Using iWorx 214 System to Stimulate Innovative Learning in a Medical Science Laboratory

From traditional lecture and lab teaching to computerbasedactivities, technological advances have been applied tohealth care sciences education in an effort to enhance studentlearning. As educators, we facilitate the students’ journeytowards independent learning in accordance with currentstandards in science pedagogy, but must also help students learnhow to use technologies in order to seek, organize, analyze, andapply information appropriately. We implemented iWorx whichprovides computerized data recording and analysis using multipletransducers into the anatomy and physiology course to meet thepedagogical objective of providing students with active learningexercises that extend beyond topics covered in the lecture portionof the course, while circumventing problems encountered whencreating an introductory-level medical science lab. We found thatperforming simple activities such as ECG, EEG, EMG, andspirometry by using iWorx increases students’ comfort levels,knowledge and experience levels, and interest levels of laboratoryrelated skills. We observed these increases, which weredemonstrated in comparisons between scores in students’ labactivities, while using iWorx especially when students wereapplying the scientific method to physiological issues, usingcomputer-based laboratory equipment, and demonstratingknowledge of scientific methodologies. Designing hands-onlearning and new kinesthetic activities improves conceptuallearning in cardiovascular, neurological, muscular, andrespiratory physiology in the lectures. The student relative labpractical scores improved significantly. Pedagogical objectivescan be met in an overwhelmingly positive lab experience forstudents when health sciences faculty use computer-basedtechnologies

The relationships between depression and other outcomes of chronic illness caregiving

BACKGROUND: Many caregivers with chronically ill relatives suffer from depression. However, the relationship of depression to other outcomes of chronic caregiving remains unclear. This study tested a hypothesized model which proposed that hours of care, stressful life events, social support, age and gender would predict caregivers' outcomes through perceived caregiver stress. Depression was expected to mediate the relationship between perceived stress and outcomes of chronic caregiving (physical function, self-esteem, and marital satisfaction). METHODS: The sample for this secondary data analysis consisted of 236 and 271 subjects from the Americans' Changing Lives, Wave 1, 1986, and Wave 2, 1989, data sets. Measures were constructed from the original study. Structural equation modeling was used to test the hypothesized model, and an exploratory structural modeling method, specification search, was used to develop a data-derived model. Cross-validation was used to verify the paths among variables. RESULTS: Hours of care, age, and gender predicted caregivers' outcomes directly or through perceived caregiver stress (p < .01). Depression mediated the relationship between perceived stress and psychological outcomes and explained 40% and 11% of the variance in self-esteem and marital satisfaction, respectively. CONCLUSION: Depression predicted psychological outcomes. Whether depression predicts physical health outcomes needs to be further explored

Water-miscible organic cosolvents enhance phosphatidylinositol-specific phospholipase C phosphotransferase as well as phosphodiesterase activity

AbstractPhosphatidylinositol-specific phospholipase C (PI-PLC) from Bacillus thuringiensis catalyzes the hydrolysis of phosphatidylinositol (PI) in a Ca2+-independent two-step mechanism: (i) an intramolecular phosphotransferase reaction to form inositol 1,2-(cyclic)-phosphate (cIP), followed by (ii) a cyclic phosphodiesterase activity that converts cIP to inositol 1-phosphate (I-1-P). Moderate amounts of water-miscible organic solvents have previously been shown to dramatically enhance the cyclic phosphodiesterase activity, that is, hydrolysis of cIP. Cosolvents [isopropanol (iPrOH), dimethylsufoxide (DMSO), and dimethylformamide (DMF)] also enhance the phosphotransferase activity of PI-PLC toward PI initially presented in vesicles, monomers, or micelles. Although these water-miscible organic cosolvents caused large changes in PI particle size and distribution (monitored with pyrene-labeled PI fluorescence, 31P NMR spectroscopy, gel filtration, and electron microscopy) that differed with the activating solvent, the change in PI substrate structure in different cosolvents was not correlated with the enhanced catalytic efficiency of PI-PLC toward its substrates. PI-PLC stability was decreased in water/organic cosolvent mixtures (e.g., the Tm for PI-PLC thermal denaturation decreased linearly with added iPrOH). However, the addition of myo-inositol, a water-soluble inhibitor of PI-PLC, helped stabilize the protein. At 30% iPrOH and 4 °C (well below the Tm for PI-PLC in the presence of iPrOH), cosolvent-induced changes in protein secondary structure were minimal. iPrOH and diheptanoylphosphatidylcholine, each of which activates PI-PLC for cIP hydrolysis, exhibited a synergistic effect for cIP hydrolysis that was not observed with PI as substrate. This behavior is consistent with a mechanism for cosolvent activation that involves changes in active site polarity along with small conformational changes involving the barrel rim tryptophan side chains that have little effect on protein secondary structure

Fine-Scale Staging of T Cell Lineage Commitment in Adult Mouse Thymus

T cell development is marked by the loss of alternative lineage choices accompanying specification and commitment to the T cell lineage. Commitment occurs between the CD4 and CD8 double-negative (DN) 2 and DN3 stages in mouse early T cells. To determine the gene regulatory changes that accompany commitment, we sought to distinguish and characterize the earliest committed wild-type DN adult thymocytes. A transitional cell population, defined by the first downregulation of surface c-Kit expression, was found to have lost the ability to differentiate into dendritic cells and NK cells when cultured without Notch-Delta signals. In the presence of Notch signaling, this subset generates T lineage descendants in an ordered precursor–product relationship between DN2, with the highest levels of surface c-Kit, and c-Kit–low DN3 cells. These earliest committed cells show only a few differences in regulatory gene expression, compared with uncommitted DN2 cells. They have not yet established the full expression of Notch-related and T cell differentiation genes characteristic of DN3 cells before β selection. Instead, the downregulation of select stem cell and non-T lineage genes appears to be key to the extinction of alternative lineage choices

Lineage Divergence at the First TCR-Dependent Checkpoint: Preferential γδ and Impaired αβ T Cell Development in Nonobese Diabetic Mice

The first TCR-dependent checkpoint in the thymus determines αβ versus γδ T lineage fate and sets the stage for later T cell differentiation decisions. We had previously shown that early T cells in NOD mice that are unable to rearrange a TCR exhibit a defect in checkpoint enforcement at this stage. To determine if T cell progenitors from wild-type NOD mice also exhibit cellautonomous defects in development, we investigated their differentiation in the Notch-ligand–presenting OP9-DL1 coculture system, as well as by analysis of T cell development in vivo. Cultured CD4 and CD8 double-negative cells from NOD mice exhibited major defects in the generation of CD4 and CD8 double-positive αβ T cells, whereas γδ T cell development from bipotent precursors was enhanced. Limiting dilution and single-cell experiments show that the divergent effects on αβ and γδ T cell development did not spring from biased lineage choice but from increased proliferation of γδ T cells and impaired accumulation of αβ T lineage double-positive cells. In vivo, NOD early T cell subsets in the thymus also show characteristics indicative of defective β-selection, and peripheral αβ T cells are poorly established in mixed bone marrow chimeras, contrasting with strong γδ T as well as B cell repopulation. Thus, NOD T cell precursors reveal divergent, lineage-specific differentiation abnormalities in vitro and in vivo from the first TCR-dependent developmental choice point, which may have consequences for subsequent lineage decisions and effector functions

Temporary microglia-depletion after cosmic radiation modifies phagocytic activity and prevents cognitive deficits.

Microglia are the main immune component in the brain that can regulate neuronal health and synapse function. Exposure to cosmic radiation can cause long-term cognitive impairments in rodent models thereby presenting potential obstacles for astronauts engaged in deep space travel. The mechanism/s for how cosmic radiation induces cognitive deficits are currently unknown. We find that temporary microglia depletion, one week after cosmic radiation, prevents the development of long-term memory deficits. Gene array profiling reveals that acute microglia depletion alters the late neuroinflammatory response to cosmic radiation. The repopulated microglia present a modified functional phenotype with reduced expression of scavenger receptors, lysosome membrane protein and complement receptor, all shown to be involved in microglia-synapses interaction. The lower phagocytic activity observed in the repopulated microglia is paralleled by improved synaptic protein expression. Our data provide mechanistic evidence for the role of microglia in the development of cognitive deficits after cosmic radiation exposure

Neighbourhood ethnic mix and the formation of mixed-ethnic unions in Britain : a longitudinal analysis

This research is funded by the ESRC under the Understanding Population Trends and Processes (UPT AP) programme (Award Ref: RE S-163-25-0045).Although developed societies are becoming increasingly ethnically diverse, relatively little research has been conducted on geographies of mixed-ethnic unions (married or cohabiting). There is some recent evidence from the US that mixed-ethnic couples are more likely to be found in mixed-ethnic neighbourhoods, but this research is based on cross-sectional data. Therefore it is not possible to determine whether mixed-ethnic couples are more likely to form in mixed-ethnic neighbourhoods or whether they are more likely to move there. Our longitudinal analysis allows us to tease out the relative importance of these two processes, furthering our understanding of the formation of mixed-ethnic unions. Using data from the Office for National Statistics Longitudinal Study we examine neighbourhood effects on the formation of mixed-ethnic unions in England and Wales. We find that mixed-ethnic unions are more likely to form in neighbourhoods with low concentrations of co-ethnic population. The results from this study lend support to the contact theory that geographical proximity to other ethnic groups enhances mutual understanding between people from different ethnic groups and could lead to the development of intimate partnerships.PostprintPeer reviewe

Development of human single-chain antibodies against SARS-associated coronavirus.

The outbreak of severe acute respiratory syndrome (SARS), caused by a distinct coronavirus, in 2003 greatly threatened public health in China, Southeast Asia as well as North America. Over 1,000 patients died of the SARS virus, representing 10% of infected people. Like other coronaviruses, the SARS virus also utilizes a surface glycoprotein, namely the spike protein, to infect host cells. The spike protein of SARS virus consists of 1,255 amino acid residues and can be divided into two sub-domains, S1 and S2. The S1 domain mediates the binding of the virus to its receptor angiotensin-converting enzyme 2, which is abundantly distributed on the surface of human lung cells. The S2 domain mediates membrane fusion between the virus and the host cell. Hence two strategies can be used to block the infection of the SARS virus, either by interfering with the binding of the S1 domain to the receptor or by blocking the fusion of the virus with the cell membrane mediated by the S2 domain. Several antibodies against the S1 domain have been generated and all of them are able to neutralize the virus in vitro and in vivo using animal models. Unfortunately, point mutations have been identified in the S1 domain, so that the virus isolated in the future may not be recognized by these antibodies. As no mutation has been found in the S2 domain indicating that this region is more conserved than the S1 domain, it may be a better target for antibody binding. After predicting the immunogenicity of the epitopes of the S2 domain, we chemically synthesized two peptides and also expressed one of them using a recombinant DNA method. We screened a phage displaying library of human single-chain antibodies (ScFv) against the predicted epitopes and obtained a human ScFv which can recognize the SARS virus in vitro

Induction of Gynogenesis in Muskellunge With Irradiated Sperm of Yellow Perch Proves Diploid Muskellunge Male Homogamety

Diploid gynogenesis was induced in muskellunge Esox masquinongy using UV-irradiated muskellunge sperm as the first step in producing monosex females. In this approach, we have to rely on negative controls as an indirect reference for sperm genetic material destruction. In the first experiment, equal proportions of gynogenetic females and males were produced. Negative controls, UV-irradiated sperm without heat shock, yielded some normal hatching larvae, described as spontaneous diploids. In the second experiment, muskellunge eggs were activated using sperm from yellow perch. Because hybrids between these species are not viable, we produced unambiguous gynogens. When UV-irradiated yellow perch sperm was used to inseminate muskellunge eggs, haploids resulted (22.5% ± 2.8% survival to the eyed stage). To produce diploid gynogens, a heat shock of 31°C was applied to inseminated eggs 20 min after activation for a duration of 6 min. This process yielded several hundreds of gynogens for rearing. Several treatments of masculinizing hormone, 17 α-methyltestosterone (MT), were carried out. Fish were dissected and gonads examined histologically for sex determination. Gynogens produced using yellow-perch sperm confirmed the presence of males in the control group, whereas the MT bath treatment (400 μg/liter) resulted in the production of fish with ovotestis. These results provide evidence for male homogamety in muskellunge and imply that a change of strategy is needed to produce monosex populations.Funding for this project was provided by the Federal Aid in Sport Fish Restoration Program (F-69-P, Fish Management in Ohio), administered jointly by the U.S. Fish and Wildlife Service and the Ohio Division of Wildlife