Expression of mouse telomerase catalytic subunit in embryos and adult tissues

Telomerase is a ribonucleoprotein complex that elongates telomeres, allowing the stable maintenance of chromosomes during multiple cell divisions. Here, we describe the isolation and characterization of the catalytic subunit of mouse telomerase, mTERT (mouse telomerase reverse transcriptase), an essential protein component of the telomerase complex. During embryonic development, mTERT mRNA is abundantly expressed in the whole embryo, especially in regions of intense proliferation. We found that the mTERT mRNA expression in both embryonic and adult tissues is independent of the essential RNA component of telomerase, mTR, and therefore, of the formation of active telomerase complexes. mTERT protein is present exclusively in tissues with telomerase activity, such as testis, spleen, and thymus. mTERT protein is barely detectable in the thymus of mTR−/− mice, suggesting that mTERT protein stability in this tissue may depend on the actual assembly of active telomerase complexes. Finally, we found that mouse and human telomerase catalytic subunit is located in the cell nucleus, and its localization is not regulated during cell cycle progression.

Spatial memory is related to hippocampal subcellular concentrations of calcium-dependent protein kinase C isoforms in young and aged rats

Relationships were examined between spatial learning and hippocampal concentrations of the α, β2, and γ isoforms of protein kinase C (PKC), an enzyme implicated in neuronal plasticity and memory formation. Concentrations of PKC were determined for individual 6-month-old (n = 13) and 24-month-old (n = 27) male Long–Evans rats trained in the water maze on a standard place-learning task and a transfer task designed for rapid acquisition. The results showed significant relationships between spatial learning and the amount of PKC among individual subjects, and those relationships differed according to age, isoform, and subcellular fraction. Among 6-month-old rats, those with the best spatial memory were those with the highest concentrations of PKCγ in the particulate fraction and of PKCβ2 in the soluble fraction. Aged rats had increased hippocampal PKCγ concentrations in both subcellular fractions in comparison with young rats, and memory impairment was correlated with higher PKCγ concentrations in the soluble fraction. No age difference or correlations with behavior were found for concentrations of PKCγ in a comparison structure, the neostriatum, or for PKCα in the hippocampus. Relationships between spatial learning and hippocampal concentrations of calcium-dependent PKC are isoform-specific. Moreover, age-related spatial memory impairment is associated with altered subcellular concentrations of PKCγ and may be indicative of deficient signal transduction and neuronal plasticity in the hippocampal formation.

Contribution of parental blood pressures to association between low birth weight and adult high blood pressure: cross sectional study

Objective: To examine the possibility that low birth weight is a feature of the inherited predisposition to high blood pressure.

Identification of two novel transmembrane γ-carboxyglutamic acid proteins expressed broadly in fetal and adult tissues

The proline-rich γ-carboxyglutamic acid (Gla) proteins (PRGPs) 1 and 2 are the founding members of a family of vitamin K-dependent single-pass integral membrane proteins characterized by an extracellular amino terminal domain of approximately 45 amino acids that is rich in Gla. The intracellular carboxyl terminal region of these two proteins contains one or two copies of the sequence PPXY, a motif present in a variety of proteins involved in such diverse cellular functions as signal transduction, cell cycle progression, and protein turnover. In this report, we describe the cloning of the cDNAs for two additional human transmembrane Gla proteins (TMG) of 20–24 kDa named TMG3 and TMG4. These two proteins possess extracellular Gla domains with 13 or 9 potential Gla residues, respectively, followed by membrane-spanning hydrophobic regions and cytoplasmic carboxyl terminal regions that contain PPXY motifs. This emerging family of integral membrane Gla proteins includes proline-rich Gla protein (PRGP) 1, PRGP2, TMG3, and TMG4, all of which are characterized by broad and variable distribution in both fetal and adult tissues. Members of this family can be grouped into two subclasses on the basis of their gene organization and amino acid sequence. These observations suggest novel physiological functions for vitamin K beyond its known role in the biosynthesis of proteins involved in blood coagulation and bone development. The identification and characterization of these proteins may allow a more complete understanding of the teratogenic consequences of exposure in utero to vitamin K antagonists, such as warfarin-based anticoagulants.

Different modes of hippocampal plasticity in response to estrogen in young and aged female rats

Estrogen regulates hippocampal dendritic spine density and synapse number in an N-methyl-d-aspartate (NMDA) receptor-dependent manner, and these effects may be of particular importance in the context of age-related changes in endocrine status. We investigated estrogen's effects on axospinous synapse density and the synaptic distribution of the NMDA receptor subunit, NR1, within the context of aging. Although estrogen induced an increase in axospinous synapse density in young animals, it did not alter the synaptic representation of NR1, in that the amount of NR1 per synapse was equivalent across groups. Estrogen replacement in aged female rats failed to increase axospinous synapse density; however, estrogen up-regulated synaptic NR1 compared with aged animals with no estrogen. Therefore, the young and aged hippocampi react differently to estrogen replacement, with the aged animals unable to mount a plasticity response generating additional synapses, yet responsive to estrogen with respect to additional NMDA receptor content per synapse. These findings have important implications for estrogen replacement therapy in the context of aging.

Evaluation of hybrid and distance education learning environments in Spain

This article describes the adaptation and validation of the Distance Education Learning Environments Survey (DELES) for use in investigating the qualities found in distance and hybrid education psycho-social learning environments in Spain. As Europe moves toward post-secondary student mobility, equanimity in access to higher education, and more standardised degree programs across the European Higher Education Area (EHEA) the need for a high quality method for continually assessing the excellence of distance and hybrid learning environments has arisen. This study outlines how the English language DELES was adapted into the new Spanish-Distance Education Learning Environments Survey (S-DELES) for use with a Bachelor of Psychology and Criminology degree program offering both distance and hybrid education classes. We present the relationships between psycho-social learning environment perceptions and those of student affect. We also present the asynchronous aspects of the environment, scale means, and a comparison between the perceptions of distance education students and their hybrid education counterparts that inform the university about the baseline health of the information and communication technologies (ICT) environment within which the study was conducted.

Implementing the Physical Literacy Component of the 2015 Ontario Health and Physical Education Curriculum: Is the Stage Set?

Introduction: Current physical activity levels among children and youth are alarmingly low; a mere 7% of children and youth are meeting the Canadian Physical Activity Guidelines (Colley et al., 2011), which means that the vast majority of this population is at risk of developing major health problems in adulthood (Janssen & Leblanc, 2010). These high inactivity rates may be related to suboptimal experiences in sport and physical activity stemming from a lack of competence and confidence (Lubans, Morgan, Cliff, Barnett, & Okely, 2010). Developing a foundation of physical literacy can encourage and maintain lifelong physical activity, yet this does not always occur naturally as a part of human growth (Hardman, 2011). An ideal setting to foster the growth and development of physical literacy is physical education class. Physical education class can offer all children and youth an equal opportunity to learn and practice the skills needed to be active for life (Hardman, 2011). Elementary school teachers are responsible for delivering the physical education curriculum, and it is important to understand their will and capacity as the implementing agents of physical literacy development curriculum (McLaughlin, 1987). Purpose: The purpose of this study was to explore the physical literacy component of the 2015 Ontario Health and Physical Education curriculum policy through the eyes of key informants, and to explore the resources available for the implementation of this new policy. Methods: Qualitative interviews were conducted with seven key informants of the curriculum policy development, including two teachers. In tandem with the interviews, a resource inventory and curriculum review were conducted to assess the content and availability of physical literacy resources. All data were analyzed through the lens of Hogwood and Gunn’s (1984) 10 preconditions for policy implementation. Results: Participants discussed how implementation is affected by: accountability, external capacity, internal capacity, awareness and understanding of physical literacy, implementation expertise, and policy climate. Discussion: Participants voiced similar opinions on most issues, and the overall lack of attention given to physical education programs in schools will continue to be a major dilemma when trying to combat such high physical inactivity levels.

Comparative regional perspectives: the Bologna process and higher education attainment. Jean Monnet/Robert Schumann Paper Series Vol 13 No. 11, August 2013

Since 1999, countries have voluntarily chosen to reform their higher education systems to join the European Higher Education Area. This paper compares Bologna Process implementation across four regions within the European Union. While there are 47 countries participating in the Bologna Process, this paper uses statistical analysis to consider 25 of the 28 EU Member States. The time period of analysis is 2000-2011, prior to Croatia’s accession to the EU on 1 July 2013. Across Europe there are inter-regional differences in how the Bologna Process has been implemented and in the political economy contexts that influence higher education reform for policy convergence. There are three explanatory variables in the political economy context: 1. competitive economic pressures and globalization 2. domestic politics at the national level 3. leadership from the supranational European Union that socially constructs regional norms Tertiary education attainment is the dependent variable of interest in this research. The objective of 40%, for 30-34 year olds, is Europe 2020 benchmark target. There are additional higher education reform criteria encompassed in the Bologna Process. These criteria concern Credit and Degree Structure, Quality Assurance, and Recognition of academic degrees among countries in the EHEA. This tertiary education attainment variable, which is of interest in this paper, does not capture the entire implementation process. Nevertheless, it is a measure of one important indicator of success in providing higher education access to populations within the context of democratic governance. This research finds that statistically GDP Per Capita is the most significant variable in relationship to tertiary education attainment across four regional areas in the European Union.