PCR and ligase chain reaction) were successfully analyzed in 94% of cases by omp1 PCR-based RFLP analysis. The use of urine specimens and this simple and sensitive typing method will greatly facilitate epidemiological studies of C. trachomatis serovar distribution in asymptomatic C. trachomatis infections in both females and males.     

Lymphoblastoid α-Interferon for Chronic Hepatitis C: A Randomized Controlled Study

Forty patients with chronic hepatitis C (CHC) were included in an open randomized controlled trial of lymphoblastoid α-interferon (L-IFN) versus no treatment. Twenty patients entered each group, and features of therapy and control cases were similar. L-IFN was given in low doses (1.5-4.5 megaunits) for 1 yr. In 16 of 20 patients treated with L-IFN (80%), but in only one of 20 nontreated cases (0.5%; p < 0.001), aminotransferase activities became normal. In four patients there was a reactivation of the disease during treatment after 4, 5, 6, and 8 months with normal aminotransferase levels. A posttherapy reactivation of hepatitis was observed in four additional cases after 1, 1, 1, and 3 months of follow-up. The other eight patients (40%) continued with normal aminotransferase levels for 1.52 ± 0.74 (range, 1-2.1) yr after IFN doses were discontinued. In all treated patients except two nonresponders, but in only one of 20 nontreated cases ( p < 0.001), Knodell's histological activity index decreased. Procollagen type III aminoterminal peptide levels did not change significantly in nontreated and nonresponder patients, diminished slightly in patients with a transient response, and normalized in cases with a long-standing response, suggesting that this serum test may be a reliable marker for monitoring response to IFIN therapy in patients with CHC. Finally, L-IFN treatment induced significant increments in CD4/CD8 index, phytohemagglutinin-induced blastogenesis, and natural killer activity. This study shows that L-IFN diminish inflammatory and fibrogenic activity in most patients with CHC. In 40% of patients treated in this trial, a long-standing remission of the disease was observed.     

School-Based Cardiovascular Health Promotion: The Child and Adolescent Trial for Cardiovascular Health (CATCH)

The Child and Adolescent Trial for Cardiovascular Health (CATCH) is a multisite intervention research study that builds on significant progress made in school health education research in the 1980s. The study has three phases: Phase I deals with study design, intervention, and measurement development, Phase II involves the main trial in 96 schools in four states, and Phase III focuses on analysis. The intervention program targets third-fifth grade students and focuses on multiple cardiovascular health behaviors, including eating habits, physical activity, and cigarette smoking. Classroom curricula, school environmental change, and family involvement programs are developed for each grade level and behavioral focus. This paper describes Phase II of CATCH with a rationale for cardiovascular health promotion with youth. The process of change that appears to be necessary for school-based health promotion and that will be tested in CATCH are presented as a framework to guide these efforts.     

Ketoconazole Impairs Early Pregnancy and the Decidual Cell Response via Alterations in Ovarian Function

Ketoconazole (KCZ) is an imidazole antifungal agent that alsoaffects P450 enzymes of the mammalian steroidogenic system.Several steps in the ovarian steroidogenesis pathway are knownto be inhibited by KCZ, but previous work has failed to addressthe ramifications of such inhibition with respect to early pregnancy.In initial studies, Holtzman rats (8–10/group) were administered10–100 mg/kg KCZ during days 1–8 of pregnancy. Onday 9, evaluations revealed a reduction at both 75 and 100 mgKCZ/kg in the number of implantation sites and serum progesteronelevels as well as an increase in ovarian weight The decidualcell response (DCR) was blocked by KCZ in parallel with decreasedserum progesterone and increased ovarian weight, indicatingdirect interference with uterine function. KCZ had no effectwhen given to long-term-ovariectomized rats that were hormonesupplemented to permit the DCR, indicating that the ovary wasat least one site of KCZ action on early pregnancy. Measurementof ovarian progesterone production in vitro from ovaries removedfrom rats treated in vivo with KCZ indicated a decline in progesteroneproduction, suggesting a direct effect of KCZ on ovarian steroidogenesis.These data demonstrate that KCZ can compromise early pregnancyand appears to do so by inhibiting progesterone synthesis inthe ovary.     

BUILDING COMMUNITY: Developing Skills for Interprofessional Health Professions Education and Relationship-Centered Care

In 1995, the National League for Nursing commissioned a Panel on Interdisciplinary/Transdisciplinary Education. The focus of the Panel's work was to examine educational issues that transcend the health professions and to make recommendations for future implementation of an interdisciplinary approach to addressing them. This article is being simultaneously published by several professional journals. The goal is to seek as much feedback as possible.     

Beta carotene uptake into atherosclerotic plaque: Enhanced staining and preferential ablation with the pulsed dye laser

The yellow color of atherosclerotic plaque is due to the presence of carotenoids, which absorb light between 430–530 nm and account for the preferential ablation of plaque by the pulsed dye laser operating at 480 nm. This study was designed to examine tissue uptake of β-carotene and the effect of uptake on arterial plaque ablation. Forty-two atherosclerotic NZW rabbits were given intravenous β-carotene at a dose of 40 mg/kg, twice weekly and killed between 1 hour and 28 days after the initial injection. β-carotene was not detected in control specimens but was significantly greater in plaque than in normal wall at all time points following β-carotene injection (P < 0.04 Mann Whitney U test). The ablation threshold was significantly lower in β-carotene treated plaque than in untreated plaque or normal arterial wall (P < 0.01, Fisher's exact test). In this model β-carotene is preferentially taken up into arterial plaque, resulting in increased absorption of laser radiation at 480 nm and enhanced tissue ablation. © 1993 Wiley-Liss, Inc.